Abstract: An apparatus and method for the cryogenic purification of gaseous mixtures is provided. The apparatus comprises a heat-insulated hermetically sealed vessel which contains liquid hydrogen. Immersed within the liquid hydrogen are a number of serially connected cartridges which contain chips of a thermally conductive mixture. A mixture of neon and helium is input into the apparatus. The neon freezes, while the helium passes through the apparatus in a gaseous state. The resulting neon is allowed to thaw into a liquid or gaseous form and is highly pure.

Abstract: An underreamer which may be mounted on a core drill to allow single phase underreaming or creation of a bore hole of larger diameter beneath a pilot hole. A plurality of levers are powered by a plurality of corresponding jacks which are adapted to exert pressure on the levers in order to cause them to extend beyond the periphery of the expander body. Each lever contains at least one roller-cutter rotatably mounted to the lever so that when the levers are forced outward, the roller-cutters crush rock beyond the periphery of the expander body and thus underream the bore hole.