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All ceramic structure for molten carbonate fuel cell

Description: An all-ceramic molten carbonate fuel cell having a composition formed of a multivalent metal oxide or oxygenate such as an alkali metal, transition metal oxygenate. The structure includes an anode and cathode separated by an electronically conductive interconnect. The electrodes and interconnect are compositions ceramic materials. Various combinations of ceramic compositions for the anode, cathode and interconnect are disclosed. The fuel cell exhibits stability in the fuel gas and oxidizing environments. It presents reduced sealing and expansion problems in fabrication and has improved long-term corrosion resistance.
Date: December 31, 1991
Creator: Smith, James L. & Kucera, Eeugenia H.
Partner: UNT Libraries Government Documents Department

Apparatus for generating a robotic plan for automatically assembling a mechanical component

Description: This invention is comprised of an apparatus operable in combination with a robot positioned in a workcell having a preselected specification is operable to generate a program for operating the robot to assemble a mechanical component. The apparatus includes a planner for receiving as inputs a CAD model of the mechanical component to be assembled, a set of robot primitives and a set of mechanical component assembly rules for determining the conditions under which the set of robot primitives apply. The planner generates from these inputs a general, workcell specification-independent plan for assembling the mechanical component. The general plan generated by the planner is provided as an input to a compiler along with details relating to the workcell specification, and the compiler generates from these inputs a workcell specification-dependent program which operates the robot to assemble the mechanical component.
Date: December 31, 1991
Creator: Maciejewski, A. A. & Strip, D. R.
Partner: UNT Libraries Government Documents Department

Apparatus for preventing particle deposition from process streams on optical access windows

Description: This invention is comprised of an electrostatic precipitator that is disposed inside and around the periphery of the window of a viewing port communicating with a housing through which a particle-laden gas stream is being passed. The precipitator includes a pair of electrodes around the periphery of the window, spaced apart and connected to a unidirectional voltage source. Application of high voltage from the source to the electrodes causes air molecules in the gas stream to become ionized, attaching to solid particles and causing them to be deposited on a collector electrode. This prevents the particles from being deposited on the window and keeps the window clean for viewing and making optical measurements.
Date: December 31, 1991
Creator: Logan, R.G. & Grimm, U.
Partner: UNT Libraries Government Documents Department

Automated robotic equipment for ultrasonic inspection of pressurizer heater wells

Description: A robotic device for remotely inspecting pressurizer heater wells is provided which has the advantages of quickly, precisely, and reliably acquiring data at reasonable cost while also reducing radiation exposure of an operator. The device comprises a probe assembly including a probe which enters a heater well, gathers data regarding the condition of the heater well and transmits a signal carrying that data; a mounting device for mounting the probe assembly at the opening of the heater well so that the probe can enter the heater well; a first motor mounted on the mounting device for providing movement of the probe assembly in an axial direction; and a second motor mounted on the mounting device for providing rotation of the probe assembly. This arrangement enables full inspection of the heater well to be carried out.
Date: December 31, 1991
Creator: Nachbar, H.D.; DeRossi, R.S. & Mullins, L.E.
Partner: UNT Libraries Government Documents Department

Ceramic composite coatings

Description: A thin, room-temperature-curing, ceramic composite for coating and patching metal substrates comprises a sol gel silica glass matrix filled with finely ground particles or fibers, preferably alumina. The sol gel glass is made by adding ethanol to water to form a first mixture, then separately adding ethanol to tetraethyl orthosilicate to form a second mixture, then slowly adding the first to the second mixture to make a third mixture, and making a slurry by adding the finely ground particles or fibers to the third mixture. The composite can be applied by spraying, brushing or trowelling. If applied to patch fine cracks, densification of the ceramic composite may be obtained to enhance sealing by applying heat during curing.
Date: December 31, 1991
Creator: Wicks, G.G.
Partner: UNT Libraries Government Documents Department

Ceramic tamper-revealing seals

Description: A tamper resistant seal is made of a brittle material with internal defects internally arranged in a random pattern to form a unique fingerprint characteristic of the seal which may be identified by ultrasonic scanning to determine whether tampering has occurred. It comprises a flexible metal or ceramic cable with composite ceramic ends or a U-shaped ceramic connecting element attached to a binding element plate or block cast from alumina or Zr, and connected to the connecting element by shrink fitting. Part of the binding element is cast with NiO{sub 2} particles, which allows ultrasonic scanning and the resulting fingerprint. 7 figs.
Date: December 31, 1991
Creator: Kupperman, D. S.; Raptis, A. C. & Sheen, Shuh-Haw
Partner: UNT Libraries Government Documents Department

