Abstract: A process is provided for extracting high purity oxygen from a gas generator turbine exhaust stream by passing the turbine exhaust over the feed side of solid electrolyte membrane selective to the permeation of oxygen over other components of the exhaust stream to separate the oxygen from the exhaust stream, and removing the oxygen product stream from the permeate side of the membrane. The reject exhaust stream is then passed through a power generating turbine to recover net power.

Abstract: A process is provided for extracting high purity oxygen from gas turbine exhaust streams by passing the gas turbine exhaust over the feed side of solid electrolyte membrane selective to the permeation of oxygen over other components of the exhaust stream to separate the oxygen from the exhaust stream, and removing the oxygen product stream from the permeate side of the membrane.

Abstract: A counter flow heat exchanger comprising a plurality of tubes disposed in a bundle array or tube within tube configuration to enhance heat transfer between high and low pressure tubes in the array or tube in tube configuration. Also disclosed are a method of increasing the heat transfer capacity of a tube bundle heat exchanger and a liquid helium temperature refrigerator or a reliquefier utilizing the heat exchanger.

Abstract: A heat exchanger for a fast cooldown cryostat having high pressure and low pressure flow paths wherein a low pressure flow path is defined by a finely divided matrix which in turn defines a plurality of flow paths and said high pressure flow path is disposed in heat exchange relationshp to said matrix.

Abstract: A counter flow heat exchanger comprising a plurality of tubes disposed in a bundle array or tube within tube configuration to enhance heat transfer between high and low pressure tubes in the array or tube in tube configuration. Also disclosed are a method of increasing the heat transfer capacity of a tube bundle heat exchanger and a liquid helium temperature refrigerator or a reliquefier utilizing the heat exchanger.

Abstract: A counter flow heat exchanger comprising a plurality of tubes disposed in a bundle array or tube within tube configuration to enhance heat transfer between high and low pressure tubes in the array or tube in tube configuration. Also disclosed are a method of increasing the heat transfer capacity of a tube bundle heat exchanger and a liquid helium temperature refrigerator or a reliquefier utilizing the heat exchanger.

Abstract: Fibrous material disposed in the Joule-Thomson orifice and/or the high pressure tube of a Joule-Thomson heat exchanger provides an effective flow restrictor in the orifice and means to prevent blockage because of contaminants in the fluid freezing and clogging the orifice. A Joule-Thomson device of this type can be fabricated for use as a cryostat to be disposed in confined space.

Abstract: A counter flow heat exchanger comprising a central low pressure return tube deformed intermediate its ends to enhance heat transfer capability wrapped by a high pressure tube to conduct fluid to an expansion device. Also disclosed are a method of increasing the heat transfer capacity of a tube bundle heat exchanger and a liquid helium temperature refrigerator or a reliquefier utilizing the heat exchanger.

Abstract: Hydrogen is stored at cryogenic temperatures by adsorption on porous carbon having a nitrogen BET apparent surface area above about 1500 m.sup.2 /g. Hydrogen can be adsorbed and desorbed in the context of a cryopump, having as the pumping element a panel, having large particles of pressed porous carbon thereon.

Abstract: A counter flow heat exchanger comprising a central low pressure return tube deformed intermediate its ends to enhance heat transfer capability wrapped by a high pressure tube to conduct fluid to an expansion device. Also disclosed are a method of increasing the heat transfer capacity of a tube bundle heat exchanger and a liquid helium temperature refrigerator or a reliquefier utilizing the heat exchanger.

Abstract: A miniature apparatus for compressing gases is disclosed in which an elastomer disposed between two opposing electrostrictive or piezoelectric ceramic blocks, or between a single electrostrictive or piezoelectric ceramic block and a rigid surface, is caused to extrude into or recede from a channel defined adjacent to the elastomer in response to application or removal of an electric field from the blocks. Individual cells of blocks and elastomer are connected to effect a gas compression by peristaltic activation of the individual cells. The apparatus is self-valving in that the first and last cells operate as inlet and outlet valves, respectively. Preferred electrostrictive and piezoelectric ceramic materials are disclosed, and an alternative, non-peristaltic embodiment of the apparatus is described.

