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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 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
NASA NTRS1977

Genesis of howardites, diogenites, and eucrites

The reported investigation was mainly concerned with the precise determinations of major-, minor-, and trace-element abundances, especially the REE abundances in the bulk howardites in order to establish the bulk rock composition for the future chemical-mineralogical, petrographic studies of different rock types on the chemically unique howardites and diogenites if they exist. From the chemical data for the major-element abundances and the REE patterns of the howardites analyzed, it is evident that these howardites are predominantly composed of eucritic and diogenitic components. The analytical results for howardites and diogenites are shown in two tables together with the results for CRB-1. The chondritic normalized K, Sr, Ba, REE, Hf, and Sc abundances of these howardites are plotted in two graphs.

Fukuoka, T.↗
NASA NTRS1975

On the origin of high-Ti mare basalts

Analyses were conducted of sixteen Apollo 17 mare basalts for alkali, alkaline-earth, and rare-earth elements, Co, and Sc. The obtained data were utilized in a study concerning the nature of the igneous processes responsible for the chemical variations among the high-Ti, low-K basalts. Estimates were obtained regarding the abundances of the large-ion, lithophile elements in the source regions for the basalts. It is shown that the source regions could plausibly have been produced by processes believed to have occurred during the early history of the moon. Attention is given to chemical variations among the Apollo 17 mare basalts, near-surface (low-pressure) crystal fractionation, partial melting, limits on the extent of partial melting, and a summary of possible events leading to formation of high-Ti mare basalts.

Shih, C.-Y.↗
NASA NTRS1979

Design of high efficiency HLE solar cells for space and terrestrial applications

A first-order analysis of HLE cells is presented for both beginning-of-life and end-of-life conditions. Based on this analysis and on experimentally observed values for material parameters. Design approaches for both space and terrestrial cells are presented. The approaches result in specification of doping levels, junction depths, and surface conditions. The proposed structures are projected to have both high V sub OC and high J sub SC.

Neugroschel, A.↗
NASA NTRS1978

Lines in the 2736-3303 A spectrum of Arcturus

Results are reported for a study of the near-UV spectrum of Arcturus as recorded with a balloon-borne echelle spectrograph-vidicon detector system in the spectral region from 2700 to 3300 A at 0.1-A resolution. A condensed version of the Arcturus spectrum is provided along with profile descriptions and identifications for 383 absorption features detected in the near-UV. Elements definitely present include Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Zr, and La. Elements with spectral features indicating possible presence include Be, O, S, K, Ga, Ge, Nb, Sn, Gd, and Bi. Line blocking is shown to be extensive in the spectral region studied, and eight possible continuum 'windows' are found in the near-UV. Emission lines of chromospheric origin due to Mg II, Fe I, Fe II, and possibly Cr II are also identified in the region from 2736 to 3303 A. It is noted that the Fe I emission lines at 2823 and 2844 A are optically pumped.

Stencel, R. E.↗
NASA NTRS1978

Trace element composition of Luna 24 Crisium VLT basalt

The origins of the individual particles analyzed from the Luna 24 core and the information they provide on the trace-element composition of Mare Crisium basalt are considered. Previous analyses of several Luna 24 soil fragments are reviewed. It is concluded that: (1) the average trace-element concentrations for 12 VLT basalt fragments are the best available estimates for bulk samples of Crisium VLT basalt; (2) there is weak evidence that the average Crisium basalt might have a small positive Eu anomaly relative to chondritic matter; (3) the soils contain components from sources other than the Crisium VLT basalt; and (4) there is no convincing information in concentrations of rare-earth elements, Co, Sc, FeO, or Na2O among the analyzed fragments to indicate more than one parent basalt.

Haskin, L. A.↗
NASA NTRS1978

The relative abundances of the elements silicon through nickel in the low energy galactic cosmic rays

Measurements of the relative abundances of the elements Si through Ni in galactic cosmic rays in the energy interval 72 to 450 MeV/nucleon are reported based on data collected by a cosmic-ray telescope on the IMP 8 satellite. The measured abundances are compared with propagation calculations using various distributions of path lengths. It is found that the measurements favor an exponential distribution of path lengths truncated at short path lengths. The source abundances of Si, Ca, Fe, and Ni derived by extrapolating the measured abundances back to the source are shown to be comparable to the solar-system abundances. The relevance of the measurements of Sc through Mn to the Mn-54 radioactive decay is examined.

