Abstract: A dual-valve reverse poppet thermostat for use in a vehicle cooling system. The thermostat includes a cup having a temperature sensitive element that actuates a piston causing the piston to move axially upwards. Movement of the piston initiates the gradual opening of a preliminary valve to initiate coolant flow and equalize pressure to open a main valve. The preliminary valve and main valve are biased towards a closed position by biasing spring members.

Abstract: A regenerable cryosorption pump with a movable physical barrier in which the barrier includes a cylindrical body closed at one end and having a circumferential baffle around the open end. The baffle engages a flange on the hydrogen isotope condensing and pumping surface to require all gases entering the pump during normal operation to pass through the hydrogen isotope condensing and pumping surface, thus avoiding bypass of that surface. The barrier is advanced by a bellows system to isolate the hydrogen isotope condensing and pumping surface from the sorbent surface during regeneration and thus ensuring separation of hydrogen isotopes such as tritium from helium which is sorbed onto the sorbent surface.