/sup 18/F-4-fluoroantipyrine (open access)

/sup 18/F-4-fluoroantipyrine

The novel radioactive compound /sup 18/F-4-fluoroantipyrine having high specific activity which can be used in nuclear medicine in diagnostic applications, prepared by the direct fluorination of antipyrine in acetic acid with radioactive fluorine at room temperature and purifying said radioactive compound by means of gel chromatography with ethyl acetate as eluent is disclosed. The non-radioactive 4-fluoroantipyrine can also be prepared by the direct fluorination of antipyrine in acetic acid with molecular fluorine at room temperature and purified by means of gel chromatography with ethyl acetate eluent.
Date: January 1, 1980
Creator: Shiue, Chyng-Ysnn & Wolf, Alfred P.
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
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
Pressure gradient passivation of carbonaceous material normally susceptible to spontaneous combustion (open access)

Pressure gradient passivation of carbonaceous material normally susceptible to spontaneous combustion

This invention is a process for the passivation or deactivation with respect to oxygen of a carbonaceous material by the exposure of the carbonaceous material to an oxygenated gas in which the oxygenated gas pressure is increased from a first pressure to a second pressure and then the pressure is changed to a third pressure. Preferably a cyclic process which comprises exposing the carbonaceous material to the gas at low pressure and increasing the pressure to a second higher pressure and then returning the pressure to a lower pressure is used. The cycle is repeated at least twice wherein the higher pressure may be increased after a selected number of cycles.
Date: January 29, 2002
Creator: Ochs, Thomas L.; Sands, William D.; Schroeder, Karl; Summers, Cathy A. & Utz, Bruce R.
System: The UNT Digital Library
Apparatus and Method for Increasing the Diameter of Metal Alloy Wires Within a Molten Metal Pool (open access)

Apparatus and Method for Increasing the Diameter of Metal Alloy Wires Within a Molten Metal Pool

In a dip forming process the core material to be coated is introduced directly into a source block of coating material eliminating the need for a bushing entrance component. The process containment vessel or crucible is heated so that only a portion of the coating material becomes molten, leaving a solid portion of material as the entrance port of, and seal around, the core material. The crucible can contain molten and solid metals and is especially useful when coating core material with reactive metals. The source block of coating material has been machined to include a close tolerance hole of a size and shape to closely fit the core material. The core material moves first through the solid portion of the source block of coating material where the close tolerance hole has been machined, then through a solid/molten interface, and finally through the molten phase where the diameter of the core material is increased. The crucible may or may not require water-cooling depending upon the type of material used in crucible construction. The system may operate under vacuum, partial vacuum, atmospheric pressure, or positive pressure depending upon the type of source material being used.
Date: January 29, 2002
Creator: Hartman, Alan D.; Argetsinger, Edward R.; Hansen, Jeffrey S.; Paige, Jack I.; King, Paul E. & Turner, Paul C.
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
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
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
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
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
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
Free-electron-laser design for laser amplification (open access)

Free-electron-laser design for laser amplification

A method for laser beam amplification by means of free electron laser techniques is described. With wiggler magnetic field strength B/sub w/ and wavelength lambda/sub w/ = 2..pi../k/sub w/ regarded as variable parameters, the method(s) impose conditions such as substantial constancy of B/sub w//k/sub w/ or k/sub w/ or B/sub w/ and k/sub w/ (alternating), coupled with a choice of either constant resonant phase angle or programmed phase space bucket area.
Date: January 26, 1982
Creator: Prosnitz, D. & Szoke, A.
System: The UNT Digital Library
Circular free-electron laser (open access)

Circular free-electron laser

A high efficiency, free electron laser is described utilizing a circular relativistic electron beam accelerator and a circular whispering mode optical waveguide for guiding optical energy in a circular path in the circular relativistic electron beam accelerator such that the circular relativistic electron beam and the optical energy are spatially contiguous in a resonant condition for free electron laser operation. Both a betatron and synchrotron are disclosed for use in the present invention. A free electron laser wiggler is disposed around the circular relativistic electron beam accelerator for generating a periodic magnetic field to transform energy from the circular relativistic electron beam to optical energy.
Date: January 26, 1982
Creator: Brau, Charles A.; Kurnit, Norman A. & Cooper, Richard K.
System: The UNT Digital Library
Slag capture and removal during laser cutting. [Patent application] (open access)

