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Production of aluminum-26 (open access)

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 (open access)

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 (open access)

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 of making cryogenically cooled high thermal performance crystal optics (open access)

Process of making cryogenically cooled high thermal performance crystal optics

A method for constructing a cooled optic wherein one or more cavities are milled, drilled or formed using casting or ultrasound laser machining techniques in a single crystal base and filled with porous material having high thermal conductivity at cryogenic temperatures. A non-machined strain-free single crystal can be bonded to the base to produce superior optics. During operation of the cooled optic, N{sub 2} is pumped through the porous material at a sub-cooled cryogenic inlet temperature and with sufficient system pressure to prevent the fluid bulk temperature from reaching saturation.
Date: June 29, 1990
Creator: Kuzay, T. M.
System: The UNT Digital Library
Process for forming one or more substantially pure layers in substrate material using ion implantation (open access)

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 (open access)

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 (open access)

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 (open access)

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 (open access)

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 (open access)

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 (open access)

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 (open access)

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 (open access)

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 (open access)

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 (open access)

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
High current pulse transmission cable (open access)

High current pulse transmission cable

This invention is comprised of a transmission cable for carrying high current pulses in which an even numbered plurality of electrical conductors surrounds a central ground conductor. Each electrical conductor is connected so that it at any instant in time it will carry current of opposite polarity to the polarity carried by adjacent conductors. This arrangement cancels practically all of the external fields generated by current in the conductors.
Date: September 28, 1990
Creator: Parsons, W. M.
System: The UNT Digital Library
Clay enhancement of methane, low molecular weight hydrocarbon and halocarbon conversion by methanotrophic bacteria (open access)

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 (open access)

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
Molybdenum disilicide composites reinforced with zirconia and silicon carbide (open access)

Molybdenum disilicide composites reinforced with zirconia and silicon carbide

This patent pertains to compositions consisting essentially of molybdenum disilicide, silicon carbide, and a zirconium oxide component. The silicon carbide used in the compositions is in whisker or powder form. The zirconium oxide component is pure zirconia or partially stabilized zirconia or fully stabilized zirconia. Fabrication, fracture toughness, and bend strength are covered.
Date: December 31, 1992
Creator: Petrovic, J. J.
System: The UNT Digital Library
Reflective Optical Imaging System for Extreme Ultraviolet Wavelengths (open access)

Reflective Optical Imaging System for Extreme Ultraviolet Wavelengths

This invention is comprised of a projection reflection optical system having two mirrors in a coaxial, four reflection configuration to reproduce the image of an object. The mirrors have aspherical reflection surfaces to provide a very high resolution of object feature wavelengths less than 200 {mu}m, and preferably less than 100 {mu}m. An image resolution of features less than 0.05--0.1 {mu}m, is obtained over a large area field; i.e., 25.4 mm {times} 25.4 mm, with a distortion less than 0.1 of the resolution over the image field.
Date: December 31, 1991
Creator: Viswanathan, V. K. & Newnam, B. E.
System: The UNT Digital Library
No-carrier-added (NCA) aryl [{sup 18}F]fluorides via the nucleophilic aromatic substitution of electron rich aromatic rings (open access)

No-carrier-added (NCA) aryl [{sup 18}F]fluorides via the nucleophilic aromatic substitution of electron rich aromatic rings

A method for synthesizing no-carrier-added (NCA) aryl [{sup 18}F] fluoride substituted aromatic aldehyde compositions bearing an electron donating group is described. The method includes the step of reacting aromatic nitro aldehydes having a suitably protected hydroxyl substituent on an electron rich ring. The reaction is carried out by nucleophilic aromatic substitution with a no-carrier-added (NCA) [{sup 18}F]fluoride ion. The method can be used to synthesize various no-carrier-added aryl [{sup 18}F]fluoride compositions, including 6-[{sup 18}F]fluoro-L-DOPA, 2-[{sup 18}F]fluorotyrosine, 6-[{sup 18}F]fluoronorepinephrine, and 6-[{sup 18}F]fluorodopamine. In those instances when a racemic mixture of enantiomers is produced by the present invention, such as in the synthesis of 6-[{sup 18}F]fluoronorepinephrine, a preferred method also includes resolution of the racemic mixture on a chiral HPLC column. This procedure results in a high yield of enantiomerically pure [{sup 18}F] labeled isomers, for example [-]-6-[{sup 18}F]fluoronorepinephrine and [+]-6-[{sup 18}F]fluoronorepinephrine.
Date: December 31, 1991
Creator: Ding, Yu-Shin; Fowler, J. S. & Wolf, A. P.
System: The UNT Digital Library
Process for alloying uranium and niobium (open access)

Process for alloying uranium and niobium

Alloys such as U-6Nb are prepared by forming a stacked sandwich array of uranium sheets and niobium powder disposed in layers between the sheets, heating the array in a vacuum induction melting furnace to a temperature such as to melt the uranium, holding the resulting mixture at a temperature above the melting point of uranium until the niobium dissolves in the uranium, and casting the uranium-niobium solution. Compositional uniformity in the alloy product is enabled by use of the sandwich structure of uranium sheets and niobium powder.
Date: December 31, 1990
Creator: Holcombe, Cressie E.; Northcutt, Walter G.; Masters, David R. & Chapman, Lloyd R.
System: The UNT Digital Library
Simplified flangeless unisex waveguide coupler assembly (open access)

Simplified flangeless unisex waveguide coupler assembly

A unisex coupler assembly is disclosed capable of providing a leak tight coupling for waveguides with axial alignment of the waveguides and rotational capability. The sealing means of the coupler assembly are not exposed to RF energy, and the coupler assembly does not require the provision of external flanges on the waveguides. In a preferred embodiment, O ring seals are not used and the coupler assembly is, therefore, bakeable at a temperature up to about 150{degrees}C. The coupler assembly comprises a split collar which clamps around the waveguides and a second collar which fastens to the split collar. The split collar contains an inner annular groove. Each of the waveguides is provided with an external annular groove which receives a retaining ring. The split collar is clamped around one of the waveguides with the inner annular groove of the split collar engaging the retaining ring carried in the external annular groove in the waveguide. The second collar is then slipped over the second waveguide behind the annular groove and retaining ring therein and the second collar is coaxially secured by fastening means to the split collar to draw the respective waveguides together by coaxial force exerted by the second collar …
Date: December 31, 1992
Creator: DiMartino, M. & Moeller, C. P.
System: The UNT Digital Library
Jet plume injection and combustion system for internal combustion engines (open access)

Jet plume injection and combustion system for internal combustion engines

This invention is comprised of an improved combustion system for an internal combustion engine is disclosed wherein a rich air/fuel mixture is furnished at high pressure to one or more jet plume generator cavities adjacent to a cylinder and then injected through one or more orifices from the cavities into the head space of the cylinder to form one or more turbulent jet plumes in the head space of the cylinder prior to ignition of the rich air/fuel mixture in the cavity of the jet plume generator. The portion of the rich air/fuel mixture remaining in the cavity of the generator is then ignited to provide a secondary jet, comprising incomplete combustion products which are injected into the cylinder to initiate combustion in the already formed turbulent jet plume. Formation of the turbulent jet plume in the head space of the cylinder prior to ignition has been found to yield a higher maximum combustion pressure in the cylinder, as well as shortening the time period to attain such a maximum pressure.
Date: December 31, 1992
Creator: Oppenheim, A. K.; Maxson, J. A. & Hensinger, D. M.
System: The UNT Digital Library