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|Application number
|Publication date
|Sep 6, 2011
|Filing date
|Apr 19, 2010
|Priority date
|Nov 17, 2004
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|Avetik Harutyunyan, Toshio Tokune, Elena Mora Fernandez
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|Honda Motor Co., Ltd.
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|Patent Citations (4), Non-Patent Citations (9), Referenced by (3), Classifications (14), Legal Events (1)
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This application is a divisional of U.S. application Ser. No. 10/992,275 filed on Nov. 17, 2004, which is incorporated by reference herein in its entirety.
The present invention relates to methods for the preparation (synthesis) of carbon single-walled nanotubes using chemical vapor deposition methods.
Carbon nanotubes are hexagonal networks of carbon atoms forming seamless tubes with each end capped with half of a fullerene molecule. They were first reported in 1991 by Sumio Iijima who produced multi-layer concentric tubes or multi-walled carbon nanotubes by evaporating carbon in an arc discharge. They reported carbon nanotubes having up to seven walls. In 1993, Iijima's group and an IBM team headed by Donald Bethune independently discovered that a single-wall nanotube could be made by vaporizing carbon together with a transition metal such as iron or cobalt in an arc generator (see Iijima et al. Nature 363:603 (1993); Bethune et al., Nature 363: 605 (1993) and U.S. Pat. No. 5,424,054). The original syntheses produced low yields of non-uniform nanotubes mixed with large amounts of soot and metal particles.
Presently, there are three main approaches for the synthesis of single- and multi-walled carbon nanotubes. These include the electric arc discharge of graphite rod (Journet et al. Nature 388: 756 (1997)), the laser ablation of carbon (Thess et al. Science 273: 483 (1996)), and the chemical vapor deposition of hydrocarbons (Ivanov et al. Chem. Phys. Lett 223: 329 (1994); Li et al. Science 274: 1701 (1996)). Multi-walled carbon nanotubes can be produced on a commercial scale by catalytic hydrocarbon cracking while single-walled carbon nanotubes are still produced on a gram scale.
Generally, single-walled carbon nanotubes are preferred over multi-walled carbon nanotubes because they have unique mechanical and electronic properties. Defects are less likely to occur in single-walled carbon nanotubes because multi-walled carbon nanotubes can survive occasional defects by forming bridges between unsaturated carbon valances, while single-walled carbon nanotubes have no neighboring walls to compensate for defects. Defect-free single-walled nanotubes are expected to have remarkable mechanical, electronic and magnetic properties that could be tunable by varying the diameter, number of concentric shells, and chirality of the tube.
It is generally recognized that smaller catalyst particles of less than 3 nm are preferred for the growth of smaller diameter carbon nanotubes. However, the smaller catalyst particles easily aggregate at the higher temperatures required for the synthesis of carbon nanotubes. U.S. Patent Application No. 2004/0005269 to Huang et al. discloses a mixture of catalysts containing at least one element from Fe, Co, and Ni, and at least one supporting element from the lanthanides. The lanthanides are said to decrease the melting point of the catalyst by forming alloys so that the carbon nanostructures can be grown at lower temperatures.
Aside from the size of the catalyst, the temperature of the reaction chamber can also be important for the growth of carbon nanotubes. U.S. Pat. No. 6,764,874 to Zhang et al. discloses a method of preparing nanotubes by melting aluminum to form an alumina support and melting a thin nickel film to form nickel nanoparticles on the alumina support. The catalyst is then used in a reaction chamber at less than 850� C. U.S. Pat. No. 6,401,526, and U.S. Patent Application Publication No. 2002/00178846, both to Dai et al., disclose a method of forming nanotubes for atomic force microscopy. A portion of the support structure is coated with a liquid phase precursor material that contains a metal-containing salt and a long-chain molecular compound dissolved in a solvent. The carbon nanotubes are made at a temperature of 850� C.
It is well known that the diameter of the single-walled nanotubes (SWNTs) produced is proportional to the size of the catalyst particle. In order to synthesize nanotubes of small diameter, it is necessary to have catalyst particles of small particle size (less than about 1 nm). Catalysts of small average particle sizes with narrow distribution are difficult to synthesize. Further, recognized methods for determining the catalyst particle size distribution are not currently available, especially when the catalyst particles are supported on support powders, and thus buried inside the pores of the support powders.
Thus, there is a need for methods and processes for controllable synthesis of carbon single-walled nanotubes with small and narrow distributed diameters. Accordingly, the present invention provides novel methods and processes for determining the average particle size and particle size distribution of catalyst particles that can be used for preparation and optimization of catalyst and for the synthesis of SWNTs with small and narrow distributed diameters.
The present invention provides methods and processes for determining the size of the catalyst particles, and/or for determining the size of the catalyst particles on support materials. The catalyst particles can be used in methods and processes for growing single-wall carbon nanotubes in high yields and with high quality.
The present invention provides methods for determining the average particle size of a metal catalyst by obtaining magnetization curve of the metal catalyst using SQUID and determining the average particle size from the magnetization curve. The metal catalyst can be a Group V metal, a Group VI metal, a Group VII metal, a Group VIII metal, a lanthanide, or a transition metal or combinations thereof. The catalyst preferably has a particle size between about 0.1 nm to about 10 nm. The catalyst can be supported on a powdered oxide, such as Al2O3, SiO2, MgO and the like, herein the catalyst and the support are in a ratio of about 1:1 to about 1:50.
In another aspect, the methods involve contacting a carbon precursor gas with a catalyst on a support, wherein the catalyst has an average diameter of less than about 2 nm and wherein SWNT having narrow distribution of diameters are formed. The average particle size of a metal catalyst by obtaining magnetization curve of the metal catalyst using SQUID and determining the average particle size from the magnetization curve. The carbon precursor gas can be methane that can additionally contain other gases such as argon and hydrogen. The catalyst can be a Group V metal, a Group VI metal, a Group VII metal, a Group VIII metal, a lanthanide, or a transition metal or combinations thereof. The catalyst preferably has a particle size between about 1 nm to about 50 nm. The catalyst can be supported on a powdered oxide, such as Al2O3, SiO2, MgO and the like, where the catalyst and the support are in a ratio of about 1:1 to about 1:50. Once the desired particle size of the catalyst is obtained, as determined by SQUID, they can be used for the production of SWNTs of high quality.
In another aspect, the invention provides a carbon nanotube structure produced by the process of contacting a carbon precursor gas with a catalyst on a support at a temperature between the melting point of the catalyst and the eutectic point of the catalyst and carbon. The carbon precursor gas can be methane that can additionally contain other gases such as argon and hydrogen. The catalyst can be a V metal, a Group VI metal, a Group VII metal, a Group VIII metal, a lanthanide, or a transition metal or combinations thereof. The catalyst preferably has a particle size between about 1 nm to about 15 nm. The catalyst can be supported on a powdered oxide, such as Al2O3, SiO2, MgO and the like, herein the catalyst and the support are in a ratio of about 1:1 to about 1:50.
Unless otherwise stated, the following terms used in this application, including the specification and claims, have the definitions given below. It must be noted that, as used in the specification and the appended claims, the singular forms "a," "an" and "the" include plural referents unless the context clearly dictates otherwise. Definition of standard chemistry terms may be found in reference works, including Carey and Sundberg (1992) "Advanced Organic Chemistry 3rd Ed." Vols. A and B, Plenum Press, New York, and Cotton et al. (1999) "Advanced Inorganic Chemistry 6th Ed." Wiley, New York.
The term "magnetic," as used hereinafter, includes all types of materials that respond to magnetic fields, such as, but not limited to, ferromagnetic, paramagnetic, and superparamagnetic materials.
The term "magnetic material" encompasses any material having at least some magnetic content and therefore includes material having an amount of magnetic material ranging from greater than 0% to 100%.
The term "ferromagnetic" as used herein refers to substances such as iron, nickel, or cobalt and various alloys that exhibit extremely high magnetic permeability, a characteristic saturation point, and magnetic hysteresis.
The term "paramagnetic" refers to a material having unpaired electron in the atoms of the material whose induced magnetization is parallel and proportional to the strength of the intensity of the magnetizing field.
The term "superparamagnetic" refers to particles with the size below which the anisotropy energy is smaller than the thermal energy. In that case, thermal fluctuations cause the magnetic moment of the domains to fluctuate randomly between their energy minima.
The terms "single-walled carbon nanotube" or "one-dimensional carbon nanotube" are used interchangeable and refer to cylindrically shaped thin sheet of carbon atoms having a wall consisting essentially of a single layer of carbon atoms, and arranged in a hexagonal crystalline structure with a graphitic type of bonding.
The term "multi-walled carbon nanotube" as used herein refers to a nanotube composed of more than one concentric tubes.
The terms "metalorganic" or "organometallic" are used interchangeably and refer to co-ordination compounds of organic compounds and a metal, a transition metal or metal halide.
The present invention discloses methods, and processes for determining the size of the catalyst particles, thereby allowing for the control of the quality of the catalyst. The catalysts thus produced can be used in the manufacture of carbon single-wall nanotubes (SWNT) and structures using the carbon vapor deposition method. The catalyst produced by the inventive methods provides high yield and high quality of carbon SWNTs.
The invention provides methods and processes for determining the size distribution of particles, particularly metal catalysts on support material. According to the invention, SWNT of preselected diameter distribution can be produced by contacting a carbon-containing gas with a catalyst supported on a support. The catalyst particles are synthesized to have a narrow range of diameter. The diameter of the catalyst particles, with or without support, can be evaluated by using SQUID magnetometer, and the catalyst synthesis process (variation of metal/support ratio) can be continued until catalyst particles having a narrow range of diameters are obtained. The catalyst thus obtained can be contacted with a carbon-containing gas at a temperature sufficient to decompose the carbon-containing gas and causes the growth of SWNT. Thus, the diameter distribution of the SWNTs can be controlled by using catalyst particles having a narrow range of diameters.
