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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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At least 883 records · Page 49
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NASA NTRS1971

The measurement of radiation exposure of astronauts by radiochemical techniques

The concentrations of 23 major, minor, and trace elements in the fecal samples from the Apollo 12 and 13 astronauts are reported. Most elemental excretion rates are comparable to rates reported for earlier missions. Exceptions are noted for calcium, iron, and tin. Body calcium and iron losses appear to be reduced during the Apollo 12 and 13 missions such that losses now seem to be insignificant. Refined measurements of tin excretion rates agree with normal dietary intakes. Earlier reported tin values are in error. A new passive dosimetry canister was designed which contains foils of tantalum, copper, titanium, iron, cobalt, aluminum, and scandium. By measuring the concentrations of the various products of nuclear reactions in these metals after space exposure, the characteristics of the incident cosmic particles can be determined.

Brodzinski, R. L.↗
NASA NTRS1971

Ion microprobe mass analysis of lunar samples. Lunar sample program

Mass analyses of selected minerals, glasses and soil particles of lunar, meteoritic and terrestrial rocks have been made with the ion microprobe mass analyzer. Major, minor and trace element concentrations have been determined in situ in major and accessory mineral phases in polished rock thin sections. The Pb isotope ratios have been measured in U and Th bearing accessory minerals to yield radiometric age dates and heavy volatile elements have been sought on the surfaces of free particles from Apollo soil samples.

Anderson, C. A.↗
NASA NTRS1971

The measurement of radiation exposure of astronauts by radiochemical techniques

The urine specimens collected pre- and postflight from the Apollo 15 mission were analyzed for their radionuclide content. Cosmic radiation dose estimates of 695 and 660 mR are calculated from the observed Na-22 and Na-24 concentrations respectively. The concentrations of Na-22, Na-24, K-40, K-42, Cr-51, Fe-59, and Cs-137 are given. The potassium excretion patterns of high postflight and low preflight levels established for previous missions appears to be reversed for this mission. The concentrations of 23 major, minor, and trace elements in the fecal samples from the Apollo 14 astronauts are reported. Most elemental excretion rates are comparable to rates reported for earlier missions. The major exception is potassium where loss rates are the lowest ever observed. This coincides with the anomalously low excretion of potassium in postflight urine specimens. Apparent mass balance of calcium and iron continues as in the Apollo 12 and 13 missions.

Brodzinski, R. L.↗
NASA NTRS1971

Geochemical aspects of some Japanese lavas.

K, Rb, Sr, Ba and rare-earth concentrations in some Japanese lavas have been determined by mass-spectrometric stable-isotope dilution. The samples fall into three rare-earth groups corresponding to tholeiitic, high alumina and alkali basalts. Japanese tholeiites have trace element characteristics similar to those of oceanic ridge tholeiites except for distinctly higher relative concentrations of Ba. Japanese lavas may result from various degrees of partial fusion of amphibole eclogite.

Philpotts, J. A.↗
NASA NTRS1971

Volcanic petrology and geologic history of Northeast Bank, Southern California Borderland.

Basaltic rocks, hyaloclastites, and fossil fragments incorporated in volcanic material, dredged from the flanks of Northeast Bank on the Southern California Borderland, show trace element abundances typical of eastern Pacific basin alkali basalts but enriched (880 ppm) Ba. The fossil fragments, incorporated in breccia, hyaloclastite, and agglomerate, include a fauna which lived in less than 50 m of water, as well as forms from the intertidal zone. Bathymetry of the bank and the depth range of the dredged zone indicate that there has been at least 300 or as much as 500 m subsidence since the volcanism which incorporated the fauna in volcanic material. Isostatic adjustments due to crustal load of the bank can account for this subsidence.

Hawkins, J. W.↗
NASA NTRS1972

Rubidium-strontium and potassium-argon age of lunar sample 15555.

The lunar mare basalt 15555 from the edge of Hadley Rille has been dated at 3.3 b.y. by both rubidium-strontium and potassium-argon techniques. Age and trace element abundances closely resemble those of the Apollo 12 mare basalts. Data from lunar basalts obtained thus far indicate that they cannot be derived by simple fractionation from a homogeneous source.

Murthy, V. R.↗
NASA NTRS1971

Chemical composition of lunar anorthosites and their parent liquids.

Data obtained in a trace element analysis of some anorthosite and anorthositic fragments are presented. The low Mg concentrations of the Apollo 15 anorthosite and the KREEP anorthosite reflect the mineralogical purity of these samples. They are so pure that their composition can be taken as that of liquidus plagioclases. Some of the characteristics of the parent liquids of these plagioclases can be calculated from the liquid-plagioclase distribution coefficients.

Hubbard, N. J.↗
NASA NTRS1972

Compositional data for twenty-one Fra Mauro lunar materials.

Major, minor, and trace element analyses are presented for two igneous rocks, six breccias, four microbreccias, two breccia clasts, and six soils, as well as a sample of sawdust from rock 14066. Evaluation of the data suggests that the samples from the Fra Mauro highlands have the same nonterrestrial characteristics shown previously by the samples returned from the mare regions by Apollo 11 and 12 - namely, a high refractory element content, a lower volatile element content, and an excess reducing capacity above that due to FeO. The Fra Mauro soils have higher concentrations of Al2O3, Na2O, and K2O and lower amounts of FeO and TiO2 than do the mare soils. They also show a bimodal distribution of Ni, B, and Nb. The highland breccias are richer in SiO2, Al2O3, MgO, Na2O, and K2O than those returned from the mare lowlands. FeO, TiO2, and MnO are lower in concentration at Fra Mauro, and the highland breccias are more complex mineralogically than those collected previously.

Rose, H. J., Jr.↗