High Specific Surface area Aerogel Cryoadsorber for Vacuum Pumping Applications (open access)

High Specific Surface area Aerogel Cryoadsorber for Vacuum Pumping Applications

A cryogenic pumping system is provided, comprising a vacuum environment, an aerogel sorbent formed from a carbon aerogel disposed within the vacuum environment, and cooling means for cooling the aerogel sorbent sufficiently to adsorb molecules from the vacuum environment onto the aerogel sorbent. Embodiments of the invention include a liquid refrigerant cryosorption pump, a compressed helium cryogenic pump, a cryopanel and a Meissner coil, each of which uses carbon aerogel as a sorbent material.
Date: December 22, 1998
Creator: Hill, Randal M.; Fought, Eric R. & Biltoft, Peter J.
System: The UNT Digital Library
Electrochemical Membrane Incinerator (open access)

Electrochemical Membrane Incinerator

Electrochemical incineration of benzoquinone was evaluated as a model for the mineralization of carbon in toxic aromatic compounds. A Ti or Pt anode was coated with a film of the oxides of Ti, Ru, Sn and Sb. This quaternary metal oxide film was stable; elemental analysis of the electrolyzed solution indicated the concentration of these metal ions to be 3 {micro}g/L or less. The anode showed good reactivity for the electrochemical incineration of benzoquinone. The use of a dissolved salt matrix as the so-called ''supporting electrolyte'' was eliminated in favor of a solid-state electrolyte sandwiched between the anode and cathode.
Date: December 8, 1998
Creator: Johnson, Dennis C.; Houk, Linda L. & Feng, Jianren
System: The UNT Digital Library
Method for Plutonium-Gallium Separation by Anodic Dissolution of a Solid Plutonium-Gallium Alloy (open access)

Method for Plutonium-Gallium Separation by Anodic Dissolution of a Solid Plutonium-Gallium Alloy

Purified plutonium and gallium are efficiently recovered from a solid plutonium-gallium (Pu-Ga) alloy by using an electrorefining process. The solid Pu-Ga alloy is the cell anode, preferably placed in a moving basket within the electrolyte. As the surface of the Pu-Ga anode is depleted in plutonium by the electrotransport of the plutonium to a cathode, the temperature of the electrolyte is sufficient to liquify the surface, preferably at about 500 C, resulting in a liquid anode layer substantially comprised of gallium. The gallium drips from the liquified surface and is collected below the anode within the electrochemical cell. The transported plutonium is collected on the cathode surface and is recovered.
Date: December 8, 1998
Creator: Miller, William E. & Tomczuk, Zygmunt
System: The UNT Digital Library
Drum bubbler tritium processing system (open access)

Drum bubbler tritium processing system

A method is described for separating tritium oxide from a gas stream containing tritium oxide. The gas stream containing tritium oxide is fed into a container of water having a head space above the water. Bubbling the gas stream containing tritium oxide through the container of water and removing gas from the container head space above the water. Thereafter, the gas from the head space is dried to remove water vapor from the gas, and the water vapor is recycled to the container of water.
Date: December 1, 1998
Creator: Rule, Keith; Gettelfinger, Geoff & Kivler, Paul
System: The UNT Digital Library
Fatty acyl-CoA reductase (open access)

Fatty acyl-CoA reductase

The present invention relates to bacterial enzymes, in particular to an acyl-CoA reductase and a gene encoding an acyl-CoA reductase, the amino acid and nucleic acid sequences corresponding to the reductase polypeptide and gene, respectively, and to methods of obtaining such enzymes, amino acid sequences and nucleic acid sequences. The invention also relates to the use of such sequences to provide transgenic host cells capable of producing fatty alcohols and fatty aldehydes.
Date: December 1, 1998
Creator: Reiser, Steven E. & Somerville, Chris R.
System: The UNT Digital Library
Method for direct production of carbon disulfide and hydrogen from hydrocarbons and hydrogen sulfide feedstock (open access)

Method for direct production of carbon disulfide and hydrogen from hydrocarbons and hydrogen sulfide feedstock

