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Acyclonucleosides of 2-nitroimidazole and uses as diagnostic and therapeutic agents (open access)

Acyclonucleosides of 2-nitroimidazole and uses as diagnostic and therapeutic agents

An acyclonucleoside of nitroimidazole having the ability to specifically bind to tumor cells and useful for therapy, chemotherapy, imaging and radiosensitizing the tumor cells.
Date: January 1, 1990
Creator: Srivastava, P.C. & Hasan, A.
System: The UNT Digital Library
Counterrotating brushless dc permanent magnet motor (open access)

Counterrotating brushless dc permanent magnet motor

An brushless DC permanent magnet motor is provided for driving an autonomous underwater vehicle. In one embodiment, the motor comprises four substantially flat stators disposed in stacked relationship, with pairs of the stators being axially spaced and each of the stators comprising a tape-wound stator coil; and a first and second substantially flat rotors disposed between the spaced pairs of stators. Each of the rotors includes an annular array of permanent magnets embedded therein. A first shaft is connected to the first rotor and a second, concentric shaft is connected to the second rotor, and drive unit causes rotation of the two shafts in opposite directions. The second shaft comprises a hollow tube having a central bore therein in which the first shaft is disposed. Two different sets of bearings support the first and second shAfts. In another embodiment, the motor comprises two ironless stators and pairs and rotors mounted no opposite sides of the stators and driven by counterrotating shafts.
Date: January 1, 1990
Creator: Hawsey, R. A. & Bailey, J. M.
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: January 1, 1990
Creator: Dusek, J.T.
System: The UNT Digital Library
Improved thermal storage module for solar dynamic receivers (open access)

Improved thermal storage module for solar dynamic receivers

This invention relates to a thermal storage apparatus and more particularly to an apparatus for use in conjunction with solar dynamic energy storage systems. The invention is comprised of a thermal energy storage system comprising a germanium phase change material and a graphite container.
Date: January 1, 1990
Creator: Beatty, R. L. & Lauf, R. J.
System: The UNT Digital Library
A method and apparatus for continuous electrophoresis (open access)

A method and apparatus for continuous electrophoresis

A method and apparatus for conducting continuous separation of substances by electrophoresis are disclosed. The process involves electrophoretic separation combined with couette flow in a thin volume defined by opposing surfaces. By alternating the polarity of the applied potential and producing reciprocating short rotations of at least on of the surfaces relative to the other, small increments of separation accumulate to cause substantial, useful segregation of electrophoretically separable components in a continuous flow system.
Date: January 1, 1990
Creator: Watson, J. S.
System: The UNT Digital Library
Passive decay heat removal system for water-cooled nuclear reactors (open access)

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: January 1, 1990
Creator: Forseberg, C.W.
System: The UNT Digital Library
Process of converting starch to glucose and glucose to lactic acid (open access)

Process of converting starch to glucose and glucose to lactic acid

This document describes a method for converting starch into lactic acid of sufficient purity for use as a substrate for biodegradable plastics. The process is designed to work on industrial food waste streams such as potato wastes or cheese whey permeate. For potato waste, {alpha}-amylase and calcium chloride are added to the starch containing waste and incubated at a pH of 4--7, a temperature of 90--130{degree}C, and a pressure above 15 psi for not less than 15 minutes. At this point, glucoamylase is added and the mixture is incubated at a temperature of 50--70{degree}C and a pH below 6.5 for 4 hours. This results in the conversion of more than 90% of the starch into glucose, which is substantially free of microbial contamination. The hydrolysate is filtered, and introduced with additional nutrients to a fermentor containing a lactose producing microorganism to form a fermentation broth. This results in the fermentation of glucose to lactose, which is filtered and subjected to electrodialysis for purification. Conversion of glucose to lactic acid or lactate occurs with an efficiency of over 95%. 1 fig. (MHB)
Date: January 1, 1990
Creator: Tsai, TenLin; Sanville, Cynthia Y.; Coleman, Robert D. & Schertz, William W.
System: The UNT Digital Library
Solid-state NMR imaging system (open access)

