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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Dry column chromatography principles applied in microscale produce technique to minimize time in preparing and analyzing colorless constituents of soluble mixtures. Glass pipette microcolumns filled with finely sieved adsorbents permit capillary attraction and separation in 3 to 15 minutes. Technique is adaptable to gas chromatography.
Relationship between dry heat inactivation of microorganisms and water content of spore
Empirically based kinetic model describing synergistic inactivation of dry Bacillus subtilis by combined heat and gamma radiation environment
Diffusion model of dry heat sterilization
Rational model for spacecraft dry heat sterilization
Dry and water-saturated sintered fiber metal wick thermal conductivity, obtaining semiempirical correlations for solid and fluid phases and void fraction
Growth of bacteria in soils from Antarctic dry valleys providing soil microbial ecology as Mars model
Sliding friction and wear tests of polyimide, pyrrone, and poly/amide-imide/ resin seals on steel rotating disks at 260 C in dry air for hydraulic actuator boundary lubrication
Influence of aluminum on friction and wear of iron-aluminum alloys dry and lubricated in argon atmosphere
Atmospheric-lithostatic pressure ratio effects on explosive crater dimensions in dry soil
Vacuum environment tests of microwave ovens and various freeze-dried foods cooked in oven to determine outgassing effects
Development of technique to clear blockages in hydraulic and pneumatic pipes is discussed. Technique consists of using dry ice plug to separate sensitive components from flushing fluid. Diagram of equipment and principles of operation are presented.
Electronic circuitry contains new operational amplifier which incorporates monolithic super-gain transistors. Electrode does not provide voltage amplification; instead, it acts as current amplifier to make it possible to pick up electrical potentials from surface of highly resistant dry skin.
Separation of plant pigments which can be accomplished on thin-layer silica plates with mixture of petroleum ether, halocarbon, acetone, and polar solvent can be readily translated into dry-column technique that yields reproducible chromatograms after elution in fashion of liquid chromatography with fluorimeter as detector. Best solvent system was found to be mixture of petroleum ether, dichloromethane, acetone, and ethyl acetate.
The author has identified the following significant results. Reconnaissance geologic mapping can be done with 60-70% accuracy in the Dry Valleys of Antarctica using ERTS-1 imagery. Bedrock geology can be mapped much better than unconsolidated deposits of Quaternary age. Mapping of bedrock geology is facilitated by lack of vegetation, whereas mapping of Quaternary deposits is hindered by lack of vegetation. Antarctic images show remarkable clarity and under certain conditions (moderate relief, selection of the optimum band for specific rock types, stereo-viewing) irregular contacts can be mapped in local areas that are amazing like those mapped at a scale of 1:25,000, but, of course, lack details due to resolution limitations. ERTS-1 images should be a valuable aid to Antarctic geologists who have some limited ground truth and wish to extend boundaries of geologic mapping from known areas.
Microorganisms capable of growth at 7 C were enumerated and isolated from soil samples from the manufacture area (Denver, Colorado) and assembly area (Cape Kennedy, Florida) of the Viking spacecraft. Temperature requirements were determined for these isolates, and those growing at 3 C, but not at 32 C were designated as obligate psychrophiles in this investigation. These were identified to major generic groups, and the population density of obligate psychrophiles from the various groups was determined. Dry heat D-values were found for those spores that demonstrated growth or survival under a simulated Martian environment.
An air drying process has been analyzed which is intended to reduce the water vapor content of a stratospheric sample to below one part per million by weight, based upon the removal of the water as it passes through a phosphorous pentoxide absorber. The analysis indicates that the method is feasible. Dependence on ram pressure to maintain flow through the absorber appears questionable and consideration should be given to other means.
A two degrees-of-freedom (TDF) rate integrating gyro in the strapdown mode is a candidate for attitude sensing in a spacecraft navigation system, since it provides an additional axis of information for a relatively small increase in hardware complexity. A type of gyro which has not been fully exploited is of the dry, tuned, TDF design, in which the spring constant of the suspension system is effectively cancelled by the dynamic antispring of a swiveling, rotating, gimbal. The use of this unconventional gyro in a digital rebalance loop was investigated.