36 Matching Results

Results open in a new window/tab.

Method of Forming Diamonds from Carbonaceous Material (open access)

Method of Forming Diamonds from Carbonaceous Material

A method for producing diamonds is provided comprising exposing carbonaceous material to ion irradiation at ambient temperature and pressure.
Date: November 30, 1999
Creator: Daulton, Tyrone; Lewis, Roy; Rehn, Lynn & Kirk, Marquis
System: The UNT Digital Library
Planar fuel cell utilizing nail current collectors for increased active surface area (open access)

Planar fuel cell utilizing nail current collectors for increased active surface area

A plurality of nail current collector members are useful in the gas flow passages of an electrochemical device to optimize the active surfaces of the device and to provide structural support. In addition, the thicknesses of cathode and anode layers within the electrochemical device are varied according to current flow through the device to reduce resistance and increase operating efficiency.
Date: November 26, 1999
Creator: George, Thomas J. & Meacham, G.B. Kirby
System: The UNT Digital Library
Low Loss Composition of BA{sub X}SR{sub Y}CA{sub 1-X-Y}TIO{sub 3}:BA{sub 0.12-0.25}SR{sub 0.35-0.47}CA{sub 0.32-0.53}TIO{sub 3} (open access)

Low Loss Composition of BA{sub X}SR{sub Y}CA{sub 1-X-Y}TIO{sub 3}:BA{sub 0.12-0.25}SR{sub 0.35-0.47}CA{sub 0.32-0.53}TIO{sub 3}

A dielectric thin-film material for microwave applications, including use as a capacitor, the thin-film comprising a composition of barium strontium calcium and titanium of perovskite type (Ba{sub x}Sr{sub y}Ca{sub 1-x-y})TiO{sub 3}. Also provided is a method for making a dielectric thin film of that formula over a wide compositional range through a single deposition process.
Date: October 19, 1999
Creator: Xiang, Xiao-Dong; Chang, Hauyee & Takeuchi, Ichiro
System: The UNT Digital Library
Bi-Stable Optical Actuator (open access)

Bi-Stable Optical Actuator

The present invention is a bi-stable optical actuator device that is depowered in both stable positions. A bearing is used to transfer motion and smoothly transition from one state to another. The optical actuator device may be maintained in a stable position either by gravity or a restraining device.
Date: October 15, 1999
Creator: Holdener, Fred R. & Boyd, Robert D.
System: The UNT Digital Library
Novel Solvent for the Simultaneous recovery of Radioactive Nuclides from Liquid Radioactive Wastes (open access)

Novel Solvent for the Simultaneous recovery of Radioactive Nuclides from Liquid Radioactive Wastes

The present invention relates to solvents, and methods, for selectively extracting and recovering radionuclides, especially cesium and strontium, rare earths and actinides from liquid radioactive wastes. More specifically, the invention relates to extracting agent solvent compositions comprising complex organoboron compounds, substituted polyethylene glycols, and neutral organophosphorus compounds in a diluent. The preferred solvent comprises a chlorinated cobalt dicarbollide, diphenyl-dibutylmethylenecarbamoylphosphine oxide, PEG-400, and a diluent of phenylpolyfluoroalkyl sulfone. The invention also provides a method of using the invention extracting agents to recover cesium, strontium, rare earths and actinides from liquid radioactive waste.
Date: October 7, 1999
Creator: Romanovskiy, Valeriy Nicholiavich; Smirnov, Lgor V.; Babain, Vasiliy A.; Todd, Terry A. & Brewer, Ken N.
System: The UNT Digital Library
Low Temperature Sorbents for removal of Sulfur Compounds from fluid feed Streams (open access)

Low Temperature Sorbents for removal of Sulfur Compounds from fluid feed Streams

A sorbent material is provided comprising a material reactive with sulfur, a binder unreactive with sulfur and an inert material, wherein the sorbent absorbs the sulfur at temperatures between 30 and 200 C. Sulfur absorption capacity as high as 22 weight percent has been observed with these materials.
Date: September 30, 1999
Creator: Siriwardane, Ranjan
System: The UNT Digital Library
In-situ method to remove iron and other metals from Solution in Groundwater down Gradient from Permeable Reactive Barrier (open access)

In-situ method to remove iron and other metals from Solution in Groundwater down Gradient from Permeable Reactive Barrier

This invention is directed to a process for treating the flow of anaerobic groundwater through an aquifer with a primary treatment media, preferably iron, and then passing the treated groundwater through a second porous media though which an oxygenated gas is passed in order to oxygenate the dissolved primary treatment material and convert it into an insoluble material thereby removing the dissolved primary treatment material from the groundwater.
Date: September 22, 1999
Creator: Carpenter, Clay E. & Morrison, Stanley J.
System: The UNT Digital Library
A method to remove Ammonia using a Proton-Conducting Ceramic Membrane (open access)

