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Penn Large Water Tunnel | Open Energy Information
Open Energy Info (EERE)
Penn Large Water Tunnel Penn Large Water Tunnel Jump to: navigation, search Basic Specifications Facility Name Penn Large Water Tunnel Overseeing Organization Pennsylvania State University Hydrodynamics Hydrodynamic Testing Facility Type Tunnel Length(m) 4.3 Beam(m) 1.2 Depth(m) 1.2 Water Type Freshwater Cost(per day) Contact POC Special Physical Features Closed loop; Turbulence level = 0.1%; Pressure range = 3-60psi; Controlled cavitation = # >0.1; Control Air content = >1ppm per mole Towing Capabilities Towing Capabilities None Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Velocity(m/s) 16.8 Recirculating Yes Pressure Range(Psi) 3 - 60 Wind Capabilities Wind Capabilities None Control and Data Acquisition Description National Instruments steady 24 bit
Wind Tunnel Measurements of the Response of Hot-Wire Liquid Water Content Instruments to Large Droplets
Science Conference Proceedings (OSTI)
Wet wind tunnel tests were performed on more than 23 cloud liquid water content (LWC) probes and drop spectrometers at the NASA Icing Research Tunnel, with a main objective to characterize their response to large-droplet conditions. As a part of ...
J. W. Strapp; J. Oldenburg; R. Ide; L. Lilie; S. Bacic; Z. Vukovic; M. Oleskiw; D. Miller; E. Emery; G. Leone
E-Print Network (OSTI)
Yellowfin tuna (Thunnus albacares) swimming kinematics was studied in a large water tunnel at controlled swimming velocities (U). Quantified kinematic variables included the tail-beat frequency, stride length (l), caudal amplitude, yaw, the propulsive wavelength, the speed of the propulsive wave (C) and the sweepback angle of the pectoral fins. In general, all variables, except the propulsive wavelength and consequently C, are comparable to values determined for other teleosts. The propulsive wavelength for the tunas (1.23–1.29L, where L is fork length) is 30–60 % longer than in other cruise-adapted teleosts such as salmonids. The resulting thunniform swimming mode and the morphological and anatomical adaptations associated with the long propulsive wavelength (e.g. fusiform body shape, rigid vertebral column) act to minimize anterior resistance and maximize caudal thrust. The long propulsive wavelength also increases the maximum l which, in concert with the elevated muscle temperatures of tunas, increases their maximum swimming velocity.
Iii Kinematics; Heidi Dewar; Jeffrey; B. Graham
Studies of tropical tuna swimming performance in a large water tunnel
The body temperatures (Tb) of nine yellowfin tuna (Thunnus albacares) were monitored while fish swam in a large water tunnel at controlled velocities (U) and ambient temperatures (Ta). Monitoring Tb during step changes in Ta at constant U permitted estimation of the thermal rate coefficient (k), an index of heat transfer. In the yellowfin, k is dependent on both Ta and the direction of the thermal gradient (i.e. whether Ta is greater or less than Tb). Modulation of k in response to Ta was further demonstrated during tests in which U was varied; the elevation of Tb in response to equal increases in U was 3–4 times less at 30 ?C than at 25 and 20 ?C. These experiments demonstrate that the yellowfin tuna can modulate heat transfer. This ability could prevent overheating during intense activity, retard heat loss during a descent into cool water and permit increased heat gain upon returning to warm surface waters (i.e. when Tb Heidi Dewar; Jeffrey B. Graham; Richard; W. Brill 1994-01-01T23:59:59.000Z
Heidi Dewar; Jeffrey B. Graham; Richard; W. Brill
The metabolic rates (V ? O?) of three tropical tunas [yellowfin tuna (Thunnus albacares), kawakawa (Euthynnus affinis) and skipjack (Katsuwonus pelamis)] were estimated using a large water-tunnel respirometer. Experiments lasting up to 31 h were used to determine the effects of velocity (U) on tuna V ? O ? over a range of U (17?150 cm s ?1) and temperatures (18–30 ?C). Replicate tests were carried out on several fish. The swimming V ? O ? of yellowfin is temperature-dependent (Q10=1.67, determined over intervals of 3–5 ?C). For yellowfin and skipjack, it was also possible to partition metabolic costs between maintenance and locomotion. The standard metabolic rate (SV ? O?) was estimated by extrapolation of the U/V ? O ? function to U=0. Comparisons of SV ? O ? for different size groups of yellowfin show that the mass-specific scaling exponent for V ? O ? is ?0.40. The SV ? O ? of tuna is comparable to values determined previously by stasis respirometry and is approximately three times higher than that of salmonids. Further comparisons with salmonids show that the slope of the U/V ? O ? function is less for tunas, which demonstrate a greater swimming efficiency.
I. Energetics; Heidi Dewar; Jeffrey; B. Graham
Carderock Large Cavitation Tunnel | Open Energy Information
Large Cavitation Tunnel Large Cavitation Tunnel Jump to: navigation, search Basic Specifications Facility Name Carderock Large Cavitation Tunnel Overseeing Organization United States Naval Surface Warfare Center Hydrodynamic Testing Facility Type Tunnel Length(m) 13.1 Beam(m) 3.0 Depth(m) 3.0 Water Type Freshwater Cost(per day) Contact POC Special Physical Features The Large Cavitation Channel was designed as a variable pressure, recirculating, cavitation tunnel with a very low acoustic background level; test section pressure: 3.5-414 kPa (0.03 to 4 atmospheres, 0.5 to 60 psia); air content: 10% to 100% saturation Towing Capabilities Towing Capabilities None Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Velocity(m/s) 18 Recirculating Yes Wind Capabilities
Penn Small Water Tunnel | Open Energy Information
Water Tunnel Water Tunnel Jump to: navigation, search Basic Specifications Facility Name Penn Small Water Tunnel Overseeing Organization Pennsylvania State University Hydrodynamics Hydrodynamic Testing Facility Type Tunnel Length(m) 0.8 Beam(m) 0.3 Depth(m) 0.3 Water Type Freshwater Cost(per day) Contact POC Special Physical Features Closed loop; Turbulence level = 0.1%; Pressure range = 3-60psi; Controlled cavitation = # >0.1; Control Air content = >1ppm per mole Towing Capabilities Towing Capabilities None Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Velocity(m/s) 21 Recirculating Yes Pressure Range(Psi) 3 - 60 Wind Capabilities Wind Capabilities None Control and Data Acquisition Description National Instruments dynamic analyzer, 24-bit
Carderock 2-ft Variable Pressure Cavitation Water Tunnel | Open Energy
2-ft Variable Pressure Cavitation Water Tunnel 2-ft Variable Pressure Cavitation Water Tunnel Jump to: navigation, search Basic Specifications Facility Name Carderock 2-ft Variable Pressure Cavitation Water Tunnel Overseeing Organization United States Naval Surface Warfare Center Hydrodynamic Testing Facility Type Tunnel Beam(m) 0.6 Depth(m) 0.6 Water Type Freshwater Cost(per day) Contact POC Special Physical Features The 2-Foot Variable Pressure Cavitation Water Tunnel is a vertical plane, closed recirculating, variable-speed, variable-pressure, open jet test section, closed jet test section, and semi-rectangular test section. Towing Capabilities Towing Capabilities None Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Velocity(m/s) 17 Recirculating Yes
Carderock 3-ft Variable Pressure Cavitation Water Tunnel | Open Energy
Variable Pressure Cavitation Water Tunnel Variable Pressure Cavitation Water Tunnel Jump to: navigation, search Basic Specifications Facility Name Carderock 3-ft Variable Pressure Cavitation Water Tunnel Overseeing Organization United States Naval Surface Warfare Center Hydrodynamic Testing Facility Type Tunnel Beam(m) 0.7 Depth(m) 0.7 Water Type Freshwater Cost(per day) Contact POC Special Physical Features The 3-ft Variable Pressure Cavitation Water Tunnel is a vertical plane, closed recirculating with resorber, variable-speed, variable-pressure, two interchangeable circular test sections. Towing Capabilities Towing Capabilities None Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Velocity(m/s) 25.8 Recirculating Yes Wind Capabilities Wind Capabilities None
Icing Wind Tunnel Tests on the CSIRO Liquid Water Probe
Wet wind tunnel tests have been Performed on several versions of the CSIRO probe designed for the airborne measurement of liquid water content. Four different controller units and 17 different Probe sensors (including half-size and shielded ...
W. D. King; J. E. Dye; D. Baumgardner; J. W. Strapp; D. Huffman
Probing water structures in nanopores using tunneling currents
We study the effect of volumetric constraints on the structure and electronic transport properties of distilled water in a nanopore with embedded electrodes. Combining classical molecular dynamics simulations with quantum scattering theory, we show that the structural motifs water assumes inside the pore can be probed directly by tunneling. In particular, we show that the current does not follow a simple exponential curve at a critical pore diameter of about 8 {\\AA}, rather it is larger than the one expected from simple tunneling through a barrier. This is due to a structural transition from bulk-like to "nanodroplet" water domains. Our results can be tested with present experimental capabilities to develop our understanding of water as a complex medium at nanometer length scales.
P. Boynton; M. Di Ventra
Vacuum gaps with small tunnel currents at large electric field...
NLE Websites -- All DOE Office Websites (Extended Search)
gap can help to reduce tunnel currents. We discuss applications of this technology for energy storage, charge storage, and power supplies. Speaker Bio: Professor Alfred Hubler...
Calibrations of Johnson-Williams Liquid Water Content Meters in a High-Speed Icing Tunnel
Wind tunnel tests have provided calibrations and intercomparisons of 14 Johnson-Williams (J–W) cloud liquid water content (LWC) measuring devices with 23 sensor heads from 10 research organizations. The absolute tunnel LWC was deduced using a ...
J. Walter Strapp; Robert S. Schemenauer
Vacuum gaps with small tunnel currents at large electric field and its
Vacuum gaps with small tunnel currents at large electric field and its Vacuum gaps with small tunnel currents at large electric field and its potential applications for energy storage, charge storage and power supplies. Friday, May 27, 2011 - 4:00pm SSRL Conference Room 137-226 Alfred Hubler, Department of Physics, University of Illinois, Urbana-Champaign We study tunnel currents and electric break down in vacuum gaps experimentally and theoretically. We find that electric field at break down in nano vacuum gaps is 3 order of magnitude larger than in macroscopic capacitors. Pointed electrodes increase the limiting field even further. Eigen states in the gap can help to reduce tunnel currents. We discuss applications of this technology for energy storage, charge storage, and power supplies. Speaker Bio: Professor Alfred Hubler is the director of the Center for
Table 8: Water Consumption Information for Large Hospitals
U.S. Energy Information Administration (EIA)
Water Consumption Information for Large Hospitals, 2007 Table H8. RSEs for Water Consumption Information for Large Hospitals, 2007 Number of Large Hospital Buildings
Variational transition state theory calculations of tunneling effects on concerted hydrogen motion in water clusters and formaldehyde/water clusters
SciTech Connect
The direct participation of water molecules in aqueous phase reaction processes has been postulated to occur via both single-step mechanisms as well as concerted hydrogen atom or proton shifts. In the present work, simple prototypes of concerted hydrogen atom transfer processes are examined for small hydrogen-bonded water clusters -- cyclic trimers and tetramers -- and hydrogen-bonded clusters of formaldehyde with one and two water molecules. Rate constants for the rearrangement processes are computed using variational transition state theory, accounting for quantum mechanical tunneling effects by semiclassical ground-state adiabatic transmission coefficients. The variational transition state theory calculations directly utilize selected information about the potential energy surface along the minimum energy path as parameters of the reaction path Hamiltonian. The potential energy information is obtained from ab ignite electronic structure calculations with an empirical bond additivity correction (the BAC-MP4 method). Tunneling is found to be very important for these concerted rearrangement processes -- the semiclassical ground-state adiabatic transmission coefficients are estimated to be as high as four order of magnitude at room temperature. Effects of the size of the cluster (number of water molecules in the cyclic complex) are also dramatic -- addition of a water molecule is seen to change the calculated rates by orders of magnitude. 36 refs., 10 figs.
Garrett, B.C. (Pacific Northwest Lab., Richland, WA (USA)); Melius, C.F. (Sandia National Labs., Livermore, CA (USA))
Performance Comparison of Large Diameter Residential Drinking Water Wells.
??Published scientific work indicates that residential large diameter drinking water wells are at a higher risk of contamination from surface water impacts than drilled wells.… (more)
Javor, Paul
A Wind Tunnel Investigation on the Riming of Snowflakes. Part I: Porous Disks and Large Stellars
The effects of porosity on the accretional growth characteristics of ice crystal aggregates (snowflakes) are investigated by riming circular disks of ice in a cloud tunnel. Twelve disk models were used, sized 5 to 6 mm and 10 to 11 mm in diameter,...
Jeffrey K. Lew; Derek C. Montague; Hans R. Pruppacher; Roy M. Rasmussen
Actinide Sorption in Rainier Mesa Tunnel Waters from the Nevada Test Site
The sorption behavior of americium (Am), plutonium (Pu), neptunium (Np), and uranium (U) in perched Rainier Mesa tunnel water was investigated. Both volcanic zeolitized tuff samples and groundwater samples were collected from Rainier Mesa, Nevada Test Site, NV for a series of batch sorption experiments. Sorption in groundwater with and without the presence of dissolved organic matter (DOM) was investigated. Am(III) and Pu(IV) are more soluble in groundwater that has high concentrations of DOM. The sorption K{sub d} for Am(III) and Pu(IV) on volcanic zeolitized tuff was up to two orders of magnitude lower in samples with high DOM (15 to 19 mg C/L) compared to samples with DOM removed (Rainier Mesa, the low actinide Kd values measured in groundwater with high DOM concentrations must be incorporated in predictive transport models.
Zhao, P; Zavarin, M; Leif, R; Powell, B; Singleton, M; Lindvall, R; Kersting, A
Large energy gaps in CaC{sub 6} from tunneling spectroscopy : possible evidence of strong-coupling superconductivity.
Tunneling in CaC{sub 6} crystals reproducibly reveals superconducting gaps {Delta} of 2.3 {+-} 0.2 meV that are {approx}40% larger than reported earlier. In an isotropic s-wave scenario, that puts CaC{sub 6} into the class of very strongly coupled superconductors, since 2{Delta}/kT{sub c}-4.6, implying that soft Ca phonons are primarily involved in the superconductivity. This conclusion explains the relatively large Ca isotope effect found recently for CaC{sub 6}, but it could also signal a strong anisotropy in the electron-phonon interaction.
Kurter, C.; Ozyuzer, L.; Mazur, D.; Zasadzinski, J. F.; Rosenmann, D.; Claus, H.; Hinks, D. G.; Gray, K. E.; Materials Science Division; Illinois Inst. of Tech.; Izmir Inst. of Tech.
Student Pages: RFP-Large-Scale Diversion of Water
Supplying Our Water Needs H2O Request For Proposal Large Scale Diversion of Water U.S. Army Corp of Engineers-Chicago District online Be sure to submit the online sign-off each...
Property:Channel/Tunnel/Flume | Open Energy Information
Channel/Tunnel/Flume Channel/Tunnel/Flume Jump to: navigation, search Property Name Channel/Tunnel/Flume Property Type String Pages using the property "Channel/Tunnel/Flume" Showing 25 pages using this property. (previous 25) (next 25) 1 1.5-ft Wave Flume Facility + Yes + 10-ft Wave Flume Facility + Yes + 11-ft Wave Flume Facility + None + 2 2-ft Flume Facility + Yes + 3 3-ft Wave Flume Facility + None + 5 5-ft Wave Flume Facility + Yes + 6 6-ft Wave Flume Facility + Yes + A Alden Large Flume + Yes + Alden Small Flume + Yes + Alden Tow Tank + None + Alden Wave Basin + None + B Breakwater Research Facility + None + Bucknell Hydraulic Flume + Yes + C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + Yes + Carderock 3-ft Variable Pressure Cavitation Water Tunnel + Yes +
Wind Tunnel Tests of the Airborne PVM-100A Response to Large Droplets
The Gerber Scientific, Inc. Particle Volume Monitor (PVM) is widely used to measure the liquid water content (LWC) and droplet effective radius (reff) of water clouds. The LWC response of the airborne version of this instrument, the PVM-100A, was ...
M. Wendisch; T. J. Garrett; J. W. Strapp
Large Lenses of Highly Saline Mediterranean Water
Isolated compact anticyclonic eddies or salt lenses were found in the Canary Basin. Hydrographic surveys of three such lenses show large anomalies of salinity and temperature (0.8, 2.5°C). They are centered at 1100 m, have a vertical extent of ...
Laurence Armi; Walter Zenk
ARM - PI Product - Large Scale Ice Water Path and 3-D Ice Water Content
ProductsLarge Scale Ice Water Path and 3-D Ice Water ProductsLarge Scale Ice Water Path and 3-D Ice Water Content Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Large Scale Ice Water Path and 3-D Ice Water Content Site(s) SGP TWP General Description Cloud ice water concentration is one of the most important, yet poorly observed, cloud properties. Developing physical parameterizations used in general circulation models through single-column modeling is one of the key foci of the ARM program. In addition to the vertical profiles of temperature, water vapor and condensed water at the model grids, large-scale horizontal advective tendencies of these variables are also required as forcing terms in the single-column models. Observed horizontal advection of condensed water has not been available because the
The sorption behavior of americium (Am), plutonium (Pu), neptunium (Np), and uranium (U) in perched Rainier Mesa tunnel water was investigated. Both volcanic zeolitized tuff samples and groundwater samples were collected from Rainier Mesa, Nevada Test Site, NV for a series of batch sorption experiments. Sorption in groundwater with and without the presence of dissolved organic matter (DOM) was investigated. Am(III) and Pu(IV) are more soluble in groundwater that has high concentrations of DOM. The sorption K{sub d} for Am(III) and Pu(IV) on volcanic zeolitized tuff was up to two orders of magnitude lower in samples with high DOM (15 to 19 mg C/L) compared to samples with DOM removed (< 0.4 mg C/L) or samples with naturally low DOM (0.2 mg C/L). In contrast, Np(V) and U(VI) sorption to zeolitized tuff was much less affected by the presence of DOM. The Np(V) and U(VI) sorption Kds were low under all conditions. Importantly, the DOM was not found to significantly sorb to the zeolitized tuff during these experiment. The concentration of DOM in groundwater affects the transport behavior of actinides in the subsurface. The mobility of Am(III) and Pu(IV) is significantly higher in groundwater with elevated levels of DOM resulting in potentially enhanced transport. To accurately model the transport behavior of actinides in groundwater at Rainier Mesa, the low actinide Kd values measured in groundwater with high DOM concentrations must be incorporated in predictive transport models.
Optimal Operation of Large Agricultural Watersheds with Water Quality Restraints
Improved technology is needed for use in properly managing large agricultural watersheds. Proper watershed management means selecting land uses that are appropriate for each subarea, using erosion control measures where necessary, and applying fertilizers at rates that maximize agricultural production without polluting the environment. Watershed runoff and industrial and municipal effluents pollute streams and reservoirs. Point source pollution (industries and municipalities) can be monitored. Nonpoint-source pollution (watersheds) is widely dispersed and not easily measured. Mathematical models are needed to predict nonpoint-source pollution as affected by watershed characteristics, land use, conservation practices, chemical fertilizers, and climatic variables. Routing models are needed to determine the quality of water as it flows from nonpoint sources through streams and valleys to rivers and large reservoirs. Models are also needed to determine optimal strategies for planning land use, conservation practices, and fertilizer application to maximize agricultural production subject to water quality constraints. Three of the most important agricultural pollutants are suspended sediment, phosphorus, and nitrogen. Robinson [1971] pointed out that sediment is the greatest pollutant of water in terms of volume. Sediment also transports other pollutants, like phosphorus and nitrogen. These two elements are principally involved in lake eutrophication. Frequently algae blooms develop in nutrient-laden water and cause it to have an off-taste and an unpleasant odor. The odor of decaying plants becomes offensive; fish are killed because of reduced dissolved oxygen in the water, and recreation is deterred. The objective of this research was to develop models for use in managing large agricultural watersheds to obtain maximum agricultural production and to maintain water quality standards. The models were designed to: 1. Simulate daily runoff, and sediment, phosphorus, and nitrogen yields from small watersheds (areas land owners and operators) for planning land use, fertilizer application, and conservation practices on subwatersheds. 4. Determine the optimal strategy for each subwatershed to maximize agricultural production for the entire watershed subject to water quality constraints. Generally, water-quality models are developed by adding chemical modeling components to existing runoff and sediment models because runoff and sediment provide transportation for chemicals. Several conceptual models for predicting chemical yields from small watersheds have been presented [Crawford and Donigian, 1973; Donigian and Crawford, 1976; Frere, et al., 1975; Hagin and Amberger, 1974; Kling, 1974; Johnson and Straub, 1971]. However, these models are not applicable to large watersheds because they have no routing mechanism. For this reason, runoff, sediment, and nutrient models were refined and developed here for application to large watersheds. Probably, the most widely used and accepted model for predicting runoff volume is the Soil Conservation Service (SCS) curve number system [U.S. Soil Conservation Service, 1972]. The SCS model was modified by adding a soil-moisture-index accounting procedure [Williams and Laseur, 1976]. The modified water yield model is considerably more accurate than the original SCS model. On a watershed near Riesel, Texas, the modified model explained 95% of the variation in monthly runoff as compared with 65% for the original model. The water-yield model was refined here by replacing the climatic index (lake evaporation) with daily consumptive water use for individual crops.
Williams, J. R.; Hann, R. W.
GADZOOKS! Antineutrino Spectroscopy with Large Water Cerenkov Detectors
We propose modifying large water \\v{C}erenkov detectors by the addition of 0.2% gadolinium trichloride, which is highly soluble, newly inexpensive, and transparent in solution. Since Gd has an enormous cross section for radiative neutron capture, with $\\sum E_\\gamma = 8$ MeV, this would make neutrons visible for the first time in such detectors, allowing antineutrino tagging by the coincidence detection reaction $\\bar{\
John F. Beacom; Mark R. Vagins
An automatic water management system for large-scale rice paddy fields
An automatic water management system for large-scale paddy fields has been developed. The purposes of that are to supply the paddy fields with water or drain water from that automatically, to decrease water consumption, and to have a good harvest. To ... Keywords: estimating mean water level, optimal water allocation, paddy field, predict field consumption, prediction of growth stages, water level control
Teruji Sekozawa
A Wind Tunnel Study of Turbulence Effects on the Scavenging of Aerosol Particles by Water Drops
Laboratory experiments are described where the effects of turbulence on the impaction scavenging of aerosol particles by water drops were investigated. During the experiments the drops were freely suspended at their terminal velocities in the ...
O. Vohl; S. K. Mitra; K. Diehl; G. Huber; S. C. Wurzler; K-L. Kratz; H. R. Pruppacher
Safety implications of a large LNG tanker spill over water.
The increasing demand for natural gas in the United States could significantly increase the number and frequency of marine LNG (liquefied natural gas) imports. Although many studies have been conducted to assess the consequences and risks of potential LNG spills, the increasing importance of LNG imports suggests that consistent methods and approaches be identified and implemented to help ensure protection of public safety and property from a potential LNG spill. For that reason the U.S. Department of Energy (DOE), Office of Fossil Energy, requested that Sandia National Laboratories (Sandia) develop guidance on a risk-based analysis approach to assess and quantify potential threats to an LNG ship, the potential hazards and consequences of a large spill from an LNG ship, and review prevention and mitigation strategies that could be implemented to reduce both the potential and the risks of an LNG spill over water. Specifically, DOE requested: (1) An in-depth literature search of the experimental and technical studies associated with evaluating the safety and hazards of an LNG spill from an LNG ship; (2) A detailed review of four recent spill modeling studies related to the safety implications of a large-scale LNG spill over water; (3) Evaluation of the potential for breaching an LNG ship cargo tank, both accidentally and intentionally, identification of the potential for such breaches and the potential size of an LNG spill for each breach scenario, and an assessment of the potential range of hazards involved in an LNG spill; (4) Development of guidance on the use of modern, performance-based, risk management approaches to analyze and manage the threats, hazards, and consequences of an LNG spill over water to reduce the overall risks of an LNG spill to levels that are protective of public safety and property.
Hightower, Marion Michael; Gritzo, Louis Alan; Luketa-Hanlin, Anay Josephine
SNM Detection with a Large Water Cerenkov Detector
Special Nuclear Material (SNM) can either spontaneously fission, or be induced to do so. Either case results in neutron emission. Since neutrons are highly penetrating and difficult to shield, they could, potentially, be detected escaping even a well shielded cargo container. Obviously, if the shielding is sophisticated, detecting it would require a highly efficient detector with close to 4{pi} solid angle coverage. Water Cerenkov detectors may be a cost effective way to achieve that goal if it can be shown that the neutron capture signature is large enough and if sufficient background rejection can be employed as detectors get larger. In 2008 the LLNL Advanced Detector Group reported the successful detection of neutrons with a 1/4 ton gadolinium doped water Cerenkov prototype. We have now built a 4 ton version. This detector is not only bigger, it was designed with photon detection efficiency in mind from the beginning. We are employing increased photocathode coverage and more reflective walls, coated with PTFE. The increased efficiency should allow better energy resolution. We expect that the better diffusive wall reflectivity will reduce the overall dependence of the detector response on particle direction, again producing a more consistent response. We also believe that as detectors get larger, both uncorrelated and correlated backgrounds due to gamma-rays and cosmic ray interactions near the detector will increase. To prove the effectiveness of the technology we must develop new ways to reject these backgrounds while maintaining our sensitivity to SNM neutrons. Better energy resolution will enable us to reject more of the low energy gamma-ray backgrounds on this basis. Overcoming cosmic ray induced neutrons is perhaps an even larger concern as detectors get larger. Our detector is designed so that we can test various segmentation schemes - effectively dividing the detector up into smaller ones. In this presentation, we will describe our detector in detail.
Dazeley, S; Bernstein, A; Bowden, N; Ouedraogo, S; Svoboda, R; Sweeny, M
Plan for support of large-plant (post-CRBR) needs in large-leak sodium-water reaction area
Work in the large leak test and analysis area of steam generator development has been carried out at GE-ARSD under 189a SG037 since 1973. The currently planned master schedule for the SG037 program is shown. Principal activities are the large leak testing program being carried out at the Large Leak Test Rig and the analysis methods development. The plan for supporting the large plant (post-CRBR) needs in the large leak sodium-water reaction area is outlined. Most of the needs will be answered in the current SG037 large leak program. (DLC)
Whipple, J.C.
An Evaluation Of Large Diameter Steel Water Pipelines.
??Najafi, Mohammad Steel water pipelines, as a part of America's underground infrastructure, play a key role in maintaining the quality of life and well-being of… (more)
Joshi, Tushar
Glendale Water and Power - Large Business Energy Efficiency Program...
Energy.gov (U.S. Department of Energy (DOE)) Indexed Site
its medium and large business customers with electric bills of more than 3000 per month (electric usage of 250,000 kWh annually 36,000 per year) to encourage energy efficiency...
Large scale Li17Pb83/water interaction studies
One current concept in fusion blanket design is to utilize water as the coolant and liquid lithium-lead as the breeding/neutron-multiplier material. Considering the possibility of certain off-normal events it is conceivable that water leakage into the liquid metal may occur due to a tube rupture. The BLAnket Safety Test facility (BLAST) simulates this transient event by injecting sub-cooled water, under high pressure, into a stagnant loop of liquid lithium-lead (Li17Pb83). In this paper the BLAST facility will be described, such as the various mechanical components and the measurement devices. The current results of the data analyses from the first three experiments are also presented.
Kranert, O.; Kottowski, H.M.; Savatteri, C.
Large scale solar hot water heating systems for green hospital
Concerns over the impact of the environment on the massive usage of fossil fuels, combined with soaring energy prices, triggered increased interest in the use of solar energy. Solar energy is abundant, provides an important saving to the consumer, and ... Keywords: energy savings, evacuated tubes, greenhouse gas reduction, solar assisted hot water heaters
Poorya Ooshaksaraei; Baharudin Ali; Sohif Mat; M. Yahya; Kamaruzaman Ibrahim; Azami Zaharim; Kamaruzaman Sopian
MEMPHYS:A large scale water Cerenkov detector at Fréjus
A water \\v{C}erenkov detector project, of megaton scale, to be installed in the Fr\\'ejus underground site and dedicated to nucleon decay, neutrinos from supernovae, solar and atmospheric neutrinos, as well as neutrinos from a super-beam and/or a beta-beam coming from CERN, is presented and compared with competitor projects in Japan and in the USA. The performances of the European project are discussed, including the possibility to measure the mixing angle $\\theta_{13}$ and the CP-violating phase $\\delta$.
A. de Bellefon; J. Bouchez; J. Busto; J. -E. Campagne; C. Cavata; J. Dolbeau; J. Dumarchez; P. Gorodetzky; S. Katsanevas; M. Mezzetto; L. Mosca; T. Patzak; P. Salin; A. Tonazzo; C. Volpe
Conceptual Design of a Large, Passive Pressure-Tube Light Water Reactor
A design for a large, passive, light water reactor has been developed. The proposed concept is a pressure tube reactor of similar design to CANDU reactors, but differing in three key aspects. First, a solid SiC-coated ...
Hejzlar, P.
Predominantly Superconducting Origin of Large Energy Gaps in Underdoped Bi{sub 2} Sr{sub 2} CaCu{sub 2 }O{sub 8+ {delta}} from Tunneling Spectroscopy
New tunneling data are reported in Bi{sub 2}Sr {sub 2}CaCu{sub 2}O{sub 8+{delta}} which show quasiparticle excitation gaps, {Delta}, reaching values as high as 60thinspthinspmeV for underdoped crystals with T{sub c}=70 K . These energy gaps are nearly 3thinspthinsptimes larger than those of overdoped crystals with similar T{sub c} . Despite the large differences in gap magnitude, the tunneling spectra display qualitatively similar characteristics over the entire doping range. Detailed examination of the spectra, including the Josephson I{sub c}R{sub n} product measured in break junctions, indicates that these energy gaps are predominantly of superconducting origin. {copyright} {ital 1999} {ital The American Physical Society}
Miyakawa, N.; Zasadzinski, J.F.; Ozyuzer, L.; Guptasarma, P.; Hinks, D.G.; Gray, K.E. [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)] [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Miyakawa, N. [Department of Applied Physics, Science University of Tokyo, Kagurazaka 1-3, Shinjuku-ku, Tokyo 162-8601 (Japan)] [Department of Applied Physics, Science University of Tokyo, Kagurazaka 1-3, Shinjuku-ku, Tokyo 162-8601 (Japan); Zasadzinski, J.F. [Illinois Institute of Technology, Chicago, Illinois 60616 (United States)] [Illinois Institute of Technology, Chicago, Illinois 60616 (United States); Ozyuzer, L. [Department of Physics, Izmir Institute of Technology, TR-35230 Izmir (Turkey)] [Department of Physics, Izmir Institute of Technology, TR-35230 Izmir (Turkey); Kendziora, C. [Naval Research Laboratory, Washington, D.C. 20375 (United States)] [Naval Research Laboratory, Washington, D.C. 20375 (United States)
Effective fracture geometry obtained with large water sand ratio
Shale gas formation exhibits some unusual reservoir characteristics: nano-darcy matrix permeability, presence of natural fractures and gas storage on the matrix surface that makes it unique in many ways. It's difficult to design an optimum fracture treatment for such formation and even more difficult is to describe production behavior using a reservoir model. So far homogeneous, two wing fracture, and natural fracture models have been used for this purpose without much success. Micro seismic mapping technique is used to measure the fracture propagation in real time. This measurement in naturally fractured shale formation suggests a growth of fracture network instead of a traditional two wing fractures. There is an industry wise consensus that fracture network plays an important role in determining the well productivity of such formations. A well with high density of fracture networks supposed to have better productivity. Shale formations have also exhibited production pattern which is very different from conventional or tight gas reservoir. Initial flow period is marked by steep decline in production while the late time production exhibits a slow decline. One of the arguments put for this behavior is linear flow from a bi-wing fractured well at early time and contribution of adsorbed gas in production at late time. However, bi-wing fracture geometry is not supported by the micro-seismic observation. A realistic model should include both the fracture network and adsorbed gas property. In this research we have proposed a new Power Law Permability model to simulate fluid flow from hydraulically fractured Shale formation. This model was first described by Valko & Fnu (2002) and used for analyzing acid treatment jobs. The key idea of this model is to use a power law permeability function that varies with the radial distance from well bore. Scaling exponent of this power law function has been named power law index. The permeability function has also been termed as secondary permeability. This work introduces the method of Laplace solution to solve the problem of transient and pseudo steady-state flow in a fracture network. Development and validation of this method and its extension to predict the pressure (and production) behaviour of fracture network were made using a novel technic. Pressure solution was then combined with material balance through productivity index to make production forecast. Reservoir rock volume affected by the fracture stimulation treatment that contributes in the production is called effective stimulated volume. This represents the extent of fracture network in this case. Barnett shale formation is a naturally fractured shale reservoir in Fort Worth basin. Several production wells from this formation was analysed using Power Law Model and it was found that wells productivity are highly dependent on stimulated volume. Apparently the wells flow under pseudo steady state for most part of their producing life and the effect of boundary on production is evident in as soon as one months of production. Due to short period of transient flow production from Barnett formations is expected to be largely independent of the relative distribution of permeability and highly dependent on the stimulated area and induced secondary permeability. However, an indirect relationship between permeability distribution and production rate is observed. A well with low power law index shows a better (more even) secondary permeability distribution in spatial direction, larger stimulated volume and better production. A comparative analysis between the new model and traditional fracture model was made. It was found that both models can be used successfully for history matching and production forecasting from hydraulically fractured shale gas formation.
Kumar, Amrendra
Flooding Experiments with Steam and Water in a Large Diameter Vertical Tube
An experimental study on flooding with steam and water in a large diameter vertical tube was conducted. This research has been performed to provide a better prediction of flooding in a pressurized water reactor (PWR) pressurizer surge line to be used in reactor safety codes. Experiments were conducted using a 3-inch (76.2 mm) diameter tube 72 inches (1.83 m) long with subcooled water and super-heated steam at atmospheric pressure as the working fluids. Water flows down the inside walls of the tube as an annulus while the steam flows upward in the middle. The water flow rates ranged from 3.5 to 12 gallons per minute (GPM) (0.00022 to 0.00076 m^3/s) and the water inlet temperature was approximately 70 degrees C. The steam inlet temperature was approximately 110 degrees C. The size of the test section as well as the flow ranges of the working fluids was determined based on a scaling analysis of a PWR pressurizer surge line. Two distinct trends were observed in the data. It was found that for water flow rates below 6 GPM (0.00038 m3/s) the amount of steam required for flooding to occur decreases with an increasing water flow rate. For water flow rates above 6 GPM the amount of steam required for flooding to occur increases with an increasing water flow rate. In addition, axial water temperature data was collected. Axial water temperatures have not been recorded in previous flooding experiments with steam and water. A new correlation for predicting flooding with steam and water was proposed. This correlation was an improvement from previous correlations because it included the amount of steam condensation. Incorporation of steam-water mass exchange promotes a better prediction of behavior in reactor systems. This data for flooding with steam and water in a large diameter vertical tube can lead to a mechanistic model for flooding.
Williams, Susan Nicole
Flatback airfoil wind tunnel experiment.
DOE Green Energy (OSTI)
A computational fluid dynamics study of thick wind turbine section shapes in the test section of the UC Davis wind tunnel at a chord Reynolds number of one million is presented. The goals of this study are to validate standard wind tunnel wall corrections for high solid blockage conditions and to reaffirm the favorable effect of a blunt trailing edge or flatback on the performance characteristics of a representative thick airfoil shape prior to building the wind tunnel models and conducting the experiment. The numerical simulations prove the standard wind tunnel corrections to be largely valid for the proposed test of 40% maximum thickness to chord ratio airfoils at a solid blockage ratio of 10%. Comparison of the computed lift characteristics of a sharp trailing edge baseline airfoil and derived flatback airfoils reaffirms the earlier observed trend of reduced sensitivity to surface contamination with increasing trailing edge thickness.
Mayda, Edward A. (University of California, Davis, CA); van Dam, C.P. (University of California, Davis, CA); Chao, David D. (University of California, Davis, CA); Berg, Dale E.
Large-scale Gadolinium-doped Water Cerenkov Detector for Non-Proliferation
Fission events from Special Nuclear Material (SNM), such as highly enriched uranium or plutonium, can produce simultaneous emission of multiple neutrons and high energy gamma-rays. The observation of time correlations between any of these particles is a significant indicator of the presence of fissionable material. Cosmogenic processes can also mimic these types of correlated signals. However, if the background is sufficiently low and fully characterized, significant changes in the correlated event rate in the presence of a target of interest constitutes a robust signature of the presence of SNM. Since fission emissions are isotropic, adequate sensitivity to these multiplicities requires a high efficiency detector with a large solid angle with respect to the target. Water Cerenkov detectors are a cost-effective choice when large solid angle coverage is required. In order to characterize the neutron detection performance of large-scale water Cerenkov detectors, we have designed and built a 3.5 kL water Cerenko...
Sweany, M; Bowden, N S; Dazeley, S; Keefer, G; Svoboda, R; Tripathi, M
Subcooling Effects for Flooding Experiments with Steam and Water in a Large Diameter Vertical Tube
A counter current annular flow experiment was performed to determine flooding conditions for varying degrees of subcooling using steam and water. The findings can be used in reactor safety codes to provide an improved model of flooding during accident analysis. The test section is a stainless steel tube which is approximately a 5/16 scale version of a pressurized water reactor (PWR) surge line. The water flows in an annular film down the inside of the tube and steam flows upward through the annulus. Flooding is the point at which the water film reverses direction and begins to travel upward. Flooding tests were conducted at atmospheric pressure for water flow rates between 3.5 gallons per minute (GPM) and 11 GPM and water inlet temperatures between 35 degrees C and 97 degrees C. The data obtained at high water subcooling indicate a significant departure from accepted flooding correlations developed for air-water systems which is expected because vapor condensation alters the steam inlet flow rate needed to induce flooding. The data more closely follow air-water data at low subcooling. Such data has not been seen in the literature for steam-water flooding experiments in a large diameter vertical tube and will serve as an important benchmark.
Cullum, Wes
Carderock Subsonic Wind Tunnel | Open Energy Information
Subsonic Wind Tunnel Subsonic Wind Tunnel Jump to: navigation, search Basic Specifications Facility Name Carderock Subsonic Wind Tunnel Overseeing Organization United States Naval Surface Warfare Center Hydrodynamic Testing Facility Type Tunnel Length(m) 4.3 Beam(m) 3.0 Depth(m) 2.4 Water Type Freshwater Cost(per day) Contact POC Special Physical Features The Subsonic Wind Tunnel is a continuous flow, closed-circuit facility with a closed jet test section. Test models may be supported by strut mounts using the external balance or by sting mounts using any of a wide selection of internal strain gauge balances. Adjustable surface planes are available for simulation of ground or water surfaces. Full-width floor and ceiling turntables provide additional flexibility in model mounting and manipulation.
Calibration of Johnson–Williams and PMS ASSP Probes in a Wind Tunnel
Wet wind tunnel tests have provided calibrations and intercomparisons of the LAMP's cloud liquid water content probes (three Johnson–Williams sensor heads and one PMS ASSP). The tunnel liquid water content was deduced with a rotating cyclinder ...
J. F. Gayet
Tunnel magnetoresistance in epitaxially grown magnetic tunnel junctions using Heusler alloy electrode and MgO barrier
Epitaxially grown magnetic tunnel junctions (MTJs) with a stacking structure of Co{sub 2}MnSi/MgO/CoFe were fabricated. Their tunnel magnetoresistance (TMR) effects were investigated. The TMR ratio and tunnelling conductance characteristics of MTJs were considerably different between those with an MgO barrier prepared using sputtering (SP-MTJ) and those prepared using EB evaporation (EB-MTJ). The EB-MTJ exhibited a very large TMR ratio of 217% at room temperature and 753% at 2 K. The bias voltage dependence of the tunnelling conductance in the parallel magnetic configuration for the EB-MTJ suggests that the observed large TMR ratio at RT results from the coherent tunnelling process through the crystalline MgO barrier. The tunnelling conductance in the anti-parallel magnetic configuration suggests that the large temperature dependence of the TMR ratio results from the inelastic spin-flip tunnelling process.
Tsunegi, S.; Sakuraba, Y.; Oogane, M.; Telling, N. D.; Shelford, L. R.; Arenholz, E.; van der Laan, G.; Hicken, R. J.; Takanashi, K.; Ando, Y.
Breach and safety analysis of spills over water from large liquefied natural gas carriers.
In 2004, at the request of the Department of Energy, Sandia National Laboratories (Sandia) prepared a report, ''Guidance on the Risk and Safety Analysis of Large Liquefied Natural Gas (LNG) Spills Over Water''. That report provided framework for assessing hazards and identifying approaches to minimize the consequences to people and property from an LNG spill over water. The report also presented the general scale of possible hazards from a spill from 125,000 m3 o 150,000 m3 class LNG carriers, at the time the most common LNG carrier capacity.
Hightower, Marion Michael; Luketa-Hanlin, Anay Josephine; Attaway, Stephen W.
A GIS/Simulation Framework for Assessing Change in Water Yield over Large Spatial Scales
Recent legislation to,initiate vegetation management in the Central Sierra hydrologic region of California includes a focus on corresponding changes in water yield. This served as the impetus for developing a combined geographic information system (GIS) and simulation assessment framework. Using the existing vegetation density condition, together with proposed rules for thinning to reduce fire risk, a set of simulation model inputs were generated for examining the impact of the thinning scenario on water yield. The approach allows results to be expressed as the mean and standard deviation of change in water yield for each 1 km2 map cell that is treated. Values for groups of cells are aggregated for typical watershed units using area-weighted averaging. Wet, dry and average precipitation years were simulated over a large region. Where snow plays an important role in hydrologic processes, the simulated change in water yield was less than 0.5% of expected annual runoff for a typical water shed. Such small changes would be undetectable in the field using conventional stream flow analysis. These results suggest that use of water yield increases to help justify forest-thinning activities or offset their cost will be difficult.
Graham, R.; Hargrove, W.W.; Huff, D.D.; Nikolov, N.; Tharp, M.L.
