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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

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

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

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

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

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

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

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

Improved morphology in electrochemically grown conducting polymer films

Description: A conducting polymer film with an improved space filling is formed on a metal electrode surface. A self-assembling monolayer is formed directly on the metal surface where the monolayer has a first functional group that binds to the metal surface and a second chemical group that forms a chemical bonding site for molecules forming the conducting polymer. The conducting polymer is then conventionally deposited by electrochemical deposition. In one example, a conducting film of polyaniline is formed on a gold electrode surface with an intermediate monolayer of p-aminothiophenol.
Date: December 31, 1990
Creator: Rubinstein, I.; Gottesfeld, S. & Sabatani, E.
Partner: UNT Libraries Government Documents Department

Improved thermal storage module for solar dynamic receivers

Description: This invention relates to a thermal storage apparatus and more particularly to an apparatus for use in conjunction with solar dynamic energy storage systems. The invention is comprised of a thermal energy storage system comprising a germanium phase change material and a graphite container.
Date: December 31, 1990
Creator: Beatty, R. L. & Lauf, R. J.
Partner: UNT Libraries Government Documents Department

A method and apparatus for continuous electrophoresis

Description: A method and apparatus for conducting continuous separation of substances by electrophoresis are disclosed. The process involves electrophoretic separation combined with couette flow in a thin volume defined by opposing surfaces. By alternating the polarity of the applied potential and producing reciprocating short rotations of at least on of the surfaces relative to the other, small increments of separation accumulate to cause substantial, useful segregation of electrophoretically separable components in a continuous flow system.
Date: December 31, 1990
Creator: Watson, J. S.
Partner: UNT Libraries Government Documents Department

Method for Improving the Growth of Cadmium Telluride on a Gallium Arsenide Substrate

Description: A method for preparing a gallium arsenide substrate, prior to growing a layer of cadmium telluride on a support surface thereof. The preparation includes the steps of cleaning the gallium arsenide substrate and thereafter forming prepatterned shapes on the support surface of the gallium arsenide substrate. The layer of cadmium telluride then grown on the prepared substrate results in dislocation densities of approximately 1{times}10{sup 6}/cm{sup 2} or less. The prepatterned shapes on the support surface of the gallium arsenide substrate are formed by reactive ion etching an original outer surface of the gallium arsenide substrate and into the body of the gallium arsenide substrate to a depth of at least two microns. The prepatterned shapes have the appearance of cylindrical mesas each having a diameter of at lease twelve microns. After the mesas are formed on the support surface of the gallium arsenide substrate, the substrate is again cleaned.
Date: December 31, 1990
Creator: Reno, John L.
Partner: UNT Libraries Government Documents Department

A method for joining ceramic shapes

Description: The invention is a method for joining shapes of ceramic materials together to form a unitary ceramic structure. In the method of the invention, a mixture of two or more chemical components which will react exothermically is placed between the surfaces to be joined, and the joined shapes heated to a temperature sufficient to initiate the exothermic reaction forming a joining material which acts to bond the shapes together. Reaction materials are chosen which will react exothermically at temperatures below the degradation temperature of the materials to be joined. The process is particularly suited for joining composite materials of the silicon carbide-silicon carbide fiber type.
Date: December 31, 1990
Creator: Rabin, B. H.
Partner: UNT Libraries Government Documents Department

Method of recovering hazardous waste from phenolic resin filters

Description: A method has been found for treating phenolic resin filter, whereby the filter is solubilized within the filter cartridge housing so the filter material can be removed from the cartridge housing in a remote manner. The invention consists of contacting the filter within the housing with an aqueous solution of about 8 to 12M nitric acid, at a temperature from about 110 to 190{degree}F, maintaining the contact for a period of time sufficient to solubilize the phenolic material within the housing, and removing the solubilized phenolic material from the housing, thereby removing the filter cartridge from the housing. Any hazardous or other waste material can then be separated from the filter material by chemical or other means.
Date: December 31, 1990
Creator: Meikrantz, David H.; Bourne, Gary L.; McFee, John N.; Burdge, Bradley G. & McConnell, John W., Jr.
Partner: UNT Libraries Government Documents Department

Method of separating organic contaminants from fluid feedstreams with polyphosphazene membranes

Description: A method is provided for separating polar hydrocarbons from a fluid feedstream. The fluid feedstream is flowed across a first surface of a polyphosphazene semipermeable membrane. At least one polar hydrocarbon from the fluid feedstream permeates through the polyphosphazene semipermeable membrane to a second opposed surface of the semipermeable membrane. Then the permeated polar hydrocarbon is removed from the second opposed surface of the polyphosphazene semipermeable membrane. Outstanding and unexpected separation selectivities on the order of 10,000 were obtained for methylene chloride when a methylene chloride in water feedstream was flowed across the polyphosphazene semipermeable membrane in the invented method.
Date: December 31, 1990
Creator: McCaffrey, R. R. & Cummings, D. G.
Partner: UNT Libraries Government Documents Department