Solid-state NMR imaging system

An accessory for use with a solid-state NMR spectrometer includes a special imaging probe with linear, high-field strength gradient fields and high-power broadband RF coils using a back projection method for data acquisition and image reconstruction, and a real-time pulse programmer adaptable for use by a conventional computer for complex high speed pulse sequences.
Date: January 1, 1990
Creator: Gopalsami, N.; Dieckman, S.L. & Ellingson, W.A.
System: The UNT Digital Library
A Stripline Fast Faraday Cup for measuring GHz structure of ion beams (open access)

A Stripline Fast Faraday Cup for measuring GHz structure of ion beams

The Stripline Fast Faraday Cup is a device which is used to quantitatively and qualitatively measure gigahertz time structure characteristics of ion beams with energies up to at least 30 Mev per nucleon. A stripline geometry is employed in conjunction with an electrostatic screen and a Faraday cup to provide for analysis of the structural characteristics of an ion beam. The stripline geometry allows for a large reduction in the size of the instrument while the electrostatic screen permits measurements of the properties associated with low speed ion beams.
Date: January 1, 1990
Creator: Bogaty, J. M.
System: The UNT Digital Library
Triaxial thermopile array geo-heat-flow sensor (open access)

Triaxial thermopile array geo-heat-flow sensor

A triaxial thermopile array geothermal heat flow sensor is designed to measure heat flow in three dimensions in a reconstituted or unperturbed subsurface regime. Heat flow can be measured in conductive or permeable convective media. The sensor may be encased in protective pvc tubing and includes a plurality of thermistors and an array of heat flow transducers produce voltage proportional to heat flux along the subsurface regime and permit direct measurement of heat flow in the subsurface regime. The presence of the thermistor array permits a comparison to be made between the heat flow estimates obtained from the transducers and heat flow calculated using temperature differences and Fourier's Law. The device is extremely sensitive with an accuracy of less than 0.1 Heat Flow Units (HFU) and may be used for long term readings. 6 figs.
Date: January 1, 1990
Creator: Carrigan, Charles R.; Hardee, Harold C.; Reynolds, Gerald D. & Steinfort, Terry D.
System: The UNT Digital Library
Wedge assembly for electrical transformer component spacing (open access)

Wedge assembly for electrical transformer component spacing

This invention is comprised of a wedge assembly that is easily inserted between two surface to be supported thereby, and thereafter expanded to produce a selected spacing between those surfaces. This wedge assembly has two outer members that are substantially identical except that they are mirror images of each other. Oppositely directed faces of these of these outer members are substantially parallel for the purpose of contacting the surfaces to be separated. The other faces of these outer members that are directed toward each other are tapered so as to contact a center member having complementary tapers on both faces. A washer member is provided to contact a common end of the outer members, and a bolt member penetrates this washer and is threadably received in a receptor of the center member. As the bolt member is threaded into the center member, the center member is drawn further into the gap between the outer members and thereby separates these outer members to contact the surfaces to be separated. In the preferred embodiment, the contacting surfaces of the outer member and the center member are provided with guide elements. The wedge assembly is described for use in separating the secondary windings …
Date: January 1, 1990
Creator: Baggett, F.E. & Cage, W.F.
System: The UNT Digital Library
Processing method for superconducting ceramics (open access)

Processing method for superconducting ceramics

A process for preparing a superconducting ceramic and particularly YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}, where {delta} is in the order of about 0.1--0.4, is carried out using a polymeric binder which decomposes below its ignition point to reduce carbon residue between the grains of the sintered ceramic and a nonhydroxylic organic solvent to limit the problems with water or certain alcohols on the ceramic composition.
Date: May 7, 1990
Creator: Bloom, I. D.; Poeppel, R. B. & Flandermeyer, B. K.
System: The UNT Digital Library
Setting-Basin Separating Device (open access)

