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Process for the recovery of strontium from acid solutions (open access)

Process for the recovery of strontium from acid solutions

The invention is a process for selectively extracting strontium and technetium values from aqueous nitric acid waste solutions containing these and other fission product values. The extractant is a macrocyclic polyether in a diluent which is insoluble in water, but which will itself dissolve a small amount of water. The process will extract strontium and technetium values from nitric acid solutions which are up to 6 molar in nitric acid.
Date: December 31, 1990
Creator: Horwitz, E. P. & Dietz, M. L.
System: The UNT Digital Library
Methods of and apparatus for recording images occurring just prior to a rapid, random event (open access)

Methods of and apparatus for recording images occurring just prior to a rapid, random event

An apparatus and a method are disclosed for recording images of events in a medium wherein the images that are recorded are of conditions existing just prior to and during the occurrence of an event that triggers recording of these images. The apparatus and method use an optical delay path that employs a spherical focusing mirror facing a circular array of flat return mirrors around a central flat mirror. The image is reflected in a symmetric pattern which balances astigmatism which is created by the spherical mirror. Delays on the order of hundreds of nanoseconds are possible.
Date: December 31, 1991
Creator: Kelley, E. F.
System: The UNT Digital Library
Ultrasonic cleaning of interior surface (open access)

Ultrasonic cleaning of interior surface

This invention is comprised of an ultrasonic cleaning apparatus for cleaning the interior surfaces of tubes. The apparatus includes an ultrasonic generator and reflector each coupled to opposing ends of the open-ended, fluid-filled tube. Fluid-tight couplings seal the reflector and generator to the tube, preventing leakage of fluid from the interior of the tube. The reflector and generator are operatively connected to actuators, whereby the distance between them can be varied. When the distance is changed, the frequency of the sound waves is simultaneously adjusted to maintain the resonant frequency of the tube so that a standing wave is formed in the tube, the nodes of which are moved axially to cause cavitation along the length of the tube. Cavitation maximizes mechanical disruption and agitation of the fluid, dislodging foreign material from the interior surface.
Date: December 31, 1991
Creator: Odell, D. M.
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: December 31, 1990
Creator: Tsai, TenLin; Sanville, C. Y.; Coleman, R. D. & Schertz, W. W.
System: The UNT Digital Library
Explosive laser light initiation of propellants (open access)

Explosive laser light initiation of propellants

This invention is comprised of an improved initiator for artillery shell using an explosively generated laser light to uniformly initiate the propellent. A small quantity of a high explosive, when detonated, creates a high pressure and temperature, causing the surrounding noble gas to fluoresce. This fluorescence is directed into a lasing material, which lases, and directs laser light into a cavity in the propellant, uniformly initiating the propellant.
Date: December 31, 1992
Creator: Piltch, M. S.
System: The UNT Digital Library
Selectable fragmentation warhead (open access)

Selectable fragmentation warhead

This report discusses a selectable fragmentation warhead which is capable of producing a predetermined number of fragments from a metal plate, and accelerating the fragments toward a target. A first explosive located adjacent to the plate is detonated at selected number of points by laser-driven slapper detonators. In one embodiment, a smoother-disk and a second explosive, located adjacent to the first explosive, serve to increase acceleration of the fragments toward a target. The ability to produce a selected number of fragments allows for effective destruction of a chosen target.
Date: December 31, 1992
Creator: Bryan, C. S.; Paisley, D. L.; Montoya, N. I. & Stahl, D. B.
System: The UNT Digital Library
Cobalt carbonyl catalyzed olefin hydroformylation in supercritical carbon dioxide (open access)

Cobalt carbonyl catalyzed olefin hydroformylation in supercritical carbon dioxide

A method of olefin hydroformylation is provided wherein an olefin reacts with a carbonyl catalyst and with reaction gases such as hydrogen and carbon monoxide in the presence of a supercritical reaction solvent, such as carbon dioxide. The invention provides higher yields of n-isomer product without the gas-liquid mixing rate limitation seen in conventional Oxo processes using liquid media.
Date: December 31, 1992
Creator: Rathke, Jerome W. & Klingler, Robert J.
System: The UNT Digital Library
Process and apparatus for coal hydrogenation (open access)

