A tape storage and display apparatus by which a plurality of tape decks are displayed to prospective purchasers, and at the same time theft of the individual tape deck is discouraged. The apparatus includes an open framework which forms a plurality of windows through which either side of the plurality of tape decks can be viewed. Each window is defined by the inner peripheral edge portion of a slot. Each slot slidably receives a plurality of tape decks therewithin. Each slot includes opposed pairs of flanges which slidably receive opposed marginal edge portions of the tape decks therewithin. The slots have one end which outwardly opens to permit the tape decks to be slidably removed therefrom. The outwardly opening end of the slot is closed by a lock means.

Tape decks, such as the compact cassettes and the larger eight track tape apparatus, provide an extremely convenient means by which knowledge can be stored. The modern tape deck is especially popular for providing recorded music, and many stores have found it profitable to offer a large stock of tape decks for sale to the public.
A large segment of the buying public is comprised of teenagers who like to browse through the tape decks for considerable lengths of time before making their selection of the particular tape they wish to purchase. A surprising number of these purchasers have discovered that the compact cassette tape deck is sufficiently small to enable it to be easily secreted in one's clothing, and accordingly, unlawful conversion of a large number of tape decks occur wherever tape decks are sold.
Many small stores, such as the modern neighborhood convenient stores, cannot employ more than one or two store personnel and accordingly, it is impossible to monitor all of the customers who may be present in the store at a given time. This lack of personnel encourages theft of the tape decks and for this reason many convenient stores refuse to stock tape decks because of the ratio of theft versus lawful sales.
It would therefore be desirable to provide a means by which tape decks can be displayed to the prospective purchaser, and at the same time discourage the individual tape deck from being stolen. It would be desirable that the tape decks be displayed in a manner which requires absolutely no supervision, which requires a minimum of storage space, and which enables the prospective purchaser to view a vast number of tapes without enlisting the aid of the store personnel. After the purchaser has made his tape selection, it would be desirable to provide a means by which the purchaser could pay the storekeeper and obtain the tape with a minimum expenditure of time. These desirable attributes are the subject of the present invention.


An embodiment may include local row and column circuitry that are local to a memory cell of a memory device. Either the local row circuitry or the local column circuitry may be electrically isolated, at least in part, from at least one remaining portion of the memory device during the establishing of a voltage differential between the local row circuitry and the local column circuitry that is to permit the memory cell to be read during a read of the memory cell. The read may occur subsequent to the establishing of the voltage differential. Many variations, modifications, and alternatives are possible without departing from this embodiment.

In a cross-point memory architecture read operation, a voltage differential is applied between a row and a column of a memory cell in the memory. The logic state of the cell is then determined by measuring a bias voltage and determining whether the bias voltage exceeds a cell threshold voltage.
During this conventional read operation, it is possible that a relatively large capacitive discharge may occur through the memory that is capable of disturbing (e.g., corrupting) the logic state of the cell and/or significantly reducing the number of read operations that can be performed on the cell before the cell's data will need to be rewritten. As can be appreciated, this may significantly degrade the memory's performance and/or increase the complexity of the operations and/or circuitry involved in managing the memory.
Although the following Detailed Description will proceed with reference being made to illustrative embodiments, many alternatives, modifications, and variations thereof will be apparent to those skilled in the art. Accordingly, it is intended that the claimed subject matter be viewed broadly.

Isolating, at least in part, local row or column circuitry of memory cell before establishing voltage differential to permit reading of cell


A novel anthracycline glycoside 2-deoxy-L-fucopyranosyl carminomycinone which is effective for inhibiting the growth of tumors such as leukemia L1210.

1. Field of the Invention
This invention relates to a new anthracycline glycoside antineoplastic agent and, more particularly, to a new oxygen analogue of the anthracycline antibiotic carminomycin.
2. Prior Art
As described in M. G. Brazhnikova et al., J. Antibiot., 27:254-259 (1974), G. F. Gause et al, Cancer Chemother. Rep. 58:255-256 (1974), M. C. Wani et al, J. Am. Chem. Soc. 97:5955-5956 (1975) and West German Pat. No. 2,362,707, the anthracycline glycoside carminomycin is known to be a clinically useful antineoplastic agent. However, it produces certain undesirable side effects, common to many antineoplastics agents, which limit its use in chemotherapy. In particular, it produces a cumulative, dose-related cardiotoxicity which limits the total dosage that can be administered to a patient and the duration of treatment.
Preparation of a glycoside of daunorubicin is described in E. F. Fuchs et al, Carbohydr. Res., 57: C36 (1977). Preparation of glycosides of .epsilon.-rhodomycinone is described in H. S. El Khadem et al, J. Med. Chem., 20:957-960 (1977). Preparation of 2-deoxy-L-fucopyranosyl-.epsilon.-pyrromycinone and 2-deoxy-D-erythro-pentopyransoly-.epsilon.-pyrromycinone, - cdaunomycinone, and - carminomycinone and their dio-O-acetyl derivatives is described in H. S. El Khadem, Carbohydr. Res., 65: C1 (1978).

Board of Control of Michigan Technological University


A method by which stacks of printed sheets can be formed and, at the same time, the risk of soiling of the stacked sheets can be reduced to the maximum extent. To this end a printing machine is proposed, in particular a sheet-fed printing machine, into which unprinted and intermediate sheets are alternatively feed, wherein the printing is registered such that the printing occurs only on the unprinted sheets and not on the intermediate sheets. In this way, the intermediate sheets prevent damage to the print on the printed sheets.

The present invention relates to a method of producing stacks of sheets printed with individual prints, in particular stacks of securities sheets, such as banknotes, from stacks of unprinted sheets, the unprinted sheets running into a printing machine one after another in order to be provided with the individual prints.
The present invention likewise relates to a printing machine for the implementation of the method according to the invention.

Sheet-fed printing press and method carried out using the same


A process for preparing microcapsules comprising a core of highly viscous liquid substance encapsuled with a wall of an aggregate of finely divided silica powder, which comprises adding the highly viscous liquid substance into a powder bed of the finely divided silica powder under stirring with a cutter. The microcapsules thus obtained have such a structure that the core of highly viscous liquid substance is coated with a wall of an aggregate of the finely divided silica powder and a gelatinized layer formed between the wall and the liquid core substance.

The present invention relates to microcapsules comprising a core of a liquid substance and a wall of an inorganic substance and a process for the preparation thereof. More particularly, the present invention relates to microcapsules of excellent properties having a wall of a highly chemically stable, highly heat-resistant inorganic substance, and capable of preventing the liquid core substance for oozing out from the capsules with the lapse of time.
Conventional process for preparing microcapsules comprising a core of a liquid substance and a outer shell wall of an inorganic substance can be classified roughly into a process wherein precipitation reaction is employed and a process wherein adhesion or forced adhesion of the inorganic wall substance is employed. However, it is difficult to form dense, uniform outer shell walls of capsules by any of those processes. In other words, since the outer wall of the capsule has very small cracks, openings or pin holes and, in addition, the wall is coarse or rough, the liquid core substance enclosed in the capsule is apt to be modified under the influence of the atmosphere such as oxygen, carbon dioxide and water contained in air, or apt to absorb water in air. Thus, the capsule has a defect that the core substance cannot be protected sufficiently stably. Further, if the core substance enclosed in the capsule is a volatile substance, the core substance is vaporized through the outer shell wall of the capsule. If the core substance has a strong smell, the smell is emitted through the outer shell wall of the capsule. if a perfume is used as the core substance, it is hard to protect the same for a long period of time due to vaporization thereof unfavorably.
Thus, according to the known processes for preparing microcapsules having an inorganic wall substance, it is difficult to protect a liquid core substance stably over a long period of time, since not only a chemically unstable substance, volatile substance and hygroscopic substance but also other substances may ooze out from the capsule through small openings of the outer shell wall or these liquid core substances may be influenced by, for example, oxidation by air. Those prior art processes have, therefore, been employed in very limited fields.
In another known process, a liquid substance is charged into a previously formed microballoon comprising a wall of inorganic substance. Such a capsule is prepared by treating the hollow microballoon under a high pressure to form cracks therein and then allowing the liquid substance to be absorbed in the balloon through the cracks. Therefore, the liquid core substance vaporizes or leaks out through the cracks formed in the wall to make it impossible to obtain an ever-stable capsule. Further, there has been attempted a process wherein the wall of inorganic substance is further coated with an organic high polymer substance to prevent the vaporization or leakage of the core substance. However, this coating process inevitably has a defect that superior properties of the micro-balloon, i.e. chemical stability and heat resistance due to the inorganic wall substance, cannot be exhibited sufficiently.

Microcapsules having a wall of inorganic substance and process for the preparation thereof


The invention is directed to a vehicle wheel (1) comprising a fiber reinforced polymer rim (2) for receiving a tire at its radially outer side (3). The rim (2) comprises an outer rim flange (4), an outer rim seat (5), a frusto-conical plane (6) inclined at an angle a relative to the rotational axis (7) of the wheel of between 1 and 90 Q, an inner rim seat (8) and an inner rim flange (9). A wheel hub (10) is connected to the rim (2) via a metal support element (11). The support element (11) is connected with the rim (2) through at least one connecting element (12) which extends through a radially elongated opening (13) in the frusto conical plane (6) of the rim (2) and is received in the support element (11). The support element (11) may alternatively be connected with the rim (2) through at least three connecting elements (12) which extend through radially elongated openings (13) in the support element (11).

