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High current pulse transmission cable (open access)

High current pulse transmission cable

This invention is comprised of a transmission cable for carrying high current pulses in which an even numbered plurality of electrical conductors surrounds a central ground conductor. Each electrical conductor is connected so that it at any instant in time it will carry current of opposite polarity to the polarity carried by adjacent conductors. This arrangement cancels practically all of the external fields generated by current in the conductors.
Date: September 28, 1990
Creator: Parsons, W. M.
System: The UNT Digital Library
Clay enhancement of methane, low molecular weight hydrocarbon and halocarbon conversion by methanotrophic bacteria (open access)

Clay enhancement of methane, low molecular weight hydrocarbon and halocarbon conversion by methanotrophic bacteria

The invention described in this report relates to a combined system of an apparatus and a method of increasing the rates of oxidation of gases and hazardous vapors by methanotrophic and other bacteria. The gases of interest are methane and trichlorethylene and other hazardous vapors. In a preferred embodiment, the oxidation rate of methane is improved by the addition of clays, e.g., kaolin, sometimes called ``China clay.``
Date: December 31, 1991
Creator: Apel, W. A. & Dugan, P. R.
System: The UNT Digital Library
Method for distinguishing normal and transformed cells using G1 kinase inhibitors (open access)

Method for distinguishing normal and transformed cells using G1 kinase inhibitors

A G{sub 1} phase kinase inhibitor is applied in a low concentration to a population of normal and transformed mammalian cells. The concentration of G{sub 1} phase kinase inhibitor is selected to reversibly arrest normal mammalian cells in the G{sub 1} cell cycle without arresting growth of transformed cells. The transformed cells may then be selectively identified and/or cloned for research or diagnostic purposes. The transformed cells may also be selectively killed by therapeutic agents that do not affect normal cells in the G{sub 1} phase, suggesting that such G{sub 1} phase kinase inhibitors may form an effective adjuvant for use with chemotherapeutic agents in cancer therapy for optimizing the killing dose of chemotherapeutic agents while minimizing undesirable side effects on normal cells.
Date: December 31, 1991
Creator: Crissman, H. A.; Gadbois, D. M.; Tobey, R. A. & Bradbury, E. M.
System: The UNT Digital Library
Molybdenum disilicide composites reinforced with zirconia and silicon carbide (open access)

Molybdenum disilicide composites reinforced with zirconia and silicon carbide

This patent pertains to compositions consisting essentially of molybdenum disilicide, silicon carbide, and a zirconium oxide component. The silicon carbide used in the compositions is in whisker or powder form. The zirconium oxide component is pure zirconia or partially stabilized zirconia or fully stabilized zirconia. Fabrication, fracture toughness, and bend strength are covered.
Date: December 31, 1992
Creator: Petrovic, J. J.
System: The UNT Digital Library
Reflective Optical Imaging System for Extreme Ultraviolet Wavelengths (open access)

Reflective Optical Imaging System for Extreme Ultraviolet Wavelengths

This invention is comprised of a projection reflection optical system having two mirrors in a coaxial, four reflection configuration to reproduce the image of an object. The mirrors have aspherical reflection surfaces to provide a very high resolution of object feature wavelengths less than 200 {mu}m, and preferably less than 100 {mu}m. An image resolution of features less than 0.05--0.1 {mu}m, is obtained over a large area field; i.e., 25.4 mm {times} 25.4 mm, with a distortion less than 0.1 of the resolution over the image field.
Date: December 31, 1991
Creator: Viswanathan, V. K. & Newnam, B. E.
System: The UNT Digital Library
No-carrier-added (NCA) aryl [{sup 18}F]fluorides via the nucleophilic aromatic substitution of electron rich aromatic rings (open access)

No-carrier-added (NCA) aryl [{sup 18}F]fluorides via the nucleophilic aromatic substitution of electron rich aromatic rings

A method for synthesizing no-carrier-added (NCA) aryl [{sup 18}F] fluoride substituted aromatic aldehyde compositions bearing an electron donating group is described. The method includes the step of reacting aromatic nitro aldehydes having a suitably protected hydroxyl substituent on an electron rich ring. The reaction is carried out by nucleophilic aromatic substitution with a no-carrier-added (NCA) [{sup 18}F]fluoride ion. The method can be used to synthesize various no-carrier-added aryl [{sup 18}F]fluoride compositions, including 6-[{sup 18}F]fluoro-L-DOPA, 2-[{sup 18}F]fluorotyrosine, 6-[{sup 18}F]fluoronorepinephrine, and 6-[{sup 18}F]fluorodopamine. In those instances when a racemic mixture of enantiomers is produced by the present invention, such as in the synthesis of 6-[{sup 18}F]fluoronorepinephrine, a preferred method also includes resolution of the racemic mixture on a chiral HPLC column. This procedure results in a high yield of enantiomerically pure [{sup 18}F] labeled isomers, for example [-]-6-[{sup 18}F]fluoronorepinephrine and [+]-6-[{sup 18}F]fluoronorepinephrine.
Date: December 31, 1991
Creator: Ding, Yu-Shin; Fowler, J. S. & Wolf, A. P.
System: The UNT Digital Library
Process for alloying uranium and niobium (open access)

