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Method for Non-Intrusively Identifying a Contained Material Utilizing Uncollided Nuclear Transmission Measurements (open access)

Method for Non-Intrusively Identifying a Contained Material Utilizing Uncollided Nuclear Transmission Measurements

An improved nuclear diagnostic method identifies a contained target material by measuring on-axis, mono-energetic uncollided particle radiation transmitted through a target material for two penetrating radiation beam energies, and applying specially developed algorithms to estimate a ratio of macroscopic neutron cross-sections for the uncollided particle radiation at the two energies, where the penetrating radiation is a neutron beam, or a ratio of linear attenuation coefficients for the uncollided particle radiation at the two energies, where the penetrating radiation is a gamma-ray beam. Alternatively, the measurements are used to derive a minimization formula based on the macroscopic neutron cross-sections for the uncollided particle radiation at the two neutron beam energies, or the linear attenuation coefficients for the uncollided particle radiation at the two gamma-ray beam energies. A candidate target material database, including known macroscopic neutron cross-sections or linear attenuation coefficients for target materials at the selected neutron or gamma-ray beam energies, is used to approximate the estimated ratio or to solve the minimization formula, such that the identity of the contained target material is discovered.
Date: February 26, 1999
Creator: Morrison, John L.; Stephens, Alan G. & S., Grover Blaine
System: The UNT Digital Library
Method of Dehalogenation using Diamonds (open access)

Method of Dehalogenation using Diamonds

A method for preparing olefins and halogenated olefins is provided comprising contacting halogenated compounds with diamonds for a sufficient time and at a sufficient temperature to convert the halogenated compounds to olefins and halogenated olefins via elimination reactions.
Date: February 26, 1999
Creator: Farcasiu, Malvina; Kaufman, Phillip B.; Ladner, Edward P. & Anderson, Richard R.
System: The UNT Digital Library
Method for the Removal of Ultrafine Particulates from an Aqueous Suspension (open access)

Method for the Removal of Ultrafine Particulates from an Aqueous Suspension

A method of separating ultra-fine particulate from an aqueous suspension such as a process stream or a waste stream. The method involves the addition of alkali silicate and an organic gelling agent to a volume of liquid, from the respective process or waste stream, to form a gel. The gel then undergoes syneresis to remove water and soluble salts from the gel-containing the particulate, thus, forming a silica monolith. The silica monolith is then sintered to form a hard, nonporous waste form.
Date: March 5, 1999
Creator: Chaiko, David J.; Kopasz, John P. & Ellison, Adam J. G.
System: The UNT Digital Library
New Carbon Activation Process for Increased Surface Accessibility in Electrochemical Capacitors (open access)

New Carbon Activation Process for Increased Surface Accessibility in Electrochemical Capacitors

A process for making carbon film or powder suitable for double capacitor electrodes having a capacitance of up to about 300 F/cm{sup 3} is disclosed. This is accomplished by treating in aqueous nitric acid for a period of about 5 to 15 minutes thin carbon films obtained by carbonizing carbon-containing polymeric material having a high degree of molecular directionality, such as polyimide film, then heating the treated carbon film in a non-oxidizing atmosphere at a non-graphitizing temperature of at least 350 C for about 20 minutes, and repeating alternately the nitric acid step and the heating step from 7 to 10 times. Capacitors made with this carbon may find uses ranging from electronic devices to electric vehicle applications.
Date: March 16, 1999
Creator: Doughty, Daniel H. & Eisenmann, Erhard T.
System: The UNT Digital Library
Automated Sample collection and Analysis unit (open access)

Automated Sample collection and Analysis unit

Autoramp is an atmospheric radionuclide collection and analysis unit designed for unattended operation. A large volume of air passes through one of 31 filter cartridges which is then moved from a sampling chamber and past a bar code reader, to a shielded enclosure. The collected dust-borne radionuclides are counted with a high resolution germanium gamma-ray detector. An analysis is made and the results are transmitted to a central station that can also remotely control the unit.
Date: March 31, 1999
Creator: Latner, Norman; Sanderson, Colin G. & Negro, Vincent C.
System: The UNT Digital Library
Fluidtight Seal for a Container (open access)

Fluidtight Seal for a Container

A fluidtight seal for a container is formed by abutting a metal ring with a step machined in a convexo-concave container closure device and inserting this assembly into an open end of the container. Under compressive force, the closure device deforms causing the metal ring to pivot about the step on the closure device and interact with symmetrically tapered inner walls of the container to form a fluidtight seal between the container and the closure device. The compressive force is then withdrawn without affecting the fluidtight characteristic of the seal. A destructive force against the container closure device is necessary to destroy the fluidtight seal.
Date: March 31, 1999
Creator: Morrison, Edward F.
System: The UNT Digital Library
Oxidation-resistant interfacial coatings for fiber-reinforced ceramic composites (open access)

