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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
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
A thermovoltaic semiconductor device including a plasma filter (open access)

A thermovoltaic semiconductor device including a plasma filter

A thermovoltaic energy conversion device and related method for converting thermal energy into an electrical potential are disclosed. An interference filter is provided on a semiconductor thermovoltaic cell to pre-filter black body radiation. The semiconductor thermovoltaic cell includes a P/N junction supported on a substrate which converts incident thermal energy below the semiconductor junction band gap into electrical potential. The semiconductor substrate is doped to provide a plasma filter which reflects back energy having a wavelength which is above the band gap and which is ineffectively filtered by the interference filter, through the P/N junction to the source of radiation thereby avoiding parasitic absorption of the unusable portion of the thermal radiation energy.
Date: December 1, 1997
Creator: Baldasaro, Paul F.
System: The UNT Digital Library
Nonrotating, self-centering anchor assembly for anchoring a bolt in a borehole (open access)

Nonrotating, self-centering anchor assembly for anchoring a bolt in a borehole

An expandable anchor assembly is provided for anchoring the threaded end portion of an elongated roof bolt in a borehole. The anchoring assembly includes a hollow outer sleeve in the form of a plurality of symmetrically arranged, longitudinal segmented wall portions with exterior gripping teeth and an inner expander sleeve in the form of a corresponding plurality of longitudinal wall portions symmetrically arranged about a central axis to define an inner threaded cylindrical section. The inner sleeve is captured within and moveable axially relative to the outer sleeve. As the threaded end portion of the elongated bolt is inserted into the inner threaded cylindrical section of the inner sleeve from the trailing end to the leading end thereof, the inner sleeve expands over and clamps around the threaded end portion of the elongated bolt. Thereafter, partial withdrawal of the elongated bolt from the borehole causes the inner sleeve to axially move relative to the outer sleeve from the leading end toward the trailing end of the outer sleeve in a wedging action to cause the outer sleeve to radially expand and force engagement of the gripping teeth against the sidewall of the borehole to thereby secure the expandable anchor assembly …
Date: December 1, 1997
Creator: Bevan, John E. & King, Grant W.
System: The UNT Digital Library
High-strength, creep-resistant molybdenum alloy and process for producing the same (open access)

High-strength, creep-resistant molybdenum alloy and process for producing the same

A wet-doping process for producing an oxide-dispersion strengthened (ODS), creep-resistant molybdenum alloy is disclosed. The alloy is made by adding nitrate or acetate salts of lanthanum, cerium, thorium, or yttrium to molybdenum oxide to produce a slurry, heating the slurry in a hydrogen atmosphere to produce a powder, mixing and cold isostatically pressing the powder, sintering in a hydrogen atmosphere, and thermomechanically processing (swaging, extruding, cold drawing) the product. The ODS molybdenum alloy produced by the process contains 2--4% by volume ({approximately}1--4% by weight) of an oxide of lanthanum, cerium, thorium, or yttrium. The alloy has high strength and improved creep-resistance at temperatures greater than 0.55T{sub m} of molybdenum.
Date: 1997~
Creator: Bianco, Robert; Buckman, William R., Jr. & Geller, Clint B.
System: The UNT Digital Library
Method for producing low-cost, high volume hydrogen from hydrocarbon sources (open access)

Method for producing low-cost, high volume hydrogen from hydrocarbon sources

A method is described for the conversion of naturally-occurring or biomass-derived lower to higher hydrocarbon (C{sub x}H{sub y},where x may vary from 1--3 and y may vary from 4--8) to low-cost, high-volume hydrogen. In one embodiment, methane, the major component of natural gas, is reacted in a single reaction zone of a mixed-conducting ceramic membrane reactor to form hydrogen via simultaneous partial oxidation and water gas shift reactions at temperatures required for thermal excitations of the mixed-conducting membranes. The hydrogen is produced by catalytically reacting the hydrocarbon with oxygen to form synthesis gas (a mixture of carbon monoxide and hydrogen), followed by a water gas shift (WGS) reaction with steam, wherein both reactions occur in a single reaction zone having a multi-functional catalyst or a combination of catalysts. The hydrogen is separated from other reaction products by membrane-assisted transport or by pressure-swing adsorption technique. Membrane-assisted transport may occur via proton transfer or molecular sieving mechanisms.
Date: December 1, 1997
Creator: Bose, Arun C.; Balachandran, Uthamalinga; Kleerfisch, Mark S.; Udovich, Carl A. & Stiegel, Gary J.
System: The UNT Digital Library
A method for separating water soluble organics from a process stream by aqueous biphasic extraction (open access)

A method for separating water soluble organics from a process stream by aqueous biphasic extraction

