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Improved method for removing metal vapor from gas streams

Description: This invention relates to a process for gas cleanup to remove one or more metallic contaminants present as vapor. More particularly, the invention relates to a gas cleanup process using mass transfer to control the saturation levels such that essentially no particulates are formed, and the vapor condenses on the gas passage surfaces. It addresses the need to cleanup an inert gas contaminated with cadmium which may escape from the electrochemical processing of Integral Fast Reactor (IFR) fuel in a hot cell. The IFR is a complete, self-contained, sodium-cooled, pool-type fast reactor fueled with a metallic alloy of uranium, plutonium and zirconium, and is equipped with a close-coupled fuel cycle. Tests with a model have shown that removal of cadmium from argon gas is in the order of 99.99%. The invention could also apply to the industrial cleanup of air or other gases contaminated with zinc, lead, or mercury. In addition, the invention has application in the cleanup of other gas systems contaminated with metal vapors which may be toxic or unhealthy.
Date: September 19, 1994
Creator: Ahluwalia, R.K. & Im, K.H.
Partner: UNT Libraries Government Documents Department

High energy bursts from a solid state laser operated in the heat capacity limited regime

Description: Solid state laser technology is a very well developed field and numerous embodiments and modes of operation have been demonstrated. A more recent development has been the pumping of a solid state laser active medium with an array of diode lasers (diode pumping, for short). These diode pump packages have previously been developed to pump solid state lasers with good efficiency, but low average power. This invention is a method and the resulting apparatus for operating a solid state laser in the heat capacity mode. Instead of cooling the laser, the active medium will heat up until it reaches some maximum acceptable temperature. The waste heat is stored in the active medium itself.
Date: December 31, 1994
Creator: Albrecht, G.; George, E.V. & Krupke, W.
Partner: UNT Libraries Government Documents Department

Micromachined silicon electrostatic chuck

Description: In the field of microelectronics, and in particular the fabrication of microelectronics during plasma etching processes, electrostatic chucks have been used to hold silicon wafers during the plasma etching process. Current electrostatic chucks that operate by the {open_quotes}Johnson-Rahbek Effect{close_quotes} consist of a metallic base plate that is typically coated with a thick layer of slightly conductive dielectric material. A silicon wafer of approximately the same size as the chuck is placed on top of the chuck and a potential difference of several hundred volts is applied between the silicon and the base plate of the electrostatic chuck. This causes an electrostatic attraction proportional to the square of the electric field in the gap between the silicon wafer and the chuck face. When the chuck is used in a plasma filled chamber the electric potential of the wafer tends to be fixed by the effective potential of the plasma. The purpose of the dielectric layer on the chuck is to prevent the silicon wafer from coming into direct electrical contact with the metallic part of the chuck and shorting out the potential difference. On the other hand, a small amount of conductivity appears to be desirable in the dielectric coating so that much of its free surface between points of contact with the silicon wafer is maintained near the potential of the metallic base plate; otherwise, a much larger potential difference would be needed to produce a sufficiently large electric field in the vacuum gap between the wafer and chuck. Typically, the face of the chuck has a pattern of grooves in which about 10 torr pressure of helium gas is maintained. This gas provides cooling (thermal contact) between the wafer and the chuck. A pressure of 10 torr is equivalent to about 0.2 psi.
Date: December 31, 1994
Creator: Anderson, R.A. & Seager, C.H.
Partner: UNT Libraries Government Documents Department

Portable gas chromatograph-mass spectrometer

Description: A gas chromatograph-mass spectrometer (GC-MS) for use as a field portable organic chemical analysis instrument. The GC-MS is designed to be contained in a standard size suitcase, weighs less than 70 pounds, and requires less than 600 watts of electrical power at peak power (all systems on). The GC-MS includes: a conduction heated, forced air cooled small bore capillary gas chromatograph, a small injector assembly, a self-contained ion/sorption pump vacuum system, a hydrogen supply, a dual computer system used to control the hardware and acquire spectrum data, and operational software used to control the pumping system and the gas chromatograph. This instrument incorporates a modified commercial quadrupole mass spectrometer to achieve the instrument sensitivity and mass resolution characteristic of laboratory bench top units.
Date: December 31, 1994
Creator: Andresen, B.D.; Eckels, J.D.; Kimmins, J.F. & Myers, D.W.
Partner: UNT Libraries Government Documents Department