Slag capture and removal during laser cutting. [Patent application]

Molten metal removed from a workpiece in a laser cutting operation is blown away from the cutting point by a gas jet and collected on an electromagnet. The laser cutting is used to separate the castings of spent fuel rods from the fuel-containing elements therein.
Date: January 28, 1982
Creator: Brown, C.O.
System: The UNT Digital Library
Clamshell tomograph (open access)

Clamshell tomograph

The invention is a tomograph modified to be in a clamshell configuration so that the ring or rings may be moved to multiple sampling positions. The tomograph includes an array of detectors arranged in successive adjacent relative locations along a closed curve in a first position in a selected plane, and means for securing the detectors in the relative locations in a first sampling position. The securing means is movable in the plane in two sections and pivotable at one point and only one point to enable movement of at least one of the sections to a second sampling position out of the closed curve so that the ends of the section which are opposite the point are moved apart a predetermined space.
Date: January 29, 1982
Creator: Derenzo, S.E. & Budinger, T.F.
System: The UNT Digital Library
All ceramic structure for molten carbonate fuel cell (open access)

All ceramic structure for molten carbonate fuel cell

An all-ceramic molten carbonate fuel cell having a composition formed of a multivalent metal oxide or oxygenate such as an alkali metal, transition metal oxygenate. The structure includes an anode and cathode separated by an electronically conductive interconnect. The electrodes and interconnect are compositions ceramic materials. Various combinations of ceramic compositions for the anode, cathode and interconnect are disclosed. The fuel cell exhibits stability in the fuel gas and oxidizing environments. It presents reduced sealing and expansion problems in fabrication and has improved long-term corrosion resistance.
Date: January 1, 1991
Creator: Smith, James L. & Kucera, Eugenia H.
System: The UNT Digital Library
Photosensitivity enhancement of PLZT ceramics by positive-ion implantation (open access)

Photosensitivity enhancement of PLZT ceramics by positive-ion implantation

The photosensitivity of lead lanthanum zirconate titanate (PLZT) ceramic material used in high resolution, high contrast, and nonvolatile photoferroelectric image storage and display devices is enhanced significantly by positive ion implantation of the PLZT near its surface. Implanted ions include H/sup +/, He/sup +/, Ne/sup +/, Ar/sup +/, as well as chemically reactive ions from Fe, Cr, and Al. The positive ion implantation advantageously serves to shift the absorption characteristics of the PLZT material from near-uv light to visible light. As a result, photosensitivity enhancement is such that the positive ion implanted PLZT plate is sensitive even to sunlight and conventional room lighting, such as fluorescent and incandescent light sources. The method disclosed includes exposing the PLZT plate to the positive ions at sufficient density, from 1 x 10/sup 12/ to 1 x 10/sup 17/, and with sufficient energy, from 100 to 500 keV, to provide photosensitivity enhancement. The PLZT material may have a lanthanum content ranging from 5 to 10%, a lead zirconate content of 62 to 70 mole %, and a lead titanate content of 38 to 30%. The ions are implanted at a depth of 0.1 to 2 microns below the surface of the PLZT plate.
Date: January 28, 1982
Creator: Peercy, P.S. & Land, C.E.
System: The UNT Digital Library
Continuous production of ethanol by use of flocculent Zymomonas mobilis (open access)

Continuous production of ethanol by use of flocculent Zymomonas mobilis

Improved means and process for producing ethanol by fermentation are provided. Another object of the invention is to produce ethanol in a continuous-flow process by means of a biological catalyst that can be retained in a continuous-flow reactor vessel without being bonded to or held within a support material. An additional object of the invention is to provide a fermentation reactor vessel wherein disturbance of the desirable plug flow of sugar solution is minimized. These objects are attained by the preferred apparatus and process of the invention which utilize a newly-discovered flocculent strain of Zymomonas mobilis for converting sugar to ethanol in a continuous flow-type reactor vessel. The flow rate of a sugar-containing solution through a column containing the floc-forming strain of Z. mobilis is adjusted so that a sufficient conversion of sugar to ethanol is achieved in the column and the flocculent Z. mobilis is not washed away in effluent from the column. Carbon dioxide gas generated by the fermentation process is vented from a plurality of points spaced along an inclined column in which the process is conducted, thus minimizing disturbance of the plug flow of liquid by this gas.
Date: January 28, 1982
Creator: Arcuri, E. J. & Donaldson, T. L.
System: The UNT Digital Library
Cathode-preparation method for molten-carbonate fuel cell (open access)

