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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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Chemical vapor deposition process for production of high purity chromium metal containing thorium oxide dispersion material
Iron-base and nickel-base alloys exhibit good oxidation resistance and improved ductility with addition of small amounts of yttrium, tantalum /or hafnium/, and thorium. They can be used in applications above the operating temperatures of the superalloys, if high strength materials are not required.
Sintered aluminum oxide and yttrium-thorium oxide ceramics for astronomical mirror materials
Thorium phosphide anti-type microstructure of La-Rh system by X ray diffraction, discussing bcc structure, lattice constants, etc
Dispersion strengthened Ni-Cr alloys creep properties, investigating temperature, applied stress and thorium dioxide particles effects
Low temperature anharmonicity in thorium dioxide with Co 57 impurities, using Mossbauer effect of Fe 57
Least squares analyses of uranium and thorium alpha spectra
Abundance of uranium, thorium, and plutonium isotopes in Apollo 12 soil and breccia samples
Mass spectroscopy of lunar samples to determine uranium, thorium, and lead content
Knudsen flow mass spectrometry, thermodynamics, and chemical bonding of titanium, zirconium, hafnium, and thorium carbides during high temperature vaporization
Rare earth and thorium alloying of chromium and mechanism for controlling nitrogen embrittlement
Thorium wavelength measurements by interferometry, noting weighted averages as secondary standards of length
High temperature vaporization of titanium, zirconium, hafnium and thorium carbides by Knudsen effusion mass spectrometry, measuring ion intensities, formation enthalpies and dissociation energies
A new type of interferometer for use in Fourier spectroscopy has been devised at the Aime Cotton Laboratory of the National Center for Scientific Research (CNRS), Orsay, France. With this interferometer and newly developed computational techniques, interferograms comprising as many as one million samples can now be transformed. The techniques are described, and examples of spectra of thorium and holmium, derived from one million-point interferograms, are presented.
Mapping the radon emanation of the moon was studied to find potential areas of high activity by detection of radon isotopes and their daughter products. It was felt that based on observation of regions overflown by Apollo spacecraft and within the field of view of the alpha-particle spectrometer, a radon map could be constructed, identifying and locating lunar areas of outgassing. The basic theory of radon migration from natural concentrations of uranium and thorium is discussed in terms of radon decay and the production of alpha particles. The preliminary analysis of the results indicates no significant alpha emission.
Two basalts, two breccias, and two soils from Apollo 15 were analyzed by nondestructive gamma-ray spectrometry. The concentrations of potassium, thorium, and uranium in the basalts were similar to those in the Apollo 12 basalts, but the potassium:uranium ratios were somewhat higher. Primordial radioelements were enriched in the soils and breccia, consistent with a two-component mixture of mare basalt and up to 20 percent foreign component (KREEP). The abundance patterns for cosmogenic radionuclides implied surface sampling for all specimens. The galactic cosmic-ray production rate of vanadium-48 was determined as 57 (plus or minus 11) disintegrations per minute per kilogram of iron. Cobalt-56 concentrations were used to estimate the intensity of the solar flare of January 25, 1971.
Analyses have been made of lead, uranium, and thorium in two soil samples from the Luna 16 mission. Lead was found to be distinctly radiogenic, but significantly less radiogenic than other lunar soils. The Th/U ratio was found to be 3.8, and the uranium concentration was the lowest so far found for lunar soils.