Abstract: Tubular solid-state membrane modules for separating oxygen from an oxygen-containing gaseous mixture which provide improved pneumatic and structural integrity and ease of manifolding. The modules are formed from a plurality of tubular membrane units, each membrane unit which comprises a channel-free porous support having connected through porosity which is in contact with a contiguous dense mixed conducting oxide layer having no connected through porosity. The dense mixed conducting oxide layer is placed in flow communication with the oxygen-containing gaseous mixture to be separated and the channel-free porous support of each membrane unit is placed in flow communication with one or more manifolds or conduits for discharging oxygen which has been separated from the oxygen-containing gaseous mixture by permeation through the dense mixed conducting oxide layer of each membrane unit and passage into the manifolds or conduits via the channel-free porous support of each membrane unit.

Abstract: The present invention relates to surface catalyzed ion transport membranes which demonstrate superior oxygen flux. The membranes comprise a dense multicomponent metallic oxide layer having a first surface and a second surface wherein the first surface is coated with a catalyst such as a metal or an oxide of a metal selected from Groups II, V, VI, VII, VIII, IX, X, XI, XV and the F Block lanthanides of the Periodic Table of the Elements. One or more porous layers formed from a mixed conducting multicomponent metallic oxide or a material which is not mixed conducting under process operating conditions may be formed contiguous to the second surface of the dense layer. The claimed membranes are capable of separating oxygen from oxygen-containing gaseous mixtures.

Abstract: The present invention relates to surface catalyzed ion transport membranes which demonstrate superior oxygen flux. The membranes comprise a porous mixed conducting multicomponent metallic oxide layer having a first surface onto which a catalyst is deposited and a second surface which is contiguous with a dense mixed conducting multicomponent metallic oxide layer. Suitable catalysts to be deposited onto the porous mixed conducting layer include one or more metals or oxides of metals selected from Groups II, V, VI, VII, VIII, IX, X, XI, XV and the F Block lanthanides of the Periodic Table of the Elements. The claimed membranes are capable of separating oxygen from oxygen-containing gaseous mixtures.

Abstract: The present invention is a method for manufacturing inorganic membranes which are capable of separating oxygen from air. The membranes comprise a thin layer of a multicomponent metallic oxide which has been deposited onto a porous substrate by organometallic chemical vapor deposition. The inorganic membranes are formed by reacting organometallic complexes corresponding to each of the respective metals making up the multicomponent metallic oxide and an oxidizing agent under conditions sufficient to deposit a thin layer of the multicomponent metallic oxide onto the porous substrate.

Abstract: A coated carbon body having improved resistance to high temperature oxidation and a method for producing the coated carbon body are described. The coated carbon body comprises a carbon body, an intermediate glass forming coating within said converted layer, and an outer refractory coating on the intermediate coating. The body has a converted porous layer formed by etching and reacting the body with gaseous boron oxide and the resulting converted layer contains interconnecting interstices and boron carbide formed by the reaction of the boron oxide and the carbon body. The method comprises contacting a carbon body with boron oxide at an elevated temperature sufficient to cause the reaction between the carbon body and boron oxide to form a converted porous layer which contains interconnecting interstices in the body and boron carbide and then applying the intermediate glass forming coating over the converted layer and an outer refractory coating over the intermediate coating.

Abstract: The present invention is a method for manufacturing inorganic membranes which are capable of separating oxygen from air. The membranes comprise a thin layer of a multicomponent metallic oxide which has been deposited onto a porous substrate by organometallic chemical vapor deposition. The inorganic membranes are formed by reacting organometallic complexes corresponding to each of the respective metals making up the multicomponent metallic oxide and an oxidizing agent under conditions sufficient to deposit a thin layer of the multicomponent metallic oxide onto the porous substrate.

