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1,984 Matching Results
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Hydrocracking and hydroisomerization of long-chain alkanes and polyolefins over metal-promoted anion-modified transition metal oxides
A method is described for cracking a feedstock by contacting the feedstock with a metal-promoted anion-modified metal oxide catalyst in the presence of hydrogen gas. The metal oxide of the catalyst is one or more of ZrO{sub 2}, HfO{sub 2}, TiO{sub 2} and SnO{sub 2}, and the feedstock is principally chains of at least 20 carbon atoms. The metal-promoted anion-modified metal oxide catalyst contains one or more of Pt, Ni, Pd, Rh, Ir, Ru, (Mn and Fe) or mixtures of them present between about 0.2% to about 15% by weight of the catalyst. The metal-promoted anion-modified metal oxide catalyst contains one or more of SO{sub 4}, WO{sub 3}, or mixtures of them present between about 0.5% to about 20% by weight of the catalyst.
Date:
December 1996
Creator:
Venkatesh, Koppampatti R.; Hu, Jianli; Tierney, John W. & Wender, Irving
System:
The UNT Digital Library
Light gas gun with reduced timing jitter
A gas gun having a prepressurized projectile held in place with a glass rod in compression is described. The glass rod is destroyed with an explosive at a precise time which allows a restraining pin to be moved by pneumatic means and free the projectile.
Date:
December 1, 1996
Creator:
Laabs, Gary W.; Funk, David J. & Asay, Blaine W.
System:
The UNT Digital Library
Method for the photocatalytic conversion of methane
The invention relates to a method for converting methane and water to methanol and hydrogen using visible light and a catalyst.
Date:
December 1996
Creator:
Noceti, R. P.; Taylor, C. E. & D'Este, J. R.
System:
The UNT Digital Library
Multilayered nuclear fuel element
A nuclear fuel element is described which is suitable for high temperature applications comprised of a kernel of fissile material overlaid with concentric layers of impervious graphite, vitreous carbon, pyrolytic carbon and metal carbide. The kernel of fissile material is surrounded by a layer of impervious graphite. The layer of impervious graphite is then surrounded by a layer of vitreous carbon. Finally, an outer shell which includes alternating layers of pyrolytic carbon and metal carbide surrounds the layer of vitreous carbon.
Date:
December 1, 1996
Creator:
Schweitzer, Donald G. & Sastre, Cesar
System:
The UNT Digital Library
Porous desulfurization sorbent pellets containing a reactive metal oxide and an inert zirconium compound
Sorbent pellets for removing hydrogen sulfide from coal gas are prepared by combining a reactive oxide, in particular zinc oxide, with a zirconium compound such as an oxide, silicate, or aluminate of zirconium, and an inorganic binder and pelletizing and calcining the mixture. Alternately, the zinc oxide may be replaced by copper oxide or a combination of copper, molybdenum, and manganese oxides. The pellet components may be mixed in dry form, moistened to produce a paste, and converted to pellets by forming an aqueous slurry of the components and spray drying the slurry, or the reactive oxide may be formed on existing zirconium-containing catalyst-carrier pellets by infusing a solution of a salt of the active metal onto the existing pellets and firing at a high temperature to produce the oxide. Pellets made according to this invention show a high reactivity with hydrogen sulfide and durability such as to be useful over repeated cycles of sorption and regeneration.
Date:
December 1, 1996
Creator:
Gardner, Todd H. & Gasper-Galvin, Lee D.
System:
The UNT Digital Library
Automatic feature detection and identification in digital point-ordered signals
A computer-based automated method to detect and identify features in digital point-ordered signals. The method is used for processing of non-destructive test signals, such as eddy current signals obtained from calibration standards. The signals are first automatically processed to remove noise and to determine a baseline. Next, features are detected in the signals using mathematical morphology filters. Finally, verification of the features is made using an expert system of pattern recognition methods and geometric criteria. The method has the advantage that standard features can be located without prior knowledge of the number or sequence of the features. Further advantages are that standard features can be differentiated from irrelevant signals features such as noise, and detected features are automatically verified by parameters extracted from the signals. The method proceeds fully automatically without initial operator set-up and without subjective operator feature judgment.