Process for alloying uranium and niobium

Alloys such as U-6Nb are prepared by forming a stacked sandwich array of uranium sheets and niobium powder disposed in layers between the sheets, heating the array in a vacuum induction melting furnace to a temperature such as to melt the uranium, holding the resulting mixture at a temperature above the melting point of uranium until the niobium dissolves in the uranium, and casting the uranium-niobium solution. Compositional uniformity in the alloy product is enabled by use of the sandwich structure of uranium sheets and niobium powder.
Date: December 31, 1990
Creator: Holcombe, Cressie E.; Northcutt, Walter G.; Masters, David R. & Chapman, Lloyd R.
System: The UNT Digital Library
Simplified flangeless unisex waveguide coupler assembly (open access)

Simplified flangeless unisex waveguide coupler assembly

A unisex coupler assembly is disclosed capable of providing a leak tight coupling for waveguides with axial alignment of the waveguides and rotational capability. The sealing means of the coupler assembly are not exposed to RF energy, and the coupler assembly does not require the provision of external flanges on the waveguides. In a preferred embodiment, O ring seals are not used and the coupler assembly is, therefore, bakeable at a temperature up to about 150{degrees}C. The coupler assembly comprises a split collar which clamps around the waveguides and a second collar which fastens to the split collar. The split collar contains an inner annular groove. Each of the waveguides is provided with an external annular groove which receives a retaining ring. The split collar is clamped around one of the waveguides with the inner annular groove of the split collar engaging the retaining ring carried in the external annular groove in the waveguide. The second collar is then slipped over the second waveguide behind the annular groove and retaining ring therein and the second collar is coaxially secured by fastening means to the split collar to draw the respective waveguides together by coaxial force exerted by the second collar …
Date: December 31, 1992
Creator: DiMartino, M. & Moeller, C. P.
System: The UNT Digital Library
Jet plume injection and combustion system for internal combustion engines (open access)

Jet plume injection and combustion system for internal combustion engines

This invention is comprised of an improved combustion system for an internal combustion engine is disclosed wherein a rich air/fuel mixture is furnished at high pressure to one or more jet plume generator cavities adjacent to a cylinder and then injected through one or more orifices from the cavities into the head space of the cylinder to form one or more turbulent jet plumes in the head space of the cylinder prior to ignition of the rich air/fuel mixture in the cavity of the jet plume generator. The portion of the rich air/fuel mixture remaining in the cavity of the generator is then ignited to provide a secondary jet, comprising incomplete combustion products which are injected into the cylinder to initiate combustion in the already formed turbulent jet plume. Formation of the turbulent jet plume in the head space of the cylinder prior to ignition has been found to yield a higher maximum combustion pressure in the cylinder, as well as shortening the time period to attain such a maximum pressure.
Date: December 31, 1992
Creator: Oppenheim, A. K.; Maxson, J. A. & Hensinger, D. M.
System: The UNT Digital Library
Solid state laser media driven by remote nuclear powered fluorescence (open access)

Solid state laser media driven by remote nuclear powered fluorescence

An apparatus is provided for driving a solid state laser by a nuclear powered fluorescence source which is located remote from the fluorescence source. A nuclear reaction produced in a reaction chamber generates fluorescence or photons. The photons are collected from the chamber into a waveguide, such as a fiber optic waveguide. The waveguide transports the photons to the remote laser for exciting the laser.
Date: January 16, 1991
Creator: Prelas, M. A.
System: The UNT Digital Library
HEPA filter dissolution process (open access)

HEPA filter dissolution process

This invention is comprised of a process for dissolution of spent high efficiency particulate air (HEPA) filters and then combining the complexed filter solution with other radioactive wastes prior to calcining the mixed and blended waste feed. The process is an alternate to a prior method of acid leaching the spent filters which is an inefficient method of treating spent HEPA filters for disposal.
Date: December 31, 1992
Creator: Brewer, K. N. & Murphy, J. A.
System: The UNT Digital Library
Electrical safety device (open access)