A method for converting hydrocarbons and hydrogen sulfide to carbon disulfide and hydrogen is provided comprising contacting the hydrocarbons and hydrogen sulfide to a bi-functional catalyst residing in a controlled atmosphere for a time and at a temperature sufficient to produce carbon disulfide and hydrogen. Also provided is a catalyst for converting carbon sulfides and hydrogen sulfides to gasoline range hydrocarbons comprising a mixture containing a zeolite catalyst and a hydrogenating catalyst.
Date: December 1998
Creator: Miao, F. Q. & Erekson, E. J.
System: The UNT Digital Library
Nanodisperse transition metal electrodes (NTME) for electrochemical cells (open access)

Nanodisperse transition metal electrodes (NTME) for electrochemical cells

Disclosed are transition metal electrodes for electrochemical cells using gel-state and solid-state polymers. The electrodes are suitable for use in primary and secondary cells. The electrodes (either negative electrode or positive electrode) are characterized by uniform dispersion of the transition metal at the nanoscale in the polymer. The transition metal moiety is structurally amorphous, so no capacity fade should occur due to lattice expansion/contraction mechanisms. The small grain size, amorphous structure and homogeneous distribution provide improved charge/discharge cycling performance, and a higher initial discharge rate capability. The cells can be cycled at high current densities, limited only by the electrolyte conductivity. A method of making the electrodes (positive and negative), and their usage in electrochemical cells are disclosed.
Date: December 1, 1998
Creator: Striebel, Kathryn A. & Wen, Shi-Jie
System: The UNT Digital Library
Oxide strengthened molybdenum-rhenium alloy (open access)

Oxide strengthened molybdenum-rhenium alloy

Provided is a method of making an ODS molybdenum-rhenium alloy which includes the steps of: (1) forming a slurry containing molybdenum oxide and a metal salt dispersed in an aqueous medium, the metal salt being selected from nitrates or acetates of lanthanum, cerium or thorium; (2) heating the slurry in the presence of hydrogen to form a molybdenum powder comprising molybdenum and an oxide of the metal salt; (3) mixing rhenium powder with the molybdenum powder to form a molybdenum-rhenium powder; (4) pressing the molybdenum-rhenium powder to form a molybdenum-rhenium compact; (5) sintering the molybdenum-rhenium compact in hydrogen or under a vacuum to form a molybdenum-rhenium ingot; and (6) compacting the molybdenum-rhenium ingot to reduce the cross-sectional area of the molybdenum-rhenium ingot and form a molybdenum-rhenium alloy containing said metal oxide. The present invention also provides an ODS molybdenum-rhenium alloy made by the method.
Date: December 1, 1998
Creator: Bianco, Robert & Buckman, William R. Jr.
System: The UNT Digital Library
Periodic equivalence ratio modulation method and apparatus for controlling combustion instability (open access)

Periodic equivalence ratio modulation method and apparatus for controlling combustion instability

The periodic equivalence ratio modulation (PERM) method and apparatus significantly reduces and/or eliminates unstable conditions within a combustion chamber. The method involves modulating the equivalence ratio for the combustion device, such that the combustion device periodically operates outside of an identified unstable oscillation region. The equivalence ratio is modulated between preselected reference points, according to the shape of the oscillation region and operating parameters of the system. Preferably, the equivalence ratio is modulated from a first stable condition to a second stable condition, and, alternatively, the equivalence ratio is modulated from a stable condition to an unstable condition. The method is further applicable to multi-nozzle combustor designs, whereby individual nozzles are alternately modulated from stable to unstable conditions. Periodic equivalence ratio modulation (PERM) is accomplished by active control involving periodic, low frequency fuel modulation, whereby low frequency fuel pulses are injected into the main fuel delivery. Importantly, the fuel pulses are injected at a rate so as not to affect the desired time-average equivalence ratio for the combustion device.
Date: December 1, 1998
Creator: Richards, George A.; Janus, Michael C. & Griffith, Richard A.
System: The UNT Digital Library
Process for strengthening aluminum based ceramics and material (open access)

Process for strengthening aluminum based ceramics and material

A process for strengthening aluminum based ceramics is provided. A gaseous atmosphere consisting essentially of silicon monoxide gas is formed by exposing a source of silicon to an atmosphere consisting essentially of hydrogen and a sufficient amount of water vapor. The aluminum based ceramic is exposed to the gaseous silicon monoxide atmosphere for a period of time and at a temperature sufficient to produce a continuous, stable silicon-containing film on the surface of the aluminum based ceramic that increases the strength of the ceramic.
Date: December 1, 1998
Creator: Moorhead, Arthur J. & Kim, Hyoun-Ee
System: The UNT Digital Library
A rigid porous filter and filtration method (open access)

