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Drum bubbler tritium processing system (open access)

Drum bubbler tritium processing system

A method is described for separating tritium oxide from a gas stream containing tritium oxide. The gas stream containing tritium oxide is fed into a container of water having a head space above the water. Bubbling the gas stream containing tritium oxide through the container of water and removing gas from the container head space above the water. Thereafter, the gas from the head space is dried to remove water vapor from the gas, and the water vapor is recycled to the container of water.
Date: December 1, 1998
Creator: Rule, Keith; Gettelfinger, Geoff & Kivler, Paul
System: The UNT Digital Library
Fatty acyl-CoA reductase (open access)

Fatty acyl-CoA reductase

The present invention relates to bacterial enzymes, in particular to an acyl-CoA reductase and a gene encoding an acyl-CoA reductase, the amino acid and nucleic acid sequences corresponding to the reductase polypeptide and gene, respectively, and to methods of obtaining such enzymes, amino acid sequences and nucleic acid sequences. The invention also relates to the use of such sequences to provide transgenic host cells capable of producing fatty alcohols and fatty aldehydes.
Date: December 1, 1998
Creator: Reiser, Steven E. & Somerville, Chris R.
System: The UNT Digital Library
Nanodisperse transition metal electrodes (NTME) for electrochemical cells (open access)

Nanodisperse transition metal electrodes (NTME) for electrochemical cells

Disclosed are transition metal electrodes for electrochemical cells using gel-state and solid-state polymers. The electrodes are suitable for use in primary and secondary cells. The electrodes (either negative electrode or positive electrode) are characterized by uniform dispersion of the transition metal at the nanoscale in the polymer. The transition metal moiety is structurally amorphous, so no capacity fade should occur due to lattice expansion/contraction mechanisms. The small grain size, amorphous structure and homogeneous distribution provide improved charge/discharge cycling performance, and a higher initial discharge rate capability. The cells can be cycled at high current densities, limited only by the electrolyte conductivity. A method of making the electrodes (positive and negative), and their usage in electrochemical cells are disclosed.
Date: December 1, 1998
Creator: Striebel, Kathryn A. & Wen, Shi-Jie
System: The UNT Digital Library
Oxide strengthened molybdenum-rhenium alloy (open access)

Oxide strengthened molybdenum-rhenium alloy

Provided is a method of making an ODS molybdenum-rhenium alloy which includes the steps of: (1) forming a slurry containing molybdenum oxide and a metal salt dispersed in an aqueous medium, the metal salt being selected from nitrates or acetates of lanthanum, cerium or thorium; (2) heating the slurry in the presence of hydrogen to form a molybdenum powder comprising molybdenum and an oxide of the metal salt; (3) mixing rhenium powder with the molybdenum powder to form a molybdenum-rhenium powder; (4) pressing the molybdenum-rhenium powder to form a molybdenum-rhenium compact; (5) sintering the molybdenum-rhenium compact in hydrogen or under a vacuum to form a molybdenum-rhenium ingot; and (6) compacting the molybdenum-rhenium ingot to reduce the cross-sectional area of the molybdenum-rhenium ingot and form a molybdenum-rhenium alloy containing said metal oxide. The present invention also provides an ODS molybdenum-rhenium alloy made by the method.
Date: December 1, 1998
Creator: Bianco, Robert & Buckman, William R. Jr.
System: The UNT Digital Library
Periodic equivalence ratio modulation method and apparatus for controlling combustion instability (open access)

Periodic equivalence ratio modulation method and apparatus for controlling combustion instability