Passive decay heat removal system for water-cooled nuclear reactors

Description: This document describes passive decay-heat removal system for a water-cooled nuclear reactor which employs a closed heat transfer loop having heat-exchanging coils inside an open-topped, insulated evaporator located inside the reactor vessel, below its normal water level, in communication with a condenser located outside of containment and exposed to the atmosphere. The heat transfer loop is located such that the evaporator is in a position where, when the water level drops in the reactor, it will become exposed to steam. Vapor produced in the evaporator passes upward to the condenser above the normal water level. In operation, condensation in the condenser removes heat from the system, and the condensed liquid is returned to the evaporator. The system is disposed such that during normal reactor operations where the water level is at its usual position, very little heat will be removed from the system, but during emergency, low water level conditions, substantial amounts of decay heat will be removed.
Date: December 31, 1990
Creator: Forseberg, C. W.
Partner: UNT Libraries Government Documents Department

Phosphazene polymer containing composites and method for making phosphazene polymer containing composites

Description: The object of the invention is to provide a composite material comprised of phosphazene polymer. A feature of phosphazene-containing composites is their superior stiffness, thermal stability, and hardness which is lacking in more typical composite constituents. An advantage of using phosphazene composites is a wider range of applications, including uses in harsh environments. Another object of the present invention provides a method for producing phosphazene-containing composite materials through a pultrusion process. In brief, these and other objects are achieved by a composite produced by first coating a reinforcing material with an inorganic phosphazene compound and then polymerizing the phosphazene compound so as to confer superior thermal, physical and chemical resistance qualities to the composite. 2 figs., 6 tabs.
Date: December 31, 1990
Creator: Allen, C. A.; Grey, A. E.; McCaffrey, R. R.; Simpson, B. M. & Stone, M. L.
Partner: UNT Libraries Government Documents Department

Plenum type crystal growth chamber

Description: Crystals are grown in a tank which is divided by a baffle into a crystal growth region above the baffle and a plenum region below the baffle. A turbine blade or stirring wheel is positioned in a turbine tube which extends through the baffle to generate a flow of solution from the crystal growing region to the plenum region. The solution is pressurized as it flows into the plenum region. The pressurized solution flows back to the crystal growing region through return flow tubes extending through the baffle. Growing crystals are positioned near the ends of the return flow tubes to receive a direct flow of solution.
Date: December 31, 1990
Creator: Montgomery, K. E.
Partner: UNT Libraries Government Documents Department

Precision wire feeder for small diameter wire

Description: This invention is comprised of a device for feeding small diameter wire having a diameter less than .04 mm (16 mil) to a welding station which includes a driving wheel for controllably applying a non-deforming driving force to the wire to move the free end of the wire towards the welding station; and a tension device such as a torque motor for constantly applying a reverse force to the wire in opposition to the driving force to keep the wire taut. 1 fig.
Date: December 31, 1990
Creator: Brandon, E. D.; Hooper, F. M. & Reichenbach, M. L.
Partner: UNT Libraries Government Documents Department

Preparation of high specific activity technetium-96

Description: The present invention relates to a method of producing Tc-96 from the proton irradiation of a rhodium target and a technique for isolating under remote hot cell conditions the Tc-96 from the proton irradiated target.
Date: December 31, 1990
Creator: Mausner, L. F.; Srivastava, S. C. & Prach, T.
Partner: UNT Libraries Government Documents Department

Process and apparatus for coal hydrogenation

Description: In a coal liquefaction process an aqueous slurry of coal is prepared containing a dissolved liquefaction catalyst. A small quantity of oil is added to the slurry and then coal-oil agglomerates are prepared by agitation of the slurry at atmospheric pressure. The resulting mixture is drained of excess water and dried at atmospheric pressure leaving catalyst deposited on the agglomerates. The agglomerates then are fed to an extrusion device where they are formed into a continuous ribbon of extrudate and fed into a hydrogenation reactor at elevated pressure and temperature. The catalytic hydrogenation converts the extrudate primarily to liquid hydrocarbons in the reactor. The liquid drained in recovering the agglomerates is recycled. 1 fig.
Date: December 31, 1990
Creator: Ruether, J. A. & Simpson, T. B.
Partner: UNT Libraries Government Documents Department