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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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Amplitude independent attenuation of longitudinal ultrasound propagating in /001/ direction in single crystal superconducting Pb compared with BCS predictions
Si-Ge/cold/-Pb-Te/hot/ segmented thermocouples joined by bonding to tungsten intermediate, determining efficiency by measuring heat flux from cold side
Test data printout tables for cycling performance of Ag Cd, Ag Zn, Ni Cd, Pb Ca, and lead-acid cells
Superconducting flux-flow resistivity minimum in Pb-Tl alloy, discussing thermal dissipation associated with temperature gradients across moving fluxoid
Tunnel junctions with low background currents made by reacting active gas layer adsorbed on Nb film surface with Pb upper film to form barrier
Pb isotopic analysis using double spike mass spectrometric method to achieve reproducibility and accuracy, discussing principles and performance
High temperature ion source developed for implantation and surface reactions of Ar, Pb, and Ga ions
Plastic deformation effects on superconductivity of wire specimens of high purity Pb, In and Tl cold worked at liquid He and annealed
Iron troilite meteorites lead isotopic, Pb and U concentrations, considering fractionation and terrestrial contamination effects
Apollo 11 lunar rocks, breccia and fines U, Th and Pb isotopes systematics, considering implications for lunar history
Josephson junction formation, and chemisorption of organics on Pb surfaces
Chemisorption energies of organics on Pb surface by extended Hueckel molecular orbital technique
Apollo 11 lunar soil and rock samples under low level beta spectrometry, measuring radon daughter Pb 210
Cascaded thermoelectric generator using Si-Ge and Pb-Te elements with heat pipe interstage coupling
An effort was made to determine the effects of electromagnetic radiation on the terminal properties of electrochemical cells. Various constituents of the battery were measured to determine basic electromagnetic properties. These properties were used to predict how much radiation would be absorbed by a battery in a particular field configuration. The frequency range covered from 0 to 40 GHz with the greatest emphasis on the microwave range from 2.6 to 40 GHz. The measurements were made on NiCd, AgZn, and Pb acid cells. Results from observation show nothing which suggested any interaction between radiation and cells, and no incidence of any peaks of energy absorption was observed.
Gamma analyses of the neutron-activated fecal samples from the Apollo 12 and 13 missions were completed, and the data are being evaluated. Samples of the exposed Apollo 12 solar wind composition foil and blank foils were obtained for analysis of the Po-2/0 (Pb-210, Rn-222) content. It is expected that the determination of the Po-210 content of these foils will yield the concentration of radon atoms incident on the foil while exposed to the lunar atmosphere, and this indirectly will permit an estimate of the average uranium concentration of the lunar surface. Proposals to measure the cosmic-ray intensity and energy spectra inside and outside of late Apollo and Project Skylab spacecraft by exposing and subsequently analyzing pure metal foils, and to measure the elemental mass balance in Project Skylab astronauts by instrumental neutron activation analysis of the intake and excreta are summarized.
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.
The Maki contribution to the conductivity above the superconducting transition temperature is regularized within the framework of the BCS theory. This is achieved through the renormalization of the impurity scattering vertex by inclusion of the effects of pair fluctuations. The conductivity is evaluated for a thin film. It depends only on the reduced temperature and the normal resistance per square. Fair agreement is found with Al films over a wide temperature range. Agreement is not found with experiments on Bi, Pb and Ga films, which apparently contain a strong additional pair-breaking effect. The temperature range in which interactions among fluctuations become important in the Maki conductivity is generally larger than that given by the Ginzburg criterion.