Oxidation-resistant interfacial coatings for fiber-reinforced ceramic composites

A ceramic-matrix composite having a multilayered interfacial coating adapted to protect the reinforcing fibers from long-term oxidation, while allowing these to bridge the wake of advancing cracks in the matrix, is provided by selectively mismatching materials within adjacent layers of the interfacial coating, the materials having different coefficients of thermal expansion so that a low toughness interface region is created to promote crack deflection either within an interior layer of the mismatched interfacial coating or between adjacent layers of the mismatched interfacial coating.
Date: April 22, 1999
Creator: Lara-Curzio, Edgar; More, Karren L. & Lee, Woo Y.
System: The UNT Digital Library
Near-Electrode Imager (open access)

Near-Electrode Imager

An apparatus, near-electrode imager, for employing nuclear magnetic resonance imaging to provide in situ measurements of electrochemical properties of a sample as a function of distance from a working electrode. The near-electrode imager use the radio frequency field gradient within a cylindrical toroid cavity resonator to provide high-resolution nuclear magnetic resonance spectral information on electrolyte materials.
Date: May 1, 1999
Creator: Rathke, Jerome W.; Klingler, Robert J.; Woelk, Klaus & Gerald, Rex E., II
System: The UNT Digital Library
X-Ray Imaging Crystal Spectrometer for Extended X-Ray Sources (open access)

X-Ray Imaging Crystal Spectrometer for Extended X-Ray Sources

Spherically or toroidally curved, double focusing crystals are used in a spectrometer for X-ray diagnostics of an extended X-ray source such as a hot plasma produced in a tokamak fusion experiment to provide spatially and temporally resolved data on plasma parameters such as ion temperature, toroidal and poloidal rotation, electron temperature, impurity ion charge-state distributions, and impurity transport. The imaging properties of these spherically or toroidally curved crystals provide both spectrally and spatially resolved X-ray data from the plasma using only one small spherically or toroidally curved crystal, thus eliminating the requirement for a large array of crystal spectrometers and the need to cross-calibrate the various crystals.
Date: May 1, 1999
Creator: Bitter, Manfred L.; Fraekel, Benjamin; Gorman, James L.; Hill, Kenneth W.; Roquemore, Lane A.; Stodiek, Wolfgang et al.
System: The UNT Digital Library
Control Coil Arrangement for a Rotating Machine Rotor (open access)

Control Coil Arrangement for a Rotating Machine Rotor

A rotating machine (e.g., a turbine, motor or generator) is provided wherein a fixed solenoid or other coil configuration is disposed adjacent to one or both ends of the active portion of the machine rotor for producing an axially directed flux in the active portion so as to provide planar axial control at single or multiple locations for rotor balance, levitation, centering, torque and thrust action. Permanent magnets can be used to produce an axial bias magnetic field. The rotor can include magnetic disks disposed in opposed, facing relation to the coil configuration.
Date: May 5, 1999
Creator: Shah, Manoj R. & Lewandowski, Chad R.
System: The UNT Digital Library
Method for Producing Chemically Bonded Phosphate Ceramics and for Stabilizing Contaminants Encapsulated therein Utilizing Reducing Agents (open access)

Method for Producing Chemically Bonded Phosphate Ceramics and for Stabilizing Contaminants Encapsulated therein Utilizing Reducing Agents

Known phosphate ceramic formulations are improved and the ability to produce iron-based phosphate ceramic systems is enabled by the addition of an oxidizing or reducing step during the acid-base reactions that form the phosphate ceramic products. The additives allow control of the rate of the acid-base reactions and concomitant heat generation. In an alternate embodiment, waste containing metal anions is stabilized in phosphate ceramic products by the addition of a reducing agent to the phosphate ceramic mixture. The reduced metal ions are more stable and/or reactive with the phosphate ions, resulting in the formation of insoluble metal species within the phosphate ceramic matrix, such that the resulting chemically bonded phosphate ceramic product has greater leach resistance.
Date: May 5, 1999
Creator: Singh, Dileep; Wagh, Arun S. & Jeong, Seung-Young
System: The UNT Digital Library
Polymer Coating for Immobilizing Soluble Ions in a Phosphate Ceramic Product (open access)