Cathode-preparation method for molten-carbonate fuel cell

A method of preparing a porous cathode structure for use in a molten carbonate fuel cell begins by providing a porous integral plaque of sintered nickel oxide particles. The nickel oxide plaque can be obtained by oxidizing a sintered plaque of nickel metal or by compacting and sintering finely divided nickel oxide particles to the desired pore structure. The porous sintered nickel oxide plaque is contacted with a lithium salt for a sufficient time to lithiate the nickel oxide structure and thus enhance its electronic conductivity. The lithiation can be carried out either within an operating fuel cell or prior to assembling the plaque as a cathode within the fuel cell.
Date: January 28, 1982
Creator: Smith, James L.; Sim, James W. & Kucera, Eugenia H.
System: The UNT Digital Library
Multifrequency, single-pass free-electron laser. [Patent application] (open access)

Multifrequency, single-pass free-electron laser. [Patent application]

A method for simultaneous amplification of laser beams with a sequence of freqeuncies in a single pass, using a relativistic beam of electrons grouped in a sequence of energies corresponding to the sequence of laser beam frequencies is described. The method allows electrons to pass from one potential well or bucket to another adjacent bucket, thus increasing efficiency of trapping and energy conversion.
Date: January 26, 1982
Creator: Szoke, A. & Prosnitz, D.
System: The UNT Digital Library
Doped semiconductor material and method for doping same (open access)

Doped semiconductor material and method for doping same

A method for doping semiconductor material and the semiconductor produced by the method are described. An interface is established between a solid electrolyte and a semiconductor to be doped. The electrolyte is chosen to be an ionic conductor of the selected impurity and the semiconductor material and electrolyte are jointly chosen so that any compound formed from the impurity and the semiconductor will have a free energy no lower than the electrolyte. A potential is then established across the interface so as to allow the impurity ions to diffuse into the semiconductor. In one embodiment the semiconductor and electrolyte may be heated so as to increase the diffusion coefficient.
Date: January 26, 1982
Creator: Yang, C.Y.
System: The UNT Digital Library
Shutdown system for a nuclear reactor (open access)

Shutdown system for a nuclear reactor

An ultimate shutdown system is provided for termination of neutronic activity in a nuclear reactor. The shutdown system includes bead chains comprising spherical containers suspended on a flexible cable. The containers are comprised of mating hemispherical shells which provide a ruggedized enclosure for reactor poison material. The bead chains, normally suspended above the reactor core on storage spools, are released for downward travel upon command from an external reactor monitor. The chains are capable of horizontal movement, so as to flow around obstructions in the reactor during their downward motion.
Date: January 20, 1982
Creator: Groh, E.F.; Olson, A.P.; Wade, D.C. & Robinson, B.W.
System: The UNT Digital Library
Spark-Gap Device for Precise Switching (open access)

Spark-Gap Device for Precise Switching

An improved spark gap apparatus is provided for precise switching of high currents from charged capacitors, and for protecting circuitry and circuit components, such as an energy storage capacitor, from overvoltage surges. The invention includes a pair of niobium electrodes with a melting point greater than 2000/sup 0/C that forms the spark gap. The electrodes are supported by conductive caps spaced apart from one another by an insulating member all of which form a hermetically sealed chamber filled with an inert, ionizable gas, preferably pure xenon. The spark gap device includes a quantity of solid radioactive stabilizer, carbon-14, placed within the hermetically sealed chamber adjacent to the spark gap. Methods for fabricating the device and its components are described. It is claimed that use of the Nb electrodes forestalls electrode erosion even under severe voltage and discharge conditions, that, by employing pure Xe gas, and solid carbon-14 radiation stabilizer, it is unnecessary to employ radioactive gases or chemically plated radioactive sources to promote ionization, and that, by selection of a suitable spark gap, a spark gap device is obtained which is capable of switching at 1700 V +- 10% for input voltage rates up to 570 V/ms and allowing peak …
Date: January 28, 1982
Creator: Boettcher, Gordon E.
System: The UNT Digital Library