Date:
December 31, 1995
Creator:
Oppenlander, Jane E.; Loomis, Kent C.; Brudnoy, David M. & Levy, Arthur J.
System:
The UNT Digital Library
CAM operated tool for proximate or remote holding of an object
A tool for releasably holding an object includes a receptacle having an outer sleeve and a rotatable inner sleeve. The inner sleeve is coaxially positioned within the outer sleeve and includes a locking member. An insert which is adapted to be operably associated with the receptacle includes a cam. The cam includes a guide and a slot so that when the cam is inserted into the inner sleeve, the guide aligns the locking member with the slot allowing the locking member to engage the slot thereby holding the receptacle and the insert together.
Date:
December 31, 1995
Creator:
Schrum, P.B. & Gajdzik, G.P. Jr.
System:
The UNT Digital Library
Compound semiconductor field-effect transistors with improved dc and high frequency performance
A method for making compound semiconductor devices including the use of a p-type dopant is disclosed wherein the dopant is co-implanted with an n-type donor species at the time the n-channel is deposited. Also disclosed are devices manufactured using the method. In the preferred embodiment n-MESFETs and other similar field effect transistor devices are manufactured using C ions implanted with Si atoms in GaAs to form an n-channel. C exhibits a unique characteristic in the context of the invention in that it exhibits a low activation efficiency (typically, 50% or less) as a p-type dopant, and consequently, it acts to sharpen the Si n-channel by compensating Si donors in the region the Si-channel tail, but does not contribute substantially to the acceptor concentration in the region of the buried p-implant. As a result, the invention provides for improved field effect transistor devices with enhancement of both DC and high-frequency performance.
Date:
December 31, 1995
Creator:
Zolper, J. C.; Sherwin, M. E. & Baca, A. G.
System:
The UNT Digital Library
Deconnable self-reading pocket dosimeter containment with self-contained light
A container for a self-reading pocket dosimeter includes a transparent tube for receiving the self-reading pocket dosimeter, a light source mounted at one end of the transparent tube, and an eyepiece mounted on an opposite end of the transparent tube for viewing a read-out of the self-reading pocket dosimeter. The container may further include an activation device for selectively supplying power to the light source. The container both protects the dosimeter from being contaminated and provides a light source for viewing the dosimeter.
Date:
December 31, 1995
Creator:
Stevens, R. L.; Arnold, G. N. & McBride, R. G.
System:
The UNT Digital Library
Device and method for remotely venting a container
Numerous incidents of fire, explosion, and ground contamination have occurred at various facilities over the last several years due to drum rupture on account of overpressurization. These incidents frequently are caused by an ignition source or a reaction between incompatible materials. The incidents may also occur simply as a result of climatic changes causing the drum to be over pressurized. A device for venting a container having a bung includes a saddle assembly securable to a container and having a support extending therefrom. A first arm is rotatably secured to the support, and the first arm extends in a first direction. A second arm has a first end portion drivingly engaged with the first arm, so that rotation of the first arm causes rotation of the second arm. A second end portion of the first arm is positionable proximate the bung of the container. A socket is operably associated and rotatable with the second end portion and is drivingly engageable with the bung, so that rotation of the socket causes corresponding rotation of the bung for thereby venting the container.
Date:
December 31, 1995
Creator:
Vodila, J. M. & Bergersen, J. A.
System:
The UNT Digital Library
Dual-keel electrodynamic maglev system
A propulsion and stabilization system with a plurality of superconducting magnetic devices affixed to the dual-keels of a vehicle, where the superconducting magnetic devices produce a magnetic field when energized. The system also includes a plurality of figure-eight shaped null-flux coils affixed to opposing vertical sides of slots in a guideway. The figure-eight shaped null-flux coils are vertically oriented, laterally cross-connected in parallel, longitudinally connected in series, and continue the length of the vertical slots providing levitation and guidance force. An external power source energizes the figure-eight shaped null-flux coils to create a magnetic traveling wave that interacts with the magnetic field produced by the superconducting magnets to impart motion to the vehicle.
