164 Matching Results

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High power, high frequency, vacuum flange (open access)

High power, high frequency, vacuum flange

This invention is comprised of an improved waveguide flange is disclosed for high power operation that helps prevent arcs from being initiated at the junctions between waveguide sections. The flanges at the end of the waveguide sections have counterbores surrounding the waveguide tubes. When the sections are bolted together the counterbores form a groove that holds a fully annealed copper gasket. Each counterbore has a beveled step that is specially configured to insure the gasket forms a metal-to-metal vacuum seal without gaps or sharp edges. The resultant inner surface of the waveguide is smooth across the junctions between waveguide sections, and arcing is prevented.
Date: December 31, 1991
Creator: Felker, B. & McDaniel, M.
System: The UNT Digital Library
Method and apparatus for detecting timing errors in a system oscillator (open access)

Method and apparatus for detecting timing errors in a system oscillator

This invention is comprised of a method of detecting timing errors in a system oscillator for an electronic device, such as a power supply, includes the step of comparing a system oscillator signal with a delayed generated signal and generating a signal representative of the timing error when the system oscillator signal is not identical to the delayed signal. An LED indicates to an operator that a timing error has occurred. A hardware circuit implements the above-identified method.
Date: December 31, 1991
Creator: Gliebe, R. J. & Kramer, W. R.
System: The UNT Digital Library
Sequential cloning of chromosomes (open access)

Sequential cloning of chromosomes

A method for sequential cloning of chromosomal DNA and chromosomal DNA cloned by this method are disclosed. The method includes the selection of a target organism having a segment of chromosomal DNA to be sequentially cloned. A first DNA segment, having a first restriction enzyme site on either side. homologous to the chromosomal DNA to be sequentially cloned is isolated. A first vector product is formed by ligating the homologous segment into a suitably designed vector. The first vector product is circularly integrated into the target organism`s chromosomal DNA. The resulting integrated chromosomal DNA segment includes the homologous DNA segment at either end of the integrated vector segment. The integrated chromosomal DNA is cleaved with a second restriction enzyme and ligated to form a vector-containing plasmid, which is replicated in a host organism. The replicated plasmid is then cleaved with the first restriction enzyme. Next, a DNA segment containing the vector and a segment of DNA homologous to a distal portion of the previously isolated DNA segment is isolated. This segment is then ligated to form a plasmid which is replicated within a suitable host. This plasmid is then circularly integrated into the target chromosomal DNA. The chromosomal DNA containing …
Date: December 31, 1991
Creator: Lacks, Sanford A.
System: The UNT Digital Library
Dehydration of plutonium trichloride hydrate (open access)

Dehydration of plutonium trichloride hydrate

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, Jerry, Jr.; Avens, Larry R. & Trujillo, Eddie A.
System: The UNT Digital Library
Improved fuel cell system for transportation applications (open access)

Improved fuel cell system for transportation applications

This invention is comprised of a propulsion system for a vehicle having pairs of front and rear wheels and a fuel tank. An electrically driven motor having an output shaft operatively connected to at least one of said pair of wheels is connected to a fuel cell having a positive electrode and a negative electrode separated by an electrolyte for producing dc power to operate the motor. A partial oxidation reformer is connected both to the fuel tank and to the fuel cell receives hydrogen-containing fuel from the fuel tank and water and air and for partially oxidizing and reforming the fuel with water and air in the presence of an oxidizing catalyst and a reforming catalyst to produce a hydrogen-containing gas. The hydrogen-containing gas is sent from the partial oxidation reformer to the fuel cell negative electrode while air is transported to the fuel cell positive electrode to produce dc power for operating the electric motor.
Date: December 31, 1991
Creator: Kumar, Romesh; Ahmed, Shabbir; Krumpelt, Michael & Myles, Kevin M.
System: The UNT Digital Library
Machinable dissolved metal oxide superconductors (open access)

Machinable dissolved metal oxide superconductors

Powders of a metal oxide superconductor are mixed with sufficient amount (10--80 mol%) of In, Sn, and/or Al, to become nonbrittle, machinable. Preferred superconductors are YBa[sub 2]Cu[sub 3]O[sub 7[minus]x] and Bi-Sr-Ca-Cu-O compounds.
Date: January 1, 1991
Creator: Chen, Chung-Hsuan.
System: The UNT Digital Library
Plutonium recovery from spent reactor fuel by uranium displacement (open access)