Garcia-Munoz, M.↗
NASA NTRS1978

Experimental partitioning of rare earth elements and scandium among armalcolite, ilmenite, olivine and mare basalt liquid

An experimental study was carried out to measure partition coefficients for two rare-earth elements (Sm and Tm) and Sc among armalcolite, ilmenite, olivine and liquid coexisting in a system modeled on high-Ti mare basalt 74275. This 'primitive' sample was chosen for study because its major and trace element chemistry as well as its equilibrium phase relations at atmospheric pressure are known from previous studies. Beta-track analytical techniques were used so that partition coefficients could be measured in an environment whose bulk trace element composition is similar to that of the natural basalt. Partition coefficients for Cr and Mn were determined in the same experiments by microprobe analysis. The only equilibrium partial melting model appears to be one in which ilmenite is initially present in the source region but is consumed by melting before segregation of the high-Ti mare basalt liquid from the residue.

Irving, A. J.↗
NASA NTRS1979

Trace elements in the Allende meteorite. IV - Amoeboid olivine aggregates

INAA data for Ca, Sc, Hf, La, Ce, Sm, Eu, Tb, Yb, Lu, Os, Ir, Ru, Na, Cl, Br, Fe, Mn, Cr, Co, Au, As, and Sb are presented for ten amoeboid aggregates from the Allende meteorite. Only one lacks olivine. Seven of the remainder, as a group, have cosmic proportions of refractory lithophile and siderophile elements and appear to have formed when coarse-grained Allende inclusion material underwent partial reaction with a low-temperature nebular gas and mixture with FeO-rich olivine. The other two have highly fractionated abundances of refractory elements relative to one another compared to Cl chondrites, including Group II REE patterns, and probably formed by the mixing of fine-grained Allende inclusion material with FeO-rich olivine. Non-refractory siderophile components are also different in composition in each type of amoeboid olivine aggregate.

Grossman, L.↗
NASA NTRS1979

X-ray locations and sizes of clusters of galaxies observed with the HEAO 1 scanning modulation collimator

Observations with the HEAO 1 scanning modulation collimator (MC) have yielded improved locations for the centroids of X-ray sources in clusters of galaxies dominated by a giant central galaxy. For A85, A478, A1795, A2029, A2199, A2319 A, and SC 0316-444, these positions are consistent with those of the clusters' dominant cD galaxies. By comparing the HEAO 1 MC flux with that obtained with the HEAO 1 A-2 experiment, estimates of the X-ray sizes for these clusters have been obtained. The correlation of these sizes with other cluster properties is discussed.

Schwarz, J.↗
NASA NTRS1979

Solar heating and hot water system installed at Municipal Building complex, Abbeville, South Carolina

Information on the solar energy system installed at the new municipal building for the City of Abbeville, SC is presented, including a description of solar energy system and buildings, lessons learned, and recommendations. The solar space heating system is a direct air heating system. The flat roof collector panel was sized to provide 75% of the heating requirement based on an average day in January. The collectors used are job-built with two layers of filon corrugated fiberglass FRP panels cross lapped make up the cover. The storage consists of a pit filled with washed 3/4 in - 1 1/2 in diameter crushed granite stone. The air handler includes the air handling mechanism, motorized dampers, air circulating blower, sensors, control relays and mode control unit. Solar heating of water is provided only those times when the hot air in the collector is exhausted to the outside.

Source record↗
NASA NTRS1979

Galileo quartz clock

A quartz oscillator for use in the Galileo experiment (orbiter and Probe) for Jupiter mission 1982 are described. This oscillator has achieved significant performance breakthroughs by the use of an SC cut, double rotated, crystal in a titanium dewar flask. Some of the performance parameters as well as the design feature of the oscillator are presented.

Block, M.↗
NASA NTRS1979

Initial results on 5 MHz quartz oscillators equipped with BVA resonators

The techniques of fabricating BVA resonators are discussed in terms of aging, amplitude-frequency effect, and acceleration sensitivity. Results on 5 MHz resonators concerning aging versus drive level, reduced amplitude-frequency effect, frequency and phase stability performance, and frequency retrace following power interruption are presented. It is indicated that a zero aging rate is possible at a drive level which depends on the qaurtz material used. For natural AT quartz, a level of 70 to 90 micro W appears to be optimum, and for SC quartz approximately 160 micro W.