The present invention relates to a method for separating water-miscible organic species from a process stream by aqueous biphasic extraction. In particular, the method includes extracting the organic species into a polymer-rich phase of an aqueous biphase system in which the process stream comprises the salt-rich phase, and, next, separating the polymer from the extracted organic species by contacting the loaded, polymer-rich phase with a water-immiscible organic phase. Alternatively, the polymer can be separated from the extracted organic species by raising the temperature of the loaded, polymer-rich phase above the cloud point, such that the polymer and the water-soluble organic species separate into two distinct aqueous phases. In either case, a substantially salt-free, concentrated aqueous solution containing the organic species is recovered.
Date: December 1, 1997
Creator: Chaiko, David J. & Mego, William A.
System: The UNT Digital Library
Strain gauge installation tool (open access)

Strain gauge installation tool

A tool and a method for attaching a strain gauge to a test specimen by maintaining alignment of, and applying pressure to, the strain gauge during the bonding of the gauge to the specimen. The tool comprises rigid and compliant pads attached to a spring-loaded clamp. The pads are shaped to conform to the specimen surface to which the gauge is to be bonded. The shape of the pads permits the tool to align itself to the specimen and to maintain alignment of the gauge to the specimen during the bond curing process. A simplified method of attaching a strain gauge is provided by use of the tool.
Date: December 1, 1997
Creator: Conard, Lisa Marie
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
Performance evaluation soil samples utilizing encapsulation technology (open access)

Performance evaluation soil samples utilizing encapsulation technology

Performance evaluation soil samples and method of their preparation are described using encapsulation technology to encapsulate analytes which are introduced into a soil matrix for analysis and evaluation by analytical laboratories. Target analytes are mixed in an appropriate solvent at predetermined concentrations. The mixture is emulsified in a solution of polymeric film forming material. The emulsified solution is polymerized to form microcapsules. The microcapsules are recovered, quantitated and introduced into a soil matrix in a predetermined ratio to form soil samples with the desired analyte concentration.
Date: December 1, 1997
Creator: Dahlgran, James R.
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
Recovery of fissile materials from nuclear wastes (open access)

Recovery of fissile materials from nuclear wastes

A process is described for recovering fissile materials such as uranium, and plutonium, and rare earth elements, from complex waste feed material, and converting the remaining wastes into a waste glass suitable for storage or disposal. The waste feed is mixed with a dissolution glass formed of lead oxide and boron oxide resulting in oxidation, dehalogenation, and dissolution of metal oxides. Carbon is added to remove lead oxide, and a boron oxide fusion melt is produced. The fusion melt is essentially devoid of organic materials and halogens, and is easily and rapidly dissolved in nitric acid. After dissolution, uranium, plutonium, and rare earth elements are separated from the acid and recovered by processes such as PUREX or ion exchange. The remaining acid waste stream is vitrified to produce a waste glass suitable for storage or disposal. Potential waste feed materials include plutonium scrap and residue, miscellaneous spent nuclear fuel, and uranium fissile wastes. The initial feed materials may contain mixtures of metals, ceramics, amorphous solids, halides, organic material and other carbon-containing material.
Date: December 1, 1997
Creator: Forsberg, Charles W.
System: The UNT Digital Library
VO{sub 2} precipitates for self-protected optical surfaces (open access)

VO{sub 2} precipitates for self-protected optical surfaces

A method for forming crystallographically coherent precipitates of vanadium dioxide in the near-surface region of sapphire and the resulting product is disclosed. Ions of vanadium and oxygen are stoichiometrically implanted into a sapphire substrate (Al{sub 2}O{sub 3}), and subsequently annealed to form vanadium dioxide precipitates in the substrate. The embedded VO{sub 2} precipitates, which are three-dimensionally oriented with respect to the crystal axes of the Al{sub 2}O{sub 3} host lattice, undergo a first-order monoclinic-to-tetragonal (and also semiconducting-to- metallic) phase transition at {minus}77 C. This transformation is accompanied by a significant variation in the optical transmission of the implanted region and results in the formation of an optically active, thermally switchable surface region on Al{sub 2}O{sub 3}.
Date: December 1, 1997
Creator: Gea, Laurence A. & Boatner, Lynn A.
System: The UNT Digital Library
Multi-stage fuel cell system method and apparatus (open access)

Multi-stage fuel cell system method and apparatus

A high efficiency, multi-stage fuel cell system method and apparatus is provided. The fuel cell system is comprised of multiple fuel cell stages, whereby the temperatures of the fuel and oxidant gas streams and the percentage of fuel consumed in each stage are controlled to optimize fuel cell system efficiency. The stages are connected in a serial, flow-through arrangement such that the oxidant gas and fuel gas flowing through an upstream stage is conducted directly into the next adjacent downstream stage. The fuel cell stages are further arranged such that unspent fuel and oxidant laden gases too hot to continue within an upstream stage because of material constraints are conducted into a subsequent downstream stage which comprises a similar cell configuration, however, which is constructed from materials having a higher heat tolerance and designed to meet higher thermal demands. In addition, fuel is underutilized in each stage, resulting in a higher overall fuel cell system efficiency.
Date: December 1, 1997
Creator: George, Thomas J. & Smith, William C.
System: The UNT Digital Library
One-way implodable tag capsule with hemispherical beaded end cap for LWR fuel manufacturing (open access)