Plutonium recovery from spent reactor fuel by uranium displacement

This report discusses a process for separating uranium values and transuranic values from fission products containing rare earth values when the values which are contained together in a molten chloride salt electrolyte. A molten chloride salt electrolyte with a first ratio of plutonium chloride to uranium chloride is contacted with both a solid cathode and an anode having values of uranium and fission products including plutonium. A voltage is applied across the anode and cathode electrolytically to transfer uranium and plutonium from the anode to the electrolyte while uranium values in the electrolyte electrolytically deposit as uranium metal on the solid cathode in an amount equal to the uranium and plutonium transferred from the anode causing the electrolyte to have a second ratio of plutonium chloride to uranium chloride. Then the solid cathode with the uranium metal deposited thereon is removed and molten cadmium having uranium dissolved therein is brought into contact with the electrolyte resulting in chemical transfer of plutonium values from the electrolyte to the molten cadmium and transfer of uranium values from the molten cadmium to the electrolyte until the first ratio of plutonium chloride to uranium chloride is re-established.
Date: January 1, 1991
Creator: Ackerman, J.P.
System: The UNT Digital Library
Containment system for supercritical water oxidation reactor (open access)

Containment system for supercritical water oxidation reactor

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.
System: The UNT Digital Library
Downhole material injector for lost circulation control (open access)

Downhole material injector for lost circulation control

This invention is comprised of an apparatus and method for simultaneously and separately emplacing two streams of different materials through a drillstring in a borehole to a downhole location for lost circulation control. The two streams are mixed outside the drillstring at the desired downhole location and harden only after mixing for control of a lost circulation zone.
Date: January 1, 1991
Creator: Glowka, David A.
System: The UNT Digital Library
Pneumatic solids feeder for coal gasification reactor (open access)

Pneumatic solids feeder for coal gasification reactor

This invention is comprised of a pneumatic feeder system for a coal gasification reactor which includes one or more feeder tubes entering the reactor above the level of the particle bed inside the reactor. The tubes are inclined downward at their outer ends so that coal particles introduced into the tubes through an aperture at the top of the tubes slides downward away from the reactor and does not fall directly into the reactor. Pressurized gas introduced into, or resulting from ignition of recycled combustible gas in a chamber adjacent to the tube ends, propels the coal from the tube into the reactor volume and onto the particle bed. Leveling of the top of the bed is carried out by a bladed rotor mounted on the reactor stirring shaft. Coal is introduced into the tubes from containers above the tubes by means of rotary valves placed across supply conduits. This system avoids placement of feeder hardware in the plenum above the particle bed and keeps the coal from being excessively heated prior to reaching the particle bed.
Date: December 31, 1991
Creator: Notestein, J. E. & Halow, J. S.
System: The UNT Digital Library
Electrical circuit for data reduction (open access)

Electrical circuit for data reduction

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 …
Date: December 31, 1991
Creator: Kronberg, J. W.
System: The UNT Digital Library
Coherence delay augmented laser beam homogenizer (open access)

Coherence delay augmented laser beam homogenizer

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.
System: The UNT Digital Library
Phase stable rf transport system (open access)

Phase stable rf transport system

This invention is comprised of an RF transport system which delivers a phase-stable RF signal to a load, such as an RF cavity of a charged particle accelerator. A circuit generates a calibration signal at an odd multiple frequency of the RF signal where the calibration signal is superimposed with the RF signal on a common cable that connects the RF signal with the load. Signal isolating diplexers are located at both the RF signal source end and load end of the common cable to enable the calibration to be inserted and extracted from the cable signals without any affect on the RF signal. Any phase shift in the calibration signal during traverse of the common cable is then functionally related to the phase shift in the RF signal. The calibration phase shift is used to control a phase shifter for the RF signal to maintain a stable RF signal at the load.
Date: February 19, 1991
Creator: Curtin, M. T.; Natter, E. F. & Denney, P. M.
System: The UNT Digital Library
Process for strengthening silicon based ceramics (open access)