The catalyst composition can be any catalyst composition known to those of skill in the art. The catalyst particles themselves can be of any material that exhibits ferri- or ferromagnetism. Conveniently, the particles will be of a magnetic metal or alloy, such as, for example, iron, iron oxide, or a ferrite such as cobalt, nickel, chromium, yttrium, hafnium or manganese. The particles useful according to the invention will preferably have an average overall particle size of up to 50 nm to about 1 μm, although, in general, the particle sizes for individual particles can be from about 400 nm to about 1 μm. The catalyst particles are preferably at least single domain size, generally less than about 2 nm.
The function of the catalyst when used in the carbon nanotube growth process is to decompose the carbon precursors and aid the deposition of ordered carbon. The methods and processes of the present invention preferably use metal nanoparticles as the metallic catalyst. The metal or combination of metals selected as the catalyst can be processed to obtain the desired particle size and diameter distribution. The metal nanoparticles can then be separated by being supported on a material suitable for use as a support during synthesis of carbon nanotubes using the metal growth catalysts described below. The particle size of the catalyst particle, before and after being supported, can be determined using superconducting quantum interference device (SQUID) magnetometer. As known in the art, the support can be used to separate the catalyst particles from each other thereby providing the catalyst materials with greater surface area in the catalyst composition. Such support materials include powders of crystalline silicon, polysilicon, silicon nitride, tungsten, magnesium, aluminum and their oxides, preferably aluminum oxide, silicon oxide, magnesium oxide, or titanium dioxide, or combination thereof, optionally modified by addition elements, are used as support powders. Silica, alumina and other materials known in the art may be used as support, preferably alumina is used as the support.
The metal catalyst can be selected from a Group V metal, such as V or Nb, and mixtures thereof, a Group VI metal including Cr, W, or Mo, and mixtures thereof, VII metal, such as, Mn, or Re, Group VIII metal including Co, Ni, Ru, Rh, Pd, Os, Ir, Pt, and mixtures thereof, or the lanthanides, such as Ce, Eu, Er, or Yb and mixtures thereof, or transition metals such as Cu, Ag, Au, Zn, Cd, Sc, Y, or La and mixtures thereof. Specific examples of mixture of catalysts, such as bimetallic catalysts, which may be employed by the present invention include Co—Cr, Co—W, Co—Mo, Ni—Cr, Ni—W, Ni—Mo, Ru—Cr, Ru—W, Ru—Mo, Rh—Cr, Rh—W, Rh—Mo, Pd—Cr, Pd—W, Pd—Mo, Ir—Cr, Pt—Cr, Pt—W, and Pt—Mo. Preferably, the metal catalyst is iron, cobalt, nickel, molybdeum, or a mixture thereof, such as Fe—Mo, Co—Mo and Ni—Fe—Mo.
The metal, bimetal, or combination of metals are used to prepare metal nanoparticles having defined particle size and diameter distribution. The metal nanoparticles can be prepared using the literature procedure described in Harutyunyan et al., NanoLetters 2, 525 (2002). Alternatively, the catalyst nanoparticles can be prepared by thermal decomposition of the corresponding metal salt added to a passivating salt, and the temperature of the solvent adjusted to provide the metal nanoparticles, as described in the co-pending and co-owned U.S. patent application Ser. No. 10/304,316, or by any other method known in the art. The particle size and diameter of the metal nanoparticles can be controlled by using the appropriate concentration of metal in the passivating solvent and by controlling the length of time the reaction is allowed to proceed at the thermal decomposition temperature. The metal salt can be any salt of the metal, and can be selected such that the melting point of the metal salt is lower than the boiling point of the passivating solvent. Thus, the metal salt contains the metal ion and a counter ion, where the counter ion can be nitrate, nitride, perchlorate, sulfate, sulfide, acetate, halide, oxide, such as methoxide or ethoxide, acetylacetonate, and the like. For example, the metal salt can be iron acetate (FeAc2), nickel acetate (NiAc2), palladium acetate (PdAc2), molybdenum acetate (MoAc3), and the like, and combinations thereof. The melting point of the metal salt is preferably about 5� C. to 50� C. lower than the boiling point, more preferably about 5� C. to about 20� C. lower than the boiling point of the passivating solvent. The solvent can be an ether, such as a glycol ether, 2-(2-butoxyethoxy)ethanol, H(OCH2CH2)2—O—(CH2)3CH3, which will be referred to below using the common name dietheylene glycol mono-n-butyl ether, and the like.
Metal nanoparticles having an average particle size of about 0.01 nm to about 20 nm, more preferably about 0.1 nm to about 3 nm and most preferably about 0.3 nm to 2 nm can be prepared. The metal nanoparticles can thus have a particle size of 0.1, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 nm, and up to about 20 nm. In another aspect, the metal nanoparticles can have a range of particle size, or diameter distribution. For example, the metal nanoparticles can have particle sizes in the range of about 0.1 nm and about 5 nm in size, about 3 nm and about 7 nm in size, or about 5 nm and about 11 nm in size.
The size and distribution of metal nanoparticles produced can be verified by any suitable method. One method of verification is transmission electron microscopy (TEM). A suitable model is the Phillips CM300 FEG TEM that is commercially available from FEI Company of Hillsboro, Oreg. In order to take TEM micrographs of the metal nanoparticles, 1 or more drops of the metal nanoparticle/passivating solvent solution are placed on a carbon membrane grid or other grid suitable for obtaining TEM micrographs. The TEM apparatus is then used to obtain micrographs of the nanoparticles that can be used to determine the distribution of nanoparticle sizes created.
In another method, the size of the nanoparticles and their distribution can be determined using SQUID. SQUID magnetometers are commercially available from companies such as Biomagnetic Technologies Inc., San Diego, Calif. and Siemens AG of Germany, and include both single and multichannel devices that are capable of detecting magnetic fields at plurality of locations simultaneously. SQUID magnetometers generally comprise a superconducting pick up coil system and a detector system (the SQUID) which itself comprises one or two Josephson junctions inserted into a loop of superconducting wire. The magnetic flux within such loops is quantized and changes in the magnetic field experienced by the pick up coils cause a measurable change in the current flowing through the detector. The SQUID magnetometers are capable of measuring very low magnetic fields, for example, as low as 10−14 Tesla. The technique thus finds use in a variety of fields.
The magnetic properties of the catalyst particles, either beginning of the synthesis process or at the end of the process, can be measured using SQUID. The details of the operation of SQUID are known to those skilled in the art, and can be found in C. Hilbert and J. Clarke, Journal of Low Temperature Physics 61, 237 and 261 (1985). The signals involved in detecting the electric induction phenomenon of the present invention can be small. Hence, the reduction in the noise level in the system can be advantageous, and can be achieved by optionally conducting the measurements at reduced temperature, such as in a liquid helium environment to reduce thermally induced noise levels.
It has been found that the magnetization curves for catalysts having particle sizes of less than about 1.5 nm is paramagnetic, and the magnetization curves for particle sizes greater than about 2 nm is superparamagnetic, and greater than 4 nm is ferromagnetic. Thus, in one aspect, the evolution of magnetic properties of the catalyst particles can be used for synthesis of the catalyst particles with the desired sized. The metal/support material molar ratio can be varied if the magnetization curves observed in SQUID are not the same as the magnetization curves expected for the desired particle sizes. The ratio can be fixed if the magnetization curves observed in SQUID are similar to the magnetization curves expected for the desired particle sizes.
Thus, if the desired average particle size is about 2 nm or greater, such as between 1 nm and about 3 nm, then the variation of the metal/support material ratio is continued until the SQUID measurements provide magnetization curves indicating that the particles are superparamagnetic. If the desired average particle size is less than about 1 nm, such as 0.5 nm, 0.8 nm, 1 nm, and the like, then the variation of the metal/support material ratio is continued until the SQUID measurements provide magnetization curves indicating that the particles are paramagnetic.
The metal nanoparticles, such as those formed by thermal decomposition described in detail above, and, optionally characterized by SQUID, can then be supported on solid supports. The solid support can be silica, alumina, MCM-41, MgO, ZrO2, aluminum-stabilized magnesium oxide, zeolites, or other oxidic supports known in the art, and combinations thereof. For example, Al2O3—SiO2 hybrid support could be used. Preferably, the support is aluminum oxide (Al2O3) or silica (SiO2). The oxide used as solid support can be powdered thereby providing small particle sizes and large surface areas. The powdered oxide can preferably have a particle size between about 0.01 μm to about 100 μm, more preferably about 0.1 μm to about 10 μm, even more preferably about 0.5 μm to about 5 μm, and most preferably about 1 μm to about 2 μm. The powdered oxide can have a surface area of about 50 to about 1000 m2/g, more preferably a surface area of about 200 to about 800 m2/g. The powdered oxide can be freshly prepared or commercially available.
In one aspect, the metal nanoparticles are supported on solid supports via secondary dispersion and extraction. Secondary dispersion begins by introducing particles of a powdered oxide, such as aluminum oxide (Al2O3) or silica (SiO2), into the reaction vessel after the thermal decomposition reaction. A suitable Al2O3 powder with 1-2 μm particle size and having a surface area of 300-500 m2/g is commercially available from Alfa Aesar of Ward Hill, Mass., or Degussa, N.J. Powdered oxide can be added to achieve a desired weight ratio between the powdered oxide and the initial amount of metal used to form the metal nanoparticles. Typically, the weight ratio can be between about 10:1 and about 15:1. For example, if 100 mg of iron acetate is used as the starting material, then about 320 to 480 mg of powdered oxide can be introduced into the solution. The weight ratio of metal nanoparticles to powdered oxide can be between about 1:10 and 1:15, such as, for example, 1:11, 1:12, 2:25, 3:37, 1:13, 1:14, and the like.
