Abstract: The present invention is concerned with a method for the production of fine and ultrafine powders of various materials such as metals, alloys, ceramics, composites etc., through a transferred arc plasma system. The method comprises vaporizing or decomposing the material in the plasma reactor, condensing the vapor in a quench tube comprising two sections, the first one for indirectly cooling or heating the vapor, and the second one for directly cooling the vapor. The powder is recovered in a conventional collection unit. The two step condensation in the quench tube allows a substantial control of powder properties like crystallinity, size distribution and mean particle size.

Abstract: An electrode structure for electrolytic cells is disclosed. The electrode structure comprises a central current-collector structure having high points on at least one side and adapted to be placed vertically in the electrolytic cell, and a porous electrode secured to the high points of the current-collector structure on at least one side thereof so as to form an essentially-planar pre-electrode surface. The high points of the current-collector are arranged so as to allow an unimpeded rise of the evolved gases to the top of the electrode.

Abstract: A voltage stabilized solid polyolefin dielectric composition is disclosed. The dielectric composition comprises a polyolefin containing a voltage stabilizing amount of an additive selected from the class of dyes identified in the Color Index as being of the solvent type possessing either an azo or a quinoid type structure, or having a xanthene structure exhibiting fluorescence. The solvent dyes must be soluble in or melt miscible with the polyolefin. The solvent dyes must also be stable at the processing temperature and under the conditions of use.