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Microwave sintering of multiple aritcles
Disclosed are apparatus and method for producing articles of alumina and of alumina and silicon carbide in which the articles are sintered at high temperatures using microwave radiation. The articles are placed in a sintering container which is placed in a microwave cavity for heating. The rates at which heating and cooling take place is controlled.
Date:
December 31, 1992
Creator:
Blake, R. D. & Katz, J. D.
System:
The UNT Digital Library
Ceramic tamper-revealing seals
A tamper resistant seal is made of a brittle material with internal defects internally arranged in a random pattern to form a unique fingerprint characteristic of the seal which may be identified by ultrasonic scanning to determine whether tampering has occurred. It comprises a flexible metal or ceramic cable with composite ceramic ends or a U-shaped ceramic connecting element attached to a binding element plate or block cast from alumina or Zr, and connected to the connecting element by shrink fitting. Part of the binding element is cast with NiO{sub 2} particles, which allows ultrasonic scanning and the resulting fingerprint. 7 figs.
Date:
December 31, 1991
Creator:
Kupperman, D. S.; Raptis, A. C. & Sheen, Shuh-Haw
System:
The UNT Digital Library
Compact self-contained electrical-to-optical converter/transmitter
An electrical-to-optical converter/transmitter is disclosed. A first optical receiver and a second optical receiver are provided for receiving a calibrate command and a power switching signal, respectively, from a remote processor. A third receiver is provided for receiving an analog electrical signal from a transducer. A calibrator generates a reference signal in response to the calibrate command. A combiner mixes the electrical signal with the reference signal to form a calibrated signal. A converter converts the calibrated signal to an optical signal. A transmitter transmits the optical signal to the remote processor. A primary battery supplies power to the calibrator, the combiner, the converter, and the transmitter. An optically-activated switch supplies power to the calibrator, the combiner, the converter, and the transmitter in response to the power switching signal. An auxiliary battery supplies power continuously to the switch means.
Date:
December 31, 1992
Creator:
Seligmann, D. A.; Moss, W. C.; Valk, T. C. & Conder, A. D.
System:
The UNT Digital Library
Passive decay heat removal system for water-cooled nuclear reactors
This document describes passive decay-heat removal system for a water-cooled nuclear reactor which employs a closed heat transfer loop having heat-exchanging coils inside an open-topped, insulated evaporator located inside the reactor vessel, below its normal water level, in communication with a condenser located outside of containment and exposed to the atmosphere. The heat transfer loop is located such that the evaporator is in a position where, when the water level drops in the reactor, it will become exposed to steam. Vapor produced in the evaporator passes upward to the condenser above the normal water level. In operation, condensation in the condenser removes heat from the system, and the condensed liquid is returned to the evaporator. The system is disposed such that during normal reactor operations where the water level is at its usual position, very little heat will be removed from the system, but during emergency, low water level conditions, substantial amounts of decay heat will be removed.
Date:
December 31, 1990
Creator:
Forseberg, C. W.
System:
The UNT Digital Library
Tritium monitor
This invention is comprised of a system for continuously monitoring the concentration of tritium in an aqueous stream. The system pumps a sample of the stream to magnesium-filled combustion tube which reduces the sample to extract hydrogen gas. The hydrogen gas is then sent to an isotope separation device where it is separated into two groups of isotopes: a first group of isotopes containing concentrations of deuterium and tritium, and a second group of isotopes having substantially no deuterium and tritium. The first group of isotopes containing concentrations of deuterium and tritium is then passed through a tritium detector that produces an output proportional to the concentration of tritium detected. Preferably, the detection system also includes the necessary automation and data collection equipment and instrumentation for continuously monitoring an aqueous stream.
Date:
December 31, 1992
Creator:
Chastagner, P.
System:
The UNT Digital Library
Open apex shaped charge-type explosive device having special disc means with slide surface thereon to influence movement of open apex shaped charge liner during collapse of same during detonation
An open apex shape charge explosive device is disclosed having an inner liner defining a truncated cone, an explosive charge surrounding the truncated inner liner, a primer charge, and a disc located between the inner liner and the primer charge for directing the detonation of the primer charge around the end edge of the disc means to the explosive materials surrounding the inner liner. The disc comprises a material having one or more of: a higher compressive strength, a higher hardness, and/or a higher density than the material comprising the inner liner, thereby enabling the disc to resist deformation until the liner collapses. The disc has a slide surface thereon on which the end edge of the inner liner slides inwardly toward the vertical axis of the device during detonation of the main explosive surrounding the inner liner, to thereby facilitate the inward collapse of the inner liner. In a preferred embodiment, the geometry of the slide surface is adjusted to further control the collapse or {beta} angle of the inner liner.
