362 Matching Results

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Preparation of high specific activity technetium-96 (open access)

Preparation of high specific activity technetium-96

The present invention relates to a method of producing Tc-96 from the proton irradiation of a rhodium target and a technique for isolating under remote hot cell conditions the Tc-96 from the proton irradiated target.
Date: December 31, 1990
Creator: Mausner, L. F.; Srivastava, S. C. & Prach, T.
System: The UNT Digital Library
Chemical vapor infiltration using microwave energy (open access)

Chemical vapor infiltration using microwave energy

This invention is comprised of a method for producing reinforced ceramic composite articles by means of chemical vapor infiltration and deposition in which an inverted temperature gradient is utilized. Microwave energy is the source of heat for the process.
Date: December 31, 1992
Creator: Devlin, D. J.; Currier, R. P.; Laia, J. R. & Barbero, R. S.
System: The UNT Digital Library
Microwave impregnation of porous materials with thermal energy storage materials (open access)

Microwave impregnation of porous materials with thermal energy storage materials

A method for impregnating a porous, non-metallic construction material with a solid phase-change material is described. The phase-change material in finely divided form is spread onto the surface of the porous material, after which the porous material is exposed to microwave energy for a time sufficient to melt the phase-change material. The melted material is spontaneously absorbed into the pores of the porous material. A sealing chemical may also be included with the phase-change material (or applied subsequent to the phase-change material) to seal the surface of the porous material. Fire retardant chemicals may also be included with the phase-change materials. The treated construction materials are better able to absorb thermal energy and exhibit increased heat storage capacity.
Date: December 31, 1992
Creator: Benson, D. K. & Burrows, R. W.
System: The UNT Digital Library
Digitally controlled distributed phase shifter (open access)

Digitally controlled distributed phase shifter

A digitally controlled distributed phase shifter is comprised of N phase shifters. Digital control is achieved by using N binary length-weighted electrodes located on the top surface of a waveguide. A control terminal is attached to each electrode thereby allowing the application of a control signal. The control signal is either one of two discrete bias voltages. The application of the discrete bias voltages change the modal index of a portion of the waveguide that corresponds to a length of the electrode to which the bias voltage is applied, thereby causing the phase to change through the underlying portion of the waveguide. The digitally controlled distributed phase shift network has a total phase shift comprised of the sum of the individual phase shifters.
Date: December 31, 1992
Creator: Hietala, V. M.; Kravitz, S. H. & Vawter, G. A.
System: The UNT Digital Library
Drill string enclosure (open access)

Drill string enclosure

This invention is comprised of a drill string enclosure which consists of six component parts, including; a top bracket, an upper acrylic cylinder, an acrylic drill casing guide, a lower acrylic cylinder, a bottom bracket, and three flexible ducts. The upper acrylic cylinder is optional based upon the drill string length. The drill string enclosure allows for an efficient drill and sight operation at a hazardous waste site.
Date: December 31, 1992
Creator: Jorgensen, D. K.; Kuhns, D. J.; Wiersholm, O. & Miller, T. A.
System: The UNT Digital Library
Vortex nozzle for segmenting and transporting metal chips from turning operations (open access)

Vortex nozzle for segmenting and transporting metal chips from turning operations

This invention is comprised of an apparatus for collecting, segmenting and conveying metal chips from machining operations which utilizes a compressed gas driven vortex nozzle for receiving the chip and twisting it to cause the chip to segment through the application of torsional forces to the chip. The vortex nozzle is open ended and generally tubular in shape with a converging inlet end, a constant diameter throat section and a diverging exhaust end. Compressed gas is discharged through angled vortex ports in the nozzle throat section to create vortex flow in the nozzle and through an annular inlet at the entrance to the converging inlet end to create suction at the nozzle inlet and cause ambient air to enter the nozzle. The vortex flow in the nozzle causes the metal chip to segment and the segments thus formed to pass out of the discharge end of the nozzle where they are collected, cleaned and compacted as needed.
Date: December 31, 1992
Creator: Bieg, L. F.
System: The UNT Digital Library
Recovery of germanium-68 from irradiated targets (open access)

Recovery of germanium-68 from irradiated targets

This invention is comprised of a process for selective separation of germanium-68 from proton irradiated molybdenum targets is provided and includes dissolving the molybdenum target in a hydrogen peroxide solution to form a first ion-containing solution, contacting the first ion-containing solution with a cationic resin whereby ions selected from the group consisting of molybdenum, niobium, technetium, selenium,vanadium, arsenic, germanium, zirconium and rubidium remain in a second ion-containing solution while ions selected from the group consisting of rubidium, zinc, beryllium, cobalt, iron, manganese, chromium, strontium, yttrium and zirconium are selectively adsorbed by the first resin, adjusting the pH of the second ion-containing solution to within a range of from about 0.7 to about 3.0, adjusting the soluble metal halide concentration in the second ion-containing solution to a level adapted for subsequent separation of germanium, contacting the pH-adjusted, soluble metal halide-containing second ion-containing solution with a dextran-based material whereby germanium ions are separated by the dextran-based material, and recovering the germanium from the dextran-based material, preferably by distillation.
Date: December 31, 1992
Creator: Phillips, D. R.; Jamriska, D. J. Sr. & Hamilton, V. T.
System: The UNT Digital Library
Normalization method for video images (open access)