As will be apparent to those of skill in the art, the catalyst thus prepared can be stored for later use. In another aspect, the metal nanoparticles can be previously prepared, isolated from the passivating solvent, and purified, and then added to a powdered oxide in a suitable volume of the same or different passivating solvent. The metal nanoparticles and powdered oxide can be homogenously dispersed, extracted from the passivating solvent, and processed to increase the effective surface area as described above. Other methods for preparing the metal nanoparticle and powdered oxide mixture will be apparent to those skilled in the art.
Three different groups of iron catalysts supported on alumina were prepared and their magnetization curves obtained using SQUID, are shown in
The metal nanoparticles thus formed can be used as a growth catalyst for synthesis of carbon nanotubes, nanofibers, and other one-dimensional carbon nanostructures by a chemical vapor deposition (CVD) process.
The carbon nanotubes can be synthesized using carbon precursors, such as carbon containing gases. In general, any carbon containing gas that does not pyrolize at temperatures up to 800� C. to 1000� C. can be used. Examples of suitable carbon-containing gases include carbon monoxide, aliphatic hydrocarbons, both saturated and unsaturated, such as methane, ethane, propane, butane, pentane, hexane, ethylene, acetylene and propylene; oxygenated hydrocarbons such as acetone, and methanol; aromatic hydrocarbons such as benzene, toluene, and naphthalene; and mixtures of the above, for example carbon monoxide and methane. In general, the use of acetylene promotes formation of multi-walled carbon nanotubes, while CO and methane are preferred feed gases for formation of single-walled carbon nanotubes. The carbon-containing gas may optionally be mixed with a diluent gas such as hydrogen, helium, argon, neon, krypton and xenon or a mixture thereof.
The methods and processes of the invention provide for the synthesis of SWNTs with a narrow distribution of diameters. The narrow distribution of carbon nanotube diameters is obtained by activating small diameter catalyst particles preferentially during synthesis by selecting the lowest eutectic point as the reaction temperature.
In one aspect of the invention, the metal nanoparticles supported on powdered oxides can be contacted with the carbon source at the reaction temperatures according to the literature methods described in Harutyunyan et al., NanoLetters 2, 525 (2002). Alternatively, the metal nanoparticles supported on the oxide powder can be aerosolized and introduced into the reactor maintained at the reaction temperature. Simultaneously, the carbon precursor gas is introduced into the reactor. The flow of reactants within the reactor can be controlled such that the deposition of the carbon products on the walls of the reactor is reduced. The carbon nanotubes thus produced can be collected and separated.
The metal nanoparticles supported on the oxide powder can be aerosolized by any of the art known methods. In one method, the supported metal nanoparticles are aerosolized using an inert gas, such as helium, neon, argon, krypton, xenon, or radon. Preferably argon is used. Typically, argon, or any other gas, is forced through a particle injector, and into the reactor. The particle injector can be any vessel that is capable of containing the supported metal nanoparticles and that has a means of agitating the supported metal nanoparticles. Thus, the catalyst deposited on a powdered porous oxide substrate can be placed in a beaker that has a mechanical stirrer attached to it. The supported metal nanoparticles can be stirred or mixed in order to assist the entrainment of the catalyst in the transporter gas, such as argon.
Thus, the nanotube synthesis generally occurs as described in the co-pending and co-owned application U.S. Ser. No. 10/727,707, filed on Dec. 3, 2003. An inert transporter gas, preferably argon gas, is generally passed through a particle injector. The particle injector can be a beaker or other vessel containing the growth catalyst supported on a powdered porous oxide substrate. The powdered porous oxide substrate in the particle injector can be stirred or mixed in order to assist the entrainment of the powdered porous oxide substrate in the argon gas flow. Optionally, the inert gas can be passed through a drying system to dry the gas. The argon gas, with the entrained powdered porous oxide, can then be passed through a pre-heater to raise the temperature of this gas flow to about 400� C. to about 500� C. The entrained powdered porous oxide is then delivered to the reaction chamber. A flow of methane or another carbon source gas and hydrogen is also delivered to the reaction chamber. The typical flow rates can be 500 sccm for argon, 400 sccm for methane, and 100 sccm for He. Additionally, 500 sccm of argon can be directed into the helical flow inlets to reduce deposition of carbon products on the wall of the reaction chamber. The reaction chamber can be heated to between about 300� C. and 900� C. during reaction using heaters. The temperature is preferably kept below the decomposition temperature of the carbon precursor gas. For example, at temperatures above 1000� C., methane is known to break down directly into soot rather than forming carbon nanostructures with the metal growth catalyst. Carbon nanotubes and other carbon nanostructures synthesized in reaction chamber can then be collected and characterized.
In another aspect, a range of particle diameters within the distribution of the catalyst sizes can be selected for the synthesis of SWNTs by selecting the temperature at which the production of the SWNTs is carried out. The synthesis of the catalyst nanoparticles typically results in a Gaussian distribution of particle sizes. Thus, for example, the synthesis of 1 nm Fe catalysts can have a distribution of particle diameters ranging from about 0.01 nm to about 5 nm, with the majority of particle diameters centering around 1 nm. Normally, the catalysts would be further processed to obtain a tighter distribution of catalyst particle sizes. In contrast, the present methods and process allow for the selection of a narrow distribution of catalyst particles without further processing. In the inventive methods, the reaction temperature can be selected such that it is near or above the eutectic point and so that catalyst particle sizes smaller than the mean are first used for the synthesis of SWNTs. As these catalysts become exhausted, the reaction temperature can be raised such that catalyst particles of sizes near the mean are used for the synthesis of SWNTs. The reaction temperature can be further raised such that catalyst particles of sized near the upper range are used for the synthesis of SWNTs. The methods and processes of the present invention thus have the advantage that the particle size of the catalyst need not be tightly controlled during the synthesis of the catalyst, thereby providing for economical production of SWNTs.
In one aspect of the invention, the diameter distribution of the synthesized SWNTs is substantially uniform. Thus, about 90% of the SWNTs have a diameter within about 25% of the mean diameter, more preferably, within about 20% of the mean diameter, and even more preferably, within about 15% of the mean diameter. Thus, the diameter distribution of the synthesized SWNTs can be about 10% to about 25% within the mean diameter, more preferably about 10% to about 20% of the mean diameter, and even more preferably about 10% to about 15% of the mean diameter.
Carbon SWNTs were synthesized with the yields ranging from about 4 wt % to about 15 wt % (wt % carbon relative to the iron/alumina catalyst). Analysis of transmission electron microscopy (TEM) images of SWNTs produced by using 9 nm iron nanoparticles showed bundles with an average diameter of about 10 nm to about 15 nm. Analysis of TEM images of SWNTs produced by using 5 nm iron catalyst showed average diameter of about 7 nm to about 12 nm. Analysis of TEM images of SWNTs produced by using 1 nm iron nanoparticles showed bundles with diameter about 5 nm to about 10 nm as well as many individual SWNTs. In all cases, a broad distribution of SWNTs diameters from 0.8 to 2 nm was observed. The diameters estimated from TEM were confirmed from the radial breathing modes observed by Raman Spectroscopy spectra, using six different laser excitations (λ=1064; 785; 614, 532, 514 and 488 nm). In
The magnetic properties of the catalyst nanoparticles were also measured after the SWNTs growth using SQUID (
The correlation between the magnetic properties and particle diameter for ultrafine metal powders has always studied. In particular, the coercivity of the metal powders (Hc) has been found to depend strongly on particle size (Gangopadhyay et al. Phys. Rev. B 45, 9778 (1992)). According to the model developed by Kneller and Luborsky (J. Appl. Phys. 34, 656 (1963)), the decrease in Hc with decreasing particle size, is due to the thermal effects observed in particles with a size below the single domain particle, which for iron is approximately 20 nm. The following expression for the coercivity (Hc) vs. temperature (T) is employed:
H c =H c o[1−(25kT/KV)1/2] (1)
where K is the bulk anisotropy constant, V is the volume of particles and Hc o is the zero-temperature coercivity. At room temperature, the smaller particles have smaller coercive forces. Therefore, without being bound to any theory, the increase of coercive forces of the catalysts and the phase transitions from paramagnetic to superparamagnetic and superparamagnetic to ferromagnetic after nanotubes growth, can be attributed to the increase in the diameter of catalyst particles. Thus, the growth of nanotubes may be accompanied by the migration and liquefaction of iron catalyst nanoparticles that results in the formation of larger particles.
The Raman spectra of SWNTs has three major peaks, which are the G-band at about 1590 cm−1, D-band at about 1350 cm−1, and the Radial breathing mode (RBM) at about 100-300 cm−1. RBM frequency is proportional to an inverse of the diameter of SWNTs and can thus be used to calculate the diameter of the SWNT. Normally, a red shift in RBM peak corresponds to an increase in the mean diameter of SWNTs. The tangential mode G-band related to the Raman-allowed phonon mode E2g can be a superposition of two peaks. The double peak at about 1593 and 1568 cm−1 has been assigned to semiconductor SWNTs, while the broad Breit-Wigner-Fnao line at about 1550 cm−1 has been assigned to metallic SWNTs. Thus, G-band offers a method for distinguishing between metallic and semiconducting SWNTs. The D-band structure is related to disordered carbon, the presence of amorphous carbon, and other defects due to the sp2-carbon network. The ratio of the G-band to D-band in the Raman spectra (IG:ID or G/D ratio) of SWNTs can be used as an index to determine the purity and quality of the SWNTs produced. Preferably, IG:ID is about 1 to about 500, preferably about 5 to about 400, more preferably greater than about 10.
Using the methods and processes of the invention, SWNTs with IG:ID of about 10 to about 40 can be manufactured. The quality of the SWNTs depends on the particle size of the catalyst. The particle sizes of the catalyst particles can be determined using SQUID. The synthesis process can be continued until the particle size distribution of the catalysts is within a narrow range. The use of catalyst particles thus prepared provides SWNTs of greater purity and quality.