Polymer Coating for Immobilizing Soluble Ions in a Phosphate Ceramic Product

A polymer coating is applied to the surface of a phosphate ceramic composite to effectively immobilize soluble salt anions encapsulated within the phosphate ceramic composite. The polymer coating is made from ceramic materials, including at least one inorganic metal compound, that wet and adhere to the surface structure of the phosphate ceramic composite, thereby isolating the soluble salt anions from the environment and ensuring long-term integrity of the phosphate ceramic composite.
Date: May 5, 1999
Creator: Singh, Dileep; Wagh, Arun S. & Patel, Kartikey D.
System: The UNT Digital Library
Stator for Rotating Electrical Machine Having Multiple Controlwindings (open access)

Stator for Rotating Electrical Machine Having Multiple Controlwindings

A rotating electric machine is provided which includes multiple independent control windings for compensating for rotor imbalances and for levitating/centering the rotor. The multiple independent control windings are placed at different axial locations along the rotor to oppose forces created by imbalances at different axial locations along the rotor. The multiple control windings can also be used to levitate/center the rotor with a relatively small magnetic field per unit area since the rotor and/or the main power winding provides the biasfield.
Date: May 5, 1999
Creator: Shah, Manoj R. & Lewandowski, Chad R.
System: The UNT Digital Library
Mechanical Seal Assembly (open access)

Mechanical Seal Assembly

An improved mechanical seal assembly is provided for sealing rotating shafts with respect to their shaft housings, wherein the rotating shafts are subject to substantial axial vibrations. The mechanical seal assembly generally includes a rotating sealing ring fixed to the shaft, a non-rotating sealing ring adjacent to and in close contact with the rotating sealing ring for forming an annular seal about the shaft, and a mechanical diode element that applies a biasing force to the non-rotating sealing ring by means of hemispherical joint. The alignment of the mechanical diode with respect to the sealing rings is maintained by a series of linear bearings positioned axially along a desired length of the mechanical diode. Alternative embodiments include mechanical or hydraulic amplification components for amplifying axial displacement of the non-rotating sealing ring and transferring it to the mechanical diode.
Date: June 18, 1999
Creator: Kotlyar, Oleg M.
System: The UNT Digital Library
Uniform bulk Material Processing using Multimode Microwave Radiation (open access)

Uniform bulk Material Processing using Multimode Microwave Radiation

An apparatus for generating uniform heating in material contained in a cylindrical vessel is described. TE{sub 10}-mode microwave radiation is coupled into a cylindrical microwave transition such that microwave radiation having TE{sub 11}-, TE{sub 01}- and TM{sub 01}-cylindrical modes is excited therein. By adjusting the intensities of these modes, substantially uniform heating of materials contained in a cylindrical drum which is coupled to the microwave transition through a rotatable choke can be achieved. The use of a poor microwave absorbing insulating cylindrical insert, such as aluminum oxide, for separating the material in the container from the container walls and for providing a volume through which air is circulated is expected to maintain the container walls at room temperature. The use of layer of highly microwave absorbing material, such as SiC, inside of the insulating insert and facing the material to be heated is calculated to improve the heating pattern of the present apparatus.
Date: June 18, 1999
Creator: Varma, Ravi & Vaughan, Worth E.
System: The UNT Digital Library
Ceramic Composition for Immobilization of Actinides (open access)

Ceramic Composition for Immobilization of Actinides

Disclosed is a ceramic composition for the immobilization of actinides, particularly uranium and plutonium. The ceramic is a titanate material comprising pyrochlore, brannerite and rutile.
Date: June 22, 1999
Creator: Ebbinghaus, Bartley B.; Van Konynenburg, Richard A.; Vance, Eric R.; Stewart, Martin W.; Jostsons, Adam; Allender, Jeffrey S. et al.
System: The UNT Digital Library
Process for Making a Ceramic Composition for Immobilization of Actinides (open access)

Process for Making a Ceramic Composition for Immobilization of Actinides

Disclosed is a process for making a ceramic composition for the immobilization of actinides, particularly uranium and plutonium. The ceramic is a titanate material comprising pyrochlore, brannerite and rutile. The process comprises oxidizing the actinides, milling the oxides to a powder, blending them with ceramic precursors, cold pressing the blend and sintering the pressed material.
Date: June 22, 1999
Creator: Ebbinghaus, Bartley B.; Van Konynenburg, Richard A.; Vance, Eric R.; Stewart, Martin W.; Walls, Philip A.; Brummond, William Allen et al.
System: The UNT Digital Library
Abrasion Resistant Coating and Method of making the same (open access)

