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An important milestone in the ongoing effort by NASA to develop and refine closed-loop water recycling systems for human space flight was reached during the summer of 1996 with the successful completion of Phase II of the Lunar Mars Life Support Testing Program at Johnson Space Center. Part of Phase II involved testing a water-recycling system in a closed test chamber continuously occupied by four human subjects for thirty days. The Phase II crew began the test with a supply of water that had been processed and certified for human use. As the test progressed, humidity condensate, urine, and wastewater from personal hygiene and housekeeping activities were reclaimed and reused several times. Samples were collected from various points in the reclamation process during the thirty day test. The data verified the water-processing hardware can reliably remove wastewater contaminants and produce reclaimed water that meets NASA standards for hygiene- and potable-quality water.

To satisfy a requirement to supply water to Mir station, a process for treating iodinated water on the Shuttle was developed and implemented. The treatment system consists of packed columns for removing iodine and a syringe-based injection system for adding ionic silver, the biocide used in Mir water. Technical and potable grade water is produced and transferred in batches using collapsible 44-liter contingency water containers (CWCs). Silver is added to the water via injection of a solution from preloaded syringes. Minerals are also added to water destined for drinking. During the previous four Shuttle-Mir docking missions a total of 2781 liters (735 gallons) of water produced by the Shuttle fuel cells was processed using this method and transferred to Mir. To verify the quality of the processed water, samples were collected during flight and returned for chemical analysis.

During Lunar missions, NASA's new Orion Crew Exploration Vehicle (CEV) may benefit from mass savings and increased reliability by the use of a passive, capillary-driven Static Phase Separator (SPS) for urine collection, containment, and disposal in place of a rotary-fan separator and wastewater storage tank. The design of a capillary separator addresses unique challenges for microgravity fluid management for liquids with a wide range of possible contact angles and high air-to-liquid flow ratio. This paper presents the iterative process leading to a successful test in a reduced gravity aircraft of the SPS concept. Using appropriately scaled test conditions, the resulting prototype allows for a range of wetting properties with complete separation of liquid from gas.

In preparation for future planetary exploration, NASA-Johnson Space Center has developed a critical path plan for food and nutrition research needs. The plan highlights the risk factors pertaining to food and nutrition associated with exposure to the space flight environment as well as the possible consequences if no corrective measures are implemented. Included in the plan are the initiating events such as microgravity, remote environment and mission duration, which obviously impact the risk factors. The plan includes points of intervention where mitigating factors can be implemented to avoid outcomes such as malnutrition and unsafe foods. Physiological changes induced by lack of gravity, as well as increased exposure to radiation, may alter nutrient bio-availability and/or nutrient requirements. An inadequate food system, whether due to technical limitations or nutritional shortcomings, can result in serious consequences.

Yardney Technical Products is developing a high energy density Li-ion cell tailored for NASA's Extravehicular Mobility Unit battery. The goal of the program is to develop a Li-ion technology which offers long storage and cycle life in a system which provides energy density and exercise performance comparable to the current 6.7kg Zn-AgO battery. The Zinc-Silver Oxide cells which are most commonly used in this application provide 400 Wh/l with a 32 cycle life at 26.6Ah and 1.55V with a rated wet life of 425 days. To improve the energy density of the Li-ion cells we have focused on improving the energy density of its components. In addition to using thin metal foil current collectors, the energy density of the cathode material was improved by utilizing a high capacity Co doped nickel oxide material. Further efforts have focused on developing a more energy dense carbonaceous anode material. The results of this effort are reviewed.