Process for strengthening silicon based ceramics

A process for strengthening silicon based ceramic monolithic materials and composite materials that contain silicon based ceramic reinforcing phases that requires that the ceramic be exposed to a wet hydrogen atmosphere at about 1400{degrees}C. The process results in a dense, tightly adherent silicon containing oxide layer that heals, blunts, or otherwise negates the detrimental effect of strength limiting flaws on the surface of the ceramic body.
Date: March 7, 1991
Creator: Kim, Hyoun-Ee & Moorhead, A. J.
System: The UNT Digital Library
Moist caustic leaching of coal (open access)

Moist caustic leaching of coal

A process is claimed for reducing the sulfur and ash content of coal. Particulate coal is introduced into a closed heated reaction chamber having an inert atmosphere to which is added moist caustic having a water content in the range of from about 15% by weight to about 35% by weight. The coal and moist caustic are kept at a temperature of about 300{degrees}C. Then, water is added to the coal and caustic mixture to form an aqueous slurry, which is washed with water to remove caustic from the coal and to produce an aqueous caustic solution. Water is evaporated from the aqueous caustic solution until the water is in the range of from about 15% by weight to about 35% by weight and is reintroduced to the closed reaction chamber. Sufficient acid is added to the washed coal slurry to neutralize any remaining caustic present on the coal, which is thereafter dried to produce desulfurized coal having not less than about 90% by weight of the sulfur present in the coal feed removed and having an ash content of less than about 2% by weight.
Date: December 31, 1991
Creator: Nowak, M. A.
System: The UNT Digital Library
Precision surface machining (open access)

Precision surface machining

Precision finishing apparatus utilizing line contact polishing to produce optical quality parts. A rotatable cylinder is horizontally disposed above a workpiece which is mounted on a rotatable, and horizontally and vertically adjustable chuck. Predetermined surfaces can be cut into the surface of the cylinder to produce figures of revolution, such as aspheres,, when the workpiece is being rotated.
Date: March 6, 1991
Creator: Lazazzera, Vito J. & Schmell, Rodney A.
System: The UNT Digital Library
Oil/gas separator for installation at burning wells (open access)

Oil/gas separator for installation at burning wells

An oil/gas separator is disclosed that can be utilized to return the burning wells in Kuwait to production. Advantageously, a crane is used to install the separator at a safe distance from the well. The gas from the well is burned off at the site, and the oil is immediately pumped into Kuwait`s oil gathering system. Diverters inside the separator prevent the oil jet coming out of the well from reaching the top vents where the gas is burned. The oil falls back down, and is pumped from an annular oil catcher at the bottom of the separator, or from the concrete cellar surrounding the well.
Date: December 31, 1991
Creator: Alonso, C. T.; Bender, D. A. & Bowman, B. R.
System: The UNT Digital Library
Duplex sampling apparatus and method (open access)

Duplex sampling apparatus and method

An improved apparatus is provided for sampling a gaseous mixture and for measuring mixture components. The apparatus includes two sampling containers connected in series serving as a independently determine the amounts of condensable and noncondensable gases in admixture from a single sample. More specifically, a first container includes a first port capable of selectively connecting to and disconnecting from a sample source and a second port capable of selectively connecting to and disconnecting from a second container. A second container also includes a first port capable of selectively connecting to and disconnecting from the second port of the first container and a second port capable of either selectively connecting to and disconnecting from a differential pressure source. By cooling a mixture sample in the first container, the condensable vapors form a liquid, leaving noncondensable gases either as free gases or dissolved In the liquid. The condensed liquid is heated to drive out dissolved noncondensable gases, and all the noncondensable gases are transferred to the second container. Then the first and second containers are separated from one another in order to separately determine the amount of noncondensable gases and the amount of condensable gases in the sample.
Date: January 30, 1991
Creator: Brown, P. E. & Lloyd, R.
System: The UNT Digital Library
Vanadium-pumped titanium x-ray laser (open access)

Vanadium-pumped titanium x-ray laser

A resonantly photo-pumped x-ray laser is formed of a vanadium and titanium foil combination that is driven by two beams of intense line focused optical laser radiation. Ground state neon-like titanium ions are resonantly photo-pumped by line emission from fluorine-like vanadium ions.
Date: February 13, 1991
Creator: Nilsen, J.
System: The UNT Digital Library
Regenerable activated bauxite adsorbent alkali monitor probe (open access)