Radar transponder apparatus and signal processing technique

Description: An active, phase-coded, time-grating transponder and a synthetic-aperture radar (SAR) and signal processor means, in combination, allow the recognition and location of the transponder (tag) in the SAR image and allow communication of information messages from the transponder to the SAR. The SAR is an illuminating radar having special processing modifications in an image-formation processor to receive an echo from a remote transponder, after the transponder receives and retransmits the SAR illuminations, and to enhance tile transponder`s echo relative to surrounding ground clutter by recognizing special transponder modulations from phase-shifted from the transponder retransmissions. The remote radio-frequency tag also transmits information to the SAR through a single antenna that also serves to receive the SAR illuminations. Unique tag-modulation and SAR signal processing techniques, in combination, allow the detection and precise geographical location of the tag, through the reduction of interfering signals from ground clutter, and allow communication of environmental and status information from said tag to be communicated to said SAR.
Date: December 31, 1994
Creator: Axline, R.M. Jr.; Sloan, G.R. & Spalding, R.E.
Partner: UNT Libraries Government Documents Department

Ceramic membranes for partial oxygenation of hydrocarbon fuels to high-value-added products

Description: This report describes the design of a membrane reactor for converting methane into value added products. The design includes an outer tube of perovskite which contacts air, an inner tube of zirconium oxide which contacts methane, and a bonding layer of a mixture of zirconium oxide and perovskite.
Date: December 31, 1994
Creator: Balachandran, U.; Dusek, J.T.; Kleefisch, M.S. & Kobylinski, T.P.
Partner: UNT Libraries Government Documents Department

Rapid formation of phase-clean 110 K (Bi-2223) powders derived via freeze-drying process

Description: This invention relates to an improved process of preparing Bi-Sr-Ca-Cu-O (BSCCO) powders, and more particularly, to a process for preparing BSCCO powders that utilize freeze-drying. The process generally includes splat freezing a nitrate solution of Bi, Pb, Sr, Ca, and Cu to form flakes of the solution; grinding the flakes to form a powder; freeze-drying the frozen powder; heating the powder to form dry green precursor powders; denitrating the powders; and heating the powders to form phase-clean Bi-2223 powders.
Date: December 31, 1994
Creator: Balachandran, U.; Krishnaraj, P.; Eror, N.G. & Lelovic, M.
Partner: UNT Libraries Government Documents Department

Optical apparatus and method for sensing uranyl

Description: An optical sensing device for uranyl and other substances, a method for making an optical sensing device and a method for chemically binding uranyl and other indicators to glass, quartz, cellulose and similar substrates. The indicator, such as arsenazo III, is immobilized on the substrate using a chemical binding process. The immobilized arsenazo III causes uranyl from a fluid sample to bind irreversibly to the substrate at its active sites, thus causing absorption of a portion of light transmitted through the substrate. Determination of the amount of light absorbed, using conventional means, yields the concentration of uranyl present in the sample fluid. The binding of uranyl on the substrate can be reversed by subsequent exposure of the substrate to a solution of 2,6-pyridinedicarboxylic acid. The chemical binding process is suitable for similarly binding other indicators, such as bromocresol green.
Date: January 1, 1994
Creator: Baylor, L.C. & Buchanan, B.R.
Partner: UNT Libraries Government Documents Department

Composition for detecting uranyl

Description: The present invention relates to an indicator composition for use in spectrophotometric detection of a substance in a solution, and a method for making the composition. Useful indicators are sensitive to the particular substance being measured, but are unaffected by the fluid and other chemical species that may be present in the fluid. Optical indicators are used to measure the uranium concentration of process solutions in facilities for extracting uranium from ores, production of nuclear fuels, and reprocessing of irradiated fuels. The composition comprises an organohalide covalently bonded to an indicator for the substance, in such a manner that the product is itself an indicator that provides increased spectral resolution for detecting the substance. The indicator is preferably arsenazo III and the organohalide is preferably cyanuric chloride. These form a composition that is ideally suited for detecting uranyl.
Date: January 1, 1994
Creator: Baylor, Lewis C. & Stephens, Susan M.
Partner: UNT Libraries Government Documents Department