A rigid porous filter and filtration method

The present invention involves a porous rigid filter comprising a plurality of concentric filtration elements having internal flow passages and forming external flow passages there between. The present invention also involves a pressure vessel containing the filter for the removal of particulate from high pressure particulate containing gases, and further involves a method for using the filter to remove such particulate. The present filter has the advantage of requiring fewer filter elements due to the high surface area- to-volume ratio provided by the filter, requires a reduced pressure vessel size, and exhibits enhanced mechanical design properties, improved cleaning properties, configuration options, modularity and ease of fabrication.
Date: December 1998
Creator: Chiang, Ta-Kuan; Straub, Douglas, Straub L. & Dennis, Richard A.
System: The UNT Digital Library
Self-seeded injection-locked FEL amplifier (open access)

Self-seeded injection-locked FEL amplifier

A self-seeded free electron laser (FEL) provides a high gain and extraction efficiency for the emitted light. An accelerator outputs a beam of electron pulses to a permanent magnet wiggler having an input end for receiving the electron pulses and an output end for outputting light and the electron pulses. An optical feedback loop collects low power light in a small signal gain regime at the output end of said wiggler and returns the low power light to the input end of the wiggler while outputting high power light in a high signal gain regime.
Date: December 1, 1998
Creator: Sheffield, Richard L.
System: The UNT Digital Library
Solar reduction of CO{sub 2} (open access)

Solar reduction of CO{sub 2}

The red shift of the absorption spectrum of CO{sub 2} with increasing temperature, along with CO stabilization are the foundation of a process for direct solar reduction of CO{sub 2} to liquid fuels. The result is a process capable of using renewable solar energy to directly reduce CO{sub 2} from the atmosphere or stationary sources for recycle as a liquid fuel resulting in a net decrease in CO{sub 2} in the atmosphere and decreased demand on fossil fuel. The process includes in sequence: preparation of adequately pure CO{sub 2} feed; preheating CO{sub 2} to near 1,800 K; breaking the CO{sub 2} bonds to produce CO, O{sub 2} and O; quenching the hot product mix by rapid admixture with room temperature CO{sub 2}; removing excess thermal energy to produce electricity, heat new CO{sub 2} and enable subsequent process steps; removing the remaining CO{sub 2} from the gas; removing oxygen from the gas; converting part of the product CO to H{sub 2} by the shift reaction; and, finally, catalytically synthesizing methanol from the synthetic gas.
Date: December 1, 1998
Creator: Jensen, Reed J.; Lyman, John L.; King, Joe D. & Guettler, Robert D.
System: The UNT Digital Library
Thermionic converter with differentially heated cesium-oxygen source and method of operation (open access)

Thermionic converter with differentially heated cesium-oxygen source and method of operation

A thermionic converter having an emitter, a collector, and a source of cesium vapor is provided, wherein the source of cesium vapor is differentially heated so that said source has a hotter end and a cooler end, with cesium vapor evaporating from said hotter end into the space between the emitter and the collector and with cesium vapor condensing at said cooler end. The condensed cesium vapor migrates through a porous element from the cooler end to the hotter end.
Date: December 1, 1998
Creator: Rasor, N. S.; Riley, D. R.; Murray, C. S. & Geller, C. B.
System: The UNT Digital Library
A unique method of neutron flux determination from experimental data (open access)

A unique method of neutron flux determination from experimental data

A method is provided for determining the fission heat flux of a prime specimen inserted into a specimen of a test reactor. A pair of thermocouple test specimens are positioned at the same level in the holder and a determination is made of various experimental data including the temperature of the thermocouple test specimens, the temperature of bulk water channels located in the test holder, the gamma scan count ratios for the thermocouple test specimens and the prime specimen, and the thicknesses of the outer clads, the fuel fillers, and the backclad of the thermocouple test specimen. Using this experimental data, the absolute value of the fission heat flux for the thermocouple test specimens and prime specimen can be calculated.
Date: December 1, 1998
Creator: Paxton, Frank A.
System: The UNT Digital Library
Directly Susceptible, Noncarbon Composite Crucible (open access)

