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Ammonia-treated phosphate glasses useful for sealing to metals

Description: A method of improving surface-dependent properties of phosphate glass such as durability and wear resistance without significantly affecting its thermal expansion coefficient is provided which comprises annealing the glass in a dry ammonia atmosphere at temperatures approximating the transition temperature of the glass. The ammonia annealing treatment of the present invention is carried out for a time sufficient to allow incorporation of a thin layer of nitrogen into the surface of the phosphate glass, and the treatment improves the durability of the glass without the reduction in the thermal expansion coefficient that has restricted the effectiveness of prior ammonia treatments. The improved phosphate glass resulting from this method is superior in wear resistance, yet maintains suitable thermal expansion properties so that it may be used effectively in a variety of applications requiring hermetic glass-metal seals.
Date: December 31, 1990
Creator: Brow, R. K. & Day, D. E.
Partner: UNT Libraries Government Documents Department

Apparatus and method for separating constituents

Description: A centrifugal separator apparatus and method for improving the efficiency of the separation of constituents in a fluid stream. A cyclone separator includes an assembly for separately discharging both constituents through the same end of the separator housing. A rotary separator includes a rotary housing having a baffle disposed therein for minimizing the differential rotational velocities of the constituents in the housing, thereby decreasing turbulence, and increasing efficiency. The intensity of the centrifugal force and the time which the constituents reside within the housing can be independently controlled to improve efficiency of separation. 4 figs.
Date: December 31, 1990
Creator: Maronde, C. P. & Killmeyer, R. P., Jr.
Partner: UNT Libraries Government Documents Department

Background-reducing x-ray multilayer mirror

Description: This invention is comprised of a background-reducing x-ray multilayer mirror. A multiple-layer ``wavetrap`` deposited over the surface of a layered synthetic microstructure soft x-ray mirror optimized for reflectivity at chosen wavelengths is disclosed for reducing the reflectivity of undesired, longer wavelength incident radiation incident thereon. In three separate mirror designs employing an alternating molybdenum and silicon layered mirrored structure overlaid by two layers of a molybdenum/silicon pair anti-reflection coating, reflectivities of near normal incidence 133, 171, and 186 {Angstrom} wavelengths have been optimized, while that at 304 {Angstrom} has been minimized. The optimization process involves the choice of materials, the composition of the layer/pairs as well as the number thereof, and the distance therebetween for the mirror, and the simultaneous choice of materials, the composition of the layer/pairs, their number and distance for the ``wavetrap.``
Date: August 3, 1990
Creator: Bloch, J. J.; Roussel-Dupre, D. & Smith, B. W.
Partner: UNT Libraries Government Documents Department

A backscattering spectrometry device for identifying unknown elements present in a workpiece

Description: This invention is comprised of a backscattering spectrometry method and device for identifying and quantifying impurities in a workpiece during processing and manufacturing of that workpiece. While the workpiece is implanted with an ion beam, that same ion beam backscatters resulting from collisions with known atoms and with impurities within the workpiece. Those ions backscatter along a predetermined scattering angle and are filtered using a self-supporting filter to stop the ions with a lower energy because they collided with the known atoms of the workpiece of a smaller mass. Those ions which pass through the filter have a greater energy resulting from impact with impurities having a greater mass than the known atoms of the workpiece. A detector counts the number and measures the energy of the ions which pass through the filter. From the energy determination and knowledge of the scattering angle, a mass calculation determines the identity, and from the number and solid angle of the scattering angle, a relative concentration of the impurity is obtained.
Date: December 31, 1990
Creator: Doyle, Barney L. & Knapp, James A.
Partner: UNT Libraries Government Documents Department

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

Description: 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.
Partner: UNT Libraries Government Documents Department