A method to remove Ammonia using a Proton-Conducting Ceramic Membrane

An apparatus and method for decomposing NH{sub 3}. A fluid containing NH{sub 3} is passed in contact with a tubular membrane that is a homogeneous mixture of a ceramic and a first metal, with the ceramic being selected from one or more of a cerate having the formula of M' Ce{sub 1-x} M''O{sub 3-{delta}}, zirconates having the formula M'Zr{sub 1-x} M''3-{delta}, stannates having the formula M'Sn{sub 1-x}M''O{sub 3}-{delta}, where M' is a group IIA metal, M'' is a dopant metal of one or more of Ca, Y, Yb, In, Nd, Gd or mixtures thereof and {delta} is a variable depending on the concentration of dopant and is in the range of from 0.001 to 0.5, the first metal is a group VIII or group IB element selected from the group consisting of Pt, Ag, Pd, Fe, Co, Cr, Mn, V, Ni, Au, Cu, Rh, Ru and mixtures thereof. The tubular membrane has a catalytic metal on the side thereof in contact with the fluid containing NH{sub 3} which is effective to cause NH{sub 3} to decompose to N{sub 2} and H{sub 2}. When the H{sub 2} contacts the membrane, H{sup +} ions are formed which pass through the membrane driving …
Date: September 22, 1999
Creator: Balachandran, Uthamalingam & Bose, Arun C.
System: The UNT Digital Library
Aerogel Fingerprint Media (open access)

Aerogel Fingerprint Media

A fingerprint medium which is made of an aerogel having a predetermined density. The fingerprint medium may have a midrange density for forming plates or may be crushed forming a powder. The fingerprint medium may further include at least one of a metal and metal oxide to enhance characteristics desirable in a fingerprint medium.
Date: September 21, 1999
Creator: Miller, Fred S. & Andresen, Brian D.
System: The UNT Digital Library
Cryogenic Homogenization and Sampling of Heterogeneous Multi-Phase Feedstock (open access)

Cryogenic Homogenization and Sampling of Heterogeneous Multi-Phase Feedstock

An apparatus and process for producing a homogeneous analytical sample from a heterogeneous feedstock by: providing the mixed feedstock, reducing the temperature of the feedstock to a temperature below a critical temperature, reducing the size of the feedstock components, blending the reduced size feedstock to form a homogeneous mixture; and obtaining a representative sample of the homogeneous mixture. The size reduction and blending steps are performed at temperatures below the critical temperature in order to retain organic compounds in the form of solvents, oils, or liquids that may be adsorbed onto or absorbed into the solid components of the mixture, while also improving the efficiency of the size reduction. Preferably, the critical temperature is less than 77K (-196 C). Further, with the process of this invention the representative sample maybe maintained below the critical temperature until being analyzed.
Date: September 21, 1999
Creator: Doyle, Glenn M.; Ideker, Virgene D. & Siegwarth, James D.
System: The UNT Digital Library
Hydrogen gettering packing material and process for making same (open access)

Hydrogen gettering packing material and process for making same

A hydrogen gettering system for a sealed container is disclosed comprising packing material for use within the sealed container, and a coating film containing hydrogen gettering material on at least a portion of the surface of such packing material. The coating film containing the hydrogen gettering material comprises a mixture of one or more organic materials capable of reacting with hydrogen and one or more catalysts capable of catalyzing the reaction of hydrogen with such one or more organic materials. The mixture of one or more organic materials capable of reacting with hydrogen and the one or more catalysts is dispersed in a suitable carrier which preferably is a curable film-forming material. In a preferred embodiment, the packing material comprises a foam material which is compatible with the coating film containing hydrogen gettering material thereon.
Date: September 9, 1999
Creator: LeMay, James D.; Thompson, Lisa M.; Smith, Henry Michael & Schicker, James R.
System: The UNT Digital Library
Thermionic Converter Temperature Controller (open access)

Thermionic Converter Temperature Controller

A method and apparatus for controlling the temperature of a thermionic reactor over a wide range of operating power, including a thermionic reactor having a plurality of integral cesium reservoirs, a honeycomb material disposed about the reactor which has a plurality of separated cavities, a solid sheath disposed about the honeycomb material and having an opening therein communicating with the honeycomb material and cavities thereof, and a shell disposed about the sheath for creating a coolant annulus therewith so that the coolant in the annulus may fill the cavities and permit nucleate boiling during the operation of the reactor.
Date: August 23, 1999
Creator: Shaner,B. J.; Wolf, Joseph H. & Johnson, Robert G. R.
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
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
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
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
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
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
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
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
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