One type of conventional wheel comprises a rim for receiving a tire at its radially outer side, wherein the rim comprises an outer rim flange, an outer rim seat, a frusto-conical plane inclined at an angle a relative to the rotational axis of the wheel of between 1° and 90°, an inner rim seat and an inner rim flange. A wheel hub is connected to the rim via a support element, wherein the support element is comprised of metal and wherein the rim is comprised of a fibre reinforced polymer. The support is connected with the rim through at least three connecting elements.
Such a vehicle wheel is described in WO-A-2006/097856. This publication describes a vehicle wheel having a rim made of carbon reinforced epoxy resin and a metal support element. The rim and support element are connected via numerous threaded bolts which extend through a frusto conical plane of the rim and are covered by the tire on one side and by the support element on its other side as shown in FIG. 3 of this publication.
Although the above problems can be resolved as explained a major disadvantage of the design of WO-A-2006/097856 remains. In use the support element can heat up to very high temperatures resulting for example from the heat generated by using the brakes or simply from exposing the wheel assembly to the sun in a hot climate, where it may reach a very high temperature. As a result temperatures variations of 100° C. or more for such a metal support element are not uncommon.
Because the materials of the support element and the rim are different the thermal expansion of the support element and rim will also be different. This can result in a high stress in the wheel assembly and ultimately to failure of the connection between rim and support element or the support elements itself or the wheel rim itself due to the increased stress and resulting fatigue over a period of otherwise normal use.


The present invention provides a contactless flash EPROM array formed in a P-well in a diffused silicon substrate of N-type conductivity. To facilitate a channel erase operation, thin tunnel oxide is formed between the P-well and the overlying polysilicon floating gate EPROM cells. The array is programmed in a conventional EPROM cell array manner. However, in accordance with the invention, the channel erase of a selected row of EPROM cells is accomplished by allowing all bit lines to float, applying a negative erase voltage to the word line of the selected row and holding the substrate at the supply voltage.

1. Field of the Invention
The present invention relates to electrically programmable read only memory (EPROM) devices and, in particular, to a contactless flash EPROM cell array that utilizes a low current channel erase mechanism.
2. Discussion of the Prior Art
FIG. 1 shows a portion of Intel's well-known ETOX EPROM array 10 wherein two ETOX cells 12a and 12b share one drain contact 14. FIG. 2 shows a cross-section of an individual ETOX cell 12 taken along line A--A (i.e. along polysilicon (poly 2) word line 16) in FIG. 1. FIG. 3 shows a cross-section of an ETOX cell 12 taken along line B--B (i.e. along buried N+ bit line 18) in FIG. 1.
The ETOX array 10 is based on the standard "T-shaped" ETOX cell. As shown in FIGS. 2 and 3, the ETOX cell 12 is implemented utilizing a very thin gate oxide 20 (about 100 .ANG.) and graded N+/N- source regions 22 to prevent disturbances due to junction breakdown when the cell 12 is being erased.
As shown in FIG. 4A, the ETOX cell is written in the conventional EPROM manner. That is, hot electrons are injected from the graded source region 22 into the polysilicon (poly1) floating gate 24 when the poly 2 word line 16 and the N+ bit line (drain) 14 are both high.
As shown in FIG. 4B, erasing the ETOX cell 12 is performed by Fowler-Nordheim tunneling of electrons from the floating gate 24 through the thin oxide 20 to the graded source region 22 when the source region 22 is high, the drain 14 is floating and the word line 16 is low. As stated above, the source 22 is graded to prevent junction breakdown during the erase operation.
As discussed by Verma et al., "Reliability Performance of ETOX Based Flash Memories", the programming of flash EPROM cells, such as the above-described ETOX cell, may cause certain cell disturbances. Thus, an important consideration in the design of flash EPROM cells is the proper selection of read and programming voltages in order to minimize these disturbs.
Furthermore, the above-described ETOX array utilizes a cell architecture that requires one drain contact for every two cells in the array. The relatively large size of the contacts places a severe scaling limitation on the array.
U.S. patent application Ser. No. 539,657, filed by Boaz Eitan on Jun. 13, 1990, titled EPROM VIRTUAL GROUND ARRAY, discloses a so-called "contactless" alternate metal virtual ground (AMG) EPROM cell array and its associated process flow. Eitan's AMG concept is attractive because it allows high density EPROMs to be fabricated without using aggressive fabrication technologies and design rules.
As shown in FIGS. 5 and 6, the basic idea of the Eitan array 30 is the use of a "cross-point" EPROM cell that is defined by the crossing of perpendicular poly1 floating gate lines 32 and poly2 word lines 34 in a virtual ground array. To avoid drain turn-on, i.e. electron leakage from unselected cells on the same bit line as a selected cell, metal 36 contacts silicon every two N.sup.+ bit lines 38 to define the drain lines of the array and the non-contacted N.sup.+ bit lines 40 are connected to ground only via access transistors 42 driven by access select lines 44 to define the source lines of the array.
In the Eitan architecture, each drain bit line 38 is contacted only once every 64 cells, each block of 64 cells on the same drain bit line 38 constituting one "segment." Thus, when programming a particular cell in the array 30, only one 64-cell segment need be addressed; all other segments are "off." Therefore, the cells in the unselected segments are not susceptible to leakage.
U.S. patent application Ser. No. 830,938, filed by Albert Bergemont on Feb. 4, 1992, titled ALTERNATE METAL/SOURCE VIRTUAL GROUND FLASH CELL ARRAY, which is commonly-assigned herewith to National Semiconductor Corporation, discloses an AMG flash EPROM array concept.
As shown in FIGS. 7-9, the Bergemont array 50 differs from the Eitan array in two primary aspects. First, alternate N.sup.+ bit lines receive an additional phosphorous implant to provide graded N.sup.+ /N.sup.- source bit lines 52 for the array cells. Furthermore, in a reversal of the Eitan concept, the N.sup.+ /N.sup.- graded source bit lines 52, rather than the N.sup.+ drain bit lines 56, are contacted by metal 54 in segmented fashion; the intermediate node N.sup.+ drain bit lines 56 are noncontacted. As shown in FIG. 8, optionally, the N.sup.+ drain bit lines 56 of the Bergemont array can receive a boron implant to provide N.sup.+ /P.sup.- drain lines 56. The Bergemont array retains the basic "cross-point" cell architecture in that the cells of the array are defined by the perpendicular crossing of poly1 floating gate lines 58 and poly2 word lines 60. Note that, as shown in FIG. 7, the Bergemont cell includes poly1 extensions over field oxide (Fox) in the array in order to achieve a correct coupling from the control gate (i.e. word line 60) to the floating gate 58, particularly in flash applications wherein the thickness of the floating gate oxide is approximately 100.ANG..
The Bergemont architecture facilitates a flash erase mode, wherein an erase voltage is applied to each of the N.sup.+ /N.sup.- source bit lines 52 while both access select lines 62 are held at ground. This causes Fowler-Nordheim tunneling of electrons from the floating gate 58 to the source side 52 of the cell. The graded N.sup.+ /N.sup.- source junction prevents junction breakdown.
The above-described Bergemont AMG flash EPROM array provides a significant advance over the conventional flash ETOX technology by achieving a contactless array. However, like the flash ETOX technology, the double-diffused source lines place a scaling constraint on the effective channel length of the cell.

Method of erasing a high density contactless flash EPROM array


A simulated fabric is produced by heating a substrate having a layer of flocked material so that both the substrate and the flocked material are softened, and applying the surface of a mold, having a finely detailed simulated fabric pattern on it, to the flocked material to plastically deform the flock to a thickness less than the original thickness such that it acquires substantially the same pattern as on the mold surface.

Synthetic simulated fabric materials have become increasingly popular in recent years for employment in applications requiring features such as increased wear and abrasion resistance, durability, moisture resistance, and relatively low cost.
Simulated fabric materials prepared by embossing plastic substrate materials with a fine pattern have been produced. Such materials can be produced to visually resemble a wide variety of fabrics and designs.
Suitable combinations of temperature and pressure conditions, applied to a layer of flocked material which is adhered to a plastic substrate, including foamed substrates, have been proposed to render different appearance characteristics. For instance, it is possible to vary temperature and pressure conditions to provide a simulated fabric having improved color contrast between the substrate and the flocked material.
Mechanical processing steps, such as beating a wetted layer of flocked material on a substrate have been suggested to produce a simulated fabric. It is also possible to apply a layer of flocking material to a substrate, such as a foamed substrate, having a pattern already formed thereon, i.e., a pattern formed beneath the flock layer. Likewise, it is possible to apply flocked material to a substrate to form a predetermined pattern by aligning the fibers in a predetermined orientation while adhering them to a substrate.
It is thus an object of the present invention to provide a relatively inexpensive material that exhibits improved visual and tactile resemblance to a fabric, and that can be easily formed to produce contoured three-dimensional articles having a simulated fabric surface.


The Open Frame Pillow and Head Support System is an apparatus which supports one""s head and/or one""s pillow(s) and head, and is designed with an open frame which has cantilevered upper arms which support its Head/Pillow Rest in a slightly elevated position above the resting or sleeping surface. The frame is intentionally designed to be open at its front side, opposed sides, and rear side. This design allows for one to rest comfortably in a variety of positions lying supine, prone, or on one""s side while allowing for one""s arm or arms to be laid or outstretched in a variety of positions comfortably underneath one""s head, without the weight of the head or the weight of a pillow on which the head is resting, bearing upon the outstretched arm(s) and/or their contiguous body parts such as the shoulder(s), upper arm(s), elbow(s), forearm(s), wrist(s), hand(s). The Head/Pillow Rest can be open in the back to allow for insertion of pillows within it and when made with an elastic material at its bottom portion can support pillows of a variety of different sizes within it. It also supports a pillow on top of it. Portions of the frame can be covered with a Padded Frame Encasement for greater comfort and aesthetics, and a Pillow Slipcover can also be provided to envelop a pillow placed on top of the Head/Pillow Rest so as to contain it to the upper part of the Head/Pillow Rest.