Method for compression of data using single pass LZSS and run-length encoding

Description: A method used preferably with LZSS-based compression methods for compressing a stream of digital data. The method uses a run-length encoding scheme especially suited for data strings of identical data bytes having large run-lengths, such as data representing scanned images. The method reads an input data stream to determine the length of the data strings. Longer data strings are then encoded in one of two ways depending on the length of the string. For data strings having run-lengths less than 18 bytes, a cleared offset and the actual run-length are written to an output buffer and then a run byte is written to the output buffer. For data strings of 18 bytes or longer, a set offset and an encoded run-length are written to the output buffer and then a run byte is written to the output buffer. The encoded run-length is written in two parts obtained by dividing the run length by a factor of 255. The first of two parts of the encoded run-length is the quotient; the second part is the remainder. Data bytes that are not part of data strings of sufficient length are written directly to the output buffer.
Date: January 1, 1994
Creator: Berlin, Gary J.
Partner: UNT Libraries Government Documents Department

Cermet crucible for metallurgical processing

Description: A cermet crucible for metallurgically processing metals having high melting points comprising a body consisting essentially of a mixture of calcium oxide and erbium metal, the mixture comprising calcium oxide in a range between about 50 and 90% by weight and erbium metal in a range between about 10 and 50% by weight.
Date: December 31, 1994
Creator: Boring, C.P.
Partner: UNT Libraries Government Documents Department

Variable depth core sampler

Description: This invention relates to a sampling means, more particularly to a device to sample hard surfaces at varying depths. Often it is desirable to take samples of a hard surface wherein the samples are of the same diameter but of varying depths. Current practice requires that a full top-to-bottom sample of the material be taken, using a hole saw, and boring a hole from one end of the material to the other. The sample thus taken is removed from the hole saw and the middle of said sample is then subjected to further investigation. This paper describes a variable depth core sampler comprimising a circular hole saw member, having longitudinal sections that collapse to form a point and capture a sample, and a second saw member residing inside the first hole saw member to support the longitudinal sections of the first member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside the the first hole saw member.
Date: December 31, 1994
Creator: Bourgeois, P. M. & Reger, R. J.
Partner: UNT Libraries Government Documents Department

Pressurized security barrier and alarm system

Description: A security barrier for placement across a passageway is made up of interconnected pressurized tubing made up in a grid pattern with openings too small to allow passage. The tubing is connected to a pressure switch, located away from the barrier site, which activates an alarm upon occurrence of a pressure drop. A reinforcing bar is located inside and along the length of the tubing so as to cause the tubing to rupture and set off the alarm upon an intruder`s making an attempt to crimp and seal off a portion of the tubing by application of a hydraulic tool. Radial and rectangular grid patterns are disclosed.
Date: December 31, 1994
Creator: Carver, D.W.
Partner: UNT Libraries Government Documents Department

Wafer-scale charge isolation technique

Description: An apparatus and method are described which improve the performance of charge-coupled devices (CCD) in the presence of ionizing radiation. The invention is a wafer scale charge isolation technique which inhibits or reduces the flow of electrons created by the passage of ionizing radiation in the bulk regions of a silicon CCD. The technique has been tested in a device designed for operating in the infra-red wavelength band. The technique prevents charge from reaching the active charge collection volume of a pixel in a CCD.
Date: December 31, 1994
Creator: Colella, N.J. & Kimbrough, J.R.
Partner: UNT Libraries Government Documents Department

Fiber optic inclination detector system

Description: A fiber optic inclination detector system for determining the angular displacement of an object from a reference surface includes a simple mechanical transducer which requires a minimum number of parts and no electrical components. The system employs a single light beam which is split into two light beams and provided to the transducer. Each light beam is amplitude modulated upon reflecting off the transducer to detect inclination. The power values associated with each of the reflected light beams are converted by a pair of photodetectors into voltage signals, and a microprocessor manipulates the voltage signals to provide a measure of the angular displacement between the object and the reference surface.
Date: December 31, 1994
Creator: Cwalinski, J.P.
Partner: UNT Libraries Government Documents Department