One-way implodable tag capsule with hemispherical beaded end cap for LWR fuel manufacturing

A capsule is described containing a tag gas in a zircaloy body portion having a hemispherical top curved toward the bottom of the body portion. The hemispherical top has a rupturable portion upon exposure to elevated gas pressure and the capsule is positioned within a fuel element in a nuclear reactor.
Date: December 1, 1997
Creator: Gross, Kenny & Lambert, John
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
Nuclear fuel elements made from nanophase materials (open access)

Nuclear fuel elements made from nanophase materials

A nuclear reactor core fuel element is composed of nanophase high temperature materials. An array of the fuel elements in rod form are joined in an open geometry fuel cell that preferably also uses such nanophase materials for the cell structures. The particular high temperature nanophase fuel element material must have the appropriate mechanical characteristics to avoid strain-related failure even at high temperatures, in the order of about 3,000 F. Preferably, the reactor type is a pressurized or boiling water reactor and the nanophase material is a high temperature ceramic or ceramic composite. Nanophase metals, or nanophase metals with nanophase ceramics in a composite mixture, also have desirable characteristics, although their temperature capability is not as great as with all ceramic nanophase material. Combinations of conventional or nanophase metals and conventional or nanophase ceramics can be employed as long as there is at least one nanophase material in the composite. The nuclear reactor so constructed has a number of high strength fuel particles, a nanophase structural material for supporting a fuel rod at high temperature, a configuration to allow passive cooling in the event of a primary cooling system failure, an ability to retain a coolable geometry even at high …
Date: December 1, 1997
Creator: Heubeck, Norman B.
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
System for improving electrostatic precipitator performance by plasma reactor conversion of SO{sub 2} to SO{sub 3} (open access)

System for improving electrostatic precipitator performance by plasma reactor conversion of SO{sub 2} to SO{sub 3}

None
Date: December 1, 1997
Creator: Huang, H.S. & Gorski, A.J.
System: The UNT Digital Library
Method for removing heavy metal and nitrogen oxides from flue gas, device for removing heavy metal and nitrogen oxides from flue gas (open access)

Method for removing heavy metal and nitrogen oxides from flue gas, device for removing heavy metal and nitrogen oxides from flue gas

A method for the simultaneous removal of oxides and heavy metals from a fluid is provided comprising combining the fluid with compounds containing alkali and sulfur to create a mixture; spray drying the mixture to create a vapor phase and a solid phase; and isolating the vapor phase from the solid phase. A device is also provided comprising a means for spray-drying flue gas with alkali-sulfide containing liquor at a temperature sufficient to cause the flue gas to react with the compounds so as to create a gaseous fraction and a solid fraction and a means for directing the gaseous fraction to a fabric filter.
Date: December 1, 1997
Creator: Huang, Hann-Sheng & Livengood, Charles David
System: The UNT Digital Library
TRIAC/SCR proportional control circuit (open access)

TRIAC/SCR proportional control circuit

A power controller device which uses a voltage-to-frequency converter in conjunction with a zero crossing detector to linearly and proportionally control AC power being supplied to a load. The output of the voltage to frequency converter controls the reset input of a R-S flip flop, while an 0 crossing detector controls the set input. The output of the flip flop triggers a monostable multivibrator controlling the SCR or TRIAC firing circuit connected to the load. Logic gates prevent the direct triggering of the multivibrator in the rare instance where the reset and set inputs of the flip flop are in coincidence. The control circuit can be supplemented with a control loop, providing compensation for line voltage variations.
Date: December 1, 1997
Creator: Hughes, Wallace 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
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
A sampling device with a capped body and detachable handle (open access)

A sampling device with a capped body and detachable handle

The present invention relates to a device for sampling radioactive waste and more particularly to a device for sampling radioactive waste which prevents contamination of a sampled material and the environment surrounding the sampled material. During vitrification of nuclear wastes, it is necessary to remove contamination from the surfaces of canisters filled with radioactive glass. After removal of contamination, a sampling device is used to test the surface of the canister. The one piece sampling device currently in use creates a potential for spreading contamination during vitrification operations. During operations, the one piece sampling device is transferred into and out of the vitrification cell through a transfer drawer. Inside the cell, a remote control device handles the sampling device to wipe the surface of the canister. A one piece sampling device can be contaminated by the remote control device prior to use. Further, the sample device can also contaminate the transfer drawer producing false readings for radioactive material. The present invention overcomes this problem by enclosing the sampling pad in a cap. The removable handle is reused which reduces the amount of waste material.
Date: December 1, 1997
Creator: Jezek, Gerd-Rainer
System: The UNT Digital Library