Abrasion Resistant Coating and Method of making the same

An abrasion resistant coating is created by adding a ductile phase to a brittle matrix phase during spray coating where an Al-Cu-Fe quasicrystalline phase (brittle matrix) and an FeAl intermetallic (ductile phase) are combined. This composite coating produces a coating mostly of quasicrystal phase and an inter-splat layer of the FeAl phase to help reduce porosity and cracking within the coating. Coatings are prepared by plasma spraying unblended and blended quasicrystal and intermetallic powders. The blended powders contain 1, 5, 10 and 20 volume percent of the intermetallic powders. The unblended powders are either 100 volume percent quasicrystalline or 100 volume percent intermetallic; these unblended powders were studied for comparison to the others. Sufficient ductile phase should be added to the brittle matrix to transform abrasive wear mode from brittle fracture to plastic deformation, while at the same time the hardness of the composite should not be reduced below that of the original brittle phase material.
Date: June 25, 1999
Creator: Sordelet, Daniel J. & Besser, Matthew F.
System: The UNT Digital Library
Vacuum Enhanced Cutaneous Biopsy Instrument (open access)

Vacuum Enhanced Cutaneous Biopsy Instrument

A syringe-like disposable cutaneous biopsy instrument equipped with a tubular blade at its lower end, and designed so that a vacuum is created during use, said vacuum serving to retain undeformed a plug of tissue cut from a patient's skin.
Date: June 25, 1999
Creator: Collins, Joseph
System: The UNT Digital Library
A Monolithic Interconnected module with a tunnel Junction for Enhanced Electrical and Optical Performance (open access)

A Monolithic Interconnected module with a tunnel Junction for Enhanced Electrical and Optical Performance

An improved thermophotovoltaic (TPV) n/p/n device is provided. Monolithic Interconnected Modules (MIMs), semiconductor devices converting infrared radiation to electricity, have been developed with improved electrical and optical performance. The structure is an n-type emitter on a p-type base with an n-type lateral conduction layer. The incorporation of a tunnel junction and the reduction in the amount of p-type material used results in negligible parasitic absorption, decreased series resistance, increased voltage and increased active area. The novel use of a tunnel junction results in the potential for a TPV device with efficiency greater than 24%.
Date: June 30, 1999
Creator: Murray, Christopher Sean & Wilt, David Morgan
System: The UNT Digital Library
Gas-Driven Microturbine (open access)

Gas-Driven Microturbine

The present invention is directed to a means of fabricating a gas-driven microturbine that is capable of providing autonomous propulsion in which the rapidly moving gases are directed through a micromachined turbine to power mechanical, electrical, or electromechanical devices by direct mechanical linkage of turbo-electric generator components in a domain ranging from tenths of micrometers to thousands of micrometers. By optimally selecting monopropellants or bipropellants to be the fuel set, a more efficient gas-driven microturbine can be realized from the increased mass flow rate of the gas stream due to the higher combustion reaction energies of these fuel sets. Additionally, compressed gas can be utilized to provide a high-flow gas stream for the gas-driven microturbine. The present invention is adaptable to many defense and non-defense applications, including the provision of mechanical power for miniature devices such as fans, geared mechanisms, mechanical linkages, actuators, bio-medical procedures, manufacturing, industrial, aviation, computers, safety systems, and electrical generators.
Date: July 14, 1999
Creator: Sniegowski, Jeffrey J.; Rodgers, Murray S.; McWhorter, Paul J.; Aeschliman, Daniel P. & Miller, William M.
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: July 15, 1999
Creator: Ochs, Thomas L.; Sands, William D.; Schroeder, Karl; Summers, Cathy A. & Utz, Bruce R.
System: The UNT Digital Library
Ultrasonic Sensor and Method of use (open access)

Ultrasonic Sensor and Method of use

An ultrasonic sensor system and method of use for measuring transit time through a liquid sample, comprising at least one ultrasonic transducer coupled to a precision time interval counter. The timing circuit captures changes in transit time, representing small changes in the velocity of sound transmitted, over necessarily small time intervals (nanoseconds) and uses the transit time changes to identify the presence of non-conforming constituents in the sample.
Date: July 22, 1999
Creator: Condreva, Kenneth J.
System: The UNT Digital Library
Portable Apparatus for the Measurement of Environmental Radon and Thoron (open access)

Portable Apparatus for the Measurement of Environmental Radon and Thoron

The radometer is a portable instrument for the measurement of the concentration of atmospheric radon/thoron in a test area. A constant velocity pump pulls the air from the outside at a constant flow rate. If the air is too moist, some or all of the sample is passed through a desiccant filter prior to encountering an electrostatic filter. The electrostatic filter prevents any charged particles from entering the sampling chamber. Once the sample has entered the chamber, the progeny of the decay of radon/thoron are collected on a detector and measured. The measured data is compiled by a computer and displayed.
Date: August 19, 1999
Creator: Negro, Vincent
System: The UNT Digital Library