Abstract: A superconducting quantum interference device (SQUID) magnetic detection apparatus detects magnetic fields, signals, and anomalies at remote locations. Two remotely rotatable SQUID gradiometers may be housed in a cryogenic environment to search for and locate unambiguously magnetic anomalies. The SQUID magnetic detection apparatus can be used to determine the azimuth of a hydrofracture by first flooding the hydrofracture with a ferrofluid to create an artificial magnetic anomaly therein.

Abstract: A composite formed from large pieces of aggregate formed from (1) metal hydride (or hydride-former) powder and (2) either metal powder or plastic powder or both is prepared. The composite has large macroscopic interconnected pores (much larger than the sizes of the powders which are used) and will have a very fast heat transfer rate and low windage loss. It will be useful, for example, in heat engines, hydrogen storage devices, and refrigerator components which depend for their utility upon both a fast rate of hydriding and dehydriding. Additionally, a method of preparing the composite and a method of increasing the rates of hydriding and dehydriding of metal hydrides are also given.

Abstract: The disclosure is directed to an apparatus and method for maintaining a body at cryogenic temperatures at a remote location such as down a borehole for an extended period of time. A housing contains a body comprising a material having a high specific heat at cryogenic temperatures such as between about 2 and 15 K. The body contains an orifice for containing an instrument or instruments operable at superconducting temperatures. The apparatus is precooled at the surface and lowered into a borehole to a desired depth, such as 2 to 3 miles. The instruments are operated, and the apparatus withdrawn, the material of the body maintaining the very low temperatures at which the instrument(s) operate for a sufficient period of time at the remote or downhole location. The material may comprise a rare earth compound, such as Gd.sub.2 O.sub.3, Gd.sub.2 Se.sub.3, Gd.sub.2 O.sub.2 S or GdAlO.sub.3. Monoclinic and C-phase gadolinium oxides work well. A low temperature is maintainable at a remote location for several hours.

Abstract: The disclosure is directed to an active magnetic regenerator apparatus and method. Brayton, Stirling, Ericsson, and Carnot cycles and the like may be utilized in an active magnetic regenerator to provide efficient refrigeration over relatively large temperature ranges.

Abstract: A composite superconductor formed from a high specific heat ceramic such as gadolinium oxide or gadolinium-aluminum oxide and a conventional metal conductor such as copper or aluminum which are insolubly mixed together to provide adiabatic stability in a superconducting mode of operation. The addition of a few percent of insoluble gadolinium-aluminum oxide powder or gadolinium oxide powder to copper, increases the measured specific heat of the composite by one to two orders of magnitude below the 5.degree. K. level while maintaining the high thermal and electrical conductivity of the conventional metal conductor.

Abstract: A high temperature magnetic refrigerator which uses a Stirling-like cycle in which rotating magnetic working material is heated in zero field and adiabatically magnetized, cooled in high field, then adiabatically demagnetized. During this cycle said working material is in heat exchange with a pumped fluid which absorbs heat from a low temperature heat source and deposits heat in a high temperature reservoir. The magnetic refrigeration cycle operates at an efficiency 70% of Carnot.

Abstract: A continuous, noncyclic magnetic refrigerator consisting of a liquid nitrogen cryostat having a motor-driven wheel with a pressed, porous rare earth compound as a rim that rotates through two thermally separated inner reservoirs of liquid helium, the first reservoir being at an elevated temperature relative to the second reservoir, two superconducting magnets of different field strengths, the larger of which is situate in the first reservoir and is adjacent to the said rim while the smaller magnet is positioned in the second reservoir adjacent to said rim, and said reservoir or reservoirs having a convection-driver pump to increase circulation of the helium in said second or first and second reservoirs through said porous rim.