The carbon nanotubes and nanostructures produced by the methods and processes described above can be used in applications that include Field Emission Devices, Memory devices (high-density memory arrays, memory logic switching arrays), Nano-MEMs, AFM imaging probes, distributed diagnostics sensors, and strain sensors. Other key applications include: thermal control materials, super strength and light weight reinforcement and nanocomposites, EMI shielding materials, catalytic support, gas storage materials, high surface area electrodes, and light weight conductor cable and wires, and the like.
Below are examples of specific embodiments for carrying out the present invention. The examples are offered for illustrative purposes only, and are not intended to limit the scope of the present invention in any way. Efforts have been made to ensure accuracy with respect to numbers used (e.g., amounts, temperatures, etc.), but some experimental error and deviation should, of course, be allowed for.
Catalysts were prepared by impregnating support materials in metal salt solutions. Three different groups of catalyst particles were synthesized and used for growing SWNTs by CVD. Two groups of narrow dispersed iron catalysts, with average diameters of about 5 nm and about 9 nm, were obtained by thermal decomposition of iron acetate in glycol solution under nitrogen atmosphere. The reaction time and iron acetate/glycol ratio were changed to control the sizes of nanoparticles. In a typical procedure, FeAc2 in methanol was used at a molar ratio of Fe:Al2O3 of 1:15. Under a nitrogen atmosphere, FeAc2 was added to dietheylene glycol mono-n-butyl ether in the molar ratio of 1 mM:20 mM. The reaction mixture was mixed under the nitrogen atmosphere using a magnetic stir bar, and heated under reflux for 90 minutes. The reaction mixture was then cooled to room temperature, and Al2O3 (15 mM) was added at once (molar ratio Fe:Al2O3=1:15). The reaction solution was stirred at room temperature for 15 minutes, and then heated to 150� C. for 3 hours. The reaction was cooled to 90� C. while flowing a stream of N2 over the mixture to remove the solvent. A black film formed on the walls of the reaction flask. The black film was collected and ground with an agate mortar to obtain a fine black powder.
The third group of catalyst was prepared by a common wet catalyst method, using iron (II) sulfate and alumina support powder (molar ratio Fe:Al2O3=1:15), with the in-situ formation of the iron nanoparticles inside the pores of the support as described in A. R. Harutyunyan, B. K. Pradhan, U. J. Kim, G. Chen, and P. C. Eklund, NanoLetters 2, 525 (2002).
The magnetization curves of the three groups of catalysts prepared above were obtained using SQUID, and are shown in
Carbon nanotubes were synthesized by using the experimental setup described in Harutyunyan et al., NanoLetters 2, 525 (2002). CVD growth of SWNTs, with the three different catalysts, used methane as a carbon source (T=800� C., methane gas flow rate 60 sccm). In all cases, carbon SWNTs were successfully synthesized with the yields ˜4, 7 and 15 wt % (wt % carbon relative to the iron/alumina catalyst) for the catalysts with the diameters 9, 5 nm and for catalyst made by of iron-sulfate decomposition, respectively. Analysis of many transmission electron microscopy (TEM) images of SWNTs produced by using 9 nm iron nanoparticles showed bundles with an average diameter of ˜10-15 nm, while in case of 5 nm iron catalyst was ˜7-12 nm. The iron-sulfate decomposed catalyst showed bundles with diameter ˜5-10 nm as well as many individual SWNTs. In all cases, a distribution of SWNTs diameters from 0.8 to 2 nm were observed. A Raman spectra of carbon SWNTs using λ=785 nm laser excitation is shown in
Supported catalyst having a molar ratio of Fe:Al2O3 of 1:14.2 was prepared using the method described in Example 1. The magnetization curve is shown in
Supported catalyst having a molar ratio of Fe:Al2O3 of 1:15 (
The magnetization behavior is reflected in the quality of the SWNTs produced. The use of the supported catalyst Fe:Al2O3 having a molar ratio of 1:14.2 yielded IG:ID ratio of 5, whereas, the use of the supported catalyst Fe:Al2O3 having a molar ratio of 1:14.2 yielded IG:ID ratio of 8, and the use of the supported catalyst Fe:Mo:Al2O3 having a molar ratio of 1:0.2:16.9 yielded IG:ID ratio of 21.5 (
While the invention has been particularly shown and described with reference to a preferred embodiment and various alternate embodiments, it will be understood by persons skilled in the relevant art that various changes in form and details can be made therein without departing from the spirit and scope of the invention. All printed patents and publications referred to in this application are hereby incorporated herein in their entirety by this reference.
|Cited Patent
|Filing date
|Publication date
|May 21, 1993
|Jun 13, 1995
|International Business Machines Corporation
|Carbon fibers and method for their production
|Nov 26, 2002
|Dec 13, 2005
|Honda Motor Co., Ltd.
|Method for synthesis of metal nanoparticles
|Oct 20, 2003
|Apr 15, 2008
|The Board Of Regents Of The University Of Oklahoma
|Method for producing single walled carbon nanotubes
|Jun 7, 2002
|Dec 5, 2002
|The Board Of Trustees Of The Leland Stanford Junior University
|Carbon nanotubes and methods of fabrication thereof using a catalyst precursor
|Gangopadhyay, S. et al., "Magnetic Properties of Ultrafine Iron Particles," Physical Review B, 1992, vol. 45, p. 9778-9787.
|Harutyunyan, A. et al., "CVD Synthesis of Single Wall Carbon Nanotubes under 'Soft' Conditions," Nano Letters, 2002, vol. 2, No. 5, pp. 525-530.
|Harutyunyan, A. et al., "CVD Synthesis of Single Wall Carbon Nanotubes under 'Soft' Conditions," Nano Letters, 2002, vol. 2, No. 5, pp. 525-530.
|Hilbert, C. et al., "DC SQUIDS as Radiofrequency Amplifiers," Journal of Low Temperature Physics, 1985, vol. 61, Nos. 3/4, pp. 263-280.
|Hilbert, C. et al., "Measurements of the Dynamic Input Impedance of a DC Squid," Journal of Low Temperature Physics, 1985, vol. 61, Nos. 3/4, pp. 237-262.
|Kneller, E.F. et al., "Particle Size Dependence of Coercivity and Remanence of Single-Domain Particles," Journal of Applied Physics, 1963, vol. 34, pp. 656-685.
|Li et al., 'Growth of Single-Walled Carbon Nanotubes from Discrete Catalytic Nanoparticles of Various Sizes' in J. Phys. Chem. B vol. 103 pp. 11424-11431 2001.
|Li et al., 'Growth of Single-Walled Carbon Nanotubes from Discrete Catalytic Nanoparticles of Various Sizes' in J. Phys. Chem. B vol. 103 pp. 11424-11431 2001.
|U.S. Appl. No. 10/727,707, filed Dec. 3, 2003.
|Citing Patent
|Filing date
|Publication date
|Apr 5, 2010
|Mar 25, 2014
|Seerstone Llc
|Method for producing solid carbon by reducing carbon oxides
|Mar 15, 2013
|Jul 28, 2015
|Seerstone Llc
|Methods for producing solid carbon by reducing carbon dioxide
|Mar 15, 2013
|Dec 29, 2015
|Seerstone Llc
|Methods of capturing and sequestering carbon
|U.S. Classification
|423/447.3, 977/843
|International Classification
|Cooperative Classification
|European Classification


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DasMahapatra, Pronabesh MD, MPH*; Chiauzzi, Emil PhD*; Pujol, Lynette M. PhD†; Los, Cristina BS*; Trudeau, Kimberlee J. PhD*
Objectives: Little is known about the moderators and mediators of change in online pain interventions based on cognitive-behavior therapy (CBT). We hypothesized that the effects of painACTION.com, an online pain self-management program, on pain-related outcomes would be mediated by changes in depression, anxiety, and stress, as well as the use of coping strategies. We also examined potential moderators of change.
Methods: First, the efficacy of painACTION.com and moderators of the intervention effects were evaluated using a pooled sample from previous back, neuropathic, and arthritis pain studies. Next, we explored whether the intervention effect on the primary outcomes, pain severity, and patient global impression of change (PGIC), was mediated by coping strategies or emotional functioning.
Results: Compared with controls, experimental participants evidenced significant improvement in pain, emotional functioning, and coping strategies from baseline to follow-up. There were no clear moderators of intervention effects. Changes in emotional factors, particularly stress levels, mediated the relationship between the intervention and outcome (pain severity) over time.
Discussion: This study supports the effectiveness of online interventions when CBT and self-management targets pain levels, emotional factors, and wellness-focused coping. The importance of stress as a mediator of pain severity is discussed. The absence of moderators may indicate that the intervention is effective for a wide variety of patients with chronic pain.
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Irwin B. Klein, Minneapolis Fire, 1962
It's hard to believe that I just saw this photo for the first time a few months ago and I'm surprised that it's not more popular among Minnesotans.
Irwin B. Klein, Minneapolis Fire, 1962
It's hard to believe that I just saw this photo for the first time a few months ago and I'm surprised that it's not more popular among Minnesotans.
If you've ever been to the Uptown Theater in Minneapolis, you know how special the place is.
Last year I saw a really cool short film about it as part of a curated evening at a local theater and I forgot to post about it at the time.
NED ABDUL NEEDS MORE RETAIL SPACE OR: How To Say Goodbye To An Old Friend from Sepulchral Voice/Dan S on Vimeo.
In the past two weeks I've seen two shows at the Dakota Jazz Club. I used to go there all the time over in the old location when I was studying with a couple of jazz drummers who played there frequently.
Last week I saw Rebirth Brass Band. While it wasn't as amazing as seeing them in their hometown of New Orleans at the Maple Leaf (they have a standing Tuesday night gig there), it was great to see them and they did the impossible: The got a Minnesota audience out of their seats and dancing in what's usually a very relaxed room.
I looked at other shows coming up and was really excited to see that drumming legend Brian Blade was playing there a few days later with his Fellowship band. Easily one of the top 5 shows I've seen. That band is so seasoned as a group and each player is a master of their instrument.
Seeing live music is something I didn't realize that I missed so much. I'll be going a lot more often.