Setting-Basin Separating Device

Patent for Settling Basin-Separating Devices. This device improves the issue of unwanted discharge shown in prior devices
Date: May 11, 1990
Creator: Allen, Charles
System: The Portal to Texas History
A unique system of Fe/Pd for magneto-optical recording and magnetic switching devices (open access)

A unique system of Fe/Pd for magneto-optical recording and magnetic switching devices

This invention is comprised of a high density magneto-optical information storage medium utilizing the properties of an ultrathin iron film on a palladium substrate. The present invention comprises a magneto-optical medium capable of thermal and magnetic stability and capable of possessing a vertical orientation of the magnetization vector for the magnetic material. Data storage relies on the temperature dependence of the coercivity of the ultrathin film. Data retrieval derives from the Kerr effect which describes the direction of rotation of a plane of polarized light traversing the ultrathin magnetic material as a function of the orientation of the magnetization vector.
Date: May 22, 1990
Creator: Liu, Chian Q. & Bader, S. D.
System: The UNT Digital Library
A unique system of Fe/Pd for magneto-optical recording and magnetic switching devices (open access)

A unique system of Fe/Pd for magneto-optical recording and magnetic switching devices

This invention is comprised of a high density magneto-optical information storage medium utilizing the properties of an ultrathin iron film on a palladium substrate. The present invention comprises a magneto-optical medium capable of thermal and magnetic stability and capable of possessing a vertical orientation of the magnetization vector for the magnetic material. Data storage relies on the temperature dependence of the coercivity of the ultrathin film. Data retrieval derives from the Kerr effect which describes the direction of rotation of a plane of polarized light traversing the ultrathin magnetic material as a function of the orientation of the magnetization vector.
Date: May 22, 1990
Creator: Liu, Chian Q. & Bader, S. D.
System: The UNT Digital Library
Method of solubilizing phthalocyanines and metallophthalocyanines (open access)

Method of solubilizing phthalocyanines and metallophthalocyanines

A one-step method of manufacturing soluble phthalocyanines and metallophthalocyanines, like zinc phthalocyanine, by converting a phthalocyanine or a metallophthalocyanine to a trialkylsilyl-substituted derivative is disclosed. The phthalocyanine or metallophthalocyanine is converted to a soluble trialkylsilyl-substituted derivative by interacting the phthalocyanine or metallophthalocyanine with an active metal amide, like lithium 2,2,6, 6-tetra-methylpiperidide, and a halotrialkylsilane, like chlorotrimethylsilane, to provide a phthalocyanine compound, like phthalocyanine monomers, dimers or polymers, metalated or unmetalated, that are soluble in organic media.
Date: June 1, 1990
Creator: Rathke, J. W.; Chen, M. J. & Fendrick, C. M.
System: The UNT Digital Library
Method of solubilizing phthalocyanines and metallophthalocyanines (open access)

Method of solubilizing phthalocyanines and metallophthalocyanines

A one-step method of manufacturing soluble phthalocyanines and metallophthalocyanines, like zinc phthalocyanine, by converting a phthalocyanine or a metallophthalocyanine to a trialkylsilyl-substituted derivative is disclosed. The phthalocyanine or metallophthalocyanine is converted to a soluble trialkylsilyl-substituted derivative by interacting the phthalocyanine or metallophthalocyanine with an active metal amide, like lithium 2,2,6, 6-tetra-methylpiperidide, and a halotrialkylsilane, like chlorotrimethylsilane, to provide a phthalocyanine compound, like phthalocyanine monomers, dimers or polymers, metalated or unmetalated, that are soluble in organic media.
Date: June 1, 1990
Creator: Rathke, Jerome W.; Chen, Michael J. & Fendrick, Carol M.
System: The UNT Digital Library
Water and UV degradable lactic acid polymers (open access)