The periodic equivalence ratio modulation (PERM) method and apparatus significantly reduces and/or eliminates unstable conditions within a combustion chamber. The method involves modulating the equivalence ratio for the combustion device, such that the combustion device periodically operates outside of an identified unstable oscillation region. The equivalence ratio is modulated between preselected reference points, according to the shape of the oscillation region and operating parameters of the system. Preferably, the equivalence ratio is modulated from a first stable condition to a second stable condition, and, alternatively, the equivalence ratio is modulated from a stable condition to an unstable condition. The method is further applicable to multi-nozzle combustor designs, whereby individual nozzles are alternately modulated from stable to unstable conditions. Periodic equivalence ratio modulation (PERM) is accomplished by active control involving periodic, low frequency fuel modulation, whereby low frequency fuel pulses are injected into the main fuel delivery. Importantly, the fuel pulses are injected at a rate so as not to affect the desired time-average equivalence ratio for the combustion device.
Date: December 1, 1998
Creator: Richards, George A.; Janus, Michael C. & Griffith, Richard A.
System: The UNT Digital Library
Process for strengthening aluminum based ceramics and material (open access)

Process for strengthening aluminum based ceramics and material

A process for strengthening aluminum based ceramics is provided. A gaseous atmosphere consisting essentially of silicon monoxide gas is formed by exposing a source of silicon to an atmosphere consisting essentially of hydrogen and a sufficient amount of water vapor. The aluminum based ceramic is exposed to the gaseous silicon monoxide atmosphere for a period of time and at a temperature sufficient to produce a continuous, stable silicon-containing film on the surface of the aluminum based ceramic that increases the strength of the ceramic.
Date: December 1, 1998
Creator: Moorhead, Arthur J. & Kim, Hyoun-Ee
System: The UNT Digital Library
Self-seeded injection-locked FEL amplifier (open access)

Self-seeded injection-locked FEL amplifier

A self-seeded free electron laser (FEL) provides a high gain and extraction efficiency for the emitted light. An accelerator outputs a beam of electron pulses to a permanent magnet wiggler having an input end for receiving the electron pulses and an output end for outputting light and the electron pulses. An optical feedback loop collects low power light in a small signal gain regime at the output end of said wiggler and returns the low power light to the input end of the wiggler while outputting high power light in a high signal gain regime.
Date: December 1, 1998
Creator: Sheffield, Richard L.
System: The UNT Digital Library
Solar reduction of CO{sub 2} (open access)

Solar reduction of CO{sub 2}

The red shift of the absorption spectrum of CO{sub 2} with increasing temperature, along with CO stabilization are the foundation of a process for direct solar reduction of CO{sub 2} to liquid fuels. The result is a process capable of using renewable solar energy to directly reduce CO{sub 2} from the atmosphere or stationary sources for recycle as a liquid fuel resulting in a net decrease in CO{sub 2} in the atmosphere and decreased demand on fossil fuel. The process includes in sequence: preparation of adequately pure CO{sub 2} feed; preheating CO{sub 2} to near 1,800 K; breaking the CO{sub 2} bonds to produce CO, O{sub 2} and O; quenching the hot product mix by rapid admixture with room temperature CO{sub 2}; removing excess thermal energy to produce electricity, heat new CO{sub 2} and enable subsequent process steps; removing the remaining CO{sub 2} from the gas; removing oxygen from the gas; converting part of the product CO to H{sub 2} by the shift reaction; and, finally, catalytically synthesizing methanol from the synthetic gas.
Date: December 1, 1998
Creator: Jensen, Reed J.; Lyman, John L.; King, Joe D. & Guettler, Robert D.
System: The UNT Digital Library
Thermionic converter with differentially heated cesium-oxygen source and method of operation (open access)

Thermionic converter with differentially heated cesium-oxygen source and method of operation

A thermionic converter having an emitter, a collector, and a source of cesium vapor is provided, wherein the source of cesium vapor is differentially heated so that said source has a hotter end and a cooler end, with cesium vapor evaporating from said hotter end into the space between the emitter and the collector and with cesium vapor condensing at said cooler end. The condensed cesium vapor migrates through a porous element from the cooler end to the hotter end.
Date: December 1, 1998
Creator: Rasor, N. S.; Riley, D. R.; Murray, C. S. & Geller, C. B.
System: The UNT Digital Library
A unique method of neutron flux determination from experimental data (open access)