Integral window hermetic fiber optic components

Description: In the fabrication of igniters, actuators, detonators, and other pyrotechnic devices to be activated by a laser beam, an integral optical glass window is formed by placing a preform in the structural member of the device and then melting the glass and sealing it in place by heating at a temperature between the ceramming temperature of the glass and the melting point of the metal, followed by rapid furnace cooling to avoid devitrification. No other sealing material is needed to achieve hermeticity. A preferred embodiment of this type of device is fabricated by allowing the molten glass to flow further and form a plano-convex lens integral with and at the bottom of the window. The lens functions to decrease the beam divergence caused by refraction of the laser light passing through the window when the device is fired by means of a laser beam.
Date: December 31, 1994
Creator: Dalton, Rick D.; Kramer, Daniel P.; Massey, Richard T. & Waker, Dalton A.
Partner: UNT Libraries Government Documents Department

Crimp sealing of tubes flush with or below a fixed surface

Description: An apparatus for crimp sealing and severing tubes flush or below a fixed surface. Tube crimping below a fixed surface requires an asymmetric die and anvil configuration. The anvil must be flat so that, after crimping, it may be removed without deforming the crimped tubes. This asymmetric die and anvil is used when a ductile metal tube and valve assembly are attached to a pressure vessel which has a fixed surface around the base of the tube at the pressure vessel. A flat anvil is placed against the tube. Die guides are placed against the tube on a side opposite the anvil. A pinch-off die is inserted into the die guides against the tube. Adequate clearance for inserting the die and anvil around the tube is needed below the fixed surface. The anvil must be flat so that, after crimping, it may be removed without deforming the crimped tubes.
Date: December 1994
Creator: Fischer, Jon E.; Walmsley, Don & Wapman, P. Derek
Partner: UNT Libraries Government Documents Department

Biocarrier Composition for and Method of Degrading Pollutants

Description: The present invention relates to biocarrier compositions that attract and bond pollutant-degrading antigens that will degrade the pollutants. Biocarriers are known generally as a variety of inert or semi-inert compounds or structures having the ability to sequester (attract), hold and biomagnify (enhance) specific microorganisms within their structure. Glass or polystyrene beads are the most well known biocarriers. The biocarrier, which is preferably in the form of glass microspheres, is coated with an antibody or group of antibodies that attract and react specifically with certain pollutant-degrading antigens. The antibody, once bonded to the biocarrier, is used by the composition to attract and bond those pollutant-degrading antigens. Each antibody is specific for an antigen that is specific for a given pollutant. The resulting composition is subsequently exposed to an environment contaminated with pollutants for degradation. In the preferred use, the degrading composition is formed and then injected directly into or near a plume or source of contamination.
Date: January 1, 1994
Creator: Fliermans, Carl B.
Partner: UNT Libraries Government Documents Department

Microfabricated microengine for use as a mechanical drive and power source in the microdomain and fabrication process

Description: A microengine uses two synchronized linear actuators as a power source and converts oscillatory motion from the actuators into rotational motion via direct linkage connection to an output gear or wheel. The microengine provides output in the form of a continuously rotating output gear that is capable of delivering drive torque to a micromechanism. The microengine can be operated at varying speeds and its motion can be reversed. Linear actuators are synchronized in order to provide linear oscillatory motion to the linkage means in the X and Y directions according to a desired position, rotational direction and speed of said mechanical output means. The output gear has gear teeth on its outer perimeter for directly contacting a micromechanism requiring mechanical power. The gear is retained by a retaining means which allows said gear to rotate freely. The microengine is microfabricated of polysilicon on one wafer using surface micromachining batch fabrication.
Date: December 31, 1994
Creator: Garcia, Ernest J. & Sniegowski, Jeffry J.
Partner: UNT Libraries Government Documents Department