Abstract: The present invention is a method for manufacturing inorganic membranes which are capable of separating oxygen from oxygen-containing gaseous mixtures. The membranes comprise a porous composite of a thin layer of a multicomponent metallic oxide which has been deposited onto a porous support wherein the pores of the multicomponent metallic oxide layer are subsequently filled or plugged with a metallic-based species. The inorganic membranes are formed by depositing a porous multicomponent metallic oxide layer onto the porous support to form a porous composite having a network of pores capable of transporting gases. The network of pores are plugged or filled by organometallic vapor infiltration to form an inorganic membrane having essentially no through porosity.

Abstract: A method for producing a protective coating on the surface of a carbonaceous substrate is described. A substantially uniform coating of a liquid or solid precursor material is provided on the surface of the substrate. The precursor material is one which has boron-oxygen bonds and is substantially non-reactive with the substrate at a first relatively low temperature and is capable of reacting with the substrate at a second temperature which is substantially higher than the first temperature. The substrate is then raised to the second temperature to react the coating with the substrate to form a porous region of substantially uniform depth in the substrate surface. This region contains interconnecting interstices and boron carbide. The interconnecting interstices are then at least partially filled with a glass forming material such as boron, boron oxide, boron carbide, silicon, silicon alloy, silicon dioxide, silicon nitride, silicon oxynitride, germania, and mixtures thereof.

Abstract: Novel volatile barium complexes are disclosed which are very stable and evaporate cleanly at elevated temperatures. Such complexes are highly suited for use as a barium source in OMCVD processes.

Abstract: A coated carbon body having improved resistance to high temperature oxidation and a method for producing the coated carbon body are described. The coated carbon body comprises a carbon body, an intermediate glass forming coating within said converted layer, and an outer refractory coating on the intermediate coating. The body has a converted porous layer formed by etching and reacting the body with gaseous boron oxide and the resulting converted layer contains interconnecting interstices and boron carbide formed by the reaction of the boron oxide and the carbon body. The method comprises contacting a carbon body with boron oxide at an elevated temperature sufficient to cause the reaction between the carbon body and boron oxide to form a converted porous layer which contains interconnecting interstices in the body and boron carbide and then applying the intermediate glass forming coating over the converted layer and an outer refractory coating over the intermediate coating.

Abstract: A coated carbon body having improved resistance to high temperature oxidation and a method for producing the coated carbon body are described. The coated carbon body comprises a carbon body, an intermediate glass forming coating and an outer refractory coating on the intermediate coating. The body has a converted porous layer formed by etching and reacting the body with boron oxide and the resulting converted layer contains interconnecting interstices and boron carbide formed by the reaction of the boron oxide and the carbon body. The method comprises contacting a carbon body with boron oxide at an elevated temperature sufficient to cause the reaction between the carbon body and boron oxide to form a converted porous layer which contains interconnecting interstices in the body and boron carbide and then applying the glass forming coating over the converted layer. Preferably an outer refractory coating is applied over the glass forming coating.

Abstract: An extremely hard, fine grained tungsten carbide produced by thermochemical deposition is described. The tungsten carbide consists primarily of substantially pure tungsten carbide wherein the tungsten carbide consists of WC.sub.1-x, where x is 0 to about 0.4. The disclosed tungsten carbide is free of columnar grains and consists essentially of extremely fine, equiaxial crystals. Also disclosed is a method of producing the disclosed material.

Abstract: An improved method is provided for depositing a thin copper aluminum alloy film on a patterned silicon substrate. A copper base layer conforming to the existing pattern is initially formed on the surface of the substrate, followed by contact with vapors of an aminealane compound, which causes aluminum to be selectively deposited on the copper base layer portion of the substrate. Preferably, copper is applied to a diffusion barrier surface such as tungsten using chemical vapor deposition from a complex of copper (I) perfluoroalkyl-.beta.-diketonate and an olefin or silylolefin. The entire process of developing an alloy film can be carried out without exceeding 200.degree. C.