Not Applicable
Not Applicable
Not Applicable
Pillows and head supports as well as devices to help one sleep on one""s side, typically either lay on the resting surface or contain portions of their body or frame which lay on the resting surface which prevent the user from the comfortable placement and movement of the arms underneath the head. Additionally, headrests do not allow for the use of a wide variety of pillows of different sizes and of the user""s choice, and/or two pillows to be used simultaneously as part of its support device.
The Open Frame Pillow and Head Support System is an apparatus which supports one""s head and/or one""s pillow(s) and head, and is designed with an open frame which has cantilevered upper arms. These cantilevered upper arms support the Head/Pillow Rest in a slightly elevated position above the sleeping/resting surface. The frame is intentionally left open in the front, sides, and rear between its upper and lower members so as to allow the user""s arms while lying in either a supine, prone or side position, to be able to be moved and/or placed in a variety of positions underneath the elevated Head/Pillow Rest, while supporting the head and/or a pillow(s) without the weight of the pillow and/or the head bearing on the user""s arm(s) and/or their contiguous body parts.
This open frame design alleviates the discomfort associated with the use of only pillows, where if one sleeps on one""s side for instance, the lower elbow may either be uncomfortably bent in towards the stomach, or the arm may be uncomfortably outstretched putting pressure on the shoulder, or the arm, elbow, wrist, and hand may be placed underneath the pillow(s) where the weight of the head and the weight of the pillow(s) would bear directly upon the outstretched arm(s) and/or their contiguous body parts creating discomfort and cutting off circulation to these body parts.
Additionally, the Head/Pillow Rest can be made with its bottom material/fabric portion consisting of an elastic type material such as Spandex, which allows for a variety of pillows of different sizes to be placed within it. Pillows can also be placed on top of it and can then be covered by the Open Pillow Slipcover whose bottom layer is made of an elastic type material which stretches to envelop a pillow within it and contain it to the upper portion of Head/Pillow Rest. For additional comfort the upper arms of the frame can be padded and the other parts of the frame can be encased by the Padded Frame Encasement.

Open frame pillow and head support system


An apparatus for simultaneously measuring in real time for a reflection-type holographic optical element the wavelength of maximum diffraction efficiency, the angular and spectral selectivities, and the direction of the grating vector by analyzing the characteristics of the intensity distribution of the transmitted beam. A diverging or diffusive beam having an angle of divergence greater than the incident angle satisfying the Bragg condition of the holographic optical element under measurement. The apparatus comprises a multi-wavelength oscillation laser beam source, a beam diffuser, a objective lens, and an image projection screen.

1. Field of the Invention
The present invention relates to holography and, more particularly, to a simple optical apparatus for simultaneously measuring in real time the spectral and angular selectivities, the wavelength of maximum diffraction efficiency, and the direction of the grating vector of a reflection-type holographic optical element.
2. Description of the Related Art
A holographic optical element (HOE) is a hologram that is used to control transmitted light beams, rather than to display images. The angular and spectral selectivities of the HOE represent the deviation of incident angle satisfying the Bragg condition and the deviation of wavelength in the incident angle, respectively. Angular and spectral selectivities are measured, since reflection-type HOEs are used primarily as filters, beam combiner, and image display screens.
A conventional method for measuring angular and spectral selectivities involves measuring the diffraction efficiency for each wavelength or each incident angle by means of an instrument such as a monochrometer, a photodetector, or spectrophotometer. Conventional methods for measuring the angular and spectral selectivities:
(a) require a high-precision rotational or translational stage to control the angle of incidence of the beam incident on the HOE; PA1 (b) require one detector to measure the spectral selectivity and another detector to measure the angular selectivity, because the position of the detector is fixed when the spectral selectivity is measured; PA1 (c) cannot be used to tune an HOE in real-time, since the HOE must be rotated or repositioned after a measurement at a certain position or wavelength, both because the position or wavelength of an incident beam must be varied to measure the angular or spectral selectivity, respectively, and because whether HOE was tuned should be measured while swelling or shrinking its activity by wetting or heating for tuning HOE; PA1 (d) are prone to error, since the beam on which measurements are made is not a collimated beam; and PA1 (e) cannot readily be employed when several grating vectors are present in one HOE.

Apparatus for measuring characteristics of a reflection-type holographic optical element

Korea Institute of Science and Technology


An input buffer circuit is implemented in a compound semiconductor technology such as Gallium Arsenide and converts silicon semiconductor logic levels such as those produced by CMOS and TTL integrated circuits and converts them to logic levels compatible with circuits manufactured in compound semiconductor technology. The input buffer employs a balanced input circuit designed to produce an output voltage representing the switch-point of the compound semiconductor technology when the voltage received from a silicon semiconductor circuit equals the switch-point of the silicon semiconductor circuit. Otherwise, the output voltage of the input buffer is proportional to the difference between the voltage received from the silicon semiconductor circuit and the switch-point of the silicon semiconductor circuit. The balanced input circuit minimizes variations in its output voltage due to variations in power supply voltage, circuit temperature and process parameters. The source-follower configuration of the balanced input also neither sources current to or sinks current from the driving silicon circuit. An output buffer circuit provides a stable high impedance tri-state output in a compound semiconductor technology by eliminating the effects of leakage current common to such technologies. The circuit employs a second pull-down transistor that sinks a small leakage current, thereby positively biasing the source of a first pull-down transistor which turns the first pull-down transistor hard.