Counterrotating brushless dc permanent magnet motor

Description: An brushless DC permanent magnet motor is provided for driving an autonomous underwater vehicle. In one embodiment, the motor comprises four substantially flat stators disposed in stacked relationship, with pairs of the stators being axially spaced and each of the stators comprising a tape-wound stator coil; and a first and second substantially flat rotors disposed between the spaced pairs of stators. Each of the rotors includes an annular array of permanent magnets embedded therein. A first shaft is connected to the first rotor and a second, concentric shaft is connected to the second rotor, and drive unit causes rotation of the two shafts in opposite directions. The second shaft comprises a hollow tube having a central bore therein in which the first shaft is disposed. Two different sets of bearings support the first and second shAfts. In another embodiment, the motor comprises two ironless stators and pairs and rotors mounted no opposite sides of the stators and driven by counterrotating shafts.
Date: December 31, 1990
Creator: Hawsey, R. A. & Bailey, J. M.
Partner: UNT Libraries Government Documents Department

Counterrotating brushless dc permanent magnet motor

Description: An brushless DC permanent magnet motor is provided for driving an autonomous underwater vehicle. In one embodiment, the motor comprises four substantially flat stators disposed in stacked relationship, with pairs of the stators being axially spaced and each of the stators comprising a tape-wound stator coil; and a first and second substantially flat rotors disposed between the spaced pairs of stators. Each of the rotors includes an annular array of permanent magnets embedded therein. A first shaft is connected to the first rotor and a second, concentric shaft is connected to the second rotor, and drive unit causes rotation of the two shafts in opposite directions. The second shaft comprises a hollow tube having a central bore therein in which the first shaft is disposed. Two different sets of bearings support the first and second shAfts. In another embodiment, the motor comprises two ironless stators and pairs and rotors mounted no opposite sides of the stators and driven by counterrotating shafts.
Date: January 1, 1990
Creator: Hawsey, R. A. & Bailey, J. M.
Partner: UNT Libraries Government Documents Department

Destruction of acid gas emissions

Description: A method of destroying NO{sub x} and SO{sub x} in a combustion gas is disclosed. The method includes generating active species by treating stable molecules in a high temperature plasma. Ammonia, methane, steam, hydrogen, nitrogen or a combustion of these gases can be selected as the stable molecules. The gases are subjected to plasma conditions sufficient to create free radicals, ions or excited atoms such as N, NH, NH{sub 2}, OH, CH and/or CH{sub 2}. These active species are injected into a combustion gas at a location of sufficiently high temperature to maintain the species in active state and permit them to react with NO{sub x} and SO{sub x}. Typically the injection is made into the immediate post-combustion gases at temperatures of 475--950{degrees}C. 1 fig.
Date: December 31, 1990
Creator: Mathur, M. P.; Fu, Yuan C.; Ekmann, J. M. & Boyle, J. M.
Partner: UNT Libraries Government Documents Department

Detection device for hazardous material

Description: This invention is comprised of a detection device that is activated by the interaction of a hazardous chemical with a coating interactive with said chemical on an optical fiber thereby reducing the amount of light passing through the fiber to a light detector. A combination of optical filters separates the light into a signal beam and a reference beam which after detection, appropriate amplification, and comparison with preset internal signals, activates an alarm means if a predetermined level of contaminant is observed.
Date: December 31, 1990
Creator: Partin, J. K. & Grey, A. E.
Partner: UNT Libraries Government Documents Department

Dual output acoustic wave sensor for molecular identification

Description: The invention comprises a method for the identification and quantification of sorbed chemical species onto a coating of a device capable of generating and receiving an acoustic wave, by measuring the changes in the velocity of the acoustic wave resulting from the sorption of the chemical species into the coating as the wave travels through the coating and by measuring the changes in the attenuation of an acoustic wave resulting from the sorption of the chemical species into the coating as the wave travels through the coating. The inventive method further correlates the magnitudes of the changes of velocity with respect to changes of the attenuation of the acoustic wave to identify the sorbed chemical species. The absolute magnitudes of the velocity changes or the absolute magnitude of the attenuation changes are used to determine the concentration of the identified chemical species.
Date: October 3, 1990
Creator: Frye, G. C. & Martin, S. J.
Partner: UNT Libraries Government Documents Department

Ductile nickel-silicon alloy

Description: An improvement over prior compositions wherein the ductility of Ni-Si alloys are improved with minor alloying additions of hafnium or zirconium.
Date: August 6, 1990
Creator: Oliver, W. C.
Partner: UNT Libraries Government Documents Department

