Abstract: Synthetic diamond crystals and films are deposited on a pair of uniformly spaced apart facing plates made of silicon, molybdenum or boron in elemental, nitride or carbide form. The plates are suitably supported within a totally thermally insulated chamber where a pressure of about 10 torr or less is maintained in the form of an atmosphere which includes a carbon source and a major portion of hydrogen, and preferably includes oxygen in equal amount to the carbon. By supplying sufficient microwave power to create a plasma and a uniform temperature of about 950.degree. C. at the plate surfaces, diamond crystals economically grow on the surfaces of the facing plates. Preferably, either the plates or the backing sections thereof have a relatively high thermal conductivity so as to maintain a uniform temperature across the entire plate surface areas.

Abstract: The present invention is related to a composition and methods for producing highly pure, high temperature superconducting materials having the general formula MBa.sub.2 Cu.sub.3 O.sub.7-x, where M is yttrium or a rare earth element and x is from 0 to 0.5. The superconducting material is produced by first obtaining a solution of yttrium or rare earth element and copper. Next a solution of barium is obtained. The two solutions are heated and mixed together forming a precursor precipitate of the superconducting material. Subsequently, in one embodiment of the invention, the precipitate is recovered, calcined, sintered and slow cooled in oxygen or air. This produces a material having a desirable orthorhomic structure which is superconductive at high temperatures.Because no organic solvents are used and no pH control other than the amount of barium in the solution is employed, it is possible to provide a highly pure superconducting material.

Abstract: The first wall of a deuterium-tritium fusion reactor is regenerated in situ. The first wall substantially surrounds an enclosed reaction region confined within the reaction chamber of the reactor. To regenerate a worn first wall without opening the reactor chamber, a gaseous substance is introduced into the chamber, at least a portion of the gaseous substance comprising material, such as low Z refractory material, suitable for forming the first wall. At least a portion of this material is deposited, as by pyrolysis, in solid form on the first wall to regenerate the first wall, and residual gas is removed from the chamber. The chamber is then recharged with a mixture of deuterium and tritium. All the while the inflow of contaminants into the chamber is substantially excluded. Preferably, the pyrolysis of the gaseous substance is effected by energizing the coils used in the operation of the reactor for producing a plasma of deuterium and tritium ions in the reaction chamber.