The majority of digital electronic circuits in use today are integrated circuits of varying complexity, fabricated in the semiconductor material silicon. Digital circuits are subdivided into logic families corresponding to the interface protocols to which they adhere. The most common of these logic families are TTL (transistor-transistor logic) and ECL (Emitter-coupled logic), which include specifications of power supply forms and input and output signal levels for interfacing with circuits in the same logic family.
In addition to the predominant technology which is based on silicon, other technologies are available for implementing digital integrated circuits. Among these is the compound semiconductor logic based on gallium arsenide (GaAs). GaAs logic is faster than silicon logic and can be used for this reason within silicon logic circuits to achieve great advantages. However, silicon and GaAs logic circuits are characterized by different threshold voltages, which define the interface protocols between logical high states (digital value one) and logical low states (digital value zero). Thus, any composite digital logic system must include input and output buffer circuitry to shift voltage levels between the silicon logic circuits and the GaAs logic circuits, while preserving the corresponding digital value.
FIG. 1 is a block diagram of a typical system for interfacing silicon and compound semiconductor digital logic circuits. A silicon integrated circuit 10 is connected to input buffers 16, which are in turn connected to a compound semiconductor integrated circuit 14. The input buffers 16 transform signals within the silicon logic protocols of the silicon integrated circuit 10 to corresponding input signal levels within the logic protocols of the semiconductor technology of the integrated circuit 14. Output buffers 18, which are connected between the integrated circuit 14 and a silicon integrated circuit 12, then transform the output signals generated by the integrated circuit 14 into corresponding signal levels within the logic protocols of silicon.
FIGS. 2, 3 and 4 depict typical circuits for GaAs input buffers, which are based on MESFETs. These circuits can be classified roughly into two different categories, depending on whether or not a source follower input is used. Each of the depicted circuits exhibit numerous disadvantages, which are discussed below.
The circuits of FIGS. 2 and 3 show examples of the input buffer circuits disclosed in U.S. Pat. No. 4,791,322 to Graham et al., which are based on source follower designs. Depletion mode MESFETs 20, 20a are connected as source followers with their gates serving as buffer inputs 22, 22a and their drains connected to a positive voltage supply V.sub.cc. In FIG. 2, the source of the MESFET 20 has a conduction path to the negative voltage supply V.sub.ss through a diode chain 24 and to a second depletion mode MESFET 26 which is biased into conduction. Similarly, in FIG. 3, the source of MESFET 20a is connected to a negative voltage supply through a diode chain 24a and resistors 28a, 29a.
The input buffer circuits of FIGS. 2 and 3 require positive and negative voltage supplies. Standard semiconductor logic, on the other hand, is based on a single positive supply. As a result, negative voltage supplies must be externally added to any system using these input buffer circuits.
The circuits of FIGS. 2 and 3 rely on the diode chains 24 and 24a, respectively, to shift the voltage level from the driving digital logic circuit to the voltage level corresponding to the same digital value in the protocol of the driven digital logic circuit. Since the actual voltage drop depends on the drop across the individual devices, the shifted voltage level will be sensitive to process and temperature variations in the individual devices. The shifted voltages of the circuits of FIGS. 2 and 3 are also sensitive to the power supply voltages. The input signal threshold voltage of the circuit in FIG. 3 is especially dependent on V.sub.ss. Consequently, the input to the driven digital logic circuit may not switch between low and high states when the output of the digital logic driving the circuit does so.
Finally, the circuit of FIG. 2 is poorly designed to cope with input voltages above V.sub.cc. When input voltages exceed V.sub.cc, the gate-to-drain diode of the MESFET 20 clamps the input at one diode drop above V.sub.cc, i.e. approximately 5.8 volts. However, with the MESFETs 20 and 26 conducting, the path to ground via these MESFETs and the diode chain 24 corresponds to approximately 4 volts, resulting in instabilities in the input. In addition, high input voltages require that the input MESFET 20 be capable of conducting large currents, which increase the likelihood of damage to the device.
FIG. 4 shows an another typical input buffer circuit, which is disclosed in U.S. Pat. No. 4,791,322 to Graham et al. The circuit of FIG. 4 eliminates the additional negative power supplies of the circuits shown in FIGS. 2 and 3, but it also eliminates the high input impedance provided by the source follower input, creating problems of its own. The input 30 is connected to the gate of an enhancement mode MESFET 40 by means of a diode 32, which is reverse biased in the direction of the input signal to the buffer circuit, and two enhancement mode MESFETS 34, 36 connected in series. A depletion mode MESFET 38 has its drain connected to the positive voltage supply, V.sub.cc, and its source connected to its gate and to the gate of the enhancement mode MESFET 40 through a resistor 42.
When the input 30 is taken high by the driving source, the diode 32 prevents any large current flows into the buffer circuit. However, when the input 30 swings low, the circuit sources current into the driving circuit from V.sub.cc via the MESFETs 34, 36, 38, the resistor 42 and the diode 32. The current sinking requirement imposed on the driving circuit by this circuit limits the capability of the driving circuit to drive multiple devices (i.e., limits the fanout of the driving circuit).
The voltage level shift from driving source logic levels to those of the buffer and internal circuitry is achieved by means of two level shifting elements. The first level shifting element is the depletion mode MESFET 38, which sources current across the MESFETs 34 and 36 and is operative for low voltage inputs. The second level shifting element, operative for high inputs, is provided by the drain current through a MESFET 44, which ensures a voltage drop across diodes 46, 48. As with the circuits of FIGS. 2 and 3, discussed above, the dependence of the circuit of FIG. 4 on the MESFET 44 and the diodes 46, 48 for the necessary level shifts makes the output voltage sensitive to process variations in the devices and to operating temperatures of the circuit. In addition, variations in the supply voltage will also effect the output voltage. Also, the circuit of FIG. 4 provides no simple way to adjust the output voltage level for different types of silicon or compound semiconductor logic.
Typical output buffers known in the art present a different set of disadvantages with regard to smooth integration between silicon and compound digital logic. For example, certain typical output buffer circuits require both positive and negative voltage supplies. As discussed above, the negative supply is not standard to silicon based logic and must be supplied externally for these circuits. Additionally, while the advantages of three state functionality are well known in the art, it has not been regularly used in output buffer circuits designed for GaAs for the reasons discussed below.
Three state functionality refers to the capability of putting a circuit's output in a high impedance state in addition to the normal high and low logic states. In this tri-state, the output is disconnected from both the power supply and ground. FIG. 5 shows a typical active high three state buffer 50. This buffer is either enabled to pass a signal from its input 52 to its output 54 or to assert the tri-state at its output 54, depending on whether its enable/disable terminal 56 is high or low.
A barrier to the implementation of tri-state functionality in GaAs technology arises from the relatively low threshold voltage of GaAs enhancement mode devices. Typically, V.sub.th is 0.2 volts. However, worst case process variations may reduce this to 0.15 volts and the temperature dependence of the device may further reduce V.sub.th to as little as 75 millivolts. Thus, in order to fully turn off a MESFET with its source connected to ground, the gate must be pulled reliably below 75 millivolts. A logic input that is not sufficiently low to turn an output MESFET off hard results in sub-threshold leakage current in the channel of the pull-down MESFET, which reduces the output impedance of the circuit in the tri-state.
FIG. 6 illustrates a typical three state output buffer circuit for interfacing compound semiconductor digital logic circuits with silicon digital logic circuits, which is disclosed in U.S. Pat. No. 4,884,563 to MacMillan et al. The output buffer of FIG. 6 incorporates a tri-state input stage 70, three buffer stages 72, 74 and 76, and a standard totem pole output configuration 78. The output configuration 78 is based on MESFETs 80, 82 which pull an output 84 to the corresponding supply rail when turned on.
The output of the tri-state input stage 71 inverts the input level and applies it to the gates of four enhancement mode MESFETs 86, 88, 90, 92. These MESFETS have their sources connected to ground and their drains connected to the drains of MESFETs 98, 100, 102, 104, respectively, on the outputs of the stages 72, 74. Thus, a high voltage level to the tri-state input stage 71, is inverted to low, shutting off the MESFETs 86, 88, 90, 92 and allowing an input 73 of the buffer stage 72 to be passed to the output terminal 84. A low voltage level to the tri-state input stage 71 is inverted by that stage to a high logic state, which is applied to the gates of the MESFETs 86, 88, 90, 92, turning them on. As a result, point A, which is connected to the gate of the MESFET 80, is pulled low, shutting off the pull-up MESFET 80 and isolating the output 84 from the high voltage rail. Similarly, point B is pulled low, shutting off the pull-down MESFET 82.
Since the source of MESFET 82 is at ground, its gate must be pulled below ground to ensure that the MESFET 80 is shut off hard. The circuit of FIG. 6 ensures hard shut off by connecting an on-chip negative charge pump to the source of the depletion mode MESFET 96 via a resistor 97. With the depletion mode MESFET 96 biased into conduction, the negative charge pump ensures that the gate of the MESFET 82 is pulled below ground.
This use of the on-chip negative charge pump to ensure hard shut off of the pull-down MESFET 82 is a severely limited solution to the sub-threshold leakage problem. The charge pump occupies space on the chip and can only provide negative voltage to a limited number of driven outputs, since the current needed from the charge pump for a large number of outputs makes the charge pump circuit prohibitive.

Digital logic output buffer interface for different semiconductor technologies


The preparation of racemic and optically pure tryptophans is described. The D-enantiomers of the 6-substituted compounds possess a potent sweetening capability. Novel intermediates are also disclosed.

Tryptophan, .alpha.-amino-.beta.-indolepropionic acid, is an amino acid originally isolated from enzymatic digests of proteins. Tryptophan can be obtained by extraction, fermentation or chemical synthesis. Extraction is difficult because tryptophan is easily destroyed during acid hydrolysis of proteins, and racemization occurs on alkaline hydrolysis. Fermentative methods for tryptophan production from anthranilic acid or indole have been examined. The synthetic methods are generally of two types (1) syntheses in which the alanyl residue is added to a preformed indole and (2) syntheses in which the indole portion of the molecule is formed late in the sequence. The latter route is preferable, from an industrial point of view, because the indoles are costly raw materials. Furthermore, the latter syntheses involve a minimum of conversions during which the chemically sensitive indole nucleus can be destroyed. On the other hand, the indole formation usually involves cyclization into an aromatic ring leading to mixtures of isomers. The formation of isomers is particularly acute in the case of 4- and 6-substituted tryptophans.
The instant invention provides a means for the obtention, in high yield, of racemic and optically pure tryptophans, the D-enantiomers of which have potential value as non-nutritive sweeters.
Numerous substances have been proposed and/or used as non-nutritive sweetening agents, affording the consumer ingesting the same a sense of sweetness at least desirably comparable to that obtained with natural sugar, but without caloric effect. Such substances are necessary for some persons in order to limit intake of the natural sugars and thereby to control various health conditions, including diabetes. Many of these substances, however, have severe disadvantages. The most frequently encountered disadvantages are a bitter aftertaste and toxic side effects at rates not substantially different from those at which the sweetening effect is obtained. Only two classes of non-nutritive sweetening substances are used to any extent: saccharin-type compounds and cyclamate-type compounds. Both classes have the typical disadvantage of a bitter aftertaste; and in addition, cyclamate-type compounds have only limited activity.
Among the various categories of chemicals which have been evaluated for sweetening effect are the amino acids. A recent publication, Vuataz et al., Experientia, Vol. XXI, pages 692-694, inclusive (1965), reports the evaluation of a number of amino acids, the enantiomorphs being evaluated separately where available. The report shows that while a number of amino acids are sweet in the D form, this is not an absolute correlation. Furthermore, despite the sweet taste of the D-enantiomorph of a given amino acid, the L-enantiomorph of the same amino acid may be bitter. Resolution of the two enantiomorphs of a given amino acid is often difficult. For these various reasons, despite the contribution of Vuataz et al., no amino acid is being used in the sweetening art.
Moreover, throughout the sweetening art, it is well known that there is no correlation between structure and activity, as even relatively small changes in chemical structure often destroy activity.
In recent years the commercially-available synthetic sweetners, saccharin and cyclamate, have encountered some difficulties in toxicological studies. Aftertaste problems have also plagued these products. It has been evident, therefore, that a need exists for new sweetening agents. This need has been met, in part, by the new sweetener 1-aspartyl-1-phenylalanine methyl ester (Aspartame.RTM.), but this dipeptide ester has shown instability under some conditions.
It has recently been discovered that certain substituted tryptophan compounds, in their D form, exhibit a sweet taste of a marked degree, at rates below rates at which any undesirable side effect may be noted. See U.S. Pat. No. 3,899,592 to Suarez et al., the disclosure of which is incorporated herein by reference.
Although it has been found that d,l-tryptophan has a sweetening capability, it is the d-enantiomorph that is the active moiety. Resolution of the d,l-mixture lessens the amount of substance needed for sweetening. Moreover, due to the fact that typically only the l-enantiomorph of amino acids is metabolized by the mammalian body, usage of the d-enantiomorph alone, may be preferred to preclude any opportunity for the mammalian body to incorporate the substance. When, for these or any other reason, it is desired to employ only the d-enantiomorph, resolution of the racemic mixture can be achieved in procedures known in the prior art for the resolution of unsubstituted tryptophan. Three such procedures are discussed and exemplified in detail in Chemistry of the Amino acids, Greenstein et al., vol. 3, page 2341 and following (John Wiley and Sons, Inc., New York, 1961), particular attention is directed to the first two of these (illustrative procedure 39-5 and illustrative procedure 39-6).
It is an object of the instant invention to prepare the aforementioned tryptophans either in the d,l- or the optically active form.


A portable water pumping station is disclosed. A hand-drawn support stand includes wheels, a vertical frame, and a handle that may be used to manually roll the pumping station along the ground. A mounting shelf fixed to the lower portion of the support stand holds a motor-driven water pump. The inlet side of the pump is connected to a suction hose that is either placed into a nearby body of water or connected to a municipal water source. The outlet side of the water pump is connected to one end of a pressure hose. The pressure hose is normally coiled on a storage take-up reel mounted to the frame, and has a nozzle at one end. Additional hose storage frame may be included on the frame for extending the pressure hose if necessary.