A unique method of neutron flux determination from experimental data

A method is provided for determining the fission heat flux of a prime specimen inserted into a specimen of a test reactor. A pair of thermocouple test specimens are positioned at the same level in the holder and a determination is made of various experimental data including the temperature of the thermocouple test specimens, the temperature of bulk water channels located in the test holder, the gamma scan count ratios for the thermocouple test specimens and the prime specimen, and the thicknesses of the outer clads, the fuel fillers, and the backclad of the thermocouple test specimen. Using this experimental data, the absolute value of the fission heat flux for the thermocouple test specimens and prime specimen can be calculated.
Date: December 1, 1998
Creator: Paxton, Frank A.
System: The UNT Digital Library
Acoustic energy-driven fluid pump and method (open access)

Acoustic energy-driven fluid pump and method

Bulk fluid motion is promoted in a gaseous fluid contained within a conduit system provided with a diffuser without the need for a mean pressure differential across the conduit system. The contacting of the gaseous fluid with unsteady energy at a selected frequency and pressure amplitude induces fluid flow through the conical diffuser. The unsteady energy can be provided by pulse combustors, thermoacoustic engines, or acoustic energy generators such as acoustic speakers.
Date: December 1, 1997
Creator: Janus, Michael C.; Richards, George A. & Robey, Edward H.
System: The UNT Digital Library
An arc fault detection system (open access)

An arc fault detection system

An arc fault detection system for use on ungrounded or high-resistance-grounded power distribution systems is provided which can be retrofitted outside electrical switchboard circuits having limited space constraints. The system includes a differential current relay that senses a current differential between current flowing from secondary windings located in a current transformer coupled to a power supply side of a switchboard, and a total current induced in secondary windings coupled to a load side of the switchboard. When such a current differential is experienced, a current travels through a operating coil of the differential current relay, which in turn, opens an upstream circuit breaker located between the switchboard and a power supply to remove the supply of power to the switchboard.
Date: December 1, 1997
Creator: Jha, Kamal N.
System: The UNT Digital Library
Combined heat and mass transfer device for improving separation process (open access)

Combined heat and mass transfer device for improving separation process

A two-phase small channel heat exchange matrix for providing simultaneous heat transfer and mass transfer at a single, predetermined location within a separation column, whereby the thermodynamic efficiency of the separation process is significantly improved. The small channel heat exchange matrix is comprised of a series of channels having a hydraulic diameter no greater than 5.0 mm. The channels are connected to an inlet header for supplying a two-phase coolant to the channels and an outlet header for receiving the coolant horn the channels. In operation, the matrix provides the liquid-vapor contacting surfaces within a separation column, whereby liquid descends along the exterior surfaces of the cooling channels and vapor ascends between adjacent channels within the matrix. Preferably, a perforated and concave sheet connects each channel to an adjacent channel, such that liquid further descends along the concave surfaces of the sheets and the vapor further ascends through the perforations in the sheets. The size and configuration of the small channel heat exchange matrix allows the heat and mass transfer device to be positioned within the separation column, thereby allowing precise control of the local operating conditions within the column and increasing the energy efficiency of the process.
Date: December 1, 1997
Creator: Tran, Thanh Nhon
System: The UNT Digital Library
Constant field gradient planar cavity structure (open access)

Constant field gradient planar cavity structure

A cavity structure is described having at least two opposing planar housing members spaced apart to accommodate the passage of a particle beam through the structure between the members. Each of the housing members have a plurality of serially aligned hollows defined therein, and also passages, formed in the members, which interconnect serially adjacent hollows to provide communication between the hollows. The opposing planar housing members are spaced and aligned such that the hollows in one member cooperate with corresponding hollows in the other member to form a plurality of resonant cavities aligned along the particle beam within the cavity structure. To facilitate the obtaining of a constant field gradient within the cavity structure, the passages are configured so as to be incrementally narrower in the direction of travel of the particle beam. In addition, the spacing distance between the opposing housing members is configured to be incrementally smaller in the direction of travel of the beam.
Date: December 1, 1997
Creator: Kang, Yoon W. & Kustom, R.L.
System: The UNT Digital Library
Decontamination of matrices containing actinide oxides (open access)