I've missed having a place to share random things without feeling like I'm clogging Facebook, so I've decided to fire up this blog again.
I'll also be adding a pretty substantial gallery of my old Minneapolis graffiti photos from around 2006-2008. There are lots of gems in my archives, though I wish I had been a more thoughtful photographer back then. I think I'll be uploading them to Flickr and embedding galleries on another page. Stay tuned.
In the meantime, here are some photos of the amazing Shiro in 2006 at B-Girl Be hosted by Intermedia Arts.
There's been a lot of hype about Fuji's new camera, the Finepix x100.
It looks absolutely amazing and I can't wait to try one out. The sample images are online and while there's nothing mind blowing, they look pretty good.
Soon to be a documentary.
"The Shut Up Little Man recordings feature the real-life comical rants, hateful harangues, drunken soliloquies, and audible fistfights of Raymond and Peter – two booze-swilling homicidal roommates in a low-rent district of San Francisco. These infamous recordings were made by their much-menaced next door neighbors, Eddie Lee and Mitchell D. The dialogs of Raymond and Peter have been widely championed for their poignant absurdity and stark hilarity. Profiles have appeared in Spin ("This epic documentary is as disturbing as it is hilarious"), Rolling Stone, Vanity Fair ("grimly fascinating"), The LA Times, The Washington Post ("hilarious, but profoundly disturbing"), Playboy, The Wire and on Ira Glass's radio program "This American Life." Sarah Vowell, the essayist and cultural commentator, included a segment about Shut Up Little Man in her book Radio On, calling it "some of the strangest bickering I've ever heard." The recordings have inspired comic illustrations by Daniel Clowes (Ghost World) and Ivan Brunetti (Schizo), animation features by Kevin Peaty (principle animator of "The Lion King" and other Disney classics), numerous songs (e.g. Devo's "Shut Up Little Man" and Nirvana's "Dough, Ray, and Me"), theatrical plays, and film shorts. Shut Up Little Man is widely considered to be a classic of the audio verite and field recording genres, and the recordings continue to inspire shock, laughter, and amazement at the raw humanity and dark comedy contained therein."
Found this song by accident yesterday and can't get enough of it.
[audio: TinnieTempahPassOutStinkahbellSpliffRemix.mp3]
More info on the artist: http://www.myspace.com/stinkahbell
Here's how it happened:
1. A friend posted a pic on Facebook.
2. I followed it to a Tumblr page.
3. I went to another Tumblr page linked to from #2.
4. That page had a song in the background.
5. I loved it.
6. I typed some of the lyrics into Google.
7. I found the song.
8. I now love dubstep. What artists should I check out?
Until I decide what to do with this domain, here are links to the older versions of the site:
I saw this torn page sitting on top of the garbage at the post office. I couldn't resist taking it. Now there are so many questions:
Who threw it away, Sean or the recipient?
If it was Sean, did he decide not to send it? Did he rewrite this page because he screwed up the first sentence?
If you still haven't seen the Urban Explorers documentary by Melody Gilbert, the Riverview Theater is showing it on December 6th at 7pm. If you miss that, it's coming out on DVD soon. Either way, don't miss it.


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Category: WebStorage
Analysis of the differences between MySyncFolder and My Collection
Factoring in different storage needs, ASUS WebStorage divides its space into two folders: MySyncFolder and My Collection. Because most subscribers to ASUS WebStorage tend to store their data only in MySyncFolder, this article is intended to help better understand the differences between the two folders by detailing their respective features, so that smarter use of the two folders serving different purposes will save your drive space and enable more convenient access to your data.
ASUS Cloud care about your health!
ASUS Cloud joined Academia Sinica, Taipei City Government and Realtek Semiconductor Corp., in holding the "Air Box PM2.5" press conference. The objective of the project is to increase public awareness on environmental issues.
Updated iOS version for even smoother user experience
In order to better suit the habits of iOS users, WebStorage has updated its iOS version again while retaining the version's original flat and lineal design to keep the crisp, no-nonsense appearance.
On the other hand, the update has removed the sidebar and placed all function icons at the bottom of the display, so that they can be easily viewed in a glance. More details about the update are introduced as below.
WebStorage Accumulate Storage by your different ASUS devices
If you have more than one ASUS devices, these may have different free storage spaces on WebStorage, and such scattered spaces could only be accessed by their different accounts, or you would have to choose a device providing the largest storage space on WebStorage and forego other free spaces.
Aware of such inconvenience, WebStorage now has a solution to have your free storage spaces coming with different ASUS devices integrated into a same account, and the account can have your free spaces integrated up to 3TB for you to enjoy even more cloud data securely stored on WebStorage.
Four major functions of ASUS WebStorage effectively tackle ransomware attacks
Increasingly rampant computer viruses are nothing new nowadays, but most of the attack victims can still bring their computers back to life by operating system reinstallation and retrieving the files backed up somewhere else. However, recently some ransomware can encrypt or even delete the files on breached computers, and such encrypted files would become useless forever if a decryption ransom is unavailable.
There is no perfect solution to ransomware, but four major functions of ASUS WebStorage can easily recover your data encrypted or deleted by ransomware and you need not pay a dime.
Top Tips & Tools for PowerDirector to Making Enchanting Videos!
If you are a beginner to video editing, or if you don't have a lot of time to create new videos, take a look at PowerDirector's Express Projects. They let you quickly create professional-quality videos in just three simple steps! You can edit the preset effects in each Express project template with fully customizable design tools. Mix and match sequences to tell your story your way.


text:
Mike LaRocco won the World Supercross Championship today in Leipzig, Germany, his second place finish to Jeremy McGrath enough to wrap up his first world title.
With David Vuillemin not in attendance and with a new points system in place (25 to the winner, and then 20, 16, 13,11, etc. like FIM road racing and the 2001 MX GPs), LaRocco and Greg Albertyn were the favorites for the title even with McGrath turning out to be the quickest rider during practice.
In the first semi, LaRocco got a bad start with the race being led by Joshua Coppins – followed by Rodriguez, Turpin and Lalloz. Coppins kept the lead for two laps, but then LaRocco went past, easily winning the race.
McGrath grabbed the holeshot in the second semi and won the race quite handily. Meanwhile, Albertyn and Thain battled for second, with Thain crashing on the second lap.
McGrath again nailed the holeshot in the main, followed in the first corner by LaRocco, Albertyn and Coppins. LaRocco was pushing really hard to follow McGrath, but crashed on the third lap.
LaRocco remounted in 17th and with Albertyn sitting in second it looked as though the South African would win the World Championship. LaRocco, however, didn't give up and he fought his way all the way back to second place – giving him the title.
"I didn't know my position, said LaRocco after the race, and I was giving 110% during all the race as I wanted to take the title."
Larocco passed Albertyn on the 16th lap, then got around Thierry Bethys.
Naturally, McGrath was happy with the win.
"It's always really good to finish the season on a win, especially after my problems in the last European races," McGrath said. "I like Leipzig, the track is a mix of American and European track and the atmosphere is always crazy here."


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text: Article/Report | October 2007Intervention for Verb Argument Structure in Children With Persistent SLI: A Randomized Control Trial Susan H. Ebbels, Heather K. J. van der Lely, and Julie E. Dockrell Author Notes Contact author: Susan Ebbels, Moor House School, Mill Lane, Hurst Green, Oxted, Surrey RH8 9AQ, United Kingdom. E-mail: email@example.com. © 2007 American Speech-Language-Hearing Association Article Information Language Disorders / Specific Language Impairment / Language Article/Report | October 2007 Intervention for Verb Argument Structure in Children With Persistent SLI: A Randomized Control Trial Journal of Speech, Language, and Hearing Research, October 2007, Vol. 50, 1330-1349. doi:10.1044/1092-4388(2007/093) History: Received March 27, 2006 , Revised October 5, 2006 , Accepted February 5, 2007 Journal of Speech, Language, and Hearing Research, October 2007, Vol. 50, 1330-1349. doi:10.1044/1092-4388(2007/093) History: Received March 27, 2006; Revised October 5, 2006; Accepted February 5, 2007 Web of Science® Times Cited: 39 View Article Figures Tables PDF PDF Supplemental Data Supplements Multimedia Share Email Twitter Facebook Pinterest Tools Get Citation Citation Ebbels, S. H., van der Lely, H. K. J., & Dockrell, J. E. (2007). Intervention for Verb Argument Structure in Children With Persistent SLI: A Randomized Control Trial. J Speech Lang Hear Res, 50(5), 1330-1349. doi: 10.1044/1092-4388(2007/093). Download citation file: RIS (Zotero) EndNote BibTex Medlars ProCite RefWorks Reference Manager © 2016 American Speech-Language-Hearing Association × Alerts User Alerts You are adding an alert for: Intervention for Verb Argument Structure in Children With Persistent SLI: A Randomized Control Trial You will receive an email whenever this article is corrected, updated, or cited in the literature. You can manage this and all other alerts in My Account The alert will be sent to: Confirm × Sign In or Create a free account to receive alerts. × PurposeThe authors aimed to establish whether 2 theoretically motivated interventions could improve use of verb argument structure in pupils with persistent specific language impairment (SLI).MethodTwenty-seven pupils with SLI (ages 11;0–16;1) participated in this randomized controlled trial with "blind" assessment. Participants were randomly assigned to 1 of 3 therapy groups: syntactic–semantic, semantic, and control. All pupils received 9 weekly half-hour individual therapy sessions. They were assessed on a specifically designed video test pretherapy, posttherapy, and at follow-up.ResultsPupils receiving the syntactic–semantic and semantic therapies made significant progress (d > 1.0), which was maintained at follow-up and generalized to control verbs. Both therapies improved linking of arguments to syntax, and the syntactic–semantic therapy tended to increase use of optional arguments. Pupils receiving the control therapy made no progress.ConclusionBoth methods of argument structure therapy were effective. Comparisons of their effectiveness in specific areas led to the hypotheses that the pupils' initial difficulties with linking resulted from ill-defined semantic representations, whereas their limited use of arguments may have resulted from syntactic difficulties. When therapy is theoretically grounded, it can inform theories, be time limited, and be effective for older children with SLI. Acknowledgments This study was completed in partial fulfillment for a PhD by Susan Ebbels at the Center for Developmental Language Disorders and Cognitive Science, University College London. The PhD was jointly supervised by Julie Dockrell and Heather van der Lely. Special thanks to Moor House School, which supported Susan Ebbels's PhD. We would like to thank Courtenay Norbury, who acted as the blind assessor for this project, as well as Mike Coleman and Chris Fryer, who assisted with the technical construction of the argument structure assessment. We would also like to thank the pupils who took part in the study and Moor House School, Surrey, United Kingdom, for providing the accommodation and equipment for the intervention. Subscribe to view more For full access to this article, log in to an existing user account, purchase an annual subscription, or purchase a short-term subscription. Order a Subscription Subscribe Pay Per View Entire Journal of Speech, Language, and Hearing Research content & archive 24-hour access $30.00 Buy Now This Article 24-hour access $15.00 Buy Now Become a Visiting Scholar Sign In or Create an Account Please sign in using your ASHA.org login. If you do not have an ASHA login, you may register with us for free by creating a new account. Sign In or Create an Account Related Articles Sentence Comprehension in Specific Language Impairment: A Task Designed to Distinguish Between Cognitive Capacity and Syntactic Complexity Journal of Speech, Language, and Hearing Research, April 2013, Vol. 56, 577-589. doi:10.1044/1092-4388(2012/11-0254) Syntactic Structural Assignment in Brazilian Portuguese-Speaking Children With Specific Language Impairment Journal of Speech, Language, and Hearing Research, August 2012, Vol. 55, 1097-1111. doi:10.1044/1092-4388(2011/10-0215) Spreading the Word: Raise Your Profession's Profile With Local Angles on National NewsHow to use your local know-how to get the media to pay attention. The ASHA Leader, February 2013, Vol. 18, online only. doi:10.1044/leader.STW.18022013.np Verbal Working Memory and Sentence Comprehension in Children With Specific Language Impairment Journal of Speech, Language, and Hearing Research, April 2000, Vol. 43, 293-308. doi:10.1044/jslhr.4302.293 An Evaluation of the Facilitative Effects of Inverted Yes-No Questions on the Acquisition of Auxiliary Verbs Journal of Speech, Language, and Hearing Research, February 2002, Vol. 45, 160-174. doi:10.1044/1092-4388(2002/012) Related Topics Language Disorders Specific Language Impairment


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Vermont officials get revenue updateJuly 23,2013The Associated Press
MONTPELIER — Two consulting economists say Vermont's revenue forecast is improving, with the general fund and transportation fund expected to be up in fiscal year 2014.