Date:
December 31, 1995
Creator:
He, J.; Wang, Z.; Rote, D. M.; Coffey, H. T.; Hull, J. R.; Mulcahy, T. M. et al.
System:
The UNT Digital Library
Durable regenerable sorbent pellets for removal of hydrogen sulfide from coal gas
Pellets for removing hydrogen sulfide from a coal gasification stream at an elevated temperature are presented in durable form, usable over repeated cycles of absorption and regeneration. The pellets include a material reactive with hydrogen sulfide, in particular zinc oxide, a binder, and an inert material, in particular calcium sulfate (Drierite), having a particle size substantially larger than other components of the pellets. A second inert material and a promoter may also be included. Preparation of the pellets may be carried out by dry, solid-state mixing of components, moistening the mixture, and agglomerating it into pellets, followed by drying and calcining. Pellet size is selected, depending on the type of reaction bed for which the pellets are intended. The use of inert material with a large particle size provides a stable pellet structure with increased porosity, enabling effective gas contact and prolonged mechanical durability.
Date:
December 31, 1995
Creator:
Siriwardane, R.V.
System:
The UNT Digital Library
Electronically shielded solid state charged particle detector
An electronically shielded solid state charged particle detector system having enhanced radio frequency interference immunity includes a detector housing with a detector entrance opening for receiving the charged particles. A charged particle detector having an active surface is disposed within the housing. The active surface faces toward the detector entrance opening for providing electrical signals representative of the received charged particles when the received charged particles are applied to the active surface. A conductive layer is disposed upon the active surface. In a preferred embodiment, a nonconductive layer is disposed between the conductive layer and the active surface. The conductive layer is electrically coupled to the detector housing to provide a substantially continuous conductive electrical shield surrounding the active surface. The inner surface of the detector housing is supplemented with a radio frequency absorbing material such as ferrite.
Date:
December 31, 1995
Creator:
Balmer, David K.; Haverty, Thomas W.; Nordin, Carl W. & Tyree, William H.
System:
The UNT Digital Library
Electrorefining cell with parallel electrode/concentric cylinder cathode
A cathode-anode arrangement for use in an electrolytic cell is adapted for electrochemically refining spent nuclear fuel from a nuclear reactor and recovering purified uranium and a mixture of uranium and plutonium for use as a fresh blanket and core fuel in a nuclear reactor. The arrangement includes a plurality of inner anodic dissolution baskets that are each attached to a respective support rod, are submerged in a molten lithium halide salt, and are rotationally displaced. An inner hollow cylindrical-shaped cathode is concentrically disposed about the inner anodic dissolution baskets. Concentrically disposed about the inner cathode in a spaced manner are a plurality of outer anodic dissolution baskets, while an outer hollow cylindrical-shaped cathode is disposed about the outer anodic dissolution baskets. Uranium is deposited from the anode baskets in a uniform cylindrical shape on the inner and outer cathode cylinders by rotating the anode baskets within the molten lithium halide salt. Scrapers located on each anode basket abrade and remove the spent fuel deposits on the surfaces of the inner and outer cathode cylinders, with the spent fuel falling to the bottom of the cell for removal. Cell resistance is reduced and uranium collection efficiency enhanced by increasing the …
Date:
December 31, 1995
Creator:
Gay, E. C.; Miller, W. E. & Laidler, J. J.
System:
The UNT Digital Library
Fast superconducting magnetic field switch
The superconducting magnetic switch or fast kicker magnet is employed with an electron stream or a bunch of electrons to rapidly change the direction of flow of the electron stream or bunch of electrons. The apparatus employs a beam tube which is coated with a film of superconducting material. The tube is cooled to a temperature below the superconducting transition temperature and is subjected to a constant magnetic field which is produced by an external dc magnet. The magnetic field produced by the dc magnet is less than the critical field for the superconducting material, thus, creating a Meissner Effect condition. A controllable fast electromagnet is used to provide a magnetic field which supplements that of the dc magnet so that when the fast magnet is energized the combined magnetic field is now greater than the critical field and the superconducting material returns to its normal state allowing the magnetic field to penetrate the tube. This produces an internal field which effects the direction of motion and of the electron stream or electron bunch. The switch can also operate as a switching mechanism for charged particles. Magnetic switches and particularly fast kicker magnets are used in the accelerator industry to …
Date:
December 31, 1995
Creator:
Goren, Y. & Mahale, N.K.