Cesium iodide alloys

Description: 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: December 31, 1991
Creator: Kim, Hyoun-Ee & Moorhead, A. J.
Partner: UNT Libraries Government Documents Department

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

Description: 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.
Partner: UNT Libraries Government Documents Department

Coherence delay augmented laser beam homogenizer

Description: It is an object of the present invention to provide an apparatus that can reduce the apparent coherence length of a laser beam so the beam can be used with an inexpensive homogenizer to produce an output beam with a uniform spatial intensity across its entire cross section. It is a further object of the invention to provide an improved homogenizer with a variable aperture size that is simple and easily made. It is still an additional object of the invention to provide an improved liquid filled homogenizer utilizing total internal reflection for improved efficiency. These, and other objects of the invention are realized by using a ``coherence delay line,`` according to the present invention, in series between a laser and a homogenizer. The coherence delay line is an optical ``line`` that comprises two mirrors, one partially reflecting, and one totally reflecting, arranged so that light incident from the laser first strikes the partially reflecting mirror. A portion of the beam passes through, and a portion is reflected back to the totally reflecting mirror.
Date: December 31, 1991
Creator: Rasmussen, P. & Bernhardt, A.
Partner: UNT Libraries Government Documents Department

Combined transuranic-strontium extraction process

Description: The transuranic (TRU) elements neptunium, plutonium and amercium can be separated together with strontium from nitric acid waste solutions in a single process. An extractant solution of a crown ether and an alkyl(phenyl)-N.N-dialkylcarbanylmethylphosphine oxide in an appropriate diluent will extract the TRU`s to gather with strontium, uranium and technetium. The TRU`s and the strontium can then be selectively stripped from the extractant for disposal.
Date: December 31, 1991
Creator: Horwitz, E. P. & Dietz, M. L.
Partner: UNT Libraries Government Documents Department

Compact acoustic refrigerator

Description: This invention is comprised of a compact acoustic refrigeration system that actively cools components, e.g., electrical circuits, in a borehole environment. An acoustic engine includes first thermodynamic elements for generating a standing acoustic wave in a selected medium. An acoustic refrigerator includes second thermodynamic elements located in the standing wave for generating a relatively cold temperature at a first end of the second thermodynamic elements and a relatively hot temperature at a second end of the second thermodynamic elements. A resonator volume cooperates with the first and second thermodynamic elements to support the standing wave. To accommodate the high heat fluxes required for heat transfer to/from the first and second thermodynamic elements, first heat pipes transfer heat from the heat load to the second thermodynamic elements and second heat pipes transfer heat from first and second thermodynamic elements to the borehole environment.
Date: December 31, 1991
Creator: Bennett, G. A.
Partner: UNT Libraries Government Documents Department

Containment system for supercritical water oxidation reactor

Description: This invention is comprised of a system for containment of a supercritical water oxidation reactor in the event of a rupture of the reactor. The system includes a containment for housing the reaction vessel and a communicating chamber for holding a volume of coolant, such as water. The coolant is recirculated and sprayed to entrain and cool any reactants that might have escaped from the reaction vessel. Baffles at the entrance to the chamber prevent the sprayed coolant from contacting the reaction vessel. An impact-absorbing layer is positioned between the vessel and the containment to at least partially absorb momentum of any fragments propelled by the rupturing vessel. Remote, quick-disconnecting fittings exterior to the containment, in cooperation with shut-off valves, enable the vessel to be isolated and the system safely taken off-line. Normally-closed orifices throughout the containment and chamber enable decontamination of interior surfaces when necessary.
Date: December 31, 1991
Creator: Chastagner, P.
Partner: UNT Libraries Government Documents Department

Crystalline titanate catalyst supports

Description: A series of new crystalline titanates (CT) are shown to have considerable potential as catalyst supports. For Pd supported catalyst, the catalytic activity for pyrene hydrogenation was substantially different depending on the type of CT, and one was substantially more active than Pd on hydrous titanium oxide (HTO). For 1-hexene hydrogenation the activities of the new CTs were approximately the same as for the hydrous metal oxide supports.
Date: December 31, 1991
Creator: Anthony, Rayford G. & Dosch, Robert G.
Partner: UNT Libraries Government Documents Department