Regenerable activated bauxite adsorbent alkali monitor probe

This invention relates to a regenerable activated bauxite adsorber alkali monitor probe for field applications to provide reliable measurement of alkali-vapor 5 concentration in combustion gas with special emphasis on pressurized fluidized-bed combustion (PFBC) off-gas. More particularly, the invention relates to the development of a easily regenerable bauxite adsorbent for use in a method to accurately determine the alkali-vapor content of PFBC 10 exhaust gases.
Date: January 22, 1991
Creator: Lee, S. H. D.
System: The UNT Digital Library
Actinide halide complexes (open access)

Actinide halide complexes

A compound of the formula MX{sub n}L{sub m} wherein M = Th, Pu, Np,or Am thorium, X = a halide atom, n = 3 or 4, L is a coordinating ligand selected from the group consisting of aprotic Lewis bases having an oxygen-, nitrogen-, sulfur-, or phosphorus-donor, and m is 3 or 4 for monodentate ligands or is 2 for bidentate ligands, where n + m = 7 or 8 for monodentate ligands or 5 or 6 for bidentate ligands, a compound of the formula MX{sub n} wherein M, X, and n are as previously defined, and a process of preparing such actinide metal compounds including admixing the actinide metal in an aprotic Lewis base as a coordinating solvent in the presence of a halogen-containing oxidant, are provided.
Date: February 7, 1991
Creator: Avens, Larry R.; Zwick, Bill D.; Sattelberger, Alfred P.; Clark, David L. & Watkin, J. G.
System: The UNT Digital Library
Pulse combustor with controllable oscillations (open access)

Pulse combustor with controllable oscillations

A pulse combustor having thermally induced pulse combustion in a continuously flowing system is described. The pulse combustor is fitted with at lease one elongated ceramic body which significantly increases the heat transfer area in the combustion chamber of the combustor. The ceramic body or bodies possess sufficient mass and heat capacity to ignite the fuel-air charge once the ceramic body or bodies are heated by conventional spark plug initiated combustion so as to provide repetitive ignition and combustion of sequentially introduced fuel-air charges without the assistance of the spark plug and the rapid quenching of the flame after each ignition in a controlled manner so as to provide a selective control over the oscillation frequency and amplitude. Additional control over the heat transfer in the combustion chamber is provided by employing heat exchange mechanisms for selectively heating or cooling the elongated ceramic body or bodies and/or the walls of the combustion chamber.
Date: December 31, 1991
Creator: Richards, G. A.; Morris, G. J. & Welter, M. J.
System: The UNT Digital Library
Chemotactic selection of pollutant degrading soil bacteria (open access)

Chemotactic selection of pollutant degrading soil bacteria

A method is described for identifying soil microbial strains which may be bacterial degraders of pollutants. This method includes: Placing a concentration of a pollutant in a substantially closed container; placing the container in a sample of soil for a period of time ranging from one minute to several hours; retrieving the container and collecting its contents; microscopically determining the identity of the bacteria present. Different concentrations of the pollutant can be used to determine which bacteria respond to each concentration. The method can be used for characterizing a polluted site or for looking for naturally occurring biological degraders of the pollutant. Then bacteria identified as degraders of the pollutant and as chemotactically attracted to the pollutant are used to innoculate contaminated soil. To enhance the effect of the bacteria on the pollutant, nutrients are cyclicly provided to the bacteria then withheld to alternately build up the size of the bacterial colony or community and then allow it to degrade the pollutant.
Date: March 4, 1991
Creator: Hazen, T. C.
System: The UNT Digital Library
Amorphous silicon/polycrystalline thin film solar cells (open access)

Amorphous silicon/polycrystalline thin film solar cells

An improved photovoltaic solar cell is described including a p-type amorphous silicon layer, intrinsic amorphous silicon, and an n-type polycrystalline semiconductor such as cadmium sulfide, cadmium zinc sulfide, zinc selenide, gallium phosphide, and gallium nitride. The polycrystalline semiconductor has an energy bandgap greater than that of the amorphous silicon. The solar cell can be provided as a single-junction device or a multijunction device.
Date: March 13, 1991
Creator: Ullal, H. S.
System: The UNT Digital Library