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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: December 31, 1990
Creator: Srivastava, Prem C. & Hasan, Ahmad
System: The UNT Digital Library
Precision wire feeder for small diameter wire (open access)

Precision wire feeder for small diameter wire

This invention is comprised of a device for feeding small diameter wire having a diameter less than .04 mm (16 mil) to a welding station which includes a driving wheel for controllably applying a non-deforming driving force to the wire to move the free end of the wire towards the welding station; and a tension device such as a torque motor for constantly applying a reverse force to the wire in opposition to the driving force to keep the wire taut. 1 fig.
Date: December 31, 1990
Creator: Brandon, E. D.; Hooper, F. M. & Reichenbach, M. L.
System: The UNT Digital Library
A backscattering spectrometry device for identifying unknown elements present in a workpiece (open access)

A backscattering spectrometry device for identifying unknown elements present in a workpiece

This invention is comprised of a backscattering spectrometry method and device for identifying and quantifying impurities in a workpiece during processing and manufacturing of that workpiece. While the workpiece is implanted with an ion beam, that same ion beam backscatters resulting from collisions with known atoms and with impurities within the workpiece. Those ions backscatter along a predetermined scattering angle and are filtered using a self-supporting filter to stop the ions with a lower energy because they collided with the known atoms of the workpiece of a smaller mass. Those ions which pass through the filter have a greater energy resulting from impact with impurities having a greater mass than the known atoms of the workpiece. A detector counts the number and measures the energy of the ions which pass through the filter. From the energy determination and knowledge of the scattering angle, a mass calculation determines the identity, and from the number and solid angle of the scattering angle, a relative concentration of the impurity is obtained.
Date: December 31, 1990
Creator: Doyle, Barney L. & Knapp, James A.
System: The UNT Digital Library
Separation of metal ions from aqueous solutions (open access)

Separation of metal ions from aqueous solutions

This invention is comprised of a process and apparatus for quantitatively and selectively separating metal ions from mixtures thereof in aqueous solution. The apparatus includes, in combination, a horizontal electrochemical flowing cell containing flowing bulk electrolyte solution and an aqueous, metal ion-containing solution, the cell containing a metal mesh working electrode, a counter electrode positioned downstream from the working electrode, an independent variable power supply/potentiostat positioned outside of the flowing cell and connected to the electrodes, and optionally a detector such as a chromatographic detector, positioned outside the flowing cell. This apparatus and its operation has significant application where trace amounts of metal ions are to be separated.
Date: December 31, 1991
Creator: Almon, A.
System: The UNT Digital Library
Noise reduction in negative-ion quadrupole mass spectrometry (open access)

Noise reduction in negative-ion quadrupole mass spectrometry

This invention is comprised of a quadrupole mass spectrometer (QMS) system having an ion source, quadrupole mass filter, and ion collector/recorder system. A weak, transverse magnetic field and an electron collector are disposed between the quadrupole and ion collector. When operated in negative ion mode, the ion source produces a beam of primarily negatively-charged particles from a sample, including electrons as well as ions. The beam passes through the quadrupole and enters the magnetic field, where the electrons are deflected away from the beam path to the electron collector. The negative ions pass undeflected to the ion collector where they are detected and recorded as a mass spectrum.
Date: December 31, 1991
Creator: Chastagner, P.
System: The UNT Digital Library
Robot arm apparatus (open access)

Robot arm apparatus

A robot arm apparatus is provided for inspecting and/or maintaining an interior of a steam generator which has an outside wall and a port for accessing the interior of the steam generator. The robot arm apparatus includes a flexible movable conduit for conveying inspection and/or maintenance apparatus from outside the steam generator to the interior of the steam generator. The flexible conduit has a terminal working end which is translated into and around the interior of the steam generator. Three motors located outside the steam generator are employed for moving the terminal working end inside the steam generator in ``x,`` ``y,`` and ``z`` directions, respectively. Commonly conducted inspection and maintenance operations include visual inspection for damaged areas, water jet lancing for cleaning sludge deposits, core boring for obtaining sludge deposits, and scrubbing of internal parts.
Date: December 31, 1990
Creator: Nachbar, H. D.
System: The UNT Digital Library
Method of recovering hazardous waste from phenolic resin filters (open access)

Method of recovering hazardous waste from phenolic resin filters

A method has been found for treating phenolic resin filter, whereby the filter is solubilized within the filter cartridge housing so the filter material can be removed from the cartridge housing in a remote manner. The invention consists of contacting the filter within the housing with an aqueous solution of about 8 to 12M nitric acid, at a temperature from about 110 to 190{degree}F, maintaining the contact for a period of time sufficient to solubilize the phenolic material within the housing, and removing the solubilized phenolic material from the housing, thereby removing the filter cartridge from the housing. Any hazardous or other waste material can then be separated from the filter material by chemical or other means.
Date: December 31, 1990
Creator: Meikrantz, David H.; Bourne, Gary L.; McFee, John N.; Burdge, Bradley G. & McConnell, John W., Jr.
System: The UNT Digital Library
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
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
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
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
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
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: December 31, 1991
Creator: Smith, James L. & Kucera, Eeugenia H.
System: The UNT Digital Library
Portable high precision pressure transducer system (open access)

Portable high precision pressure transducer system

A high precision pressure transducer system for checking the reliability of a second pressure transducer system used to monitor the level of a fluid confined in a holding tank. Since the response of the pressure transducer is temperature sensitive, it is continually housed in an battery powered oven which is configured to provide a temperature stable environment at specified temperature for an extended period of time. Further, a high precision temperature stabilized oscillator and counter are coupled to a single board computer to accurately determine the pressure transducer oscillation frequency and convert it to an applied pressure. All of the components are powered by the batteries which during periods of availability of line power are charged by an on board battery charger. The pressure readings outputs are transmitted to a line printer and a vacuum florescent display.
Date: December 31, 1992
Creator: Piper, T. C.; Morgan, J. P.; Marchant, N. J. & Bolton, S. M.
System: The UNT Digital Library