Dehydration of plutonium trichloride hydrate

Description: A process of preparing anhydrous actinide metal trichlorides of plutonium or neptunium by reacting an aqueous solution of an actinide metal trichloride selected from the group consisting of plutonium trichloride or neptunium trichloride with a reducing agent capable of converting the actinide metal from an oxidation state of +4 to +3 in a resultant solution, evaporating essentially all the solvent from the resultant solution to yield an actinide trichloride hydrate material, dehydrating the actinide trichloride hydrate material by heating the material in admixture with excess thionyl chloride, and recovering anhydrous actinide trichloride is provided.
Date: December 31, 1991
Creator: Foropoulos, J. Jr.; Avens, L.R. & Trujillo, E.A.
Partner: UNT Libraries Government Documents Department

A device for the determination of low concentrations of oxygen in carbonaceous materials

Description: Oxygen in carbonaceous materials is converted to carbon monoxide (CO) by pyrolyzing the material in a stream of oxygen-free helium. The CO is reacted with Ni{sup 63}, a radioactive isotope of nickel, to form nickel tetracarbanyl (Ni{sup 63}(CO){sub 4}) which is carried by the helium stream into a flow-through gas proportional counter. The quantity of Ni(CO){sub 4} is determined by the radioactivity of the gas as measured by the gas proportional counter. After exiting the flow through counter the Ni{sub 63}(CO){sub 4} is destroyed by exposing it to high temperatures. The Ni{sub 63} is retained within the apparatus while the CO is flushed from the system after being oxidized to carbon dioxide (CO{sub 2}). The detection limit is estimated to be less than 1 part per billion oxygen for a 10 mg sample.
Date: December 31, 1991
Creator: Schultz, H.
Partner: UNT Libraries Government Documents Department

Electrical circuit for data reduction

Description: This invention is comprised of an electrical circuit for determining characteristic voltages, such as maximum, minimum, average and root mean squared voltages, of a time-varying electrical signal. The circuit comprises a positive and a negative peak detector that feed the positive and negative voltage peaks detected in each of a series of time intervals into a solid-state multiplexer controlled by a process controller. The time intervals are generated by the process controller in combination with a clocking, circuit. The multiplexer applies the positive and negative peak voltages to a set of four capacitors, apply the positive peak to one capacitor during one interval and then the negative peak to that capacitor in a subsequent interval so that each capacitor is alternatingly accumulating a positive peak then a negative peak to obviate the need for resetting each capacitor. After the positive peak voltage is applied to one capacitor, the connection is switched during the next interval for reading the negative peak voltage, then switched again for applying, a negative peak voltage, then switched once more for reading the negative peak voltage, the multiplexer serving, as a solid state commutator for switching the electrical connection. Alternatively, peak maximum and minimum voltage detectors may be replaced with circuitry designed to obtain the additional characteristic voltages desired in each interval.
Date: December 31, 1991
Creator: Kronberg, J. W.
Partner: UNT Libraries Government Documents Department

Electrowinning process with electrode compartment to avoid contamination of electrolyte

Description: An electrolytic process and apparatus for reducing calcium oxide in a molten electrolyte of CaCl{sub 2}-CaF{sub 2} with a graphite anode in which particles or other contamination from the anode is restricted by the use of a porous barrier in the form of a basket surrounding the anode which may be removed from the electrolyte to burn the graphite particles, and wherein the calcium oxide feed is introduced to the anode compartment to increase the oxygen ion concentration at the anode.
Date: December 31, 1991
Creator: Poa, D.S.; Pierce, R.D.; Mulcahey, T.P. & Johnson, G.K.
Partner: UNT Libraries Government Documents Department

Energetic composites and method of providing chemical energy

Description: A method for providing chemical energy and energetic compositions of matter consisting of thin layers of substances which will exothermically react with one another. The layers of reactive substances are separated by thin layers of a buffer material which prevents the reactions from taking place until the desired time. The reactions are triggered by an external agent, such as mechanical stress or an electric spark. The compositions are known as metastable interstitial composites (MICs). This class of compositions includes materials which have not previously been capable of use as energetic materials. The speed and products of the reactions can be varied to suit the application.
Date: December 31, 1991
Creator: Danen, W.C. & Martin, J.A.
Partner: UNT Libraries Government Documents Department