System:
The UNT Digital Library
Fiber optic assembly and method of making same
There is provided an assembly having a light guiding medium sealed to a holder. Preferably the holder is a metal shell and a light guiding medium is an optical fiber of glass or sapphire whisker. The assembly includes a sealing medium which sealingly engages the metal holder to the fiber. In the formation of the assembly, the seal is essentially hermetic having a capability of minimizing leakage having a helium leak rate of less than 1 {times} 10{sup {minus}8} cubic centimeters per second and high strength having a capability of withstanding pressures of 100,000 psi or greater. The features of the assembly are obtained by a specific preparation method and by selection of specific starting materials. The fiber is selected to have a sufficiently high coefficient of thermal expansion which minimizes strains in the component during fabrication, as a result of fabrication, and during use. The other components are selected to be of a material having compatible coefficients of thermal expansion (TEC) where the TEC of the holder is greater than or equal to the TEC of the sealing material. The TEC of the sealing material is in turn greater than or equal to the TEC of the fiber. It …
Date:
December 31, 1995
Creator:
Kramer, Daniel P. & Beckman, Thomas M.
System:
The UNT Digital Library
A flow injection trace gas analyzer for on-site determination of organoarsenicals
Lewisite was developed during World War I as a chemical warfare agent. Several countries produced large quantities of the agent before, during and after World War II. The Chemical Weapons Convention treaty, recently signed, requires the destruction of Lewisite. In implementing the Chemical Weapons Convention treaty, it will be necessary to monitor the facilities at which various chemical agents including Lewisite may be stored for compliance with the agreement. The inspection procedures must meet stringent standards for safety, quality assurance and accountability. In preparing for these inspections a technology gap has been identified in the ability to detect and monitor for the presence of Lewisite in ambient air, particularly in the facilities where chemical warfare agents are stored. A method and an apparatus for determining the concentration of Lewisite in the ambient atmosphere are described. The apparatus includes a mechanism for separating and collecting a Lewisite sample from the atmosphere, a mechanism for converting the collected Lewisite to an arsenite ion solution sample, and a mechanism for electrochemically detecting the converted arsenite ions in the sample, whereby the amount of arsenite ions detected is proportional to the concentration of Lewisite in the atmosphere.
Date:
December 31, 1995
Creator:
Aldstadt, J.H. III
System:
The UNT Digital Library
High-gradient compact linear accelerator
A high-gradient linear accelerator comprises a solid-state stack in a vacuum of five sets of disc-shaped Blumlein modules each having a center hole through which particles are sequentially accelerated. Each Blumlein module is a sandwich of two outer conductive plates that bracket an inner conductive plate positioned between two dielectric plates with different thicknesses and dielectric constants. A third dielectric core in the shape of a hollow cylinder forms a casing down the series of center holes, and it has a dielectric constant different that the two dielectric plates that sandwich the inner conductive plate. In operation, all the inner conductive plates are charged to the same DC potential relative to the outer conductive plates. Next, all the inner conductive plates are simultaneously shorted to the outer conductive plates at the outer diameters. The signal short will propagate to the inner diameters at two different rates in each Blumlein module. A faster wave propagates quicker to the third dielectric core across the dielectric plates with the closer spacing and lower dielectric constant. When the faster wave reaches the inner extents of the outer and inner conductive plates, it reflects back outward and reverses the field in that segment of the …
Date:
December 31, 1995
Creator:
Carder, B. M.
System:
The UNT Digital Library
In-situ emplacement and densification of geomaterials for sealing applications
A method and apparatus are described for forming improved seals in boreholes formed in host rock by using the apparatus to introduce a feedstock into the borehole and simultaneously subject the introduced feedstock to both compressive and shear stresses until the borehole becomes filled and sealed. These seals are primarily intended to restrict the movement of radioactive or hazardous materials into the accessible environment.
Date:
December 31, 1995
Creator:
Finley, Ray E. & Zeuch, David H.
