Abstract: Process for activating a getter composed of a porous barium pellet comprising maintaining a barium pellet in an inert atmosphere, placing the pellet in an enclosed chamber, evacuating the chamber and heating the evacuated chamber containing the pellet to about 800.degree.F for about two hours to activate same by removing gases from the surfaces of the pellet and an activated barium getter comprising a perforated metal or alloy can preferably composed of tantalum containing a barium pellet which has been heated in a vacuum to about 800.degree.F for about two hours.

Abstract: Thermopile mounting comprising elongated thermoelectric elements with insulation therebetween arrayed into a thermopile block, electrical interconnections for said elements, a hot plate and a cold plate at each end of the thermopile and a plurality of tensioned wires extending from the hot plate to the cold plate in a manner to transfer the stress of the wires to the thermopile to place same under compression, said wires having a strength to thermal conductivity ratio of greater than 250,000.

Abstract: Novel header for use in nuclear applications comprised of a base containing at least one bore, a niobium terminal passing through said bore sealed in an alumina plug which, in turn, is sealed in a bore defined in the base.