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An automated Data Acquisition System (DAS) for managing and controlling an aerobic biodegradation process of solid biomass has been developed. The system employs a personal computer equipped with a data acquisition card and a visual basic software (LabVIEW). The DAS was integrated with the physical / chemical hardware (a bioreactor with its auxiliary equipment) through the necessary sensing devices. These sensing devices include in-line electrical-conductivity (EC), pH, and temperature probes. A flow sensor was inserted in the circulating sampling line to ensure that the in-line manifold does not contain air bubbles or clogged with fine particles. A gas analyzer was used to sample off-gases from the bioreactor to measure and record the change in the CO2 and O2 levels. The data acquisition system is capable of controlling the pH level inside the bioreactor by activating acid or base metering pumps.

A Tuskegee University research team has developed paper from inedible sweetpotato (Ipomoea batatas), peanut (Arachis hypogea), and soybean (Glycine max) plant residues for NASA's Advanced Life Support Program (ALS) for sustaining human life in space. The objective was to develop papers that could be used as a media for inocula and characterize their physical and mechanical properties. The tensile fracture behavior, micromorphological analysis, and fracture surface examination of peanut shells, sweetpotato stems, soybean pods, and a combination of sweetpotato stems (60%) / peanut shells (40%) papers were also investigated. The ultimate strength was 2.6 MPa, 9.2 MPa, 7.1 MPa and 6.5 MPa, respectively. All samples performed well as a media inocula.

Several plant growth systems have been tested for crop production in microgravity and lunar/Mars environments in support of NASA's Advanced Life Support Program and long-term human space missions. These systems have incorporated such design features as the nutrient film technique (NFT), microporous plates, microporous tubes, and expandable boundary chambers and have been developed and used to support sweetpotato production at Tuskegee University. In the present research, the performance of different sweetpotato cultivars in a microporous tube system with lunar simulant medium was studied. The lunar simulant is an inert aggregate with an average particle size of about 3 mm. Buried in this solid medium is a microporous tube. Nutrient solution is circulated through the microporous tube under a slight negative pressure. This pressure is controlled to allow a slight seepage from the tube with some accumulation of water in the solid medium, but no free water.