Fission events from Special Nuclear Material (SNM), such as highly enriched uranium or plutonium, can produce simultaneous emission of multiple neutrons and high energy gamma-rays. The observation of time correlations between any of these particles is a significant indicator of the presence of fissionable material. Cosmogenic processes can also mimic these types of correlated signals. However, if the background is sufficiently low and fully characterized, significant changes in the correlated event rate in the presence of a target of interest constitutes a robust signature of the presence of SNM. Since fission emissions are isotropic, adequate sensitivity to these multiplicities requires a high efficiency detector with a large solid angle with respect to the target. Water Cerenkov detectors are a cost-effective choice when large solid angle coverage is required. In order to characterize the neutron detection performance of large-scale water Cerenkov detectors, we have designed and built a 3.5 kL water Cerenkov-based gamma-ray and neutron detector, and modeled the detector response in Geant4 [1]. We report the position-dependent neutron detection efficiency and energy response of the detector, as well as the basic characteristics of the simulation.
M. Sweany; A. Bernstein; N. S. Bowden; S. Dazeley; G. Keefer; R. Svoboda; M. Tripathi
Cost-efficient monitoring of water quality in district heating systems This article examines the monitoring strategy for water quality in a large Danish district
Cost-efficient monitoring of water quality in district heating systems This article examines the monitoring strategy for water quality in a large Danish district heating system  and makes a proposal for a technical and economic improvement. Monitoring of water quality in district heating systems is necessary
Effects of tunneling on groundwater flow and swelling of clay-sulfate rocks
[1] Swelling of clay-sulfate rocks is a major threat in tunneling. It is triggered by the transformation of the sulfate mineral anhydrite into gypsum as a result of water inflow in anhydrite-containing layers after tunnel ...
Butscher, Christoph
Tunnel closure calculations
When a deeply penetrating munition explodes above the roof of a tunnel, the amount of rubble that falls inside the tunnel is primarily a function of three parameters: first the cube-root scaled distance from the center of the explosive to the roof of the tunnel. Second the material properties of the rock around the tunnel, and in particular the shear strength of that rock, its RQD (Rock Quality Designator), and the extent and orientation of joints. And third the ratio of the tunnel diameter to the standoff distance (distance between the center of explosive and the tunnel roof). The authors have used CALE, a well-established 2-D hydrodynamic computer code, to calculate the amount of rubble that falls inside a tunnel as a function of standoff distance for two different tunnel diameters. In particular they calculated three of the tunnel collapse experiments conducted in an iron ore mine near Kirkeness, Norway in the summer of 1994. The failure model that they used in their calculations combines an equivalent plastic strain criterion with a maximum tensile strength criterion and can be calibrated for different rocks using cratering data as well as laboratory experiments. These calculations are intended to test and improve the understanding of both the Norway Experiments and the ACE (Array of conventional Explosive) phenomenology.
Moran, B.; Attia, A.
Regular Scanning Tunneling Microscope Tips can be Intrinsically Chiral
We report our discovery that regular scanning tunneling microscope tips can themselves be chiral. This chirality leads to differences in electron tunneling efficiencies through left- and right-handed molecules, and, when using the tip to electrically excite molecular rotation, large differences in rotation rate were observed which correlated with molecular chirality. As scanning tunneling microscopy is a widely used technique, this result may have unforeseen consequences for the measurement of asymmetric surface phenomena in a variety of important fields.
Tierney, Heather L.; Murphy, Colin J.; Sykes, E. Charles H. [Department of Chemistry, Tufts University, Medford, Massachusetts 02155-5813 (United States)
Operating Water Cherenkov Detectors in high altitude sites for the Large Aperture GRB Observatory
Water Cherenkov Detectors (WCD) are efficient detectors for detecting GRBs in the 10 GeV - 1 TeV energy range using the single particle technique, given their sensitivity to low energy secondary photons produced by high energy photons when cascading in the atmosphere. The Large Aperture GRB Observatory (LAGO) operates arrays of WCD in high altitude sites (above 4500 m a.s.l.) in Bolivia, Mexico and Venezuela, with planned extension to Peru. Details on the operation and stability of these WCD in remote sites with high background rates of particles will be detailed, and compared to simulations. Specific issues due to operation at high altitude, atmospheric effects and solar activity, as well as possible hardware enhancements will also be presented.
Allard, D; Asorey, H; Barros, H; Bertou, X; Castillo, M; Chirinos, J M; De Castro, A; Flores, S; González, J; Berisso, M Gomez; Grajales, J; Guada, C; Day, W R Guevara; Ishitsuka, J; López, J A; Martínez, O; Melfo, A; Meza, E; Loza, P Miranda; Barbosa, E Moreno; Murrugarra, C; Núńez, L A; Ormachea, L J Otiniano; Pérez, G; Perez, Y; Ponce, E; Quispe, J; Quintero, C; Rivera, H; Rosales, M; Rovero, A C; Saavedra, O; Salazar, H; Tello, J C; Peralda, R Ticona; Varela, E; Velarde, A; Villaseńor, L; Wahl, D; Zamalloa, M A
Superconductivity and electron tunneling
Experiments on the tunneling of electrons through a thin dielectric layer separating two superconducting metals are reported. Data are presented for the pairs AI-Pb, Sn-Pb, and In-Sn. Particular attention is paid to the form of the tunneling current ...
S. Shapiro; P. H. Smith; J. Nicol; J. L. Miles; P. F. Strong
A Vertical Wind Tunnel for Snow Process Studies
A vertical wind tunnel using an artificially generated supercooled cloud was constructed to study snowfall processes. It is 18 m high and operates to a temperature as low as ?25°C. Ultrasonic atomizers supply the supercooled water droplets, and ...
Tsuneya Takahashi; Chikara Inoue; Yoshinori Furukawa; Tatsuo Endoh; Renji Naruse
Numerical simulations of turbulent flow fields caused by spraying of water on large releases of hydrogen fluoride
The effectiveness of water sprays in absorbing HF releases was recently demonstrated in extended laboratory and field tests. In this paper, computer simulations are presented of the Hawk, Nevada Test Site, series of field tests. The model used, HFSPRAY, is a Eulerean/Lagrangian model which simulates the momentum, mass and energy interactions between a water spray and a turbulent plume of HF in air; the model can predict the flow velocities, temperature, water vapor, and HF concentration fields in two-dimensional large- geometries for spraying in any direction, (i.e., down-flow, inclined-down-flow, up-flow, and co-current horizontal flow). The model was validated against recent data on spraying of water on large releases of HF. 17 refs., 11 figs., 4 tabs.
Fthenakis, V.M. (Brookhaven National Lab., Upton, NY (United States)); Schatz, K.W. (Mobil Research and Development Corp., Princeton, NJ (United States))
On Factors Controlling AirWater Gas Exchange in a Large Tidal River
and Estuarine Research Federation 2011 Abstract AirÂwater gas exchange is an important process in aquatic Introduction In rivers and estuaries, knowledge of airÂwater gas exchange is important for evaluating how floating domes. The opportunistic gas method relies on gases in the water that either occurred naturally (e
Ho, David
The Design and Application of the Water Temperature Control System for Large Aquaculture Pond
Because the traditional cooling methods such as ice cooling and natural convection cooling can not meet the special requirements of ornamental fish breeding, the way based on mechanical refrigeration, heat exchange system, water supply system and automatic ... Keywords: aquaculture pond for ornamental fish, water temperature automatic control, mechanical refrigeration, plate exchanger, water supply system
Chen Shuai; Zhong Ke; Cai Yingling
MHK Technologies/Tunneled Wave Energy Converter TWEC | Open Energy
Tunneled Wave Energy Converter TWEC Tunneled Wave Energy Converter TWEC < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Tunneled Wave Energy Converter TWEC.jpg Technology Profile Primary Organization SeWave Ltd Project(s) where this technology is utilized *MHK Projects/TWEC Project Technology Resource Click here Wave Technology Type Click here Oscillating Water Column Technology Readiness Level Click here TRL 1-3: Discovery / Concept Definition / Early Stage Development & Design & Engineering Technology Description The Tunneled Wave Energy Converter TWEC utilizes the OWC principle through its use of a proposed bored out tunnel within a cliff side of the Faroe Islands Technology Dimensions Device Testing Date Submitted 10/8/2010 << Return to the MHK database homepage
A GIS-based tool for modelling large-scale crop-water relations
Recent research on crop-water relations has increasingly been directed towards the application of locally acquired knowledge to answering the questions raised on larger scales. However, the application of the local results to larger scales is often questionable. ... Keywords: Crop water productivity, EPIC, GEPIC, Maize, Rice, Wheat
Junguo Liu
Performance of Large Diameter Residential Drinking Water Wells - Biofilm Growth: Laboratory and Field Testing.
??In the first phase of this project three enhanced large diameter (> 60 cm) residential wells were constructed at a study site in Lindsay, Ontario.… (more)
Ruiz Salazar, Hector Fabio
Risk analysis for tunneling projects
Tunnel construction is increasing world wide. Although the majority of tunnel construction projects have been completed safely, there have been several incidents that have resulted in delays, cost overruns, and sometimes ...
Sousa. Rita L
Quantum tunneling time
A simple model of a quantum clock is applied to the old and controversial problem of how long a particle takes to tunnel through a quantum barrier. The model I employ has the advantage of yielding sensible results for energy eigenstates, and does not require the use of time-dependant wave packets. Although the treatment does not forbid superluminal tunneling velocities, there is no implication of faster-than-light signaling because only the transit duration is measurable, not the absolute time of transit. A comparison is given with the weak-measurement post-selection calculations of Steinberg.
P. C. W. Davies
Large Field Erected and Packaged High Temperature Water (HTW) Generators for Coal Firing
The purpose of the paper is to disseminate information on the energy savings possible with High Temperature Water (HTW) for heating and industrial process application and to provide information on coal fired HTW generator design and availability.
Boushell, C. C.
Giant tunneling magnetoresistance in Co{sub 2}MnSi/Al-O/Co{sub 2}MnSi magnetic tunnel junctions
Magnetic tunnel junctions (MTJs) with a stacking structure of Co{sub 2}MnSi/Al-O/Co{sub 2}MnSi were fabricated using magnetron sputtering system. Fabricated MTJ exhibited an extremely large tunneling magnetoresistance (TMR) ratio of 570% at low temperature, which is the highest TMR ratio reported to date for an amorphous Al-O tunneling barrier. The observed dependence of tunneling conductance on bias voltage clearly reveals the half-metallic energy gap of Co{sub 2}MnSi. The origins of large temperature dependence of TMR ratio were discussed on the basis of the present results.
Sakuraba, Y.; Hattori, M.; Oogane, M.; Ando, Y.; Kato, H.; Sakuma, A.; Miyazaki, T.; Kubota, H. [Department of Applied Physics, Graduate School of Engineering, Tohoku University, Aoba-yama 6-6-05, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Nanoelectronics Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba 305-8568 (Japan)
Commissioning the Domestic Hot Water System on a Large University Campus: A Case Study
The Texas A&M University (TAMU) main campus in College Station consists of 110 buildings with 12.5 million square feet of gross building space. Seventy-one of these buildings are connected to the main campus domestic hot water (DHW) distribution system. The DHW loop is more than 50 years old and has had continuing distribution problems. The main problems reported from several buildings were low hot water temperature and long delays in obtaining hot water at fixtures. The objective of this study was to investigate the causes of these problems and help determine how to best operate the system. It was found that reported problems of low flows, low temperatures and long hot water lag time resulted from reverse flows and no hot water circulation caused by: 1) Unadjusted return pumps with heads too high. 2) Pumps not installed or not running where needed. 3) Pumps with heads too low. 4) Check valves not installed where needed. 5) Insufficient piping capacity in two locations. This paper presents possible control strategies to alleviate these problems identified during the field investigation.
Chen, H.; Bensouda, N.; Claridge, D.; Bruner, H.
Alden Large Flume | Open Energy Information
Flume Flume Jump to: navigation, search Basic Specifications Facility Name Alden Large Flume Overseeing Organization Alden Research Laboratory, Inc Hydrodynamic Testing Facility Type Flume Length(m) 24.4 Beam(m) 6.1 Depth(m) 3.0 Water Type Freshwater Cost(per day) $5000/week Towing Capabilities Towing Capabilities Yes Maximum Velocity(m/s) 0.9 Maximum Velocity with Constriction(m/s) 3 Wavemaking Capabilities Wavemaking Capabilities Yes Maximum Wave Height(m) 0.0 Maximum Wave Height(m) at Wave Period(s) 0.0 Wave Period Range(s) 2.1 Current Velocity Range(m/s) 3.2 Programmable Wavemaking Yes Wavemaking Description Wave generators not yet designed Simulated Beach No Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Recirculating Yes Wind Capabilities Wind Capabilities Yes
PORTFOLIO RISK ASSESSMENT OF SA WATER'S LARGE DAMS by David S. Bowles1
dimensions [5] and high pressure and gravity die-casting [6,7]. Since the two-dimensional dam ridges. Water from the dam flows through the valley and into the sea under gravity. Immediately after-14 December 2001 Three-dimensional modelling of dam-break induced flows using Smoothed Particle Hydrodynamics
Bowles, David S.
A Wind Tunnel Investigation of the Effect of an External, Vertical Electric Field on the Shape of Electrically Uncharged Rain Drops
Results are presented of a recent wind tunnel experiment in which electrically unchanged water drops of 1000–3000 ?m equivalent radius were freely suspended in the vertical air stream of the UCLA Cloud Tunnel. During their suspension, the drops ...
R. Rasmussen; C. Walcek; H.R. Pruppacher; S.K. Mitra; J. Lew; V. Levizzani; P.K. Wang; U. Barth
Factors Influencing Water Heating Energy Use and Peak Demand in a Large Scale Residential Monitoring Study
A load research project by the Florida Power Corporation (FPC) is monitoring 200 residences in Central Florida, collecting detailed end-use load data. The monitoring is being performed to better estimate the impact of FPC's load control program, as well as obtain improved appliance energy consumption indexes and load profiles. A portion of the monitoring measures water heater energy use and demand in each home on a 15-minute basis.
Bouchelle, M. P.; Parker, D. S.; Anello, M. T.
Nonequilibrium transport in superconducting tunneling structures.
We derive the current-voltage (I-V) characteristics of far from equilibrium superconducting tunneling arrays and find that the energy relaxation ensuring the charge transfer occurs in two stages: (i) the energy exchange between charge carriers and the intermediate bosonic agent, environment, and (ii) relaxing the energy further to the (phonon) thermostat, the bath, provided the rate of the environmental modes-phonon interactions is slower than their energy exchange rate with the tunneling junction. For a single junction we find I {proportional_to} (V/R)ln({Lambda}/V), where R is the bare tunnel resistance of the junction and {Lambda} is the high energy cut-off of the electron-environment interaction. In large tunneling arrays comprised of macroscopic number of junctions, low-temperature transport is governed by the cotunneling processes losing energy to the electron-hole environment. Below some critical temperature, T*, the Coulomb interactions open a finite gap in the environment excitations spectrum blocking simultaneously Cooper pair and normal excitations currents through the array; this is the microscopic mechanism of the insulator-to-superinsulator transition.
Chtchelkatchev, N. M.; Vinokur, V. M.; Baturina, T. I. (Materials Science Division); (Moscow Inst. Physics and Technology); (Inst. Semiconductor Physics)
Antiparticle creation in tunneling
We study particle interaction with a Dirac step potential. In the standard Klein energy zone, the hypothesis of Klein pair production predicts the existence of free/oscillatory antiparticles. In this paper, we discuss the tunneling energy zone characterized by evanescent wave functions in the classically forbidden region. We ask the question of the nature, particle or antiparticle, of the densities within the classically forbidden region. The answer to this question is relevant to the correct form of the reflection coefficient.
Stefano De Leo; Pietro Rotelli
Computational design and analysis of flatback airfoil wind tunnel experiment.
Polarization Control of Electron Tunneling into Ferroelectric Surfaces
We demonstrate a highly reproducible control of local electron transport through a ferroelectric oxide via its spontaneous polarization. Electrons are injected from the tip of an atomic force microscope into a thin film of lead-zirconate titanate, Pb(Zr0.2Ti0.8)O3, in the regime of electron tunneling assisted by a high electric field (Fowler-Nordheim tunneling). The tunneling current exhibits a pronounced hysteresis with abrupt switching events that coincide, within experimental resolution, with the local switching of ferroelectric polarization. The large spontaneous polarization of the PZT film results in up to 500-fold amplification of the tunneling current upon ferroelectric switching. The magnitude of the effect is subject to electrostatic control via ferroelectric switching, suggesting possible applications in ultrahigh-density data storage and spintronics.
Maksymovych, Petro [ORNL; Jesse, Stephen [ORNL; Yu, Pu [University of California, Berkeley; Ramesh, R. [University of California, Berkeley; Baddorf, Arthur P [ORNL; Kalinin, Sergei V [ORNL
Multivent effects in a large scale boiling water reactor pressure suppression system
The steam-driven GKSS pressure suppression test facility, which contains 3 full scale vent pipes, has been used for 5 years to investigate the postulated loss-of-coolant accident in a Mark II and Type 69 boiling water reactor. Using the results from several of these tests, wetwell boundary load data (peak pressures and spectral power) during the chugging stage, have been evaluated for sparse pool response (one and two vents in the three vent pool) and for full pool response (one, two, or three vent operation in pools of constant wetwell pool area per vent). The sparse pool results indicate the pool-system, chug event boundary loads are strongly dependent on wetwell pool area per vent, with the load increasing with decreasing area. The full pool results show a substantial increase in the pool-system, chug event boundary loads upon a change from single cell to double cell operation; only minor change occurs in going from double to triple cell operation.
McCauley, E.W.; Aust, E.; Schwan, H.
Property:Water Type | Open Energy Information
Type Type Jump to: navigation, search Property Name Water Type Property Type String Pages using the property "Water Type" Showing 25 pages using this property. (previous 25) (next 25) 1 1.5-ft Wave Flume Facility + Freshwater + 10-ft Wave Flume Facility + Freshwater + 11-ft Wave Flume Facility + Freshwater + 2 2-ft Flume Facility + Freshwater + 3 3-ft Wave Flume Facility + Freshwater + 5 5-ft Wave Flume Facility + Freshwater + 6 6-ft Wave Flume Facility + Freshwater + A Alden Large Flume + Freshwater + Alden Small Flume + Freshwater + Alden Tow Tank + Freshwater + Alden Wave Basin + Freshwater + B Breakwater Research Facility + Freshwater + Bucknell Hydraulic Flume + Freshwater + C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + Freshwater +
Performance of a Counterflow Virtual Impactor in the NASA Icing Research Tunnel
A counterflow virtual impactor (CVI) designed for aircraft use was evaluated at the NASA Icing Research Tunnel in Cleveland, Ohio. Tests were conducted for tunnel speeds of 67 and 100 m s?1, for liquid water contents of 0.23–1.4 g m?3, and for a ...
C. H. Twohy; J. W. Strapp; M. Wendisch
Study of Cost Effective Large Advanced Pressurized Water Reactors that Employ Passive Safety Features
A report of DOE sponsored portions of AP1000 Design Certification effort. On December 16, 1999, The United States Nuclear Regulatory Commission issued Design Certification of the AP600 standard nuclear reactor design. This culminated an 8-year review of the AP600 design, safety analysis and probabilistic risk assessment. The AP600 is a 600 MWe reactor that utilizes passive safety features that, once actuated, depend only on natural forces such as gravity and natural circulation to perform all required safety functions. These passive safety systems result in increased plant safety and have also significantly simplified plant systems and equipment, resulting in simplified plant operation and maintenance. The AP600 meets NRC deterministic safety criteria and probabilistic risk criteria with large margins. A summary comparison of key passive safety system design features is provided in Table 1. These key features are discussed due to their importance in affecting the key thermal-hydraulic phenomenon exhibited by the passive safety systems in critical areas. The scope of some of the design changes to the AP600 is described. These changes are the ones that are important in evaluating the passive plant design features embodied in the certified AP600 standard plant design. These design changes are incorporated into the AP1000 standard plant design that Westinghouse is certifying under 10 CFR Part 52. In conclusion, this report describes the results of the representative design certification activities that were partially supported by the Nuclear Energy Research Initiative. These activities are unique to AP1000, but are representative of research activities that must be driven to conclusion to realize successful licensing of the next generation of nuclear power plants in the United States.
Winters, J. W.; Corletti, M. M.; Hayashi, Y.
Nanoscale heat conduction across tunnel junctions
?2005? Nanoscale heat conduction across tunnel junctions Y.May 2005? Nanoscale heat conduction across tunnel junctionsprevailing theory of heat conduction in highly disordered
Ju, Y. Sungtaek; Hung, M T; Carey, M J; Cyrille, M C; Childress, J R
Laws Envirosearch Institutional Controls NEPA Activities RCRA RQ*Calculator Water HSS Logo Water Laws Overview of water-related legislation affecting DOE sites Clean...
Developing a Practical Wind Tunnel Test Engineering Course for Undergraduate Aerospace Engineering Students
This thesis describes the development and assessment of an undergraduate wind tunnel test engineering course utilizing the 7ft by 10ft Oran W. Nicks Low Speed Wind Tunnel (LSWT). Only 5 other universities in the United States have a wind tunnel of similar size and none have an undergraduate wind tunnel test engineering course built around it. Many universities use smaller wind tunnels for laboratory instruction, but these experiments are meant to only demonstrate basic concepts. Students go beyond conceptual learning in this wind tunnel test engineering course and conduct real-world experiments in the LSWT. This course puts knowledge into practice and further prepares students whether continuing on to graduate school or industry. Course content mainly originates from the chapters in Low Speed Wind Tunnel Testing by Barlow, Rae, and Pope. This is the most comprehensive book that addresses the specific requirements of large scale, low speed wind tunnel testing. It is not a textbook for novices. The three experiments used in the course are modeled on actual experiments that were performed at the LSWT. They are exactly what a commercial entity would want performed although the time scale is drastically reduced because of class requirements. Students complete the course with a working knowledge of the requirements of large scale, low speed wind tunnel tests because they have successfully performed real-world tests and have performed data reduction that is needed for high-quality industrial tests.
Recla, Benjamin Jeremiah
Turbulence Spectra and Dissipation Rates in a Wind Tunnel Model of the Atmospheric Convective Boundary Layer
A model of the atmospheric convective boundary layer (CBL) is realized in the thermally stratified wind tunnel of the Institute of Hydrology and Water Resources, University of Karlsruhe. Further experimental results from this model are presented. ...
Rolf Kaiser; Evgeni Fedorovich
Amending constructed roadside and urban soils with large volume-based compost applications: effects on water quality
Mineral nutrients imported in composted dairy manure (CDM) and municipal biosolid (CMB) amendments for highway-rights-of-way and urban landscapes can pose a threat to surface water quality. Treatments were developed to evaluate recommendations for amending roadside and urban soils with compost at large volumebased rates. Texas Department of Transportation (TxDOT) recommendations were evaluated in 2002 and 2003. Municipal recommendations were evaluated in 2004. Treatments were imposed on 4 by 1.5-m field plots on a constructed soil with an 8.5% slope. Three TxDOT compost application methods were tested; incorporation at 25% by volume (CMT), topdressing over vegetation (GUC), and topdressing a 5-cm compost woodchip mix over bare soil (ECC). In 2003, a 12.5% CMT treatment was substituted for the GUC, and two contrasting composts were compared. In 2002, soil test phosphorus (STP) concentrations (mg kg-1) were 291, 360, 410, and 1921 mg kg-1 in the 0 to 5-cm layer of a course textured CMT, fine textured CMT, GUC, and ECC treatments, respectively using CDM. In 2003, STP concentrations were 264, 439, 496,623, 1115, and 2203 mg kg-1, in the 0 to 5-cm layer after incorporation of CDM and CMB at the 12.5 and 25% volume-based rates, and topdressing the 5-cm CDM- or CMB-woodchip mix over bare soil, respectively. In 2004, contrasting CMB products, relatively low or high in total phosphorus (TP) were incorporated into the soil at 12.5 and 25% by volume, or imported in transplanted sod at the 25% by volume rate. The STP concentrations were 87, 147, 180, 301, 322, and 544 mg kg-1, respective to the previously defined treatments. Runoff water from 14, 10, and 8 natural rain events was used to characterize nutrient and sediment transport in 2002, 2003, and 2004, respectively. Concentration of TDP in runoff water was highly variable for roadside treatments across rain events. Mass losses of TDP were similar after CDM or CMB were incorporated into the soil at 12.5 and 25% by volume. Compost incorporation was the most effective method for limiting TP loss in runoff. Roadway and urban soils are expected to contribute greater TP losses as P concentration increases in soils.
Hansen, Nels Edward
Quantum tunneling, quantum computing, and high temperature superconductivity
In this dissertation, I have studied four theoretical problems in quantum tunneling, quantum computing, and high-temperature superconductivity. I have developed a generally-useful numerical tool for analyzing impurity-induced resonant-state images observed with scanning tunneling microscope (STM) in high temperature superconductors. The integrated tunneling intensities on all predominant sites have been estimated. The results can be used to test the predictions of any tight-binding model calculation. I have numerically simulated two-dimensional time-dependent tunneling of a Gaussian wave packet through a barrier, which contains charged ions. We have found that a negative ion in the barrier directly below the tunneling tip can deflect the tunneling electrons and drastically reduce the probability for them to reach the point in the target plane directly below the tunneling tip. I have studied an infinite family of sure-success quantum algorithms, which are introduced by C.-R. Hu [Phys. Rev. A {\\bf 66}, 042301 (2002)], for solving a generalized Grover search problem. Rigorous proofs are found for several conjectures made by Hu and explicit equations are obtained for finding the values of two phase parameters which make the algorithms sure success. Using self-consistent Hartree-Fock theory, I have studied an extended Hubbard model which includes quasi-long-range Coulomb interaction between the holes (characterized by parameter V). I have found that for sufficiently large V/t, doubly-charged-antiphase-island do become energetically favored localized objects in this system for moderate values of U/t, thus supporting a recent conjecture by C.-R. Hu [Int. J. Mod. Phys. B {\\bf 17}, 3284 (2003)].
Wang, Qian
Propeller design optimization for tunnel bow thrusters in the bollard pull condition
Tunnel bow thrusters are often used by large ships to provide low-speed lateral maneuverability when docking. Required to provide high thrust while essentially at a standstill, the design point for these thrusters is the ...
Wilkins, James R., IV
Petrology and geochemistry of samples from bed-contact zones in Tunnel Bed 5, U12g-Tunnel, Nevada Test Site
This report summarizes the detailed geologic characterization of samples of bed-contact zones and surrounding nonwelded bedded tuffs, both within Tunnel Bed 5, that are exposed in the G-Tunnel complex beneath Rainier Mesa on the Nevada Test Site (NTS). Original planning studies treated the bed-contact zones in Tunnel Bed 5 as simple planar surfaces of relatively high permeability. Detailed characterization, however, indicates that these zones have a finite thickness, are depositional in origin, vary considerably over short vertical and horizontal distances, and are internally complex. Fluid flow in a sequence of nonwelded zeolitized ash-flow or bedded tuffs and thin intervening reworked zones appears to be a porous-medium phenomenon, regardless of the presence of layering. There are no consistent differences in either bulk composition or detailed mineralogy between bedded tuffs and bed-contact zones in Tunnel Bed 5. Although the original bulk composition of Tunnel Bed 5 was probably peralkaline, extensive zeolitization has resulted in a present peraluminous bulk composition of both bedded tuffs and bed-contact zones. The major zeolite present, clinoptilolite, is intermediate (Ca:K:Na = 26:35:39) and effectively uniform in composition. This composition is similar to that of clinoptilolite from the tuffaceous beds of Calico Hills above the static water level in hole USW G-1, but somewhat different from that reported for zeolites from below the static water level in USW G-2. Tunnel Bed 5 also contains abundant hydrous manganese oxides. The similarity in composition of the clinoptilolites from Tunnel Bed 5 and those above the static water level at Yucca Mountain indicates that many of the results of nuclide-migration experiments in Tunnel Bed 5 would be transferrable to zeolitized nonwelded tuffs above the static water level at Yucca Mountain.
Connolly, J.R.; Keil, K.; Mansker, W.L.; Allen, C.C.; Husler, J.; Lowy, R.; Fortney, D.R.; Lappin, A.R.
Resonant Tunneling Device Logic Circuits
This report is a summary of the activities in the field of resonant tunneling device circuit design. The presented work has been performed by the Department of Microelectronics of the University of Dortmund (UNIDO) and the Solid-State Electronics Department of the Gerhard-Mercator University of Duisburg (GMUD) during the first year of the Microelectronics Advanced Research Initiative projects ANSWERS (Autonomous Nanoelectronic Systems with Extended Replication and Signalling) and LOCOM (Logic Circuits with Reduced Complexity based on Devices with Higher Functionality). As part of the ANSWERS work-package the principal task of UNIDO is to investigate novel logic circuit architectures for resonant tunneling devices, to perform circuit simulations, and to specify the electrical device parameters. The basic device configuration is a monolithically integrated resonant tunneling diode heterostructure field-effect transistor (RTD-HFET). This device and the demonstrator circuits are fabricated by the LOCOM partner GMUD.
Christian Pacha; Peter Glösekötter; Karl Goser; Werner Prost; Uwe Auer; Franz-J. Tegude
Ivar Giaever, Tunneling, and Superconductors
Ivar Giaever, Tunneling, and Superconductors Ivar Giaever, Tunneling, and Superconductors Resources with Additional Information · Patents Ivar Giaever Courtesy of Rensselaer Polytechnic Institute 'Dr. Giaever received his engineering degree at the Norwegian Institute of Technology. After college, he emigrated to Canada, where he worked as a mechanical engineer with General Electric, and later transferred to GE's Development Center in Schenectady, N.Y. There, he shifted his interest to physics, and did graduate work at Rensselaer, receiving a Ph.D. in 1964. From 1958 to 1970, Dr. Giaever worked in the fields of thin films, tunneling, and superconductivity,'1 research that resulted in his receiving the Nobel Prize in Physics in 1973. '[I]n 1971, Dr. Giaever began studying the behavior of organic molecules at solid surfaces, and the interaction of cells with surfaces. In 1988, he became an Institute Professor of Science at Rensselaer.' 1
Report Tunneling Cost Reduction Study prepared for Fermilab
Fermi National Accelerator Laboratories has a need to review the costs of constructing the very long tunnels which would be required for housing the equipment for the proposed Very Large Hadron Collider (VLHC) project. Current tunneling costs are high, and the identification of potential means of significantly reducing them, and thereby helping to keep overall project costs within an acceptable budget, has assumed great importance. Fermilab has contracted with The Robbins Company to provide an up-to-date appraisal of tunneling technology, and to review the potential for substantially improving currently the state-of-practice performance and construction costs in particular. The Robbins Company was chosen for this task because of its long and successful experience in hard rock mechanical tunnel boring. In the past 40 years, Robbins has manufactured over 250 tunneling machines, the vast majority for hard rock applications. In addition to also supplying back-up equipment, Robbins has recently established a division dedicated to the manufacture of continuous conveying equipment for the efficient support of tunneling operations. The study extends beyond the tunnel boring machine (TBM) itself, and into the critical area of the logistics of the support of the machine as it advances, including manpower. It is restricted to proven methods using conventional technology, and its potential for incremental but meaningful improvement, rather than examining exotic and undeveloped means of rock excavation that have been proposed from time to time by the technical community. This is the first phase of what is expected to be a number of studies in increasing depth of technical detail, and as such has been restricted to the issues connected with the initial 34 kilometer circumference booster tunnel, and not the proposed 500 kilometer circumference tunnel housing the VLHC itself. The booster tunnel is entirely sited within low to medium strength limestone and dolomite formations, typical of the Chicago area. The rock is generally competent with widely spaced jointing, and slowdown of the operation for the installation of rock support is expected to be minimal. The tunneling system will have to be equipped with the necessary equipment for an efficient response to poor rock conditions however. Because the ground conditions are expected to be very favorable, a state-of-the-art TBM should have no difficulty in excavating at a high penetration rate of 10 meters per hour or more in rock of the average of the range of strengths stated to exist. Disc cutter changes will be few as the rock has very low abrasivity. However, experience has shown that overall tunneling rates are a relatively low percentage of the machine's penetration rate capability. Therefore the main focus of improvement is guaranteeing that the support systems, including mucking and advance of the utilities do not impede the operation. Improved mechanization of the support systems, along with automation where practicable to reduce manpower, is seen as the best means of raising the overall speed of the operation, and reducing its cost. The first phase of the study is mainly involved with establishing the baseline for current performance, and in identifying areas of improvement. It contains information on existing machine design concepts and provides data on many aspects of the mechanical tunneling process, including costs and labor requirements. While it contains suggestions for technical improvements of the various system, the time limitations of this phase have not permitted any detailed concept development. This should be a major part of the next phase.
Resonance tunneling spectroscopy of heteropoly compounds
The electron tunneling spectra of phosphomolybdic and phosphomolybdovanadic acids have been measured using a scanning tunneling microscope. A new mechanism of negative differential resistance (NDR) formation in tunneling nanocontacts is established, which is general for all systems featuring the Wannier-Stark localization effect. A two-center inelastic resonance tunneling model is constructed, which allows the values of both electron and vibrational energy parameters to be determined from the measured spectra.
Dalidchik, F. I., E-mail: email@example.com; Budanov, B. A.; Kolchenko, N. N.; Balashov, E. M.; Kovalevskii, S. A. [Russian Academy of Sciences, Semenov Institute of Chemical Physics (Russian Federation)
Tunable Compression of Wind Tunnel Data
Tunable Compression of Wind Tunnel Data. Summary: Measurements of pressures exerted by wind on buildings, as are ...
Dynamical tunneling in molecules: role of the classical resonances and chaos
In this letter we study dynamical tunneling in highly excited symmetric molecules. The role of classical phase space structures like resonances and chaos on the tunneling splittings are illustrated using the water molecule as an example. It is argued that the enhancements in the splittings due to resonances (near-integrable phase space) and due to chaos (mixed phase space) are best understood away from the fluctuations associated with avoided crossings. In particular we provide an essential difference between the two mechanisms in terms of high order perturbation theory. The analysis, apart from testing the validity of a perturbative approach, suggests such systems as prime candidates for studying dynamical tunneling.
Srihari Keshavamurthy
Watershed modeling using large-scale distributed computing in Condor and the Soil and Water Assessment Tool model
Models are increasingly being used to quantify the effects of best management practices (BMPs) on water quality. While these models offer the ability to study multiple BMP scenarios, and to analyze impacts of various management decisions on watershed ... Keywords: Condor, Conservation Effectiveness Assessment Program, Lincoln Lake, Soil and Water Assessment Tool Model, TeraGrid, best management practices
Margaret W Gitau; Li-Chi Chiang; Mohamed Sayeed; Indrajeet Chaubey
Simulating scanning tunneling microscope measurements
One of the largest problems in scanning tunneling microscopy design is noise control. It is the burden of the designer to determine if money should be used to build a floating room for vibration isolation or for top-of-the-line ...
Venkatachalam, Vivek
Macroscopic quantum tunneling with decoherence
The tunneling probability for a system modelling macroscopic quantum tunneling is computed. We consider an open quantum system with one degree of freedom consisting of a particle trapped in a cubic potential interacting with an environment characterized by a dissipative and a diffusion parameter. A representation based on the energy eigenfunctions of the isolated system, i. e. the system uncoupled to the environment, is used to write the dynamical master equation for the reduced Wigner function of the open quantum system. This equation becomes very simple in that representation. The use of the WKB approximation for the eigenfunctions suggests an approximation which allows an analytic computation of the tunneling rate, in this real time formalism, when the system is initially trapped in the false ground state. We find that the decoherence produced by the environment suppresses tunneling in agreement with results in other macroscopic quantum systems with different potentials. We confront our analytical predictions with an experiment where the escape rate from the zero voltage state was measured for a current-biased Josephson junction shunted with a resistor.
Esteban Calzetta; Enric Verdaguer
Wind Tunnel Study of Turbulent Flow Structure in the Convective Boundary Layer Capped by a Temperature Inversion
Experiments on simulating the atmospheric convective boundary layer (CBL), capped by a temperature inversion and affected by surface shear, were carried out in the thermally stratified wind tunnel of the Institute of Hydrology and Water Resources,...
Evgeni Fedorovich; Rolf Kaiser; Matthias Rau; Erich Plate
Photon Aided and Inhibited Tunneling of Photons
In the light of the interest in the transport of single photons in arrays of waveguides, fiber couplers, photonic crystals, etc., we consider the quantum mechanical process of the tunneling of photons through evanescently or otherwise coupled structures. We specifically examine the issue of tunneling between two structures when one structure already contains few photons. We demonstrate the possibility of both photon aided and inhibited tunneling of photons. The Bosonic nature of photons enhances the tunneling probability. We also show how the multiphoton tunneling probability can be either enhanced or inhibited due to the presence of photons. We find similar results for the higher order tunneling. Finally, we show that the presence of a squeezed field changes the nature of tunneling considerably.
liu, xuele
Meso- to Large-Scale Structure of Subducting Water in the Subtropical Gyre of the Eastern North Atlantic Ocean
As part of an observational study of ocean subduction, SeaSoar surveys were carried out following subducting water tagged by bobber floats during their deployment in the spring of 1991 and again in the fall of 1992 and spring of 1993. In the ...
Terrence M. Joyce; James R. Luyten; Alexander Kubryakov; Frank B. Bahr; Julie S. Pallant
Guidance on risk analysis and safety implications of a large liquefied natural gas (LNG) spill over water.
While recognized standards exist for the systematic safety analysis of potential spills or releases from LNG (Liquefied Natural Gas) storage terminals and facilities on land, no equivalent set of standards or guidance exists for the evaluation of the safety or consequences from LNG spills over water. Heightened security awareness and energy surety issues have increased industry's and the public's attention to these activities. The report reviews several existing studies of LNG spills with respect to their assumptions, inputs, models, and experimental data. Based on this review and further analysis, the report provides guidance on the appropriateness of models, assumptions, and risk management to address public safety and property relative to a potential LNG spill over water.
Wellman, Gerald William; Melof, Brian Matthew; Luketa-Hanlin, Anay Josephine; Hightower, Marion Michael; Covan, John Morgan; Gritzo, Louis Alan; Irwin, Michael James; Kaneshige, Michael Jiro; Morrow, Charles W.
Recrossing and Heavy-atom Tunneling in Common Organic Reactions
Non-statistical recrossing in ketene cycloadditions with alkenes, heavy-atom tunneling and the mechanism of the decarboxylation of Mandelylthiamin is investigated in this dissertation. A combination of experimental kinetic isotope effects and theoretical models and kinetic isotope effects is utilized for this endeavor. This dissertation also describes how the use of quasiclassical dynamic trajectories, microcanonical RRKM calculations, and canonical variational transition state theory in combination with small-curvature tunneling approximations is utilized to help advance our research methodology to better understand mechanism. In the cycloaddition of dichloroketene with cis-2-butene, significant amounts of recrossing is observed using quasiclassical dynamic trajectories. An unusual inverse 13C intramolecular KIE lead us to investigate the role that heavy atoms play in non-statistical recrossing. More importantly, this discovery has uncovered a new phenomena of entropic intermediates that not only applies to ketene cycloadditions, but can also be applicable to other "concerted" reactions such as Diels-Alder reactions. The ring-opening of cyclopropylcarbinyl radical has revealed that heavy-atom tunneling plays a major role. The intramolecular 13C kinetic isotope effects for the ring-opening of cyclopropylcarbinyl radical were unprecedentedly large and in combination with theoretical predictions and multidimensional tunneling corrections, the role of tunneling in this reaction can be better understood. The mechanism decarboxylation of mandelylthiamin has been extensively studied in the literature. However, until the use of theoretically predicted KIEs and theoretical binding motifs the rate-limiting step of this reaction has been hotly debated. In this dissertation, a discussion of how the theoretical KIEs indicate the initial C-C bond as the rate-limiting step and chelating binding motifs of pyridinium and mandelylthiamin to explain the observed catalysis is given.
James, Ollie
Chaos regularization of quantum tunneling rates
Quantum tunneling rates through a barrier separating two-dimensional, symmetric, double-well potentials are shown to depend on the classical dynamics of the billiard trajectories in each well and, hence, on the shape of the wells. For shapes that lead to regular (integrable) classical dynamics the tunneling rates fluctuate greatly with eigenenergies of the states sometimes by over two orders of magnitude. Contrarily, shapes that lead to completely chaotic trajectories lead to tunneling rates whose fluctuations are greatly reduced, a phenomenon we call regularization of tunneling rates. We show that a random-plane-wave theory of tunneling accounts for the mean tunneling rates and the small fluctuation variances for the chaotic systems.
Pecora, Louis M.; Wu Dongho [Materials Physics and Sensors, US Naval Research Laboratory, Washington, DC 20375 (United States); Lee, Hoshik [Department of Physics, College of William and Mary, Williamsburg, Virginia 23187 (United States); Antonsen, Thomas; Lee, Ming-Jer; Ott, Edward [Physics and Electrical Engineering Departments, University of Maryland, College Park, Maryland 20742 (United States)
Space Institute Tunnel | Open Energy Information
Tunnel Tunnel Jump to: navigation, search Basic Specifications Facility Name Space Institute Tunnel Overseeing Organization University of Tennessee Hydrodynamic Testing Facility Type Tunnel Length(m) 1.5 Beam(m) 0.4 Depth(m) 0.5 Cost(per day) ~$1000 (Contact POC for estimate) Towing Capabilities Towing Capabilities None Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Velocity(m/s) 0.9 Recirculating Yes Wind Capabilities Wind Capabilities None Control and Data Acquisition Description Computer with National Instruments SCXI DAS Chassis Number of channels 32 Bandwidth(kHz) Varies with number of channels and specific module/board Cameras Yes Available Sensors Flow, Strain, Turbulence Data Generation Capability
Wind tunnel model testing of offshore platforms.
?? The purpose of this thesis is to highlight some of the areas of interest when it comes to wind tunnel experimenting of offshore platforms… (more)
Abrahamsen, Ida Sinnes
Background Study on nu_e Appearance from a nu_mu Beam in Very Long Baseline Neutrino Oscillation Experiments with a Large Water Cherenkov Detector
There is a growing interest in very long baseline neutrino oscillation experimentation using accelerator produced neutrino beam as a machinery to probe the last three unmeasured neutrino oscillation parameters: the mixing angle theta_13, the possible CP violating phase delta_CP and the mass hierarchy, namely, the sign of delta-m^2_32. Water Cherenkov detectors such as IMB, Kamiokande and Super-Kamiokande have shown to be very successful at detecting neutrino interactions. Scaling up this technology may continue to provide the required performance for the next generation of experiments. This report presents the latest effort to demonstrate that a next generation (> 100 kton) water Cherenkov detector can be used effectively for the rather difficult task of detecting nu_e events from the neutrino oscillation nu_mu -> nu_e despite the large expected potential background resulting from pi^0 events produced via neutral current interactions.