The economists recommended to lawmakers and the governor on Tuesday an increase of 3 percent in the general fund to $4 million for the fiscal year and a 7.4 percent upgrade to the transportation fund to $17.2 million from their January forecast.
But the economists recommended downgrading the education fund by 3 percent or $500,000.
Economist Thomas Kavet says the state ended the fiscal year 1.5 percent above expectations. But he said the economic recovery has been slow.
He says the state would normally be having accelerated rates of growth at this stage but says it's not because of "headwinds that exist from federal fiscal policy."MORE IN This Just InWindsor 3-2
Editors note: Area candidates in House races were offered an opportunity to... Full StoryWindham-4
Editors note: Area candidates in House races were offered an opportunity to... Full StoryPOULTNEY A Wallingford woman was charged with leaving the scene of an crash. Full Story
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text:
If our forums were any indication, Dragon Age: Origins was not only destined to be terrible, but there was a good chance its cloth map would serve as a vehicle for smallpox.
BioWare claimed that Dragon Age was the spiritual successor to their Baldur's Gate series, arguably the best RPGs ever made. That's marketing bullshit, the forum said. Did you see that ridiculous trailer? The game would reportedly take 80+ hours to complete including all sidequests. Every game claims it will be 100+ hours, then turns out to be 12. By our math Dragon Age should only be half an hour long. It would be extremely challenging, with the PC serving as the lead platform. Ha! They'll focus on consoles and make it easy so they can cater to a larger audience, with a lame PC port that has no support for flight sticks.
As it turns out - for the first time in the history of the universe - people with extreme opinions about things they hadn't experienced firsthand were wrong. The game is all of the things it claimed to be, and on top of that most people seem to think it's pretty fun.
One of my favorite parts of the game is the codex, a section of your character's journal that fleshes out the game's setting with information about everything you encounter, as well as excerpts from any books you come across. It's mostly well-written and worth checking out. Mostly. Some of the codex entries left me a little confused.
Angry and hopeless Trump voters take heart: there is a man who is out for justice for America.
People can't stop talking about this Donald Trump character. He's said a lot of crude and hateful things over the years, and demonstrated a tremendous lack of judgment, discipline and decency. If you ask me, he's not fit to be our president. In fact, he's not even fit to be mayor of Buffoontown.
The scariest movie you could possibly watch this Halloween. No really. Up yours Australia!
Nightmares Fear Factory is BACK, baby!
Two hits. Me hitting you. You hitting the floor.
The Something Awful front page news tackles anything both off and on the Internet. Mostly "on" though, as we're all incredible nerds.
Copyright ©2016 Rich "Lowtax" Kyanka & Something Awful LLC.


text:
Raine's GC Fanart
Fanart Index - Organized for your viewing pleasure (old to new)
/forum/grand-chase-f...tml#post176153 - Lire Archranger in action
/forum/grand-chase-f...tml#post177474 - Lire Archranger at ease
/forum/grand-chase-f...tml#post177724 - Arme, being adorable
/forum/grand-chase-f...ml#post1396546 - Dio in Vampire (2010) armor
/forum/grand-chase-f...ml#post1418481 - Amy (sketch), Dressy Elesis (vector), Ryan x Lire
/forum/grand-chase-f...ml#post1420060 - Ryan x Lire banner
/forum/grand-chase-f...ml#post1424502 - Amy (sketch)
/forum/grand-chase-f...ml#post1442290 - Amy & Arme, Christmas (2010) themed
/forum/grand-chase-f...ml#post1480334 - Ryan x Lire wallpaper, sketch compilation
Oh, I can take requests. Just specify the character and the armor. Though I may or may not half-ass the picture depending on my mood. Late update: Bored of GC until further notice (also super busy with life) so all requests have been, and will be on hold until further notice.
---Actual post from 10000000 years ago---
Thought I'd share mine. Well. My one fanart. <_< There might be more, since I recently discovered a new way to draw.
Lire is pure <3
My first sketch on Open Canvas. It's a little different from Photoshop, but it doesn't lag when I use huge strokes, so yay! My stuff is usually not this messy, but I was just playing around/too lazy. =P
It's nice :D
I think she's holding the bow wrong though ...
I just drew the bow as big as possible.. since it's a Great Bow.. and Great is bigger than Bow.. Or something... >___>
its nice, i think he meant.. the hand should be reversed and holding the bow gripping towards her.. now away from her.. thats why it looks awkward. its she is drawing the arrow towards her bow..she wouldnt be able to execute a shot .. realistically looking at things.
Oh yeah.. I realized the hand thing after I finished drawing it. I really wasn't thinking much more than "Oh my god Lire's so cute" while I was drawing.. >.>
I intended the arrow to have stabbed or about to stab someone. Since that's what AR's do. =) Stabbing things with their arrows.
I personally think her stance is fine. Love the artwork ^^
the "messy" look works for this picture. it looks really good. i hope i will be able to draw this well by the time i finish my art course
I love it, it looks cute Good Job ^^
Thank you everyone for the comments. =) They help me get better!
Lire has infected meee.
This time, she's not in fight mode. Another messy open canvas work. Photoshopped stuff takes foreverrrr.
I like the drawings, but on the second one, the left eye looks weird @_@
You draw better than me anyways, so I can't say anything :X
Good work there :3 *thumbs up*
I really like your style!
The colouring's beautiful~~ Well done!
Thanks again for the commentness.
@Haiko: There probably IS something wrong with it. I just don't know it yet. xD
I am wondering why I am drawing so much. This here is my first attempt at a monochromatic picture. Um. It looks wrong, but hey, it's Arme. Another Open Canvas work. You won't be seeing the clean Photoshop stuff here.
I think her shoulders are a bit too high.
Other than that, Arme looks pretty cute in that, even though her English voice is ear-deafening < <;;
Maybe Arme is shrugging doing that 'Iono' thing. Arme reminds me of a character from GunSlingerGirl.
Love all the drawings here. Did you use a pad or mouse?
But AR sucks, don't matter what others says, AR SUCKS D:
SUPER REVIVAL POST?!?! Because making a new topic would be kinda .. eh .. unnecessary.
.. Yeah. Favorite male character, and almost favorite character. XD Just a sketch that I colored in, so there might be mistakes. I can't draw guys at all.
Cujo, I don't know if you still care, but I use a tablet. XD
Tablet or Mouse, regardless, it looks pretty awesome.
I don't mind much about grave digging, especially if it's on your own post with the same contents that you plan to put up anyways.
2 years wow.
By the way, your Lire looks a little like Eve. x_x
Eve from where? o.o The only one I can think of is the one from Black Cat.
Also, image dump time. ^^
Year-old sketch that I found on my mess of a desk. Will I ever finish it? ... WHO THE HELL DO YOU THINK I AM!?!
translation: no
Another old concept I found (but on my computer this time..). I'm leaving in vector-y form. =.= I have the other girls sketched out in their dresses too, but it remains to be seen whether or not I will finish them.
40~ minute doodle. I SHIP THIS PAIRING. :py01: *shot*
Ryan: Heey, hold my hand, the others are watching~
Lire: Wh-what?! That's stupid!