Process and apparatus for coal hydrogenation

In a coal liquefaction process an aqueous slurry of coal is prepared containing a dissolved liquefaction catalyst. A small quantity of oil is added to the slurry and then coal-oil agglomerates are prepared by agitation of the slurry at atmospheric pressure. The resulting mixture is drained of excess water and dried at atmospheric pressure leaving catalyst deposited on the agglomerates. The agglomerates then are fed to an extrusion device where they are formed into a continuous ribbon of extrudate and fed into a hydrogenation reactor at elevated pressure and temperature. The catalytic hydrogenation converts the extrudate primarily to liquid hydrocarbons in the reactor. The liquid drained in recovering the agglomerates is recycled. 1 fig.
Date: December 31, 1990
Creator: Ruether, J. A. & Simpson, T. B.
System: The UNT Digital Library
Ballistic impulse gauge (open access)

Ballistic impulse gauge

This invention is comprised of a gauge for detecting the impulse generated in sample materials by X-rays or other impulse producing mechanisms which utilizes a pair of flat annular springs to support a plunger relative to a housing which may itself be supported by a pair of flat annular springs in a second housing. The plunger has a mounting plate mounted on one end and at the other, a position or velocity transducer is mounted. The annular springs consist of an outer ring and an inner ring with at least three arcuate members connecting the outer within the inner ring.
Date: December 31, 1992
Creator: Ault, S. K.
System: The UNT Digital Library
Synthesis of actinide nitrides, phosphides, sulfides and oxides (open access)

Synthesis of actinide nitrides, phosphides, sulfides and oxides

This invention is comprised of a process of preparing an actinide compound of the formula An{sub x}Z{sub y} wherein An is an actinide metal atom selected from the group consisting of thorium, uranium, plutonium, neptunium, and americium, x is selected from the group consisting of one, two or three, Z is a main group element atom selected from the group consisting of nitrogen, phosphorus, oxygen and sulfur and y is selected from the group consisting of one, two, three or four, by admixing an actinide organometallic precursor wherein said actinide is selected from the group consisting of thorium, uranium, plutonium, neptunium, and americium, a suitable solvent and a protic Lewis base selected from the group consisting of ammonia, phosphine, hydrogen sulfide and water, at temperatures and for time sufficient to form an intermediate actinide complex, heating said intermediate actinide complex at temperatures and for time sufficient to form the actinide compound, and a process of depositing a thin film of such an actinide compound, e.g., uranium mononitride, by subliming an actinide organometallic precursor, e.g., a uranium amide precursor, in the presence of an effective amount of a protic Lewis base, e.g., ammonia, within a reactor at temperatures and for time …
Date: April 2, 1991
Creator: Van Der Sluys, W. G.; Burns, C. J. & Smith, D. C.
System: The UNT Digital Library
Photovoltaic solar concentrator module (open access)

Photovoltaic solar concentrator module

This invention consists of a planar photovoltaic concentrator module for producing an electrical signal from incident solar radiation which includes an electrically insulating housing having a front wall, an opposing back wall and a hollow interior. A solar cell having electrical terminals is positioned within the interior of the housing. A planar conductor is connected with a terminal of the solar cell of the same polarity. A lens forming the front wall of the housing is operable to direct solar radiation incident to the lens into the interior of the housing. A refractive optical element in contact with the solar cell and facing the lens receives the solar radiation directed into the interior of the housing by the lens and directs the solar radiation to the solar cell to cause the solar cell to generate an electrical signal. An electrically conductive planar member is positioned in the housing to rest on the housing back wall in supporting relation with the solar cell terminal of opposite polarity. The planar member is operable to dissipate heat radiated by the solar cell as the solar cell generates an electrical signal and further forms a solar cell conductor connected with the solar cell terminal …
Date: May 16, 1991
Creator: Chiang, C. J.
System: The UNT Digital Library
Virtually distortion-free imaging system for large field, high resolution lithography using electrons, ions or other particle beams (open access)

Virtually distortion-free imaging system for large field, high resolution lithography using electrons, ions or other particle beams

Virtually distortion free large field high resolution imaging is performed using an imaging system which contains large field distortion or field curvature. A reticle is imaged in one direction through the optical system to form an encoded mask. The encoded mask is then imaged back through the imaging system onto a wafer positioned at the reticle position. Particle beams, including electrons, ions and neutral particles, may be used as well as electromagnetic radiation.
Date: April 10, 1991
Creator: Hawryluk, A. M. & Ceglio, N. M.
System: The UNT Digital Library
Improved monolithic tandem solar cell (open access)

