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Dry heat inactivation of bacterial spores and influence of spore moisture content on z values as related to spacecraft sanitation
Effects of spore moisture content on resistance to dry heat sterilization
Moisture effects on Bacillus subtilis var. niger spores
Thermal inactivation of microbes relating to spacecraft sterilization
Spaceborne photography using different combinations of film and filters for earth resources surveys
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Thermal inactivation curves of Bacillus subtilis spores for decontamination of interplanetary space vehicle components
Poor land use and hydrologic practices and physical and chemical pollution of Anacostia river valley
Experimental system to detect acceptable levels of contamination for terminal sterilization process with unmanned landers
Evaluation equipment for terminal sterilization process on unmanned landers and determination of thermal inactivation curve of B. subtilis var. niger spores
Moisture effects on thermal inactivation of microbial spores for spacecraft sterilization
Correlation was obtained for determining sorptive capacity of carbon for pure and mixed contaminants under dry and humid conditions at various temperatures. Vacuum desorption rates were investigated for single particles and for sorbent beds. For sorbent beds, rate-determining step is Knudsen diffusion through interparticle voids.
A set of conditions in which 90 C was a more lethal temperature than 125 C for the destruction of Bacillus subtilis var. niger was identified as a function of relative humidity, with maximum effectiveness at 100% R.H. A systematic study of the influence of head-space moisture and temperature on the destruction of B. subtilis var. niger is reported.
Data showing that 90 C was a more effective temperature than 125 C for the destruction of Bacillus subtilis var. niger when the head-space moisture was fixed at 474 micrograms H2O/ml have been confirmed and are summarized. The influence of head-space moisture at 90 C was investigated and it was observed that as the head-space moisture was increased 474 micrograms H2O/ml, there was a corresponding increase in lethality of the system. This moisture level corresponded to 100% relative humidity at 90 C, and additional water in the cans should have had no effect. A profound descrease was observed in the destruction of the organisms when additional water was added. The discontinuity observed in these data is troublesome and must be resolved as the first step in an orderly exploration of low temperature inactivation of B. subtilis var. niger.
This report contains no significant results.
A concept for determining the constituent densities of ozone, atomic oxygen, aerosols, and neutral density in the 20 to 1000 km region of the atmosphere from a satellite was developed. The concept includes the daytime measurement of solar scattering at the earth's limb in selected narrow spectral bands of the ultraviolet and visible regions, and the measurement of selected (dayglow) emissions. Nighttime measurements of the atmospheric extinction of stellar energy in selected bands are also considered as are simultaneous measurements of the 5577 airglow and molecular oxygen emission in the Herzberg band. Radiative-transfer models and recursive inversion algorithms are developed for the measurements, and the accuracy of the concept is assessed.
There are no author-identified significant results in this report.
There are no author-identified significant results in this report.