Weird concept, stemming from the ideas of "Starlet" and "muse." 30~ minute doodle, during which time I think I was high or something.
I drew the last two yesterday. :py03:
Woo hoo! More pictures!
Something about Amy's face doesn't look right. I think it's the eyes-to-nose connection. I know there are a lot of art that teaches how to draw that way, but from your other drawings, the style feels too different.
Elesis looks awesome! It kind of reminds me of Toradora! for some reason.
Ryan and Lire has been my favorite couple since forever. Elven love! Second would be Jin and Amy.
Your last Amy reminds me of Luka Megurine (from Vocaloid 2), but nonetheless, still looks professionally done!
I've send a Buddy Invite by the way. Add CujoEX when you get the chance :)
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Why Freemium Is Right for 'Microsoft Flight'
Microsoft Flight won't cost a thing to download upon release, but if you want the full experience, you'll have to pay up--here's why that's a good thing.
Microsoft To Give 'Microsoft Flight' Away for Free?
Microsoft Flight will be available this spring as a free download that lets you zip around the island of Hawaii, says Microsoft.
Out of the Frying Pan? Nintendo 3DS Sells 4 Million Units in U.S.
Nintendo says it sold 12 million total hardware units, Wii and 3DS sales combined, in the U.S. in 2011.
The (Not So) Great Holiday 2011 Xbox LIVE 'Oops'
Ready to kick back with your Xbox 360 over the holiday weekend? Not if you're one of the users barred from accessing Microsoft's Xbox LIVE network due to a glitch.
And Facebook's Top Games of 2011 Are…
Facebook's top games of 2011 include Cityville and The Sims Social, as well as a bunch of stuff you've probably never heard of.
Dragon Age III May Draw Inspiration from Skyrim
BioWare admits the next Dragon Age game may be influenced by Bethesda's epic roleplaying opus.
Ready, Set, Star Wars: The Old Republic Reviews Incoming
Watch out World of Warcraft, EA and Bioware's Star Wars: The Old Republic has your storytelling savoir faire (or lack thereof) in its crosshairs.
Star Wars The Old Republic, One Day and Counting
Star Wars The Old Republic went live last week exclusively for customers who preordered and finally hits store shelves for everyone else tomorrow.
Richard Garriott Could Wind Up Making Ultima Online 2
Ultima creator says he's had high level talks with EA officials about merging his new 'Ultimate RPG' game with original brand name.
Bye-Bye Avatar: Modern Warfare 3 Takes $1 Billion Record
Modern Warfare 3 racks up $1 billion in sales in less time than James Cameron's megabucks 3D film.
Google's Chrome Will Run Console Games! Wait, What?
Google unveils new Chrome browser technology running console games like Xbox Live Arcade title Bastion.
OnLive Now on Android Tablets, iOS Devices Soon
Cloud gaming service brings titles like Batman Arkham City and Assassin's Creed Revelations to tablets and smartphones.
Another Perfect 40: Final Fantasy XIII-2 Gets Famitsu Thumbs Up
Final Fantasy XIII sequel gets perfect score from legendary Japanese games mag.
Xbox 360 Dashboard Overhaul Will Let You Get Stuff Faster
Microsoft's Xbox 360 dashboard switch-out happens today, radically changing the way you'll interface with the system once again.
Minecraft Plus LEGO Equals Minecraft LEGO!
You've built all kinds of stuff in Minecraft's blocky virtual territories, but what about in the real world?
Articles by Matt PeckhamNext Page
Most Commented


text:
Valentine's Baking Class, Lunar New Year Dinners, and A New Brunch
Hands-On Valentine's Baking Classes
Sure, you can go out to dinner with your sweetie in honor of Valentine's Day. But why not bake something together for an especially sweet time instead?
Rachel's Cakes of Burlingame is offering just that — two-hour, hands-on classes designed for couples to bake and decorate homemade sugar cookies.
The classes are: 6 p.m. to 8 p.m. Feb. 13; and 1 p.m. to 3 p.m. and 5 p.m. to 7 p.m. on Feb. 14.
Each class is limited to four couples, and includes lessons in rolling, baking and decorating. Appetizers and beverages also will be served. You can take home your decorated cookies, as well as any unfinished ones with a supply of icing to complete them at home.
The class is $150 per couple. Reservations are required by calling (650) 393-4514. If you can't make it to any of these, you'll be glad to know Rachel's offers other classes throughout the year.
On the flip side, if you want to leave the baking to someone else for Valentine's Day, owner Rachel Richanbach will be happy to create a rustic or custom cake.
I had a chance to try some samples recently. Her cakes are all very moist, and taste quite homey.


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If she's a black queen... (I tried not to laugh here)
Anyways, good video. Very helpful!
Good video!
You said the pawn on g1 unstead of knight on g1. But good video, and just a little weird thing happpening, you voice went up and down.
After playing chess many years, I gave in and I am going to embark on my study plan, in earnest. The power I got from this video was the importance of the red lines, I always visualized the travel of a piece to a point, maybe if I actually think how the resultant "red arrow form" would look due to overall configuration, would lead to faster awareness of current game. Thanks for video
very good thx
Thanks so much
Thank you.
very helpfull.
it is very helpful.
Part one is realy helpful i enjoyed and please tell to me how to learn more deeply and i want to enjoy playing Chess.
Perfect vid for beginners!
How did Todd clear the board of all the pieces inncluding the King ? I know he is using the live analysis board, but I cannot figure out how to clear off the king. Please advise.
I'm switching my Netflix addiction for a chess addiction. Better for the brain .
It's my first visit to chess.com. I hope I could play chess - at least for fun
by FM Todd Andrews
In just two short video lessons, Fide Master Todd Andrews will have you ready to sit down for your first game. This first video covers the chessboard, and basic rules including moving the bishop, rook, and queen.
Rules & Basics
Related: Check out Part 2! »
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FM Todd Andrews
Todd's tournament experience began with a bang, winning the u1200 section of his first tournament. In one year of feverish study and play he gained an unprecedented 1000 rating points. Since establishing himself as a strong master, he has turned to teaching, and found it extremely rewarding as well. He has also been quite successful: his students have won national championships.
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West Fork fire rages, town braces for long evacuation
June 23, 2013
DEL NORTE — A colossal wildfire raging near popular tourist areas of the southwestern Colorado mountains more than doubled in size over the weekend, driven by winds and fueled by dead trees in drought-stricken forest, authorities said Sunday.
The weather has prevented fire crews from making progress against the blaze, which Sunday night was estimated at 114 square miles.
No structures have been lost in the fire, and no injuries have been reported.
Sunday, officials said most of the intense fire activity occurred on unburned areas inside the perimeter of what are technically three separate lightning-sparked fires.
But with heavy winds expected again today, the perimeter is expected to grow again, said Pete Blume, a commander with the Rocky Mountain Type 1 Incident Command Team.
Although crews Sunday were able to focus on efforts to protect towns like South Fork, the Wolf Creek ski area and homes along Colo. 149, Blume said it doubtful firefighters will be able to establish any containment lines until there's a break in the hot, dry, windy weather, possibly Tuesday.
They remained optimistic, however, that they can protect South Fork, whose 400 residents and hundreds of summertime visitors were forced to flee on Friday after two of the fires joined and began a fast advance toward the town. The blaze Sunday was 2 to 3 miles away, Blume said.
Blume, a commander with the Rocky Mountain Type 1 Incident Command Team, said the wildfire is the worst ever known to hit the Rio Grande National Forest.
"It's not typical to have these kinds of fires here," said Blume, but beetle kill, the 30 to 40 mile an hour winds and extreme drought are "also not the norm."
Firefighters are hoping for a break in the high winds, as well as the anticipated July monsoons, to help them fight back the flames. Until then, Blume said, "with that much beetle kill and drought we could have every resource in the country here and still not put in a containment line."
Still, fire officials believe portions of the blaze will likely burn all summer in forested, nonresidential areas, with full extinguishment probably months away.
The lightning-sparked blaze started June 5, but its rapid advance Friday prompted the evacuations.
Residents and tourists were settling in for a long wait before they can return to their homes, cabins and RV parks.
"They just said they had no idea how long it would be before we could be back in South Fork," said Mike Duffy, who owns the South Fork Lodge.
Duffy said he and his wife, Mary, were able to get their personal possessions before fleeing fast-advancing flames that officials initially feared would overtake the town. But with the fire still within 3 miles of South Fork, they are worried about the long-term impact of a prolong evacuation and news reports about the fire raging around the tourism-dependent town.
Summer visitors include many retirees from Texas and Oklahoma who come to the mountains to flee the heat.
South Fork Mayor Kenneth Brooke estimates that between 1,000 to 1,500 people had to flee, including the summer visitors and permanent residents.
More than 600 firefighters were battling the blaze, and more are coming every day. They also focused on newest arm of the fire as it crept through beetle kill toward the historic mining town of Creede, the last silver boom town in Colorado before the industry went bust in the late 1800s.
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text:
2015 Speakers:
Stanton T. Friedman
Nuclear physicist and lecturer Stanton T. Friedman received his BSc. and MSc. Degrees in physics from the University of Chicago in 1955 and 1956. He was employed for 14 years as a nuclear physicist by such companies as GE, GM, Westinghouse, TRW Systems, Aerojet General Nucleonics, and McDonnell Douglas, working in such highly advanced, classified, eventually cancelled programs as nuclear aircraft, fission and fusion rockets, and various compact nuclear power plants for space and terrestrial applications.