Improved monolithic tandem solar cell

A single-crystal, monolithic, tandem, photovoltaic solar cell is described which includes (a) an InP substrate having upper and lower surfaces, (b) a first photoactive subcell on the upper surf ace of the InP substrate, (c) a second photoactive subcell on the first subcell; and (d) an optically transparent prismatic cover layer over the second subcell. The first photoactive subcell is GaInAsP of defined composition. The second subcell is InP. The two subcells are lattice matched.
Date: April 23, 1991
Creator: Wanlass, M. W.
System: The UNT Digital Library
Method and apparatus for removing ions from soil (open access)

Method and apparatus for removing ions from soil

This invention is comprised of a method and apparatus for selectively removing species of ions from an area of soil. Permeable membranes and impregnated with an ion exchange resin that is specific to one or more species of chemical ions are inserted into ground in close proximity to, and on opposing sides of, a soil area of interest. An electric potential is applied across electrodes and to cause the migration of ions out of soil area toward the membranes. Preferably, the resin exchanges ions of sodium or hydrogen for ions of mercury that it captures from soil area. Once membranes and become substantially saturated with mercury ions, the potential applied across electrodes and is discontinued and membranes and are preferably removed from soil for storage or recovery of the ions. The membranes are also preferably impregnated with a buffer to inhibit the effect of the hydrolysis of water by current from the electrodes.
Date: December 31, 1992
Creator: Bibler, J. P.
System: The UNT Digital Library
Oil/gas collector/separator for underwater oil leaks (open access)

Oil/gas collector/separator for underwater oil leaks

This invention is comprised of an oil/gas collector/separator for recovery of oil leaking, for example, from an offshore or underwater oil well. The separator is floated over the point of the leak and tethered in place so as to receive oil/gas floating, or forced under pressure, toward the water surface from either a broken or leaking oil well casing, line, or sunken ship. The separator is provided with a downwardly extending skirt to contain the oil/gas which floats or is forced upward into a dome wherein the gas is separated from the oil/water, with the gas being flared (burned) at the top of the dome, and the oil is separated from water and pumped to a point of use. Since the density of oil is less than that of water it can be easily separated from any water entering the dome.
Date: December 31, 1992
Creator: Henning, C. D.
System: The UNT Digital Library
Multiple-frequency acoustic wave devices for chemical sensing and materials characterization in both gas and liquid phase (open access)

Multiple-frequency acoustic wave devices for chemical sensing and materials characterization in both gas and liquid phase

This invention consists of a chemical sensor that includes two or more pairs of interdigital electrodes having different periodicities. Each pair is comprised of a first electrode and a second electrode. The electrodes are patterned on a surface of a piezoelectric substrate. Each pair of electrodes may launch and receive various acoustic waves (AW), including a surface acoustic wave (SAW), and may also launch and receive several acoustic plate modes (APMs). The frequencies associated with each are functions of the transducer periodicity as well as the velocity of the particular AW in the chosen substrate material. An AW interaction region exists between each pair of electrodes. Circuitry is used to launch, receive, and monitor the propagation characteristics of the AWs and may be configured in an intermittent measurement fashion or in a continuous measurement fashion. Perturbations to the AW velocity and attenuation are recorded at several frequencies and provide the sensor response.
Date: December 31, 1991
Creator: Martin, S. J. & Ricco, A. J.
System: The UNT Digital Library
Dual output acoustic wave sensor for molecular identification (open access)

Dual output acoustic wave sensor for molecular identification

The invention comprises a method for the identification and quantification of sorbed chemical species onto a coating of a device capable of generating and receiving an acoustic wave, by measuring the changes in the velocity of the acoustic wave resulting from the sorption of the chemical species into the coating as the wave travels through the coating and by measuring the changes in the attenuation of an acoustic wave resulting from the sorption of the chemical species into the coating as the wave travels through the coating. The inventive method further correlates the magnitudes of the changes of velocity with respect to changes of the attenuation of the acoustic wave to identify the sorbed chemical species. The absolute magnitudes of the velocity changes or the absolute magnitude of the attenuation changes are used to determine the concentration of the identified chemical species.
Date: October 3, 1990
Creator: Frye, G. C. & Martin, S. J.
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 for dissolution and stabilization of silica-rich fibers (open access)

