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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
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
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
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
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
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
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
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}
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
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
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
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
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
Assembly and method for testing the integrity of stuffing tubes
A stuffing tube integrity checking assembly includes first and second annular seals, with each seal adapted to be positioned about a stuffing tube penetration component. An annular inflation bladder is provided, the bladder having a slot extending longitudinally there along and including a separator for sealing the slot. A first valve is in fluid communication with the bladder for introducing pressurized fluid to the space defined by the bladder when mounted about the tube. First and second releasible clamps are provided. Each clamp assembly is positioned about the bladder for securing the bladder to one of the seals for thereby establishing a fluid-tight chamber about the tube.
Date:
December 31, 1996
Creator:
Morrison, Edward F.
System:
The UNT Digital Library
Bulk single crystal ternary substrates for a thermophotovoltaic energy conversion system
A thermophotovoltaic energy conversion device and a method for making the device are disclosed. The device includes a substrate formed from a bulk single crystal material having a bandgap (E{sub g}) of 0.4 eV < E{sub g} < 0.7 eV and an emitter fabricated on the substrate formed from one of a p-type and an n-type material. Another thermophotovoltaic energy conversion device includes a host substrate formed from a bulk single crystal material and lattice-matched ternary or quaternary III-V semiconductor active layers.
Date:
December 31, 1996
Creator:
Charache, Greg W.; Baldasaro, Paul F. & Nichols, Greg J.
System:
The UNT Digital Library
Cable load sensing device
Apparatus for sensing the magnitude of a load on a cable as the cable is employed to support the load includes a beam structure clamped to the cable so that a length of the cable lies along the beam structure. A spacer associated with the beam structure forces a slight curvature in a portion of the length of cable under a cable no-load condition so that the portion of the length of cable is spaced from the beam structure to define a cable curved portion. A strain gauge circuit including strain gauges is secured to the beam structure by welding. As the cable is employed to support a load the load causes the cable curved portion to exert a force normal to the cable through the spacer and on the beam structure to deform the beam structure as the cable curved portion attempts to straighten under the load. As this deformation takes place, the resistance of the strain gauges is set to a value proportional to the magnitude of the normal strain on the beam structure during such deformation. The magnitude of the normal strain is manipulated in a control device to generate a value equal to the magnitude or …
Date:
December 31, 1996
Creator:
Beus, M. J. & McCoy, W. G.
System:
The UNT Digital Library
Combustor oscillation pressure stabilizer
In accordance with the objective of the present invention, the active control of unsteady combustion induced oscillations in a combustion chamber fired by a suitable fuel and oxidizer mixture, such as a hydrocarbon fuel and air mixture, is provided by restructuring and moving the position of the main flame front and thereby increasing the transport time and displacing the pressure wave further away from the in-phase relationship with the periodic heat release. The restructuring and repositioning of the main flame are achieved by utilizing a pilot flame which is pulsed at a predetermined frequency corresponding to less than about one-half the frequency of the combustion oscillation frequency with the duration of each pulse being sufficient to produce adequate secondary thermal energy to restructure the main flame and thereby decouple the heat release from the acoustic coupling so as to lead to a reduction in the dynamic pressure amplitude. The pulsating pilot flame produces a relatively small and intermittently existing flame front in the combustion zone that is separate from the oscillating main flame front but which provides the thermal energy necessary to effectively reposition the location of the oscillating main flame front out of the region in the combustion zone …
Date:
December 31, 1996
Creator:
Gemmen, R. S.; Richards, G. A.; Yip, M. T. J.; Robey, E.; Cully, S. R. & Addis, R. E.
System:
The UNT Digital Library
Compact cyclone filter train for radiological and hazardous environments
A compact cyclone filter train is described for the removal of hazardous and radiological particles from a gaseous fluid medium which permits a small cyclone separator to be used in a very small space envelope due to the arrangement of the filter housing adjacent to the separator with the cyclone separators and the filters mounted on a plate. The entire unit will have a hoist connection at the center of gravity so that the entire unit including the separator, the filters, and the base can be lifted and repositioned as desired.