Ductile nickel-silicon alloy

Description: An improvement over prior compositions wherein the ductility of Ni-Si alloys are improved with minor alloying additions of hafnium or zirconium.
Date: August 6, 1990
Creator: Oliver, W.C.
Partner: UNT Libraries Government Documents Department

Electrical safety device

Description: 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.
Partner: UNT Libraries Government Documents Department

Extrusion of metal oxide superconducting wire, tube or ribbon

Description: A process and apparatus for extruding a superconducting metal oxide composition YBa{sub 2}Cu{sub 3}O{sub 7-x} provides a wire (tube or ribbon) having a cohesive mass and a degree of flexibility together with enhanced electrical properties. Wire diameters in the range of 6--85 mils have been produced with smaller wires on the order of 10 mils in diameter exhibiting enhanced flexibility for forming braided, or multistrand, configurations for greater current carrying capacity. The composition for extrusion contains a polymeric binder to provide a cohesive mass to bind the particles together during the extrusion process with the binder subsequently removed at lower temperatures during sintering. The composition for extrusion further includes a deflocculent, an organic plasticizer and a solvent which also are subsequently removed during sintering. Electrically conductive tubing with an inner diameter of 52 mil and an outer diameter of 87--335 mil has also been produced. Flat ribbons have been produced in the range of 10--125 mil thick by 100--500 mil wide. The superconducting wire, tube or ribbon may include an outer ceramic insulating sheath co-extruded with the wire, tubing or ribbon.
Date: December 31, 1990
Creator: Dusek, Joseph T.
Partner: UNT Libraries Government Documents Department

Extrusion of metal oxide superconducting wire, tube or ribbon

Description: A process and apparatus for extruding a superconducting metal oxide composition YBa{sub 2}Cu{sub 3}O{sub 7-x} provides a wire (tube or ribbon) having a cohesive mass and a degree of flexibility together with enhanced electrical properties. Wire diameters in the range of 6--85 mils have been produced with smaller wires on the order of 10 mils in diameter exhibiting enhanced flexibility for forming braided, or multistrand, configurations for greater current carrying capacity. The composition for extrusion contains a polymeric binder to provide a cohesive mass to bind the particles together during the extrusion process with the binder subsequently removed at lower temperatures during sintering. The composition for extrusion further includes a deflocculent, an organic plasticizer and a solvent which also are subsequently removed during sintering. Electrically conductive tubing with an inner diameter of 52 mil and an outer diameter of 87--335 mil has also been produced. Flat ribbons have been produced in the range of 10--125 mil thick by 100--500 mil wide. The superconducting wire, tube or ribbon may include an outer ceramic insulating sheath co-extruded with the wire, tubing or ribbon.
Date: January 1, 1990
Creator: Dusek, J.T.
Partner: UNT Libraries Government Documents Department

Fiber optic detector

Description: This invention is comprised of a portable fiber optic detector that senses the presence of specific target chemicals by exchanging the target chemical for a fluorescently-tagged antigen that is bound to an antibody which is in turn attached to an optical fiber. Replacing the fluorescently-tagged antigen reduces the fluorescence so that a photon sensing detector records the reduced light level and activates an appropriate alarm or indicator.
Date: December 31, 1990
Creator: Partin, J. K.; Ward, T. E. & Grey, A. E.
Partner: UNT Libraries Government Documents Department

Flame quality monitor system for fixed firing rate oil burners

Description: A method and apparatus for determining and indicating the flame quality, or efficiency of the air-fuel ratio, in a fixed firing rate heating unit, such as an oil burning furnace, is provided. When the flame brightness falls outside a preset range, the flame quality, or excess air, has changed to the point that the unit should be serviced. The flame quality indicator output is in the form of lights mounted on the front of the unit. A green light indicates that the flame is about in the same condition as when the burner was last serviced. A red light indicates a flame which is either too rich or too lean, and that servicing of the burner is required. At the end of each firing cycle, the flame quality indicator goes into a hold mode which is in effect during the period that the burner remains off. A yellow or amber light indicates that the burner is in the hold mode. In this mode, the flame quality lights indicate the flame condition immediately before the burner turned off. Thus the unit can be viewed when it is off, and the flame condition at the end of the previous firing cycle can be observed.
Date: October 23, 1990
Creator: Butcher, T. A. & Cerniglia, P.
Partner: UNT Libraries Government Documents Department