Expansion joint for guideway for magnetic levitation transportation system

Description: An expansion joint that allows a guideway of a magnetic levitation transportation system to expand and contract while minimizing transients occurring in the magnetic lift and drag forces acting on a magnetic levitation vehicle traveling over the joint includes an upper cut or recess extending downwardly from the upper surface of the guideway and a non-intersecting lower cut or recess that extends upwardly from the lower surface of the guideway. The sidewalls of the cuts can be parallel to each other and the vertical axis of the guideway; the depth of the lower cut can be greater than the depth of the upper cut; and the overall combined lengths of the cuts can be greater than the thickness of the guideway from the upper to lower surface so that the cuts will overlap, but be spaced apart from each other. The distance between the cuts can be determined on the basis of the force transients and the mechanical behavior of the guideway. A second pair of similarly configured upper and lower cuts may be disposed in the guideway; the expansion joint may consist of two upper cuts and one lower cut; or the cuts may have non-parallel, diverging sidewalls so that the cuts have a substantially dove-tail shape.
Date: December 31, 1991
Creator: Rossing, T.D.
Partner: UNT Libraries Government Documents Department

An expert system for analyzing eddy current measurements

Description: A method and apparatus (called DODGER) analyzes eddy current data for heat exchanger tubes or any other metallic object. DODGER uses an expert system to analyze eddy current data by reasoning with uncertainty and pattern recognition. The expert system permits, DODGER to analyze eddy current data intelligently, an obviate operator uncertainty by analyzing the data in a uniform and consistent manner.
Date: December 31, 1991
Creator: Levy, Arthur J.; Oppenlander, Jane E.; Brudnoy, David M.; Englund, James M. & Loomis, Kent C.
Partner: UNT Libraries Government Documents Department

Fading channel simulator

Description: This invention relates to high frequency (HF) radio signal propagation through fading channels and, more particularly, to simulation of fading channels in order to characterize HF radio system performance in transmitting and receiving signals through such fading channels. Fading channel effects on a transmitted communication signal are simulated with both frequency and time variations using a channel scattering function to affect the transmitted signal. A conventional channel scattering function is converted to a series of channel realizations by multiplying the square root of the channel scattering function by a complex number of which the real and imaginary parts are each independent variables. The two-dimensional inverse-FFT of this complex-valued channel realization yields a matrix of channel coefficients that provide a complete frequency-time description of the channel. The transmitted radio signal is segmented to provide a series of transmitted signal and each segment is subject to FFT to generate a series of signal coefficient matrices. The channel coefficient matrices and signal coefficient matrices are then multiplied and subjected to inverse-FFT to output a signal representing the received affected radio signal. A variety of channel scattering functions can be used to characterize the response of a transmitter-receiver system to such atmospheric effects.
Date: December 31, 1991
Creator: Argo, P.E. & Fitzgerald, T.J.
Partner: UNT Libraries Government Documents Department

Fail-safe storage rack for fuel rod assemblies

Description: This report discusses a fail-safe storage rack which is provided for interim storage of spent but radioactive nuclear fuel rod assemblies. The rack consists of a checkerboard array of substantially square, elongate receiving tubes fully enclosed by a double walled container, the outer wall of which is imperforate for liquid containment and the inner wall of which is provided with perforations for admitting moderator liquid flow to the elongate receiving tubes, the liquid serving to take up waste heat from the stored nuclear assemblies and dissipate same to the ambient liquid reservoir. A perforated cover sealing the rack facilitates cooling liquid entry and dissipation.
Date: December 31, 1991
Creator: Lewis, D. R.
Partner: UNT Libraries Government Documents Department

Free-standing superconductive articles

Description: A substrate-free, free-standing epitaxially oriented superconductive film including a layer of a template material and a layer of a ceramic superconducting material is provided together with a method of making such a substrate-free ceramic superconductive film by coating an etchable material with a template layer, coating the template layer with a layer of a ceramic superconductive material, coating the layer of ceramic superconductive material with a protective material, removing the etchable material by an appropriate means so that the etchable material is separated from a composite structure including the template layer, the ceramic superconductive material layer and the protective material layer, removing the protective material layer from the composite structure whereby a substrate-free, free-standing ceramic superconductive film remains.
Date: December 31, 1991
Creator: Wu, X.D. & Muenchausen, R.E.
Partner: UNT Libraries Government Documents Department

High performance static latches with complete single event upset immunity

Description: This invention is comprised of a logical memory latch and cell, using logic and circuit modifications, provides SEU immunity without loss of speed. A single logic state is hardened against SEU using technology methods and the information concerning valid states is then based to simplify hardened circuit design.
Date: December 31, 1991
Creator: Corbett, W.T. & Weaver, H.T.
Partner: UNT Libraries Government Documents Department