System:
The UNT Digital Library
Installation and assembly device and method of using
The present invention relates to an installation and assembly device and method for facilitating the fitup of mating components during blind or remote installation and assembly, especially where close fitup tolerances are involved. The present invention is particularly useful for the purpose of facilitating vertical and/or radial relative positioning of a pump impeller within a mating inlet nozzle during a blind assembly wherein actual fitup cannot be observed during installation. The information within identifies just one successful application of the installation and assembly alignment device for a pump. The device, however, is not solely limited to pump assembly but can be used in other cases where fitup of a sleeve inside a mating bore is required under conditions of close tolerance during a blind or remote assembly. The device is likewise not limited to circular configurations but can be used for many other shapes or configurations. Any material that can be machined and hold reasonably close tolerances can be used for the device. Also, because the sleeve position is adjusted by set screws or bolts, the concentricity can be radially biased, if required, to achieve particular alignment conditions.
Date:
December 31, 1995
Creator:
Kolsun, G.J.
System:
The UNT Digital Library
Leak test adapter for containers
An adapter is provided for facilitating the charging of containers and leak testing penetration areas. The adapter comprises an adapter body and stem which are secured to the container`s penetration areas. The container is then pressurized with a tracer gas. Manipulating the adapter stem installs a penetration plug allowing the adapter to be removed and the penetration to be leak tested with a mass spectrometer. Additionally, a method is provided for using the adapter. The present invention relates generally to leak test adapters, and more particularly to leak test adapters used with containers such as radioactive material shipping containers.
Date:
December 31, 1995
Creator:
Hallett, B.H. & Hartley, M.S.
System:
The UNT Digital Library
Low-temperature hermetic sealing of optical fiber components
A method for manufacturing low-temperature hermetically sealed optical fiber components is provided. The method comprises the steps of: inserting an optical fiber into a housing, the optical fiber having a glass core, a glass cladding and a protective buffer layer disposed around the core and cladding; heating the housing to a predetermined temperature, the predetermined temperature being below a melting point for the protective buffer layer and above a melting point of a solder; placing the solder in communication with the heated housing to allow the solder to form an eutectic and thereby fill a gap between the interior of the housing and the optical fiber; and cooling the housing to allow the solder to form a hermetic compression seal between the housing and the optical fiber.
Date:
December 31, 1995
Creator:
Kramer, Daniel P.
System:
The UNT Digital Library
Method and Apparatus for Reading Meters From a Video Image
A method and system enable acquisition of data about an environment from one or more meters using video images. One or more meters are imaged by a video camera and the video signal is digitized. Then, each region of the digital image which corresponds to the indicator of the meter is calibrated and the video signal is analyzed to determine the value indicated by each meter indicator. Finally, from the value indicated by each meter indicator in the calibrated region, a meter reading is generated. The method and system offer the advantages of automatic data collection in a relatively non-intrusive manner without making any complicated or expensive electronic connections, and without requiring intensive manpower.
Date:
December 31, 1995
Creator:
Lewis, Trevor J. & Ferguson, Jeffrey J.
System:
The UNT Digital Library
A method and system including a double rotary kiln pyrolysis or gasification of waste material
A method is described for destructively distilling an organic material in particulate form wherein the particulates are introduced through an inlet into one end of an inner rotating kiln ganged to and coaxial with an outer rotating kiln. The inner and outer kilns define a cylindrical annular space with the inlet being positioned in registry with the axis of rotation of the ganged kilns. During operation, the temperature of the wall of the inner rotary kiln at the inlet is not less than about 500 C to heat the particulate material to a temperature in the range of from about 200 C to about 900 C in a pyrolyzing atmosphere to reduce the particulate material as it moves from the one end toward the other end. The reduced particulates including char are transferred to the annular space between the inner and the outer rotating kilns near the other end of the inner rotating kiln and moved longitudinally in the annular space from near the other end toward the one end in the presence of oxygen to combust the char at an elevated temperature to produce a waste material including ash. Also, heat is provided which is transferred to the inner …
Date:
December 31, 1995
Creator:
McIntosh, M.J. & Arzoumanidis, G.G.
System:
The UNT Digital Library