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A zirconia electroysis cell is an all-solid state (mainly ceramic) device consisting of two electrodes separated by a dense zirconia electrolyte. The cell electrochemically reduces carbon dioxide to oxygen and carbon monoxide at elevated temperatures (800 to 1000°C). The zirconia electrolysis cell provides a simple, lightweight, low-volume system for Mars In-Situ Resource Utilization (ISRU) applications. This paper describes the fabrication process and discusses the electrochemical performance and other properties of zirconia electrolysis cells made by the tape calendering method. Electrolytes produced by this method are very thin (micrometer-thick); the thin electrolyte reduces ohmic losses in the cell, permitting efficient operation at temperatures of 800°C or below.

An evaporative heat sink has been designed and built by AlliedSignal for NASA's Johnson Space Center. The unit is a demonstrator of a primary heat exchanger for NASA's prototype Crew Return Vehicle (CRV), designated the X-38. The primary heat exchanger is responsible for rejecting the heat produced by both the flight crew and the avionics. Spacecraft evaporative heat sinks utilize space vacuum as a resource to control the vapor pressure of a liquid. For the X-38, water has been chosen as the heat transport fluid. A portion of this coolant flow is bled off for use as the evaporant. At sufficiently low pressures, the water can be made to boil at temperatures approaching its freezing point. Heat transferred to liquid water in this state will cause the liquid to evaporate, thus creating a heat sink for the spacecraft's coolant loop. The CRV mission requires the heat exchanger to be compact and low in mass.

A condensing heat exchanger and filter assembly (CHXFA) has been developed by SECAN / AlliedSignal under a contract from Daimler-Chrysler Aerospace, Dornier, as a part of a European Space Agency program. The CHXFA is part of the Environmental Control and Life Support System (ECLSS) of the Columbus Orbital Facility (COF), the European Laboratory Module of the International Space Station (ISS). The CHXFA contains a filter to remove particulates from the air stream, and a differential pressure sensor to monitor pressure drop across the filter. Parallel condensing heat exchanger cores reduce the air temperature and absolute humidity level. Efficient air-water separation is achieved by a combination of a hydrophilic coating on the heat exchanger air flow passages and a water removal section. A thermal control valve regulates the temperature of the outlet air. A sensor to detect liquid carryover in the air stream is located downstream of the CHXFA.