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A method for the removal of elemental mercury from a gas stream (open access)

A method for the removal of elemental mercury from a gas stream

A method is provided to remove elemental mercury from a gas stream by reacting the gas stream with an oxidizing solution to convert the elemental mercury to soluble mercury compounds. Other constituents are also oxidized. The gas stream is then passed through a wet scrubber to remove the mercuric compounds and oxidized constituents.
Date: December 1, 1997
Creator: Mendelsohn, Marshall H. & Huang, Hann-Sheng
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
Near real time vapor detection and enhancement using aerosol adsorption (open access)

Near real time vapor detection and enhancement using aerosol adsorption

A vapor sample detection method where the vapor sample contains vapor and ambient air and surrounding natural background particles. The vapor sample detection method includes the steps of generating a supply of aerosol that have a particular effective median particle size, mixing the aerosol with the vapor sample forming aerosol and adsorbed vapor suspended in an air stream, impacting the suspended aerosol and adsorbed vapor upon a reflecting element, alternatively directing infrared light to the impacted aerosol and adsorbed vapor, detecting and analyzing the alternatively directed infrared light in essentially real time using a spectrometer and a microcomputer and identifying the vapor sample.
Date: December 1, 1997
Creator: Novick, Vincent J. & Johnson, Stanley A.
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
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
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
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
Process and material that encapsulates solid hazardous waste (open access)

Process and material that encapsulates solid hazardous waste

A method is described for encapsulating mixed waste in which a thermoplastic polymer having a melting temperature less than about 150 C and sulfur and mixed waste are mixed at an elevated temperature not greater than about 200 C and mixed for a time sufficient to intimately mix the constituents, and then cooled to a solid. The resulting solid is also disclosed.
Date: December 1, 1997
Creator: O'Brien, Michael H. & Erickson, Arnold W.
System: The UNT Digital Library
Process for removing technetium from iron and other metals (open access)

Process for removing technetium from iron and other metals

Technetium is a radioactive product of the nuclear fission process. During reprocessing of spent or partially spent fuel from nuclear reactors, the technetium can be released and contaminate other, otherwise good, metals. A specific example is equipment in gaseous diffusion uranium enrichment cascades which have been used to process fuel which was returned from reactors, so-called reactor returns. These returns contained volatile technetium compounds which contaminated the metals in the equipment. Present regulations require that technetium be removed before the metal can be re-used at non-radioactive sites. Removing the technetium from contaminated metals has two desirable results. First, the large amount of nonradioactive metal produced by the process herein described can be recycled at a much lower cost than virgin metal can be produced. Second, large amounts of radioactively contaminated metal can be reduced to relatively small amounts of radioactive slag and large amounts of essentially uncontaminated metal. A new and improved process for removing technetium from iron and other metals is described in which between 1/10 atom % and 5 atom % of manganese is added to the contaminated metal in order to replace the technetium.
Date: December 1, 1997
Creator: Leitnaker, James M. & Trowbridge, Lee D.
System: The UNT Digital Library
Process management using component thermal-hydraulic function classes (open access)

Process management using component thermal-hydraulic function classes

A process management expert system for a nuclear, chemical or other process is effective following malfunctioning of a component, such as a pump, for determining system realignment procedures such as for by-passing the malfunctioning component with on-line speeds to maintain operation of the process at full or partial capacity or to provide safe shut down of the system while isolating the malfunctioning component. The expert system uses thermal-hydraulic function classes at the component level for analyzing unanticipated as well as anticipated component malfunctions to provide recommended sequences of operator actions. Each component is classified according to its thermal-hydraulic function, and the generic and component-specific characteristics for that function. Using the diagnosis of the malfunctioning component and its thermal hydraulic class, the expert system analysis is carried out using generic thermal-hydraulic first principles. One aspect of the invention employs a qualitative physics-based forward search directed primarily downstream from the malfunctioning component in combination with a subsequent backward search directed primarily upstream from the serviced component. Generic classes of components are defined in the knowledge base according to the three thermal-hydraulic functions of mass, momentum and energy transfer and are used to determine possible realignment of component configurations in response to thermal-hydraulic …
Date: December 1, 1997
Creator: Morman, James A.; Wei, Thomas Y.C. & Reifman, Jaques
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
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
Solid oxide fuel cell with multi-unit construction and prismatic design (open access)

Solid oxide fuel cell with multi-unit construction and prismatic design

A single cell unit of a solid oxide fuel cell is described that is individually fabricated and sintered prior to being connected to adjacent cells to form a solid oxide fuel cell . The single cell unit is comprised of a shaped anode sheet positioned between a flat anode sheet and an anode-electrolyte-cathode (A/E/C) sheet, and a shaped cathode sheet positioned between the A/E/C sheet and a cathode-interconnect-anode (C/I/A) sheet. An alternate embodiment comprises a shaped cathode sheet positioned between an A/E/C sheet and a C/I/A sheet. The shaped sheets form channels for conducting reactant gases. Each single cell unit is individually sintered to form a finished sub-assembly. The finished sub-assemblies are connected in electrical series by interposing connective material between the end surfaces of adjacent cells, whereby individual cells may be inspected for defects and interchanged with non-defective single cell units.
Date: December 1, 1997
Creator: McPheeters, Charles C.; Dees, Dennis W. & Myles, Kevin M.
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
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
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
Time-of-flight SIMS/MSRI reflectron mass analyzer and method (open access)

Time-of-flight SIMS/MSRI reflectron mass analyzer and method

A method and apparatus for analyzing the surface characteristics of a sample by Secondary Ion Mass Spectroscopy (SIMS) and Mass Spectroscopy of Recoiled Ions (MSFU) is provided. The method includes detecting back scattered primary ions, low energy ejected species, and high energy ejected species by ion beam surface analysis techniques comprising positioning a ToF SIMS/MSRI mass analyzer at a predetermined angle {theta}, where {theta} is the angle between the horizontal axis of the mass analyzer and the unreflected primary ion beam line, and applying a specific voltage to the back ring of the analyzer. Preferably, {theta} is less than or equal to about 120{degree} and, more preferably, equal to 74{degree}. For positive ion analysis, the extractor, lens, and tint ring of the reflection are set at negative high voltages ({minus}Hv). The back ring of the reflection is set at greater than about +700V for MSRI measurements and between the range of about +15V and about +50V for SIMS measurements. The method further comprises inverting the polarity of the potentials applied to the extractor, lens, front ring, and back ring to obtain negative ion SIMS and/or MSRI data.
Date: December 1, 1997
Creator: Smentkowski, Vincent S.; Gruen, Dieter M.; Krauss, Alan R.; Schultz, Albert J. & Holecek, John C.
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
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