Friedman became interested in UFOs in 1958, and since 1967 has lectured about them at more than 600 colleges and 100 professional groups in 50 U.S. states, 10 Canadian provinces and 18 other countries in addition to various nuclear consulting efforts. He has published more than 90 UFO papers and has appeared on hundreds of radio and TV programs, and in many documentaries. He is the original civilian investigator of the Roswell Incident and co-authored Crash at Corona: The Definitive Study of the Roswell Incident. TOP SECRET/MAJIC, his controversial book about the Majestic 12 group, established in 1947 to deal with alien technology, was published in 1996 and went through six printings. An expanded new edition was published in 2005. Stan was presented with a Lifetime UFO Achievement Award in Leeds, England, in 2002, by UFO Magazine of the UK. He is co-author with Kathleen Marden (Betty Hill's niece) of a book in 2007: Captured! The Betty and Barney Hill UFO Experience. His book Flying Saucers and Science was published in June 2008 and is in its third printing. His most recent book, also co-authored with Kathleen Marden, is Science Was Wrong (2010).
He has provided written testimony to Congressional hearings, appeared twice at the United Nations, and been a pioneer in many aspects of ufology including Roswell, Majestic 12, The Betty Hill-Marjorie Fish star map work, analysis of the Delphos, Kansas, physical trace case, crashed saucers, flying saucer technology, and challenges to the S.E.T.I. cultists. He has spoken at more MUFON Symposia than any other guest.
Kathleen Marden
Kathleen Marden is known around the world for her work as an alien abduction/ET contact researcher, experiencer advocate, author and lecturer. Her educational background in the social sciences has shaped her interest in scientific ufology. Extensive research and investigation into alien abduction has convinced her that abductions are not only real; they are being covered up by the government and a small group of pseudo-skeptics.
Marden earned a B.A. degree in social work from the University of New Hampshire and participated in graduate studies in education while working as a teacher and education services coordinator. During her fifteen years as an educator, she innovated, designed and implemented model educational programs. She also held a supervisory position, coordinating, training and evaluating education staff.
Her interest in UFOs dates back to September 20, 1961, when her aunt, Betty Hill, phoned her nearby home to report that she and husband Barney had encountered a flying saucer in New Hampshire's White Mountains. A primary witness to the evidence of the UFO encounter and the aftermath, Marden has intimate knowledge of the Hill's biographical histories, investigation files, and scientific interest in their sensational experience. Betty's scientific contact experiments may have led to Marden's personal memories of contact—memories that were undisclosed for nearly 50 years. This led to a personal journey of exploration, leaving no stone unturned, to find answers through scholarly work, investigation and social research.
She is associated with the Mutual UFO Network, as Director of Abduction Research and the Foundation for Research into Extraterrestrial Encounters, as an advisory board member and consultant to its research subcommittee. She is the recipient of MUFON's 2012 "Ufologist of the Year" award. Marden has authored three books, Captured! The Betty and Barney Hill UFO Experience, and Science was Wrong, with nuclear physicist/scientific ufologist Stanton T. Friedman, and The Alien Abduction Files, with Denise Stoner, and essays in several additional books. She spearheaded an extensive research project, with Stoner, to identify little known commonalities among experiencers, in 2012. Her articles have been published in the MUFON UFO Journal, Open Minds, Alternate Perceptions and FATE magazines and on several websites. Marden has appeared in television and radio programs in the US, Canada, Australia and the UK, and has lectured throughout the United States. She is recognized as the world's leading expert on the Betty and Barney Hill abduction. You can purchase her books or read her articles at www.kathleen-marden.com.
Grant Cameron
Grant Cameron became involved in ufology in 1975 with personal sightings of an object which locally became known as Charlie Red Star, occurring in Carman, Manitoba. Cameron's research interests turned to the involvement and actions of the President of the United States in the UFO problem. He has made more than 20 trips to the National Archives and most of the various presidential archives looking for presidential UFO material. One highlight of his presidential UFO research was the chance to question Vice President Dick Cheney on his knowledge of the UFO subject. Another highlight was a Freedom of Information Act (FOIA) request to the White House Office of Science and Technology, which yielded 1,000 pages of UFO documents from the Clinton Administration. Many of these findings have been written up on his website, www.presidentialufo.com. Cameron is awaiting word on nearly 100 FOIA requests to the Clinton Presidential Library in Little Rock, AK, related to the UFO-related actions and policies inside the two presidential terms of Bill Clinton.
Cameron was awarded the International Researcher of the Year at the 2012 Leeds UFO Conference and the Researcher of the Year at the 2013 International UFO Congress in Phoenix, AZ. His new research focuses on the source of intelligence we contact and access through what we know as inspiration, telepathy and consciousness here on Earth.
Travis Walton
On November 5, 1975, while working with a logging crew in the Apache-Sitgreaves National Forest in Arizona, Travis Walton was allegedly abducted in front of multiple witnesses by a UFO. After a failed manhunt, Walton returned, dazed and disoriented, five days later, with fleeting memories of alien entities and descriptions of the inside of their craft. He was subjected to a number of polygraph examinations. The Travis Walton event would soon become the very first abduction case to be given serious consideration by credible scientists. His story would force the general public to reevaluate previously close-minded opinions on the subject. Today, his experience is called "the best documented account of alien abduction yet recorded."
In 1978, Walton published Fire in the Sky: The Walton Experience, in which he outlined his own narrative of the event and its aftermath. In 1993, Walton's book was adapted into a film, Fire in the Sky, directed by Robert Lieberman. While the film did not adhere strictly to the actual events of Walton's experience and that of the multiple witnesses, the movie brought the story out to a wider audience and perhaps opened some minds as to the possibility of UFOs, ETs and other lifeforms.
Peter Davenport
Peter Davenport has been director of the National UFO Reporting Center since 1994. Davenport reports UFO sighting cases regularly on the Jeff Rense Radio Show and presents lectures on specific UFO cases, most notably the Phoenix Lights sighting. In addition to being the director of the National UFO Reporting Center, Davenport has served as the director of investigations for the Washington Chapter of the Mutual UFO Network.
Davenport has been witness to several anomalous events, possibly UFO related, including a dramatic sighting over Baja California in February 1990, and several nighttime sightings over Washington State during 1992.
Davenport received his undergraduate education at Stanford University in California, where he earned bachelor's degrees in both Russian and biology, as well as a translator's certificate in Russian translation. His graduate education was completed at the University of Washington in Seattle, where he earned an M.S. degree in the genetics and biochemistry of fish from the College of Fisheries, as well as an M.B.A. degree in finance and international business from the Graduate School of Business.
Davenport has worked as a college instructor, a commercial fisherman, a Russian translator in the Soviet Union, a fisheries observer aboard Soviet fishing vessels, a flight instructor, and a businessman. Davenport was the founding president of a Seattle-based biotechnology company, which currently employs over 300 scientists and technicians. In 1986, Davenport was a candidate for the Washington State Legislature, and in 1992, he was a candidate for the U. S. House of Representatives.
Here are just a few of our UFO Festival speakers from previous years:
Budd Hopkins – world-renowned author and pioneer UFO abduction researcher
Dr. Bruce Maccabee – U. S. Navy Research Physicist and author of The UFO/FBI Connection: The Secret History of the Government's Cover-Up
George Noory – host of nationally syndicated radio program, "Coast to Coast AM"
David Marler – author of Triangular UFOs: An Estimate of the Situation
Kewaunee Lapseritis – authority on the Bigfoot / Sasquatch phenomenon
Peter Davenport – director of the National UFO Reporting Center since 1994
Stanton T. Friedman – Nuclear physicist, UFO researcher and lecturer
Peter Robbins – best-selling author and noted UFO researcher
Dr. Roger Leir – alien implant removal specialist
Peter Davenport – director of the National UFO Reporting Center
Dr. Jesse Marcel, Jr. – the only individual acknowledged by the U.S. government to have handled Roswell wreckage
Dr. David M. Jacobs – noted alien abduction expert and professor at Temple University
Terry Halstead – director of the Trent Case Documentary
Richard Dolan – author of UFOs and the National Security State
Robert Nichol – award-winning director, producer and filmmaker of Star Dreams
Linda Moulton Howe – reporter/editor for Earthfiles.com and investigative reporter for "Coast to Coast AM with George Noory"
Kathleen Marden – UFO researcher and co-author with Stanton Friedman of Captured! The Betty and Barney Hill UFO Experience: The True Story of the World's First Documented Alien Abduction (2007)
James Clarkson – well-known UFO investigator
Colin Andrews – U.K. crop circle expert
Travis Walton – UFO witness and abductee on whom the book and Hollywood film Fire in the Sky were based
Robert Salas – UFO sightings at nuclear weapons facilities
Stan Gordon – the nexus between UFO and Bigfoot sightings as well as the 1965 Kecksburg, Pa., crash
Paola Leopizzi Harris – the 12 Protocols of Exopolitics (i.e., rules for intergalactic policies) as well as the 1945 San Antonio UFO crash
Donald R. Schmitt — former co-director of the J. Allen Hynek Center for UFO Studies and Roswell crash site archaeologist
Yvonne R. Smith — UFO abduction researcher specializing in cases of post-traumatic stress disorder
Tom Reed — part of a well-documented multigenerational alien abduction case that dates back to 1954


text:
What is the issue these are still present under 66c. What's the problem?
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Guest Message by DevFuse
Audio Drop Outs
Started by Rtm , Mar 02 2013 03:07 AM
2 replies to this topic
Posted 02 March 2013 - 03:07 AM
Posted 02 March 2013 - 11:51 AM
More details about your equipment, exact symptoms, and when/where they occur would be very helpful.
HD DVRs: HR44 + AM21; HR24
Receivers: H25-500 HD Receiver
Mobile Devices: Nomad
Additional equipment configuration details
Sun & moon help site your satellite dish
Posted 02 March 2013 - 08:52 PM
It is not inherent. Most of us very rarely ever experience any audio dropouts, and never have.
It's usually safe to talk honestly and openly with people because they typically are not really listening anyway.


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14th Annual Spirit of Volunteerism
November 1st - DeSales University
5:30 to 8:00 PM
Check out ASR's Winning Video from 2015!
2016 Honorary Chair - Ashley Russo, ASR Media
1000 volunteers. 58 projects. One amazing day.
Check out the photos from the 2016 Day of Caring.
For this week's Morning Call column of current volunteer opportunities Click here.