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Multiple-reflection optical gas cell. [DOE Patent Application]

Description: A multiple-reflection optical cell for Raman or fluorescence gas analysis consists of two spherical mirrors positioned transverse to a multiple-pass laser cell in a confronting plane-parallel alignment. The two mirrors are of equal diameter but possess different radii of curvature. The spacing between the mirrors is uniform and less than half of the radius of curvature of either mirror. The mirror of greater curvature possesses a small circular portal in its center which is the effective point … more
Date: June 15, 1981
Creator: Matthews, T.G.
Partner: UNT Libraries Government Documents Department
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Microwave sintering of nanophase ceramics without concomitant grain growth

Description: A method of sintering nanocrystalline material is disclosed wherein the nanocrystalline material is microwaved to heat the material to a temperature less than about 70% of the melting point of the nanocrystalline material expressed in degrees K. This method produces sintered nanocrystalline material having a density greater than about 95% of theoretical and an average grain size not more than about 3 times the average grain size of the nanocrystalline material before sintering. Rutile TiO[sub 2… more
Date: April 15, 1991
Creator: Eastman, J.A.; Sickafus, K.E. & Katz, J.D.
Partner: UNT Libraries Government Documents Department
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Cavity resonance absorption in ultra-high bandwidth CRT deflection structure

Description: An improved ultra-high bandwidth helical coil deflection structure for a cathode ray tube is described comprising a first metal member having a bore therein, the metal walls of which form a first ground plane; a second metal member coaxially mounted in the bore of the first metal member and forming a second ground plane; a helical deflection coil coaxially mounted within the bore between the two ground planes; and a resistive load disposed in one end of the bore and electrically connected to th… more
Date: May 15, 1991
Creator: Dunham, M. E. & Hudson, C. L.
Partner: UNT Libraries Government Documents Department
open access

Microwave Sintering of Nanophase Ceramics Without Concomitant Grain Growth

Description: A method of sintering nanocrystalline material is disclosed wherein the nanocrystalline material is microwaved to heat the material to a temperature less than about 70% of the melting point of the nanocrystalline material expressed in degrees K. This method produces sintered nanocrystalline material having a density greater than about 95% of theoretical and an average grain size not more than about 3 times the average grain size of the nanocrystalline material before sintering. Rutile TiO{sub 2… more
Date: April 15, 1991
Creator: Eastman, Jeffrey A.; Sickafus, Kurt E. & Katz, Joel D.
Partner: UNT Libraries Government Documents Department
open access

Reflection mass spectrometry technique for monitoring and controlling composition during molecular beam epitaxy

Description: This invention is comprised of a method for on-line accurate monitoring and precise control of molecular beam epitaxial growth of Groups III-III-V or Groups III-V-V layers in an advanced semiconductor device incorporates reflection mass spectrometry. The reflection mass spectrometry is responsive to intentional perturbations in molecular fluxes incident on a substrate by accurately measuring the molecular fluxes reflected from the substrate. The reflected flux is extremely sensitive to the stat… more
Date: August 15, 1990
Creator: Brennan, T. M.; Hammons, B. E. & Tsao, J. Y.
Partner: UNT Libraries Government Documents Department
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Catalysts for Conversion of Methane to Higher Hydrocarbons

Description: Catalysts for converting methane to higher hydrocarbons such as ethane and ethylene in the presence of oxygen at temperatures in the range of about 700 to 900{degrees}C are described. These catalysts comprise calcium oxide or gadolinium oxide respectively promoted with about 0.025--0.4 mole and about 0.1--0.7 mole sodium pyrophosphate. A preferred reaction temperature in a range of about 800 to 850{degrees}C with a preferred oxygen-to-methane ratio of about 2:1 provides an essentially constant … more
Date: May 15, 1991
Creator: Siriwardane, Ranjani V.
Partner: UNT Libraries Government Documents Department
open access

Coal Beneficiation by Gas Agglomeration

Description: Coal beneficiation is achieved by suspending coal fines in a colloidal suspension of microscopic gas bubbles in water under atmospheric conditions to form small agglomerates of the fines adhered by the gas bubbles. The agglomerates are separated, recovered and resuspended in water. Thereafter, the pressure on the suspension is increased above atmospheric to deagglomerate, since the gas bubbles are then re-dissolved in the water. During the deagglomeration step, the mineral matter is dispersed, … more
Date: March 15, 2000
Creator: Wheelock, Thomas D. & Shen, Meiyu
Partner: UNT Libraries Government Documents Department
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Apparatus and method for critical current measurements

Description: An apparatus for the measurement of the critical current of a superconductive sample, e.g., a clad superconductive sample, the apparatus including a conductive coil, a means for maintaining the coil in proximity to a superconductive sample, an electrical connection means for passing a low amplitude alternating current through the coil, a cooling means for maintaining the superconductive sample at a preselected temperature, a means for passing a current through the superconductive sample, and, a… more
Date: March 15, 1991
Creator: Martin, J. A. & Dye, R. C.
Partner: UNT Libraries Government Documents Department
open access

Bi-Stable Optical Actuator

Description: 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.
Partner: UNT Libraries Government Documents Department
open access

Pressure Gradient Passivation of Carbonaceous Material Normally Susceptible to Spontaneous Combustion

Description: 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 r… more
Date: July 15, 1999
Creator: Ochs, Thomas L.; Sands, William D.; Schroeder, Karl; Summers, Cathy A. & Utz, Bruce R.
Partner: UNT Libraries Government Documents Department
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