Chiaki Yanagisawa; Chang Kee Jung; Trung Le; Brett Viren
Yanagisawa, Chiaki; Le, Trung; Viren, Brett
Optical modulation in a resonant tunneling relaxation oscillator
We report high speed optical modulation in a resonant tunneling relaxation oscillator consisting of a resonant tunneling diode (RTD) integrated with a unipolar optical waveguide and incorporated in a package with a coplanar waveguide transmission line. When appropriately biased, the RTD can provide wide-bandwidth electrical gain. For wavelengths near the material band-edge, small changes of the applied voltage give rise to large, high-speed electro-absorption modulation of the light. We have observed optical modulation at frequencies up to 14 GHz, associated with sub harmonic injection locking of the RTD oscillation at the fundamental mode of the coplanar transmission line, as well as generation of 33 ps optical pulses due to relaxation oscillation.
Figueiredo, J M L; Boyd, A R; Ironside, C N
MHL Student Tunnel | Open Energy Information
Student Tunnel Student Tunnel Jump to: navigation, search Basic Specifications Facility Name MHL Student Tunnel Overseeing Organization University of Michigan Hydrodynamics Hydrodynamic Testing Facility Type Channel Length(m) 1.4 Beam(m) 0.4 Depth(m) 0.3 Cost(per day) $2000(+ Labor/Materials) Towing Capabilities Towing Capabilities None Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Velocity(m/s) 4.6 Recirculating No Wind Capabilities Wind Capabilities None Control and Data Acquisition Description Custom Data Acquisition System using National Instruments hardware; system compatible with Planing Hull and Floating Beam Dynamometers Number of channels 16 Bandwidth(kHz) 20 Cameras Yes Description of Camera Types Wide variety of analog & digital surface cameras; high speed above and underwater cameras
A 233 km tunnel for lepton and hadron colliders
A decade ago, a cost analysis was conducted to bore a 233 km circumference Very Large Hadron Collider (VLHC) tunnel passing through Fermilab. Here we outline implementations of e{sup +}e{sup -}, pp-bar , and {mu}{sup +}{mu}{sup -} collider rings in this tunnel using recent technological innovations. The 240 and 500 GeV e{sup +}e{sup -} colliders employ Crab Waist Crossings, ultra low emittance damped bunches, short vertical IP focal lengths, superconducting RF, and low coercivity, grain oriented silicon steel/concrete dipoles. Some details are also provided for a high luminosity 240 GeV e{sup +}e{sup -} collider and 1.75 TeV muon accelerator in a Fermilab site filler tunnel. The 40 TeV pp-bar collider uses the high intensity Fermilab p-bar source, exploits high cross sections for pp-bar production of high mass states, and uses 2 Tesla ultra low carbon steel/YBCO superconducting magnets run with liquid neon. The 35 TeV muon ring ramps the 2 Tesla superconducting magnets at 9 Hz every 0.4 seconds, uses 250 GV of superconducting RF to accelerate muons from 1.75 to 17.5 TeV in 63 orbits with 71% survival, and mitigates neutrino radiation with phase shifting, roller coaster motion in a FODO lattice.
Summers, D. J.; Cremaldi, L. M.; Datta, A.; Duraisamy, M.; Luo, T.; Lyons, G. T. [Dept. of Physics and Astronomy, University of Mississippi-Oxford, University, MS 38677 (United States)
A Simple Technique for Simultaneous Suspension of Multiple Drops in a Small Vertical Wind Tunnel
A simple technique is described by which multiple millimeter-size water drops can be simultaneously suspended in an air stream above the test section of a 12 × 12 cm cross section of a vertical wind tunnel. Horizontal profiles of the vertical air ...
A. K. Kamra; D. V. Ahire
Topological tunneling with Dynamical overlap fermions
Tunneling between different topological sectors with dynamical chiral fermions is difficult because of a poor mass scaling of the pseudo-fermion estimate of the determinant. For small fermion masses it is virtually impossible using standard methods. However, by projecting out the small Wilson eigenvectors from the overlap operator, and treating the correction determinant exactly, we can significantly increase the rate of topological sector tunneling and reduce substantially the auto-correlation time. We present and compare a number of different approaches, and advocate a method which allows topological tunneling even at low mass with little addition to the computational cost.
Nigel Cundy; Stefan Krieg; Thomas Lippert; Andreas Schaefer
Methods for the fabrication of thermally stable magnetic tunnel junctions
DOE Patents (OSTI)
Magnetic tunnel junctions and method for making the magnetic tunnel junctions are provided. The magnetic tunnel junctions are characterized by a tunnel barrier oxide layer sandwiched between two ferromagnetic layers. The methods used to fabricate the magnetic tunnel junctions are capable of completely and selectively oxidizing a tunnel junction precursor material using an oxidizing gas containing a mixture of gases to provide a tunnel junction oxide without oxidizing the adjacent ferromagnetic materials. In some embodiments the gas mixture is a mixture of CO and CO.sub.2 or a mixture of H.sub.2 and H.sub.2O.
Chang, Y. Austin (Middleton, WI); Yang, Jianhua J. (Madison, WI); Ladwig, Peter F. (Hutchinson, MN)
Soliton in a Well. Dynamics and Tunneling
We derive the leading order radiation through tunneling of an oscillating soliton in a well. We use the hydrodynamic formulation with a rigorous control of the errors for finite times.
V. Fleurov; A. Soffer
How big around is the tunnel at...
actually two linear accelerators linked by arcs at the ends. There is also a web-based tour of the accelerator that you might find entertaining. What we do in the tunnel could...
Dissociative recombination: Crossing and tunneling modes
This report discusses the process of dissociative reconsiderations. The particular topics covered are: Upper Limit to Rate Coefficient; Tunneling Dissociative Recombinations; and Signature of Polyatomic Ion Dissociative Recombination. 210 refs., 151 figs., 7 tabs.
Bates, D.R. [Queen`s Univ. of Belfast (United Kingdom)
Semiconductor tunnel junction with enhancement layer
The incorporation of a pseudomorphic GaAsSb layer in a runnel diode structure affords a new degree of freedom in designing runnel junctions for p-n junction device interconnects. Previously only doping levels could be varied to control the tunneling properties. This invention uses the valence band alignment band of the GaAsSb with respect to the surrounding materials to greatly relax the doping requirements for tunneling.
Klem, John F. (Sandia Park, NM); Zolper, John C. (Albuquerque, NM)
Smart bridges, smart tunnels: Transforming wireless sensor networks from research prototypes into robust engineering infrastructure
We instrumented large civil engineering infrastructure items, such as bridges and tunnels, with sensors that monitor their operational performance and deterioration. In so doing we discovered that commercial offerings of wireless sensor networks (WSNs) ... Keywords: Civil engineering, Deployment, Radio propagation, Realworld experience, Security, Wireless sensor networks
Frank Stajano; Neil Hoult; Ian Wassell; Peter Bennett; Campbell Middleton; Kenichi Soga
Hoosac tunnel geothermal heat source. Final report
The Hoosac Rail Tunnel has been analyzed as a central element in a district heating system for the City of North Adams. The tunnel has been viewed as a collector of the earth's geothermal heat and a seasonal heat storage facility with heat piped to the tunnel in summer from existing facilities at a distance. Heated fluid would be transported in winter from the tunnel to users who would boost the temperature with individual heat pumps. It was concluded the tunnel is a poor source of geothermal heat. The maximum extractable energy is only 2200 million BTU (20000 gallons of oil) at 58/sup 0/F. The tunnel is a poor heat storage facility. The rock conductivity is so high that 75% of the heat injected would escape into the mountain before it could be recaptured for use. A low temperature system, with individual heat pumps for temperature boost could be economically attractive if a low cost fuel (byproduct, solid waste, cogeneration) or a cost effective seasonal heat storage were available.
Not Available
Method of fabricating a solar cell with a tunnel dielectric layer
Methods of fabricating solar cells with tunnel dielectric layers are described. Solar cells with tunnel dielectric layers are also described.
Dennis, Tim; Harrington, Scott; Manning, Jane; Smith, David; Waldhauer, Ann
Fabrication of magnetic tunnel junctions with epitaxial and textured ferromagnetic layers
This invention relates to magnetic tunnel junctions and methods for making the magnetic tunnel junctions. The magnetic tunnel junctions include a tunnel barrier oxide layer sandwiched between two ferromagnetic layers both of which are epitaxial or textured with respect to the underlying substrate upon which the magnetic tunnel junctions are grown. The magnetic tunnel junctions provide improved magnetic properties, sharper interfaces and few defects.
Chang, Y. Austin (Middleton, WI); Yang, Jianhua Joshua (Madison, WI)
A Note on Real Tunneling Geometries
In the Hartle-Hawking ``no boundary'' approach to quantum cosmology, a real tunneling geometry is a configuration that represents a transition from a compact Riemannian spacetime to a Lorentzian universe. I complete an earlier proof that in three spacetime dimensions, such a transition is ``probable,'' in the sense that the required Riemannian geometry yields a genuine maximum of the semiclassical wave function.
S. Carlip
Water Heaters and Hot Water Distribution Systems
The effect on water and gas usage from cross-flow betweencontrols have on water and gas usage over a large number ofsystems, and their water and gas usage. Hourly schedules for
Lutz, Jim
Acid-resistant, water-stable MOFs with ultra-large 1D channels exhibiting biomimetic catalytic activity have been developed. In their Communication
with enzymelike catalytic properties and record-setting surface areas debuted in separate studies By Mitch Jacoby Classes Take Off Biodiesel From Sewage Sludge Water-Driven Micromotors Rocket Around Starting Salaries
Behmer, Spencer T.
A Prognostic Parameterization for the Subgrid-Scale Variability of Water Vapor and Clouds in Large-Scale Models and Its Use to Diagnose Cloud Cover
A parameterization for the horizontal subgrid-scale variability of water vapor and cloud condensate is introduced, which is used to diagnose cloud fraction in the spirit of statistically based cloud cover parameterizations. High-resolution cloud-...
Adrian M. Tompkins
URANIUM PROJECT WATER-SOLUBLE SUBSTANCES IN KVANEFJELD LUJAVRITE NOVEMBER 1982 Emil S0rensen #12 a sample of 14.000 tonnes was mined from a 900 m long tunnel about 150 m below surface level. During
Water and Energy Interactions
oil recovery involves the injection of large quantities ofbarrel of oil equivalent (2). Although large quantities ofvarying, quantities of often low-quality water (2, 32). Oil
McMahon, James E.
Charged fermions tunneling from regular black holes
We study Hawking radiation of charged fermions as a tunneling process from charged regular black holes, i.e., the Bardeen and ABGB black holes. For this purpose, we apply the semiclassical WKB approximation to the general covariant Dirac equation for charged particles and evaluate the tunneling probabilities. We recover the Hawking temperature corresponding to these charged regular black holes. Further, we consider the back-reaction effects of the emitted spin particles from black holes and calculate their corresponding quantum corrections to the radiation spectrum. We find that this radiation spectrum is not purely thermal due to the energy and charge conservation but has some corrections. In the absence of charge, e = 0, our results are consistent with those already present in the literature.
Sharif, M., E-mail: email@example.com; Javed, W., E-mail: email@example.com [University of the Punjab, Department of Mathematics (Pakistan)
Dynamical overlap fermions with increased topological tunnelling
We present two improvements to our previous dynamical overlap HMC algorithm. We introduce a new method of differentiating the eigenvectors of the Kernel operator, which removes an instability in the fermionic force. Secondly, by simulating part of the fermion determinant exactly, without pseudo-fermions, we are able to increase the rate of topological tunnelling by a factor of more than ten, reducing the auto-correlation.
N. Cundy; S. Krieg; T. Lippert; A Schaefer
PUREX storage tunnels waste analysis plan
Washington Administrative Code 173-303-300 requires that a facility develop and follow a written waste analysis plan which describes the procedures that will be followed to ensure that its dangerous waste is managed properly. This document covers the activities at the PUREX Storage Tunnels used to characterize and designate waste that is generated within the PUREX Plant, as well as waste received from other on-site sources.
Haas, C.R., Westinghouse Hanford
The Quantum Hydrodynamic Description of Tunneling
The quantum hydrodynamic approach is based on the de Broglie-Bohm formulation of quantum mechanics. The resulting fluid-like equations of motion describe the flow of probability and an accurate solution to these equations is equivalent to solving the time-dependent Schroedinger equation. Furthermore, the hydrodynamic approach provides new insight into the mechanisms as well as an alternative computational approach for treating tunneling phenomena. New concepts include well-defined 'quantum trajectories', 'quantum potential', and 'quantum force' all of which have classical analogues. The quantum potential and its associated force give rise to all quantum mechanical effects such as zero point energy, tunneling, and interference. A new numerical approach called the Iterative Finite Difference Method (IFDM) will be discussed. The IFDM is used to solve the set of non-linear coupled hydrodynamic equations. It is 2nd-order accurate in both space and time and exhibits exponential convergence with respect to the iteration count. The stability and computational efficiency of the IFDM is significantly improved by using a 'smart' Eulerian grid which has the same computational advantages as a Lagrangian or Arbitrary Lagrangian Eulerian (ALE) grid. The IFDM is also capable of treating anharmonic potentials. Example calculations using the IFDM will be presented which include: a one-dimensional Gaussian wave packet tunneling through an Eckart barrier, a one-dimensional bound-state Morse oscillator, and a two-dimensional (2D) model collinear reaction using an anharmonic potential energy surface. Approximate treatments of the quantum hydrodynamic equations will also be discussed which could allow scaling of the calculations to hundreds of degrees of freedom which is important for treating tunneling phenomena in condensed phase systems.
Kendrick, Brian K. [Los Alamos National Laboratory
Resonant tunneling diodes: Models and properties
The resonant tunneling diode (RTD) has been widely studied because of its importance in the field of nanoelectronic science and technology and its potential applications in very high speed/functionality devices and circuits. Even though much progress has been made in this regard, additional work is needed to realize the full potential of RTD's. As research on RTD's continues, we will try in this tutorial review to provide the reader with an overall and succinct picture of where we stand in this exciting field of research and to address the following questions: What makes RTD's so attractive? To what extent can RTD's be modeled for design purposes? What are the required and achievable device properties in terms of digital logic applications? To address these issues, we review the device operational principles, various modeling approaches, and major device properties. Comparisons among the various RTD physical models and major features of RTD's, resonant interband tunneling diodes, and Esaki tunnel diodes are presented. The tutorial and analysis provided in this paper may help the reader in becoming familiar with current research efforts, as well as to examine the important aspects in further RTD developments and their circuit applications.
Jian Ping Sun; George I. Haddad; Pinaki Mazumder; Joel N. Schulman
Name Name Address Place Zip Category Sector Telephone number...
Water Tunnel Penn Large Water Tunnel Sandia National Laboratories Hydrodynamics Sandia National Laboratories Hydrodynamics P O Box Albuquerque New Mexico Category Stubs Category...
Oxygen-Induced Symmetrization and Structural Coherency in Fe/MgO/Fe(001) Magnetic Tunnel Junctions
We present x-ray diffraction experiments and multiple-scattering calculations on the structure and transport properties of a Fe/MgO/Fe(001) magnetic tunnel junction (MTJ). Coherent growth of the top Fe electrode on the MgO spacer is observed only for Fe deposition in ambient oxygen atmosphere leading to a coherent and symmetric MTJ structure characterized by FeO layers at both Fe/MgO interfaces. This goes in parallel with calculations indicating large positive tunnel magnetoresistance (TMR) values in such symmetric junctions. The results have important implications for achieving giant TMR values.
Tusche, C.; Meyerheim, H.L.; Ernst, A.; Henk, J.; Bruno, P.; Kirschner, J. [Max-Planck-Institut fuer Mikrostrukturphysik, Weinberg 2, D-06120 Halle (Germany); Jedrecy, N. [Institut des NanoSciences de Paris, Universites Paris 6 et 7, et CNRS-UMR 7588, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Renaud, G. [CEA-Grenoble, 17 rue des Martyrs, F-38054 Grenoble (France)
Hydroelectricity for agriculture and hydroelectricity. Large volumes of waterElectricity Production Hydroelectricity The most common type
Using Daylight to Light the Access Zone of Road Tunnels
Using Daylight to Light the Access Zone of Road Tunnels Using Daylight to Light the Access Zone of Road Tunnels Speaker(s): Eliyahu Ne'eman Date: March 4, 2003 - 12:00pm Location: Bldg. 90 Lighting guides for roadway tunnels specify relatively high luminances for the "access zone" into the tunnel. They are needed to allow the eyes of the driver sufficient time to adapt during the short period of the transition from the outdoor natural daylight levels to the fairly low luminances along the main length of the tunnel. Usually, the necessary high luminances are provided by rows of costly luminaries which consume a lot of electricity during peak use periods and need a good deal of maintenance. To save some electric power, controls are used to dim the lighting on cloudy hours. Daylight has been used for the access zone in several tunnels around the
Geologic mapping of tunnels using photogrammetry: Camera and target positioning
A photogrammetric method has been developed by the US Geological Survey and the US Bureau of Reclamation for the use in geologic mapping of tunnels (drifts). The method requires photographing the tunnel walls and roof with a calibrated small-format camera to obtain stereo pairs of photos which are then oriented in an analytical stereo plotter for measurement of geologic features. The method was tested in G-tunnel at Rainier Mesa on the Nevada Test Site. Calculations necessary to determine camera and target positions and problems encountered during testing were used to develop a set of generic formulas that can be applied to any tunnel. 7 figs.
Coe, J.A. [Geological Survey, Denver, CO (United States); Dueholm, K.S. [Danmarks Tekniske Hoejskole, Lyngby (Denmark). Inst. of Surveying and Photogrammetry
Calculation of tunneling rates across a barrier with continuous potential
Here, approximate, but accurate expressions for calculation of wavefunctions and tunneling rates are obtained using the method of uniform asymptotic expansion.
Sina Khorasani
Conte Large Flume | Open Energy Information
Conte Large Flume Conte Large Flume Overseeing Organization United States Geological Survey, LSC Hydrodynamic Testing Facility Type Flume Length(m) 38.1 Beam(m) 6.1 Depth(m) 5.2 Cost(per day) Contact POC Towing Capabilities Towing Capabilities None Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Recirculating No Wind Capabilities Wind Capabilities None Control and Data Acquisition Description National Instruments LabView and other data acquisition systems Number of channels 12 Bandwidth(kHz) 44 Cameras Yes Number of Color Cameras 5 Description of Camera Types Conventional underwater video, 4; high speed (1000 fps), 1 Available Sensors Displacement, Flow, Pressure Range(psi), Thermal, Turbulence, Velocity Data Generation Capability
First-principles study of the critical thickness in asymmetric ferroelectric tunnel junctions
The absent critical thickness of fully relaxed asymmetric ferroelectric tunnel junctions is investigated by first-principles calculations. The results show that PbTiO{sub 3} thin film between Pt and SrRuO{sub 3} electrodes can still retain a significant and stable polarization down to thicknesses as small as 0.8 nm, quite unlike the case of symmetric ferroelectric tunnel junctions. We trace this surprising result to the generation of a large electric field by the charge transfer between the electrodes caused by their different electronic environments, which acts against the depolarization field and enhances the ferroelectricity, leading to the reduction, or even complete elimination, for the critical thickness.
Cai Mengqiu [State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan 410083 (China); School of Physics and Microelectronics Science, Hunan University, Changsha 410082, Hunan (China); State Key Laboratory of Optoelectronic Materials and Technologies, Zhongshan University, Guangzhou 510275, Guangdong (China); Du Yong; Huang Boyun [State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan 410083 (China)
Competition between cotunneling, Kondo effect, and direct tunneling in discontinuous high-anisotropy magnetic tunnel junctions
The transition between Kondo and Coulomb blockade effects in discontinuous double magnetic tunnel junctions is explored as a function of the size of the CoPt magnetic clusters embedded between AlO{sub x} tunnel barriers. A gradual competition between cotunneling enhancement of the tunneling magnetoresistance (TMR) and the TMR suppression due to the Kondo effect has been found in these junctions, with both effects having been found to coexist even in the same sample. It is possible to tune between these two states with temperature (at a temperature far below the cluster blocking temperature). In addition, when further decreasing the size of the CoPt clusters, another gradual transition between the Kondo effect and direct tunneling between the electrodes takes place. This second transition shows that the spin-flip processes found in junctions with impurities in the barrier are in fact due to the Kondo effect. A simple theoretical model able to account for these experimental results is proposed.
Ciudad D.; Arena D.; We, Z.-C.; Hindmarch, A.T.; Negusse, E.; Han, X.-F.Han; Marrows, C.H.
Physics of Supercooling of Thin Water Skins Covering Gyrating Hailstones
Liquid water skins on spongy deposits of hailstones that grow while gyrating in a wind tunnel environment, have been routinely observed to be supercooled at the water skin–air interface to as low as ?5°C and more. The average water skin thickness ...
Roland List
Water Bugs
Bugs Bugs Nature Bulletin No. 221-A March 12, 1966 Forest Preserve District of Cook County Seymour Simon, President Roland F. Eisenbeis, Supt. of Conservation WATER BUGS It is fascinating to lie in a boat or on a log at the edge of the water and watch the drama that unfolds among the small water animals. Among the star performers in small streams and ponds are the Water Bugs. These are aquatic members of that large group of insects called the "true bugs", most of which live on land. Moreover, unlike many other types of water insects, they do not have gills but get their oxygen directly from the air. Those that do go beneath the surface usually carry an oxygen supply with them in the form of a shiny glistening sheath of air imprisoned among a covering of fine waterproof hairs. The common water insect known to small boys at the "Whirligig Bug" is not a water bug but a beetle.
Nonlinear Landau-Zener tunneling in coupled waveguide arrays
The possibility of direct observation of the nonlinear Landau-Zener tunneling effect with a device consisting of two waveguide arrays connected to a tilted reduced refractive index barrier is discussed. Numerical simulations on this realistic setup are interpreted via a simplified double-well system and different asymmetric tunneling scenarios are predicted varying just the injected beam intensity.
Khomeriki, Ramaz [Physics Department, Tbilisi State University, 3 Chavchavadze, 0128 Tbilisi (Georgia) and Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzerstrasse 38, D-01187 Dresden (Germany)
What is wrong in the current models of tunneling
In this paper we show that the conventional quantum-mechanical model of a non-resonant tunneling, as a subprocess of a one-dimensional completed scattering (OCS), is non-complete. It does not allow tracing the tunneling dynamics at all stages of scattering, what makes it impossible to resolve the tunneling time problem without coming into conflict with the (macro-)causality principle. As is shown, all timekeeping procedures to underlie the tunneling-time concepts and experiments presented in the tunneling time literature (TTL) fill this gap in the current description of the tunneling dynamics by 'self-evident' assumptions which are erroneous on closer inspection. We present the alternative model of the OCS, which allows tracing the tunneling dynamics at all stages of scattering and, as a consequence, is free from those paradoxes that flood the current TTL. By this model, among two fundamental velocity concepts of the wave dynamics -- the flow velocity and the group one -- only the former can be used to determine the velocity of tunneling particles in the barrier region.
Nikolay Chuprikov
Comparison Between Field Data and NASA Ames Wind Tunnel Data
The objective of this analysis is to compare the measured data from the NASA Ames wind tunnel experiment to those collected in the field at the National Wind Technology Center (NWTC) with the same turbine configuration. The results of this analysis provide insight into what measurements can be made in the field as opposed to wind tunnel testing.
Corbus, D.
Vibration-Assisted Electron Tunneling in C140 Transistors
We measure electron tunneling in transistors made from C140, a molecule with a mass?spring?mass geometry chosen as a model system to study electron-vibration coupling. We observe vibration-assisted tunneling at an energy corresponding to the stretching mode of C140. Molecular modeling provides explanations for why this mode couples more strongly to electron tunneling than to the other internal modes of the molecule. We make comparisons between the observed tunneling rates and those expected from the Franck?Condon model. When electrons travel through molecules, vibrational modes of the molecules can affect current flow. Molecular-vibrationassisted tunneling was first measured in the 1960s using devices whose tunnel barriers contained many molecules. 1 Recently, effects of vibrations in single molecules have been measured using scanning tunneling microscopes, 2 singlemolecule transistors, 3,4 and mechanical break junctions. 5 Theoretical considerations suggest that different regimes may exist depending on whether tunneling electrons occupy resonant energy levels on the molecule, and also on the * Corresponding author.
A. N. Pasupathy; J. Park; C. Chang; A. V. Soldatov; S. Lebedkin; R. C. Bialczak; J. E. Grose; L. A. K. Donev; J. P. Sethna; D. C. Ralph; P. L. Mceuen
Langley 16-Ft. Transonic Tunnel Pressure Sensitive Paint System
This report describes the NASA Langley 16-Ft. Transonic Tunnel Pressure Sensitive Paint (PSP) System and presents results of a test conducted June 22-23, 2000 in the tunnel to validate the PSP system. The PSP system provides global surface pressure measurements ...
Sprinkle Danny R.; Obara Clifford J.; Amer Tahani R.; Leighty Bradley D.; Carmine Michael T.; Burkett Cecil G.; Sealey Bradley S.
Long-term behaviour of twin tunnels in London clay
-state settlement RT, RTi Tunnel radius, and initial value S Settlement s Deviatoric stress tensor xxxi CONTENTS sŻ Deviatoric stress tensor stated relative to rotated yield surface axis Sintc , S int cmid Additional Scmax(ss) due to twin-tunnel interaction...
Laver, Richard George
Saving Money in Reno's Wind Tunnels | Department of Energy
Money in Reno's Wind Tunnels Money in Reno's Wind Tunnels Saving Money in Reno's Wind Tunnels June 28, 2010 - 5:14pm Addthis Located in one of Reno's natural wind tunnels, City Hall proved to be the perfect location for one of the city's nine new wind turbines. | Photo courtesy of the City of Reno Located in one of Reno's natural wind tunnels, City Hall proved to be the perfect location for one of the city's nine new wind turbines. | Photo courtesy of the City of Reno On the street level in Reno, it may be easy to forget that every time the breeze blows off the Truckee River and past the 17-story City Hall, the town is quietly saving money. But the $11,000 the city is expected to save each year from wind power will be a friendly reminder. Installed in early June, the two 1.5-kilowatt wind
Saving Money in Reno's Wind Tunnels Saving Money in Reno's Wind Tunnels Saving Money in Reno's Wind Tunnels June 28, 2010 - 5:14pm Addthis Located in one of Reno's natural wind tunnels, City Hall proved to be the perfect location for one of the city's nine new wind turbines. | Photo courtesy of the City of Reno Located in one of Reno's natural wind tunnels, City Hall proved to be the perfect location for one of the city's nine new wind turbines. | Photo courtesy of the City of Reno On the street level in Reno, it may be easy to forget that every time the breeze blows off the Truckee River and past the 17-story City Hall, the town is quietly saving money. But the $11,000 the city is expected to save each year from wind power will be a friendly reminder. Installed in early June, the two 1.5-kilowatt wind
ST/EL and ST/CV services for TI2 & TI8 LHC injection tunnels
This paper describes the ST/EL and ST/CV services for TI2 & TI8 LHC injection tunnels. The cooling and ventilation part describes the requirements for design and installation of more than 10 km of pipeline that is going to be laid down in the tunnels. Main operating parameters as well as manufacture procedures are explained. Preliminary work schedule with the cost estimate is also presented. Electrical power will be distributed from the LHC side and the SPS side for the machine and the general services. All power converters will be installed on surface buildings. The link between the main bend converters and the main bend magnets will be realised with water-cooled cables. Rest of the magnets will be cabled by using conventional copper and aluminium cables. Due to long lengths of the injection tunnels a dry 18kV transformer will be installed in TJ8 to serve the general services for TI8. The same will apply to TI2 by installing a transformer at the bottom of the PMI2 shaft.
Akhtar, S; CERN. Geneva. ST Division
Energy Water Linkage: Projected Water Needs
June 2004 Executive Summary Thermoelectric generation requires large volumes of water, primarily for cooling. An analysis was conducted to estimate the demand...
Tunnel-injection GaN quantum dot ultraviolet light-emitting diodes
We demonstrate a GaN quantum dot ultraviolet light-emitting diode that uses tunnel injection of carriers through AlN barriers into the active region. The quantum dot heterostructure is grown by molecular beam epitaxy on AlN templates. The large lattice mismatch between GaN and AlN favors the formation of GaN quantum dots in the Stranski-Krastanov growth mode. Carrier injection by tunneling can mitigate losses incurred in hot-carrier injection in light emitting heterostructures. To achieve tunnel injection, relatively low composition AlGaN is used for n- and p-type layers to simultaneously take advantage of effective band alignment and efficient doping. The small height of the quantum dots results in short-wavelength emission and are simultaneously an effective tool to fight the reduction of oscillator strength from quantum-confined Stark effect due to polarization fields. The strong quantum confinement results in room-temperature electroluminescence peaks at 261 and 340 nm, well above the 365 nm bandgap of bulk GaN. The demonstration opens the doorway to exploit many varied features of quantum dot physics to realize high-efficiency short-wavelength light sources.
Verma, Jai; Kandaswamy, Prem Kumar; Protasenko, Vladimir; Verma, Amit; Grace Xing, Huili; Jena, Debdeep [Department of Electrical Engineering, University of Notre Dame, Indiana 46556 (United States)] [Department of Electrical Engineering, University of Notre Dame, Indiana 46556 (United States)
Construction monitoring activities in the ESF starter tunnel
In situ design verification activities am being conducted in the North Ramp Starter Tunnel of the Yucca Mountain Project Exploratory Studies Facility. These activities include: monitoring the peak particle velocities and evaluating the damage to the rock mass associated with construction blasting, assessing the rock mass quality surrounding the tunnel, monitoring the performance of the installed ground support, and monitoring the stability of the tunnel. In this paper, examples of the data that have been collected and preliminary conclusions from the data are presented.
Pott, J. [Sandia National Labs., Albuquerque, NM (United States); Carlisle, S. [Agapito (J.F.T.) and Associates, Inc., Grand Junction, CO (United States)
Thermal/mechanical analyses of G-Tunnel field experiments at Rainier Mesa, Nevada
Analysis methods (models) are currently being developed to support thermal, mechanical, and thermomechanical aspects of repository design and performance assessment of the candidate Yucca Mountain high-level nuclear waste site. Credibility of these models, and therefore of design and performance analyses, will in part be determined through comparison of calculated and measured response (validation) for large-scale field experiments. This paper discusses the models being developed, the rationale behind the model development, and analyses of experiments performed at G-Tunnel and planned as part of site characterization at Yucca Mountain. 25 refs., 21 figs.
Bauer, S.J.; Costin, L.S.; Chen, E.P.; Tillerson, J.R.
[Scanning tunnelling microscopy and spectroscopy of ceramic grain boundaries]. [Annual report, September 1992--September 1993
Objective is to study the local geometric and electronic structure at grain boundaries in oxides; this was motivated by the potential to use STM and tunneling spectroscopy on semiconducting ceramics. In order to understand the imaging of low conductivity materials, a number of transition metal oxides were examined: ZnO, TiO{sub 2}. Spatial resolution limits are considered. Conductance profiles across silicon grain boundaries are compared with those across more complex SrTiO{sub 3} grain boundaries. Calculations of space charge in complex oxides are presented. A SEM/STM was constructed which operates in ultrahigh vacuum and has large scale positioning capability (> 1 cm).
Evidence of strong-coupling superconductivity in CaC{sub 6} from tunneling spectroscopy.
Tunneling in CaC{sub 6} crystals reproducibly reveals superconducting gaps {Delta} of 2.3 {+-} 0.2 meV that are {approx}40% larger than reported earlier. In an isotropic s-wave scenario, that puts CaC{sub 6} into the class of very strongly coupled superconductors, since 2{Delta}/kT{sub c} {approx} 4.6, implying that soft Ca phonons are primarily involved in the superconductivity. This conclusion explains the relatively large Ca isotope effect found recently for CaC{sub 6}, but it could also signal a strong anisotropy in the electron-phonon interaction.
Kurter, C.; Ozyuzer, L.; Mazur, D.; Zasadzinski, J. F.; Rosenmann, D.; Claus, H.; Hinks, D. G.; Gray, K. E.; Materials Science Division; Illinois Inst. Tech.; Izmir Inst. Tech.
Reexamination of Riming Electrification in a Wind Tunnel
Riming electrification experiments have been conducted in a wind tunnel, focusing on the substantial difference in results reported by Takahashi in 1978 and by Jayaratne et al. in 1983. Three critical regimes were selected, differing in ...
Tsutomu Takahashi; Kuniko Miyawaki
Response of continuous pipelines to tunnel induced ground deformations
This thesis develops analytical solutions for estimating the bending moments and axial loads in a buried pipeline due to ground movements caused by tunnel construction in soft ground. The solutions combine closed-form, ...
Ieronymaki, Evangelia S
Hybrid high-temperature superconductor-semiconductor tunnel diode
We report the demonstration of hybrid high-Tc-superconductor-semiconductor tunnel junctions, enabling new interdisciplinary directions in condensed matter research. The devices were fabricated by our newly-developed mechanical bonding technique, resulting in high-Tc-semiconductor planar junctions acting as superconducting tunnel diodes. Tunneling-spectra characterization of the hybrid junctions of Bi2Sr2CaCu2O8+{\\delta} combined with bulk GaAs, or a GaAs/AlGaAs quantum well, exhibits excess voltage and nonlinearity - in good agreement with theoretical predictions for a d-wave superconductor-normal material junction, and similar to spectra obtained in scanning tunneling microscopy. Additional junctions are demonstrated using Bi2Sr2CaCu2O8+{\\delta} combined with graphite or Bi2Te3. Our results pave the way for new methods in unconventional superconductivity studies, novel materials and quantum technology applications.
Alex Hayat; Parisa Zareapour; Shu Yang F. Zhao; Achint Jain; Igor G. Savelyev; Marina Blumin; Zhijun Xu; Alina Yang; G. D. Gu; Harry E. Ruda; Shuang Jia; R. J. Cava; Aephraim M. Steinberg; Kenneth S. Burch
Superluminal tunneling of microwaves in smoothly varying transmission lines
Tunneling of microwaves through a smooth barrier in a transmission line is considered. In contrast to standard wave barriers, we study the case where the dielectric permittivity is positive, and the barrier is caused by the inhomogeneous dielectric profile. It is found that reflectionless, superluminal tunneling can take place for waves with a finite spectral width. The consequences of these findings are discussed, and an experimental setup testing our predictions is proposed.
Shvartsburg, A B; Brodin, G; Stenflo, L
Report on Produced Water
water is the largest volume by-product or waste stream associated with oil and gas exploration and production. The cost of managing such a large volume of water is a key...
Brookhaven and the Large Hadron Collider
Brookhaven & the Large Hadron Collider Brookhaven & the Large Hadron Collider Home News Brookhaven & ATLAS ATLAS ATLAS Calorimeter ATLAS Muon Spectrometer Construction Computing Upgrades RHIC & LHC Education LHC tunnel ATLAS detector ATLAS detector RACF BNL built superconducting magnets Brookhaven & the LHC The world's most powerful particle accelerator, the Large Hadron Collider (LHC) in Switzerland, powers unprecedented explorations of the deepest mysteries of the universe. In addition to serving as the U.S. host laboratory for the ATLAS experiment at the LHC, Brookhaven National Lab plays multiple roles in this international collaboration, from construction and project management to data storage and distribution. ATLAS rendering Brookhaven and ATLAS Brookhaven physicists and engineers are participating in one of the most
Getting Traffic Lights Talking to Improve Topeka's Traffic Tunnel |
Getting Traffic Lights Talking to Improve Topeka's Traffic Tunnel Getting Traffic Lights Talking to Improve Topeka's Traffic Tunnel Getting Traffic Lights Talking to Improve Topeka's Traffic Tunnel October 8, 2010 - 11:16am Addthis Topeka is using Recovery Act funding to resynchronize 22 traffic lights. | Photo by Linda Voss Topeka is using Recovery Act funding to resynchronize 22 traffic lights. | Photo by Linda Voss Lindsay Gsell The five-lane 21st street corridor in Topeka is a hub for restaurants, shopping and entertainment. "This is where everyone in Topeka goes to shop," says Topeka resident Linda Voss. In addition to food and fun, the one-mile corridor is home to seven traffic lights-and for drivers, a potential traffic stop every 754 feet, or a little more than two football fields. "The traffic signals are a challenge to time in this area," says Voss,
Development of the resource model for the Decision Aids for Tunneling (DAT)
The Decision Aids for Tunneling (DAT) are a computer based method with which distributions of tunnel construction time and cost as well as required and produced resources can be estimated considering uncertainties in ...
Min, Sangyoon, 1973-
Review and evaluation of the RELAP5YA computer code and the Vermont Yankee LOCA (Loss-of-Coolant Accident) licensing analysis model for use in small and large break BWR (Boiling Water Reactor) LOCAS
A review has been completed of the RELAP5YA computer code to determine its acceptability for performing licensing analyses. The review was limited to Boiling Water Reactor (BWR) reactor applications. In addition, a Loss-Of-Coolant Accident (LOCA) licensing analysis method, using the RELAP5YA computer code, has been reviewed. This method is applicable to the Vermont Yankee Nuclear Power Station to perform full break spectra LOCA and fuel cycle independent analyses. The review of the RELAP5YA code consisted of an evaluation of all Yankee Atomic Electric Company (YAEC) incorporated modifications to the RELAP5/MOD1 Cycle 18 computer code from which the licensing version of the code originated. Qualifying separate and integral effects assessment calculations were reviewed to evaluate the validity and proper implementation of the various added models. The LOCA licensing method was assessed by reviewing two RELAP5YA system input models and evaluating several small and large break qualifying transient calculations. A review of the RELAP5YA code modifications and their assessments, as well as the submitted LOCA licensing method, is given and the results of the review are provided.
Jones, J.L.
Collaborative Governance in the CALFED Program: Adaptive Policy Making for California Water
example: [Take a] large [water] agency and an agriculturalagency. [The large water agency would] like to tradehigh quality for low quality water because it blends and
Innes, Judith E.; Connick, Sarah; Kaplan, Laura; Booher, David E.
Results of pressurized-slot measurements in the G-Tunnel underground facility
A rock-mechanics field-testing program is underway at Sandia National Laboratories (SNL) as part of the YMP. SNL has the responsibility for assessing the repository design and performance as well as characterizing the geomechanical behavior of the rock. SNL has conducted field experiments in G-Tunnel in Rainier Mesa at the NTS, where tuffs similar to those at Yucca Mountain, the potential repository site, are found. Later experiments are planned as part of the YMP Exploratory Shaft investigations at Yucca Mountain. Major geomechanical factors in repository developments are determinations of the stress state and the deformability of the rock mass (described by the modulus of deformation). One feature of SNL`s rock-mechanics program was the development of a testing program for cutting thin slots in a jointed welded tuff and utilizing flatjacks for pressurizing these thin-slots on a relatively, large scale. Objectives in the pressurized-slot testing in G-Tunnel have been to apply and possibly improve methods for (1) utilizing the flatjack cancellation (FC) method for measuring stresses normal to the slot and (2) measuring the modulus of deformation of the jointed rock surrounding the slot. This paper discusses the results of field measurements in and around a single slot and evaluates potential applications and limitations. 10 refs., 1 fig., 4 tabs.
Zimmerman, R.M.; Mann, K.L.; Dodds, D.J.
A portable vacuum hammer seismic source for use in tunnel environments
Concern for the measurement of seismic refraction velocities in tunnel areas where cables, construction features, and other sensitive structures render the use of dynamite sources unwise, resulted in the design of a vacuum-driven impact system utilizing a 43-kg (94-lb) weight in a 2-m (6.5-ft) tube. The system is portable, quickly assembled and disassembled, and requires only standard electrical power, an air pressure supply, and a laboratory vacuum pump to operate. The maximum weight of any component is 84 kg (185 lb), the remaining components being significantly lighter. Tests in volcanic rock tunnels in Rainier Mesa at the Nevada Test Site indicate maximum energy generated by the system is in the SV wave. When the system was employed at angles other than vertical, a polarized SH mode was also observed. The hammer was used to obtain velocities in an in-hole survey in a 138-m horizontal hole drilled behind the flat face of the Red Hot chamber after the Red Hot nuclear detonation. A large decrease was observed in compressional velocity compared with pre-event values. Because 20 years have elapsed since the explosion, one cannot separate the effect of ground shock on lowering the velocity from possible effects of destressing around adjacent underground openings over this period.
Carroll, R.D.; Magner, J.E.
An apparatus for studying spallation neutrons in the Aberdeen Tunnel laboratory
In this paper, we describe the design, construction and performance of an apparatus installed in the Aberdeen Tunnel laboratory in Hong Kong for studying spallation neutrons induced by cosmic-ray muons under a vertical rock overburden of 611 meter water equivalent (m.w.e.). The apparatus comprises of six horizontal layers of plastic-scintillator hodoscopes for determining the direction and position of the incident cosmic-ray muons. Sandwiched between the hodoscope planes is a neutron detector filled with 650 kg of liquid scintillator doped with about 0.06% of Gadolinium by weight for improving the e?ciency of detecting the spallation neutrons. Performance of the apparatus is also presented.
S. C. Blyth; Y. L. Chan; X. C. Chen; M. C. Chu; R. L. Hahn; T. H. Ho; Y. B. Hsiung; B. Z. Hu; K. K. Kwan; M. W. Kwok; T. Kwok; Y. P. Lau; K. P. Lee; J. K. C. Leung; K. Y. Leung; G. L. Lin; Y. C. Lin; K. B. Luk; W. H. Luk; H. Y. Ngai; S. Y. Ngan; C. S. J. Pun; K. Shih; Y. H. Tam; R. H. M. Tsang; C. H. Wang; C. M. Wong; H. L. Wong; H. H. C. Wong; K. K. Wong; M. Yeh
Incompatibility of the tunneling limit with laser fields
The Schwinger limit refers to longitudinal electric fields that are sufficiently strong to "polarize the vacuum" into electron-positron pairs by a tunneling mechanism. Laser fields are transverse electromagnetic fields for which the Schwinger limit has no relevance. Longitudinal and transverse fields are fundamentally different because of the different values of the F^{{\\mu}{\
H. R. Reiss
Improved tunnel resistance of silvered-polymer mirrors
This report documents the research performed at the Solar Energy Research Institute during fiscal year (FY) 1991 to develop ways to prevent delamination failure (known as tunneling) of silvered-polymer reflector materials. Several promising approaches have been identified and demonstrated that substantially reduce such failures. These approaches include (1) use of Tedlar edge tape rather than the manufacturer-recommended ECP-244 tape, (2) thermal treatment of laminated reflector/substrate constructions, and (3) application of silver to the polymer film through an alternative deposition process. Approaches 1 and 2 offer readily available engineering solutions to the delamination problem. Approaches 2 and 3 provide tunnel resistance over the entire surface of the reflector material, including the edges. Tedlar (a polyvinyl fluoride from DuPont) tape is an opaque white tape available in different widths from 3M Company. The base material has demonstrated outstanding outdoor durability. Thermal treatment of ECP-305 laminated to substrate materials has demonstrated outstanding resistance to tunneling. Alternative silver deposition techniques such as sputtering (rather than thermal evaporation) offer increased resistance to tunneling. 15 refs., 10 figs.