Besson, R. J.↗
NASA NTRS1979

Petrographic and chemical characterization of igneous lithic clasts from mesosiderites and howardites and comparison with eucrites and diogenites

Petrographic, electron microprobe, and instrumental neutron activation analysis (INAA) studies of igneous lithic clasts separated from mesosiderites and howardites and INAA investigation of whole rock eucrites and diogenites are presented. The trace element abundances in basaltic lithic clasts indicate more complex differentiation episodes than in eucrites which include sequential melting and expulsion of liquid from the source region and remelting of cumulate materials. Pyroxenites from mesosiderites show slight enrichments in Sc and Mn than diogenites suggesting that these pyroxenites are not fragments of diogenites. It is concluded that the heat source characteristics are spatially and temporally variable, suggesting that heating of the differentiated meteorite parent bodies may have partly come from outside the parent body.

Mittlefehldt, D. W.↗
NASA NTRS1979

The chemical components of highlands breccias

Component models for polymict highlands breccias are considered, where rocks are assumed to be mixtures of end-members unaffected by such processes as fumarolic volatiles and impact-induced volatilization. Evidence points to pristine norites as substantial contributors to highlands breccias; the bulk major element compositions of breccias average noritic anorthosite, and norites are the second-most abundant of pristine samples. In addition, plots of element abundances in breccias indicate that KREEP in highlands breccias is not of Apollo 14 composition but is higher in Ti and Sc, and probably lower in incompatibles.

Ryder, G.↗
NASA NTRS1979

A measurement of the cosmic-ray source abundance of Ca-40

The measured charge composition of the galactic cosmic rays from Ar to Ni and the isotopic composition of the elements Ca and Sc are presented. It is found that the ratio Ca-40/Fe at the cosmic-ray source is (5.9 plus or minus 1.9)%. This result is in good agreement with the meteoritic value (6.8 plus or minus 1.0)%.

Tarle, G.↗
NASA NTRS1980

Design, fabrication, test, qualification and price analysis for third generation design solar cell modules

An updated program plan is presented showing the task descriptions depicting the work, progress, achievements, and the cause of any deviations from the original plan (SC-1), and how this impacted on the original schedule of the program. In addition there is an update documenting all design alterations made during the pre-production phase and a complete up to date set of engineering and manufacturing documentation (CM-1). The purpose of the work in the original plan was to explore, design, develop, test, and deliver 1000 watts of prototype flat plate, photovoltaic modules appropriate for use in applications in the 20 to 500 kilowatt range and which show potential for meeting the 1986 cost goals.

Source record↗
NASA NTRS1980

Hg and Pt-metals in meteorite carbon-rich residues - Suggestions for possible host phase for Hg

Carbon-rich and oxide residual phases have been isolated from Allende and Murchison by acid demineralization for the determination of their Hg, Pt-metal, Cr, Sc, Co, and Fe contents. Experimental procedures used eliminated the possibility of exogenous and endogenous contaminant trace elements from coprecipitating with the residues. Large enrichments of Hg and Pt-metals were found in Allende but not in Murchison residues. Hg-release profiles from stepwise heating experiments suggest a sulfide as the host for Hg. Diffusion calculations for Hg based on these experiments indicate an activation energy of 7-8 kcal/mol, the same as that for Hg in troilite from an iron meteorite. This is further support for a sulfide host phase for Hg. Equilibration of Hg with this phase at approximately 900 K is indicated. Reasons for the presence of Pt-metals in noncosmic relative abundances are explored.

Jovanovic, S.↗
NASA NTRS1980

The energy dependence of the ratios of secondary to primary elements in the cosmic radiation

The secondary to primary ratios B/C, N/O and (Sc-Mn)/Fe in the galactic cosmic rays have been measured in the overall energy interval 30-180 MeV/n with the University of Chicago cosmic ray telescope on board the satellite IMP-8 during the period 1974-1978. These results, together with the values of the same ratios measured at higher energies, have been compared to the results of cosmic ray propagation calculations using different pathlength distributions (PLD) and different levels of solar modulation, in order to select a single set of parameters consistent with all the measured ratios.

Garcia-Munoz, M.↗