Directly Susceptible, Noncarbon Composite Crucible

A sintered metal ceramic crucible suitable for high temperature induction melting of reactive metals without appreciable carbon or silicon contamination of the melt. The crucible comprises a cast matrix of a thermally conductive ceramic material; a perforated metal sleeve, which serves as a susceptor for induction heating of the crucible, embedded within the ceramic cast matrix; and a thermal-shock-absorber barrier interposed between the metal sleeve and the ceramic cast matrix to allow for differential thermal expansions between the matrix and the metal sleeve and to act as a thermal-shock-absorber which moderates the effects of rapid changes of sleeve temperature on the matrix.
Date: November 25, 1998
Creator: Holcombe, Cressie E., Jr.; Kiggans, James O., Jr.; Morrow, S. Marvin & Rexford, Donald
System: The UNT Digital Library
Design for Ceramic Membrane Reactor with two Reactant Gases at Different Pressures (open access)

Design for Ceramic Membrane Reactor with two Reactant Gases at Different Pressures

The invention is a ceramic membrane reactor for syngas production having a reaction chamber, an inlet in the reactor for natural gas intake, a plurality of oxygen permeating ceramic slabs inside the reaction chamber with each slab having a plurality of passages paralleling the gas flow for transporting air through the reaction chamber, a manifold affixed to one end of the reaction chamber for intake of air connected to the slabs, a second manifold affixed to the reactor for removing the oxygen depleted air, and an outlet in the reaction chamber for removing syngas.
Date: November 18, 1998
Creator: Balachandran, Uthamalingam & Mieville, Rodney L.
System: The UNT Digital Library
Method and Apparatus for Monitoring the Integrity of a Geomembrane Liner using time Domain Reflectometry (open access)

Method and Apparatus for Monitoring the Integrity of a Geomembrane Liner using time Domain Reflectometry

Leaks are detected in a multi-layered geomembrane liner by a two-dimensional time domain reflectometry (TDR) technique. The TDR geomembrane liner is constructed with an electrically conductive detection layer positioned between two electrically non-conductive dielectric layers, which are each positioned between the detection layer and an electrically conductive reference layer. The integrity of the TDR geomembrane liner is determined by generating electrical pulses within the detection layer and measuring the time delay for any reflected electrical energy caused by absorption of moisture by a dielectric layer.
Date: November 9, 1998
Creator: Morris, John L.
System: The UNT Digital Library
Method and Apparatus for measuring Gravitational Acceleration Utilizing a high Temperature Superconducting Bearing (open access)

Method and Apparatus for measuring Gravitational Acceleration Utilizing a high Temperature Superconducting Bearing

Gravitational acceleration is measured in all spatial dimensions with improved sensitivity by utilizing a high temperature superconducting (HTS) gravimeter. The HTS gravimeter is comprised of a permanent magnet suspended in a spaced relationship from a high temperature superconductor, and a cantilever having a mass at its free end is connected to the permanent magnet at its fixed end. The permanent magnet and superconductor combine to form a bearing platform with extremely low frictional losses, and the rotational displacement of the mass is measured to determine gravitational acceleration. Employing a high temperature superconductor component has the significant advantage of having an operative temperature at or below 77K, whereby cooling maybe accomplished with liquid nitrogen.
Date: November 6, 1998
Creator: Hull, John R.
System: The UNT Digital Library
Statistically Qualified Neuro-Analytic system and Method for Process Monitoring (open access)

Statistically Qualified Neuro-Analytic system and Method for Process Monitoring

An apparatus and method for monitoring a process involves development and application of a statistically qualified neuro-analytic (SQNA) model to accurately and reliably identify process change. The development of the SQNA model is accomplished in two steps: deterministic model adaption and stochastic model adaptation. Deterministic model adaption involves formulating an analytic model of the process representing known process characteristics,augmenting the analytic model with a neural network that captures unknown process characteristics, and training the resulting neuro-analytic model by adjusting the neural network weights according to a unique scaled equation emor minimization technique. Stochastic model adaptation involves qualifying any remaining uncertainty in the trained neuro-analytic model by formulating a likelihood function, given an error propagation equation, for computing the probability that the neuro-analytic model generates measured process output. Preferably, the developed SQNA model is validated using known sequential probability ratio tests and applied to the process as an on-line monitoring system.
Date: November 4, 1998
Creator: Vilim, Richard B.; Garcia, Humberto E. & Chen, Frederick W.
System: The UNT Digital Library
Device for Detecting Actinides, Method for Detecting Actinides (open access)