Electrical safety device

This invention consists of an electrical safety device for use in power tools that is designed to automatically discontinue operation of the power tool upon physical contact of the tool with a concealed conductive material. A step down transformer is used to supply the operating power for a disconnect relay and reset delay. When physical contact is made between the power tool and the conductive material, an electrical circuit through the disconnect relay is completed and the operation of the power tool is automatically interrupted. Once the contact between the tool and conductive material is broken, the power tool can be quickly and easily reactivated by a reset push button activating the reset relay. A remote reset is provided for convenience and efficiency of operation.
Date: September 6, 1990
Creator: White, D. B.
System: The UNT Digital Library
Propulsion and stabilization system for magnetically levitated vehicles (open access)

Propulsion and stabilization system for magnetically levitated vehicles

A propulsion and stabilization system for an inductive repulsion type magnetically levitated vehicle which is propelled and stabilized by a system which includes propulsion windings mounted above and parallel to vehicle-borne suspension magnets. A linear synchronous motor is part of the vehicle guideway and is mounted above and parallel to superconducting magnets attached to the magnetically levitated vehicle.
Date: December 31, 1992
Creator: Coffey, H. T.
System: The UNT Digital Library
Calcination and solid state reaction of ceramic-forming components to provide single-phase ceramic product having fine particle size (open access)

Calcination and solid state reaction of ceramic-forming components to provide single-phase ceramic product having fine particle size

The invention consists of an improved method for the preparation of single phase, fine grained ceramic materials from precursor powder mixtures where at least one of the components of the mixture is an alkali earth carbonate. The process consists of heating the precursor powders in a partial vacuum under flowing oxygen and under conditions where the partial pressure of CO{sub 2} evolved during the calcination is kept to a very low level relative to the oxygen. The process has been found particularly suitable for the preparation of high temperature copper oxide superconducting materials such as YBa{sub 2}Cu{sub 3}O{sub x} ``123`` and YBa{sub 2}Cu{sub 4}O{sub 8} ``124``.
Date: September 28, 1990
Creator: Balachandran, U.; Poeppel, R. B.; Emerson, J. E. & Johnson, S. A.
System: The UNT Digital Library
In-situ remediation system for groundwater and soils (open access)

In-situ remediation system for groundwater and soils

The present invention relates to a system for in-situ remediation of contaminated groundwater and soil. In particular the present invention relates to stabilizing toxic metals in groundwater and soil. The United States Government has rights in this invention pursuant to Contract No. DE-AC09-89SR18035 between the US Department of Energy and Westinghouse Savannah River Company.
Date: January 1, 1991
Creator: Corey, J. C.; Kaback, D. S. & Looney, B. B.
System: The UNT Digital Library
Silicon nitride reinforced with molybdenum disilicide (open access)

Silicon nitride reinforced with molybdenum disilicide

Compositions of matter comprised of silicon nitride and molybdenum disilicide and methods of making the compositions, where the molybdenum disilicide is present in amounts ranging from about 5 to about 50 vol%.
Date: December 31, 1990
Creator: Petrovic, John J. & Honnell, Richard E.
System: The UNT Digital Library
Production of hollow aerogel microspheres (open access)

Production of hollow aerogel microspheres

A method is described for making hollow aerogel microspheres of 800--1200{mu} diameter and 100--300{mu} wall thickness by forming hollow alcogel microspheres during the sol/gel process in a catalytic atmosphere and capturing them on a foam surface containing catalyst. Supercritical drying of the formed hollow alcogel microspheres yields hollow aerogel microspheres which are suitable for ICF targets.
Date: December 31, 1990
Creator: Upadhye, Ravindra S. & Henning, Sten A.
System: The UNT Digital Library
Cesium iodide alloys (open access)

Cesium iodide alloys

This invention relates to a CsI composition with improved mechanical strength and outstanding multispectral infrared transmittance, for window use. The additive is a monovalent iodide, other than CsI, added in amounts sufficient to maximize fracture strength from 16 to 40 MPa, while maintaining at least 10% transparency in the 4 to 50 micrometer wavelength range. The preferred additive is AgI, although RbI or CuI can be used. 6 figs. (DLC)
Date: January 1, 1991
Creator: Kim, Hyoun-Ee & Moorhead, A. J.
System: The UNT Digital Library
Method of solubilizing phthalocyanines and metallophthalocyanines (open access)