When a brush fire threatens an urban residential or business area, there is often very little that the home or business owners can do to protect their property from fire damage. Garden hoses are usually the only available fire fighting tool, and are clearly inadequate for such service. Moreover, often water pressure in municipal water mains is inadequate during such emergencies. Fire fighting forces are often overwhelmed during such emergencies, and cannot be expected to even try to protect every residential or business structure. Thus little is available to assist such property owners during a fire emergency.
During such a fire emergency, structures located near a water source such as a swimming pool or a lake might be saved if there is a readily available means of delivering water from the source to the area to be protected. U.S. Pat. No. 4,671,3 15, issued to Gardner on Jun. 9, 1987, discloses a device suitable for this purpose. However, such a device provides only limited hose storage capability, and thus it provides a relatively small range of protection. Further, such a device is not easily transported by vehicle since it is somewhat bulky in design. Such a device is well suited for transportation in a pick-up truck, or the like, but is not otherwise easily transported.
Clearly, then, there is a need for a portable pumping station that provides high capacity water pumping capability at locations near a water source. Such a needed device would be able to reach difficult-to-reach locations, and would not require electrical power to operate. Such a needed device would conveniently hold multiple water hoses for providing extended range. Further, such a needed device could be readily mounted to a vehicle trailer hitch, or the like, for facilitating transport thereof. The present invention fulfills these needs and provides further related advantages.


An imaging camera includes a housing that defines a proximal end and a distal end. A Fresnel lens is installed in the proximal end of the housing. Moreover, a reflection mode photocathode is installed in the distal end of the housing opposite the Fresnel lens. An electron sensor is disposed in the center of the Fresnel lens. A conductive layer is disposed on the interior of the housing. Further, the Fresnel lens establishes plural concentric optically passive surfaces that are parallel to a central axis defined by the imaging camera. A conductive layer is disposed on each optically passive surface, and an electron lens is established by the conductive layer on the interior of the housing and the conductive layers on the Fresnel lens.

1. Field of the Invention
This invention pertains generally to imaging devices, and more particularly to imaging cameras for detecting ultrahigh energy cosmic rays in space.
2. Description of Related Art
One of the most challenging issues in Astroparticle Physics has been the observation of Extreme Energy Cosmic Rays (EECRs). The existence of particles with energy above ˜5×1019 eV raises fundamental questions about their origin and propagation in space. EECRs have been detected through the Extensive Air Showers (EAS) produced in the Earth Atmosphere. The shower development is accompanied by the emission of fluorescence light in the atmosphere, and in particular, fluorescence light induced in nitrogen with characteristic spectral lines in the ultraviolet (UV) waveband between approximately 300 nm and approximately 400 nm.
Current knowledge of the EECR phenomenon is based on the data of very limited statistics. Planned efforts for the future study of EECRs include ground-based experiments, and experiments in space. Space borne experiments, and in particular the OSS mission Wide-angle Orbiting Lens (OWL), should observe the fluorescence signal in the atmosphere, looking downward from Space at the dark Earth's atmosphere, under ˜60 degree field of view. The fine segmentation and the time resolution of a large camera can allow the reconstruction of the shower arrival direction and energy.
The Extreme Universe Space Observatory (EUSO) is a currently considered space mission that is devoted to the investigation of cosmic rays and downward from Space at the dark Earth's atmosphere, under a 60 degree full filed of view. The fine segmentation and the time resolution of a large camera can allow the reconstruction of the shower arrival direction and energy. EUSO is expected to detect of the order of 103 EECRs of energy E>1020 eV per year, and to open a window into the High Energy neutrino Universe. Current ideas for the design of the camera are essentially based on classical photomultiplier tubes, or hybrid photon detectors. Apart from being heavy and complicated for space applications, such cameras can have other problems, like low quantum efficiency, in particular in the important ultraviolet region, very large dead area around sensitive pixels, non-uniform response, and high cost.
A small number of cosmic rays of extreme energies have been discovered in ground-based experiments. The origin of these cosmic rays presents a complete mystery, since they should not be able to arrive from large distances (due to the interaction with the low-energy photon background), and on the other hand there is no candidate for the "accelerator" of such particles nearby, or in fact, anywhere. A possible solution of this mystery can have a very strong impact on cosmology. The large ground-based experiment "Auger" is dedicated to study this phenomenon. However, much higher event statistics can be achieved by measurements from space. In order to provide for imaging in space, however, a very large (e.g., 3 m in diameter) and very low weight imaging camera is needed.
Current camera designs are based on a very large number (>10,000) of classical photomultiplier tubes (PMT) arranged in the focal surface of a large Fresnel lens system. Although in principle feasible, this concept is hampered by numerous weaknesses. Apart from the large mass and immense constructional complexity, such cameras can have an important scientific drawback, e.g., low sensitivity, and consequently relatively high detection threshold energy, and poor energy resolution. Other drawbacks include very low quantum efficiency (in particular in the important ultraviolet region), very large dead area around the sensitive pixels, and very high cost. It happens that PMTs present the main source of these problems.
For example, FIG. 1 is a schematic diagram of an imaging electron lens, generally designated 10, that uses a transmission-mode photocathode according to a design which is described in D. Ferenc, Imaging Hybrid Photon Detectors with Minimized Dead Area and Protection Against Positive Ion Feedback, Nucl. Instr. and Meth. A431(1999) pp. 460-475, incorporated herein by reference.
As shown in FIG. 1, the electron lens 10 defines a central axis 12. A generally curved glass window 14 and an electron sensor 16 are placed along the central axis 12 at a predetermined distance from each other. FIG. 1 shows plural focusing electrodes 18 between the photocathode 14 and the electron sensor 16. Moreover, a photocathode layer 20 is disposed on the glass window. FIG. 1 further shows a first electron trajectory 22, a second electron trajectory 24, a third electron trajectory 26, a fourth electron trajectory 28, a fifth electron trajectory 30, and a sixth electron trajectory 32 within the electron lens 10. It is to be understood that these electron trajectories 22, 24, 26, 28, 30, 32 correspond to an angular spread of ±45 degrees, at an electron energy of 1 eV. It can be appreciated that light 34 can reach the photocathode 14, e.g., from the left looking at FIG. 1 and can cause the photocathode 14 to emit photoelectrons. In turn, the photoelectrons emerging from the photocathode 14 can be focused by the electron lens 18 to the electron sensor 16.
It will be appreciated that non-imaging photosensors based on a reflection-mode photocathode exist, e.g., the non-imaging reflection-mode ReFerence photosensor (see, D. Ferenc, A Novel Photosensor Concept, Nucl. Instr. and Meth. A 471 (2002) p. 229, incorporated herein by reference; D. Ferenc et al., First ReFerence photosensor prototype, Nucl. Instr. and Meth. A 504 (2003) pp. 359-363, incorporated herein by reference). However, so far no imaging phototubes based on a reflection-mode photocathode exist, with the exception of the Blind-HPD in which a blind resembling a Venetian blind is attached to the entrance window of the tube (see, D. Ferenc, Imaging Hybrid Photon Detectors with a Reflective Photocathode, Nucl. Instr. and Meth. A 442 (2000) pp. 150-153, incorporated herein by reference). That design offers good imaging quality, but has only very limited application due to its narrow angular acceptance and wide time jitter.
It will also be appreciated that an imaging electron lens based on a reflection-mode photocathode is problematic in general because the photoelectrons must move in the opposite direction from the incoming light, which requires the focusing electrodes and the position-sensitive electron sensor to reside upstream from the photocathode. This in turn leads to an unacceptable but apparently inevitable optical obstruction of the photocathode.
FIG. 2, for example, shows one such imaging electron lens, generally designated 50, that uses a reflection-mode photocathode. As shown in FIG. 2, the electron lens 50 defines a central axis 52. A non-transparent, generally curved substrate 54 and an electron sensor 56 are placed along the central axis 52 at a predetermined distance from each other. FIG. 2 shows plural focusing electrodes 58 placed between the substrate 54 and the electron sensor 56. Moreover, as shown in FIG. 2, a photocathode layer 60 is disposed on the substrate 54.
FIG. 2 further shows a first electron trajectory 62, a second electron trajectory 64, a third electron trajectory 66, a fourth electron trajectory 68, a fifth electron trajectory 70, and a sixth electron trajectory 72 within the electron lens 50. It can be appreciated that light 74 can reach the photocathode 54, e.g., from the left looking at FIG. 2 and can cause the photocathode 54 to emit photoelectrons. In turn, the photoelectrons emerging from the photocathode 54 can be focused by the electron lens 58 to the electron sensor 56. Unfortunately, it can be quickly appreciated that, in this configuration, the electron sensor 56 and the electron lens 58 block a substantial portion of the light 74 before it reaches the photocathode 54.
Therefore, there is a need for a very high sensitivity (quantum efficiency), single-photon resolution, fast response, minimum dead area, unique constructional simplicity, and extremely low weight camera. The present invention satisfies that need, as well as others.

Highly sensitive imaging camera for space applications including detection of ultrahigh energy cosmic rays

The Regents of the University of California


A viewer for inspecting the condition of an end face of an optical fiber which has been cleaved, while the fiber is still in the cleaving device. The viewer takes the form of a pocket-type microscope having a cylindrical body with an eyepiece at one end and an objective lens at the other end, and an adaptor at the end of the body having the objective lens. The adaptor has a plurality of legs having notches therein forming seats which are specially adapted to be mounted on fiber-supporting pads of the cleaver. The adaptor is removable from the body so that different adaptors may be used for different cleavers. The body fits in a socket of the adaptor which may be disposed at an angle with respect to the legs to allow oblique viewing of the fiber end face while it is still in the cleaver. The viewer may optionally be used with an inspection tray having a trunnion at one end, the adaptor of the viewer being designed to pivotally mount to the trunnion, allowing viewing of the fiber end face at any angle.