Normalization method for video images

The present invention relates to a method and apparatus for automatically and adaptively normalizing analog signals representative of video images in object detection systems. Such normalization maximizes the average information content of the video images and, thereby, provides optimal digitized images for object detection and identification. The present invention manipulates two system control signals -- gain control signal and offset control signal -- to convert an analog image signal into a transformed analog image signal, such that the corresponding digitized image contains the maximum amount of information achievable with a conventional object detection system. In some embodiments of the present invention, information content is measured using parameters selected from image entropy, image mean, and image variance.
Date: December 31, 1992
Creator: Donohoe, G. W. & Hush, D. R.
System: The UNT Digital Library
Method for exponentiating in cryptographic systems (open access)

Method for exponentiating in cryptographic systems

An improved cryptographic method utilizing exponentiation is provided which has the advantage of reducing the number of multiplications required to determine the legitimacy of a message or user. The basic method comprises the steps of selecting a key from a pre-approved group of integer keys g; exponentiating the key by an integer value e, where e represents a digital signature, to generate a value g{sup e}; transmitting the value g{sup e} to a remote facility by a communications network; receiving the value g{sup e} at the remote facility; and verifying the digital signature as originating from the legitimate user. The exponentiating step comprises the steps of initializing a plurality of memory locations with a plurality of values g{sup xi}, computing a{sub i} representations for a integer base b, where a{sub i} represents the weighing factor of the ith digit of the integer e; computing the individual values of c{sub d} according to the rule: c{sub d}={product}a{sub i}=d g{sup x {sub i}}; and computing the product of {product}{sup h}/{sub d=1} c{sub d}{sup d} from the stored values of from the plurality of memory locations so as to determine a value for g{sup e}.
Date: December 31, 1992
Creator: Brickell, E. F.; Gordon, D. M. & McCurley, K. S.
System: The UNT Digital Library
Filtered cathodic arc source (open access)

Filtered cathodic arc source

Disclosed is a continuous, cathodic arc ion source coupled to a macro-particle filter capable of separation or elimination of macro-particles from the ion flux produced by cathodic arc discharge. The ion source employs an axial magnetic field on a cathode (target) having tapered sides to confine the arc, thereby providing high target material utilization. A bent magnetic field is used to guide the metal ions from the target to the part to be coated. The macro-particle filter consists of two straight solenoids, end to end, but placed at 45{degrees} to one another, which prevents line-of-sight from the arc spot on the target to the parts to be coated, yet provides a path for ions and electrons to flow, and includes a series of baffles for trapping the macro-particles.
Date: December 31, 1992
Creator: Falabella, S. & Sanders, D. M.
System: The UNT Digital Library
Fail-safe storage rack for fuel rod assemblies (open access)

Fail-safe storage rack for fuel rod assemblies

This report discusses a fail-safe storage rack which is provided for interim storage of spent but radioactive nuclear fuel rod assemblies. The rack consists of a checkerboard array of substantially square, elongate receiving tubes fully enclosed by a double walled container, the outer wall of which is imperforate for liquid containment and the inner wall of which is provided with perforations for admitting moderator liquid flow to the elongate receiving tubes, the liquid serving to take up waste heat from the stored nuclear assemblies and dissipate same to the ambient liquid reservoir. A perforated cover sealing the rack facilitates cooling liquid entry and dissipation.
Date: December 31, 1991
Creator: Lewis, D. R.
System: The UNT Digital Library
Method and apparatus for determining two-phase flow in rock fracture (open access)

Method and apparatus for determining two-phase flow in rock fracture

One object of the present invention to provide an improved method and apparatus for measuring the relative permeability of a rock fracture to multiple phases in a manner which will provide even more uniform delivery of both wetting and non-wetting phases to the fracture edge. It is another object of the invention to provide an improved method and apparatus for measuring the permeability of multiple phases through a rock fracture which comprises delivering the respective phases through manifold means to uniformly deliver the respective phases to and from opposite edges of the rock fracture in a distributed manner across the gap of the fracture wherein the manifold means for delivering the wetting phase comprises porous block means having a side facing the rock fracture edge and bore means therein for providing uniform distribution of the wetting phase to the porous block surfaces, and the manifold means for delivering the non-wetting phase include a plenum in communication with parallel grooves disposed on a surface of the porous means facing perpendicular to the rock fracture edge. These and other objects of the invention will be apparent from the following description and accompanying drawings.
Date: December 31, 1992
Creator: Persoff, P.; Pruess, K. & Myer, L.
System: The UNT Digital Library
Method and apparatus for transporting liquid slurries (open access)

