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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.

The Near Infrared Camera and Multi Object Spectrometer (NICMOS) was installed in the Hubble Space Telescope in February 1997. Shortly thereafter, the instrument experienced a thermal short in its solid nitrogen dewar system which will shorten its useful life significantly. A reverse Brayton cycle mechanical refrigerator will be installed during the third servicing mission (SM3) to provide cooling for the instrument, and thereby extend its life. A Capillary Pump Loop (CPL) and radiator system has been designed, built and tested to remove up to 500 watts of heat from the mechanical cooler and its electronics. This paper will describe the CPL system in detail and present the results of the extensive testing and qualification program.

Determination of the so-called stress concentration factor (Kt) is essential for the correct design of components subject to fatigue-inducing loading. The paper introduces methods and software for stress concentration analysis and techniques for structural design optimization based on the redistribution of material to balance stress concentration efforts.

This paper presents the results of a design study of a low cost Jet Fuel Starter (JFS). The JFS is a small free turbine turboshaft engine with a peak output of 150 horsepower. The design concentrates on high output per unit volume and weight, and on low cost. A low speed, four stage axial compressor design results in a compact, lightweight starter. Die castings and a radial pin construction for both the static structure and the compressor rotor provide the most significant cost savings over conventional gas turbine fabrication methods. The low speed concentric shaft design (approximately 70 percent of usual design practice) permits a simple two bearing shaft suspension for both rotors. The resulting close coupling of the turbines reduces the number of expensive hot end components to only five parts.

Powder metallurgy cold forming processes provide several advantages: economy of material, minimal machining, close tolerances, high density and lower production costs. IN-861 is an air hardenable ferrous alloy of 2% Ni, 1% Mo, 0.7% Mn plus carbon produced from mixed elemental powders. Specimens were alloyed at three carbon levels and sintered at several temperatures in order to relate ductility and workability to alloy composition and preform sintering temperature. Results indicate that increasing carbon content and sintering temperature required increasing preform forming stresses. Also, ductility of the preform increased with increasing sintering temperature and decreasing carbon content. Further additions of manganese raise the forming stresses, however a marked reduction in ductility is noted. Additions of molybdenum appear to have little effect upon strength, but decrease the ductility.