Jorgensen, G.; Schissel, P.; Kennedy, C.; Shinton, Y.; Powell, D.; Siebarth, J.
Tunnel junction multiple wavelength light-emitting diodes
A multiple wavelength LED having a monolithic cascade cell structure comprising at least two p-n junctions, wherein each of said at least two p-n junctions have substantially different band gaps, and electrical connector means by which said at least two p-n junctions may be collectively energized; and wherein said diode comprises a tunnel junction or interconnect.
Olson, Jerry M. (Lakewood, CO); Kurtz, Sarah R. (Golden, CO)
A Cross-Platform for Tunnel Blast Design and Simulation
Digital Mine has become the inevitable development trend of the future mines. Blasting is a essential process during the exploration and development of practical mining engineering. The blasting always plays a direct influence on the efficiency of each ... Keywords: Digital Mine, Blasting parameters, Parameters design, Tunnel blast design, Cross-platform
Tingting Zhu; Chao Wang; Mingmin Zhang; Zhigeng Pan
Coherent resonant tunneling through an artificial molecule C. A. Stafford
Coherent resonant tunneling through an artificial molecule C. A. Stafford Fakulta¨t fu¨r Physik PRB 58C. A. STAFFORD, R. KOTLYAR, AND S. DAS SARMA #12;Coulomb blockade12 for C Cg to a ballistic /e 1 follows from the particle-hole symmetry of Eq. 1 . 7094 PRB 58C. A. STAFFORD, R. KOTLYAR, AND S
Stafford, Charles
High-Lift Flight Tunnel---Phase II Report
The High-Lift Flight Tunnel (HiLiFT) concept is a revolutionary approach to aerodynamic ground testing. This concept utilizes magnetic levitation and linear motors to propel an aerodynamic model through a tube containing a quiescent test medium. This ...
Lofftus David; Lund Thomas; Rote Donald
Laboratory and Wind Tunnel Evaluations of the Rosemount Icing Detector
The Rosemount model 871FA ice detector was evaluated during a number of laboratory and wind tunnel studies. The purpose of this evaluation was to determine the sensitivity of the detector to a variety of icing conditions and to determine its ...
Darrel Baumgardner; Alfred Rodi
Macroscopic quantum tunnelling in a current biased Josephson junction
We discuss in this work an attempt to answer experimentally the question: do macroscopic variables obey quantum mechanics. More precisely, this experiment deals with the question of quantum-mechanical tunnelling of a macroscopic variable, a subject related to the famous Schrodinger's cat problem in the theory of measurement.
Martinis, J.M.; Devoret, M.H.; Clarke, J.; Urbina, C.
Safety analysis of natural gas vehicles transiting highway tunnel
A safety analysis was performed to assess the relative hazard of compressed natural gas (CNG) fueled vehicles traveling on various tunnels and bridges in New York City. The study considered those hazards arising from the release of fuel from CNG vehicles ranging in size from a passenger sedan to a full size 53 passenger bus. The approach used was to compare the fuel hazard of CNG vehicles to the fuel hazard of gasoline vehicles. The risk was assessed by estimating the frequency of occurrence and the severity of the hazard. The methodology was a combination of analyzing accident data, performing a diffusion analysis of the gas released in the tunnel and determining the consequences of ignition. Diffusion analysis was performed using the TEMPEST code for various accident scenarios resulting in CNG release inside the Holland Tunnel. The study concluded that the overall hazard of CNG vehicles transiting a ventilated tunnel is less than the hazard from a comparable gasoline fueled vehicle. 134 refs., 23 figs., 24 tabs.
Shaaban, S.H.; Zuzovsky, M.; Anigstein, R.
A multiple wavelength LED having a monolithic cascade cell structure comprising at least two p-n junctions, wherein each of said at least two p-n junctions have substantially different band gaps, and electrical connector means by which said at least two p-n junctions may be collectively energized; and wherein said diode comprises a tunnel junction or interconnect. 5 figs.
Olson, J.M.; Kurtz, S.R.
Pressurized Icing Tunnel for Graupel, Hail and Secondary Raindrop Production
The closed-circuit icing wind tunnel with pressure control serves for experiments on the growth and melting of ice particles, such as graupel and hailstones, and the observation of shedding of rain-sized drops by growing and melting hailstones. ...
Roland List; G. B. Lesins; F. García-García; D. B. McDonald
The Drinking Water Security and Safety Amendments of 2002: Is America's Drinking Water Infrastructure Safer Four Years Later?
pumping station, or water intake could deprive large areasthe pre-treatment and water intake part of the system; and 'around intakes; intruder resis- tant fences enclosing water
Shermer, Steven D.
Polarization-engineered GaN/InGaN/GaN tunnel diodes
We report on the design and demonstration of polarization-engineered GaN/InGaN/GaN tunnel junction diodes with high current density and low tunneling turn-on voltage. Wentzel-Kramers-Brillouin (WKB) calculations were used to model and design tunnel junctions with narrow bandgap InGaN-based barrier layers. N-polar p-GaN/In0.33Ga0.67N/n-GaN heterostructure tunnel diodes were grown using molecular beam epitaxy. Efficient zero bias tunneling turn-on with a high current density of 118 A/cm2 at a reverse bias of 1V, reaching a maximum current density up to 9.2 kA/cm2 were obtained. These results represent the highest current density reported in III-nitride tunnel junctions, and demonstrate the potential of III-nitride tunnel devices for a broad range of optoelectronic and electronic applications.
Sriram Krishnamoorthy; Digbijoy N. Nath; Fatih Akyol; Pil Sung Park; Michele Esposto; Siddharth Rajan
Augmentation of SPICE for Simulation of Circuits Containing Resonant Tunneling Diodes
This paper describes the incorporation of an accurate physics-based model of the resonant tunneling diode (RTD) into Berkeley SPICE version 3F5 and addresses the related direct current (dc) and transient convergence problems caused by the negative differential resistance (NDR) and the exponential nature of the device characteristics. To circumvent the dc convergence problems, a new continuation technique using artificial parameter embedding and a current limiting algorithm are proposed. The studies made in this paper have shown that these techniques are superior to the in-built continuation methods of SPICE, such as Gmin-stepping and Source-stepping, for a large number of circuits of varying sizes. To improve transient convergence performance, the following three algorithms are added to SPICE: a modified forced-convergence algorithm, a new time-step adjustment algorithm, and a modified device voltage prediction algorithm.
Mayukh Bhattacharya; et al.
Accuracy of the Frensley inflow boundary condition for Wigner equations in simulating resonant tunneling diodes
In this paper, the accuracy of the Frensley inflow boundary condition of the Wigner equation is analyzed in computing the I-V characteristics of a resonant tunneling diode (RTD). It is found that the Frensley inflow boundary condition for incoming electrons holds only exactly infinite away from the active device region and its accuracy depends on the length of contacts included in the simulation. For this study, the non-equilibrium Green's function (NEGF) with a Dirichlet to Neumann mapping boundary condition is used for comparison. The I-V characteristics of the RTD are found to agree between self-consistent NEGF and Wigner methods at low bias potentials with sufficiently large GaAs contact lengths. Finally, the relation between the negative differential conductance (NDC) of the RTD and the sizes of contact and buffer in the RTD is investigated using both methods.
Jiang Haiyan [Department of Applied Mathematics, Beijing Institute of Technology, Beijing 100081 (China); Department of Mathematics and Statistics, University of North Carolina at Charlotte, Charlotte, NC 28223-0001 (United States); Cai Wei, E-mail: email@example.com [Department of Mathematics and Statistics, University of North Carolina at Charlotte, Charlotte, NC 28223-0001 (United States); Tsu, Raphael [Department of Electrical and Computer Engineering, University of North Carolina at Charlotte, Charlotte, NC 28223-0001 (United States)
In-situ tuff water migration/heater experiment: experimental plan
Tuffs on the Nevada Test Site (NTS) are currently under investigation as a potential isolation medium for heat-producing nuclear wastes. The National Academy of Sciences has concurred in our identification of the potentially large water content ({le}40 vol %) of tuffs as one of the important issues affecting their suitability for a repository. This Experimental Plan describes an in-situ experiment intended as an initial assessment of water generation/migration in response to a thermal input. The experiment will be conducted in the Grouse Canyon Welded Tuff in Tunnel U12g (G-Tunnel) located in the north-central region of the NTS. While the Grouse Canyon Welded Tuff is not a potential repository medium, it has physical, thermal, and mechanical properties very similar to those tuffs currently under consideration and is accessible at depth (400 m below the surface) in an existing facility. Other goals of the experiment are to support computer-code and instrumentation development, and to measure in-situ thermal properties. The experimental array consists of a central electrical heater, 1.2 m long x 10.2 cm diameter, surrounded by three holes for measuring water-migration behavior, two holes for measuring temperature profiles, one hole for measuring thermally induced stress in the rock, and one hole perpendicular to the heater to measure displacement with a laser. This Experimental Plan describes the experimental objectives, the technical issues, the site, the experimental array, thermal and thermomechanical modeling results, the instrumentation, the data-acquisition system, posttest characterization, and the organizational details.
Johnstone, J.K.
A Model for the Behavior of Magnetic Tunnel Junctions
A magnetic tunnel junction is a device that changes its electrical resistance with a change in an applied magnetic field. A typical junction consists of two magnetic electrodes separated by a nonmagnetic insulating layer. The magnetizations of the two electrodes can have two possible extreme configurations, parallel and antiparallel. The antiparallel configuration is observed to have the higher measured resistance and the parallel configuration has the lower resistance. To switch between these two configurations a magnetic field is applied to the device which is primarily used to change the orientation of the magnetization of one electrode usually called the free layer, although with sufficient high magnetic field the orientation of the magnetizations of both of the electrodes can be changed. The most commonly used models for describing and explaining the electronic behavior of tunnel junctions are the Simmons model and the Brinkman model. However, both of these models were designed for simple, spin independent tunneling. The Simmons model does not address the issue of applied magnetic fields nor does it address the form of the electronic band structure in the metallic electrodes, including the important factor of spin polarization. The Brinkman model is similar, the main difference between the two models being the shape of the tunneling barrier potential between the two electrodes. Therefore, the research conducted in this thesis has developed a new theoretical model that addresses these important issues starting from basic principles. The main features of the new model include: the development of equations for true spin dependent tunneling through the insulating barrier, the differences in the orientations of the electrode magnetizations on either side of the barrier, and the effects of the density of states function on the behavior of the junction. The present work has explored densities of states that are more realistic than the simplified free electron density of states function, and has developed an exact analytic solution for the case of an electron band of finite width. The approach taken in this thesis easily allows extension to cases where the band structure is different on either side of the barrier (known as heterojunctions) which are of greater interest in real magnetic tunnel junction devices rather than the simple, identical band structure devices.
Bryan John Baker
Low-Frequency Electromagnetic Backscatter from Buried Tunnels
This progress report is submitted under a contract between the Special Project Office of DARPA and Lawrence Livermore National Laboratory. The Project Manager at DARPA is Dr. Michael Zatman. Our purpose under this contract is to investigate interactions between electromagnetic waves and a class of buried targets located in multilayered media with rough interfaces. In this report, we investigate three preliminary problems. In each case our specific goal is to understand various aspects of the electromagnetic wave interaction mechanisms with targets in layered media. The first problem, discussed in Section 2, is that of low-frequency electromagnetic backscattering from a tunnel that is cut into a lossy dielectric half-space. In this problem, the interface between the upper (free space) region and the lower (ground) region is smooth. The tunnel is assumed to be a cylindrical free-space region of infinite extent in its axial direction and with a diameter that is small in comparison to the free-space wavelength. Because its diameter is small, the tunnel can be modeled as a buried ''wire'' described by an equivalent impedance per unit length. In Section 3 we extend the analysis to include a statistically rough interface between the air and ground regions. The interface is modeled as a random-phase screen. Such a screen reduces the coherent power in a plane wave that is transmitted through it, scattering some of the total power into an incoherent field. Our analysis of this second problem quantifies the reduction in the coherent power backscattered from the buried tunnel that is caused by the roughness of the air-ground interface. The problem of low-frequency electromagnetic backscattering from two buried tunnels, parallel to each other but at different locations in the ground, is considered in Section 4. In this analysis, we wish to determine the conditions under which the presence of more than one tunnel can be detected via backscattering. Section 5 concludes the report with a summary of the investigations discussed herein and recommendations for future work on problems of this class.
Casey, K; Pao, H
NIST Technology Innovation Program Announces New R&D ...
... The nation's economy depends critically on a large and complex civil infrastructure of water pipelines, roads, bridges and tunnels. ...
Distribution of Water in Hailstones
A large number of photographs of thin sections of quenched hailstones have been studied to determine the most common patterns of water distribution within hailstones. The way in which water is distributed throughout the hailstone determines which ...
Petr Chýlek; B. R. D. Gupta; Nancy C. Knight; Charles A. Knight
A Wind Tunnel and Theoretical Study of the Melting Behavior of Atmospheric Ice Particles. I: A Wind Tunnel Study of Frozen Drops of Radius < 500 ?m
A study has been made on the melting behavior of frozen drops suspended freely at terminal velocity in the UCLA Cloud Tunnel. The relative humidity of the air ranged between 25 and 95%. The warming rates of the tunnel air stream ranged from 2 to ...
R. Rasmussen; H. R. Pruppacher
Small Corrections to the Tunneling Phase Time Formulation
After reexamining the above barrier diffusion problem where we notice that the wave packet collision implies the existence of {\\em multiple} reflected and transmitted wave packets, we analyze the way of obtaining phase times for tunneling/reflecting particles in a particular colliding configuration where the idea of multiple peak decomposition is recovered. To partially overcome the analytical incongruities which frequently rise up when the stationary phase method is adopted for computing the (tunneling) phase time expressions, we present a theoretical exercise involving a symmetrical collision between two identical wave packets and a unidimensional squared potential barrier where the scattered wave packets can be recomposed by summing the amplitudes of simultaneously reflected and transmitted wave components so that the conditions for applying the stationary phase principle are totally recovered. Lessons concerning the use of the stationary phase method are drawn.
Alex E. Bernardini
Hanford facility dangerous waste permit application, PUREX storage tunnels
The Hanford Facility Dangerous Waste Permit Application is considered to be a single application organized into a General Information Portion (document number DOE/RL-91-28) and a Unit-Specific Portion. The scope of the Unit-Specific Portion is limited to Part B permit application documentation submitted for individual, operating treatment, storage, and/or disposal units, such as the PUREX Storage Tunnels (this document, DOE/RL-90-24). Both the General Information and Unit-Specific portions of the Hanford Facility Dangerous Waste Permit Application address the content of the Part B permit application guidance prepared by the Washington State Department of Ecology (Ecology 1996) and the US Environmental Protection Agency (40 Code of Federal Regulations 270), with additional information needs defined by the Hazardous and Solid Waste Amendments and revisions of Washington Administrative Code 173-303. For ease of reference, the Washington State Department of Ecology alpha-numeric section identifiers from the permit application guidance documentation (Ecology 1996) follow, in brackets, the chapter headings and subheadings. A checklist indicating where information is contained in the PUREX Storage Tunnels permit application documentation, in relation to the Washington State Department of Ecology guidance, is located in the Contents Section. Documentation contained in the General Information Portion is broader in nature and could be used by multiple treatment, storage, and/or disposal units (e.g., the glossary provided in the General Information Portion). Wherever appropriate, the PUREX Storage Tunnels permit application documentation makes cross-reference to the General Information Portion, rather than duplicating text. Information provided in this PUREX Storage Tunnels permit application documentation is current as of April 1997.
Price, S.M.
The development of magnetic tunnel junction fabrication techniques
. The effect of grain size, shape, voltage bias, temperature, layer thickness and roughness should be understood and controllable, in order to produce reproducible junctions. The most problematic requirement has been that of low resistance. Magnetic tunnel... . The effect of roughness, aluminium thickness and voltage on the number of pinholes and weak-links per unit area was studied. High frequency testing of read heads at wafer level was performed with a network analyser. Design implications for read head...
Elwell, Clifford Alastair
The Drop-Size Response of the CSIRO Liquid Water Probe
The response of the CSIRO liquid water content (LWC) device to water drops of different sizes has been investigated in a wind tunnel. Two series of experiments were conducted. The first compared the probe-measured LWC of sprays with different ...
C. J. Biter; J. E. Dye; D. Huffman; W. D. King
Saving Water Saves Energy
Hot water use in households, for showers and baths as wellas for washing clothes and dishes, is a major driver of household energyconsumption. Other household uses of water (such as irrigatinglandscaping) require additional energy in other sectors to transport andtreat the water before use, and to treat wastewater. In California, 19percent of total electricity for all sectors combined and 32 percent ofnatural gas consumption is related to water. There is a criticalinterdependence between energy and water systems: thermal power plantsrequire cooling water, and water pumping and treatment require energy.Energy efficiency can be increased by a number of means, includingmore-efficient appliances (e.g., clothes washers or dishwashers that useless total water and less heated water), water-conserving plumbingfixtures and fittings (e.g., showerheads, faucets, toilets) and changesin consumer behavior (e.g., lower temperature set points for storagewater heaters, shorter showers). Water- and energy-conserving activitiescan help offset the stress imposed on limited water (and energy) suppliesfrom increasing population in some areas, particularly in drought years,or increased consumption (e.g., some new shower systems) as a result ofincreased wealth. This paper explores the connections between householdwater use and energy, and suggests options for increased efficiencies inboth individual technologies and systems. Studies indicate that urbanwater use can be reduced cost-effectively by up to 30 percent withcommercially available products. The energy savings associated with watersavings may represent a large additional and largely untappedcost-effective opportunity.
McMahon, James E.; Whitehead, Camilla Dunham; Biermayer, Peter
Energy Basics: Microhydropower Water Conveyance and Filters
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Large-Scale Hydropower Microhydropower Water Conveyance &...
Investigation of Data Quality for Wind Tunnel Internal Balance Testing
Achieving high quality, consistency, and testing efficiency in wind tunnel tests using internal balances is accomplished through the use of new testing methods, analysis of data output, and standardized documentation of test procedures at the Texas A&M Low Speed Wind Tunnel. The wind tunnel is capable of performing internal balance testing on models that experience less than 500 pounds of normal force. Testing has shown less than a 3% mean flow variation with the sting mount installed and a turbulence intensity of less than 0.25%. Documentation of procedures and check- lists for installation of internal balance testing equipment and test execution provide higher efficiency and consistency during a test. A step-by-step examination of the data analysis routines and associated uncertainty equations show uncertainty in the force and moment coefficients for the Mark XIII internal balance to be approximately ± 0.05 and ± 0.02, respectively. Quantifying the uncertainty of the primary output parameters and showing repeatability of the data within the defined uncertainty limits achieved higher quality results.
Hidore, John Preston
oil, natural gas, and coal bed methane. Argonne Natl. Lab. ,gallons of water (31). Coal-bed methane, the availability ofnatural gas production. Coal-bed methane produces large, but
Solar Water Heater Basics | Department of Energy
Solar Water Heater Basics Solar Water Heater Basics August 19, 2013 - 3:01pm Addthis Illustration of an active, closed loop solar water heater. A large, flat panel called a flat...
Solar Water Heaters | Department of Energy
Solar Water Heaters Solar Water Heaters August 19, 2013 - 3:01pm Addthis Illustration of an active, closed loop solar water heater. A large, flat panel called a flat plate...
Water Management Planning
water efficiency water efficiency at Federal sites Background The Federal Energy Management Program (FEMP) sponsored a water assessment at the Y-12 National Security Complex (Y-12) located in Oak Ridge, Tennessee, during fiscal year 2010. Driven by mandated water reduction goals of Executive Orders 13423 and 13514, the objective of the water assessment was to develop a comprehensive understanding of the current water-consuming applications and equipment at Y-12 and to identify key areas for water efficiency improvements. The water-assessment team learned key lessons from the Y-12 assessment. Therefore, the aim of this document is to share these key lessons to help other large process-driven sites at the Department of Energy (DOE) and beyond develop a comprehensive
On the Relation between Perfect Tunneling and Band Gaps for SNG Metamaterial Structures
In this article we have proposed a compact classification of isotropic and homogenous single negative (SNG) electromagnetic metamaterial based perfect tunneling unit cells. This has been made by means of the band gap theories and properties of the arrays made up of these unit cells. Based on their reported characteristics, we have proposed new structures that simultaneously show perfect tunneling band and complete band gap (CBG - omni directional stop band for both polarizations). Besides, we have identified perfect tunneling which can be considered as "phase shifted perfect tunneling". Several interesting and new phenomena like Complete Perfect Tunneling (CPT - omni-directional perfect tunneling for both polarizations), Band Gap Shifting, CBG in Double Positive (DPS) material range, etc. have been reported with proper physical and mathematical explanations.
Mahdy, M R C; Shawon, Jubayer; Al-Quaderi, Golam Dastegir; Matin, M A
Baker-Barry Tunnel Lighting: Evaluation of a Potential GATEWAY Demonstrations Project
The U.S. Department of Energy (DOE) is evaluating the Baker-Barry Tunnel as a potential GATEWAY Demonstrations project for deployment of solid-state lighting (SSL) technology. The National Park Service (NPS) views this project as a possible proving ground and template for implementation of light-emitting diode (LED) luminaires in other NPS tunnels, thereby expanding the estimated 40% energy savings from 132 MWh/yr for this tunnel to a much larger figure national
Tuenge, Jason R.
Facility Closure Report for T-Tunnel (U12t), Area 12, Nevada Test Site, Nevada
This Facility Closure Report (FCR) has been prepared to document the actions taken to permanently close the remaining accessible areas of U12t-Tunnel (T-Tunnel) in Area 12 of the Nevada Test Site (NTS). The closure of T-Tunnel was a prerequisite to transfer facility ownership from the Defense Threat Reduction Agency (DTRA) to the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO). Closure of the facility was accomplished with the cooperation and concurrence of both NNSA/NSO and the Nevada Division of Environmental Protection (NDEP). The purpose of this FCR is to document that the closure of T-Tunnel complied with the closure requirements specified in the Facility Closure Plan for N- and T-Tunnels Area 12, Nevada Test Site (Appendix D) and that the facility is ready for transfer to NNSA/NSO. The Facility Closure Plan (FCP) is provided in Appendix D. T-Tunnel is located approximately 42 miles north of Mercury in Area 12 of the NTS (Figure 1). Between 1970 and 1987, T-Tunnel was used for six Nuclear Weapons Effects Tests (NWETs). The tunnel was excavated horizontally into the volcanic tuffs of Rainier Mesa. The T-Tunnel complex consists of a main access drift with two NWET containment structures, a Gas Seal Plug (GSP), and a Gas Seal Door (GSD) (Figure 2). The T-Tunnel complex was mothballed in 1993 to preserve the tunnel for resumption of testing, should it happen in the future, to stop the discharge of tunnel effluent, and to prevent unauthorized access. This was accomplished by sealing the main drift GSD.
NSTec Environmental Restoration
MISTY ECHO Tunnel Dynamics Experiment--Data report: Volume 1; Yucca Mountain Site Characterization Project
Tunnel damage resulting from seismic loading is an important issue for the Yucca Mountain nuclear waste repository. The tunnel dynamics experiment was designed to obtain and document ground motions, permanent displacements, observable changes in fracture patterns, and visible damage at ground motion levels of interest to the Yucca Mountain Project. Even though the maximum free-field loading on this tunnel was 28 g, the damage observed was minor. Fielding details, data obtained, and supporting documentation are reported.
Phillips, J.S.; Luke, B.A.; Long, J.W.; Lee, J.G.
MISTY ECHO tunnel dynamics experiment data report; Volume 2, Appendices: Yucca Mountain Site Characterization Project
Scanning tunneling optical resonance microscopy applied to indium arsenide quantum dot structures.
??The technique of Scanning Tunneling Optical Resonance Microscopy (STORM) has been investigated for use on nanostructures. It has been demonstrated as a viable technique to… (more)
Byrnes, Daniel P.
How Does Law Affect Finance? An Examination of Financial Tunneling in an Emerging Market
How Does Law Affect Finance? An Examination of FinancialWilliam Davidson Institute. How Does Law Affect Finance? Anfinancial tunneling, Prior work does not distinguish between
Black, Bernard; Atanasov, Vladimir; Ciccotello, Conrad S.; Gyoshev, Stanley B.
Optimization of light emitting diodes based on bipolar double-barrier resonant-tunneling structures
A bipolar double-barrier resonant-tunneling light emitting diode will have maximum emitted light intensity if (1) electrons and holes simultaneously resonant-tunnel into the quantum well, (2) the charge carriers are entirely trapped in the well as the ... Keywords: Poisson equation, Schrodinger equation, automated computer code, bipolar double-barrier RTD structures, charge carriers, chemical compositions, doping profiles, electroluminescence, electroluminescence spectrum profile, electron-hole recombination, electron-hole recombination rate, geometric structures, light emitting diodes, near zero-field condition, optimisation, quantum well, resonant tunnelling diodes, resonant-tunneling LED, semiconductor device models, semiconductor quantum wells, temperature stability, theoretical modeling, thermal stability
A. Kindlihagen; K. A. Chao; M. Willander; J. Genoe
EE2, Regrown InGaAs Tunnel Junctions for TFETs - Programmaster ...
CBr4 and elemental Si were used as the dopant sources in the MBE ... Current-voltage (I-V) characteristics of regrown tunnel junctions on the ...
Vital Alert's C1000 mine and tunnel radios use magnetic induction...
Vital Alert's C1000 mine and tunnel radios use magnetic induction, advanced digital communications techniques and ultra-low frequency transmission to wirelessly provide...
Water Quality
Water Quality Water Quality We protect water quality through stormwater control measures and an extensive network of monitoring wells and stations encompassing groundwater, surface...
Interaction-induced fractional Bloch and tunneling oscillations
We study the dynamics of few interacting bosons in a one-dimensional lattice with dc bias. In the absence of interactions the system displays single-particle Bloch oscillations. For strong interaction the Bloch oscillation regime re-emerges with fractional Bloch periods which are inversely proportional to the number of bosons clustered into a bound state. The interaction strength affects the oscillation amplitude. Excellent agreement is found between numerical data and a composite particle dynamics approach. For specific values of the interaction strength, a particle will tunnel from the interacting cloud to a well-defined distant lattice location.
Khomeriki, Ramaz [Max Planck Institute for the Physics of Complex Systems, Noethnitzer Strasse 38, D-01187 Dresden (Germany); Physics Department, Tbilisi State University, Chavchavadze 3, 0128 Tbilisi (Georgia); Krimer, Dmitry O.; Haque, Masudul; Flach, Sergej [Max Planck Institute for the Physics of Complex Systems, Noethnitzer Strasse 38, D-01187 Dresden (Germany)
Tunneling through a parabolic barrier viewed from Wigner phase space
We analyze the tunneling of a particle through a repulsive potential resulting from an inverted harmonic oscillator in the quantum mechanical phase space described by the Wigner function. In particular, we solve the partial differential equations in phase space determining the Wigner function of an energy eigenstate of the inverted oscillator. The reflection or transmission coefficients $R$ or $T$ are then given by the total weight of all classical phase space trajectories corresponding to energies below, or above the top of the barrier given by the Wigner function.
D. M. Heim; W. P. Schleich; P. M. Alsing; J. P. Dahl; S. Varro
Results from Point Contact Tunnelling Spectroscopy and Atomic Layer Deposition
We have shown previously that magnetic niobium oxides can influence the superconducting density of states at the surface of cavity-grade niobium coupons. We will present recent results obtained by Point Contact Tunneling spectroscopy (PCT) on coupons removed from hot and cold spots in a niobium cavity, as well as a comparative study of magnetic oxides on mild baked/unbaked electropolished coupons. We will also describe recent results obtained from coated cavities, ALD films properties and new materials using Atomic Layer Deposition (ALD).
Proslier, Th. [Illinois Institute of Technology; Zasadzinski, J. [Illinois Institute of Technology; Ciovati, Gianluigi [JLAB; Kneisel, Peter K. [JLAB; Elam, J. W. [ANL; Norem, J. [ANL; Pellin, M. J. [ANL
Environmental quality indexing of large industrial development alternatives using AHP
Two industrial development alternatives have been proposed for the East Coast of Iceland in order to strengthen its socio-economic basis. The favoured option is to build a large aluminium smelter, which requires massive hydropower development in the nearby highlands. Another viable option is the construction of a 6-million-ton oil refinery, following the planned exploitation of the Timan Pechora oil reserves in the Russian Arctic. A third 'fictitious' alternative could be general development of existing regional industry and new knowledge-based industries, development of ecotourism, establishment of national parks, accompanied by infrastructure improvement (roads, tunnels, communications, schools, etc.). The three alternatives will have different environmental consequences. The controversial hydropower plant for the smelter requires a large water reservoir as well as considerable land disturbance in this unique mountain territory, considered to be the largest uninhabited wilderness in Western Europe. The aluminium smelter and the oil refinery will give rise to substantial increase of the greenhouse gas (GHG) emissions of the country (about 20%). Then there is potential environmental risk associated with the refinery regarding oil spills at sea, which could have disastrous impact on the fisheries industry. However, the oil refinery does not require any hydropower development, which is a positive factor. Finally, the third alternative could be defined as a ''green'' solution whereby the detrimental environmental consequences of the two industrial solutions are mostly avoided. In order to compare the three alternatives in an orderly manner, the analytic hierarchy process methodology of Saaty was applied to calculate the environmental quality index of each alternative, which is defined as a weighted sum of selected environmental and socio-economic factors. These factors are evaluated on a comparison basis, applying the AHP methodology, and the weights in the quality index summation are estimated in the same manner. Six persons with different backgrounds were asked to fill in the comparison matrices in order to reduce bias in the evaluation. The final results show that the two industrial alternatives come out poorly, i.e. with low quality indices, whereas the third pseudo-alternative, i.e. general development, with a considerably higher quality index, is certainly worth a further study.
Solnes, Julius
Wind Tunnel and Field Test of Three 2D Sonic Anemometers
Wind Tunnel and Field Test of Three 2D Sonic Anemometers Wiel Wauben R&D Information and Observation Technology, KNMI September 17, 2007 #12;#12;Wind Tunnel and Field Test of Three 2D Sonic.....................................................................................................1 2. Wind sensors
Stoffelen, Ad
Acoustic Survey of a 3/8-Scale Automotive Wind Tunnel
An acoustic survey that consists of insertion loss and flow noise measurements was conducted at key locations around the circuit of a 3/8-scale automotive acoustic wind tunnel. Descriptions of the test, the instrumentation, and the wind tunnel facility ...
Jr Earl R. Booth; Romberg Gary; Hansen Larry; Lutz Ron
A magnetic tunnel junction based zero standby leakage current retention flip-flop
Recently, a magnetic tunnel junction (MTJ), which is a strong candidate as a next-generation memory element, has been used not only as a memory cell but also in spintronics logic because of its excellent properties of nonvolatility, no silicon area occupation, ... Keywords: magnetic tunnel junction (MTJ) logic, nonvolatile flip-flop, retention flip-flop, spintronics logic
Kyungho Ryu, Jisu Kim, Jiwan Jung, Jung Pill Kim, Seung H. Kang, Seong-Ook Jung
Performing bitwise logic operations in cache using spintronics-based magnetic tunnel junctions
Recent exciting developments in the emerging field of spintronics have enabled rapid advances in spintronic devices such as magnetic tunnel junctions (MTJs). While MTJs are being primarily used as the basic devices in non-volatile memory, they have also ... Keywords: magnetic tunnel junctions, spintronic logic functions, spintronics logic in memory
Shruti Patil; David J. Lilja
Novel Resonant-Tunneling Multiple-Threshold Logic Circuit Based on Switching Sequence Detection
We present a novel multiple-threshold circuit using resonant-tunneling diodes (RTDs). The logic operation is based on detecting a switching sequence in the RTD circuit. This scheme enables us to increase the number of threshold voltages by more than ... Keywords: Resonant-tunneling diode, Multiple-threshold, analog-to-digital converter
Takao Waho; Kazufumi Hattori; Kouji Honda
Robust algorithm for tunnel closing in 3D volumetric objects based on topological characteristics of points
In this letter, we propose a robust, linear in time modification of Aktouf, Bertrand and Perroton's algorithm for tunnel (3D hole) closing in 3D volumetric objects. Our algorithm is insensitive to small distortions and branches. The algorithm has been ... Keywords: 3D image processing, Crack bridging, Skeletonisation, Topological numbers, Tunnel closing
Marcin Janaszewski; Micha? Postolski; Laurent Babout
Low-Speed Wind-Tunnel Investigation of the Stability and Control Characteristics
A wind-tunnel investigation was conducted in the Langley 12-Foot Low-Speed Tunnel to study the low-speed stability and control characteristics of a series of four flying wings over an extended range of angle of attack (-8\\deg to 48\\deg). Because of the ...
Fears Scott P.; Ross Holly M.; Moul Thomas M.
Large-Scale Aspects of the United States Hydrologic Cycle
A large-scale, gridpoint, atmospheric, hydrologic climatology consisting of atmospheric precipitable water, precipitation, atmospheric moisture flux convergence, and a residual evaporation for the conterminous United States is described. A large-...
John O. Roads; Shyh-C. Chen; Alexander K. Guetter; Konstantine P. Georgakakos
Large-Eddy Simulation: How Large is Large Enough?
The length scale evolution of various quantities in a clear convective boundary layer (CBL), a stratocumulus-topped boundary layer, and three radiatively cooled ("smoke cloud") convective boundary layers are studied by means of large-eddy ...
Stephan R. de Roode; Peter G. Duynkerke; Harm J. J. Jonker
Facility Closure Report for Tunnel U16a, Area 16, Nevada Test Site, Nevada
U16a is not listed in the Federal Facility Agreement and Consent Order. The closure of U16a was sponsored by the Defense Threat Reduction Agency (DTRA) and performed with the cooperation of the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office and the Nevada Division of Environmental Protection. This report documents closure of this site as identified in the DTRA Fiscal Year 2008 Statement of Work, Task 6.3. Closure activities included: · Removing and disposing of a shack and its contents · Disposing of debris from within the shack and in the vicinity of the tunnel entrance · Verifying that the tunnel is empty · Welding screened covers over tunnel vent holes to limit access and allow ventilation · Constructing a full-tunnel cross-section fibercrete bulkhead to prevent access to the tunnel Field activities were conducted from July to August 2008.
Combined Experiment Phase 1. [Horizontal axis wind turbines: wind tunnel testing versus field testing
How does wind tunnel airfoil data differ from the airfoil performance on an operating horizontal axis wind turbine (HAWT) The National Renewable Energy laboratory has been conducting a comprehensive test program focused on answering this question and understanding the basic fluid mechanics of rotating HAWT stall aerodynamics. The basic approach was to instrument a wind rotor, using an airfoil that was well documented by wind tunnel tests, and measure operating pressure distributions on the rotating blade. Based an the integrated values of the pressure data, airfoil performance coefficients were obtained, and comparisons were made between the rotating data and the wind tunnel data. Care was taken to the aerodynamic and geometric differences between the rotating and the wind tunnel models. This is the first of two reports describing the Combined Experiment Program and its results. This Phase I report covers background information such as test setup and instrumentation. It also includes wind tunnel test results and roughness testing.
Butterfield, C.P.; Musial, W.P.; Simms, D.A.
Topeka's "Green Light Tunnel" Saves Fuel and Time | Department of
Topeka's "Green Light Tunnel" Saves Fuel and Time Topeka's "Green Light Tunnel" Saves Fuel and Time Topeka's "Green Light Tunnel" Saves Fuel and Time April 22, 2011 - 1:50pm Addthis Topeka, Kansas, has activated the first of three key traffic corridors to receive a "green light tunnel," a real-time adaptive traffic signal system that synchronizes signals to create a series of green lights for motorists. The result is fewer stops, less travel time and -- most importantly -- a lot of saved gasoline. Sallie Glaize Project Officer, Office of Energy Efficiency & Renewable Energy What does this project do? Saves motorists in Topeka time and money. The first of three key traffic corridors in Topeka, Kansas has received a "green light tunnel," a real-time adaptive traffic signal system that
Hanford waste tanks - light at the end of the tunnel
The U.S. Department of Energy (DOE) faced several problems in its Hanford Site tank farms in the early nineties. It had 177 waste tanks, ranging in size from 55,000 to 1,100,000 gallons, which contained more than 55 million gallons of liquid and solid high-level radioactive waste (HLW) from a variety of processes. Unfortunately, waste transfer records were incomplete. Chemical reactions going on in the tanks were not totally understood. Every tank had high concentrations of powerful oxidizers in the form of nitrates and nitrites, and some tanks had relatively high concentrations of potential fuels that could react explosively with oxidizers. A few of these tanks periodically released large quantities of hydrogen and nitrous oxide, a mixture that was potentially more explosive than hydrogen and air. Both the nitrate/fuel and hydrogen/nitrous oxide reactions had the potential to rupture a tank exposing workers and the general public to unacceptably large quantities of radioactive material. One tank (241-C-106) was generating so much heat that water had to be added regularly to avoid thermal damage to the tank's concrete exterior shell. The tanks contained more than 250 million Curies of radioactivity. Some of that radioactivity was in the form of fissile plutonium, which represented a potential criticality problem. As awareness of the potential hazards grew, the public and various regulatory agencies brought increasing pressure on DOE to quantify the hazards and mitigate any that were found to be outside accepted risk guidelines. In 1990, then Representative, now Senator Ron Wyden (D-Oregon), introduced an amendment to Public Law 101-510, Section 3137, that required DOE to identify Hanford tanks that might have a serious potential for release of high-level waste.
The Influence of Strain Relaxation on the Electrical Properties of Submicron Si/SiGe Resonant-Tunneling Diodes
Resonant tunneling devices (RTDs) and resonant tunneling transistors (RTTs) are possible building blocks with increased functionality of future microelectronic circuits. These quantum devices can be made in the Si/SiGe system, which is compatible with ... Keywords: SiGe, resonant tunneling, strain relaxation
P. W. Lukey; J. Caro; T. Zijlstra; E. van der Drift; S. Radelaar
Properties of tunnel junctions with fluorocarbon dielectric barriers
Thesis. The electrical characteristics of In/I/In and In/I/Pb superconducting tunnel junctions have been studied in detail. Since In does not readily form pinhole free oxide layers, a thin insulating dielectric was formed on freshly deposited In film by passing an electric discharge through an atmosphere of fluorocarbon gas. Junctions were then completed by depositing a thin counter electrode of In or Pb. The same process was used to prepare high resistance junctions with Au as the base electrode; these were not however, studied in detail. In/I/In and In/I/Pb junctions were produced with resistances in the range 0.01 ohms to 10/sup 10/ ohms at liquid helium temperatures. Low resistance junctions exhibited nonlinear electrical characteristics associated with good quality oxide'' superconducting junctions including (a) the dc Josephson effcct, (b) quasiparticle tunneling characteristics. (c) phonon structure and (d) inelastic tunneling phenomena. The magnitude of the Josephson current for In/I/In junctions agreed to within a few percent of the value predicted by strong coupling theory. Current voltage (I-V) and first and second derivative curves for In/I/In and In/I/Pb were compared with curves for Al/I/In and Pb/I/Pb junctions. Discrepancies between the characteristics can be, for the most part, explained on the basis of existing theories of phonon mediated superconductivity using recent data from inelastic neutron scattering studies of In. Nonlinear structure at voltages below the phonon spectrum was observed and is most likely associated with Kohn singularities. At higher voltages, second derivative curves exhibited resonances characteristic of CH and OH impurities in the barrier as well as a complex spectrum associated with the vibrational spectrum of the fluorocarbon dielectric. To better characterize this dielectric, a variety of surface analytic techniques were used to determine the complex index of refraction, the chemical composition and chemical homogeneity of the barrier. I-V curves for high resistance junctions were used to determine the potential at the metal-insulator interface. (auth)
Jack, M.D.
Turbid water Clear water
: The submersible laser bathymetric (LBath) optical system is capable of simultaneously providing visual images- dynamical wing. This underwater package is pulled through the water by a single towed cable with fiber optic special high energy density optical fibers. A remote Pentium based PC also at the surface is used
Jaffe, Jules
Microbial Fuel Cells for Recycle of Process Water from ...
Large amounts of water are used in the processing of cellulosic biomass materials, so it is highly desirable to recycle used process water at the end ...
Water Phobic Powder Coatings Promise Breakthrough in Energy Saving ...
of algae on the surfaces of water systems. Water repellent coatings can be advantageously applied to large-scale structures, such as boat hulls,
Axis Ratios of Water Drops Levitated in a Vertical Wind Tunnel
The shapes of falling raindrops are often significantly altered by drop oscillations, complicating dual-polarization radar methods that rely on a predictable, monotonic variation of drop axis ratio ? with equivolume drop diameter d. This ...
B. K. Jones; J. R. Saylor
A Wind Tunnel Investigation of Interactions between Supercooled Precipitation-Size Water Drops
Laboratory experiments were performed to investigate interactions between small (400–900 ?m) precipitation-size drops at temperatures colder than 0°C. The investigation was accomplished by creating a light shower of supercooled drizzle drops in a ...