Method and apparatus for transporting liquid slurries

An improved method and device to prevent erosion of slurry transport devices is disclosed which uses liquid injection to prevent contact by the slurry composition with the inner surface of the walls of the transport system. A non-abrasive liquid is injected into the slurry transport system and maintains intimate contact with the entire inner surface of the transport system, thereby creating a fluid barrier between the nonabrasive liquid and the inner surface of the transport system which thereby prevents erosion.
Date: December 31, 1991
Creator: Berry, G. F.; Lyczkowski, R. W. & Wang, Chi-Sheng
System: The UNT Digital Library
Traveling-wave photodetector (open access)

Traveling-wave photodetector

The traveling-wave photodetector of the present invention combines an absorptive optical waveguide and an electrical transmission line, in which optical absorption in the waveguide results in a photocurrent at the electrodes of the electrical transmission line. The optical waveguide and electrical transmission line of the electrically distributed traveling-wave photodetector are designed to achieve matched velocities between the light in the optical waveguide and electrical signal generated on the transmission line. This velocity synchronization provides the traveling-wave photodetector with a large electrical bandwidth and a high quantum efficiency, because of the effective extended volume for optical absorption. The traveling-wave photodetector also provides large power dissipation, because of its large physical size.
Date: December 31, 1992
Creator: Hietala, V. M. & Vawter, G. A.
System: The UNT Digital Library
System to control contamination during retrieval of buried TRU waste (open access)

System to control contamination during retrieval of buried TRU waste

Between 1950 and 1970 the Department of Energy`s Rocky Flats Plant generated transuranic (TRU) contaminated waste, which was buried at the Idaho National Engineering Laboratory. This waste must now be retrieved and sent to a permanent disposal site. During retrieval the main contaminates to be controlled are compounds of plutonium and americium. Since these substances are small sized, and extremely mobile, airborne concentrations must be kept to a minimum to effectively eliminate personnel uptake during retrieval operations. This report describes an invention that relates to a system to control contamination due to TRU airborne particles and was developed consisting of an outer containment building, an inner containment area, a dust suppression system including an electrostatic contaminate capture subsystem, a contamination control system including a moisture control subsystem, a rapid monitoring subsystem, and a lifting and moving system including recovery and repackaging subsystems, and a lifting and moving system including recovery and repackaging subsystems.
Date: December 31, 1991
Creator: Menkhaus, D. E.; Loomis, G. G.; Feldman, E. M.; Scott, D. W.; Mullen, C. K. & Meyer, L. C.
System: The UNT Digital Library
X-ray tomographic image magnification process, system and apparatus therefor (open access)

X-ray tomographic image magnification process, system and apparatus therefor

A computerized three-dimensional x-ray tomographic microscopy system is disclosed, comprising: (a) source means for providing a source of parallel x-ray beams; (b) staging means for staging and sequentially rotating a sample to be positioned in the path of the beams; (c) x-ray image magnifier means positioned in the path of the beams downstream from the sample; (d) detecting means for detecting the beams after being passed through and magnified by the image magnifier means; and (e) computing means for analyzing values received from the detecting means, and converting the values into three-dimensional representations. Also disclosed is a process for magnifying an x-ray image, and apparatus therefor.
Date: December 31, 1991
Creator: Kinney, J. H.; Bonse, U. K.; Johnson, Q. C.; Nichols, M. C.; Saroyan, R. A.; Massey, W. N. et al.
System: The UNT Digital Library
Phase-sensitive flow cytometer (open access)

Phase-sensitive flow cytometer

This report describes phase-sensitive flow cytometer (FCM) which provides additional FCM capability to use the fluorescence lifetime of one or more fluorochromes bound to single cells to provide additional information regarding the cells. The resulting fluorescence emission can be resolved into individual fluorescence signals if two fluorochromes are present or can be converted directly to a decay lifetime from a single fluorochrome. The excitation light for the fluorochromes is modulated to produce an amplitude modulated fluorescence pulse as the fluorochrome is excited in the FCM. The modulation signal also forms a reference signal that is phase-shifted a selected amount for subsequent mixing with the output modulated fluorescence intensity signal in phase-sensitive detection circuitry. The output from the phase-sensitive circuitry is then an individual resolved fluorochrome signal or a single fluorochrome decay lifetime, depending on the applied phase shifts.
Date: December 31, 1992
Creator: Steinkamp, J. A.
System: The UNT Digital Library
Separation of Metals by Supported Liquid Membranes (open access)