Froth height level sensor

Description: A single sensor, comprised of a tube located near the foaming liquid, and another well away from the first, are used to determine the existence of foam in the vicinity of the probe. Two sensors a known distance apart can be used to locate the froth assuming a uniform froth density. The present invention utilizes the pressure differential existing between process chamber ambient pressure and the froth pressure to determine the existence of a froth and its location. Where froth density is not constant, multiple sensors at differing heights with respect to each other, or a single movable sensor, are used. Information derived using the multiple or movable sensor yields unambiguous froth density and height data.
Date: December 31, 1994
Creator: Glaser, J.W.; Holmes, L.; Upadhye, R.S. & Wilder, J.G.
Partner: UNT Libraries Government Documents Department

Free form hemispherical shaped charge

Description: A hemispherical shaped charge has been modified such that one side of the hemisphere is spherical and the other is a spherical allowing a wall thickness variation in the liner. A further modification is to use an elongated hemispherical shape. The liner has a thick wall at its pole and a thin wall at the equator with a continually decreasing wall thickness from the pole to the equator. The ratio of the wall thickness from the pole to the equator varies depending on liner material and HE shape. Hemispherical shaped charges have previously been limited to spherical shapes with no variations in wall thicknesses. By redesign of the basic liner thicknesses, the jet properties of coherence, stability, and mass distribution have been significantly improved. It is an object of this invention to provide an improved shape charge for oil well perforation.
Date: December 31, 1994
Creator: Haselman, Leonard C., Jr.
Partner: UNT Libraries Government Documents Department

Immersible solar heater for fluids

Description: An immersible solar heater is described comprising a light-absorbing panel attached to a frame for absorbing heat energy from the light and transferring the absorbed heat energy directly to the fluid in which the heater is immersed. The heater can be used to heat a swimming pool, for example, and is held in position and at a preselected angle by a system of floats, weights and tethers so that the panel can operate efficiently. A skid can be used in one embodiment to prevent lateral movement of the heater along the bottom of the pool. Alternative embodiments include different arrangements of the weights, floats and tethers and methods for making the heater.
Date: January 1, 1994
Creator: Hazen, T. C. & Fliermans, C. B.
Partner: UNT Libraries Government Documents Department

Double row loop-coil configuration for high-speed electrodynamic maglev suspension, guidance, propulsion and guideway directional switching

Description: A stabilization and propulsion system comprising a series of loop-coils arranged in parallel rows wherein two rows form a magnetic rail. Levitation and lateral stability is provided when the induced field in the magnetic rails interacts with the superconducting magnets (SCM) mounted on the magnetic levitation vehicle. A multiphase propulsion system interconnects specific coils in a given magnetic rail and interacts with the SCM to produce a propulsion force to the vehicle.
Date: December 31, 1994
Creator: He, J. & Rote, D.M.
Partner: UNT Libraries Government Documents Department

No moving parts safe and arm apparatus and method with monitoring and built-in-test for optical firing of explosive systems

Description: A laser initiated ordnance controller apparatus which provides a safe and arm scheme with no moving parts. The safe and arm apparatus provides isolation of firing energy to explosive devices using a combination of polarization isolation and control through acousto-optical deviation of laser energy pulses. The apparatus provides constant monitoring of the systems status and performs 100% built-in-test at any time prior to ordnance ignition without the risk of premature ignition or detonation. The apparatus has a computer controller, a solid state laser, an acousto-optic deflector and RF drive circuitry, built-in-test optics and electronics, and system monitoring capabilities. The optical system is completed from the laser beam power source to the pyrotechnic ordnance through fiber optic cabling, optical splitters and optical connectors. During operation of the apparatus, a command is provided by the computer controller and, simultaneous with laser flashlamp fire, the safe and arm device is opened for approximately 200 microseconds which allows the laser pulse to transmit through the device. The arm signal also energizes the laser power supply and activated the acousto-optical deflector. When the correct fire format command is received, the acousto-optic deflector moves to the selected event channel and the channel is verified to ensure the system is pointing to the correct position. Laser energy is transmitted through the fiber where an ignitor or detonator designed to be sensitive to optical pulses is fired at the end of the fiber channel.
Date: December 31, 1994
Creator: Hendrix, James L.
Partner: UNT Libraries Government Documents Department