Method for dissolution and stabilization of silica-rich fibers

This invention is comprised of a method for dissolving silica-rich fibers such as borosilicate fibers, fiberglass and asbestos to stabilize them for disposal. The method comprises (1) immersing the fibers in hot, five-weight-percent sodium hydroxide solution until the concentration of dissolved silica reaches equilibrium and a only a residue is left (about 48 hours), then immersing the residue in hot, five-weight-percent nitric acid until the residue dissolves (about 96 hours). After adjusting the pH of the dissolved fibers to be caustic, the solution can then be added to a waste vitrification stream for safe disposal. The method is useful in disposing contaminated HEME and HEPA filters.
Date: December 31, 1992
Creator: Jantzen, Carol M.
System: The UNT Digital Library
Polishing compound for plastic surfaces (open access)

Polishing compound for plastic surfaces

This invention is comprised of a polishing compound for plastic materials. The compound includes approximately by approximately by weight 25 to 80 parts at least one petroleum distillate lubricant, 1 to 12 parts mineral spirits, 50 to 155 parts abrasive paste, and 15 to 60 parts water. Preferably, the compound includes approximately 37 to 42 parts at least one petroleum distillate lubricant, up to 8 parts mineral spirits, 95 to 110 parts abrasive paste, and 50 to 55 parts water. The proportions of the ingredients are varied in accordance with the particular application. The compound is used on PLEXIGLAS{trademark}, LEXAN{trademark}, LUCITE{trademark}, polyvinyl chloride (PVC), and similar plastic materials whenever a smooth, clear polished surface is desired.
Date: January 1, 1991
Creator: Stowell, M. S.
System: The UNT Digital Library
Eliminating livelock in flushable routing networks (open access)

Eliminating livelock in flushable routing networks

This invention is comprised of a method for livelock-free message routing is provided in a network of interconnected nodes that is flushable in time T. An input message processor generates sequences of at least N time intervals, each of duration T. An input register provides for receiving and holding each input message, where the message is assigned a priority state p during an nth one of the N time intervals. At each of the network nodes a message processor reads the assigned priority state and awards priority to messages with priority state (p-1) during an nth time interval and to messages with priority state p during an (n + 1)th time interval. The messages that are awarded priority are output on an output path toward the addressed output message processor. Thus, no message remains in the network for a time longer than T.
Date: December 31, 1992
Creator: Faber, V.
System: The UNT Digital Library
False color viewing device (open access)

False color viewing device

This invention consists of a viewing device for observing objects in near-infrared false-color comprising a pair of goggles with one or more filters in the apertures, and pads that engage the face for blocking stray light from the sides so that all light reaching, the user`s eyes come through the filters. The filters attenuate most visible light and pass near-infrared (having wavelengths longer than approximately 700 nm) and a small amount of blue-green and blue-violet (having wavelengths in the 500 to 520 nm and shorter than 435 nm, respectively). The goggles are useful for looking at vegetation to identify different species and for determining the health of the vegetation, and to detect some forms of camouflage.
Date: May 8, 1991
Creator: Kronberg, J. W.
System: The UNT Digital Library
Apparatus and method for removing particulate deposits from high temperature filters (open access)

Apparatus and method for removing particulate deposits from high temperature filters

The combustion of a fuel-air mixture is used to provide a high-temperature and high-pressure pulse of gaseous combustion products for the back-flush cleaning of ceramic filter elements contained in a barrier filter system and utilized to separate particulates from particulate-laden process gases at high temperature and high pressure. The volume of gaseous combustion products provided by the combustion of the fuel-air mixture is preferably divided into a plurality of streams each passing through a sonic orifice and conveyed to the open end of each filter element as a high pressure pulse which passes through the filter elements and dislodges dust cake supported on a surface of the filter element.
Date: December 31, 1992
Creator: Nakaishi, C. V.; Holcombe, N. T. & Micheli, P. L.
System: The UNT Digital Library
Chloromethyl chlorosulfate as a voltage delay inhibitor in lithium cells (open access)

Chloromethyl chlorosulfate as a voltage delay inhibitor in lithium cells

Chloromethyl chlorosulfate (CMCS) is used as a passive film growth inhibitor in electrochemical cells to minimize voltage delay and low-voltage discharge. Film growth on lithium anodes is significantly diminished when CMCS is added to SOCl{sub 2} and SO{sub 2}Cl{sub 2} electrolytes of lithium batteries. The CMCS also has the effect of extending the shelf-life of Li/SOCl{sub 2} and Li/SO{sub 2}Cl{sub 2} batteries.
Date: April 5, 1991
Creator: Delnick, F. M.
System: The UNT Digital Library