1. Field of the Invention
The present invention generally relates to optical viewing devices, and more particularly to a device which is used to inspect the end faces of cleaved optical fibers.
2. Description of the Prior Art
The use of optical fibers for high speed communication and data transmission via optical signals has become well established. It is often necessary to splice an intermediate portion of optical fiber, due to breakage of the fiber, or to connect a terminal end of a fiber to another fiber in order to reach very distant locations. The condition of the fiber end face is important since irregularities in the surface of the end face may result in higher signal loss across the splice. With some optical connectors, such as biconic and ferrule connectors, the condition of the end faces may be inconsequential, since the end faces are typically (but not always) smoothed in a polishing operation. See, e.g., U.S. Pat. No. 3,902,784 issued to Dakss et al. For mechanical and fusion splices, however, a cleaving operation can often produce a smooth end face without the complicated polishing step. Moreover, it would be more difficult to polish the end faces of fibers which are to be connected via a mechanical or fusion splice, since there is no structure inherent in such splices (like a ferrule) which serves to hold the terminal end of the fiber.
In the cleaving operation, which typically requires special cleaving devices having strict mechanical tolerances, a score line is produced along the outer surface of a fiber, and the fiber is then bent or pulled over a form, causing it to break at the score line. Unfortunately, these devices do not always provide a perfect cleave, i.e., the end faces may possess unacceptable defects such as irregular cracks, lips, or shattered ends, and the operation must be repeated. The operation is further complicated by the fact that the fibers must be removed from the cleaver and placed in another device before the end faces of the fibers can be inspected. For example, U.S. Pat. No. 4,671,629 depicts a device which is used to examine the surface finish of fiber optic ends. This device is rather cumbersome in that it requires access to both ends of the optical fiber. Alternatively, a pocket-type microscope, such as the one sold by FOTEC of Japan under model number V100, may be used to view the fibers. That device includes a light attachment which swivels away from the main microscope body to illuminate the object viewed from an angle, but the microscope uses plastic lenses which have poor optical properties, and is not well-suited for inspecting bare fibers. Finally, expensive interferometers may be used to inspect the end faces. All of the prior art devices, however, still require removal of the fibers from the cleaver prior to inspection. It would, therefore, be desirable and advantageous to devise an instrument for visually inspecting the end face of a cleaved fiber while it is still in the cleaver. In this manner, the cleaved end faces may be checked more quickly.

Minnesota Mining and Manufacturing Company


A printed circuit board apparatus includes a handle which has an extension plate which extends into an optical switch so as to prevent communication between an optical emitter and optical receiver. To remove the printed circuit board apparatus from its associated rack housing, rotation of the handle is first required which moves the plate and which causes the detector to go HIGH and signal to a telecommunications system that the board is soon to be removed so that a graceful switch can be made from that board to a redundant copy thereof. The printed circuit board apparatus further includes a deflectable lever which contacts to ground the rack housing upon inserting the printed circuit board apparatus into its associated rack housing so as to provide electrostatic discharge protection. The apparatus further includes a face plate which has a generic configuration so as to potentially accommodate any user interface permutation required by any printed circuit board to be inserted into the housing, with application specific labels being applied to each face plate to cover up any holes not providing any user interface information to a craftsperson for the associated printed circuit board. An electromagnetic interference gasket shield is also provided around a circumference of each printed circuit board assembly located in the rack housing.

The present invention relates to an improved printed circuit board apparatus, and in particular to an improved face plate assembly for varying kinds of printed circuit boards which are to be mounted in a rack housing.
It is common in the telecommunications field to have rack housings which are intended to accommodate a plurality of printed circuit board assemblies therein, each assembly being mounted in the rack housing by sliding it inward so as to be parallel and closely adjacent to other printed circuit boards. Each circuit board has a plurality of electrical pins extending from its back end which commonly engage a like plurality of housing pin contacts, and through these pins and contacts signals pass so that integrated circuits and other electronic elements on the printed circuit boards can send and receive signals to and from other electronic components either situated within the particular rack housing in question or other electronic components electrically connected to the pin contacts of the rack housing.
Presently available printed circuit board assemblies suffer from a plurality of disadvantages. First, numerous printed circuit boards used in the telecommunications industry in particular are deemed to perform critical functions, and as such at least one redundant board is generally provided for each critical board so that in the event one of these critical boards fails the telecommunications system served by the critical board automatically switches over to the redundant board and thereafter utilizes the redundant board to perform operations required thereby so that system failure is prevented. With such critical boards, it is common to provide a manual switch on a face plate of the critical board which can be toggled prior to removing the critical board for inspection or other required work. Upon toggling of the switch, the critical board, which is in its active mode, is disabled and replaced by the redundant board in what is commonly known as a graceful transition by electronics associated with the telecommunications system. Such graceful transitions generally are made at a convenient processing time for microprocessors associated with the telecommunications system, for example at the end of an information frame or superframe, as opposed to instantaneously within the middle of a frame and possibly even in the middle of a packet or byte contained in the frame. Commonly, numerous graceful transition instants occur each second. A disadvantage with such face plates is that oftentimes a craftsperson forgets to activate the switch prior to removing an active critical board whereby the telecommunications system is forced to enter its failure switching mode which, if occurring at an inconvenient instant, can result in lost data, lost data cycling efficiency, and false system alarms.
Printed circuit board assemblies also have to guard against electrostatic discharges which can be caused by static electricity associated with a board being inserted into a rack housing and/or static electricity on a craftsperson handling the board when inserting it into a rack housing. A common construction for guarding against electrostatic discharge is to provide an elongated grounding pin at the back of the printed circuit board which makes contact with the rack housing prior to any signaling pins associated with the printed circuit board, with the elongated pin thereby discharging any undesired electrostatic charges present to ground via the rack housing. This design solution is relatively expensive.
Finally, any rack housing which accommodates several boards, such as 10-20 boards or more, necessarily houses boards having different functions and boards which require different user interfaces such as varying unique arrangement of lights on a face plate thereof for communicating information to a craftsperson such as power ON, power OFF, unique component failures, etc. Individually machining each face plate to accommodate its unique user interface design tends to be inefficient and costly.

Printed circuit board apparatus with optical switching


A circuit provides a power regulation loop that operates in two modes and uses a single comparator between the two modes. One mode, an open mode, involves generating an overload signal when the pass transistor is in an oversaturated mode indicating that the voltage drop of the device exceeds a predetermined threshold. The other mode, a linear mode, involves generating an optimal value sense resistor for a liner mode operation of a pass transistor. The two modes do not exist simultaneously and, therefore, a single comparator may be used between the two modes.

In the electronics industry, there is a need for regulating current. Many battery powered electronic devices include components for monitoring the current to and from a load, such as a battery pack. This is typically done by putting a sense resistor in the path between the battery pack and the load and also between the charging unit and the battery pack. A regulating circuit then measures the voltage across the sense resistors and limits the current to or from the battery pack accordingly. This limiting is typically performed by using a transistor in the current path from the battery pack to the load or charging unit and by causing the transistor's control terminal to be driven in response to the voltage across the sense resistor.
A transistor exhibits low resistance when its control terminal is held at a voltage appropriate to turn the transistor "full on." In current regulating circuitry, this is often accomplished through the use of an amplifier coupled to the sense resistor with the amplifier output driving the control terminal of the transistor. With the appropriate choice of sense resistor and amplifier characteristics, the current regulating circuitry can be constructed such that for currents less than a regulation current limit, the amplifier drives the control terminal of the transistor to a full on state. As current through the sense resistor increases above the regulation current limit, the amplifier drives the control terminal of the transistor to reduce the current to the regulation current limit. This has the effect of providing little resistance when current passing through the regulating circuitry is less than the regulation current limit and provides the appropriate amount of resistance through the transistor to limit the current to the regulation current when a load tries to draw an excess amount of current.

Power regulation loop performs two functions


A breakdown piano is disclosed which incorporates, in the preferred and illustrated embodiment, a separable keyboard with hammer mechanism attached which slidably removes from the body of the piano. The remainder of the piano apparatus is incorporated with the body. This is an aid to reduction of weight and division of the piano into two more readily manageable packages for quick moves. The apparatus incorporates a slide assembly aligning the keyboard, a clamp to latch the hammers in a fixed position when detached from the body and a latch release mechanism. There is, additionally, means for bolting the piano keyboard to the body.

