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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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Carbonaceous chondrites isomeric alkanes identification by mass spectrometry and gas chromatography
Iron meteorites graphite-troilite nodules isomeric alkane composition, using gas chromatography and mass spectrometry
Mass spectrometry, Mossbauer spectrometry, and radioactivity measuring instruments
Aerospace science and technology transfer to air pollution control problems including mass spectrometry modifications and air pollution monitoring equipment improvements
Knudsen flow mass spectrometry, thermodynamics, and chemical bonding of titanium, zirconium, hafnium, and thorium carbides during high temperature vaporization
Apollo lunar orbital missions, discussing remote sensing and photographic equipment for lunar sounding and mass spectrometry, gegenschein experiments and high quality metric photography
Hydrocarbons pyrolysis in Knudsen cells at low pressures, using mass spectrometry to study reactions and products
Sterols isolation and identification from Pleistocene sediment by gas-liquid chromatography and combined gas chromatography-mass spectrometry
Vaporization thermodynamics of lanthanum carbides from Knudsen effusion mass spectrometry
High temperature vaporization of titanium, zirconium, hafnium and thorium carbides by Knudsen effusion mass spectrometry, measuring ion intensities, formation enthalpies and dissociation energies
Polynuclear aromatic hydrocarbons in Murchison meteorite, determining distribution by gas chromatography and mass spectrometry
Carbon compounds in Apollo 12 lunar fines and core samples, using pyrolysis, mass spectrometry, ion exchange chromatography and optical and electron microscopy
Murchison meteorite heterocyclic compounds contents, using gas chromatography-mass spectrometry
Crystal growth of III-V compound semiconductors from vapor phase, studying deposition processes chemistry by mass spectrometry
Apollo 12 lunar soil, breccia and igneous rock samples, determining elemental abundances with spark source mass spectrometry and neutron activation analysis
Chemical characteristics of carbon compounds in Apollo 11 and 12 lunar fines, using organic solvent extraction, mass spectrometry and gas chromatographic method
Tektite organic constituents evidence from high temperature mass spectrometry, investigating relation to formation process and terrestrial contamination
Mass spectrometric and target collection experiments were made at 1600 K to elucidate the mode of oxidative vaporization of two columbium alloys, fused-slurry-coated with a complex silicide former (Si-20Cr-Fe). At oxygen pressures up to 0.0005 torr the major vapor component detected by mass spectrometry for oxidized samples was gaseous silicon monoxide. Analysis of condensates collected at oxygen pressures of 0.1, 1.0 and 10 torr revealed that chromium-, silicon-, iron- and tungsten- containing species were the major products of vaporization. Equilibrium thermochemical diagrams were constructed for the metal-oxygen system corresponding to each constituent metal in both the coating and base alloy. The major vaporizing species are expected to be the gaseous oxides of chromium, silicon, iron and tungsten. Plots of vapor phase composition and maximum vaporization rate versus oxygen pressure were calculated for each coating constituent. The major contribution to weight loss by vaporization at oxygen pressures above 1 torr was shown to be the chromium-containing species.