Robert R. Czys; Jeffrey K. Lew
Water | Department of Energy
Renewables » Water Renewables » Water Water EERE plays a key role in advancing America's "all of the above" energy strategy, leading a large network of researchers and other partners to deliver innovative technologies that will make renewable electricity generation cost-competitive with traditional sources of energy. EERE plays a key role in advancing America's "all of the above" energy strategy, leading a large network of researchers and other partners to deliver innovative technologies that will make renewable electricity generation cost-competitive with traditional sources of energy. Image of a buoy used for creating electricity from waves on the water. An american flag is attached to the top of the yellow buoy. The U.S. Department of Energy (DOE) leads the growing global effort to
Survey of radon and radon daughter concentrations in selected Rainier Mesa tunnels
A survey of radon and radon daughter concentrations (RDCs) in selected tunnels on Rainier Mesa at the Nevada Test Site (NTS) was conducted as a part of the underground testing program at NTS. Measurements were taken in three tunnels, N, T, and G. Results of preliminary measurements indicate that N and T Tunnels have low RDCs, i.e., 0.01 WL (working level) (3% of the EPA standard), with normal ventilation conditions. However, it was demonstrated that RDCs can rise to relatively high levels, i.e., 0.24 WL when ventilation rates are significantly lowered. The radon daughter concentrations measured in G Tunnel were an order of magnitude higher than those in N and T Tunnels. The average RDC in the rock mechanics drift (the ''worst-case'' location in G Tunnel) was 0.13 WL with a range from 0.07 WL to 0.23 WL. Elevated RDCs found in the rock mechanics drift of G Tunnel seemed to be attributable to a lower ventilation rate in conjunction with the more highly fractured nature of the ''welded tuff'' rock formation in which the incline drift was mined. By increasing the ventilation rate, a 60% reduction in RDCs from an average of 0.13 Wl to an average of 0.05 WL was achieved.
Fauver, D.N.
Water Intoxication
2008, May 14). Too much water raises seizure risk in babies.id=4844 9. Schoenly, Lorry. "Water Intoxication and Inmates:article/246650- overview>. 13. Water intoxication alert. (
Lingampalli, Nithya
Axial Ge/Si nanowire heterostructure tunnel FETs
The vapor-liquid-solid (VLS) growth of semiconductor nanowires allows doping and composition modulation along their axis and the realization of axial 1 D heterostructures. This provides additional flexibility in energy band-edge engineering along the transport direction which is difficult to attain by planar materials growth and processing techniques. We report here on the design, growth, fabrication, and characterization of asymmetric heterostructure tunnel field-effect transistors (HTFETs) based on 100% compositionally modulated Si/Ge axial NWs for high on-current operation and low ambipolar transport behavior. We discuss the optimization of band-offsets and Schottky barrier heights for high performance HTFETs and issues surrounding their experimental realization. Our HTFET devices with 10 nm PECVD SiN{sub x} gate dielectric resulted in a measured current drive exceeding 100 {mu}A/{mu}m (I/{pi}D) and 10{sup 5} I{sub on}/I{sub off} ratios.
Picraux, Sanuel T [Los Alamos National Laboratory; Daych, Shadi A [Los Alamos National Laboratory
A millikelvin scanning tunneling microscope with two independent scanning systems
We describe the design, construction and operation of a scanning tunneling microscope (STM) with two tips that can independently acquire simultaneous scans of a sample. The STM is mounted on a dilution refrigerator and the setup includes vibration isolation, rf-filtered wiring, an ultra high vacuum (UHV) sample preparation chamber and sample transfer mechanism. We present images and spectroscopy taken with superconducting Nb tips with the refrigerator at 35 mK that indicate that the effective temperature of our tips/sample is approximately 184 mK, corresponding to an energy resolution of 16 $\\mu$eV. Atomic resolution topographic images of an Au(100) surface taken with the inner and outer tips were found to have root mean square roughness of 1.75 $\\pm$ 0.01 pm and 3.55 $\\pm$ 0.03 pm respectively.
Roychowdhury, A; Anderson, J R; Lobb, C J; Wellstood, F C; Dreyer, M
Development of Ta-based Superconducting Tunnel Junction X-ray Detectors for Fluorescence XAS
We are developing superconducting tunnel junction (STJ) soft X-ray detectors for chemical analysis of dilute samples by fluorescence-detected X-ray absorption spectroscopy (XAS). Our 36-pixel Nb-based STJ spectrometer covers a solid angle {Omega}/4{pi} {approx} 10{sup -3}, offers an energy resolution of {approx}10-20 eV FWHM for energies up to {approx}1 keV, and can be operated at total count rates of {approx}10{sup 6} counts/s. For increased quantum efficiency and cleaner response function, we have now started the development of Ta-based STJ detector arrays. Initial devices modeled after our Nb-based STJs have an energy resolution below 10 eV FWHM for X-ray energies below 1 keV, and pulse rise time discrimination can be used to improve their response function for energies up to several keV. We discuss the performance of the Ta-STJs and outline steps towards the next-generation of large STJ detector arrays with higher sensitivity.
Friedrich, S; Drury, O; Hall, J; Cantor, R
Water Snakes
of Cook County George W. Dunne, President Roland F. Eisenbeis, Supt. of Conservation WATER SNAKES Contrary to popular belief, the Water Moccasin commonly known as the...
Pharmaceutical Waters
Table 3Â Â Â Water treatment process for water for injection (WFI)...deionization WFI production Evaporation still or vapor compression...
retort waters. Process waters are produced within the retortorganics. Process waters are produced in large quantities.Measurements Retort waters are co-produced with shale oil
Fox, J.P.
ScanningTunneling Luminescence of Grain Boundaries in Cu(In,Ga)Se2
At the Laboratory, photon emission in semiconductors has been mapped in the nanoscale using scanning tunneling microscopy (STM). In this Solar Program Review Meeting, we report on the latest results obtained in Cu(In,Ga)Se2 (CIGS) thin films by this adapted STM. Scanning tunneling luminescence (STL) spectroscopy suggests that photons are emitted near the surface of CIGS. STL is excited either by (1) diffusion of tunneling electrons and subsequent recombination with available holes in CIGS or (2) impact ionization by hot electrons. Which process becomes predominant depends on the voltage applied to the STM tip. Photon mapping shows electronically active, extended defects near the surface of CIGS thin films.
Romero, M. J.; Jiang, C.-S.; Al-Jassim, M. M.; Noufi, R.
the Large Aperture GRB Observatory
The Large Aperture GRB Observatory (LAGO) aims at the detection of high energy photons from Gamma Ray Bursts (GRB) using the single particle technique (SPT) in ground based water Cherenkov detectors (WCD). To reach a reasonable sensitivity, high altitude mountain sites have been selected in Mexico (Sierra Negra, 4550 m a.s.l.), Bolivia (Chacaltaya, 5300 m a.s.l.) and Venezuela (Merida, 4765 m a.s.l.). We report on the project progresses and the first operation at high altitude, search for bursts in 6 months of preliminary data, as well as search for signal at ground level when satellites report a burst.
Bertou, Xavier [Centro Atomico Bariloche (Argentina)
The Large Aperture GRB Observatory
The Large Aperture GRB Observatory (LAGO) is aiming at the detection of the high energy (around 100 GeV) component of Gamma Ray Bursts, using the single particle technique in arrays of Water Cherenkov Detectors (WCD) in high mountain sites (Chacaltaya, Bolivia, 5300 m a.s.l., Pico Espejo, Venezuela, 4750 m a.s.l., Sierra Negra, Mexico, 4650 m a.s.l). WCD at high altitude offer a unique possibility of detecting low gamma fluxes in the 10 GeV - 1 TeV range. The status of the Observatory and data collected from 2007 to date will be presented.
Ultrathin Co/Pt and Co/Pd superlattice films for MgO-based perpendicular magnetic tunnel junctions
Ultrathin [Co/Pt]{sub n} and [Co/Pd]{sub n} superlattice films consisting of 0.14-0.20-nm-thick Co and Pt(Pd) layers were deposited by sputtering. A large perpendicular magnetic anisotropy [(3-9)x10{sup 6} ergs/cm{sup 3}] and an ideal square out-of-plane hysteresis loop were attained even for ultrathin superlattice films with a total thickness of 1.2-2.4 nm. The films were stable against annealing up to 370 deg. C. MgO-based perpendicular magnetic tunnel junctions with this superlattice layer as the free layer showed a relatively high magnetoresistance ratio (62%) and an ultralow resistance-area product (3.9 {Omega} {mu}m{sup 2}) at room temperature. The use of these films will enable the development of gigabit-scale nonvolatile memory.
Yakushiji, K.; Saruya, T.; Kubota, H.; Fukushima, A.; Nagahama, T.; Yuasa, S.; Ando, K. [Spintronics Research Center, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)
Large displacement spherical joint
A new class of spherical joints has a very large accessible full cone angle, a property which is beneficial for a wide range of applications. Despite the large cone angles, these joints move freely without singularities.
Bieg, Lothar F. (Albuquerque, NM); Benavides, Gilbert L. (Albuquerque, NM)
Gas Scavenging of Soluble and Insoluble Organic Vapors by Levitated Water Drops
Three-millimeter-diameter drops of water were levitated with a standing acoustic wave centered in the jet of a small wind tunnel and the volume changes as the drop evaporates in the presence of 1-propanol vapor were measured. The results are ...
Mark Seaver; Amy Barrett
Investigating Water
This 3-ring binder contains teaching plans for 12 lessons on topics such as "Water in Our Daily Lives," "The Water Cycle," "Amazing Aquifers," "Water and Soil," "Aquatic Ecosystems," and "Water Wise Use." Accompanying each lesson plan are activity and record sheets for hands-on learning experiences. This curriculum is intended for students in about 4th to 8th grades.
Howard Jr., Ronald A.
Distribution of Tropical Tropospheric Water Vapor
Utilizing a conceptual model for tropical convection and observational data for water vapor, the maintenance of the vertical distribution of the tropical tropospheric water vapor is discussed. While deep convection induces large-scale subsidence ...
De-Zheng Sun; Richard S. Lindzen
Riming of Graupel: Wind Tunnel Investigations of Collection Kernels and Growth Regimes
Laboratory experiments were carried out in the vertical wind tunnel in Mainz, Germany, to study the collision coalescence growth of single spherical ice particles having initial radii between 290 and 380 ?m while they were freely floated in a ...
Nadine von Blohn; Karoline Diehl; Subir K. Mitra; Stephan Borrmann
Wind Tunnel Tests of Parabolic Trough Solar Collectors: March 2001--August 2003
Conducted extensive wind-tunnel tests on parabolic trough solar collectors to determine practical wind loads applicable to structural design for stress and deformation, and local component design for concentrator reflectors.
Hosoya, N.; Peterka, J. A.; Gee, R. C.; Kearney, D.
Atomic-Scale Chemical Imaging via Combination of Scanning Tunneling and Electron Energy Loss Spectroscopies
Atomic-Scale Chemical Imaging via Combination of Scanning Tunneling and Electron Energy Loss visualization of chemical reaction pathways to provide mechanistic understanding for catalytically important systems at atomic level Develop atomically resolved chemical imaging platform via combination of low
Sponginess and Drop Shedding of Gyrating Hailstones in a Pressure-Controlled Icing Wind Tunnel
Artificial hailstones were grown in an icing wind tunnel under simulated natural conditions, starting from oblate ice spheroids with major and minor diameters of 2.0 and 1.3 cm respectively, while undergoing symmetric gyration. The experiments ...
G. B. Lesins; Roland List
Simulation study of an ultra thin body silicon on insulator tunnel field effect transistor
This paper presents a modified UTB SOI TFET structure and a thorough simulation study of various device design parameters on this structure. Keywords: UTB-SOI-TFET, band-to-band tunneling, sub-threshold swing
Partha Sarathi Gupta; Sayan Kanungo; Hafizur Rahaman; Partha Sarathi Dasgupta
Double Barrier Resonant Tunneling Transistor with a Fully Two Dimensional Emitter
A novel planar resonant tunneling transistor is demonstrated. The growth structure is similar to that of a double-barrier resonant tunneling diode (RTD), except for a fully two-dimensional (2D) emitter formed by a quantum well. Current is fed laterally into the emitter, and the 2D--2D resonant tunneling current is controlled by a surface gate. This unique device structure achieves figures-of-merit, i.e. peak current densities and peak voltages, approaching that of state-of-the-art RTDs. Most importantly, sensitive control of the peak current and voltage is achieved by gating of the emitter quantum well subband energy. This quantum tunneling transistor shows exceptional promise for ultra-high speed and multifunctional operation at room temperature.
Earth pressure balance (EPB) tunneling induced settlements in the Tren Urbano Project, Rio Piedras, Puerto Rico
Underground construction of the Rio Piedras section of the Tren Urbano project involved the construction of twin tunnels (6.3m diameter) with Earth Pressure Balance machines in weathered alluvial soil. The depth of the ...
Abrams, Alejandro J
Analyses of coupled hydrological-mechanical effects during drilling of the FEBEX tunnel at Grimsel
fluid pressure responses observed during TBM drilling of thefluid- pressure responses observed in the rock mass during TBM drillingdrilling, the open boundary at the tunnel wall controls the fluid
Rutqvist, J.; Rejeb, A.; Tijani, M.; Tsang, C.-F.
Fire modeling for Building 221-T - T Plant Canyon Deck and Railroad Tunnel
This report was prepared by Hughes Associates, Inc. to document the results of fire models for building 221-T Canyon Deck and Railroad Tunnel. Backup data is contained in document No. WHC-SD-CP-ANAL-010, Rev. 0.
Oar, D.L.
Investigation of the tunneling emitter bipolar transistor as spin-injector into silicon
In this thesis is discussed the tunneling emitter bipolar transistor as a possible spin-injector into silicon. The transistor has a metallic emitter which as a spin-injector will be a ferromagnet. Spin-polarized electrons ...
Van Veenhuizen, Marc Julien
Our Environment in Hot Water: Comparing Water Heaters, A Life Cycle Approach Comparing Tank and Tankless Water Heaters in California
hot water draw and energy usage for household samples,Support Document [10]. Energy usage for tankless watersuch a large population, energy usage would be reduced and
Lu, Alison
Potential long-term chemical effects of diesel fuel emissions on a mining environment: A preliminary assessment based on data from a deep subsurface tunnel at Rainer Mesa, Nevada test site
The general purpose of the Yucca Mountain Site Characterization Project (YMSCP) Introduced Materials Task is to understand and predict potential long-term modifications of natural water chemistry related to the construction and operation of a radioactive waste repository that may significantly affect performance of the waste packages. The present study focuses on diesel exhaust. Although chemical information on diesel exhaust exists in the literature, it is either not explicit or incomplete, and none of it establishes mechanisms that might be used to predict long-term behavior. In addition, the data regarding microbially mediated chemical reactions are not well correlated with the abiotic chemical data. To obtain some of the required long-term information, we chose a historical analog: the U12n tunnel at Rainier Mesa, Nevada Test Site. This choice was based on the tunnel`s extended (30-year) history of diesel usage, its geological similarity to Yucca Mountain, and its availability. The sample site within the tunnel was chosen based on visual inspection and on information gathered from miners who were present during tunnel operations. The thick layer of dark deposit at that site was assumed to consist primarily of rock powder and diesel exhaust. Surface samples and core samples were collected with an intent to analyze the deposit and to measure potential migration of chemical components into the rock. X-ray diffraction (XRD), x-ray fluorescence (XRF), scanning electron microscopy (SEM) with energy dispersive spectra (EDS) analysis, secondary-ion mass spectrometry (SIMS), and Fourier transform infrared (FTIR) analysis were used to measure both spatial distribution and concentration for the wide variety of chemical components that were expected based on our literature survey.
Meike, A.; Bourcier, W.L.; Alai, M. [and others
Quantum-limited detection of millimeter waves using superconducting tunnel junctions
The quasiparticle tunneling current in a superconductor-insulator- superconductor (SIS) tunnel junction is highly nonlinear. Such a nonlinearity can be used to mix two millimeter wave signals to produce a signal at a much lower intermediate frequency. We have constructed several millimeter and sub-millimeter wave SIS mixers in order to study high frequency response of the quasiparticle tunneling current and the physics of high frequency mixing. We have made the first measurement of the out-of-phase tunneling currents in an SIS tunnel junction. We have developed a method that allows us to determine the parameters of the high frequency embedding circuit by studying the details of the pumped I-V curve. We have constructed a 80--110 GHz waveguide-based mixer test apparatus that allows us to accurately measure the gain and added noise of the SIS mixer under test. Using extremely high quality tunnel junctions, we have measured an added mixer noise of 0.61 {plus_minus} 0.36 quanta, which is within 25 percent of the quantum limit imposed by the Heisenberg uncertainty principle. This measured performance is in excellent agreement with that predicted by Tucker`s theory of quantum mixing. We have also studied quasioptically coupled millimeter- and submillimeter-wave mixers using several types of integrated tuning elements. 83 refs.
Mears, C.A.
The quasiparticle tunneling current in a superconductor-insulator- superconductor (SIS) tunnel junction is highly nonlinear. Such a nonlinearity can be used to mix two millimeter wave signals to produce a signal at a much lower intermediate frequency. We have constructed several millimeter and sub-millimeter wave SIS mixers in order to study high frequency response of the quasiparticle tunneling current and the physics of high frequency mixing. We have made the first measurement of the out-of-phase tunneling currents in an SIS tunnel junction. We have developed a method that allows us to determine the parameters of the high frequency embedding circuit by studying the details of the pumped I-V curve. We have constructed a 80--110 GHz waveguide-based mixer test apparatus that allows us to accurately measure the gain and added noise of the SIS mixer under test. Using extremely high quality tunnel junctions, we have measured an added mixer noise of 0.61 {plus minus} 0.36 quanta, which is within 25 percent of the quantum limit imposed by the Heisenberg uncertainty principle. This measured performance is in excellent agreement with that predicted by Tucker's theory of quantum mixing. We have also studied quasioptically coupled millimeter- and submillimeter-wave mixers using several types of integrated tuning elements. 83 refs.
of ~$3/GJ can be achieved with small-size SWPO gasifiers. · Demonstrate a 5-tpd reduced-scale gasifier at a small municipal POTW. · Construct a 40-tpd commercial biomass gasifier at a large municipal POTW. M-246 into hydrogen  SCW quickly gasifies all organics with minimum char  Water-gas shift contributes significantly
Sensible Heat Observations Reveal Soil-Water Evaporation Dynamics
Soil-water evaporation is important at scales ranging from microbial ecology to large-scale climate. Yet routine measurements are unable to capture rapidly shifting near-surface soil heat and water processes involved in soil-water evaporation. ...
J. L. Heitman; R. Horton; T. J. Sauer; T. M. DeSutter
Cygnus Water Switch Jitter
The Cygnus Dual Beam Radiographic Facility consists of two identical radiographic sources - Cygnus 1 and Cygnus 2. Each source has the following x-ray output: 1-mm diameter spot size, 4 rad at 1 m, 50-ns Full Width Half Max. The diode pulse has the following electrical specifications: 2.25 MV, 60 kA, 60 ns. This Radiographic Facility is located in an underground tunnel test area at the Nevada Test Site (NTS). The sources were developed to produce high-resolution images on subcritical tests which are performed at NTS. Subcritical tests are single-shot, high-value events. For this application, it is desirable to maintain a high level of reproducibility in source output. The major components of the Cygnus machines are: Marx generator, water-filled pulse–forming line (PFL), water-filled coaxial transmission line, three-cell inductive voltage adder, and rod-pinch diode. A primary source of fluctuation in Cygnus shot-to-shot performance is jitter in breakdown of the main PFL switch, which is a "self-break" switch. The PFL switch breakdown time determines the peak PFL charging voltage, which ultimately affects the diode pulse. Therefore, PFL switch jitter contributes to shot-to-shot variation in source endpoint energy and dose. In this paper we will present PFL switch jitter analysis for both Cygnus machines and give the correlation with diode performance. For this analysis the PFL switch on each machine was maintained at a single gap setting which has been used for the majority of shots at NTS. In addition to this analysis, PFL switch performance for different switch gap settings taken recently will be examined. Lastly, implications of source jitter for radiographic diagnosis of subcritical shots will be discussed.
Charles V. Mitton, George D. Corrow, Mark D. Hansen, David J. Henderson, et al.
Large Energy Users Program | Department of Energy
Large Energy Users Program Large Energy Users Program Large Energy Users Program < Back Eligibility Commercial Fed. Government Industrial Institutional Local Government Nonprofit Schools State Government Savings Category Heating & Cooling Commercial Heating & Cooling Heating Cooling Home Weatherization Construction Commercial Weatherization Design & Remodeling Manufacturing Other Appliances & Electronics Heat Pumps Commercial Lighting Lighting Water Heating Maximum Rebate Prescriptive: Varies by equipment type Custom: $200,000 or 30% per project Total Prescriptive and Custom combined: $400,000 per calendar year Program Info Funding Source Focus On Energy Start Date 04/01/2012 Expiration Date 12/31/2013 State Wisconsin Program Type State Rebate Program Rebate Amount Prescriptive: Varies by equipment type
Energy Basics: Water Heating
Storage Water Heaters Tankless Demand Water Heaters Heat Pump Water Heaters Solar Water Heaters Tankless Coil & Indirect Water Heaters Water Heating A variety of...
Conductance fluctuations in chaotic systems with tunnel barriers
Quantum effects are expected to disappear in the short-wavelength, semiclassical limit. As a matter of fact, recent investigations of transport through quantum chaotic systems have demonstrated the exponential suppression of the weak localization corrections to the conductance and of the Fano factor for shot-noise when the Ehrenfest time exceeds the electronic dwell time. On the other hand, conductance fluctuations, an effect of quantum coherence, retain their universal value in the limit of the ratio of Ehrenfest time over dwell time to infinity, when the system is ideally coupled to external leads. Motivated by this intriguing result we investigate conductance fluctuations through quantum chaotic cavities coupled to external leads via (tunnel) barriers of arbitrary transparency. Using the trajectory-based semiclassical theory of transport, we find a linear Ehrenfest time-dependence of the conductance variance showing a nonmonotonous, sinusoidal behavior as a function of the transperancy. Most notably, we find an increase of the conductance fluctuations with the Ehrenfest time, above their universal value, for the transparency less than 0.5. These results, confirmed by numerical simulations, show that, contrarily to the common wisdom, effects of quantum coherence may increase in the semiclassical limit, under special circumstances.
Daniel Waltner; Jack Kuipers; Philippe Jacquod; Klaus Richter
Ultra-low voltage resonant tunnelling diode electroabsorption modulator
Embedding a double barrier resonant tunnelling diode (RTD) in an unipolar InGaAlAs optical waveguide gives rise to a very low driving voltage electroabsorption modulator (EAM) at optical wavelengths around 1550 nm. The presence of the RTD within the waveguide core introduces high non-linearity and negative differential resistance in the current-voltage (I-V) characteristic of the waveguide. This makes the electric field distribution across the waveguide core strongly dependent on the bias voltage: when the current decreases from the peak to the valley there is an increase of the electric field across the depleted core. The electric field enhancement in the core-depleted layer causes the Franz-Keldysh absorption band-edge to red shift, which is responsible for the electroabsorption effect. High frequency ac signals as low as 100 mV can induce electric field high speed switching, producing substantial light modulation (up to 15 dB) at photon energies slightly lower than the waveguide core band-gap energy. The k...
Figueiredo, J M L; Stanley, C R
Ground Water
Water Nature Bulletin No. 408-A February 27, 1971 Forest Preserve District of Cook County George W. Dunne, President Roland F. Eisenbeis, Supt. of Conservation GROUND WATER We take...
Water Dogs
NA Question: I'd like to know about the water dogs and their life cycle? Replies: Water dog, or mud puppy, is a common name for a type of salamander that never develops lungs, but...
Meet with Large Businesses
Meet with Large Businesses Meet with Large Businesses and learn about upcoming acquisitions! * Federal Energy Management Program (FEMP) * National Renewable Energy Laboratory (NREL) * Small Business Administration (SBA) * U.S. Department of Energy / Energy, Efficiency, and Renewable Energy (EERE) * U.S. Department of Energy / Golden Field Office (GFO) * Western Area Power Administration (WAPA) * Colorado Procurement Technical Assistance Center (PTAC)
Water Prism, Volume 2: Prototype Applications
Water Prism is a decision support system (DSS) that evaluates alternative management plans to obtain water resource sustainability at the regional, watershed, or local levels. It considers surface, ground, and impoundment waters and all water-using sectors (industrial, agricultural, municipal, electric power, and the environment). This technical update illustrates how Water Prism is used by applying it to two large watersheds: the Muskingum River Basin (Ohio) and the Green River Basin ...
Investigation of an Asymmetric B Factory in the PEP Tunnel
for the lower voltage requirement. The general caveatrequirement for large-angle crab cavities, with their unwanted impedances and their possibly difficult voltage
Chattapadhyay, A.
Some investigations on the enhancement of boiling heat transfer from planer surface embedded with continuous open tunnels
Boiling heat transfer from a flat surface can be enhanced if continuous open tunnel type structures are embedded in it. Further, improvement of boiling heat transfer from such surfaces has been tried by two separate avenues. At first, inclined tunnels are embedded over the solid surface and an effort is made to optimize the tunnel inclination for boiling heat transfer. Surfaces are manufactured in house with four different inclinations of the tunnels with or without a reentrant circular pocket at the end of the tunnel. Experiments conducted in the nucleate boiling regime showed that 45 deg inclination of the tunnels for both with and without base geometry provides the highest heat transfer coefficient. Next, active fluid rotation was imposed to enhance the heat transfer from tunnel type surfaces with and without the base geometry. Rotational speed imparted by mechanical stirrer was varied over a wide range. It was observed that fluid rotation enhances the heat transfer coefficient only up to a certain value of stirrer speed. Rotational speed values, beyond this limit, reduce the boiling heat transfer severely. A comparison shows that embedding continuous tunnel turns out to be a better option for the increase of heat transfer coefficient compared to the imposition of fluid rotation. But the behavior of inclined tunnels under the action of fluid rotation is yet to be established and can be treated as a future scope of the work. (author)
Das, A.K.; Das, P.K.; Saha, P. [Department of Mechanical Engineering, Indian Institute of Technology, Kharagpur 721 302 (India)
Relationships between Total Water, Condensed Water, and Cloud Fraction in Stratiform Clouds Examined Using Aircraft Data
Relationships among total water, condensed water, and cloud fraction in boundary layer and cold tropospheric stratiform clouds are investigated using a large observational dataset collected by the U.K. Met. Office C-130 aircraft. Values of the ...
Robert Wood; Paul R. Field
Although tidally locked habitable planets orbiting nearby M-dwarf stars are among the best astronomical targets to search for extrasolar life, they may also be deficient in volatiles and water. Climate models for this class of planets show atmospheric transport of water from the dayside to the nightside, where it is precipitated as snow and trapped as ice. Since ice only slowly flows back to the dayside upon accumulation, the resulting hydrological cycle can trap a large amount of water in the form of nightside ice. Using ice sheet dynamical and thermodynamical constraints, I illustrate how planets with less than about a quarter the Earth's oceans could trap most of their surface water on the nightside. This would leave their dayside, where habitable conditions are met, potentially dry. The amount and distribution of residual liquid water on the dayside depend on a variety of geophysical factors, including the efficiency of rock weathering at regulating atmospheric CO{sub 2} as dayside ocean basins dry up. Water-trapped worlds with dry daysides may offer similar advantages as land planets for habitability, by contrast with worlds where more abundant water freely flows around the globe.
Menou, Kristen [Department of Astronomy, Columbia University, 550 West 120th Street, New York, NY 10027 (United States)
EXTENSION WATER SUMMIT PRIORITY: WATER CONSERVATION Leadership Team Subcommittee: Joan Bradshaw Michael Dukes Pierce Jones Kati Migliaccio #12;Water Conservation - Situation · Florida water supplies;Water Conservation Initiative 2: Enhancing and protecting water quality, quantity, and supply Priority 1
Slatton, Clint
Cryogenic studies for the proposed CERN large hadron electron collider (LHEC)
The LHeC (Large Hadron electron Collider) is a proposed future colliding beam facility for lepton-nucleon scattering particle physics at CERN. A new 60 GeV electron accelerator will be added to the existing 27 km circumference 7 TeV LHC for collisions of electrons with protons and heavy ions. Two basic design options are being pursued. The first is a circular accelerator housed in the existing LHC tunnel which is referred to as the "Ring-Ring" version. Low field normal conducting magnets guide the particle beam while superconducting (SC) RF cavities cooled to 2 K are installed at two opposite locations at the LHC tunnel to accelerate the beams. For this version in addition a 10 GeV re-circulating SC injector will be installed. In total four refrigerators with cooling capacities between 1.2 kW and 3 kW @ 4.5 K are needed. The second option
Final Report on LDRD Project: Development of Quantum Tunneling Transistors for Practical Circuit Applications
The goal of this LDRD was to engineer further improvements in a novel electron tunneling device, the double electron layer tunneling transistor (DELTT). The DELTT is a three terminal quantum device, which does not require lateral depletion or lateral confinement, but rather is entirely planar in configuration. The DELTT's operation is based on 2D-2D tunneling between two parallel 2D electron layers in a semiconductor double quantum well heterostructure. The only critical dimensions reside in the growth direction, thus taking full advantage of the single atomic layer resolution of existing semiconductor growth techniques such as molecular beam epitaxy. Despite these advances, the original DELTT design suffered from a number of performance short comings that would need to be overcome for practical applications. These included (i)a peak voltage too low ({approx}20 mV) to interface with conventional electronics and to be robust against environmental noise, (ii) a low peak current density, (iii) a relatively weak dependence of the peak voltage on applied gate voltage, and (iv) an operating temperature that, while fairly high, remained below room temperature. In this LDRD we designed and demonstrated an advanced resonant tunneling transistor that incorporates structural elements both of the DELTT and of conventional double barrier resonant tunneling diodes (RTDs). Specifically, the device is similar to the DELTT in that it is based on 2D-2D tunneling and is controlled by a surface gate, yet is also similar to the RTD in that it has a double barrier structure and a third collector region. Indeed, the device may be thought of either as an RTD with a gate-controlled, fully 2D emitter, or alternatively, as a ''3-layer DELTT,'' the name we have chosen for the device. This new resonant tunneling transistor retains the original DELTT advantages of a planar geometry and sharp 2D-2D tunneling characteristics, yet also overcomes the performance shortcomings of the original DELTT design. In particular, it exhibits the high peak voltages and current densities associated with conventional RTDs, allows sensitive control of the peak voltage by the control gate, and operates nearly at room temperature. Finally, we note under this LDRD we also investigated the use of three layer DELTT structures as long wavelength (Terahertz) detectors using photon-assisted tunneling. We have recently observed a narrowband (resonant) tunable photoresponse in related structures consisting of grating-gated double quantum wells, and report on that work here as well.
Large-Scale Hydropower
Energy.gov (U.S. Department of Energy (DOE))
Large-scale hydropower plants are generally developed to produce electricity for government or electric utility projects. These plants are more than 30 MW in size, and there is more than 80,000 MW...
Solar Power in the Desert: Are the current large-scale solar developments really improving California's environment?
from large-scale solar steam generator systems Persistenceof water as steam power generators. The largest of these
Allen, Michael F.; McHughen, Alan
Large Eddy Simulation of Wind Loads on a Low-Rise ...
... Dynamics (CFD), referred as virtual wind tunnel ... Tunnel Laboratory of the University of Western ... dynamic Smagorinsky-Lilly model does implement a ...
Reusing Water
Reusing Water Reusing Water Reusing Water Millions of gallons of industrial wastewater is recycled at LANL by virtue of a long-term strategy to treat wastewater rather than discharging it into the environment. April 12, 2012 Water from cooling the supercomputer is release to maintain a healthy wetland. Contact Environmental Communication & Public Involvement P.O. Box 1663 MS M996 Los Alamos, NM 87545 (505) 667-0216 Email We reuse the same water up to six times before releasing it back into the environment cleaner than when it was pumped. How many times does LANL reuse water? Wastewater is generated from some of the facilities responsible for the Lab's biggest missions, such as the cooling towers of the Los Alamos Neutron Science Center, one of the Lab's premier science research
Water simulation of sodium reactors
The thermal hydraulic simulation of a large sodium reactor by a scaled water model is examined. The Richardson Number, friction coefficient and the Peclet Number can be closely matched with the water system at full power and the similarity is retained for buoyancy driven flows. The simulation of thermal-hydraulic conditions in a reactor vessel provided by a scaled water experiment is better than that by a scaled sodium test. Results from a correctly scaled water test can be tentatively extrapolated to a full size sodium system.
Grewal, S.S.; Gluekler, E.L.
Recovery of Water from Boiler Flue Gas
RecoveRy of WateR fRom BoileR flue Gas RecoveRy of WateR fRom BoileR flue Gas Background Coal-fired power plants require large volumes of water for efficient operation, primarily for cooling purposes. Public concern over water use is increasing, particularly in water stressed areas of the country. Analyses conducted by the U.S. Department of Energy's National Energy Technology Laboratory predict significant increases in power plant freshwater consumption over the coming years, encouraging the development of technologies to reduce this water loss. Power plant freshwater consumption refers to the quantity of water withdrawn from a water body that is not returned to the source but is lost to evaporation, while water withdrawal refers to the total quantity of water removed from a water source.
Structure of Large-Amplitude Internal Solitary Waves
The horizontal and vertical structure of large-amplitude internal solitary waves propagating in stratified waters on a continental shelf is investigated by analyzing the results of numerical simulations and in situ measurements. Numerical ...
Vasiliy Vlasenko; Peter Brandt; Angelo Rubino
Technoeconomic Evaluation of Large-Scale Electrolytic Hydrogen Production Technologies
Large-scale production of electrolytic hydrogen and oxygen could increase use of baseload and off-peak surplus power. To be competitive, however, water electrolysis will require low-cost electricity.
Water Analysis
- National Energy Technology Laboratory Office of Systems Analyses and Planning EUEC Energy & Environment Conference 2008, EPS,1292008 2 * Water Scarcity Seen Dampening Case...
Wind Tunnel Aeroacoustic Tests of Six Airfoils for Use on Small Wind Turbines: Preprint
Aeroacoustic tests of seven airfoils were performed in an open jet anechoic wind tunnel. Six of the airfoils are candidates for use on small wind turbines operating at low Reynolds number. One airfoil was tested for comparison to benchmark data. Tests were conducted with and without boundary layer tripping. In some cases a turbulence grid was placed upstream in the test section to investigate inflow turbulence noise. An array of 48 microphones was used to locate noise sources and separate airfoil noise from extraneous tunnel noise. Trailing edge noise was dominant for all airfoils in clean tunnel flow. With the boundary layer untripped, several airfoils exhibited pure tones that disappeared after proper tripping was applied. In the presence of inflow turbulence, leading edge noise was dominant for all airfoils.
Migliore, P.; Oerlemans, S.
Intermediate-band photosensitive device with quantum dots having tunneling barrier embedded in organic matrix
A plurality of quantum dots each have a shell. The quantum dots are embedded in an organic matrix. At least the quantum dots and the organic matrix are photoconductive semiconductors. The shell of each quantum dot is arranged as a tunneling barrier to require a charge carrier (an electron or a hole) at a base of the tunneling barrier in the organic matrix to perform quantum mechanical tunneling to reach the respective quantum dot. A first quantum state in each quantum dot is between a lowest unoccupied molecular orbital (LUMO) and a highest occupied molecular orbital (HOMO) of the organic matrix. Wave functions of the first quantum state of the plurality of quantum dots may overlap to form an intermediate band.
Forrest, Stephen R. (Ann Arbor, MI)
Measurement of the Equivalent Thermal Resistance of Rooftop Lawns in a Hot-Climate Wind Tunnel
In a very hot summer equivalent to a Guangzhou summer, the reduction of heat coming into rooms is very important with respect to thermal comfort and energy efficiency. The objective of this study is to investigate the evaporation cooling effect on a rooftop lawn. A hot-climate wind tunnel experiment was carried out in order to obtain and analyze the heat and moisture transport in the rooftop lawn. Furthermore, a calculation with the energy conservation equation was carried out using the results of the hot-climate wind tunnel experiment. The calculated equivalent thermal resistance and synthesis exterior surface heat transfer coefficient were in fairly good agreement with that in the design standard for energy efficiency of residential buildings in the hot summer and warm winter zone, while the average velocity in hot-climate wind tunnel equals the summer average outdoor velocity in Guangzhou.
Meng, Q.; Zhang, Y.; Zhang, L.
Water and Energy
Water in swimming pool Water and Energy The water and energy technology research focuses on improving the efficiency of energy and water use in water delivery, supply and...
about: Conventional Storage Water Heaters Demand (Tankless or Instantaneous) Water Heaters Heat Pump Water Heaters Solar Water Heaters Tankless Coil and Indirect Water Heaters...
Water Resource Impacts of Alternative Fuels
Energy Commission also has produced large number of reports on California's water  energy relationship. NRDC and other NGOs also have produced reports on similar issues #12;8 Modeling Water Resources within per unit (gallon or mmBtu) of ethanol produced NAS (07), Fingerman (08): Net water changes from
California at Davis, University of
Decontamination of large components-test case
The rising per-cubic-foot burial costs, together with the trend toward standardized above-ground burial sites, provides the basis for seeking an alternative to direct burial of large components. Large contaminated components such as steam generators can be safely dismantled and decontaminated for free release, metals recycle, and volume reduction. This grand-scale disposal technology will prove to be an economical and ecological alternative to direct burial or interim storage. Yankee Atomic Electric Company (YAEC) in Bolton, operators and decommissioners of the Yankee Nuclear Power Station in Rowe, Massachusetts, has teamed with Frank W Hake Associates in Memphis, TN, to decontaminate a large component as a test case. The large component is YAEC`s reactor pressure vessel head (RPVH). The 79 100 lb RPVH is surface contaminated with 0.7 Ci (1500 mR/h contact) resulting from 32 yr of operating in a 2000 psi, 530{degrees}F pressurized water reactor environment.
Mancini, A. [Yankee Atomic Electric Co., Bolton, MA (United States); Bosco, B. [Frank W. Hake Associates, Memphis, TN (United States)
e+ e- collider in the VLHC tunnel. Proceedings, Workshop, Chicago, USA, March 9-11, 2001
This document is a collection of the contributions made to the March IIT workshop on an e{sup +}e{sup -} collider in the VLHC tunnel. This machine, which is based on a relatively conservative extrapolation of LEP technology, has a baseline luminosity of 10{sup 33}/cm{sup 2}/s at a CM energy of 370 GeV. The overall parameters and general description of such a machine is described in T. Sen and J. Norem, ''A Very Large Lepton Collider in the VLHC Tunnel'', to be published. A preprint of this paper is included as Appendix 2 of this report. The intention of the workshop was to define the parameters of such a collider and make them available to the community for use in further physics studies. It is clear that the machine cannot compete with a full scale linear collider. Its main interest would be if a VLHC were built and if a linear collider did not already exist. In this case, it could provide a limited and perhaps crucial view of low mass Higgs states. Although the study is incomplete, it does define rather well the parameters of the machine, as well as the challenges that the design faces. The study benefited greatly from the participation of the machine experts that were willing to spend time looking at the design. In this document, the workshop contributions are organized into sections which cover the physics motivation for the machine; the injector; beam dynamics issues in the collider; and accelerator systems. The physics section describes luminosity benchmarks for study of a light Higgs boson, and machine performance issues related to lineshape measurements at the t{bar t} threshold. The contribution on the injector presents a design for a 45 GeV injector. The injection energy is motivated by two considerations: the collider has potential stability problems at injection, which are mitigated by a relatively high injection energy; and, at this energy, the injector can also serve as a Z{sup 0} factory. One of the principal conclusions of the IIT workshop was that this was the most natural way to provide a high-luminosity Z{sup 0} factory with polarized beams. The beam dynamics contributions cover a range of topics, including experience from LEP, design options for the lattice and IR's that aim at increasing the luminosity to close to 10{sup 34}/cm{sup 2}/s, and considerations on beam stability, rf system distribution, beam separation, and radiative spin polarization of the beams. The magnet, vacuum system, and rf system required for the machine are discussed in the accelerator systems contributions. Finally, in the conclusions section, the leading R&D issues for the machine, as identified at the workshop, are summarized. In an Appendix, some thoughts on beam-beam considerations for a VLLC are provided.
Dugan, D., (ed.); /Cornell U., LEPP; Tollestrup, A., (ed.); /Fermilab
Characteristics of wind power on Savonius rotor using a guide-box tunnel
This study investigates to improve and adjust the output power of Savonius rotor under various wind power and suggests the method of prevention the rotor from strong wind disaster. In this study, as the appropriate device to achieve the purpose of it, a guide-box tunnel is employed. The guide-box tunnel is like a rectangular box as wind passage in which a test rotor is included. The area ratio between the inlet and exit of it is variable to adjust the inlet mass flow rate or input power. At first, the experiment was conducted to find the adequate configuration which would provide the best relative performance. The present experiment, however, does not include the test to retain the guide-box tunnel from the strong wind. The experiments include the static torque test of the fixed rotor at any phase angle and the dynamic torque test at rotation of them. Consequently, it was found that the maximum rotor rotational speed was achieved in the range of the guide-box area ratio between 0.3 and 0.7 and the value of the output power coefficient of the rotor with guide-box tunnel of the area ratio 0.43 increases about 1.5 times with three blades and 1.23 times with two blades greater than that without guide-box tunnel, respectively. It seemed that the performance of Savonius rotor within the guide-box tunnel is comparable enough with other methods for augmentation and control of the output. (author)
Irabu, Kunio; Roy, Jitendro Nath [Faculty of Mechanical Engineering, University of the Ryukyus, Senbaru-1, Nishihara, Okinawa 903-0213 (Japan)
Regulation of the intersubunit ammonia tunnel in Mycobacterium tuberculosis glutamine-dependent NAD[superscript +] synthetase
Glutamine-dependent NAD{sup +} synthetase is an essential enzyme and a validated drug target in Mycobacterium tuberculosis (mtuNadE). It catalyses the ATP-dependent formation of NAD{sup +} from NaAD{sup +} (nicotinic acid-adenine dinucleotide) at the synthetase active site and glutamine hydrolysis at the glutaminase active site. An ammonia tunnel 40 {angstrom} (1 {angstrom} = 0.1 nm) long allows transfer of ammonia from one active site to the other. The enzyme displays stringent kinetic synergism; however, its regulatory mechanism is unclear. In the present paper, we report the structures of the inactive glutaminase C176A variant in an apo form and in three synthetase-ligand complexes with substrates (NaAD{sup +}/ATP), substrate analogue {l_brace}NaAD{sup +}/AMP-CPP (adenosine 5'-[{alpha},{beta}-methylene]triphosphate){r_brace} and intermediate analogues (NaAD{sup +}/AMP/PPi), as well as the structure of wild-type mtuNadE in a product complex (NAD{sup +}/AMP/PPi/glutamate). This series of structures provides snapshots of the ammonia tunnel during the catalytic cycle supported also by kinetics and mutagenesis studies. Three major constriction sites are observed in the tunnel: (i) at the entrance near the glutaminase active site; (ii) in the middle of the tunnel; and (iii) at the end near the synthetase active site. Variation in the number and radius of the tunnel constrictions is apparent in the crystal structures and is related to ligand binding at the synthetase domain. These results provide new insight into the regulation of ammonia transport in the intermolecular tunnel of mtuNadE.