Decontamination of matrices containing actinide oxides

There is provided a method for removing actinides and actinide oxides, particularly fired actinides, from soil and other contaminated matrices, comprising: (a) contacting a contaminated material with a solution of at least one inhibited fluoride and an acid to form a mixture; (b) heating the mixture of contaminated material and solution to a temperature in the range from about 30 C to about 90 C while stirring; (c) separating the solution from any undissolved matrix material in the mixture; (d) washing the undissolved matrix material to remove any residual materials; and (e) drying and returning the treated matrix material to the environment.
Date: December 1, 1997
Creator: Villarreal, Robert
System: The UNT Digital Library
Depleted uranium as a backfill for nuclear fuel waste package (open access)

Depleted uranium as a backfill for nuclear fuel waste package

A method is described for packaging spent nuclear fuel for long-term disposal in a geological repository. At least one spent nuclear fuel assembly is first placed in an unsealed waste package and a depleted uranium fill material is added to the waste package. The depleted uranium fill material comprises flowable particles having a size sufficient to substantially fill any voids in and around the assembly and contains isotonically-depleted uranium in the +4 valence state in an amount sufficient to inhibit dissolution of the spent nuclear fuel from the assembly into a surrounding medium and to lessen the potential for nuclear criticality inside the repository in the event of failure of the waste package. Last, the waste package is sealed, thereby substantially reducing the release of radionuclides into the surrounding medium, while simultaneously providing radiation shielding and increased structural integrity of the waste package.
Date: December 1, 1997
Creator: Forsberg, Charles W.
System: The UNT Digital Library
Direct detection of x-rays for protein crystallography (open access)

Direct detection of x-rays for protein crystallography

An apparatus and method for directly determining the crystalline structure of a protein crystal. The crystal is irradiated by a finely collimated x-ray beam. The interaction o f the x-ray beam with the crystal produces scattered x-rays. These scattered x-rays are detected by means of a large area, thick CCD which is capable of measuring a significant number of scattered x-rays which impact its surface. The CCD is capable of detecting the position of impact of the scattered x-ray on the surface of the CCD and the quantity of scattered x-rays which impact the same cell or pixel. This data is then processed in real-time and the processed data is outputted to produce an image of the structure of the crystal. If this crystal is a protein the molecular structure of the protein can be determined from the data received.
Date: December 1, 1997
Creator: Atac, Muzaffer & McKay, Timothy
System: The UNT Digital Library
Double opposite-end tubesheet design for a thermovoltaic energy converter (open access)

Double opposite-end tubesheet design for a thermovoltaic energy converter

A method and apparatus are disclosed for the direct conversion of energy by thermovoltaic energy conversion having first and second tubesheets, at least one photon emitter plate secured to and extending from the first tubesheet, at least one cold plate secured to and extending from the second tubesheet, a plurality of thermovoltaic cells disposed along oppositely disposed exterior surfaces of the cold plate, and means cooperating with the tubesheet for maintaining a vacuum between the photon emitter plate and the cold plate.
Date: December 1, 1997
Creator: Ashcroft, John M.; Campbell, Brain C. & DePoy, David M.
System: The UNT Digital Library
A filtered cathodic arc deposition apparatus and method (open access)

A filtered cathodic arc deposition apparatus and method

A filtered cathodic arc deposition method and apparatus are described for the production of highly dense, wear resistant coatings which are free from macro particles. The filtered cathodic arc deposition apparatus includes a cross shaped vacuum chamber which houses a cathode target having an evaporable surface comprised of the coating material, means for generating a stream of plasma, means for generating a transverse magnetic field, and a macro particle deflector. The transverse magnetic field bends the generated stream of plasma in the direction of a substrate. Macro particles are effectively filtered from the stream of plasma by traveling, unaffected by the transverse magnetic field, along the initial path of the plasma stream to a macro particle deflector. The macro particle deflector has a preformed surface which deflects macro particles away from the substrate.
Date: December 1, 1997
Creator: Krauss, Alan R.
System: The UNT Digital Library
Fuel element design for the enhanced destruction of plutonium in a nuclear reactor (open access)

Fuel element design for the enhanced destruction of plutonium in a nuclear reactor