Date:
December 31, 1992
Creator:
Murphy, M. J.
System:
The UNT Digital Library
Laser patterning of laminated structures for electroplating
Disclosed is a process for laser patterning of a substrate so that it can be subsequently electroplated or electrolessly plated. The process utilizes a laser to treat an inactive (inert) layer formed over an active layer to either combine or remove the inactive layer to produce a patterned active layer on which electrodeposition can occur. The process is carried out by utilizing laser alloying and laser etching, and involves only a few relatively high yield steps and can be performed on a very small scale.
Date:
December 31, 1992
Creator:
Mayer, S. T. & Evans, L. B.
System:
The UNT Digital Library
High resolution data acquisition
A high resolution event interval timing system measures short time intervals such as occur in high energy physics or laser ranging. Timing is provided from a clock pulse train and analog circuitry for generating a triangular wave synchronously with the pulse train. The triangular wave has an amplitude and slope functionally related to the time elapsed during each clock pulse in the train. A converter forms a first digital value of the amplitude and slope of the triangle wave at the start of the event interval and a second digital value of the amplitude and slope of the triangle wave at the end of the event interval. A counter counts the clock pulse train during the interval to form a gross event interval time. A computer then combines the gross event interval time and the first and second digital values to output a high resolution value for the event interval.
Date:
December 31, 1992
Creator:
Thornton, G. W. & Fuller, K. R.
System:
The UNT Digital Library
Production of aluminum-26
This invention is a method of producing Al-26 from potassium chloride by exposing it to a proton beam in order to break potassium and chlorine atoms into smaller pieces, which include Al-26. The Al-26 is isolated from the potassium chloride and substances produced by the beam by means of extraction and ion exchange.
Date:
December 31, 1990
Creator:
Steinkruger, F. J. & Phillips, D. R.
System:
The UNT Digital Library
Preventive maintenance system for the photomultiplier detector blocks of pet scanners
The present invention relates to a system for the preventive maintenance of the Photomultiplier Detector Blocks of PET Scanners. This system is used to automatically indicate the expected date of failure of a photomultiplier detector block and provide time for its replacement and maintenance in a scheduled preventive maintenance program, thus eliminating expensive unscheduled downtime of a PET Scanner due to photomultiplier failure.
Date:
December 31, 1992
Creator:
Levy, A. V. & Warner, D.
System:
The UNT Digital Library
Tritium extraction furnace
This invention is comprised of apparatus for heating an object such as a nuclear target bundle to release and recover hydrogen and contain the disposable residue for disposal. The apparatus comprises an inverted furnace, a sleeve/crucible assembly for holding and enclosing the bundle, conveying equipment for placing the sleeve onto the crucible and loading the bundle into the sleeve/crucible, a lift for raising the enclosed bundle into the furnace, and hydrogen recovery equipment including a trap and strippers, all housed in a containment having, negative internal pressure. The crucible/sleeve assembly has an internal volume that is sufficient to enclose and hold the bundle before heating; the crucible`s internal volume is sufficient by itself to hold and enclose the bundle`s volume after heating. The crucible can then be covered and disposed of, the sleeve, on the other hand, can be reused.
Date:
December 31, 1992
Creator:
Heung, L. K.
System:
The UNT Digital Library
Process for forming one or more substantially pure layers in substrate material using ion implantation
The method comprises selecting an implantable element and a substrate material to be implanted which, at the implant/anneal temperatures, have limited mutual solubility and have no intermediate phases formed. In an example, Be is implanted with 11 {times}10{sup 17} Al/cm{sup 2} at 200 keV and then annealed for 1 h at 500 C. Rutherford backscattering shows that layer formation occurred during the anneal. SEM shows rectangular Be defects in the Al layer. Other examples of implantable elements and suitable substrate materials are tabulated. 6 figs, 1 table. (DLC)
Date:
December 31, 1990
Creator:
Musket, R. G.; Brown, D. W. & Munir, Z. A.
