Abstract: A method for producing CVD diamond film on a substrate comprised of a hydride-forming metal. The substrate provides for easy release of the CVD diamond coating formed thereon upon exposure to a hydrogen pressure. Self-supporting CVD diamond films of large dimension are easily obtained without dissolving the substrate. The substrate can be used in conventional CVD reactors.

Abstract: Temperature uniformity and control in apparatus for chemical vapor deposition of diamond is improved by contacting the rear of the substrate assembly, which may be a substrate or a holder containing substrates, with a thermal spreader, preferably of copper and preferably having heating means embedded therein or associated therewith. The thermal spreader contacts a thermal resistance unit, preferably of stainless steel, which in turn is in contact with a cooling element that preferably has coolant passages therein.

Abstract: Graphite substrate holders for employment in apparatus for chemical vapor deposition of diamond decrease the tendency of the formed diamond sheets to crack or shatter upon separation from the substrates. Said holders and the substrates therein preferably have rounded edges, to suppress crack formation at sharp corners. The holders are preferably coated, at least in part, with a tie-layer and a hydride-forming metal such as niobium. Also, certain maximum distances between the edges of the holder and substrates are preferably maintained in order to prevent contact of diamond with a heated filament employed for thermal activation.

Abstract: An apparatus for forming a superconductive joint in tape or wire has features which include a closeable vessel with gas inlets for depositing a superconducting layer by chemical vapor deposition, and a form in combination with current clamps and conductive leads to heat a length of tape to a temperature effective to deposit a superconductive coating thereon. Preferably, the form and associated structure are unitary with a base plate which seals the vessel.

Abstract: Superconducting joints between superconducting tape ends are produced by a series of operations which includes stripping non-superconductive material from the tape ends, joining them with a conductive coating and depositing a superconductive alloy layer thereon, typically of triniobium tin, by a chemical vapor deposition reaction of hydrogen with the corresponding metal halides. Certain of the steps are performed in an inert atmosphere free from moisture, elemental hydrogen and elemental oxygen, typically a helium atmosphere.

Abstract: A battery exposed to heating from incident sunlight is cooled by rejecting heat to air drawn through a chimney by the heating of at least portions of the chimney by the incident sunlight. The battery is placed within the chimney so that the air flow in the chimney passes around the battery, enabling heat to be transferred directly from the battery to the air. Air flow in the chimney is generated by sunlight incident on the exterior of the chimney, causing heating of air within at least a portion of the chimney to create a natural convective air flow within the chimney, with relatively cool outside ambient air being drawn in at one end of the chimney and heated air being exhausted out the other end of the chimney.

Abstract: A microporous plug is provided which serves to seal a vessel so as to prevent the bulk flow of gases through an outlet. The pores of said microporous plug are sized so as to permit the transport of gases to and from the vessel interior by Knudsen diffusion. In preferred embodiments, the pores of the plug are sized so as to release helium from the interior of a vessel and restrict the transport of carbon dioxide into the vessel from the surrounding atmosphere by Knudsen diffusion. Such embodiments are particularly useful on Mars where the helium is transported into an environment of higher pressure. In other embodiments, the microporous plug is used in conjunction with an absorber positioned within the vessel to react with atmospheric gases that pass through the plug, such as carbon dioxide. Also provided are radioisotope thermoelectric generators that incorporate a microporous plug and optionally an absorber.

Abstract: A method is provided for determining the stoichiometric end point of phosgenation reactions which produce polycarbonates and chloroformates, respectively, by monitoring the rate of heat generated by the reaction mixture per unit of phosgene utilized.

Abstract: A method is provided for making reaction products of phosgene and dihydric phenol under interfacial reaction conditions. The dihydric phenol such as BPA is introduced into the reactor in the form of a stable suspension which reduces phosgene hydrolysis, minimizes phosgene escape and effects improved BPA metering into the reactor.

Abstract: A method is provided for determining the stoichiometric end point of phosgenation reactions which produce polycarbonates and chloroformates, respectively, by monitoring the rate of heat generated by the reaction mixture per unit of phosgene utilized.

Abstract: A method is provided for reducing the reflux temperatures of methylene chloride in phosgenation reactions by introducing a second inert vaporizable component to the reaction medium. This second inert vaporizable component has a lower vaporization temperature than the methylene chloride so as to reduce the temperature of vaporization of the mixture. More efficient use of phosgene is obtained when polymerizing aromatic dihydroxy compounds to polycarbonates and higher yields of monomeric and dimeric bischloroformates are obtained.

Abstract: The molecular weight of linear polyesters such as poly(butylene terephthalate) and poly(ethylene terephthalate), especially the former, is increased by contacting a polyester having a maximum particle diameter of 1.0 and preferably 0.5 mm., with a mixture of an inert gas and an aliphatic diol such as 1,4-butanediol in the gaseous state at a temperature about 5.degree.-15.degree. C. below its equilibrium melting temperature, at a diol partial pressure of about 0.1-10 torr, to reduce the proportion of acid end groups; and subjecting the product thus obtained to solid state polymerization under vacuum. By this method, polyesters having a number average molecular weight of at least 100,000, useful for blow molding and the like, can be obtained.

Abstract: Catalyst for the production of methane from carbon and/or coal by means of catalytic gasification. The catalyst compostion containing at least two alkali metal salts. A particulate carbonaceous substrate or carrier is used.

Abstract: In the preparation of the gaseous reactant feed to undergo a chemical reaction requiring the presence of steam, the efficiency of overall power utilization is improved by premixing the gaseous reactant feed with water and then heating to evaporate the water in the presence of the gaseous reactant feed, the heating fluid utilized being at a temperature below the boiling point of water at the pressure in the volume where the evaporation occurs.

Abstract: A vaporization cooled transformer includes an improved liquid distribution system which distributes the dielectric or cooling liquid in a predetermined fashion for liquid film flow over the wall surfaces of vertical cooling ducts with minimal liquid hold-up.