A uranium-free fuel for a fast nuclear reactor comprising an alloy of Pu, Zr and Hf, wherein Hf is present in an amount less than about 10% by weight of the alloy. The fuel may be in the form of a Pu alloy surrounded by a Zr-Hf alloy or an alloy of Pu-Zr-Hf or a combination of both.
Date: December 1, 1997
Creator: Crawford, Douglas C.; Porter, Douglas L.; Hayes, Steven L. & Hill, Robert N.
System: The UNT Digital Library
High power X-ray welding of metal-matrix composites (open access)

High power X-ray welding of metal-matrix composites

A method for joining metal-matrix composites (MMCs) by using high power x-rays as a volumetric heat source is provided. The method involves directing an x-ray to the weld line between two adjacent MMCs materials to create an irradiated region or melt zone. The x-rays have a power density greater than about 10{sup 4} watts/cm{sup 2} and provide the volumetric heat required to join the MMC materials. Importantly, the reinforcing material of the metal-matrix composites remains uniformly distributed in the melt zone, and the strength of the MMCs are not diminished. In an alternate embodiment, high power x-rays are used to provide the volumetric heat required to weld metal elements, including metal elements comprised of metal alloys. In an alternate embodiment, high power x-rays are used to provide the volumetric heat required to weld metal elements, including metal elements comprised of metal alloys.
Date: December 1, 1997
Creator: Rosenberg, Richard A.; Goeppner, George A.; Noonan, John R.; Farrell, William J. & Ma, Qing
System: The UNT Digital Library
In-situ stabilization of radioactive zirconium swarf (open access)

In-situ stabilization of radioactive zirconium swarf

The method for treating ignitable cutting swarf in accordance with the present invention involves collecting cutting swarf in a casting mold underwater and injecting a binder mixture comprising vinyl ester styrene into the vessel to fill void volume; and form a mixture comprising swarf and vinyl ester styrene; and curing the mixture. The method is especially useful for stabilizing the ignitable characteristics of radioactive zirconium cutting swarf, and can be used to solidify zirconium swarf, or other ignitable finely divided material, underwater. The process could also be performed out of water with other particulate wastes.
Date: December 1, 1997
Creator: Hess, Clay C.
System: The UNT Digital Library
Inherently safe helium-3 target canister for tritium production in fission systems (open access)

Inherently safe helium-3 target canister for tritium production in fission systems

A method and apparatus are described for creating tritium via the irradiation of {sup 3}He with thermal neutrons via the {sup 3}He(n,p)T reaction. Nuclear reactors can provide the required neutrons, but the safety of putting {sup 3}He in a reactor has been an issue. The invention reduces or eliminates the reactivity insertion which would be occasioned by a loss of {sup 3}He by providing a canister constructed partially of high neutron-absorbing materials, which will continue to absorb thermal neutrons whether or not the {sup 3}He is still contained within the canister. The canister thus makes the use of the {sup 3}He(n,p)T reaction a viable, safe option for producing tritium within nuclear reactors. In reactors dominated by fast neutrons, the canister further includes a moderator to thermalize fast neutrons.
Date: December 1, 1997
Creator: Houts, Michael G. & James, Brian J.
System: The UNT Digital Library
A method and apparatus for destroying hazardous organics and other combustible materials in a subcritical/supercritical reactor (open access)

A method and apparatus for destroying hazardous organics and other combustible materials in a subcritical/supercritical reactor

A waste destruction method is described using a reactor vessel to combust and destroy organic and combustible waste, including the steps of introducing a supply of waste into the reactor vessel, introducing a supply of an oxidant into the reactor vessel to mix with the waste forming a waste and oxidant mixture, introducing a supply of water into the reactor vessel to mix with the waste and oxidant mixture forming a waste, water and oxidant mixture, reciprocatingly compressing the waste, water and oxidant mixture forming a compressed mixture, igniting the compressed mixture forming a exhaust gas, and venting the exhaust gas into the surrounding atmosphere.
Date: December 1, 1997
Creator: Janikowski, Stuart K.
System: The UNT Digital Library