Chuenchor, Watchalee; Doukov, Tzanko I.; Resto, Melissa; Chang, Andrew; Gerratana, Barbara (SSRL); (Maryland)
Effects of diesel exhaust on the microbiota within a tuffaceous tunnel system
The abundance and distribution of microbiota that may be impacted by diesel and diesel exhaust were investigated from three depths into the walls and invert (floor) of U12n tunnel at Rainier Mesa, Nevada Test Site, a potential geological analog of Yucca Mountain. Enumerations included total cell counts, and numbers of aerobic heterotrophic, sulfate-reducing, nitrate-reducing, and diesel-degrading bacteria. Additionally, the disappearance of total petroleum hydrocarbons was determined in microcosms containing subsurface materials that were amended with diesel fuel. Results revealed that microbes capable of utilizing diesel and diesel combustion products were present in the subsurface in both the walls and the invert of the tunnel. The abundance of specific bacterial types in the tunnel invert, a perturbed environment, was greater than that observed in the tunnel wall. Few trends of microbial distribution either into the tunnel wall or the invert were noted with the exception of aerobic heterotrophic abundance which increased with depth into the wall and decreased with depth into the invert. No correlation between microbiota and a specific introduced chemical species have yet been determined. The potential for microbial contamination of the tunnel wall during sampling was determined to be negligible by the use of fluorescently labeled latex spheres (1{mu}m in dia.) as tracers. Results indicate that additional investigations might be needed to examine the microbiota and their possible impacts on the geology and geochemistry of the subsurface, both indigenous microbiota and those microorganisms that will likely be introduced by anthropogenic activity associated with the construction of a high-level waste repository.
Haldeman, D.L.; Lagadinos, T.; Amy, P.S. [Univ. of Nevada, Las Vegas, NV (United States); Hersman, L. [Los Alamos National Lab., NM (United States); Meike, A. [Lawrence Livermore National Lab., Livermore, CA (United States)
Estimation of gate-to-channel tunneling current in ultra-thin oxide sub-50nm double gate devices
Double gate (DG) FETs have emerged as the most promising technology for sub-50nm transistor design. However, analysis and control of the gate tunneling leakage in DGFET is necessary to fully exploit their advantages. In this paper we have modeled (numerically ... Keywords: Direct tunneling, Double gate, Leakage, Quantum confinement
Saibal Mukhopadhyay; Keunwoo Kim; Jae-Joon Kim; Shih-Hsien Lo; Rajiv V. Joshi; Ching-Te Chuang; Kaushik Roy
Using tevatron magnets for HE-LHC or new ring in LHC tunnel
Two injector accelerator options for HE-LHC of p{sup +} - p{sup +} collisions at 33 TeV cms energy are briefly outlined. One option is based on the Super-SPS (S-SPS) accelerator in the SPS tunnel, and the other one is based on the LER (Low-Energy-Ring) accelerator in the LHC tunnel. Expectations of performance of the main arc accelerator magnets considered for the construction of the S-SPS and of the LER accelerators are used to tentatively devise some selected properties of these accelerators as potential injectors to HE-LHC.
Piekarz, Henryk; /Fermilab
Attachments for fire modeling for Building 221-T, T Plant canyon deck and railroad tunnel
The purpose of this attachment is to provide historical information and documentation for Document No. WHC-SD-CP-ANAL-008 Rev 0, ``Fire Modeling for Building 221-T--T Plant Canyon Deck and Railroad Tunnel``, dated September 29, 1994. This data compilation contains the following: Resumes of the Technical Director, Senior Engineer and Junior Engineer; Review and Comment Record; Software Files; CFAST Input and Output Files; Calculation Control Sheets; and Estimating Sprinkler Actuation Time in the Canyon and Railroad Tunnel. The T Plant was originally a fuel reprocessing facility. It was modified later to decontaminate and repair PuRex process equipment.
Oar, D.L. [Westinghouse Hanford Co., Richland, WA (United States)
Bose-Hubbard dimer scattered from a potential barrier: from co-tunneling to dissociation
We consider a Bose-Hubbard dimer scattered from a potential barrier. A numerical approach has been developed to treat the stationary scattering problem. It allows to compute the tunneling and dissociation probabilities for arbitrary shape of the potential barrier and arbitrary kinetic energy of the dimer. The obtained results are shown to be in agreement with previous studies of the dimer wave-packet dynamics [A.R.Kolovsky, J.Link, and S.Wimberger, New J. of Phys. {\\bf 14}, 075002 (2012)]. In particular, we reproduce the effect of resonant tunneling found in the cited paper and show that this effect can be enhanced by decreasing the dimer kinetic energy.
Dmitrii N. Maksimov; Andrey R. Kolovsky
Thin-film metal coated insulation barrier in a Josephson tunnel junction. [Patent application
A highly stable, durable, and reproducible Josephson tunnel junction consists of a thin-film electrode of a hard superconductor, a thin oxide insulation layer over the electrode constituting a Josephson tunnel junction barrier, a thin-film layer of stabilizing metal over the barrier, and a second thin-film hard superconductive electrode over the stabilizing film. The thin stabilizing metal film is made only thick enough to limit penetration of the electrode material through the insulation layer so as to prevent a superconductive short.
Hawkins, G.A.; Clarke, J.
Monolithic interconnected module with a tunnel junction for enhanced electrical and optical performance
An improved thermophotovoltaic (TPV) n/p/n device is provided. Monolithic Interconnected Modules (MIMS), semiconductor devices converting infrared radiation to electricity, have been developed with improved electrical and optical performance. The structure is an n-type emitter on a p-type base with an n-type lateral conduction layer. The incorporation of a tunnel junction and the reduction in the amount of p-type material used results in negligible parasitic absorption, decreased series resistance, increased voltage and increased active area. The novel use of a tunnel junction results in the potential for a TPV device with efficiency greater than 24%.
Murray, Christopher S. (Bethel Park, PA); Wilt, David M. (Bay Village, OH)
A Monolithic Interconnected module with a tunnel Junction for Enhanced Electrical and Optical Performance
An improved thermophotovoltaic (TPV) n/p/n device is provided. Monolithic Interconnected Modules (MIMs), semiconductor devices converting infrared radiation to electricity, have been developed with improved electrical and optical performance. The structure is an n-type emitter on a p-type base with an n-type lateral conduction layer. The incorporation of a tunnel junction and the reduction in the amount of p-type material used results in negligible parasitic absorption, decreased series resistance, increased voltage and increased active area. The novel use of a tunnel junction results in the potential for a TPV device with efficiency greater than 24%.
Murray, Christopher Sean; Wilt, David Morgan
Large-Scale Hydropower Basics | Department of Energy
Large-Scale Hydropower Basics Large-Scale Hydropower Basics Large-Scale Hydropower Basics August 14, 2013 - 3:11pm Addthis Large-scale hydropower plants are generally developed to produce electricity for government or electric utility projects. These plants are more than 30 megawatts (MW) in size, and there is more than 80,000 MW of installed generation capacity in the United States today. Most large-scale hydropower projects use a dam and a reservoir to retain water from a river. When the stored water is released, it passes through and rotates turbines, which spin generators to produce electricity. Water stored in a reservoir can be accessed quickly for use during times when the demand for electricity is high. Dammed hydropower projects can also be built as power storage facilities.
Effects of boron composition on tunneling magnetoresistance ratio and microstructure of CoFeB/MgO/CoFeB pseudo-spin-valve magnetic tunnel junctions
The effect of B concentration on the tunneling magnetoresistance (TMR) of (Co{sub 25}Fe{sub 75}){sub 100-x}B{sub x}/MgO/(Co{sub 25}Fe{sub 75}){sub 100-x}B{sub x} (x = 22 and 33) pseudo-spin-valve (P-SV) magnetic tunnel junctions (MTJs) was investigated. The TMR ratios for optimally annealed MTJs with x = 22 and 33 were 340% and 170%, respectively, at room temperature. High resolution transmission electron microscopy (HRTEM) observation showed a weaker (001) texture in the MgO barrier in the MTJ with x = 33. The bottom electrode was not fully crystallized even with a considerable amount of B in the (Co{sub 25}Fe{sub 75}){sub 67}B{sub 33}, while good epitaxy was observed between (001) textured MgO and (Co{sub 25}Fe{sub 75}){sub 78}B{sub 22} electrodes.
Kodzuka, M. [Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-0047 (Japan); Ohkubo, T. [National Institute for Materials Science, Tsukuba 305-0047 (Japan); Hono, K. [Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-0047 (Japan); National Institute for Materials Science, Tsukuba 305-0047 (Japan); Ikeda, S.; Ohno, H. [Center for Spintronics Integrated Systems, Tohoku University, Sendai 980-8577 (Japan); Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577 (Japan); Gan, H. D. [Center for Spintronics Integrated Systems, Tohoku University, Sendai 980-8577 (Japan)
Giant tunneling magnetoresistance up to 330% at room temperature in sputter deposited Co{sub 2}FeAl/MgO/CoFe magnetic tunnel junctions
Magnetoresistance ratio up to 330% at room temperature (700% at 10 K) has been obtained in a spin-valve-type magnetic tunnel junction (MTJ) consisting of a full-Heusler alloy Co{sub 2}FeAl electrode and a MgO tunnel barrier fabricated on a single crystal MgO (001) substrate by sputtering method. The output voltage of the MTJ at one-half of the zero-bias value was found to be as high as 425 mV, which is the largest reported to date in MTJs using Heusler alloy electrodes. The present finding suggests that Co{sub 2}FeAl may be one of the most promising candidates for future spintronics devices applications.
Wang Wenhong; Sukegawa, Hiroaki; Shan, Rong; Mitani, Seiji; Inomata, Koichiro [Magnetic Materials Center, National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba 305-0047 (Japan)
Understanding Tunneling Magnetoresistance During Thermal Annealing in MgO-based Junctions with CoFeB Electrodes
The competition between the interface crystallization and diffusion processes, their influence on the onset of symmetry-filtering coherent tunneling of {Delta}{sub 1} band electrons in the MgO-based magnetic tunnel junctions is investigated. Systematic study of the transport and magnetoresistance during thermal annealing of these junctions shows a unique behavior of the tunneling conductance in the parallel state. The optimal annealing time for achieving giant tunneling magnetoresistance at different temperatures is determined. The evolution of magnetoresistance consists of three distinct regions, responsible by different contributions from CoFeB electrodes and the MgO barrier. The whole phenomenon can be understood through an empirical model based on the Landauer tunneling picture.
Wang, W.; Ni, C; Miao, X; Weiland, C; Shah, L; Fan, X; Parson, P; Jordan-Sweet, J; Kou, X; Zhang, Y
Wind tunnel simulation of wind effects and associated displacement hazards on flat surface construction materials such as plywood
Accidents and hazards continue to plague the construction industry. One often overlooked hazard to workers is the potential for flying debris and materials during high winds. This research was designed to evaluate the wind velocity required to create such an airborne hazard with flat surface materials such as plywood. This research was developed to show select correlations between the wind velocity, lifting forces and the susceptibility to movement of large surface area flat sheets of construction material, specifically four feet by eight feet sheets of floordeck plywood weighing 107 pounds. It also examined and evaluated the correlation of a shape coefficient to movement of materials and wind velocities, so that calculations can be made to adequately predict the potential movement of these materials. This will allow construction supervisors to reasonably prepare for such anticipated conditions. The Texas A&M University low speed wind tunnel was used to place a ftffl-scale stack of plywood floor decking material with the air stream flowing over the stack until top sheet separated or lifted from the stack. Next, a half-scale model was placed in the test section of the tunnel with pressure ports attached to a high speed sampling transducer to measure the actual pressures at select velocities. This allowed for a correlation between the ftifl-scale data and the sampled data. Tests were performed for several front and side angles of the wind striking the edge surface of the materials. Velocities were used up to 60 miles per hour full-scale equivalent. The full-scale model achieved lift forces exceeding the material weight of 107 pounds at one orientation angle at a velocity just below 30 miles per hour. This was consistent with the half-scale test pressures for a similar orientation. Various orientations yielded different forces as was anticipated. From this information a pressure coefficient was developed which when applied with a safety factor allows for reasonable calculations to be made to determine potential hazards and adequately secure materials on any sites where large flat materials may be handled or stored.
Madeley, Jack T.
Large Occlusion Stereo
A method for solving the stereo matching problem in the presence of large occlusion is presented. A data structure—the disparity space image—is defined to facilitate the description of the effects of occlusion on the stereo matching process ... Keywords: disparity-space, dynamic-programming stereo, occlusion, stereo
Aaron F. Bobick; Stephen S. Intille
Composting Large Animal Carcasses
Disposing of large animal carcasses can be a problem for agricultural producers. Composting is a simple, low-cost method that yields a useful product that can be used as fertilizer. In this publication you'll learn the basics of composting, how to build and maintain a compost pile, tools you will need, and how to use the finished compost.
Auvermann, Brent W.; Mukhtar, Saqib; Heflin, Kevin
Electron tunneling in MIS capacitors with the MBE-grown fluoride layers on Si(111) and Ge(111): Role of transverse momentum conservation
The current-voltage characteristics of the metal-insulator-semiconductor tunneling structures with calcium fluoride are simulated using different theoretical models. The results are compared to the data of current measurements on the fabricated capacitors ... Keywords: Calcium fluoride, MIS capacitors, Transverse momentum conservation, Tunnel emitter phototransistor, Tunneling current
Y. Y. Illarionov; M. I. Vexler; S. M. Suturin; V. V. Fedorov; N. S. Sokolov; K. Tsutsui; K. Takahashi
Large Scale Weather Control Using Nuclear Reactors
It is pointed out that controlled release of thermal energy from fission type nuclear reactors can be used to alter weather patterns over significantly large geographical regions. (1) Nuclear heat creates a low pressure region, which can be used to draw moist air from oceans, onto deserts. (2) Creation of low pressure zones over oceans using Nuclear heat can lead to Controlled Cyclone Creation (CCC).(3) Nuclear heat can also be used to melt glaciers and control water flow in rivers.
Moninder Singh Modgil
Definition: Water Cooling | Open Energy Information
Water Cooling Water Cooling Water cooling is commonly defined as a method of using water as a heat conduction to remove heat from an object, machine, or other substance by passing cold water over or through it. In energy generation, water cooling is typically used to cool steam back into water so it can be used again in the generation process.[1] View on Wikipedia Wikipedia Definition Water cooling is a method of heat removal from components and industrial equipment. As opposed to air cooling, water is used as the heat conductor. Water cooling is commonly used for cooling automobile internal combustion engines and large industrial facilities such as steam electric power plants, hydroelectric generators, petroleum refineries and chemical plants. Other uses include cooling the barrels of machine guns, cooling of
Solar Water Heater Basics Solar Water Heater Basics Solar Water Heater Basics August 19, 2013 - 3:01pm Addthis Illustration of an active, closed loop solar water heater. A large, flat panel called a flat plate collector is connected to a tank called a solar storage/backup water heater by two pipes. One of these pipes runs through a cylindrical pump into the bottom of the tank, where it becomes a coil called a double-wall heat exchanger. This coil runs up through the tank and out again to the flat plate collector. Antifreeze fluid runs only through this collector loop. Two pipes run out the top of the water heater tank; one is a cold water supply into the tank, and the other sends hot water to the house. Solar water heaters use the sun's heat to provide hot water for a home or
Scanning tunneling microscopy studies on the structure and stability of model catalysts
An atomic level understanding of the structure and stability of model catalysts is essential for surface science studies in heterogeneous catalysis. Scanning tunneling microscopy (STM) can operate both in UHV and under realistic pressure conditions with a wide temperature span while providing atomic resolution images. Taking advantage of the ability of STM, our research focuses on 1) investigating the structure and stability of supported Au catalysts, especially under CO oxidation conditions, and 2) synthesizing and characterizing a series of alloy model catalysts for future model catalytic studies. In our study, Au clusters supported on TiO2(110) have been used to model supported Au catalysts. Our STM studies in UHV reveal surface structures of TiO2(110) and show undercoordinated Ti cations play a critical role in the nucleation and stabilization of Au clusters on TiO2(110). Exposing the TiO2(110) surface to water vapor causes the formation of surface hydroxyl groups and subsequently alters the growth kinetics of Au clusters on TiO2(110). STM studies on Au/TiO2(110) during CO oxidation demonstrate the real surface of a working catalyst. Au clusters supported on TiO2(110) sinter rapidly during CO oxidation, but are mostly stable in the single component reactant gas, either CO or O2. The sintering kinetics of supported Au clusters has been measured during CO oxidation and gives an activation energy, which supports the mechanism of CO oxidation induced sintering. CO oxidation was also found to accelerate the surface diffusion of Rh(110). Our results show a direct correlation between the reaction rate of CO oxidation and the diffusion rate of surface metal atoms. Synthesis of alloy model catalysts have also been attempted in our study with their structures successfully characterized. Planar Au-Pd alloy films has been prepared on a Rh(100) surface with surface Au and Pd atoms distinguished by STM. The growth of Au-Ag alloy clusters have been studied by in-situ STM on a cluster-to-cluster basis. Moreover, the atomic structure of a solution-prepared Ru3Sn3 cluster has been resolved on an ultra-thin silica film surface. The atomic structure and adsorption sites of the ultrathin silica film have also been well characterized in our study.
Yang, Fan
A Measurement System for Systematic Hydrological Characterization of Unsaturated Fractured Welded Tuff in a Mined Underground Tunnel
A field investigation of unsaturated flow through a lithophysal unit of fractured welded tuff containing lithophysal cavities has been initiated. To characterize flow in this spatially heterogeneous medium, a systematic approach has been developed to perform tests in boreholes drilled at regular intervals in an underground tunnel (drift). In this paper, we describe the test equipment system that has been built for this purpose. Since the field-scale measurements, of liquid flow in the unsaturated, fractured rocks, require continuous testing for periods of days to weeks, the control of test equipment has been fully automated, allowing operation with no human presence at the field site. Preliminary results from the first set of tests are described. These tests give insight into the role of the matrix (perhaps also lithophysal cavities) as potential storage during the initial transient flow prior to the breakthrough of water at the drift crown, as well as the role of connected fractures that provide the subsequent quasi-steady flow. These tests also reveal the impact of evaporation on seepage into the drift.
R. J. Cook; R. Salve; B.M. Freifeld; Y.W. Tsang
Implicit Large Eddy Simulation
National Nuclear Security Administration (NNSA)
Implicit Implicit Large Eddy Simulation (ILES) for High Reynolds Number Flows Len Margolin Applied Physics Division Los Alamos National Laboratory Collaborators: 1. Bill Rider (LANL) 2. Piotr Smolarkiewicz (NCAR) 3. Andrzej Wysogrodski (NCAR) 4. Fernando Grinstein (NRL) firstname.lastname@example.com 1 Implicit Large Eddy Simulation Outline: * What is ILES? * What are its advantages? * Historical perspective * Why does it work? * Some examples firstname.lastname@example.com 2 What is ILES ILES is the direct application of a fluid solver to a high Reynolds number fluid flow with no explicit turbulence model. · The truncation terms of the algorithm serve as an effective model of the effects of the unresolved scales. · Fluid solvers based on Nonoscillatory Finite Volume (NFV) approximations work effectively for ILES. · Fluid solvers based on pseudospectral methods, leapfrog methods, advective form methods, etc. do not work
Density-gradient theory: a macroscopic approach to quantum confinement and tunneling in semiconductor devices
Density-gradient theory provides a macroscopic approach to modeling quantum transport that is particularly well adapted to semiconductor device analysis and engineering. After some introductory observations, the basis of the theory in macroscopic and ... Keywords: Continuum, Density-gradient, Electron transport, Quantum confinement, Quantum tunneling, Semiconductor device simulation, Thermodynamics
M. G. Ancona
Wind Tunnel Experiment for Predicting a Visible Plume Region from a Nuclear Power Plant Cooling Tower
The current paper introduces a wind tunnel experiment to study the effect of the cooling tower of a Nuclear Power Plant (NPP) on the flow and the characteristics of visible plume regions. The relevant characteristics of the flow field near the ...
Guo Dong-peng; Yao Ren-tai; Fan Dan
Mobile Sensor Routing for Parameter Estimation of Distributed Systems Using the Parallel Tunneling Method
The paper deals with the problem of optimal path planning for a sensor network with mutliple mobile nodes, whose measurements are supposed to be primarily used to estimate unknown parameters of a system modelled by a partial differential equation. The ... Keywords: Distributed Parameter Systems, Optimum Experimental Design, Parallel Computing, Sensor Network, Tunneling Algorithm
Tomasz Zi?ba; Dariusz Uci?ski
A Wind Tunnel Investigation on the Riming of Snowflakes. Part II: Natural and Synthetic Aggregates
Natural and artificial snowflakes have been rimed both in free fall and while suspended on a thin flexible fiber in the UCLA cloud tunnel. The results of these experiments show that during the early stage of riming, the motions exhibited by a ...
Tunneling vs. thermionic currents in multi-quantum well photovoltaic structures
Photogeneration in the intrinsic region of a p-i-n device excites carriers in the conduction bands with non-zero currents. A special class of multi-quantum well photovoltaic structures (mqw-PV) is p-i-n PV structures where photo-generation may cause ... Keywords: microelectronics, quantum wells, solar cells, superlattices, tunneling
Argyrios C. Varonides; Robert A. Spalletta
Charged fermion tunnelling from electrically and magnetically charged rotating black hole in de Sitter space
Thermal radiation of electrically charged fermions from rotating black hole with electric and magnetic charges in de Sitter space is considered. The tunnelling probabilities for outgoing and incoming particles are obtained and the Hawking temperature is calculated. The relation for the classical action for the particles in the black hole's background is also found.
M. M. Stetsko
The black-hole area spectrum in the tunneling formalism with GUP
The black hole area spectrum has been studied in the framework of tunneling mechanism, where a Generalized Uncertainty Principle (GUP) has been considered. The results implies in a non evenly spaced spectrum for the black hole area which becomes increasingly spaced as the black hole evaporates.
Silva, C A S
C. A. S. Silva; R. R. Landim
Fast recovery from dual-link or single-node failures in IP networks using tunneling
This paper develops novel mechanisms for recovering from failures in IP networks with proactive backup path calculations and Internet Protocol (IP) tunneling. The primary scheme provides resilience for up to two link failures along a path. The highlight ... Keywords: IP fast reroute, failure recovery, independent trees, multiple-link failure, network protection, node failure
Shrinivasa Kini; Srinivasan Ramasubramanian; Amund Kvalbein; Audun Fosselie Hansen
of a building was explored [2]. Referred to such applications, a VAWT can be so small in physical size that its by the present authors to study the aerodynamic performance of small VAWTs using the experimental and numerical1 WIND-TUNNEL STUDY ON AERODYNAMIC PERFORMANCE OF SMALL VERTICAL-AXIS WIND TURBINES J. J. Miau*1
Leu, Tzong-Shyng "Jeremy"
Unsteady Aerodynamics Experiment Phase VI: Wind Tunnel Test Configurations and Available Data Campaigns
The primary objective of the insteady aerodynamics experiment was to provide information needed to quantify the full-scale, three-dimensional aerodynamic behavior of horizontal-axis wind turbines. This report is intended to familiarize the user with the entire scope of the wind tunnel test and to support the use of the resulting data.
Hand, M. M.; Simms, D. A.; Fingersh, L. J.; Jager, D. W.; Cotrell, J. R.; Schreck, S.; Larwood, S. M.
Investigating the IPv6 teredo tunnelling capability and performance of internet clients
The Teredo auto-tunnelling protocol allows IPv6 hosts behind IPv4 NATs to communicate with other IPv6 hosts. It is enabled by default on Windows Vista and Windows 7. But Windows clients are self-constrained: if their only IPv6 access is Teredo, they ... Keywords: ipv6, teredo
Sebastian Zander; Lachlan L.H. Andrew; Grenville Armitage; Geoff Huston; George Michaelson
Water pollution
Ballast water, which is sea water that is carried in oil tankers to provide stability, can become contaminated with oil. Alyeska Pipeline Service Company runs a water treatment plant at its pipeline terminal at Prot Valdez, Alaska, to treat ballast water before it is discharged into the sea. GAO reviewed EPA's recently reissued National Pollution Discharge Elimination System permit for the Port Valdez facility. In this report, GAO compares the effluent limits and other requirements under the reissued permit with those of the old permit, determines the reasons for changes in the reissued permit, and examines Alyeska's initial efforts to comply with the reissued permit's effluent limits and reporting requirements.
Estimating Large-Scale Precipitation Minus Evapotranspiration from GRACE Satellite Gravity Measurements
Currently, observations of key components of the earth's large-scale water and energy budgets are sparse or even nonexistent. One key component, precipitation minus evapotranspiration (P ? ET), remains largely unmeasured due to the absence of ...
Sean Swenson; John Wahr
National Smart Water Grid
The United States repeatedly experiences floods along the Midwest's large rivers and droughts in the arid Western States that cause traumatic environmental conditions with huge economic impact. With an integrated approach and solution these problems can be alleviated. Tapping into the Mississippi River and its tributaries, the world's third largest fresh water river system, during flood events will mitigate the damage of flooding and provide a new source of fresh water to the Western States. The trend of increased flooding on the Midwest's large rivers is supported by a growing body of scientific literature. The Colorado River Basin and the western states are experiencing a protracted multi-year drought. Fresh water can be pumped via pipelines from areas of overabundance/flood to areas of drought or high demand. Calculations document 10 to 60 million acre-feet (maf) of fresh water per flood event can be captured from the Midwest's Rivers and pumped via pipelines to the Colorado River and introduced upstream of Lake Powell, Utah, to destinations near Denver, Colorado, and used in areas along the pipelines. Water users of the Colorado River include the cities in southern Nevada, southern California, northern Arizona, Colorado, Utah, Indian Tribes, and Mexico. The proposed start and end points, and routes of the pipelines are documented, including information on right-of-ways necessary for state and federal permits. A National Smart Water Grid{trademark} (NSWG) Project will create thousands of new jobs for construction, operation, and maintenance and save billions in drought and flood damage reparations tax dollars. The socio-economic benefits of NWSG include decreased flooding in the Midwest; increased agriculture, and recreation and tourism; improved national security, transportation, and fishery and wildlife habitats; mitigated regional climate change and global warming such as increased carbon capture; decreased salinity in Colorado River water crossing the US-Mexico border; and decreased eutrophication (excessive plant growth and decay) in the Gulf of Mexico to name a few. The National Smart Water Grid{trademark} will pay for itself in a single major flood event.
Beaulieu, R A
Role of Coulomb blockade and spin-flip scattering in tunneling magnetoresistance of FeCo-Si-O nanogranular films
In this work, we report the effect of FeCo atomic fraction (0.33 < x < 0.54) and temperature on the electrical, magnetic, and tunneling magnetoresistance (TMR) properties of FeCo-Si-O granular films prepared by atom beam sputtering technique. Glancing angle x-ray diffraction and TEM studies reveal that films are amorphous in nature. The dipole-dipole interactions (particle-matrix mixing) is evident from zero-field cooled and field-cooled magnetic susceptibility measurements and the presence of oxides (mainly Fe-related) is observed by x-ray photoelectron spectroscopy analysis. The presence of Fe-oxides is responsible for the observed reduction of saturation magnetization and rapid increase in coercivity below 50 K. TMR has been observed in a wide temperature range, and a maximum TMR of -4.25% at 300 K is observed for x = 0.39 at a maximum applied field of 60 kOe. The fast decay of maximum TMR at high temperatures and lower TMR values at 300 K when compared to P{sub FeCo}{sup 2}/(1+P{sub FeCo}{sup 2}), where P{sub FeCo} is the spin polarization of FeCo are in accordance with a theoretical model that includes spin-flip scattering processes. The temperature dependent study of TMR effect reveals a remarkably enhanced TMR at low temperatures. The TMR value varies from -2.1% at 300 K to -14.5% at 5 K for x = 0.54 and a large MR value of -18.5% at 5 K for x = 0.39 is explained on the basis of theoretical models involving Coulomb blockade effects. Qualitatively particle-matrix mixing and the presence of Fe-oxides seems to be the source of spin-flip scattering, responsible for fast decay of TMR at high temperatures. A combination of higher order tunneling (in Coulomb blockade regime) and spin-flip scattering (high temperature regime) explains the temperature dependent TMR of these films.
Kumar, Hardeep; Ghosh, Santanu [Nanostech Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi 110016 (India); Buerger, Danilo; Zhou, Shengqiang; Groetzschel, Rainer; Schmidt, Heidemarie [Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, P.O. Box 510119, 01314 Dresden (Germany); Li, Lin [Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, P.O. Box 510119, 01314 Dresden (Germany); State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100 871 (China); Kabiraj, Debdulal; Avasthi, Devesh Kumar [Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India)
Soil and Vegetation Management: Keys to Water Conservation on Rangeland
The amount of water that soaks into the soil largely determines plant productivity. We can manage and conserve water where and when it falls, and by controlling the kind of vegetation we can make the fullest use of rain water. This publication illustrations the effects of vegetation management on water availability.
Schuster, Joseph L.
Water Boatman
Water Boatman Water Boatman Name: Joshua Location: N/A Country: N/A Date: N/A Question: I am doing a research on water boatman. I go through your web, I only find little information about it. Can you give me its habitat, its appearance, life cycles and communication between themselves and they defenses themselves? Replies: Find a good book in the library on insects, also on pond biology/ecology, as boatmen live in ponds and marshes. It should be easy to find. J.Elliott Try this web site: http://www.dnr.state.il.us/ctap.ctaphome.htm or http://www.dnr.state.il.us/nredu/nredpage.htm this is the state of Illinois Dept. of Natural Resources homepage and somewhere on there is a page called "bugpage". They have pictures and characteristics of aquatic insects there. good luck
gas water heaters; and pressure loss calculations for residentialgas water heaters; and pressure loss calculations for residential
As its name implies, this reactor utilizes an aqueous solution of a fissionable element salt, and is also conventional in that it contains a heat exchanger cooling coil immersed in the fuel. Its novelty lies in the utilization of a cylindrical reactor vessel to provide a critical region having a large and constant interface with a supernatant vapor region, and the use of a hollow sleeve coolant member suspended from the cover assembly in coaxial relation with the reactor vessel. Cool water is circulated inside this hollow coolant member, and a gap between its outer wall and the reactor vessel is used to carry off radiolytic gases for recombination in an external catalyst chamber. The central passage of the coolant member defines a reflux condenser passage into which the externally recombined gases are returned and condensed. The large and constant interface between fuel solution and vapor region prevents the formation of large bubbles and minimizes the amount of fuel salt carried off by water vapor, thus making possible higher flux densities, specific powers and power densities.
King, L.D.P.
Water-Mediated Proton Hopping on an Iron Oxide Surface
The diffusion of hydrogen atoms across solid oxide surfaces is often assumed to be accelerated by the presence of water molecules. Here we present a high-resolution, high-speed scanning tunneling microscopy (STM) study of the diffusion of H atoms on an FeO thin film. STM movies directly reveal a water-mediated hydrogen diffusion mechanism on the oxide surface at temperatures between 100 and 300 kelvin. Density functional theory calculations and isotope-exchange experiments confirm the STM observations, and a proton-transfer mechanism that proceeds via an H3O+-like transition state is revealed. This mechanism differs from that observed previously for rutile TiO2(110), where water dissociation is a key step in proton diffusion.
Merte, L. R.; Peng, Guowen; Bechstein, Ralf; Rieboldt, Felix; Farberow, Carrie A.; Grabow, Lars C.; Kudernatsch, Wilhelmine; Wendt, Stefen; Laegsgaard, E.; Mavrikakis, Manos; Besenbacher, Fleming
Modeling of Plume Downwash and Enhanced Diffusion near Buildings: Comparison to Wind Tunnel Observations for in Arctic Industrial Site
The ability of a modified Industrial Source Complex model to simulate concentration distributions resulting from high wind speeds (neutral conditions) has been evaluated by comparison to data from a wind tunnel study of a Prudhoe Bay, AK oil-...
Alex Guenther; Brian Lamb; Ronald Petersen
Alongwind Dispersion—A Simple Similarity Formula Compared with Observations at 11 Field Sites and in One Wind Tunnel
Observations of alongwind dispersion of clouds were collected from 11 field sites and from one wind tunnel and were used to test simple similarity relations. Because most of the observations consist of concentration time series from fixed ...
Steven R. Hanna; Pasquale Franzese
Nitric Acid Oxidized ZrO$_2$ as the Tunneling Oxide of Cobalt Silicide Nanocrystal Memory Devices
In this study, ZrO$_2$ formed by the nitric acid oxidation method is proposed to be the tunneling oxide for nonvolatile memory device applications. The sputtered Zr thin film was oxidized ...
Chih-Wei Hu; Ting-Chang Chang; Chun-Hao Tu; Yang-Dong Chen; Chao-Cheng Lin; Min-Chen Chen; Jian-Yang Lin; Simon M. Sze; Tseung-Yuen Tseng
Earth pressure balance (EPB) shield tunneling in Bangkok : ground response and prediction of surface settlements using artificial neural networks
Although Earth Pressure Balance (EPB) shields have been used for several decades, very little information exists about the actual mechanisms of shield-ground interaction. The ground response mechanism induced by EPB tunneling ...
Suwansawat, Suchatvee, 1972-
Treatment of Oilfield Produced Water with Dissolved Air Flotation.
??Produced water is one of the major by products of oil and gas exploitation which is produced in large amounts up to 80% of the… (more)
Jaji, Kehinde Temitope
Water and Energy in Mineral Processing
The theme will be "Water and energy in mineral processing". ... Analysis of Polymer Adsorption on Hematite Using Zeta Potential Distributions ... Trends with Selection and Sizing Large Flotation Circuits- What's Available in the Market Place.
A Historical Evaluation of the U12t Tunnel, Nevada Test Site, Nye County, Nevada, Volume 1 of 6
This report presents a historical evaluation of the U12t Tunnel on the Nevada Test Site in southern Nevada. The work was conducted by the Desert Research Institute at the request of the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office and the U.S. Department of Defense, Defense Threat Reduction Agency (DTRA). The U12t Tunnel is one of a series of tunnels used for underground nuclear weapons effects tests on the east side of Rainier and Aqueduct Mesas. Six nuclear weapons effects tests, Mint Leaf, Diamond Sculls, Husky Pup, Midas Myth/Milagro, Mighty Oak, and Mission Ghost, and one high explosive test, SPLAT, were conducted within the U12t Tunnel from 1970 to 1987. All six of the nuclear weapons effects tests and the high explosive test were sponsored by DTRA. Two conventional weapons experiments, Dipole Knight and Divine Eagle, were conducted in the tunnel portal area in 1997 and 1998. These experiments were sponsored by the Defense Special Weapons Agency. The U12t Tunnel complex is composed of the Portal and Mesa Areas and includes an underground tunnel with a main access drift and nine primary drifts, a substantial tailings pile fronting the tunnel portal, a series of discharge ponds downslope of the tailings pile, and two instrumentation trailer parks and 16 drill holes on top of Aqueduct Mesa. A total of 89 cultural features were recorded: 54 at the portal and 35 on the mesa. In the Portal Area, cultural features are mostly concrete pads and building foundations; other features include the portal, rail lines, the camel back, ventilation and cooling system components, communication equipment, and electrical equipment. On the mesa are drill holes, a few concrete pads, a loading ramp, and electrical equipment.
Harold Drollinger; Robert C. Jones; and Thomas F. Bullard; Desert Research Institute, Laurence J. Ashbaugh, Southern Nevada Courier Service and Wayne R. Griffin, Stoller-Navarro Joint Venture
A Historical Evaluation of the U12t Tunnel, Nevada Test Site, Nye County, Nevada, Volume 6 of 6
A Historical Evaluation of the U12t Tunnel, Nevada Test Site, Nye County, Nevada, Volume 3 of 6
A Historical Evaluation of the U12t Tunnel, Nevada Test Site, Nye County, Nevada, Volume 5 of 6
Modeling of Damage, Permeability Changes and Pressure Responses during Excavation of the TSX Tunnel in Granitic Rock at URL, Canada
This paper presents numerical modeling of excavation-induced damage, permeability changes, and fluid-pressure responses during excavation of the TSX tunnel at the underground research laboratory (URL) in Canada. Four different numerical models were applied, using a wide range of approaches to model damage and permeability changes in the excavation disturbed zone (EDZ) around the tunnel. Using in situ calibration of model parameters the modeling could reproduce observed spatial distribution of damage and permeability changes around the tunnel, as a combination of disturbance induced by stress redistribution around the tunnel and by the drill-and-blast operation. The modeling showed that stress-induced permeability increase above the tunnel is a result of micro and macrofracturing under high deviatoric (shear) stress, whereas permeability increases alongside the tunnel as a result of opening of existing microfractures under decreased mean stress. The remaining observed fracturing and permeability changes around the periphery of the tunnel were attributed to damage from the drill-and-blast operation. Moreover, a reasonably good agreement was achieved between simulated and observed excavation-induced pressure responses around the TSX tunnel for 1 year following its excavation. The simulations showed that these pressure responses are caused by poroelastic effects as a result of increasing or decreasing mean stress, with corresponding contraction or expansion of the pore volume. The simulation results for pressure evolution were consistent with previous studies, indicating that the observed pressure responses could be captured in a Biot model using a relatively low Biot-Willis coefficient, {alpha} {approx} 0.2, a porosity of n {approx} 0.007, and a relatively low permeability of k {approx} 2 x 10{sup -22} m{sup 2}, which is consistent with the very tight, unfractured granite at the site.
Rutqvist, Jonny; Borgesson, Lennart; Chijimatsu, Masakazu; Hernelind, Jan; Jing, Lanru; Kobayashi, Akira; Nguyen, Son
A Historical Evaluation of the U12t Tunnel, Nevada Test Site, Nye County, Nevada, Volume 2 of 6
A Historical Evaluation of the U12t Tunnel, Nevada Test Site, Nye County, Nevada, Volume 4 of 6
The Control System for the Cryogenics in the LHC Tunnel
The Large Hadron Collider makes extensive use of superconductors, in magnets for bending and focusing the particles, and in RF cavities for accelerating them, which are operated at 1.9 K and 4.5 K. The process automation for the cryogenic distribution around the accelerator circumference is based on 16 Programmable Logic Controllers, each running 250 control loops, 500 alarms and interlocks, and a phase sequencer. Spread along 27 km and under ionizing radiation, 15 000 cryogenic sensors and actuators are accessed through industrial field networks. We describe the main hardware and software components of the control system, their deployment and commissioning, together with the project organization, challenges faced, and solutions found.
Gomes, P; Antoniotti, F; Avramidou, R; Balle, Ch; Blanco-Vińuela, E; Carminati, Ch; Casas-Cubillos, J; Ciechanowski, M; Dragoneas, A; Dubert, P; Fampris, X; Fluder, C; Fortescue, E; Gaj, W; Gousiou, E; Jeanmonod, N; Jod?owski, P; Karagiannis, F; Klisch, M; López, A; Macuda, P; Malinowski, P; Molina, E; Paiva, S; Patsouli, A; Penacoba, G; Sosin, M; Soubiran, M; Suraci, A; Tovar, A; Vauthier, N; Wolak, T; Zwalinski, L
Spatial Water Balance in Texas
Water availability is critical to the economy in the state of Texas. Numerous reservoirs and conveyance structures have been constructed across the State to meet the water supply needs of farmers, municipalities, industries, and power generating facilities. Despite this extensive water management system, water supply remains a concern because of increasing populations and uncertainties about climate stability. The rainfall map of Texas shown in Figure 1.1 clearly shows that water management is a spatial problem. The State as a whole receives about 711 mm year-1 of rainfall, while the area of the State east of the 100th meridian receives 890 mm year-1 and the area west of the 100th meridian receives only 457 mm year-1. In addition to water supply concerns, the assessment of non-point source pollution is another important issue that is largely dependent on the spatial distribution of runoff. Although, the focus of this report is not to address water supply or pollution issues directly, an improved understanding of the spatial water balance - the partitioning of precipitation between evaporation, runoff, and groundwater recharge at different points in space - will directly benefit those who wish to assess water resource availability and non-point source pollution potential across the State. The goal of this study was to gain an improved understanding of the stocks of water in different components (air, soil, water bodies) of the hydrologic cycle and the fluxes between these components. A basic approach for determining stocks and fluxes involves the calculation of a water balance. A water balance, applied to a particular control volume, is an application of the law of conservation of mass which states that matter cannot be created or destroyed. To achieve a balance, the rate of change of storage of water within the control volume must be equal to the difference between its rates of inflow and outflow across the control surface. In this study, three independent water balance models were constructed to model different components of the hydrologic cycle - an atmospheric water balance, a soil-water balance, and a surface water balance. These models were constructed using a geographic information system (GIS). A GIS provides a framework for storing and manipulating spatial data and facilitates modeling on control volumes of various sizes and shapes. In all three cases, the choice of modeling unit was driven by the resolution and characteristics of the input data. The control volumes for the atmospheric, soil, and surface water balance models respectively are (1) an imaginary column confined horizontally by the boundary of Texas and extending to the 300 mb pressure level, (2) 0.5° cells with a depth equal to the plant-extractable water capacity of the soil, and (3) 166 gaged watersheds of differing sizes and shapes. Neither the atmospheric nor the surface water balance involve any simulation of physical processes and are simply mass balances based on empirical data. The soil-water balance does attempt to simulate evaporation from the soil through the use of a soil-moisture extraction function. Both the atmospheric and soil-water balance models are time-varying models, while the surface water balance model is steady-state and uses an empirical relationship to estimate mean annual runoff and evaporation in ungaged areas. One advantage of making three independent water balance calculations is that checks for consistency can be made among the three models. For example, all three models yield an estimate of actual evapotranspiration which is a difficult quantity to estimate, particularly at the regional scale. Previous studies at the scale of Texas have estimated only evaporation from open water surfaces and potential evapotranspiration from the land surface (TDWR, 1983; Dugas and Ainsworth, 1983).
Reed, Seann; Maidment, David; Patoux, Jerome
Large forging manufacturing process
A process for forging large components of Alloy 718 material so that the components do not exhibit abnormal grain growth includes the steps of: a) providing a billet with an average grain size between ASTM 0 and ASTM 3; b) heating the billet to a temperature of between 1750.degree. F. and 1800.degree. F.; c) upsetting the billet to obtain a component part with a minimum strain of 0.125 in at least selected areas of the part; d) reheating the component part to a temperature between 1750.degree. F. and 1800.degree. F.; e) upsetting the component part to a final configuration such that said selected areas receive no strains between 0.01 and 0.125; f) solution treating the component part at a temperature of between 1725.degree. F. and 1750.degree. F.; and g) aging the component part over predetermined times at different temperatures. A modified process achieves abnormal grain growth in selected areas of a component where desirable.