Device for Detecting Actinides, Method for Detecting Actinides

A heavy metal detector is provided comprising a first molecule and a second molecule, whereby the first and second molecules interact in a predetermined manner; a first region on the first molecule adapted to interact with an actinide; and a second region on the second molecule adapted to interact with the actinide, whereby the interactions of the actinide with the regions effect the predetermined manner of interaction between the molecules.
Date: October 29, 1998
Creator: Stevens, Fred J. & Wilkins-Stevens, Priscilla
System: The UNT Digital Library
Method and Apparatus to Produce and Maintain a thick, flowing, Liquid Lithium first wall for Toroidal Magnetic Confinement DT Fusion Reactors (open access)

Method and Apparatus to Produce and Maintain a thick, flowing, Liquid Lithium first wall for Toroidal Magnetic Confinement DT Fusion Reactors

A system for forming a thick flowing liquid metal, in this case lithium, layer on the inside wall of a toroid containing the plasma of a deuterium-tritium fission reactor. The presence of the liquid metal layer or first wall serves to prevent neutron damage to the walls of the toroid. A poloidal current in the liquid metal layer is oriented so that it flows in the same direction as the current in a series of external magnets used to confine the plasma. This current alignment results in the liquid metal being forced against the wall of the toroid. After the liquid metal exits the toroid it is pumped to a heat extraction and power conversion device prior to being reentering the toroid.
Date: October 21, 1998
Creator: Woolley, Robert D.
System: The UNT Digital Library
Method for measuring Particulate and Gaseous Metals in a fluid stream, Device for measuring Particulate and Gaseous Metals in a fluid stream (open access)

Method for measuring Particulate and Gaseous Metals in a fluid stream, Device for measuring Particulate and Gaseous Metals in a fluid stream

A method for analyzing metal in a fluid is provided comprising maintaining a first portion of a continuous filter media substrate at a temperature coinciding with the phase in which the metal is to be analyzed; contacting the fluid to a first portion of said substrate to retain the metal on the first portion of said substrate; preventing further contact of the fluid to the first portion of substrate; and contacting the fluid to a second portion of said substrate to retain metal on the second portion of the said substrate while simultaneously analyzing the first portion for metal. Also provided is a device for the simultaneous monitoring and analysis of metal in a fluid comprising a continuous filter media substrate; means for maintaining a first portion of said filter media substrate at a temperature coinciding with the phase in which the metal is to be analyzed; a means for contacting the fluid to the first portion of said substrate; a means for preventing further contact of the fluid to the first portion of substrate; a means for contacting the fluid to a second portion of said substrate to retain metal on the second portion of the said substrate; and …
Date: October 21, 1998
Creator: Farber, Paul S. & Huang, Hann-Shen
System: The UNT Digital Library
Rack Protection Monitor (open access)

Rack Protection Monitor

A hardwired, fail-safe rack protection monitor utilizes electromechanical relays to respond to the detection by condition sensors of abnormal or alarm conditions (such as smoke, temperature, wind or water) that might adversely affect or damage equipment being protected. When the monitor is reset, the monitor is in a detection mode with first and second alarm relay coils energized. If one of the condition sensors detects an abnormal condition, the first alarm relay coil will be de-energized, but the second alarm relay coil will remain energized. This results in both a visual and an audible alarm being activated. If a second alarm condition is detected by another one of the condition sensors while the first condition sensor is still detecting the first alarm condition, both the first alarm relay coil and the second alarm relay coil will be de-energized. With both the first and second alarm relay coils de-energized, both a visual and an audible alarm will be activated. In addition, power to the protected equipment will be terminated and an alarm signal will be transmitted to an alarm central control. The monitor can be housed in a separate enclosure so as to provide an interface between a power supply for …
Date: October 21, 1998
Creator: Orr, Stanley G.
System: The UNT Digital Library