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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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Growth cycles in fossil pelecypod shells and relationship to tidal cycles in earth-moon system
Relationship of geologic time and days per lunar month to growth patterns in fossil and recent molluscan shells
Paleozoic plant fossil carbohydrate components by chromatographic and enzymatic methods compared with modern plants
Mars surface coloration attributed to limonite as fossil weathering product of hydrosphere during early period in planetary evolution
Carbohydrate content range of various fossils and associated sedimentary matrix, using phenol-sulfuric acid method
Carbohydrate analyses of upper carboniferous plant fossils in England, noting monosaccharides separation
Amino acid components in paleozoic plant fossils and rock samples noting glycine, serine and glutamic acid
Early Precambrian Onverwacht microstructures studied in petrographic thin sections and powdered preparations for possibility of oldest terrestrial fossils
Phenolic aldehydes generated from lignin in fossil woods and carbonaceous sediments by oxidative degradation
Observing growth rhythms in shells of fossil marine invertebrates and relationship to tidal cycles in earth-moon system
Gum Nebula-fossil Stromgren sphere of Vela X supernova, deriving ionization model from interstellar measurements
Fossil lunar magnetism observations, using magnetometer data from orbiter Explorer 35
Gas rich Kapoeta howardite composition, evolution, high particle fossil track densities and normal track rich crystals spatial relations
The application of remotely-sensed information to the mineral, fossil fuel, and geothermal energy extraction industry is investigated. Public and private cost savings are documented in geologic mapping activities. Benefits and capabilities accruing to the ERS system are assessed. It is shown that remote sensing aids in resource extraction, as well as the monitoring of several dynamic phenomena, including disturbed lands, reclamation, erosion, glaciation, and volcanic and seismic activity.
The observed frequency with which infrared excesses appear in F, G, and K supergiants of luminosity class Ia supports the idea that these excesses arise in a 'fossil' circumstellar dust shell that was formed during a prior M-super-giant phase of evolution. The required leftward evolution of the star on the H-R diagram would then imply that the Ledoux, rather than the Schwarzschild, criterion for convective mixing is the correct criterion to use in stellar evolution calculations.
The amino acid composition and the extent of racemization in several modern and fossil woods are reported. The method of analysis is described, and data are presented on the total amino acid concentration, the amino acid ratios, and the enantiomeric ratios in each sample. It is found that the amino acid concentration per gram of dry wood decreases with age of the sample, that the extent of racemization increases with increasing age, and that the amounts of aspartic acid, threonine, and serine decrease relative to valine with increasing age. The relative racemization rates of amino acids in wood, bone, and aqueous solution are compared, and it is shown that racemization in wood is much slower than in bone or aqueous solution. Racemization results for woods from the Kalambo Falls area of Zambia are used to calculate a minimum age of 110,000 years for the transition between the Sangoan and Acheulian industries at that site. This result is shown to be consistent with numerous radiometric dates for older Acheulian sites in Africa and to compare well with geologically inferred dates for the beginning of the Eemian and the end of the Acheulian industry in southern Africa.
The isotopic composition of Mg was measured in different phases of a Ca-Al-rich inclusion in the Allende meteorite. Large excesses of Mg-26 of up to 10% were found. These excesses correlate strictly with the Al-27/Mg-24 ratio for four coexisting phases with distinctive chemical compositions. Models of in situ decay of Al-26 within the solar system and of mixing of interstellar dust grains containing fossil Al-26 with normal solar system material are presented. The observed correlation provides definitive evidence for the presence of Al-26 in the early solar system. This requires either injection of freshly synthesized nucleosynthetic material into the solar system immediately before condensation and planet formation, or local production within the solar system by intense activity of the early sun. Planets promptly produced from material with the inferred Al-26/Al-27 would melt within about 300,000 years.
The paper discusses the application of remotely sensed data from orbital satellites to the exploration for fossil and nuclear fuels. Geological applications of Landsat data are described including map editing, lithologic identification, structural geology, and mineral exploration. Specific results in fuel exploration are reviewed and a series of related Landsat images is included.