System:
The UNT Digital Library
Supported liquid membrane system
A cell apparatus for a supported liquid membrane including opposing faceplates, each having a spirally configured groove, an inlet groove at a first end of the spirally configured groove, and an outlet groove at the other end of the spirally configured groove, within the opposing faces of the faceplates, a microporous membrane situated between the grooved faces of the faceplates, said microporous membrane containing an extractant mixture selective for a predetermined chemical species within the pores of said membrane, means for aligning the grooves of the faceplates in an directly opposing configuration with the porous membrane being situated therebetween, such that the aligned grooves form a pair of directly opposing channels, separate feed solution and stripping solution compartments connected to respective channels between the faceplates and the membrane, separate pumping means for passing feed solution and stripping solution through the channels is provided.
Date:
December 31, 1990
Creator:
Takigawa, D. Y. & Bush, H. Jr.
System:
The UNT Digital Library
Method and system for enhancing microbial motility
A method and system for enhancing the motility of microorganisms by placing an effective amount of chlorinated hydrocarbons, preferably chlorinated alkenes, and most preferably trichloroethylene in spaced relation to the microbes so that the surprisingly strong, monomodal, chemotactic response of the chlorinated hydrocarbon on subsurface microbes can draw the microbes away from or towards and into a substance, as desired. In remediation of groundwater pollution, for example, TCE can be injected into the plume to increase the population of microbes at the plume whereby the plume can be more quickly degraded. A TCE-degrading microbe, such as Welchia alkenophilia, can be used to degrade the TCE following the degradation of the original pollutant.
Date:
December 31, 1992
Creator:
Hazen, T. C. & Lopez-De-Victoria, G.
System:
The UNT Digital Library
Radiation detector using a bulk high {Tc} superconductor
A radiation detector is provided, wherein a bulk high T superconducting sample is placed in a magnetic field and maintained at a superconducting temperature. Photons of incident radiation will cause localized heating in superconducting loops of the sample destroying trapped flux and redistributing the fluxons, and reducing the critical current of the loops. Subsequent cooling of the sample in the magnetic field will cause trapped flux redistributed Abrikosov fluxons and trapped Josephson fluxons. The destruction and trapping of the fluxons causes changes in the magnetization of the sample inducing currents in opposite directions in a pickup coil which is coupled by an input coil to an rf SQUID).
Date:
December 31, 1992
Creator:
Artusom, J. F.; Franks, L. A.; Hull, K. L. & Symko, O. G.
System:
The UNT Digital Library
Analysis of hydrogen isotope mixtures
Disclosed are an apparatus and a method for determining concentrations of hydrogen isotopes in a sample. Hydrogen in the sample is separated from other elements using a filter selectively permeable to hydrogen. Then the hydrogen is condensed onto a cold finger or cryopump. The cold finger is rotated as pulsed laser energy vaporizes a portion of the condensed hydrogen, forming a packet of molecular hydrogen. The desorbed hydrogen is ionized and admitted into a mass spectrometer for analysis.
Date:
December 31, 1992
Creator:
Villa-Aleman, E.
System:
The UNT Digital Library
Velocity damper for electromagnetically levitated materials
A system for damping oscillatory and spinning motions induced in an electromagnetically levitated material. Two opposed field magnets are located orthogonally to the existing levitation coils for providing a DC quadrupole field (cusp field) around the material. The material used for generating the DC quadrupole field must be nonconducting to avoid eddy-current heating and of low magnetic permeability to avoid distorting the induction fields providing the levitation.
Date:
December 31, 1992
Creator:
Fox, R. J.
System:
The UNT Digital Library
Waste treatment process for removal of contaminants from aqueous, mixed-waste solutions using sequential chemical treatment and crossflow microfiltration, followed by dewatering
It is an object of the claimed invention to combine chemical treatment with microfiltration process to treat groundwater, leachate from contaminated soil washing, surface and run-off waters contaminated with toxic metals, radionuclides and trace amounts of organics from variety of sources. The process can also be used to treat effluents from industrial processes such as discharges associated with smelting, mining and refining operations. Influent contaminants amenable to treatment are from a few mg/L to hundreds of mg/L. By selecting appropriate precipitation, ion exchange and adsorption agents and conditions, efficiencies greater than 99.9 percent can be achieved for removal of contaminants. The filtered water for discharge can be targeted with either an order of magnitude greater or lower than contaminant levels for drinking water.
Date:
December 31, 1992
Creator:
Vijayan, S.; Wong, Chi Fun & Buckley, L. P.