Date:
December 31, 1996
Creator:
Bench, T. R.
System:
The UNT Digital Library
Down-flow moving-bed gasifier with catalyst recycle
The gasification of coal and other carbonaceous materials by an endothermic gasification reaction is achieved in the presence of a catalyst in a down-flow, moving-bed gasifier. Catalyst is removed along with ash from the gasifier and is then sufficiently heated in a riser/burner by the combustion of residual carbon in the ash to volatilize the catalyst. This volatilized catalyst is returned to the gasifier where it uniformly contacts and condenses on the carbonaceous material. Also, the hot gaseous combustion products resulting from the combustion of the carbon in the ash along with excess air are introduced into the gasifier for providing heat energy used in the endothermic reaction.
Date:
December 31, 1996
Creator:
Halow, John S.
System:
The UNT Digital Library
Graphitic packing removal tool
Graphitic packing removal tools are described for removal of the seal rings in one piece from valves and pumps. The packing removal tool has a cylindrical base ring the same size as the packing ring with a surface finish, perforations, knurling or threads for adhesion to the seal ring. Elongated leg shanks are mounted axially along the circumferential center. A slit or slits permit insertion around shafts. A removal tool follower stabilizes the upper portion of the legs to allow a spanner wrench to be used for insertion and removal.
Date:
December 31, 1996
Creator:
Meyers, K.E. & Kolsun, G.J.
System:
The UNT Digital Library
Holding fixture for metallographic mount polishing
A fixture for holding mounted specimens for polishing, having an arm; a body attached to one end of the arm, the body having at least one flange having an opening to accommodate a mounted specimen; and a means applying pressure against the outer surface of the mounted specimen to hold the specimen in contact with the polishing surface.
Date:
December 31, 1996
Creator:
Barth, C.H. & Cramer, C.E.
System:
The UNT Digital Library
Hybrid high direct current circuit interrupter
A device and a method for interrupting very high direct currents (greater than 100,000 amperes) and simultaneously blocking high voltages (greater than 600 volts). The device utilizes a mechanical switch to carry very high currents continuously with low loss and a silicon controlled rectifier (SCR) to bypass the current around the mechanical switch while its contacts are separating. A commutation circuit, connected in parallel with the SCR, turns off the SCR by utilizing a resonant circuit to divert the SCR current after the switch opens.
Date:
December 31, 1996
Creator:
Rockot, Joseph H.; Mikesell, Harvey E. & Jha, Kamal N.
System:
The UNT Digital Library
Improved method for the production of atomic ion species from plasma ion sources
A technique to enhance the yield of neutral atomic and ionic species (H{sup +}, D{sup +}, O{sup +}, N{sup +}, etc.) from plasmas. The technique involves the addition of catalyzing agents to the ion discharge. Effective catalysts include H{sub 2}O, O{sub 2}, and SF{sub 6}, among others, with the most effective being water (H{sub 2}O). This technique has been developed at Argonne National Laboratory, where microwave produced beams consisting essentially of 100% atomic neutral species (H) have been generated, and ion beams of close to 100% purity have been generated.
Date:
December 31, 1996
Creator:
Spence, D. & Lykke, K.
System:
The UNT Digital Library
Lapped substrate for enhanced backsurface reflectivity in a thermophotovoltaic energy conversion system
A method is described for fabricating a thermophotovoltaic energy conversion cell including a thin semiconductor wafer substrate having a thickness ({beta}) calculated to decrease the free carrier absorption on a heavily doped substrate; wherein the top surface of the semiconductor wafer substrate is provided with a thermophotovoltaic device, a metallized grid and optionally an antireflective (AR) overcoating; and, the bottom surface (10 ft) of the semiconductor wafer substrate is provided with a highly reflecting coating which may comprise a metal coating or a combined dielectric/metal coating.
Date:
December 31, 1996
Creator:
Baldasaro, Paul F.; Brown, Edward J.; Charache, Greg W. & DePoy, David M.
System:
The UNT Digital Library