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In-Situ Containment and Extraction of Volatile Soil Contaminants
The invention relates to a novel approach to containing and removing toxic waste from a subsurface environment. More specifically the present invention relates to a system for containing and removing volatile toxic chemicals from a subsurface environment using differences in surface and subsurface pressures. The present embodiment generally comprises a deep well, a horizontal tube, at least one injection well, at least one extraction well and a means for containing the waste within the waste zone (in-situ barrier). During operation the deep well air at the bottom of well (which is at a high pressure relative to the land surface as well as relative to the air in the contaminated soil) flows upward through the deep well (or deep well tube). This stream of deep well air is directed into the horizontal tube, down through the injection tube(s) (injection well(s)) and into the contaminate plume where it enhances volatization and/or removal of the contaminants.
Date:
December 27, 2005
Creator:
Varvel, Mark Darrell
System:
The UNT Digital Library
Near-Field Magneto-Optical Microscope
A device and method for mapping magnetic fields of a sample at a resolution less than the wavelength of light without altering the magnetic field of the sample is disclosed. A device having a tapered end portion with a magneto-optically active particle positioned at the distal end thereof in communication with a fiber optic for transferring incoming linearly polarized light from a source thereof to the particle and for transferring reflected light from the particle is provided. The fiber optic has a reflective material trapping light within the fiber optic and in communication with a light detector for determining the polarization of light reflected from the particle as a function of the strength and direction of the magnetic field of the sample. Linearly polarized light from the source thereof transferred to the particle positioned proximate the sample is affected by the magnetic field of the sample sensed by the particle such that the difference in polarization of light entering and leaving the particle is due to the magnetic field of the sample. Relative movement between the particle and sample enables mapping.
Date:
December 6, 2005
Creator:
Vlasko-Vlasov, Vitalii; Welp, Ulrich & and Crabtree, George W.
System:
The UNT Digital Library
Low-Temperature Synthesis of Actinide Tetraborides by Solid-State Metathesis Reactions
The synthesis of actinide tetraborides including uranium tetraboride (UB,), plutonium tetraboride (PUB,) and thorium tetraboride (ThB{sub 4}) by a solid-state metathesis reaction are demonstrated. The present method significantly lowers the temperature required to {approx_equal}850 C. As an example, when UCl{sub 4}, is reacted with an excess of MgB{sub 2}, at 850 C, crystalline UB, is formed. Powder X-ray diffraction and ICP-AES data support the reduction of UCl{sub 3}, as the initial step in the reaction. The UB, product is purified by washing water and drying.
Date:
December 14, 2004
Creator:
Lupinetti, Anthony J.; Garcia, Eduardo & Abney, Kent D.
System:
The UNT Digital Library
Method and Apparatus for Atomizing Fluids with a Multi-Fluid Nozzle
The invention relates to a method and apparatus for atomizing liquids. In particular, the present invention relates to a method and apparatus for atomizing heavy hydrocarbon fuels such as diesel, as part of a fuel reforming process. During normal operating conditions the fuel is atomized by a high pressure fluid. Under start-up conditions when only a low pressure gas is available the fuel films across part of the nozzle and is subsequently atomized by a radially directed low pressure dispersion gas.
Date:
December 7, 2004
Creator:
Novick, Vincent J. & Ahluwalia, Rajesh K.
System:
The UNT Digital Library
Method for processing aluminum spent potliner in a graphite electrode arc furnace
A method of processing spent aluminum pot liner containing carbon, cyanide compositions, fluorides and inorganic oxides. The spend aluminum pot liner is crushed, iron oxide is added to form an agglomerated material. The agglomerated material is melted in an electric arc furnace having the electrodes submerged in the molten material to provide a reducing environment during the furnace operation. In the reducing environment, pot liner is oxidized while the iron oxides are reduced to produce iron and a slag substantially free of cyanide compositions and fluorides. An off-gas including carbon oxides and fluorine is treated in an air pollution control system with an afterburner and a scrubber to produce NaF, water and a gas vented to the atmosphere free of cyanide compositions, fluorine, and CO.
Date:
December 24, 2002
Creator:
O'Connor, William K.; Turner, Paul C. & Addison, G.W. (AJT Enterprises, Inc.)
System:
The UNT Digital Library
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
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
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
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
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
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
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
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
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
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
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
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}
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
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
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
Acoustic energy-driven fluid pump and method
Bulk fluid motion is promoted in a gaseous fluid contained within a conduit system provided with a diffuser without the need for a mean pressure differential across the conduit system. The contacting of the gaseous fluid with unsteady energy at a selected frequency and pressure amplitude induces fluid flow through the conical diffuser. The unsteady energy can be provided by pulse combustors, thermoacoustic engines, or acoustic energy generators such as acoustic speakers.
Date:
December 1, 1997
Creator:
Janus, Michael C.; Richards, George A. & Robey, Edward H.
System:
The UNT Digital Library
An arc fault detection system
An arc fault detection system for use on ungrounded or high-resistance-grounded power distribution systems is provided which can be retrofitted outside electrical switchboard circuits having limited space constraints. The system includes a differential current relay that senses a current differential between current flowing from secondary windings located in a current transformer coupled to a power supply side of a switchboard, and a total current induced in secondary windings coupled to a load side of the switchboard. When such a current differential is experienced, a current travels through a operating coil of the differential current relay, which in turn, opens an upstream circuit breaker located between the switchboard and a power supply to remove the supply of power to the switchboard.
Date:
December 1, 1997
Creator:
Jha, Kamal N.
System:
The UNT Digital Library
Combined heat and mass transfer device for improving separation process
A two-phase small channel heat exchange matrix for providing simultaneous heat transfer and mass transfer at a single, predetermined location within a separation column, whereby the thermodynamic efficiency of the separation process is significantly improved. The small channel heat exchange matrix is comprised of a series of channels having a hydraulic diameter no greater than 5.0 mm. The channels are connected to an inlet header for supplying a two-phase coolant to the channels and an outlet header for receiving the coolant horn the channels. In operation, the matrix provides the liquid-vapor contacting surfaces within a separation column, whereby liquid descends along the exterior surfaces of the cooling channels and vapor ascends between adjacent channels within the matrix. Preferably, a perforated and concave sheet connects each channel to an adjacent channel, such that liquid further descends along the concave surfaces of the sheets and the vapor further ascends through the perforations in the sheets. The size and configuration of the small channel heat exchange matrix allows the heat and mass transfer device to be positioned within the separation column, thereby allowing precise control of the local operating conditions within the column and increasing the energy efficiency of the process.
Date:
December 1, 1997
Creator:
Tran, Thanh Nhon
System:
The UNT Digital Library
Constant field gradient planar cavity structure
A cavity structure is described having at least two opposing planar housing members spaced apart to accommodate the passage of a particle beam through the structure between the members. Each of the housing members have a plurality of serially aligned hollows defined therein, and also passages, formed in the members, which interconnect serially adjacent hollows to provide communication between the hollows. The opposing planar housing members are spaced and aligned such that the hollows in one member cooperate with corresponding hollows in the other member to form a plurality of resonant cavities aligned along the particle beam within the cavity structure. To facilitate the obtaining of a constant field gradient within the cavity structure, the passages are configured so as to be incrementally narrower in the direction of travel of the particle beam. In addition, the spacing distance between the opposing housing members is configured to be incrementally smaller in the direction of travel of the beam.
Date:
December 1, 1997
Creator:
Kang, Yoon W. & Kustom, R.L.
System:
The UNT Digital Library