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An approach to the isolation and concentration of volatile organic compounds from a water sample prior to chemical analysis in a microgravity environment has been previously described (Reference 1). The Volatile Organics Concentrator (VOC) system was designed for attachment to a gas chromatograph/mass spectrometer (GC/MS) for analysis of the volatile organics in water on Space Station Freedom. The VOC concept utilizes a primary solid sorbent for collection and concentration of the the organics from water, with subsequent transfer using nitrogen gas through a permeation dryer tube to a secondary solid sorbent tube. The secondary solid sorbent is thermally desorbed to a gas chromatograph for separation of the volatiles which are detected using a mass spectrometer.

An approach to the isolation and concentration of volatile organic compounds from a water sample prior to chemical analysis in a microgravity environment has been previously described (Reference 1). The Volatile Organics Concentrator (VOC) system was designed to attach to a gas chromatograph/mass spectrometer (GC/MS) for analysis of volatile organic compounds in water on Space Station Freedom. The VOC utilizes a primary solid sorbent for collection and concentration of the volatile compounds, transfer of the volatiles through a permeation dryer to a secondary solid sorbent, followed by thermal desorption of volatiles from the secondary sorbent onto a GC/MS system. Fabrications and preliminary testing of the VOC breadboard using a gas chromatography equipped with flame ionization detector has been previously described (Reference 2). These results have indicated that the VOC will meet or exceed the goals set for the program.

Controlled Ecological Life Support System (CELSS) technology is critical to the Space Exploration Initiative. NASA's Kennedy Space Center (KSC) has been performing CELSS research tor several years, developing data related to CELSS design. We have developed OCAM (Object-oriented CELSS Analysis and Modeling), a CELSS modeling tool, and have used this tool to evaluate CELSS concepts, using this data. In using OCAM, a CELSS is broken down into components, and each component is modeled as a combination of containers, converters and gates which store, process and exchange carbon, hydrogen, and oxygen on a daily basis. Multiple crops and plant types can be simulated. Resource recovery options modeled include combustion, leaching, enzyme treatment, aerobic or anaerobic digestion, and mushroom and fish growth. Simulation results include printouts and time-history graphs of total system mass, biomass, carbon dioxide, and oxygen quantities; energy consumption; and manpower requirements.

Solar proton events (SPEs) are preceded by the optical, radio, and X-ray emissions of solar flares. Thus the capability for providing early warning of SPEs is possible if the particle fluxes can be correlated with the electromagnetic signatures from the sun. We have developed and refined the correlations of the peak proton flux at geosynchronous orbit with the solar X-ray emissions using data collected by the GOES spacecraft and supplied by NOAA. We have used data from over most of solar cycle 21 and the early portion of cycle 22 to extend the data base and improve the correlations. A power law relationship has been assumed between the peak proton flux and the X-ray fluence in both the 0.5-4 and 1-8 Angstrom bands of the GOES X-ray sensors. The correlation coefficients are approximately the same for both X-ray energy bands. We have also examined and obtained the correlation between the X-ray energy and peak proton flux at different proton energies.

The process used to identify, select and design an approach to the isolation and concentration of volatile organic compounds from a water sample prior to chemical analysis in a microgravity environment is described. The Volatile Organics Concentrator (VOC) system described in this paper has been designed for attachment to a gas chromatograph/mass spectrometer (GC/MS) for analysis of volatile organics in water on Space Station. In this work, in order to rank the many identified approaches, the system was broken into three critical areas. These were gases, volatile separation from water and water removal/GC/MS interface. Five options involving different gases (or combinations) for potential use in the VOC and GC/MS system were identified and ranked. Nine options for separation of volatiles from the water phase were identified and ranked. Seven options for use in the water removal/GC column and MS interface were also identified and included in overall considerations.