Thamboo, Samuel V. (Latham, NY); Yang, Ling (Niskayuna, NY)
Spectroscopy and capacitance measurements of tunneling resonances in an Sb-implanted point contact.
We fabricated a split-gate defined point contact in a double gate enhancement mode Si-MOS device, and implanted Sb donor atoms using a self-aligned process. E-beam lithography in combination with a timed implant gives us excellent control over the placement of dopant atoms, and acts as a stepping stone to focused ion beam implantation of single donors. Our approach allows us considerable latitude in experimental design in-situ. We have identified two resonance conditions in the point contact conductance as a function of split gate voltage. Using tunneling spectroscopy, we probed their electronic structure as a function of temperature and magnetic field. We also determine the capacitive coupling between the resonant feature and several gates. Comparison between experimental values and extensive quasi-classical simulations constrain the location and energy of the resonant level. We discuss our results and how they may apply to resonant tunneling through a single donor.
Wendt, Joel Robert; Rahman, Rajib; Ten Eyck, Gregory A.; Eng, Kevin; Carroll, Malcolm S.; Young, Ralph Watson; Lilly, Michael Patrick; Stalford, Harold Lenn; Bishop, Nathaniel; Bielejec, Edward Salvador
Evaluation of barrier uniformity in magnetic tunnel junctions prepared using natural oxidation of thin Mg layers
We fabricated submicron magnetic tunnel junctions (MTJs) using natural oxidation of thin Mg layers deposited by dc sputtering. The MTJs exhibited magnetoresistance (MR) ratios of up to about 150% with a low resistance-area product (R{sub p}A) of 8 {Omega} {mu}m{sup 2}, which are comparable to those for radio-frequency-sputtered MgO barriers. The submicron MTJs had highly variable MR and R{sub p}A values due to a high pinhole density (20 {mu}m{sup -2}) in the barriers, whereas current-in-plane-tunneling (CIPT) measurements on the same MTJ films revealed highly reproducible MR and R{sub p}A values. This indicates that reproducible CIPT measurements do not necessarily give accurate results of MR and R{sub p}A at high pinhole densities.
Seki, Takayuki; Kubota, Hitoshi; Fukushima, Akio; Yakushiji, Kay; Yuasa, Shinji; Ando, Koji [National Institute of Advanced Industrial Science Technology (AIST), Spintronics Research Center, Central 2, Umezono 1-1-1, Tsukuba, Ibaraki 305-8568 (Japan); Maehara, Hiroki; Yamagata, Shinji; Okuyama, Hiroki; Tsunekawa, Koji [Department of Spin Technology Development, Process Development Center, Canon ANELVA Corporation, Kurigi 2-5-1, Asao, Kawasaki, Kanagawa 215-8550 (Japan)
Energy and Effective Mass Dependence of Electron Tunnelling Through Multiple Quantum barriers in Different Heterostructures
Tunneling of electrons through the barriers in heterostructures has been studied, within unified transfer matrix approach. The effect of barrier width on the transmission coefficient of the electrons has been investigated for different pairs of semi conducting materials that are gaining much importance recently. These pairs include CdS/CdSe, AlGaAs/GaAs and InAs/AlSb. Barrier dimensions have been reduced from 20nm to 5nm to observe the effect of scaling on tunneling properties. Material depended is highlighted for electrons with energy varying from below the barrier height to above it. The electron effective mass inside the barrier and the well are often different. The results show that the coupling effect leads to significant changes on the transmission effect. . The effective-mass dependant transmission coefficient has been plotted with respect to electron energy. The computation is based on the transfer matrix method by using MATLAB.
Jatindranath Gain; Madhumita Das Sarkar; Sudakshina Kundu
Atomic-scale properties of semiconductor heterostructures probed by scanning tunneling microscopy
The engineering of advanced semiconductor heterostructure materials and devices requires a detailed understanding of, and control over, the structure and properties of semiconductor materials and devices at the atomic to nanometer scale. Cross-sectional scanning tunneling microscopy has emerged as a unique and powerful method to characterize structural morphology and electronic properties in semiconductor epitaxial layers and device structures at these length scales. The basic experimental techniques in cross-sectional scanning tunneling microscopy are described, and some representative applications to semiconductor heterostructure characterization drawn from recent investigations in the authors laboratory are discussed. Specifically, they describe some recent studies of InP/InAsP and InAsP/InAsSb heterostructures in which nanoscale compositional clustering has been observed and analyzed.
Yu, E.T.; Zuo, S.L.; Bi, W.G.; Tu, C.W. [Univ. of California, San Diego, La Jolla, CA (United States). Dept. of Electrical and Computer Engineering; Biefeld, R.M.; Allerman, A.A. [Sandia National Labs., Albuquerque, NM (United States)
Role of Amorphous Silicon and Tunneling in Heterojunction with Intrinsic Thin Layer (HIT) Solar Cells
This work analyzes heterojunction with intrinsic thin layer (HIT) solar cells using numerical simulations. The differences between the device physics of cells with p- and n-type crystalline silicon (c-Si) wafers are substantial. HIT solar cells with n-type wafers essentially form a n/p/n structure, where tunneling across the junction heterointerfaces is a critical transport mechanism required to attain performance exceeding 20%. For HIT cells with p-type wafers, only tunneling at the back-contact barrier may be important. For p-wafer cells, the hydrogenated amorphous silicon (a-Si:H) between the indium tin oxide (ITO) and crystalline silicon may act as a passivating buffer layer but, otherwise, does not significantly contribute to device performance. For n-wafer cells, the carrier concentration and band alignment of this a-Si:H layer are critical to device performance.
Kanevce, A.; Metzger, W. K.
Measurement and Modeling of Algal Biokinetics in Highly Eutrophic Waters
Page 1 of 20 Introduction Algae are now recognized as aLarge standing crops of algae can support higher trophicproductivity, but large algae blooms can also impair water
Stringfellow, William T.; Borglin, Sharon E.; Hanlon, Jeremy S.
Surface Water Temperatures At Shore Stations, United States West Coast 1980
has a large-volume water intake from which the daily wateroff the rocks near the water intake for the laboratory.Off rocks near water Intake for laboratory Thermograph
Effects of elemental distributions on the behavior of MgO-based magnetic tunnel junctions.
Three-dimensional atom-probe tomography and transmission electron microscopy have been utilized to study the effects of Ta getter presputtering and either a Mg or Ru free-layer cap on the elemental distributions and properties of MgO-based magnetic tunnel junctions after annealing. Annealing the samples resulted in crystallization of the amorphous CoFeB layer and diffusion of the majority of the boron away from the crystallized CoFeB layers. The Ta getter presputter is found to reduce the segregation of boron at the MgO/CoFeB interface after annealing, improving the tunneling magnetoresistance of the tunnel junction. This effect is observed for samples with either a Ru free-layer cap or a Mg free-layer cap and is thought to be a result of a reduced oxygen concentration within the MgO due to the effect of Ta getter presputtering. A Ru free-layer cap provides superior magnetic and magnetotransport properties compared to a Mg free-layer cap. Mg from the Mg free-layer cap is observed to diffuse toward the MgO tunnel barrier upon annealing, degrading both the crystalline quality of the CoFeB and magnetic isolation of the CoFeB free-layer from the CoFeB reference-layer. Lateral variations in the B distribution within the CoFeB free-layer are observed in the samples with a Ru free-layer cap, which are associated with crystalline and amorphous grains. The B-rich, amorphous grains are found to be depleted in Fe, while the B-poor crystalline grains are slightly enriched in Fe.
Schreiber, D. K.; Choi, Y. S.; Liu, Y.; Chiaramonti, A. N.; Seidman, D. N.; Petford-Long, A. K. (Center for Nanoscale Materials); ( MSD); (Northwestern Univ.); (Canon-ANELVA Corp.)
Coherent generation of nonclassical light on a chip via photon-induced tunneling and blockade
We report the observation of nonclassical light generated via photon blockade in a photonic crystal cavity with a strongly coupled quantum dot. By tuning the frequency of the probe laser with respect to the cavity and quantum dot resonance we can probe the system in either photon blockade or photon-induced tunneling regime. The transition from one regime to the other is confirmed by the measurement of the second order correlation that changes from anti-bunching to bunching.
Andrei Faraon; Ilya Fushman; Dirk Englund; Nick Stoltz; Pierre Petroff; Jelena Vuckovic
High resolution seismic imaging of Rainier Mesa using surface reflection and surface to tunnel tomography
In the interpretation of seismic data to infer properties of an explosion source, it is necessary to account for wave propagation effects. In order to understand and remove these propagation effects, it is necessary to have a model. An open question concerning this matter is the detail and accuracy which must be present in the velocity model in order to produce reliable estimates in the estimated source properties. While it would appear that the reliability of the results would be directly related to the accuracy of the velocity and density models used in the interpretation, it may be that certain deficiencies in these models can be compensated by the and amount of seismic data which is used in the inversion. The NPE provided an opportunity to test questions of this sort. In August 1993, two high resolution seismic experiments were performed in N-Tunnel and on the surface of Rainier Mesa above it. The first involved a surface-to-tunnel imaging experiment with sources on the surface and receivers in tunnel U12n.23 about 88 meters west of the NPE. It was possible to estimate the apparent average velocity between the tunnel and the surface. In a separate experiment, a high resolution reflection experiment was performed in order to image the lithology in Rainier Mesa. Good quality, broad band, reflections were obtained from depths extending into the Paleozoic basement. A high velocity layer near the surface is underlain by a thick section of low velocity material, providing a nonuniform but low average velocity between the depth of the NPE and the surface.
Majer, E.L.; Johnson, L.R.; Karageorgi, E.K.; Peterson, J.E.
Property:Velocity(m/s) | Open Energy Information
Velocity(m/s) Velocity(m/s) Jump to: navigation, search Property Name Velocity(m/s) Property Type String Pages using the property "Velocity(m/s)" Showing 21 pages using this property. A Alden Small Flume + >0.9 + B Bucknell Hydraulic Flume + 2.7 + C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + 17 + Carderock 3-ft Variable Pressure Cavitation Water Tunnel + 25.8 + Carderock Circulating Water Channel + 5.2 + Carderock Large Cavitation Tunnel + 18 + Carderock Subsonic Wind Tunnel + 83.8 + D DeFrees Flume 1 + 2 + DeFrees Flume 2 + 2 + DeFrees Flume 3 + 2 + DeFrees Flume 4 + 2 + M MHL Free Surface Channel + 2 + MHL High Speed Cavitation + 25.9 + MHL Student Tunnel + 4.6 + P Penn Large Water Tunnel + 16.8 + Penn Small Water Tunnel + 21 + S SAFL Channel + 6.1 +
Giromill wind tunnel test and analysis. Volume II. Technical discussion. Final report, June 1976--October 1977
A wind tunnel test of a Giromill rotor was conducted. The objective of this test was to substantiate the performance computed by the Larsen cyclogiro vortex theory. Additional objectives were to obtain performance comparison data between the Giromill, a sinusoidal blade modulation Giromill, a Darrieus rotor, and a modified Darrieus rotor that flips the blades a few degrees. A three bladed Giromill rotor having a diameter of 2.13 m (7 ft) and a span of 1.52 m (5 ft) was tested in the McDonnell Aircraft Company 15 x 20 ft Mini Speed Wind Tunnel. The blade modulations were accomplished through use of a cam and push rod arrangement. Replaceable cams provided the desired blade modulation at the various operating points. Various operating conditions were achieved by adjusting the rotor RPM and tunnel speed. The results show that the Giromill has good performance, equal to or much better than that predicted by theory, and outperforms the other types of vertical axis wind turbines tested.
Moran, W.A.
Wind tunnel test of 1/30 scale heliostat field array model. Test report
From 9 January through 20 January 1978, Honeywell conducted a wind tunnel test on a 1/30 scale partial heliostat field. The heliostats were per Honeywell's design developed under the 10 megawatt central receiver pilot electrical power plant subsystem research experiment contract. Likewise, the scaled section of the field geometry duplicated the proposed circular layout. Testing was conducted at the Georgia Institute of Technology's 9 foot subsonic tunnel. The objective of the test was to ascertain from a qualitative standpoint the field effects upon wind loading within a heliostat field. To accomplish this, numerous pressure tap measurements at different heights and at different field positions were taken with varying wind speeds, fence designs, and heliostat gimbal orientations. The Department of Energy specified boundary layer profile was also scaled by 1/30 in order to simulate the total wind effects as accurately as possible taking into account the potentially severe scaling or Reynolds number effects at a 1/30 scale. After initial model set-up within the tunnel and scaled boundary layer generated, 91 separate runs were accomplished. The results do demonstrate the high sensitivity of wind loading upon the collector field due to the actual heliostat orientation and fence geometry. Vertical pressure gradients within the model field and flow reentry angles provide a good qualitative feel as to the full scale environment that might be expected and point to the need for specific additional testing to further explore potentially dangerous conditions.
Brown, G. L.
Definition: Water Wheels | Open Energy Information
Wheels Wheels Jump to: navigation, search Dictionary.png Water Wheels A water wheel is a large wheel that takes energy in free-flowing or falling water and converts it into a useful form of energy.[1] View on Wikipedia Wikipedia Definition A water wheel is a machine for converting the energy of free-flowing or falling water into useful forms of power, often in a watermill. A water wheel consists of a large wooden or metal wheel, with a number of blades or buckets arranged on the outside rim forming the driving surface. Most commonly, the wheel is mounted vertically on a horizontal axle, but the tub or Norse wheel is mounted horizontally on a vertical shaft. Vertical wheels can transmit power either through the axle or via a ring gear and typically drive belts or gears; horizontal wheels usually directly drive their load.
Modeling and optimization of water quality in a large-scale regional water supply system
Resour. Plng. and Mgmt . , ASCE, 121(3), 260-269. Dosso, S.Resour. Plng. and Mgmt . , ASCE, 119(6), Ostfeld, A. , andResour. Plng. and Mgmt. , ASCE, 119(6), Ostfeld, A. , and
Tu, Ming-Yen; Tsai, Frank T-C.; Yeh, William W-G.
Reliable water supply system design under uncertainty
Given the natural variability and uncertainties in long-term predictions, reliability is a critical design factor for water supply systems. However, the large scale of the problem and the correlated nature of the involved uncertainties result in models ... Keywords: Data uncertainty, Robust optimization, Spatially correlated data, Water supply system
G. Chung; K. Lansey; G. Bayraksan
Optimal basis set for ab-initio calculations of energy levels in tunneling structures, using the covariance matrix of the wave functions
The paper proposes a method to obtain the optimal basis set for solving the self consistent field (SCF) equations for large atomic systems in order to calculate the energy barriers in tunneling structures, with higher accuracy and speed. Taking into account the stochastic-like nature of the samples of all the involved wave functions for many body problems, a statistical optimization is made by considering the covariance matrix of these samples. An eigenvalues system is obtained and solved for the optimal basis set and by inspecting the rapidly decreasing eigenvalues one may seriously reduce the necessary number of vectors that insures an imposed precision. This leads to a potentially significant improvement in the speed of the SCF calculations and accuracy, as the statistical properties of a large number of wave functions in an large spatial domain may be considered. The eigenvalue problem has to be solved only few times, so that the amount of time added may be much smaller that the overall iterating SCF calculations. A simple implementation of the method is presented for a situation where the analytical solution is known, and the results are encouraging.
Sever Spanulescu
Bright Water- hydrosols, water conservation and climate change
Since air-water and water-air interfaces are equally refractive, cloud droplets and microbubbles dispersed in bodies of water reflect sunlight in much the same way. The lifetime of sunlight-reflecting microbubbles, and hence the scale on which they may be applied, depends on Stokes Law and the influence of ambient or added surfactants. Small bubbles backscatter light more efficiently than large ones, opening the possibility of using highly dilute micron-radius hydrosols to substantially brighten surface waters. Such microbubbles can noticeably increase water surface reflectivity, even at volume fractions of parts per million and such loadings can be created at an energy cost as low as J m-2 to initiate and milliwatts m-2 to sustain. Increasing water albedo in this way can reduce solar energy absorption by as much as 100 W m-2, potentially reducing equilibrium temperatures of standing water bodies by several Kelvins. While aerosols injected into the stratosphere tend to alter climate globally, hydrosols can be...
Seitz, Russell
CALIFORNIA ENERGY Large HVAC Building
CALIFORNIA ENERGY COMMISSION Large HVAC Building Survey Information Database of Buildings over 100 Design of Large Commercial HVAC Systems research project, one of six research elements in the Integrated Design of Large Commercial HVAC Systems Integrated Design of Small Commercial HVAC Systems Integrated
Hydrogen Production From Metal-Water Reactions
. Current methods of hydrogen storage in automobiles are either too bulky (large storage space for gas phase) or require a high input energy (cooling or pressurization systems for liquid hydrogen), making widespread use abundance, high- energy content, and large surface area, is able to combine with water to produce hydrogen
Barthelat, Francois
Efficient Water Use & Management
Sustainability Goals Water Use Goal 4: Efficient Water Use & Management Aware of the arid climate of northern New Mexico, water reduction and conservation remains a primary...
Water Permits (Louisiana)
The Water Permits Division authorizes permits administered under the Water Quality Regulations. Louisiana's Water Quality Regulations require permits for the discharge of pollutants from any point...
A white paper describing produced water from production ofCE, Veil JA. 2009. Produced Water Volumes and Managementunderground formations (produced water) are often extracted
of California's Water Conservation Standards for ResidentialCalifornia Urban Water Conservation Council, 2006. http://http://www.nrdc.org/water/conservation/edrain/edrain.pdf
Texas Hot Water Report
coil hot water storage tank, a backup instantaneous electric water heater, a hydronic fan coil unit for space heating, and an efficient plumbing manifold for domestic hot water...
Proposal for the award of a contract for dismantling, removal and packaging of the existing Heating, Ventilation and Air-Conditioning (HVAC) systems in the PS tunnel
Evidence of Photocatalytic Dissociation of Water on TiO2 with Atomic Resolution
Photocatalytic water splitting reaction on TiO2 surface is one of the fundamental issues that bears significant implication in hydrogen energy technology and has been extensively studied. However, the existence of the very first reaction step, the direct photo-dissociation of water, has been disregarded. Here, we provide unambiguously experimental evidence to demonstrate that adsorbed water molecules on reduced rutile TiO2(110)-1\\times1 surface can be dissociated under UV irradiation using low temperature scanning tunneling microscopy. It is identified that a water molecule at fivefold coordinated Ti (Ti5c) site can be photocatalytically dissociated, resulting in a hydroxyl at Ti5c and another hydroxyl at bridge oxygen row. Our findings reveal a missing link in the photocatalytic water splitting reaction chain, which greatly contribute to the detailed understanding of underlying mechanism.
Tan, Shijing; Wang, Yang; Zhao, Jin; Zhao, Aidi; Wang, Bing; Luo, Yi; Yang, Jinlong; Hou, J G
Giant tunneling magnetoresistance up to 410% at room temperature in fully epitaxial Co/MgO/Co magnetic tunnel junctions with bcc Co(001) electrodes
Fully epitaxial Co(001)/MgO(001)/Co(001) magnetic tunnel junctions (MTJs) with metastable bcc Co(001) electrodes were fabricated with molecular beam epitaxy. The MTJs exhibited giant magnetoresistance (MR) ratios up to 410% at room temperature, the highest value reported to date. Temperature dependence of the MR ratio was observed to be very small compared with fully epitaxial Fe/MgO/Fe and textured CoFeB/MgO/CoFeB MTJs. The MR ratio of the Co/MgO/Co MTJ showed larger bias voltage dependence than that of the epitaxial Fe/MgO/Fe MTJs, which probably reflects the band structures of bcc Co and Fe for the k{sub parallel}=0 direction.
Yuasa, Shinji; Fukushima, Akio; Kubota, Hitoshi; Suzuki, Yoshishige; Ando, Koji [National Institute of Advanced Industrial Science and Technology (AIST), Nanoelectronics Research Institute, Tsukuba, Ibaraki 305-8568 (Japan) and SORST, Japan Science and Technology Agency (JST), Kawaguchi, Saitama 332-0012 (Japan); National Institute of Advanced Industrial Science and Technology (AIST), Nanoelectronics Research Institute, Tsukuba, Ibaraki 305-8568 (Japan)
Drinking Water Problems: Lead
Lead in drinking water can damage the brain, kidneys, nervous system and red blood cells. This publication explains how lead can enter drinking water, how to have your water tested, and how to eliminate lead from drinking water.
Dozier, Monty; McFarland, Mark L.
Water Conservation Tips
Gardener Water Conservation Tips fo r t h e UCSC Farm &share some of the water-conservation techniques used at theWinter Squash Water Conservation Mulches will save water,
Brown, Martha
Gardener Water Conservation Tips fo r t h e UCSC Farm &we share some of the water-conservation techniques used atWinter Squash Water Conservation Mulches will save water,
Research on Multistep Electricity Price Model with Bidirectional Regulation for Large Consumers
A multistep electricity price model with bidirectional regulation is proposed for large adjustable consumers in the area with abundant hydropower. In order to guide large consumers to regulate electricity consumption manners for resource utilization, ... Keywords: multistep electricity price, bidirectional regulation, large consumers, high and low water period, Monte Carlo simulation, price elasticity of demand
Xia Lei; Dong-xian Yu; Xiao-li Bai
Water watch
The Hydropower Generation Report provides generation figures for the largest hydropower producers in each of six regions in the US. The report compares, for each month, the amount of hydroelectricity generated (in thousands of megawatt-hours) by each producers in the last two years to the ten-year average for that month. This database is used to figure long-term generation averages and percent of averages. The producers regularly provide current generation data to update the database. This issue of [open quotes]Water Watch[close quotes] focuses on winter snow conditions across the US as of mid-January. In addition, the department provides an outlook of spring flood potential. The information presented is based on data from the US Geological Survey, the National Weather Service, and the Soil Conservation Service.
Water Beetles
Beetles Beetles Nature Bulletin No. 639-A April 29, 1961 Forest Preserve District of Cook County George W. Dunne, President Roland F. Eisenbeis Supt. of Conservation WATER BEETLES The world is full of beetles. They live everywhere except in the oceans and in the polar regions. There are more of them than any other kind of insect. A quarter of a million species are known and new ones are being discovered every year. Whether it is a microscopic mushroom beetle a hundredth of an inch long, or a giant six-inch Hercules beetle from South America, it can be recognized by its wings. The upper pair forms a hard shell curving like a shield over the thin folded lower wings and the abdomen. In flight, the upper pair is extended like the wings of an airplane and the lower two become buzzing propellers.
NIST: NIF - Water Sensitivity
Water Sensitivity. Neutrons are extremely sensitive to small amounts of water. To quantify and calibrate this sensitivity we ...
Conventional Storage Water Heaters
Conventional storage water heaters remain the most popular type of water heating system for homes and buildings.
ARM: Microwave Radiometer data (MWR Profiles - QME), water vapor, temp, cloud liquid water, precip water retrievals
DOE Data Explorer (OSTI)
Microwave Radiometer data (MWR Profiles - QME), water vapor, temp, cloud liquid water, precip water retrievals
Maria Cadeddu
National Fuel - Large Non-Residential Conservation Program | Department of
National Fuel - Large Non-Residential Conservation Program National Fuel - Large Non-Residential Conservation Program National Fuel - Large Non-Residential Conservation Program < Back Eligibility Commercial Industrial Institutional Local Government Nonprofit Schools Savings Category Heating & Cooling Commercial Heating & Cooling Heating Home Weatherization Construction Commercial Weatherization Design & Remodeling Other Manufacturing Appliances & Electronics Water Heating Maximum Rebate Commercial Custom Rebates: $200,000 Industrial Custom Rebates: $5,000,000 Program Info State New York Program Type Utility Rebate Program Rebate Amount Custom Rebates: $15/Mcf x the gas savings or 50% of the total project cost Unit Heater: $1000 Hot Air Furnace: $500 Low Intensity Infrared Heating: $500 Programmable Thermostat: $25
. Reclaimed Water As people use water, a wastewater stream is produced. Once cleaned to acceptable standards and is available as reclaimed water. #12;20 New growth in central Arizona will produce significant quantities to return for wastewater treatment51 . Of the reclaimed water produced, 30% is assumed available to meet
Gelt, Joe
Reduction of Water Use in Wet FGD Systems
Reduction of WateR use in Wet fGd Reduction of WateR use in Wet fGd systems Background Coal-fired power plants require large volumes of water for efficient operation, primarily for cooling purposes. Public concern over water use is increasing, particularly in water stressed areas of the country. Analyses conducted by the U.S. Department of Energy's National Energy Technology Laboratory predict significant increases in power plant freshwater consumption over the coming years, encouraging the development of technologies to reduce this water loss. Power plant freshwater consumption refers to the quantity of water withdrawn from a water body that is not returned to the source but is lost to evaporation, while water withdrawal refers to the total quantity of water removed from a water source.
Taking the 'Large' out of Large Hadron Collider: Computational Breakthrough
Home » News & Publications » News » Science News » Taking the 'Large' out of Large Hadron Collider Taking the 'Large' out of Large Hadron Collider Computational breakthrough hastens modeling of 'tabletop accelerators' August 9, 2010 | Tags: Accelerator Science Contact: Margie Wylie | email@example.com | 510-486-7421 mori1 This 3D simulation shows how laser pulses create plasma wakes that propel electrons forward, much as a surfer is propelled forward by an ocean wave. Laser wakefield acceleration promises electron accelerators that are thousands of times more powerful than, yet a fraction the size of, conventional radio frequency devices. Particle accelerators like the Large Hadron Collider (LHC) at CERN are the big rock stars of high-energy physics-really big. The LHC cost nearly
Methyl quantum tunneling and nitrogen-14 NQR NMR studies using a SQUID magnetic resonance spectrometer
Nuclear Magnetic Resonance (NMR) and Nuclear Quadrupole Resonance (NQR) techniques have been very successful in obtaining molecular conformation and dynamics information. Unfortunately, standard NMR and NQR spectrometers are unable to adequately detect resonances below a few megahertz due to the frequency dependent sensitivity of their Faraday coil detectors. For this reason a new spectrometer with a dc SQUID (Superconducting Quantum Interference Device) detector, which has no such frequency dependence, has been developed. Previously, this spectrometer was used to observe {sup 11}B and {sup 27}Al NQR resonances. The scope of this study was increased to include {sup 23}Na, {sup 51}V, and {sup 55}Mn NQR transitions. Also, a technique was presented to observe {sup 14}N NQR resonances through cross relaxation of the nitrogen polarization to adjacent proton spins. When the proton Zeeman splitting matches one nitrogen quadrupoler transition the remaining two {sup 14}N transitions can be detected by sweeping a saturating rf field through resonance. Additionally, simultaneous excitation of two nitrogen resonances provides signal enhancement which helps to connect transitions from the same site. In this way, nitrogen-14 resonances were observed in several amino acids and polypeptides. This spectrometer has also been useful in the direct detection of methyl quantum tunneling splittings at 4.2 K. Tunneling, frequencies of a homologous series of carboxylic acids were measured and for solids with equivalent crystal structures, an exponential correlation between the tunneling frequency and the enthalpy of fusion is observed. This correlation provides information about the contribution of intermolecular interactions to the energy barrier for methyl rotation.
Black, B.E. [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry]|[Lawrence Berkeley Lab., CA (United States)
The U.S. Department of Energy is evaluating the Baker-Barry Tunnel as a potential GATEWAY Demonstrations project for deployment of solid-state lighting (SSL) technology. The National Park Service views this project as a possible proving ground and template for implementation of light-emitting diode (LED) luminaires in other tunnels, thereby expanding the estimated 40% energy savings from 132 MWh/yr to a much larger figure nationally. Most of the energy savings in this application is attributable to the instant-restrike capability of LED products and to their high tolerance for frequent on/off switching, used here to separately control either end of the tunnel during daytime hours. Some LED luminaires rival or outperform their high-intensity discharge (HID) counterparts in terms of efficacy, but options are limited, and smaller lumen packages preclude true one-for-one equivalence. However, LED products continue to improve in efficacy and affordability at a rate unmatched by other light source technologies; the estimated simple payback period of eight years (excluding installation costs and maintenance savings) can be expected to improve with time. The proposed revisions to the existing high-pressure sodium (HPS) lighting system would require slightly increased controls complexity and significantly increased luminaire types and quantities. In exchange, substantial annual savings (from reduced maintenance and energy use) would be complemented by improved quantity and quality of illumination. Although advanced lighting controls could offer additional savings, it is unclear whether such a system would prove cost-effective; this topic may be explored in future work.
INTRODUCTION Most estimates of abundance of large baleen whales,
Greenland waters are more than 10 years old. A series of aerial surveys of large baleen whales in West of the aerial survey in July and August 1993 resulted in an uncorrected estimate of 599 (95% CI 237-1,512) (Kingsley and Witting, 2001) and an aerial photographic survey in July through October 2002 and August
Laidre, Kristin L.
Tunneling dynamics and phase transition of a Bose-Fermi mixture in a double well
The coherent nonlinear tunneling dynamics of a boson-fermion mixture in a double-well potential is studied in this paper. Four types of phase are found for the mixture. The first one is two species localizing in different potential wells. The second one is two species coexisting in the same well. The third one is two species equally populated in two wells. The fourth one is one species equally populated in two wells while the other species is in one well. The phase transitions among these four states have been investigated. The interspecies and intraspecies interactions as well as bosonic and fermionic numbers can dramatically affect these phase transitions.
Qi Pengtang; Duan Wenshan [Department of Physics, Northwest Normal University, Lanzhou, 730070 (China)
Structure and Reactions of Carbon and Hydrogen on Ru(0001): A Scanning Tunneling Microscopy Study
The interaction between carbon and hydrogen atoms on a Ru(0001) surface was studied using scanning tunneling microscopy (STM), Density Functional Theory (DFT) and STM image calculations. Formation of CH species by reaction between adsorbed H and C was observed to occur readily at 100 K. When the coverage of H increased new complexes of the form CH+nH (n = 1, 2 and 3) were observed. These complexes, never observed before, might be precursors for further hydrogenation reactions. DFT analysis reveals that a considerable energy barrier exists for the CH+H {yields} CH{sub 2} reaction.
Shimizu, Tomoko K.; Mugarza, Aitor; Cerda, Jorge; Salmeron, Miquel
Tunneling and traversal of ultracold three-level atoms through vacuum-induced potentials
The passage of ultracold three-level atoms through the potential induced by the vacuum cavity mode is discussed using cascade atomic configuration. We study the tunneling or traversal time of the ultracold atoms via a bimodal high-Q cavity. It is found that the phase time, which may be considered as a measure for the time required to traverse the cavity, exhibits superclassical and subclassical behaviors. Further, the dark states and interference effects in cascade atomic configuration may influence the passage time of the atom through the cavity.
Badshah, Fazal; Irfan, Muhammad; Qamar, Shahid [Department of Physics and Applied Mathematics, Pakistan Institute of Engineering and Applied Sciences, Nilore, Islamabad 45650 (Pakistan); Qamar, Sajid [Department of Physics, COMSATS Institute of Information Technology, Islamabad (Pakistan)
Nanometer-scale tunnel formation in metallic glass by helium ion irradiation
We have shown that upon high fluence helium ion irradiation, metallic glass Cu{sub 50}Zr{sub 45}Ti{sub 5} becomes highly porous at the depth of the helium projected range. The resulting porous region is characterized by the formation of a tunnel like structure and self-linkage of nanometer size gas bubbles. Furthermore, the irradiation leads to the formation of nanometer size Cu{sub x}Zr{sub y} crystals that are randomly distributed. The results of this study indicate that the He-filled bubbles have attractive interactions and experience considerable mobility. Movement of the bubbles is believed to be assisted by ballistic collisions.
Shao Lin [Department of Nuclear Engineering, Texas A and M University, College Station, Texas 77843 (United States); Materials Science and Engineering Program, Texas A and M University, College Station, Texas 77843 (United States); Gorman, Brian P. [Department of Metallurgical and Materials Engineering, Colorado School of Mines, Golden, Colorado 80401 (United States); Aitkaliyeva, Assel [Materials Science and Engineering Program, Texas A and M University, College Station, Texas 77843 (United States); David Theodore, N. [CHD-Fab, Freescale Semiconductor, Inc., Chandler, Arizona 85224 (United States); Xie Guoqiang [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)
An Experiment Study of the Propagation of Radio Waves in a Scaled Model of Long-Wall Coal Mining Tunnels
A long-wall coal mining tunnel is the most important working area in a coal mine. It has long been realized that radio communications can improve both productivity and safety in this dangerous area. Hence, many attempts to use radio communications in such an environment have been made. Unfortunately, no radio system has satisfactorily provided communication services there, which, we believe, is partially due to poor understanding of the propagation characteristics of radio waves in the long-wall mining tunnel. To have deeper physical insight into the propagation problem, a scaled model of the long-wall mining tunnel was built, and the propagation characteristics of UHF radio waves were measured. The experiment and the measured results are presented and discussed.
Han, G.R.; Zhang, W.M.; Zhang, Y.P. [Shanxi University, Taiyuan (China)
Impact of metal nano layer thickness on tunneling oxide and memory performance of core-shell iridium-oxide nanocrystals
The impact of iridium-oxide (IrO{sub x}) nano layer thickness on the tunneling oxide and memory performance of IrO{sub x} metal nanocrystals in an n-Si/SiO{sub 2}/Al{sub 2}O{sub 3}/IrO{sub x}/Al{sub 2}O{sub 3}/IrO{sub x} structure has been investigated. A thinner (1.5 nm) IrO{sub x} nano layer has shown better memory performance than that of a thicker one (2.5 nm). Core-shell IrO{sub x} nanocrystals with a small average diameter of 2.4 nm and a high density of {approx}2 x 10{sup 12}/cm{sup 2} have been observed by scanning transmission electron microscopy. The IrO{sub x} nanocrystals are confirmed by x-ray photoelectron spectroscopy. A large memory window of 3.0 V at a sweeping gate voltage of {+-}5 V and 7.2 V at a sweeping gate voltage of {+-} 8 V has been observed for the 1.5 nm-thick IrO{sub x} nano layer memory capacitors with a small equivalent oxide thickness of 8 nm. The electrons and holes are trapped in the core and annular regions of the IrO{sub x} nanocrystals, respectively, which is explained by Gibbs free energy. High electron and hole-trapping densities are found to be 1.5 x 10{sup 13}/cm{sup 2} and 2 x 10{sup 13}/cm{sup 2}, respectively, due to the small size and high-density of IrO{sub x} nanocrystals. Excellent program/erase endurance of >10{sup 6} cycles and good retention of 10{sup 4} s with a good memory window of >1.2 V under a small operation voltage of {+-} 5 V are obtained. A large memory size of >10 Tbit/sq. in. can be designed by using the IrO{sub x} nanocrystals. This study is not only important for the IrO{sub x} nanocrystal charge-trapping memory investigation but it will also help to design future metal nanocrystal flash memory.
Banerjee, W.; Maikap, S. [Thin Film Nano Tech. Lab., Department of Electronic Engineering, Chang Gung University, Tao-Yuan, Taiwan 333, Taiwan (China); Tien, T.-C. [Material Research Laboratories, Industrial Technology Research Institute, Hsinchu, Taiwan 310, Taiwan (China); Li, W.-C.; Yang, J.-R. [Department of Materials Science and Engineering, National Taiwan University, Taipei 106, Taiwan (China)
Use of Degraded Water Sources as Cooling Water in Power Plants
In electricity production, nearly all thermal power plants reject heat either to a large body of water (once-through cooling) or to the atmosphere via wet cooling towers — the predominant form of cooling in California. These towers, however, use considerable quantities of water. Competing state demands for freshwater have forced California thermal power plants to consider alternative cooling water supplies, though the availability of such supplies and data on their use and impact is limited. In fac...
FULL-SCALE, WIND TUNNEL AND CFD WIND ENGINEERING STUDIES A variety of methods can be used to obtain wind engineering design information. These include
FULL-SCALE, WIND TUNNEL AND CFD WIND ENGINEERING STUDIES A variety of methods can be used to obtain wind engineering design information. These include codes of practice, full-scale, wind tunnel are listed in the table below: Table 1. Relative advantages and disadvantages of wind engineering techniques
Savory, Eric
Momentum-resolved tunneling between a Luttinger liquid and a two-dimensional electron gas S. A. Grigera and A. J. Schofield
Momentum-resolved tunneling between a Luttinger liquid and a two-dimensional electron gas S. A consider momentum resolved tunneling between a Luttinger liquid and a two-dimensional electron gas on both the Luttinger liquid and the two-dimensional electron gas. We show that there are six dispersing
Grigera, Santiago
A Wind Tunnel and Theoretical Study of the Melting Behavior of Atmospheric Ice Particles. IV: Experiment and Theory for Snow Flakes
An experiment in the Mainz vertical Cloud Tunnel is described in which natural and laboratory-made aggregates of snow crystals (snow flakes) were melted under free fall conditions in the vertical air stream of the tunnel, which was allowed to ...
S. K. Mitra; O. Vohl; M. Ahr; H. R. Pruppacher
Partnering to Save Water
Partnering Partnering to Save Water Phill Consiglio Southern California Edison What We Are Going to Discuss * A Little Bit About Water * The Energy Cost of Water * Water Technologies * What We Have Done * Where We Are Going A Little Bit About Water *The Earth Has A Finite Supply Of Fresh Water. - Water Is Stored In Aquifers, Surface Waters And The Atmosphere - Sometimes Oceans Are Mistaken For Available Water, But The Amount Of Energy Needed To Convert Saline Water To Potable Water Is Prohibitive Today *This Has Created A Water Crisis Due To: - Inadequate Access To Safe Drinking Water For About 884 Million People - Inadequate Access To Water For Sanitation And Waste Disposal For 2.5 Billion People - Groundwater Overdrafting (Excessive Use) Leading To Diminished Agricultural Yields
Alignment-dependent fluorescence emission induced by tunnel ionization of carbon dioxide from lower-lying orbitals
We show that fluorescence emission induced by strong field tunnel ionization of carbon dioxide from its lower-lying orbitals exhibits a peculiar molecular alignment dependence. The experimentally measured alignment-dependence of the fluorescence agrees with the alignment-dependence of the ionization probability calculated in the framework of the strong field approximation. Our results demonstrate the feasibility of an all-optical approach for shedding more light on the ionization mechanisms of molecules from their lower-lying orbitals in tunnel ionization regime.
Yao, Jinping; Jia, Xinyan; Hao, Xiaolei; Zeng, Bin; Jing, Chenrui; Chu, Wei; Ni, Jielei; Zhang, Haisu; Xie, Hongqiang; Zhang, Chaojin; Zhao, Zengxiu; Chen, Jing; Liu, Xiaojun; Cheng, Ya; Xu, Zhizhan
Giromill wind tunnel test and analysis. Volume I. Executive summary. Final report, June 1976--October 1977
The study described herein is a continuation of the Giromill investigation in which a wind tunnel test of a model Giromill rotor was performed. The primary objective of the wind tunnel test was to obtain data for comparison with the Larsen cyclogiro vortex theory program employed for predicting the Giromill performance. The model had a rotor diameter of 7 ft. (2.13 meters) and a solidity (total blade area divided by rotor span times diameter) of 0.3. This was achieved by a three bladed rotor having blade chords of 8.4 in. (21.3 cm) and a span of 5 ft. (1.52 meters). The blades were modulated by use of replaceable cams, that simulated the various operating conditions, and a push rod arrangement connected to a bellcrank about the blade pivot point. Rotor RPM control was achieved with an electric motor/generator that could be used to either drive the rotor or absorb the rotor power to maintain RPM.
Kinetics of tunneling electron transfer between antimorphous defects in optical crystals with mobile cations
The experimental data on the transient optical absorption of wide-band-gap optical crystals of lithium borates Li{sub 2}B{sub 4}O{sub 7}, LiB{sub 3}O{sub 5}, and Li{sub 6}Gd(BO{sub 3}){sub 3} and potassium (KH{sub 2}PO{sub 4} (KDP)) and ammonium (NH{sub 4}H{sub 2}PO{sub 4} (ADP)) dihydrogen phosphates in the visible and ultraviolet spectral regions are analyzed using the theory of diffusion-controlled tunneling recombination. A nanosecond pulsed radiation action on these crystals is shown to form defect pairs, such as polaron-type hole centers and electron centers based on interstitial cations. The relaxation kinetics of these centers over a wide time range of 10{sup -8}-10 s is described by a proposed model of tunneling electron transfer between antimorphous defects in the cation sublattice under the thermally stimulated mobility of recombination partners. The numerical values of the kinetic parameters are determined and the time dependences of the reaction rate constants are calculated for all crystals under study. As a result, the dynamics of change in the optical properties of these crystals under a pulsed radiation action can be simulated.
Ogorodnikov, I. N., E-mail: firstname.lastname@example.com; Kiseleva, M. S. [Ural Federal University (Russian Federation)
Patency of Femoral Tunneled Hemodialysis Catheters and Factors Predictive of Patency Failure
Purpose: To determine the patency rates of and factors associated with increased risk of patency failure in patients with femoral vein tunneled hemodialysis catheters. Methods: All femoral tunneled catheter insertions from 1996 to 2006 were reviewed, during which time 123 catheters were inserted. Of these, 66 were exchanges. Patients with femoral catheter failure versus those with femoral catheter patency were compared. Confounding factors, such as demographic and procedural factors, were incorporated and assessed using univariate and multivariable Cox proportional hazards regression analyses. Results: Mean catheter primary patency failure time was 96.3 days (SE 17.9 days). Primary patency at 30, 60, 90, and 180 days was 53.8%, 45.4%, 32.1%, and 27.1% respectively. Crude rates of risk of catheter failure did not suggest a benefit for patients receiving catheters introduced from one side versus the other, but more cephalad location of catheter tip was associated with improved patency. Multivariate analysis showed that patients whose catheters were on the left side (p = 0.009), were of increasing age at the time of insertion (p = 0.002) and that those who had diabetes (p = 0.001) were at significantly greater risk of catheter failure. The catheter infection rate was 1.4/1000 catheter days. Conclusion: Patients who were of a more advanced age and had diabetes were at greater risk of femoral catheter failure, whereas those who received femoral catheters from the right side were less at risk of catheter failure.