A piano is a very popular instrument with small instrumental groups. It is a device which has substantial bulk and weight as a result of its size. With small traveling musical entertainment groups, the piano must, nevertheless, be moved from engagement to engagement. This is difficult to accomplish as a result of the size, weight and bulk of a piano. In particular, the weight is such, when coupled with its shape, the apparatus is very difficult to handle by even strong workers. This is true both of standard percussion piano instruments and electronic keyboard instruments.
The piano has a specified length at the keyboard, but, other than this, the shape and profile of a piano may vary. They commonly fall into two categories, the upright or grand piano type constructions. The present invention is an apparatus which particularly enables the grand piano type construction to be utilized, although it is also adapted for incorporation in an upright piano construction. Through the use of the present invention, a single piano, perhaps weighing 300 to 400 pounds, is divided into two packages. One package will incorporate the bulk of the body, but is reduced notably in weight. The precise change in weight depends on the particular construction of piano involved, particularly whether it has heavy wooden frame members or a cast iron frame. Without regard to the details of its construction, the piano body, itself, is markedly lighter as a result of removal of the keyboard and all of the apparatus affixed to the back side of the keyboard.
The present invention thus divides the piano into two separate packages. It particularly protects the rather delicate construction found in the keyboard area. The keyboard, itself, is connected by suitable levers to a piano striker mechanism. The striker mechanism includes pivoted hammers which are padded around the head of the hammer with a felt covering. The keyboard, when removed, incorporates apparatus which clamps the hammers against loose movement, thereby protecting the nest of hammers. Presumably, eighty-eight hammers are ordinarily included inasmuch as this is the customary configuration of a piano.
The present apparatus divides a piano for quick assembly or knockdown. It yields two separate assemblies which can travel quite easily. Moreover, it yields a body of reduced weight which can be more readily handled by two workmen. By contrast, two workmen can hardly handle a fully assembled, complete piano with all components. The keyboard assembly, when removed, is able to be handled quite easily. Indeed, it can be removed and set in a generally rectangular storage box or cabinet for protection. At the time of disassembly or reassembly, the equipment goes together quite readily.


A burner assembly includes a register having a circular front wall and an annular side wall; a plurality of cylindrical bluff body elements circumferentially spaced about the annular side wall in a plurality of axially spaced rows for supplying air to the register; fuel supply assemblies which supply at least one of coal, gas and oil to the register for mixing with the air; and a plurality of bluff body discs, each positioned within a respective bluff body element for increasing the velocity and pressure drop of the air entering the register so as to enhance mixing of the fuel and the air within the register, and to reduce the NOx.

This invention relates generally to burner assemblies and, more particularly, is directed to a register for a burner assembly.
Burner assemblies in which gas, oil, coal and other combustible materials are mixed with air are well known in the art. Such burner assemblies are generally associated with industrial boilers and furnaces, and comprise a structure known as a register which is usually mounted at the base of the furnace or boiler, and which contains appropriate fuel and air inlets, and houses the burner gun that serves to ignite the fuel. Thus, the combustible material, such as oil, coal and gas, enters the register through appropriate inlets formed in the register. In order to provide efficient mixing of the air with the fuel, a plurality of entry ports are generally positioned within the annular side wall of the register, such that the air impacts the combustible material at an angle thereto so as to provide enhanced mixing. Additionally, the entry ports within the annular side wall may be inclined so as to provide a tangential spin to the air supplied to the register.
With such conventional arrangement, the problem of adequate mixing of the air with the combustible material still remains. In other words, it is still desirable to obtain more effecient and effective mixing of the air and fuel.
Related to this problem of inadequate air balance, that is, inadequate mixing of the fuel and air, there is the problem of reducing nitrous oxides (hereinafter referred to as NOx), resulting from oxidation of nitrogen in the air, which, in turn reduces the flame retention, thereby providing for lowered radiation.
As discussed in U.S. Pat. No. 4,297,093, various methods have been used for suppressing the generation of NOx, such as reduction of the flame temperature, reduction of oxygen concentration in the combustion zone and shortening of the stay time of the combustion gas in the combustion zone of high temperature. However, as described therein, the adoption of these techniques also poses various problems concerning stability of the flame, emission of unburnt substances and smoke, responsive characteristic to the fluctuation of load, thermal efficiency, the cost of modification of the boiler, increase of the fuel consumption, and the like. U.S. Pat. No. 4,297,093 discloses an arrangement for reducing NOx by utilizing a swirler to provide a small scale of turbulence to the combustion air. The swirler is located in the vicinity of the fuel injection port.
Related to the turbulence discussed above, it is known that the flow velocity of a combustible mixture is reduced when an obstacle is placed in the flow path thereof. Accordingly, the chances for the flame speed to match the flow velocity at some region in the flow field, a requirement of flame stabilization, are improved. If the obstacle is a bluff body, that is, a non-streamlined body, as the fluid is accelerated, a flow velocity is reached where the adverse pressure gradient downstream from the obstacle is strong enough to set up a recirculating vortex system in the wake of the bluff body, as taught by Combustion Aerodynamics, J. M. Beer and N. A. Chigier, Halsted Press Division, John Wiley and Sons, Inc., New York, pages 68 and 73.


A subscription update method, device, and system, where the method is performed by a first event notification network element and includes: determining that a notification condition of a first subscription event of a first terminal is met; obtaining first callback address information of a target subscription network element; and sending a first message to the target subscription network element based on the first callback address information, where the first message carries an identifier of the first terminal and a first event notification of the first subscription event, and the identifier of the first terminal is used to correlate the first event notification with the first terminal.

In some approaches, an access and mobility management function (AMF) network element serving a terminal may subscribe, according to a requirement, to an event related to the terminal from an event notification network element such as a session management function (SMF) network element, a unified data management (UDM) network element, or a policy control function (PCF) network element. When subscribing to an event, the AMF network element sends a subscription request to the event notification network element. The subscription request carries subscription information, related to the terminal, of the AMF network element, for example, information about a subscription event of the terminal, callback address information, related to the subscription event, of the AMF network element, and a notification correlation identity (ID) allocated by the AMF network element to the subscription event. Further, the event notification network element sends a subscription response to the AMF network element. The subscription response carries a subscription correlation ID allocated by the event notification network element to the subscription event, and the like. In this case, when a notification condition of the subscription event is met, the event notification network element sends, based on the callback address information, related to the terminal, of the AMF network element, an event notification and the notification correlation identity to the AMF network element that has subscribed to the event. The AMF network element correlates the event notification with the subscription event based on the notification correlation identity.
In addition, in some approaches, in a scenario in which a terminal has migrated from a source AMF network element to a target AMF network element, because an event notification network element still stores subscription information, related to the terminal, of the source AMF network element when a notification condition of a subscription event is met, the event notification network element still sends an event notification of the subscription event to a source subscription network element based on the stored subscription information, related to the terminal, of the source AMF network element. As a result, a target subscription network element currently serving the terminal cannot learn the event notification of the subscription event in a timely manner, and therefore cannot process the corresponding subscription event in a timely manner.
Therefore, how to perform a subscription update such that a target subscription network element can learn an event notification of a subscription event in a timely manner in a scenario in which a terminal has migrated from a source subscription network element to the target subscription network element is a problem that needs to be urgently resolved currently.

Subscription update method, device, and system


A network appliance may include a signal splitter that splits an incoming signal into multiple portions. The signal splitter can direct one portion of the incoming signal to a switching fabric and another portion of the incoming signal to an optical switch. By monitoring the power intensity of the portion of the incoming signal received by the switching fabric, the network appliance can seamlessly switch between a bypass traffic path and a pass-through traffic path without losing network traffic caused by gaps in network connectivity. Such a configuration also enables the network appliance to maintain an accurate record of the logical connectivity state even when the network appliance is in the bypass state (i.e., when network traffic bypasses the switching fabric of the network appliance).

Traffic in a computer network can be analyzed to improve real-time decision making for network operations, security techniques, etc. The traffic may be acquired at numerous entry points by a variety of devices and/or applications (collectively referred to as "nodes" in the computer network) to provide extensive visibility of traffic flow and network security. Given the complexity and volume of traffic routed through many infrastructures, the traffic is often routed through one or more network appliances that are connected to various kinds of network tools. Examples of such network tools include an intrusion detection system (IDS) and an intrusion prevention system (IPS).
A network appliance can operate as an in-band (i.e., "inline") device or an out-of-band device. Out-of-band devices operate outside of the path of data traffic between an origination node and a destination node and receive copies of the data packets that make up the traffic, rather than the original data packets. Out-of-band devices are able to freely modify the copies of the data packets because the original data packets are allowed to traverse the network unimpeded. Inline devices, on the other hand, operate within the path of data traffic between an origination node and a destination node and receive and forward the original data packets.
Because inline network appliances reside within the path of data traffic, connectivity issues affecting inline network appliances can degrade the functionality of the computer network as a whole. For example, the path of data traffic may collapse if an inline network appliance loses power. Consequently, many inline network appliances are configured to switch between a pass-through mode and a bypass mode. However, when an inline network appliance switches from bypass mode to pass-through mode, the path of data traffic is momentarily disrupted, such that network traffic is irrecoverably lost.

Reduction of network connectivity gaps experienced by inline network appliances


A multi-carrier spread spectrum (MC-SS) technique is disclosed which includes non-linearly modifying the sub-carriers in the receiver. A method (600) and receiver (200, 300) for processing an MC-SS signal, a transceiver for MC-SS communications (700), and an MC-SS radar (800) are describe.

1. Field of the Invention
The present invention relates generally to multi-carrier spread spectrum communications.
2. Related Art
Spread spectrum (SS) systems have proven useful in a variety of applications, including wired and wireless communications, ranging, radar, and synchronization. All of these applications may suffer from interference that is ameliorated by the use of SS techniques. SS operates by greatly expanding the frequency spectrum of the information-containing signal. This expansion is controlled by a spreading code. For example, in direct sequence spread spectrum (DS-SS) the information signal is multiplied by a high rate spreading code. The high rate spreading code creates the wide bandwidth transmit signal. Multi-carrier spread spectrum (MC-SS) is an alternative to the conventional DS-SS and frequency hopping spread spectrum (FH-SS) techniques. MC-SS provides a number of distinct advantages over conventional SS. For example, U.S. Pat. No. 5,521,937 issued to Kondo et al. discloses a MC-SS system having resistance to multipath fading and narrow-band interference. MC-SS systems can also provide improved resistance to partial-band interference and jamming.
The improved performance of MC-SS over conventional SS is obtained by transmitting each symbol simultaneously across several sub-carrier bands, where the signal on each sub-carrier band is a conventional (although possibly lower bandwidth) spread spectrum signal. At the receiver, the signals from each sub-carrier band are processed and combined. It is difficult to combine the sub-carriers and maintain good performance, since the optimum weighting of the sub-carriers depends on the per sub-channel channel gain, interference/jamming statistics, and noise statistics. For example, U.S. Pat. No. 5,521,937 discloses a maximum ratio combiner (MRC). The MRC combines the sub-carriers by estimating the signal to noise ratio (SNR) on each sub-carrier band, linearly scaling the signal from each sub-carrier band proportionally to the SNR of that sub-carrier band, and then summing all the channels. The MRC combiner must, however, estimate the SNR for each sub-carrier band. Any errors in the estimate of the SNR result in degradation of performance relative to an optimal receiver. Accurate estimation of SNR has proven difficult to achieve in practical systems.

