69,231 research outputs found
High-temperature thermionic emission microscope
Thermionic emission microscope was designed to operate with metal specimen cathode temperatures of 2000 degrees C
Kink-antikink interactions in the double sine-Gordon equation and the problem of resonance frequencies
We studied the kink-antikink collision process for the "double sine-Gordon"
(DSG) equation in 1+1 dimensions at different values of the potential parameter
. For small values of we discuss the problem of resonance frequencies.
We give qualitative explanation of the frequency shift in comparison with the
frequency of the discrete level in the potential well of isolated kink. We show
that in this region of the parameter the effective long-range interaction
between kink and antikink takes place.Comment: 9 pages, LaTeX, 4 figures (eps
Thermionic research and development program Final report
Rhenium electrode material investigation and performance studies of low temperature cesium vapor thermionic converter
Ecology and thermal inactivation of microbes in and on interplanetary space vehicle components
The experiments conducted to determine the heat resistance of Bacillus megaterium ATCC 6458 at 90 and 100 C were completed. Estimates from replicate experiments at eight percent relative humidities (less than 0.001 to 100% RH) for each temperature were computed. A Bacillus cereus strain with high heat resistance was cultured and the resistance determined in phosphate buffer (D sub 121.1 = 2.16 min and z = 8.7 C). The profile of the dry heat resistance of B. megaterium is summarized and the most resistant condition to the three spores (Bacillus subtilis var. niger, ATCC 29669, and Bacillus stearothermophilus, strain 1518) is compared
Thermionic research and development program Final report, 15 Jul. 1966 - 15 Jan. 1968
Thermionic research and development program - improvement of performance of low emitter temperature cesium vapor thermionic converter
Ecology and thermal inactivation of microbes in and on interplanetary space vehicle components
Dry heat treatment is specified as the preferred means for the terminal sterilization of spacecraft and for decontamination of spacecraft components. The presence of organisms highly resistant to dry heat in soil and fallout around assembly and industrial manufacturing areas is shown. The dry heat survival characteristics of the Cape Kennedy isolate 4-6 B. brevis spores is demonstrated. The presence of hardy organisms from soil samples obtained from geographical areas of the United States is shown. A resistant fraction appears to occur in low numbers in a soil sample. The heat resistance characteristics of 4-6 B. brevis and B. subtilis var. niger spores are compared. Their morphological characteristics are compared by scanning electron microscopy
Ecology and thermal inactivation of microbes in and on interplanetary space vehicle components
Statistical techniques which have relevance to studies on the thermal inactivation on bacterial spores are discussed
Ecology and thermal inactivation of microbes in and on interplanetary space vehicle components
The heat resistance of Bacillus subtilis var. niger was measured from 85 to 125 C using moisture levels of % RH or = 0.001 to 100. Curves are presented which characterize thermal destruction using thermal death times defined as F values at a given combination of three moisture and temperature conditions. The times required at 100 C for reductions of 99.99% of the initial population were estimated for the three moisture conditions. The linear model (from which estimates of D are obtained) was satisfactory for estimating thermal death times (% RH or = 0.07) in the plate count range. Estimates based on observed thermal death times and D values for % RH = 100 diverged so that D values generally gave a more conservative estimate over the temperature range 90 to 125 C. Estimates of Z sub F and Z sub L ranged from 32.1 to 58.3 C for % RH of or = 0.07 and 100. A Z sub D = 30.0 was obtained for data observed at % RH or = 0.07
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