Water and UV degradable lactic acid polymers

A water and UV light degradable copolymer of monomers of lactic acid and a modifying monomer selected from the class consisting of ethylene and polyethylane glycols (PVB 6/22/90), propylene and and polypropylene (PVB 6/22/90) glycols, P-dioxanone, 1, 5 dioxepan-2-one, 1,4 -oxathialan-2-one, 1,4-dioxide and mixtures thereof. These copolymers are useful for waste disposal and agricultural purposes. Also disclosed is a water degradable blend of polylactic acid or modified polylactic acid and high molecular weight polyethylene oxide wherein the high molecular weight polyethylene oxide is present in the range of from about 2% by weight to about 50% by weight, suitable for films. A method of applying an active material selected from the class of seeds, seedlings, pesticides, herbicides, fertilizers and mixtures thereof to an agricultural site is also disclosed.
Date: June 26, 1990
Creator: Bonsignore, P. V. & Coleman, R. D.
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 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, Tuncer M.
System: The UNT Digital Library
Highly conductive electrolyte composites and method of fabrication thereof (open access)

Highly conductive electrolyte composites and method of fabrication thereof

An electrolyte composite is manufactured by pressurizing a mixture of ionically conductive glass and an ionically conductive compound at between 12,000 and 24,000 pounds per square inch to produce a pellet. The resulting pellet is then sintered at relatively lower temperatures (800{degrees}C--1200{degrees}C), for example 1000{degrees}C, than are typically required (1400{degrees}C) when fabricating single constituent ceramic electrolytes. The resultant composite is 100 percent conductive at 250{degrees}C with conductivity values of 2.5 to 4 {times} 10{sup {minus}2} (ohm-cm){sup {minus}1}. The matrix exhibits chemical stability against sodium for 100 hours at 250 to 300{degrees}C.
Date: July 17, 1990
Creator: Hash, M. C. & Bloom, I. D.
System: The UNT Digital Library
Process for fabrication of metal oxide films (open access)

Process for fabrication of metal oxide films

This invention is comprised of a method of fabricating metal oxide films from a plurality of reactants by inducing a reaction by plasma deposition among the reactants. The plasma reaction is effective for consolidating the reactants and producing thin films of metal oxides, e.g. electro-optically active transition metal oxides, at a high deposition rate. The presence of hydrogen during the plasma reaction enhances the deposition rate of the metal oxide. Various types of metal oxide films can be produced.
Date: July 17, 1990
Creator: Tracy, C. E.; Benson, D. & Svensson, S.
System: The UNT Digital Library
Background-reducing x-ray multilayer mirror (open access)

Background-reducing x-ray multilayer mirror

This invention is comprised of a background-reducing x-ray multilayer mirror. A multiple-layer ``wavetrap`` deposited over the surface of a layered synthetic microstructure soft x-ray mirror optimized for reflectivity at chosen wavelengths is disclosed for reducing the reflectivity of undesired, longer wavelength incident radiation incident thereon. In three separate mirror designs employing an alternating molybdenum and silicon layered mirrored structure overlaid by two layers of a molybdenum/silicon pair anti-reflection coating, reflectivities of near normal incidence 133, 171, and 186 {Angstrom} wavelengths have been optimized, while that at 304 {Angstrom} has been minimized. The optimization process involves the choice of materials, the composition of the layer/pairs as well as the number thereof, and the distance therebetween for the mirror, and the simultaneous choice of materials, the composition of the layer/pairs, their number and distance for the ``wavetrap.``
Date: August 3, 1990
Creator: Bloch, J. J.; Roussel-Dupre, D. & Smith, B. W.
System: The UNT Digital Library
Ductile nickel-silicon alloy (open access)

Ductile nickel-silicon alloy

An improvement over prior compositions wherein the ductility of Ni-Si alloys are improved with minor alloying additions of hafnium or zirconium.
Date: August 6, 1990
Creator: Oliver, W. C.
System: The UNT Digital Library