Abstract: A Group IIA metal-Group IIIA metal-silicon substantially homogeneous liquid alkoxide is prepared from a reaction mixture of a Group IIA metal, a Group IIIA metal, a silicon tetraalkoxide, and a liquid defined by the formula ROR' where R is an alkyl group and R' is hydrogen or an alkyl group. The alkoxide can then be hydrolyzed, azeotropically distilled, dried, milled, and calcined to produce a ceramic powder. Advantageously, the ceramic powder can be compacted and sintered at relatively low temperatures which enable it to be used in electrical applications where high sintering temperatures would be deleterious.
Abstract: A method for combusting fuel containing bound nitrogen to achieve reduced NO.sub.x emissions wherein the oxidant and fuel are injected separately into a combustion zone through a burner and the oxidant is injected with a momentum equal to at least three times the fuel stream momentum and at an angle equal to or greater than the sum of the angles of the fuel stream periphery and oxidant stream periphery with their respective centerlines.
Abstract: A refractory sheet member is positioned in a cut-out portion of graphite side and end plates of an aluminum holding and refining vessel to create an effective barrier to the flow of molten aluminum through the channel formed upon the pulling of the plates apart when the vessel is heated to operating temperature.
Abstract: Feed air to a prepurifier adsorption system/cryogenic air separation system for dry, high purity nitrogen and/or oxygen production is dried in a membrane dryer preferably characterized by a countercurrent flow path. Drying is enhanced by the use of purge gas on the permeate side of the membrane dryer, which adsorption system or cryogenic air separation system product or waste gas, dried feed air or ambient air being used as purge gas.
Type:
Grant
Filed:
May 12, 1989
Date of Patent:
June 19, 1990
Assignee:
Union Carbide Corporation
Inventors:
Ravi Prasad, Oscar W. Haas, Harry Cheung
Abstract: High purity nitrogen from an air separation membrane/deoxo system is dried in a membrane dryer unit preferably operated with a countercurrent flow path in the membrane bundle. Drying is enhanced by the use of purge gas on the permeate side of the membrane dryer unit, with feed air, product nitrogen or waste gas from the air separation membrane system being used as purge gas.
Abstract: A process and apparatus for coating a substrate with source material from a solid cathode in a vacuum chamber supplied with a reactive or inert gas at low pressure. An electric arc is generated between an evaporable end surface of the cathode and an anode. An elongated member surrounds the cathode and extends a predetermined minimum distance "X" beyond the evaporable end surface of the cathode to form a cathode chamber. The inert or reactive gas is directed to flow into the cathode chamber before entering the vacuum chamber.
Abstract: A process for producing crystalline silicon nitride powder by a gas phase reaction of ammonia (NH.sub.3) and silane (SiH.sub.4) with a molar ratio of 7:1 or above at a temperature of 900.degree. C. or above and the heating the as-reacted amorphous powders at a temperature of 1350.degree. C. to 1800.degree. C. to convert the powders to a highly pure and submicron crystalline silicon nitride powder comprising at least a 90% .alpha.-Si.sub.3 N.sub.4 phase.
Abstract: A composite sheet suitable for manufacturing thermally insulating gaskets for use between an aluminum head and steel muffler of an internal combustion engine, comprising a thermally insulating refractory fiber layer disposed between a metal layer and a flexible graphite layer.
Abstract: A valve-regulator assembly for rendering a high pressure gas source compatible with lower pressure equipment, said valve-regulator being sealable or remote from the high pressure gas source enabling recharging at high pressure.
Type:
Grant
Filed:
April 14, 1989
Date of Patent:
March 20, 1990
Assignee:
Union Carbide Corporation
Inventors:
Francis E. Pritchard, Vincent J. Kibler
Abstract: A labyrinth seal for sealing the gap between the rotating impeller assembly and the stationary housing of turbomachinery comprising a seal holder which serves simultaneously to comprise the stationary part of the seal and to contact process gas so as to maintain the stationary seal part temperature at about the temperature of the rotating part, thus reducing differential thermal change between the stationary and rotating members of the labyrinth seal.
Abstract: A burner and combustion method employing oxygen or oxygen-enriched air as the oxidant comprising a low velocity oxidant stream in proximity to high velocity main oxidant within a combustion zone enabling efficient combustion with a stable flame at very high oxidant velocities.
Abstract: A process which effectively uses steam produced by a cogeneration facility to cool gas wherein the steam is passed through an absorption chiller to cool water which in turn is used to cool the gas.
Abstract: A valve-regulator assembly for rendering a high pressure gas source compatible with lower pressure equipment, said valve-regulator being sealable or remote from the high pressure gas source enabling recharging at high pressure.
Type:
Grant
Filed:
April 14, 1989
Date of Patent:
March 6, 1990
Assignee:
Union Carbide Corporation
Inventors:
Francis E. Pritchard, Vincent J. Kibler
Abstract: A hot-pressed ceramic composite having good resistance to thermal shock and good erosion/corrosion resistance in molten alloys, and a method for producing said composite which comprises the blending of fused zirconia mullite with boron nitride.
Abstract: Composites of alumina and boron nitride having superior thermal shock resistance, and particularly suitable for use in hot metal applications such as break rings in horizontal continuous casters.
Abstract: A method and apparatus for work expanding a cryogenic liquid wherein the liquid is expanded in a manner to avoid a transient pressure drop below the flash point thus reducing the potential for cavitation and consequent operating inefficiencies.
Abstract: The present invention pertains to a packing structure and method of packing which can be used in the wellbore of injection wells for the recovery of heavy oils, shale oils, and tars, and in well shafts for in-situ coal gasification. The packing can also be used in the wellbore of gas and light oil production wells. The packing is used to provide passive protection of well structural components in the event of a well fire or fire in the formation near the well.The packing is placed in the well shaft below ground level, and preferably below the well packer. The packing particle size, as related to the well casings, is a critical feature of the invention. Particle size distribution, and position of placement of packing in the wellbore as a function of packing particle size, are significant variables which can be tailored to the application.
Abstract: This invention relates to heterogeneous (organic polymer-supported) calcium-containing catalysts and the use thereof in the preparation of alkoxylation products, i.e., condensation reaction products of alkylene oxides and organic compounds having at least one active hydrogen. In another aspect of this invention, processes are provided for preparing heterogeneous (organic polymer-supported) calcium-containing catalysts for alkoxylation using calcium oxide or calcium hydroxide as sources for the catalytically-active calcium. In a further aspect of this invention, alkoxylation products are provided that have beneficial, narrow molecular weight ranges and are essentially neutral in pH and free from catalyst residues.
Abstract: A process for producing ultra high purity nitrogen from nitrogen produced by the cryogenic rectification of air wherein superatomospheric nitrogen is progressively condensed and revaporized to effect rejection of lower boiling impurities without need for additional energy beyond that contained in the nitrogen input.
Abstract: The invention relates to a fuel-oxidant mixture for detonation gun applications comprising an oxidant such as oxygen and a fuel mixture of two combustible gases such as acetylene and propylene. The invention also relates to articles coated in a process using this fuel-oxidant mixture.