Method of solubilizing phthalocyanines and metallophthalocyanines

A one-step method of manufacturing soluble phthalocyanines and metallophthalocyanines, like zinc phthalocyanine, by converting a phthalocyanine or a metallophthalocyanine to a trialkylsilyl-substituted derivative is disclosed. The phthalocyanine or metallophthalocyanine is converted to a soluble trialkylsilyl-substituted derivative by interacting the phthalocyanine or metallophthalocyanine with an active metal amide, like lithium 2,2,6, 6-tetra-methylpiperidide, and a halotrialkylsilane, like chlorotrimethylsilane, to provide a phthalocyanine compound, like phthalocyanine monomers, dimers or polymers, metalated or unmetalated, that are soluble in organic media.
Date: June 1, 1990
Creator: Rathke, Jerome W.; Chen, Michael J. & Fendrick, Carol M.
System: The UNT Digital Library
Method and apparatus for transporting liquid slurries (open access)

Method and apparatus for transporting liquid slurries

An improved method and device to prevent erosion of slurry transport devices is disclosed which uses liquid injection to prevent contact by the slurry composition with the inner surface of the walls of the transport system. A non-abrasive liquid is injected into the slurry transport system and maintains intimate contact with the entire inner surface of the transport system, thereby creating a fluid barrier between the nonabrasive liquid and the inner surface of the transport system which thereby prevents erosion.
Date: January 1, 1991
Creator: Berry, Gregory F.; Lyczkowski, Robert W. & Wang, Chi-Sheng
System: The UNT Digital Library
Process of making cryogenically cooled high thermal performance crystal optics (open access)

Process of making cryogenically cooled high thermal performance crystal optics

A method for constructing a cooled optic wherein one or more cavities are milled, drilled or formed using casting or ultrasound laser machining techniques in a single crystal base and filled with porous material having high thermal conductivity at cryogenic temperatures. A non-machined strain-free single crystal can be bonded to the base to produce superior optics. During operation of the cooled optic, N{sub 2} is pumped through the porous material at a sub-cooled cryogenic inlet temperature and with sufficient system pressure to prevent the fluid bulk temperature from reaching saturation.
Date: June 29, 1990
Creator: Kuzay, Tuncer M.
System: The UNT Digital Library
Cooler and particulate separator for an off-gas stack (open access)

Cooler and particulate separator for an off-gas stack

This report describes an off-gas stack for a melter, furnace or reaction vessel comprising an air conduit leading to two sets of holes, one set injecting air into the off-gas stack near the melter plenum and the second set injecting air downstream of the first set. The first set injects air at a compound angle, having both downward and tangential components, to create a reverse vortex flow, counter to the direction of flow of gas through the stack and also along the periphery of the stack interior surface. Air from the first set of holes prevents recirculation zones from forming and the attendant accumulation of particulate deposits on the wall of the stack and will also return to the plenum any particulate swept up in the gas entering the stack. The second set of holes injects air in the same direction as the gas in the stack to compensate for the pressure drop and to prevent the concentration of condensate in the stack. A set of sprayers, receiving water from a second conduit, is located downstream of the second set of holes and sprays water into the gas to further cool it.
Date: April 8, 1991
Creator: Wright, G. T.
System: The UNT Digital Library
Three-Axis Particle Impact Probe (open access)

Three-Axis Particle Impact Probe

Three-axis particle impact probes detect particle impact vectors along x-, y-, and z-axes by means of a head mounted on the outer end of a shaft that is flexibly mounted in silicone rubber at the top of a housing so as to enable motion imparted to the head upon impact to be transmitted to a grounded electrode secured to the shaft within the housing. Excitable electrodes are mounted in the housing in a fixed position, spaced apart from the ground electrode and forming, with the ground electrode, capacitor pairs. Movement of the ground electrode results in changes in capacitance, and these differences in capacitance are used for measurement or derivation of momentum vectors along each of the three axes. In one embodiment, the ground electrode is mounted at the base of the shaft and is secured to a silicone rubber layer at the top of the housing, providing for cantilevered movement. In another embodiment, the shaft is mounted at its mid point in a flexible bushing so that it undergoes pivotal movement around that point.
Date: April 2, 1991
Creator: Fasching, G. E.; Smith, Nelson S., Jr. & Utt, C. E.
System: The UNT Digital Library
Linear electric field mass spectrometry (open access)

Linear electric field mass spectrometry

A mass spectrometer is described having a low weight and low power requirement, for use in space. It can be used to analyze the ionized particles in the region of the spacecraft on which it is mounted. High mass resolution measurements are made by timing ions moving through a gridless cylindrically sysmetric linear electric field.
Date: March 29, 1991
Creator: McComas, D. J. & Nordholt, J. E.
System: The UNT Digital Library