Halogenated high {Tc} superconductors and method of preparation

Description: Disclosed is a method for producing a superconductor of the R-Ba-Cu-O system which comprises of selecting an insulating material of the formula RBa{sub x}Cu{sub y}O{sub z} where R is selected from the group consisting of Y, La, Pr, Nd, Sm, Eu, Gd, Ho, Er, Tm, and Lu, and where x ranges from about 1.7 to about 2.3, y ranges from about 2.7 to about 3.3 and z ranges from about 5.0 to about 6.99, and halogenating said material with a halogen selected from the group consisting of chlorine, bromine, iodine, and mixtures thereof, while maintaining said material at a temperature ranging from about 160 to about 440{degrees}C, for a period of time sufficient to cause incorporation of said halogen into said material. Also, disclosed are the materials produced by the method and articles of manufacture incorporating said materials as electronic circuitry components.
Date: November 14, 1990
Creator: Radousky, H. B.; Glass, R. S. & Fluss, M. J.
Partner: UNT Libraries Government Documents Department

High current pulse transmission cable

Description: 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.
Partner: UNT Libraries Government Documents Department

High density hexagonal boron nitride prepared by hot isostatic pressing in refractory metal containers

Description: Boron nitride powder with less than or equal to the oxygen content of starting powder (down to 0.5% or less) is hot isostatically pressed in a refractory metal container to produce hexagonal boron nitride with a bulk density greater than 2.0 g/cc. The refractory metal container is formed of tantalum, niobium, tungsten, molybdenum or alloys thereof in the form of a cansister or alternatively plasma sprayed or chemical vapor deposited onto a powder compact. Hot isostatic pressing at 1800{degrees}C and 30 KSI (206.8 MPa) argon pressure for four hours produces a bulk density of 2.21 g/cc. Complex shapes can be made.
Date: December 31, 1990
Creator: Hoenig, C. L.
Partner: UNT Libraries Government Documents Department

Highly conductive electrolyte composites and method of fabrication thereof

Description: An electrolyte composite is manufactured by pressurizing a mixture of ionically conductive glass and an ionically conductive compound at between 12,000 and 24,000 pounds per square inch to produce a pellet. The resulting pellet is then sintered at relatively lower temperatures (800{degrees}C--1200{degrees}C), for example 1000{degrees}C, than are typically required (1400{degrees}C) when fabricating single constituent ceramic electrolytes. The resultant composite is 100 percent conductive at 250{degrees}C with conductivity values of 2.5 to 4 {times} 10{sup {minus}2} (ohm-cm){sup {minus}1}. The matrix exhibits chemical stability against sodium for 100 hours at 250 to 300{degrees}C.
Date: July 17, 1990
Creator: Hash, M. C. & Bloom, I. D.
Partner: UNT Libraries Government Documents Department

Improved catalysts and method

Description: An improved catalyst and method for the oxyhydrochlorination of methane is disclosed. The catalyst includes a pyrogenic porous support on which is layered as active material, cobalt chloride in major proportion, and minor proportions of an alkali metal chloride and of a rare earth chloride. On contact of the catalyst with a gas flow of methane, HCl and oxygen, more than 60% of the methane is converted and of that converted more than 40% occurs as monochloromethane. Advantageously, the monochloromethane can be used to produce gasoline boiling range hydrocarbons with the recycle of HCl for further reaction. This catalyst is also of value for the production of formic acid as are analogous catalysts with lead, silver or nickel chlorides substituted for the cobalt chloride. 8 figs., 3 tabs.
Date: December 31, 1990
Creator: Taylor, C. E. & Noceti, R. P.
Partner: UNT Libraries Government Documents Department