Separation of Metals by Supported Liquid Membranes

A supported liquid membrane system for the separation of a preselected chemical species within a feedstream, preferably an aqueous feedstream, includes a feed compartment containing a feed solution having at least one preselected chemical species therein, a stripping compartment containing a stripping solution therein, and a microporous polybenzimidazole membrane situated between the compartments, the microporous polybenzimidazole membrane containing an extractant mixture selective for the preselected chemical species within the membrane pores is disclosed along with a method of separating preselected chemical species from a feedstream with such a system, and a supported liquid membrane for use in such a system.
Date: December 31, 1990
Creator: Takigawa, Doreen Y.
System: The UNT Digital Library
Inflatable containment diaphragm for sealing and removing stacks (open access)

Inflatable containment diaphragm for sealing and removing stacks

A diaphragm with an inflatable torus-shaped perimeter is used to seal at least one end of a stack so that debris that might be hazardous will not be released during removal of the stack. A diaphragm is inserted and inflated in the lower portion of a stack just above where the stack is to be cut such that the perimeter of the diaphragm expands and forms a seal against the interior surface of the stack.
Date: December 31, 1991
Creator: Meskanick, G. R. & Rosso, D. T.
System: The UNT Digital Library
Enhanced radiation resistant fiber optics (open access)

Enhanced radiation resistant fiber optics

A process for producing an optical fiber having enhanced radiation resitance is provided, the process including maintaining an optical fiber within a hydrogen-containing atmosphere for sufficient time to yield a hydrogen-permeated optical fiber having an elevated internal hydrogen concentration, and irradiating the hydrogen-permeated optical fiber at a time while the optical fiber has an elevated internal hydrogen concentration with a source of ionizing radiation. The radiation source is typically a cobalt-60 source and the fiber is pre-irradiated with a dose level up to about 1000 kilorads of radiation.
Date: December 31, 1992
Creator: Lyons, P. B. & Looney, L. D.
System: The UNT Digital Library
Cesium iodide alloys (open access)

Cesium iodide alloys

This invention relates to a CsI composition with improved mechanical strength and outstanding multispectral infrared transmittance, for window use. The additive is a monovalent iodide, other than CsI, added in amounts sufficient to maximize fracture strength from 16 to 40 MPa, while maintaining at least 10% transparency in the 4 to 50 micrometer wavelength range. The preferred additive is AgI, although RbI or CuI can be used. 6 figs. (DLC)
Date: December 31, 1991
Creator: Kim, Hyoun-Ee & Moorhead, A. J.
System: The UNT Digital Library
Sensors for Monitoring Waste Glass Quality (open access)

Sensors for Monitoring Waste Glass Quality

None
Date: December 31, 1992
Creator: Bickford, Dennis F.
System: The UNT Digital Library
High brightness electron accelerator (open access)

High brightness electron accelerator

A compact high brightness linear accelerator is provided for use, e.g., in a free electron laser. The accelerator has a first plurality of acclerating cavities having end walls with four coupling slots for accelerating electrons to high velocities in the absence of quadrupole fields. A second plurality of cavities receives the high velocity electrons for further acceleration, where each of the second cavities has end walls with two coupling slots for acceleration in the absence of dipole fields. The accelerator also includes a first cavity with an extended length to provide for phase matching the electron beam along the accelerating cavities. A solenoid is provided about the photocathode that emits the electrons, where the solenoid is configured to provide a substantially uniform magnetic field over the photocathode surface to minimize emittance of the electrons as the electrons enter the first cavity.
Date: December 31, 1992
Creator: Sheffield, R. L.; Carlsten, B. E. & Young, L. M.
System: The UNT Digital Library
Method for Improving the Growth of Cadmium Telluride on a Gallium Arsenide Substrate (open access)

Method for Improving the Growth of Cadmium Telluride on a Gallium Arsenide Substrate

A method for preparing a gallium arsenide substrate, prior to growing a layer of cadmium telluride on a support surface thereof. The preparation includes the steps of cleaning the gallium arsenide substrate and thereafter forming prepatterned shapes on the support surface of the gallium arsenide substrate. The layer of cadmium telluride then grown on the prepared substrate results in dislocation densities of approximately 1{times}10{sup 6}/cm{sup 2} or less. The prepatterned shapes on the support surface of the gallium arsenide substrate are formed by reactive ion etching an original outer surface of the gallium arsenide substrate and into the body of the gallium arsenide substrate to a depth of at least two microns. The prepatterned shapes have the appearance of cylindrical mesas each having a diameter of at lease twelve microns. After the mesas are formed on the support surface of the gallium arsenide substrate, the substrate is again cleaned.
Date: December 31, 1990
Creator: Reno, John L.
System: The UNT Digital Library