Multi-carrier spread spectrum using non-linear modification of sub-carrier bands


A magnetic disk jacket having, disposed on an internal surface of a jacket frame, a liner for cleaning a magnetic disk, wherein the liner comprises 0.03-0.5 g per kg of said liner of a modified straight chain type polydimethylsiloxane having in each molecule thereof at least one group selected from the group consisting of hydroxyl, amino, mercapto, carboxyl, .alpha.-methylstyrene group, .alpha.-olefin group, fluorine, alkyl, higher fatty acid group, methacrylic group, acrylic group, polyether group and epoxy group, said modified straight chain type polydimethylsiloxane having a viscosity of from 50 to 3000 cSt at a temperature of 25.degree. C.

1. Field of the Invention
The present invention relates to a magnetic disk jacket. More particularly, the present invention is concerned with a magnetic disk jacket having a liner with an increased dust collecting capability to thereby improve the efficiency of cleaning the magnetic disk.
2. Description of the Prior Art
A conventional magnetic disk jacket has a structure in which a liner for cleaning a magnetic disk is disposed on an internal surface of a jacket frame.
With respect to such a liner, the extent of swelling thereof is appropriately controlled, depending on the condition of fusion thereof to the internal surface of the jacket frame, to thereby improve cleaning efficiency and avoid regeneration of dust or the like collected with the liner.
In the case of a magnetic disk jacket for 3.5-inch magnetic disks, a lifter is disposed between the liner and the internal surface of the jacket frame, whereby the liner is partially swelled toward the surface of the magnetic disk so that the swelled portion of the liner is used for cleaning the surface of the magnetic disk.
However, in the conventional magnetic disk jacket, the means for cleaning the magnetic disk have been limited to the extent of control of swelling of the liner so as to improve cleaning efficiency, and to the conditioning of the fusion pattern of the liner to the internal surface of the jacket frame so as to prevent generation of dust or the like included in the liner. Thus the improvement in cleaning performance by these measures has been successful only to a limited extent. Moreover, various types of treatments are incorporated into the liner material, which causes a problem wherein the treatments migrate into the surface portion of a rotating magnetic disk to thereby raise the coefficient of dynamic friction between the liner and the magnetic disk.


The present invention relates to a needle curving apparatus for curving one needle or a multiplicity of needles simultaneously. The apparatus includes a curving system for bending the needle and a reciprocating drive system for biasing the needle blanks against the curving system and reciprocally moving the needle blanks to form the curved needle.

1. Field of the Invention
The present invention relates to needle curving devices. More particularly, the invention relates to a reciprocating needle curving device for curving one needle or a multiplicity of needles simultaneously.
2. Description of the Related Art
The production of needles involves many processes and different types of machinery in order to prepare quality needles from raw stock. These varying processes and machinery become more critical in the preparation of surgical needles where the environment of intended use is in humans or animals. Some of the processes involved in the production of surgical grade needles include, inter alia: straightening spooled wire stock, cutting needle blanks from raw stock, tapering or grinding points on one end of the blank, providing a bore for receiving suture thread at the other end of the blank, flat pressing a portion of the needle barrel to facilitate easier grasping by surgical instrumentation, and curving the needle where curved needles are desired. Conventional needle processing is, in large part, a labor intensive operation requiring highly skilled workmen. Generally, extreme care must be taken to ensure that only the intended working of the needle is performed and the other parts of the needle remain undisturbed.
Curved needles have advantages over other needle configurations in many surgical procedures for a variety of reasons including, uniformity of entry depth for multiple sutures and proper "bite" of tissue surrounding the incision or wound. When providing curved needles for surgical procedures it is desirable for the needles to have a specified curvature, i.e., a predetermined radius of curvature. The predetermined radius of curvature for the needle varies with specific applications.
Conventional needle curving techniques create the curve by manually bending the machined needle around an anvil structure having a desired curvature. To attain the desired needle configuration, the anvil structure provides a shaping surface for deforming the needle. Typically, the needle is positioned for curving by manually placing the needle for engagement with the anvil structure and holding it in place by a holding device. The needle is subsequently bent by manually manipulating the holding device so the needle curvature is formed about the shaping surface of the anvil structure.
When needles are made of steel or similar resilient materials, the anvil or mandrel used should have a smaller radius than the radius desired in the final needle. This configuration allows for some springback after the bending operation and ensures that the desired radius of curvature is attained. A disclosure of such features may be found in, for example, U.S. Pat. No. 4,534,771 to McGregor et al.
One disadvantage to conventional needle curving techniques is that only one needle can be curved around an anvil structure at a time. Another disadvantage is that the needle is manually positioned for engagement about the anvil surface. Lastly, the incidence of needle damage during the curving process is relatively high due to the manual placement and bending of the needle.
Therefore a need exists for a needle curving device that is capable of simultaneously curving a multiplicity of needles or curving a single needle without the high incidence of needle damage. It is also desirable to provide a needle curving device which cooperates with a needle holding fixture for positioning one or more needles for curving so as to increase the production rate of the suture manufacturing process.


Magnetic arrangement for transporting magnetized material, comprising a device for conveying a magnet arrangement for transporting magnetized material and a magnetized material separating device having an improved configuration of a magnet arrangement.

Processes and apparatuses for separating magnetic constituents from a dispersion which dispersion comprises magnetic constituents and non-magnetic constituents are used for a separation of ore from gangue.
For this purpose, a raw material to be separated is prepared beforehand, in that ore particles are converted into magnetic constituents. Gangue particles are provided as non-magnetic constituents. This can be reached by attaching magnetic particles to ore particles, wherein gangue particles are not attached to magnetic particles. Having provided the ore particles with magnetic properties, it is possible to separate ore particles from gangue by applying a magnetic field.
The raw material comprises ore and gangue, and after preparation comprises magnetic constituents and non-magnetic constituents. Magnetic constituents and non-magnetic constituents are brought into dispersion, so that the resulting dispersion may be forced into a flow process. The flow process allows an efficient separation process.
Processes and apparatuses for separating magnetic constituents are for example known from US 2011/1686178 A1, WO 2012/104292 A1, US 2011/0174710 A1, or U.S. Pat. No. 4,946,590 A.
US 2011/1686178 A1 describes a device for separating ferromagnetic particles from a suspension, wherein the device has a tubular reactor and a plurality of magnets which are arranged outside the reactor, wherein the magnets being movable along at least part of the length of the reactor up to the vicinity of a particle extractor by means of a rotary conveyer.
WO 2012/104292 A1 describes an apparatus for separation of magnetic constituents from a dispersion, having at least one loop-like canal through which a dispersion flows having at least two inlets and at least two outlets, wherein at least one magnet is moveable alongside the canal, wherein the canal is arranged relative to gravity in a way that non-magnetic constituents are assisted to go into at least one of the first outlet by sedimentation, and by current of the dispersion, and magnetic constituents are forced into at least one second outlet by magnetic force against a current of flushing water.
US 2011/0174710 A1 describes a separating device for separating magnetizable particles and non-magnetizable particles transported in a suspension flowing through a separating channel, having at least one permanent magnet arranged on at least one side of the separating channel for producing a magnetic field which deflects magnetizable particles to the side, wherein in addition to the permanent magnet at least one coil is provided for producing an additional field.
U.S. Pat. No. 4,946,590 A describes a clamp on magnetic water treatment device, which can be fixedly clamped on a water conduit.

Magnet arrangement for transporting magnetized material


The present technology discloses processes for producing carboxylic acid. In some embodiments, the processes include contacting methanol and carbon monoxide in the presence of a liquid reaction medium under carbonylation conditions sufficient to form a carbonylation product, including acetic acid and acetaldehyde. The liquid reaction medium may include a carbonylation catalyst selected from rhodium catalysts, iridium catalysts and palladium catalysts; and water in a water concentration in a range of 1 wt. % to 14 wt. % based on the total weight of the liquid reaction medium. In certain embodiments, the processes comprise contacting at least a portion of the carbonylation product or a derivative thereof with a micro-porous material such as a silicoaluminophosphate (SAPO) to selectively convert at least a portion of the acetaldehyde to crotonaldehyde.

This section introduces information from the art that may be related to or provide context for some aspects of the techniques described herein and/or claimed below. This information is background facilitating a better understanding of that which is disclosed herein. Such background may include a discussion of "related" art. That such art is related in no way implies that it is also "prior" art. The related art may or may not be prior art. The discussion is to be read in this light, and not as admissions of prior art.
Carboxylic acids, such as acetic acid, may be commercially produced by alcohol carbonylation. Unfortunately, carbonylation processes often create by-products, which can be detrimental both to the process at hand, as well as subsequent processes. Significant energy has been devoted to removal of such by-products, including a variety of processes and techniques. However, such processes and techniques can be difficult and costly. The present disclosure provides for processes and related embodiments directed to resolving, or at least reducing, the challenges outlined herein.

This patent is subject to a terminal disclaimer.

Removal of aldehydes in acetic acid production processes