System:
The UNT Digital Library
Extrusion of metal oxide superconducting wire, tube or ribbon
A process and apparatus for extruding a superconducting metal oxide composition YBa{sub 2}Cu{sub 3}O{sub 7-x} provides a wire (tube or ribbon) having a cohesive mass and a degree of flexibility together with enhanced electrical properties. Wire diameters in the range of 6--85 mils have been produced with smaller wires on the order of 10 mils in diameter exhibiting enhanced flexibility for forming braided, or multistrand, configurations for greater current carrying capacity. The composition for extrusion contains a polymeric binder to provide a cohesive mass to bind the particles together during the extrusion process with the binder subsequently removed at lower temperatures during sintering. The composition for extrusion further includes a deflocculent, an organic plasticizer and a solvent which also are subsequently removed during sintering. Electrically conductive tubing with an inner diameter of 52 mil and an outer diameter of 87--335 mil has also been produced. Flat ribbons have been produced in the range of 10--125 mil thick by 100--500 mil wide. The superconducting wire, tube or ribbon may include an outer ceramic insulating sheath co-extruded with the wire, tubing or ribbon.
Date:
December 31, 1990
Creator:
Dusek, Joseph T.
System:
The UNT Digital Library
Non-linear optical crystal vibration sensing device
The report describes a non-linear optical crystal vibration sensing device including a photorefractive crystal and a laser. The laser produces a coherent light beam which is split by a beam splitter into a first laser beam and a second laser beam. After passing through the crystal the first laser beam is counter-propagated back upon itself by a retro-mirror, creating a third laser beam . The laser beams are modulated, due to the mixing effect within the crystal by vibration of the crystal. In the third laser beam modulation is stable and such modulation is converted by a photodetector into a usable electrical output, intensity modulated in accordance with vibration applied to the crystal.
Date:
December 31, 1992
Creator:
Kalibjian, R.
System:
The UNT Digital Library
A pulverized coal fuel injector
A pulverized coal fuel injector contains an acceleration section to improve the uniformity of a coal-air mixture to be burned. An integral splitter is provided which divides the coal-air mixture into a number separate streams or jets, and a center body directs the streams at a controlled angle into the primary zone of a burner. The injector provides for flame shaping and the control of NO/NO{sub 2} formation.
Date:
December 31, 1991
Creator:
Rini, M. J. & Towle, D. P.
System:
The UNT Digital Library
Bioremediation of contaminated groundwater
The present invention relates to a method for in situ bioremediation of contaminated soil and groundwater. In particular, the invention relates to remediation of contaminated soil and groundwater by the injection of nutrients to stimulate growth of pollutant-degrading microorganisms. The United States Government has rights in this invention pursuant to Contract No. DE-AC09-89SR18035 between the US Department of Energy and Westinghouse Savannah River Company.
Date:
December 31, 1992
Creator:
Hazen, T. C. & Fliermans, C. B.
System:
The UNT Digital Library
Clay enhancement of methane, low molecular weight hydrocarbon and halocarbon conversion by methanotrophic bacteria
The invention described in this report relates to a combined system of an apparatus and a method of increasing the rates of oxidation of gases and hazardous vapors by methanotrophic and other bacteria. The gases of interest are methane and trichlorethylene and other hazardous vapors. In a preferred embodiment, the oxidation rate of methane is improved by the addition of clays, e.g., kaolin, sometimes called ``China clay.``
Date:
December 31, 1991
Creator:
Apel, W. A. & Dugan, P. R.
System:
The UNT Digital Library
Method for distinguishing normal and transformed cells using G1 kinase inhibitors
A G{sub 1} phase kinase inhibitor is applied in a low concentration to a population of normal and transformed mammalian cells. The concentration of G{sub 1} phase kinase inhibitor is selected to reversibly arrest normal mammalian cells in the G{sub 1} cell cycle without arresting growth of transformed cells. The transformed cells may then be selectively identified and/or cloned for research or diagnostic purposes. The transformed cells may also be selectively killed by therapeutic agents that do not affect normal cells in the G{sub 1} phase, suggesting that such G{sub 1} phase kinase inhibitors may form an effective adjuvant for use with chemotherapeutic agents in cancer therapy for optimizing the killing dose of chemotherapeutic agents while minimizing undesirable side effects on normal cells.
Date:
December 31, 1991
Creator:
Crissman, H. A.; Gadbois, D. M.; Tobey, R. A. & Bradbury, E. M.
System:
The UNT Digital Library