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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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Detection and study of microbial population in upper atmosphere - simulated high altitude sampling with electrostatic precipitator
Growth response of Bacillus cereus and subtilis cells subjected to modified Martian environment with freeze cycles of different durations
Microbial contamination obtained on stainless steel, aluminum, glass, and lucite surfaces after twenty days exposure to room air
Ecology and thermal inactivation of microbes in and on interplanetary space vehicle components - microbiological procedures for disintegrating solids to small particles
Survival of microoranisms exposed to shock wave and cryogenic temperatures during upper atmospheric air sampling
Comparative levels and types of microbial contamination defected in industrial clean rooms
Microbial loads of spacecraft components measured prior to heat sterilization to determine if maximum tolerance is exceeded
Measurement techniques for determining microbial contamination from occupied space suits
Microbiological data of diet and closed ecological atmosphere effects on human intestinal and skin flora
Symposium on marine biology - growth rate, cycles, transportation, photosynthesis, distribution, sampling, nutrition, and light control of natural phytoplankton ecological systems
Water temperature, pH difference, geographical location, and other factors influence on composition and distribution of natural ecological systems of phytoplankton species
Sampling, staining, and counting of plankton populations
Role of ocean currents and icebergs in transporting phytoplankton species to distant areas - synecology
Effect of nutrients on competition of plankton species trapped in sea water in large translucent plastic bags
Response of algae in ecological systems to various metallic ion and nutrient additions
Continuous culture laboratory apparatus for giving truer simulation of plankton activity in ocean
On-site surveys and evaluations of existing facilities suitable for spacecraft sterilization and microbial clean assembly methods
An analytical model is developed for the survival times of organisms in heat sterilization in which the probability of inactivation as a function of exposure time is log-normally distributed. Experimental data is examined relative to this model and it is concluded that the model is valid except during the initial period of heating when an additional interaction between the organisms and their surrounding medium appears to be present. At long heating times, the log-normal model appears more accurate for extrapolating to low survival probabilities than the usual logarithmic survivor curves and is generally more conservative.