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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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Hemispherical emittance of structural materials & coatings under simulated spacecraft conditions over wide temperature range
Mechanism of spatial perception and synergetic activity of cerebral hemispheres
Importance of synergetic activity in cerebral hemispheres to spatial perception
Exploratory tests were made to determine the reduction of heat transfer resulting from ejection of gases at the stagnation point on a hemisphere-cone at a nominal Mach number of about 9 and at stagnation enthalpies up to 1600 BTU per pound. Helium, nitrogen, and argon gases were used as coolants. The ratio of mass flow of coolant to the mass flow of air swept out by the model projected area was less than 0.20 in all cases. The experimental heat-transfer data were normalized by the calculated stagnation-point values based on test conditions in the tunnel and are presented as a function of the surface distance from the stagnation point. The variation of shock standoff distances with mass flow and volumetric flow of the gaseous ejectants is presented along with photographs of the luminous flow field of the model during tests.
Surface roughness effect on hemispherical and specular reflectance of metallic surfaces irradiated by black body irradiation
Black body irradiation of metal surfaces to determine roughness effects on hemispherical and and specular reflectance for various temperatures and angles of incidence
Hemispherical spectral emittance of ablation chars, carbon, and zirconia during atmospheric reentry
Time variation of total hemispherical emission of polished platinum surfaces at high temperatures
Hemispherical spectral emission of ablation chars, carbon, and zirconium oxide formed during reentry
Hemispherical total emittance and normal solar absorptance of selected materials at temperature range 280 to 600 degrees K - thermal radiation parameters
Solar reflectance as function of incidence angle and total hemispherical emittance of space suit materials
Local flow conditions over hemispherically blunted 25 deg cone for shallow reentry trajectory
Integrating sphere reflectometer for measuring absolute hemispherical spectral reflectance of surfaces
Complementary slot-dipole antenna with hemispherical coverage for use in passive interferometer beacon acquisition system
Meteorological wind, and temperature data from atmospheric radiosonde soundings in Southern Hemisphere
Nike Apache pitot tube rocket sounding measuring of Southern Hemisphere stratosphere and mesosphere along west coast of South America
Radar meteor surveys from opposite hemispheres, showing meteor showers containing small number of meteoroids association with known comets
Axisymmetric dynamic response of hemispherical shells under arbitrary loading formulated using elastic bending theory