Burton, Kirsteen R. [University Health Network, University of Toronto, Department of Medical Imaging, Division of Vascular and Interventional Radiology (Canada); Guo, Lancia L. Q. [University of Calgary, Department of Radiology (Canada); Tan, Kong T.; Simons, Martin E.; Sniderman, Kenneth W.; Kachura, John R.; Beecroft, John R.; Rajan, Dheeraj K., E-mail: firstname.lastname@example.com [University Health Network, University of Toronto, Department of Medical Imaging, Division of Vascular and Interventional Radiology (Canada)
Spin-1 atoms in optical superlattices: Single-atom tunneling and entanglement
We examine spinor Bose-Einstein condensates in optical superlattices theoretically using a Bose-Hubbard Hamiltonian that takes spin effects into account. Assuming that a small number of spin-1 bosons is loaded in an optical potential, we study single-particle tunneling that occurs when one lattice site is ramped up relative to a neighboring site. Spin-dependent effects modify the tunneling events in a qualitative and quantitative way. Depending on the asymmetry of the double well, different types of magnetic order occur, making the system of spin-1 bosons in an optical superlattice a model for mesoscopic magnetism. We use a double-well potential as a unit cell for a one-dimensional superlattice. Homogeneous and inhomogeneous magnetic fields are applied, and the effects of the linear and the quadratic Zeeman shifts are examined. We also investigate the bipartite entanglement between the sites and construct states of maximal entanglement. The entanglement in our system is due to both orbital and spin degrees of freedom. We calculate the contribution of orbital and spin entanglements and show that the sum of these two terms gives a lower bound for the total entanglement.
Wagner, Andreas; Bruder, Christoph; Demler, Eugene [Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Department of Physics, Harvard University, Cambridge, Massachusetts 02138 (United States)
Tunneling probability for the birth of an asymptotically de Sitter universe
In the present work, we quantize a closed Friedmann-Robertson-Walker model in the presence of a positive cosmological constant and radiation. It gives rise to a Wheeler-DeWitt equation for the scale factor which has the form of a Schroedinger equation for a potential with a barrier. We solve it numerically and determine the tunneling probability for the birth of a asymptotically DeSitter, inflationary universe, initially, as a function of the mean energy of the initial wave function. Then, we verify that the tunneling probability increases with the cosmological constant, for a fixed value of the mean energy of the initial wave function. Our treatment of the problem is more general than previous ones, based on the WKB approximation. That is the case because we take into account the fact that the scale factor (a) cannot be smaller than zero. It means that, one has to introduce an infinity potential wall at a=0, which forces any wave packet to be zero there. That condition introduces new results, in comparison with previous works.
Acacio de Barros, J. [CSLI, 220 Panama Street, Stanford University, Stanford, California 94305-4115 (United States); Correa Silva, E. V.; Monerat, G. A.; Oliveira-Neto, G. [Departamento de Matematica e Computacao, Faculdade de Tecnologia, Universidade do Estado do Rio de Janeiro, Rodovia Presidente Dutra Km 298, Polo Industrial, CEP 27537-000, Resende-RJ (Brazil); Ferreira Filho, L. G. [Departamento de Mecanica e Energia, Faculdade de Tecnologia, Universidade do Estado do Rio de Janeiro, Rodovia Presidente Dutra Km 298, Polo Industrial, CEP 27537-000, Resende-RJ (Brazil); Romildo, P. Jr. [Departamento de Fisica, Instituto de Ciencias Exatas, Universidade Federal de Juiz de Fora, CEP 36036-330, Juiz de Fora, Minas Gerais (Brazil)
Carderock Circulating Water Channel | Open Energy Information
Circulating Water Channel Circulating Water Channel Jump to: navigation, search Basic Specifications Facility Name Carderock Circulating Water Channel Overseeing Organization United States Naval Surface Warfare Center Hydrodynamic Testing Facility Type Channel Length(m) 18.3 Beam(m) 6.7 Depth(m) 2.7 Water Type Freshwater Cost(per day) Contact POC Special Physical Features The Circulating Water Channel is a vertical plane, open to the atmosphere test section with a free surface in a closed recirculating water circuit, variable speed, rectangular cross-sectional shape facility. There are 10 large viewing windows on either side of the test section at different elevations and 9 in the bottom; movable bridge spans the test section for ease and versatility in mounting models, rigging bridge is capable of taking towing loads at any one of numerous points up to 35,584 N
China's Water Resources: Crisis and Opportunity
China's Water Resources: Crisis and Opportunity China's Water Resources: Crisis and Opportunity Speaker(s): Ma Jun Date: June 17, 2002 - 12:00pm Location: Bldg. 90 The rivers in China, and the hundreds of millions who depend on them, are in trouble. A water crisis looms large in most parts of China. In his book, China Water Crisis, Ma Jun traces 4,000 years of the history of China's watersheds, and their mis/management. Armed with scientific data and compelling stories, Ma reveals the causes and character of the looming ecological disaster. His book has been quoted in The Economist and many western media. Limited water resources pose a major threat to social and economic development in the 21st century. Three Gorges Dam and redirecting water from south to north occupy the main focus of the efforts to increase
Charge trapping characteristics of Au nanocrystals embedded in remote plasma atomic layer-deposited Al{sub 2}O{sub 3} film as the tunnel and blocking oxides for nonvolatile memory applications
Remote plasma atomic layer deposited (RPALD) Al{sub 2}O{sub 3} films were investigated to apply as tunnel and blocking layers in the metal-oxide-semiconductor capacitor memory utilizing Au nanocrystals (NCs) for nonvolatile memory applications. The interface stability of an Al{sub 2}O{sub 3} film deposited by RPALD was studied to observe the effects of remote plasma on the interface. The interface formed during RPALD process has high oxidation states such as Si{sup +3} and Si{sup +4}, indicating that RPALD process can grow more stable interface which has a small amount of fixed oxide trap charge. The significant memory characteristics were also observed in this memory device through the electrical measurement. The memory device exhibited a relatively large memory window of 5.6 V under a 10/-10 V program/erase voltage and also showed the relatively fast programming/erasing speed and a competitive retention characteristic after 10{sup 4} s. These results indicate that Al{sub 2}O{sub 3} films deposited via RPALD can be applied as the tunnel and blocking oxides for next-generation flash memory devices.
Lee, Jaesang; Kim, Hyungchul; Park, Taeyong; Ko, Youngbin; Ryu, Jaehun; Jeon, Heeyoung; Park, Jingyu; Jeon, Hyeongtag [Department of Nano-scale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Division of Materials Science and Engineering, Hanyang University, Seoul 133-791, Korea and R and D Division, Hynix Semiconductor, Inc., Icheon, Gyeonggi-do 467-701 (Korea, Republic of); Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Division of Materials Science and Engineering, Hanyang University, Seoul 133-791, Korea and R and D Division, Hynix Semiconductor, Inc., Icheon, Gyeonggi-do 467-701 (Korea, Republic of); Department of Nano-scale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Department of Nano-scale Semiconductor Engineering, Hanyang University, Seoul 133-791, Korea and Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of)
Biofuel impacts on water.
Sandia National Laboratories and General Motors Global Energy Systems team conducted a joint biofuels systems analysis project from March to November 2008. The purpose of this study was to assess the feasibility, implications, limitations, and enablers of large-scale production of biofuels. 90 billion gallons of ethanol (the energy equivalent of approximately 60 billion gallons of gasoline) per year by 2030 was chosen as the book-end target to understand an aggressive deployment. Since previous studies have addressed the potential of biomass but not the supply chain rollout needed to achieve large production targets, the focus of this study was on a comprehensive systems understanding the evolution of the full supply chain and key interdependencies over time. The supply chain components examined in this study included agricultural land use changes, production of biomass feedstocks, storage and transportation of these feedstocks, construction of conversion plants, conversion of feedstocks to ethanol at these plants, transportation of ethanol and blending with gasoline, and distribution to retail outlets. To support this analysis, we developed a 'Seed to Station' system dynamics model (Biofuels Deployment Model - BDM) to explore the feasibility of meeting specified ethanol production targets. The focus of this report is water and its linkage to broad scale biofuel deployment.
Tidwell, Vincent Carroll; Malczynski, Leonard A.; Sun, Amy Cha-Tien
Lightning Safety and Large Stadiums
When lightning threatens an outdoor activity, it is usually postponed so that people may seek a safe location. When lightning threatens a large outdoor stadium, the game or event itself is usually postponed, but it is often difficult to ensure ...
Joel Gratz; Erik Noble
Large Consistent Geometric Landmark Maps
The autonomous operation of an intelligent service robot in practical applications requires that the robot builds up a map of the environment by itself, even for large environments like supermarkets. This paper presents a solution to the problem of building ...
Wolfgang D. Rencken; Wendelin Feiten; Martin Soika
Department of Energy assessment of the Large Hadron Collider
This report summarizes the conclusions of the committee that assessed the cost estimate for the Large Hadron Collider (LHC). This proton-proton collider will be built at CERN, the European Laboratory for Particle Physics near Geneva, Switzerland. The committee found the accelerator-project cost estimate of 2.3 billion in 1995 Swiss francs, or about $2 billion US, to be adequate and reasonable. The planned project completion date of 2005 also appears achievable, assuming the resources are available when needed. The cost estimate was made using established European accounting procedures. In particular, the cost estimate does not include R and D, prototyping and testing, spare parts, and most of the engineering labor. Also excluded are costs for decommissioning the Large Electron-Positron collider (LEP) that now occupies the tunnel, modifications to the injector system, the experimental areas, preoperations costs, and CERN manpower. All these items are assumed by CERN to be included in the normal annual operations budget rather than the construction budget. Finally, contingency is built into the base estimate, in contrast to Department of Energy (DOE) estimates that explicitly identify contingency. The committee`s charge, given by Dr. James F. Decker, Deputy Directory of the DOE Office of Energy Research, was to understand the basis for the LHC cost estimate, identify uncertainties, and judge the overall validity of the estimate, proposed schedule, and related issues. The committee met at CERN April 22--26, 1996. The assessment was based on the October 1995 LHC Conceptual Design Report or ``Yellow Book,`` cost estimates and formal presentations made by the CERN staff, site inspection, detailed discussions with LHC technical experts, and the committee members` considerable experience.
Magnetohydrodynamic sea water propulsion
An experimental and theoretical investigation of a large scale MHD propulsor has been undertaken whose objectives are to (1) investigate the transient and steady state performance of the thruster over operating parameter ranges that are compatible with achievement of high efficiency, (2) to quantify the principal loss mechanisms within the thruster and (3) to obtain preliminary hydroacoustic data. The performance of the thruster was first investigated theoretically with a 3-D code to quantify the loss mechanisms and identify experimental parameter ranges of interest. The loss mechanisms of interest are ohmic losses within the channel and those resulting from electrical currents at the entrance and exit of the thruster, and enhanced frictional losses. The analysis indicated that the relative importance of the loss mechanisms was a function of the thruster design and operating parameters. The experimental investigation of the large scale propulsor is being conducted on a sea water test facility that was designed to match the capabilities of a large 6-T superconducting magnet. The facility design was such that {approximately}90{degrees} of all losses occurred within the propulsion test train (inlet nozzle, propulsor and diffuser) thus facilitating isolation of the loss mechanisms. The test thruster itself is heavily instrumented to provide local measurements of velocity, pressure, and electric fields. The predicted overall thruster performance and value of the loss mechanisms will be compared with measured values. Comparisons will also be presented of the voltage gradients between electrodes, overall thruster efficiency, axial pressure gradients across the propulsor, change in velocity profiles, axial and vertical current distributions and exit distribution of the electrolytic gases.
Petrick, M.; Thomas, A.; Genens, L.; Libera, J.; Nietert, R.; Bouillard, J.; Pierson, E.; Hill, D.; Picologlou, B.; Ohlsson, O.; Kasprzyk, T.; Berry, G.
Water Distribution System Recommendations for the 2008 Title- 24 Residential Building Energy Efficiency Standards .. 4 Multi-FamilyWater Distribution System Recommendations for the 2008 Title- 24 Residential Building Energy Efficiency Standards 11 Multi-FamilyWater Distribution System Recommendations for the 2008 Title- 24 Residential Building Energy Efficiency Standards 48 Multi-Family
Water heater heat reclaimer
This invention relates to the conservation of energy in a domestic gas water heater by utilizing the hot exhaust gases in a gas water heater for the preheating of the incoming unheated water into the water heater. The exhaust gases from a domestic gas water heater carry wasted heat and the present invention provides a mean to reclaim part of the wasted heat for the preheating of the incoming unheated water during hot water usage periods. During non hot water usage periods the heat in the exhaust gases is not reclaimed to prevent overheating of the water and also to prevent the formation of water deposit in the preheating assembly or heat reclaimer. During the non hot water usage periods the heat produced in the water heater is normally needed only to maintain the desired water temperature of the stored water in the water tank of the water heater. Due to the rapid heating or recovery rate, the present invention enables the use of a smaller water heater. The use of a smaller water heater reduces the normal heat loss from the stored hot water thereby further reduces energy consumption.
Wie, C.T.
Produced Water Management and Beneficial Use
Large quantities of water are associated with the production of coalbed methane (CBM) in the Powder River Basin (PRB) of Wyoming. The chemistry of co-produced water often makes it unsuitable for subsequent uses such as irrigated agriculture. However, co-produced waters have substantial potential for a variety of beneficial uses. Achieving this potential requires the development of appropriate water management strategies. There are several unique characteristics of co-produced water that make development of such management strategies a challenge. The production of CBM water follows an inverse pattern compared to traditional wells. CBM wells need to maintain low reservoir pressures to promote gas production. This need renders the reinjection of co-produced waters counterproductive. The unique water chemistry of co-produced water can reduce soil permeability, making surface disposal difficult. Unlike traditional petroleum operations where co-produced water is an undesirable by-product, co-produced water in the PRB often is potable, making it a highly valued resource in arid western states. This research project developed and evaluated a number of water management options potentially available to CBM operators. These options, which focus on cost-effective and environmentally-sound practices, fall into five topic areas: Minimization of Produced Water, Surface Disposal, Beneficial Use, Disposal by Injection and Water Treatment. The research project was managed by the Colorado Energy Research Institute (CERI) at the Colorado School of Mines (CSM) and involved personnel located at CERI, CSM, Stanford University, Pennsylvania State University, the University of Wyoming, the Argonne National Laboratory, the Gas Technology Institute, the Montana Bureau of Mining and Geology and PVES Inc., a private firm.
Terry Brown; Carol Frost; Thomas Hayes; Leo Heath; Drew Johnson; David Lopez; Demian Saffer; Michael Urynowicz; John Wheaton; Mark Zoback
Water, Water Everywhere: How Can We Understand It?
... Science Afternoon. Water, Water Everywhere: How Can We Understand It? An exploration of water using physical models and computer simulation. ...
Water Rx - The Problem of Pharmaceuticals in Our Nation's Waters
IN OUR NATION'S WATERS intake via drinking water wastherapeutic dose and intake via drinking water was 150,000
Leitman, Melanie
Feature - WATER Tool Released
Water Assessment for Transportation Energy Resources (WATER) Tool Released Water Assessment for Transportation Energy Resources (WATER) Tool Released Argonne National Laboratory recently released an open access online tool called WATER (Water Assessment for Transportation Energy Resources), which quantifies water footprint of fuel production stages from feedstock production to conversion process for biofuel with county, state, and regional level spatial resolution. WATER provides analysis on water consumption and its impact on water quality. It contains biofuel pathways for corn grain ethanol, soybean biodiesel, and cellulosic ethanol produced from corn stover and wheat straw. Perennial grass (Switchgrass and Miscanthus) and forest wood residue-based biofuel pathways are currently under development. The WATER tool enables users to conduct pathway comparison, scenario development, and regional specific feedstock analysis in supporting of biofuel industry development and planning. It is available at http://water.es.anl.gov/.
Tankless Demand Water Heaters
Demand (tankless or instantaneous) water heaters have heating devices that are activated by the flow of water, so they provide hot water only as needed and without the use of a storage tank. They...
Review: Globalization of Water
Review: Globalization of Water: Sharing the Planet'sAshok K. Globalization of Water: Sharing the Planet's140) liters of virtual water (p. 15). This is one of the
Tennant, Matthew Aaron
H. , Groves D. California Water 2030: An Efficient Future,Preemption of California's Water Conservation Standards for2Epdf Biermayer P. Potential Water and Energy Savings from
Flow Distortion by a Solent Sonic Anemometer: Wind Tunnel Calibration and Its Assessment for Flux Measurements over Forest and Field
Main flow distortion effects caused by the sonic probe (i.e., deflection and attenuation/amplification of the wind vector) as a function of the azimuth angle of the incoming flow were examined by means of wind tunnel measurements at four ...
A. Grelle; A. Lindroth
Drop Shapes and Axis Ratio Distributions: Comparison between 2D Video Disdrometer and Wind-Tunnel Measurements
Comparisons of drop shapes between measurements made using 2D video disdrometer (2DVD) and wind-tunnel experiments are presented. Comparisons are made in terms of the mean drop shapes and the axis ratio distributions. Very close agreement of the ...
M. Thurai; V. N. Bringi; M. Szakáll; S. K. Mitra; K. V. Beard; S. Borrmann
Direct measurement of interfacial structure in epitaxial Gd2O3 on GaAs (001) using scanning tunneling microscopy
The epitaxial growth of Gd"2O"3 on GaAs (001) has given a low interfacial density of states, resulting in the demonstration of the first inversion-channel GaAs metal-oxide-semiconductor field-effect transistor. Motivated by the significance of this discovery, ... Keywords: Electronic information, GaAs, Gd2O3, Interfacial stacking, Scanning tunneling microscopy
Y. P. Chiu; M. C. Shih; B. C. Huang; J. Y. Shen; M. L. Huang; W. C. Lee; P. Chang; T. H. Chiang; M. Hong; J. Kwo
The Nuclear Regulatory Commission is seeking public comment on a study of how a truck cask for transporting spent nuclear fuel might perform in a severe tunnel fire. The report models the performance of the NAC International Model LWT (NAC) spent fuel cask under the conditions of the April 1982 fire in the Caldecott highway tunnel near Oakland, Calif., when a gasoline tanker carrying 8,800 gallons of gasoline overturned and caught fire. Severe, intense fires such as the Caldecott fire are extremely rare. However, they provide an opportunity to study how transportation packages might perform under very severe accident conditions. The results of this study strongly indicate that any radioactive release from the NAC model or a similar spent fuel shipping cask involved in a severe tunnel fire such as that of the Caldecott highway tunnel accident would be within regulatory limits. The peak internal temperatures predicted for the NAC cask in the analysis of the Caldecott fire scenario were not high enough to result in rupture of the fuel cladding (protective metal tubing around the fuel). Therefore, it would not be expected that any radioactive material (including spent nuclear fuel particles or fission products) would be released from the fuel rods. The maximum cask temperatures experienced around the lid, vent and drain ports exceeded the
unknown authors
Measuring charge trap occupation and energy level in CdSe/ZnS quantum dots using a scanning tunneling microscope
We use a scanning tunneling microscope to probe single-electron charging phenomena in individual CdSe/ZnS (core/shell) quantum dots (QDs) at room temperature. The QDs are deposited on top of a bare Au thin film and form a ...
Bulovic, Vladimir
Theory of tunneling magnetoresistance of an epitaxial FeMgOFe,,001... junction J. Mathon and A. Umerski
. Umerski Department of Mathematics, City University, London EC1V 0HB, United Kingdom Received 21 December is in excess of 1000% for an MgO barrier of 20 atomic planes and the spin polarization of the tunneling current atomic planes. All these results are explained qualitatively in terms of the Fe majority- and minority
Umerski, Andrey
FORCE SENSING IN SCANNING TUNNELING MICROSCOPY U. DURIG, J.K. GIMZEWSKI, D.W. POHL and R. SCHLITTLER
FORCE SENSING IN SCANNING TUNNELING MICROSCOPY U. DURIG, J.K. GIMZEWSKI, D.W. POHL and R, (1986) 930. [3] U. Durig, J.K. Gimzewski, and D.W. Pohl, Phys. Rev. Lett., in press. [4] J. Soler, A
Gimzewski, James
Comparing Large-Scale Hydrological Model Simulations to Observed Runoff Percentiles in Europe
Large-scale hydrological models describing the terrestrial water balance at continental and global scales are increasingly being used in earth system modeling and climate impact assessments. However, because of incomplete process understanding and ...
Lukas Gudmundsson; Lena M. Tallaksen; Kerstin Stahl; Douglas B. Clark; Egon Dumont; Stefan Hagemann; Nathalie Bertrand; Dieter Gerten; Jens Heinke; Naota Hanasaki; Frank Voss; Sujan Koirala
Large-Eddy Simulations of Strongly Precipitating, Shallow, Stratocumulus-Topped Boundary Layers
Large-eddy simulations that incorporate a size-resolving representation of cloud water are used to study the effect of heavy drizzle on PBL structure. Simulated surface precipitation rates average about 1 mm day?1. Heavily drizzling simulations ...
Bjorn Stevens; William R. Cotton; Graham Feingold; Chin-Hoh Moeng
Large-Scale Vertical Eddy Diffusion in the Main Pycnocline of the Central North Pacific
Indirect procedures are used to estimate the latitudinal distribution of the large-scale vertical eddy diffusivity coefficient in the main pycnocline from the interannual change in T?, ?? structure of the water column in the central midlatitude ...
Warren White; Robert Bernstein
Drinking Water Standards
This publication explains the federal safety standards for drinking water provided by public water supply systems. It discusses the legal requirements for public water supplies, the maximum level allowed for contaminants in the water, and the potential health effects of each contaminant regulated. People who use water from private sources such as wells can also use these standards as a guide in checking whether their water is safe.
Hanford as a site for large accelerators
The Ramsey Panel recommended that two very large accelerators be constructed during the next few years to meet urgent U. S. needs in high energy physics. Two studies have been made. The Lawrence Radiation Laboratory at Berkeley has studied a 200 to 300 BeV accelerator, while the Brooknaven National Laboratory on Long Island has made an analysis of a still larger accelerator--600 to 800 BeV. This special report is in response to a request for information on the suitability of the Atomic Energy Commission' s Hanford Project as a site for a large accelerator. Using criteria recommended by Lawrence and Brookhaven, the Hanford site offers significant economic advantages both in original installed cost and in annual operating expense. These advantages are: (1) Land--Hanford has available more than 150 square miles of govermnentowned land that readily meets topographic, geologic, and seismic criteria; (2) Power--- Hanford has surplus electrical capacity already installed to meet the demands of the largest accelerator--- at the lowest rates in the U. S. This alone offers an annual savings of several million dollars over any other location; (3) Water--- the Columbia River offers the largest supply of pure, cold water in the U. S.; there are excellent surplus reactor water plants available; (4) Transportation---four major railroads have direct connections to the Hanford Project rail system; multi- 1000-ton barge service is also available; (5) manpower---a high level of scientific and technical personnel as well as construction and craft labor is already in residence; (6) Services---complete support-type services, such as industrial shops, bus transportation, radiation protection, and plant security, are immediately available; and (7) Community--the area has an exceptionally high educational level, equal to the outstanding areas of the U. S. At the present time, the Hanford location has some disadvantages according to the cited criteria. These are: (1) lack of proximity to a university; (2) lack of a major jet airport; and (3) relative isolation from a major metropolitan area. The first two are even now under vigorous study and action by both state and local bodies. The third, though often a disadvantage, appears to have considerable appeal to many. In total, the many tangible assets of the Hanford Project offer tremendous potential dollar savings to the Government. The shutdown of preduction reactors makes many millions of dollars worth of excellent support facilities and manpower readily available. The minor disadvantages can be met almost entirely by the state and community. (auth)
Leonard, B.R. Jr.
Carbon and Water Resource Management for Water Distribution Systems
4 April, 2013. (4) 2010 Water Use Survey Summary Estimates –State Totals; Texas Water Development Board: Austin, TX,indicators for urban water systems. Urban Water. 2004, 4,
Hendrickson, Thomas Peter
Ultraviolet Water Treatment
UV Ray of Hope for Safer Drinking Water. ... It is not, however, too soon for the American Water Works Association to express its appreciation. ...
NETL: Water - Energy Interface
Home > Technologies > Coal & Power Systems > Innovations for Existing Plants > Water - Energy Interface Innovations for Existing Plants Water - Energy Interface Previous Next...
Membranes for Clean Water
Membranes for Clean Water. Summary: ... Description: Impact. Access to affordable, clean water is vital to the nation's economic growth and security. ...
Drinking Water Problems: Copper
High levels of copper in drinking water can cause health problems. This publication explains the effects of copper in water and methods of removing it. 4 pp.
Dozier, Monty; McFarland, Mark L.; Lesikar, Bruce J.
water and wasted embodied energy. While 5% of California'senergy intensive (94). Water- inefficient fixtures and fittings (toilets, showerheads, urinals, faucets) represent both wasted
using virtual water (e.g. coffee produced in an environmentis produced in an environment in which it takes less water
Large Industrial Renewable Energy Purchase Program (New Brunswick) |
Large Industrial Renewable Energy Purchase Program (New Brunswick) Large Industrial Renewable Energy Purchase Program (New Brunswick) Large Industrial Renewable Energy Purchase Program (New Brunswick) < Back Eligibility Agricultural Commercial Developer Industrial Investor-Owned Utility Local Government Municipal/Public Utility Rural Electric Cooperative Tribal Government Utility Savings Category Buying & Making Electricity Water Home Weatherization Solar Wind Program Info State New Jersey Program Type Performance-Based Incentive Provider New Brunswick Energy and Mines Beginning January 1, 2012 the Large Industrial Renewable Energy Purchase Program allows NB Power to purchase renewable energy generated by its largest customers at a rate of $95/MWh. This renewable energy will count towards meeting the Province's renewable energy targets at a purchase
Water Induced Surface Reconstruction of the Oxygen (2x1) covered Ru(0001)
Low temperature scanning tunneling microscopy (STM) and density functional theory (DFT) were used to study the adsorption of water on a Ru(0001) surface covered with half monolayer of oxygen. The oxygen atoms occupy hcp sites in an ordered structure with (2x1) periodicity. DFT predicts that water is weakly bound to the unmodified surface, 86 meV compared to the ~;;200 meV water-water H-bond. Instead, we found that water adsorption causes a shift of half of the oxygen atoms from hcp sites to fcc sites, creating a honeycomb structure where water molecules bind strongly to the exposed Ru atoms. The energy cost of reconstructing the oxygen overlayer, around 230 meV per displaced oxygen atom, is more than compensated by the larger adsorption energy of water on the newly exposed Ru atoms. Water forms hydrogen bonds with the fcc O atoms in a (4x2) superstructure due to alternating orientations of the molecules. Heating to 185 K results in the complete desorption of the water layer, leaving behind the oxygen honeycomb structure, which is metastable relative to the original (2x1). This stable structure is not recovered until after heating to temperatures close to 260K.
Maier, Sabine; Cabrera-Sanfelix, Pepa; Stass, Ingeborg; Sanchez-Portal, Daniel; Arnau, Andres; Salmeron, Miquel
A theoretical investigation of ferromagnetic tunnel junctions with 4-valued conductances
In considering a novel function in ferromagnetic tunnel junctions consisting of ferromagnet(FM)/barrier/FM junctions, we theoretically investigate multiple valued (or multi-level) cell property, which is in principle realized by sensing conductances of four states recorded with magnetization configurations of two FMs; that is, (up,up), (up,down), (down,up), (down,down). To obtain such 4-valued conductances, we propose FM1/spin-polarized barrier/FM2 junctions, where the FM1 and FM2 are different ferromagnets, and the barrier has spin dependence. The proposed idea is applied to the case of the barrier having localized spins. Assuming that all the localized spins are pinned parallel to magnetization axes of the FM1 and FM2, 4-valued conductances are explicitly obtained for the case of many localized spins. Furthermore, objectives for an ideal spin-polarized barrier are discussed.
Satoshi Kokado; Kikuo Harigaya
Tunneling of Massive Dirac Fermions in Graphene through Time-periodic Potential
The energy spectrum of graphene sheet with a single barrier structure having a time periodic oscillating height and subjected to magnetic field is analyzed. The corresponding transmission is studied as function of the obtained energy and the potential parameters. Quantum interference within the oscillating barrier has an important effect on quasiparticles tunneling. In particular the time-periodic electromagnetic field generates additional sidebands at energies \\epsilon + l\\hbar \\omega (l=0,\\pm 1, \\cdots) in the transmission probability originating from the photon absorption or emission within the oscillating barrier. Due to numerical difficulties in truncating the resulting coupled channel equations we limited ourselves to low quantum channels, i.e. l=0,\\pm 1.
Ahmed Jellal; Miloud Mekkaoui; El Bouazzaoui Choubabi; Hocine Bahlouli
Scanning tunneling microscopy reveals LiMnAs is a room temperature anti-ferromagnetic semiconductor
We performed scanning tunneling microscopy and spectroscopy on a LiMnAs(001) thin film epitaxially grown on an InAs(001) substrate by molecular beam epitaxy. While the in situ cleavage exposed only the InAs(110) non-polar planes, the cleavage continued into the LiMnAs thin layer across several facets. We combined both topography and current mappings to confirm that the facets correspond to LiMnAs. By spectroscopy we show that LiMnAs has a band gap. The band gap evidenced in this study, combined with the known Neel temperature well above room temperature, confirms that LiMnAs is a promising candidate for exploring the concepts of high temperature semiconductor spintronics based on antiferromagnets.
Wijnheijmer, A. P.; Koenraad, P. M. [COBRA Inter-University Research Institute, Department of Applied Physics, Eindhoven University of Technology, P. O. Box 513, NL-5600 MB Eindhoven (Netherlands); Marti, X. [Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 121 16 Prague 2 (Czech Republic); Institute of Physics ASCR, v.v.i., Cukrovarnicka 10, 162 53 Prague 6 (Czech Republic); Holy, V. [Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 121 16 Prague 2 (Czech Republic); Cukr, M.; Novak, V. [Institute of Physics ASCR, v.v.i., Cukrovarnicka 10, 162 53 Prague 6 (Czech Republic); Jungwirth, T. [Institute of Physics ASCR, v.v.i., Cukrovarnicka 10, 162 53 Prague 6 (Czech Republic); School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom)
Magnetism of Semiconductor-Based Magnetic Tunnel Junctions under Electric Field from First Principles
Semiconductor magnetic tunnel junctions (MTJs), composed of diluted magnetic semiconductors (DMSs) sandwiching a semiconductor barrier, have potential applications in spintronics but their development has been slow due to the difficulty of controlling the magnetism of DMSs. In terms of density functional calculations for model semiconductor MTJs, (Zn,Co)O/ZnO/(Zn,Co)O and (Ga,Mn)N/GaN/(Ga,Mn)N, we show that the magnetic coupling between the transition metal ions in each DMS electrode of such semiconductor MTJs can be switched from ferromagnetic to antiferromagnetic, or vice versa, under the application of external electric field across the junctions. Our results suggest a possible avenue for the application of semiconductor MTJs.
Kan, E.; Xiang, H.; Yang, J.; Whangbo, M. H.
Tunneling and transmission resonances of a Dirac particle by a double barrier
We calculate the tunneling process of a Dirac particle across two square barriers separated a distance $d$, as well as the scattering by a double cusp barrier where the centers of the cusps are separated a distance larger than their screening lengths. Using the scattering matrix formalism, we obtain the transmission and reflection amplitudes for the scattering processes of both configurations. We show that, the presence of transmission resonances modifies the Lorentizian shape of the energy resonances and induces the appearance of additional maxima in the transmission coefficient in the range of energies where transmission resonances occur. We calculate the Wigner time-delay and show how their maxima depend on the position of the transmission resonance.
Victor M. Villalba; Luis Gonzalez-Arraga
Applied Bias Slewing in Transient Wigner Function Simulation of Resonant Tunneling Diodes
The Wigner function formulation of quantum mechanics has shown much promise as a basis for accurately modeling quantum electronic devices, especially under transient conditions. In this work, we demonstrate the importance of using a finite applied bias slew rate (as opposed to instantaneous switching) to better approximate experimental device conditions, and thus to produce more accurate transient Wigner function simulation results. We show that the use of instantaneous (and thus unphysical) switching can significantly impact simulation results and lead to incorrect conclusions about device operation. We also find that slewed switching can reduce the high computational demands of transient simulations. The resonant tunneling diode (RTD) is used as a test device, and simulation results are produced with SQUADS (Stanford QUAntum Device Simulator). I. INTRODUCTION T HE WIGNER function formulation of quantum mechanics has proven to be a very effective basis for the numerical simulation ...
Bryan A. Biegel; Student Member; James D. Plummer
Tunneling of a Massless Field through a 3D Gaussian Barrier
We propose a method for the approximate computation of the Green function of a scalar massless field Phi subjected to potential barriers of given size and shape in spacetime. This technique is applied to the case of a 3D gaussian ellipsoid-like barrier, placed on the axis between two pointlike sources of the field. Instead of the Green function we compute its temporal integral, that gives the static potential energy of the interaction of the two sources. Such interaction takes place in part by tunneling of the quanta of Phi across the barrier. We evaluate numerically the correction to the potential in dependence on the size of the barrier and on the barrier-sources distance.
G. Modanese
Symbolic-numerical Algorithm for Generating Cluster Eigenfunctions: Tunneling of Clusters Through Repulsive Barriers
A model for quantum tunnelling of a cluster comprising A identical particles, coupled by oscillator-type potential, through short-range repulsive potential barriers is introduced for the first time in the new symmetrized-coordinate representation and studied within the s-wave approximation. The symbolic-numerical algorithms for calculating the effective potentials of the close-coupling equations in terms of the cluster wave functions and the energy of the barrier quasistationary states are formulated and implemented using the Maple computer algebra system. The effect of quantum transparency, manifesting itself in nonmonotonic resonance-type dependence of the transmission coefficient upon the energy of the particles, the number of the particles A=2,3,4, and their symmetry type, is analyzed. It is shown that the resonance behavior of the total transmission coefficient is due to the existence of barrier quasistationary states imbedded in the continuum.
Vinitsky, Sergue; Chuluunbaatar, Ochbadrakh; Rostovtsev, Vitaly; Hai, Luong Le; Derbov, Vladimir; Krassovitskiy, Pavel
Coherent destruction of tunneling in a lattice array under selective in-phase modulations
We explore the coherent destruction of tunneling (CDT) in a lattice array under selective in-phase harmonic modulations, in which some selected lattice sites are driven by in-phase harmonic oscillating fields and other lattice sites are undriven. Due to the occurrence of CDT, if the driving amplitude A and the driving frequency {omega} are tuned to satisfy the zeroth-order Bessel function J{sub 0}(A/{omega})=0, the driven lattice sites are approximately decoupled from the undriven lattice sites. The CDT even takes place in lattice systems with high-order couplings between non-nearest-neighbor lattice sites. By using the CDT induced by selective in-phase harmonic modulations, we propose a scheme for realizing directed transport of a single particle. It is possible to observe the CDT in an engineered optical waveguide array, which provides an opportunity for controlling light propagation and designing switchlike couplers.
Luo, Xiaobing [Department of Physics, Jinggangshan University, Ji'an 343009 (China); State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-Sen University, Guangzhou 510275 (China); Huang, Jiahao; Lee, Chaohong [State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-Sen University, Guangzhou 510275 (China)
Hydrogen adsorption on Ru(001) studied by Scanning TunnelingMicroscopy
The adsorption of hydrogen on Ru(001) was studied by scanning tunneling microscopy at temperatures around 50 K. Hydrogen was found to adsorb dissociatively forming different ordered structures as a function of coverage. In order of increasing coverage {theta} in monolayers (ML) these were ({radical}3 x {radical}3)r30{sup o} at {theta} = 0.3 ML; (2 x 1) at {theta} = 0.50 ML, (2 x 2)-3H at {theta} = 0.75, and (1 x 1) at {theta} = 1.00. Some of these structures were observed to coexist at intermediate coverage values. Close to saturation of 1 ML, H-vacancies (unoccupied three fold fcc hollow Ru sites) were observed either as single entities or forming transient aggregations. These vacancies diffuse and aggregate to form active sites for the dissociative adsorption of hydrogen.
Tatarkhanov, Mous; Rose, Franck; Fomin, Evgeny; Ogletree, D.Frank; Salmeron, Miquel
Method and apparatus for differential spectroscopic atomic-imaging using scanning tunneling microscopy
A Method and apparatus for differential spectroscopic atomic-imaging is disclosed for spatial resolution and imaging for display not only individual atoms on a sample surface, but also bonding and the specific atomic species in such bond. The apparatus includes a scanning tunneling microscope (STM) that is modified to include photon biasing, preferably a tuneable laser, modulating electronic surface biasing for the sample, and temperature biasing, preferably a vibration-free refrigerated sample mounting stage. Computer control and data processing and visual display components are also included. The method includes modulating the electronic bias voltage with and without selected photon wavelengths and frequency biasing under a stabilizing (usually cold) bias temperature to detect bonding and specific atomic species in the bonds as the STM rasters the sample. This data is processed along with atomic spatial topography data obtained from the STM raster scan to create a real-time visual image of the atoms on the sample surface.
Kazmerski, Lawrence L. (Lakewood, CO)
Development of a Digital Controller for a Vertical Wind Tunnel (VWT) Prototype to Mitigate Ball Fluctuations
The objective of this research was to mitigate fluctuations of a levitated ping pong ball within a vertical wind tunnel (VWT) prototype. This was made possible by remodeling the VWT system with its inherent nonlinear characteristics instead of assuming constant parameter relationships. By considering these nonlinearities a more accurate model was developed that better represented the actual system. The gain scheduling controller technique was chosen to control the ball's vertical displacement within VWT prototype. After remodeling the VWT's dynamics, the transfer function gain, for three different specified equilibrium points, were found to be within ±35% of the original system dynamics' gain which explain why ball fluctuation was present. Also, three different controllers were developed to mitigate fluctuations at 0.10m, 0.15m and 0.20m. The three controllers were combined to create the gain scheduled controller; however, no testing has been done due to sudden, last minute hardware malfunction.
Silva, Ramon A.
Water-heating dehumidifier
A water-heating dehumidifier includes a refrigerant loop including a compressor, at least one condenser, an expansion device and an evaporator including an evaporator fan. The condenser includes a water inlet and a water outlet for flowing water therethrough or proximate thereto, or is affixed to the tank or immersed into the tank to effect water heating without flowing water. The immersed condenser design includes a self-insulated capillary tube expansion device for simplicity and high efficiency. In a water heating mode air is drawn by the evaporator fan across the evaporator to produce cooled and dehumidified air and heat taken from the air is absorbed by the refrigerant at the evaporator and is pumped to the condenser, where water is heated. When the tank of water heater is full of hot water or a humidistat set point is reached, the water-heating dehumidifier can switch to run as a dehumidifier.
Tomlinson, John J. (Knoxville, TN)
Residential water heating is a large source of energy use in California homes. This project took a life cycle approach to comparing tank and tankless water heaters in Northern and Southern California. Information about the life cycle phases was calculated using the European Union?s Methodology study for EcoDesign of Energy-using Products (MEEUP) and the National Renewable Energy Laboratory?s Life Cycle Inventory (NREL LCI) database. In a unit-to-unit comparison, it was found that tankless water heaters would lessen impacts of water heating by reducing annual energy use by 2800 MJ/year (16% compared to tank), and reducing global warming emissions by 175 kg CO2 eqv./year (18% reduction). Overall, the production and combustion of natural gas in the use phase had the largest impact. Total waste, VOCs, PAHs, particulate matter, and heavy-metals-to-air categories were also affected relatively strongly by manufacturing processes. It was estimated that tankless water heater users would have to use 10 more gallons of hot water a day (an increased usage of approximately 20%) to have the same impact as tank water heaters. The project results suggest that if a higher percentage of Californians used tankless water heaters, environmental impacts caused by water heating would be smaller.
Lu, Alison; McMahon, James; Masanet, Eric; Lutz, Jim
Research Addressing Power Plant Water
Addressing Power Plant Water Management to Minimize Water Use while Providing Reliable Electricity Generation Water and Energy 2 Water and Energy are inextricably linked. Because...
A Wind Tunnel Study on the Shape, Oscillation, and Internal Circulation of Large Raindrops with Sizes between 2.5 and 7.5 mm
Precipitation prediction using weather radars requires detailed knowledge of the shape parameters of raindrops falling at their terminal velocities in air. Because the raindrops undergo oscillation, the most important shape parameters from the ...
Miklós Szakáll; Karoline Diehl; Subir K. Mitra; Stephan Borrmann
Impact of temperature increments on tunneling barrier height and effective electron mass for plasma nitrided thin SiO{sub 2} layer on a large wafer area
Thermally grown SiO{sub 2} layers were treated by a plasma nitridation process realized in a vertical furnace. The combination of a pulsed-low frequency plasma and a microwave remote plasma with N{sub 2}/NH{sub 3}/He feed gas mixture was used to nitride the thermally grown SiO{sub 2} gate dielectrics of MIS structures. Temperature dependency of effective masses and the barrier heights for electrons in pure thermally grown SiO{sub 2} as well as plasma nitrided SiO{sub 2} in high electric field by means of Fowler-Nordheim regime was determined. It is frequently seen from the literature that either effective electron mass or barrier height (generally effective electron mass) is assumed to be a constant and, as a result, the second parameter is calculated under the chosen assumption. However, in contrast to general attitude of previous studies, this work does not make any such assumptions for the calculation of neither of these two important parameters of an oxide at temperature ranges from 23 to 110 deg. C for SiO{sub 2}, and 23 to 130 deg. C for nitrided oxide. It is also shown here that both parameters are affected from the temperature changes; respectively, the barrier height decreases while the effective mass increases as a result of elevated temperature in both pure SiO{sub 2} and plasma nitrided SiO{sub 2}. Therefore, one parameter could be miscalculated if the other parameter, i.e., effective mass of electron, was assumed to be a constant with respect to variable physical conditions like changing temperature. Additionally, the barrier heights were calculated just by taking constant effective masses for both types of oxides to be able to compare our results to common literature values.
Aygun, G. [Fraunhofer IISB, Schottkystrasse 10, 91058 Erlangen (Germany); Department of Physics, Izmir Institute of Technology, TR-35430 Urla, Izmir (Turkey); Roeder, G.; Erlbacher, T.; Wolf, M.; Schellenberger, M.; Pfitzner, L. [Fraunhofer IISB, Schottkystrasse 10, 91058 Erlangen (Germany)
Solar Hot Water Resources and Technologies | Department of Energy
Solar Hot Water Resources and Technologies Solar Hot Water Resources and Technologies Solar Hot Water Resources and Technologies October 7, 2013 - 11:49am Addthis Photo of a standalone solar hot water system standing in front of a clothesline with a backdrop of evergreen trees. This solar hot