Abstract: The invention is a process for recovering oxygen from an oxygen-containing gaseous mixture containing one or more components selected from water, carbon dioxide or a volatile hydrocarbon which process utilizes ion transport membranes comprising a multicomponent metallic oxide containing barium. The process utilizes a temperature regime which overcomes problems associated with degradation of barium-containing multicomponent oxides caused by carbon dioxide.

Abstract: The invention is a process for recovering oxygen from an oxygen-containing gaseous mixture containing one or more components selected from water, carbon dioxide or a volatile hydrocarbon which process utilizes ion transport membranes comprising a multicomponent metallic oxide containing strontium, calcium or magnesium. The process utilizes a temperature regime which overcomes problems associated with degradation of strontium-, calcium- and magnesium-containing multicomponent oxides caused by carbon dioxide.

Abstract: A method for heat treating a coated substrate is described wherein the outer coating on the substrate is comprised of a chemically vapor deposited mixture of tungsten and tungsten carbide. The coated substrate is heated to the deposition temperature or not substantially above the deposition temperature in a non-reactive atmosphere. The heat treating temperature is sufficient to confer a desired improvement in erosive and abrasive wear resistance in the outer coating but does not result in substantial degradation of the mechanical properties of the substrate or in formation of undesirable inter-metallic layers.

Abstract: A structural article for high temperature applications comprises a body formed of at least partially consolidated, particulate silicon nitride, a conformal outer coating of silicon nitride or silicon carbide on the body, and a conformal intermediate layer of a silicon, oxygen and nitrogen-containing compound, i.e. silicon oxynitride, chemically bonded to both the body and the outer coating. The method for making such an article comprises providing a body formed of at least partially consolidated, particulate silicon nitride, oxidizing the surface of the body, removing silicon dioxide from the oxidized surface of the body; and chemically vapor depositing a conformal outer coating of silicon nitride or silicon carbide. The conformal outer coating provides a protective envelope around and assists in high temperature isostatic pressing of the body and hence permits one to use the structural article in isostatic pressing processes.

Abstract: This invention relates to a process for restoring permeance of an oxygen-permeable ion transport membrane utilized to recover oxygen from an oxygen-containing gaseous mixture which contains water, carbon dioxide or volatile hydrocarbons. The process utilizes a class of ion transport membranes formed from multicomponent metallic oxides wherein permeance of such membranes had been believed to be permanently degraded by water and the like under conventional process operating temperatures. This invention provides a continuous process for restoring oxygen permeance of such membranes caused by deleterious interaction between the membrane and components such as carbon dioxide, water or hydrocarbons at elevated process temperatures.

Abstract: A method for depositing a thick, adherent and coherent polycrystalline diamond (PCD) film onto a metallic substrate using a deposition rate of no greater than 0.4 .mu.m per hour. The resulting PCD Film has a smooth surface finish, enhanced crystal orientation in comparision to industrial grade diamond powder particularly in the (220) and (400) directions, and excellent electrical and thermal properties. The method enables one to deposit PCD films having a thickness of at least 12 microns for applications on flat as well as curved substrates having wide use in the electronics industry. Thick PCD films of this invention have been found to be ideal for dissipating heat from radio frequency (RF) and microwave (MW) devices.

Abstract: A thick, adherent and coherent polycrystalline diamond (PCD) coated substrate product is disclosed which comprises either a metallic or ceramic substrate and a plurality of separately deposited PCD layers of substantially uniform microstructure and having high electrical resistivity. The method for depositing multi-layers of PCD film onto the substrate comprises chemically depositing at least two separate polycrystalline diamond layers onto the substrate deposition conditions which are substantially different between cycles. The method enables one to deposit PCD films having a thickness of at least 12 microns for applications on flat as well as curved substrates having wide use in the electronics industry. Thick PCT films of this invention have been found to be ideal for dissipating heat from radio frequency (RF) and microwave (MW) devices.