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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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Critical pinning current density for initiating flux flow in Pb-Bi type II superconducting foils, noting dependence on surface to volume ratio
Cell performance and thermal regeneration of a thermally regenerative cell uses lithium and tin and a fused-salt electrolyte. The emf of the Li-Sn cell, as a function of cathode-alloy composition, is shown to resemble that of the Na-Bi cell.
By using Bi-gram and Tri-gram tables, a pattern can be formed to determine failure modes and mechanisms. Computer programs provide accurate predictions of cell failure several thousand cycles before actual failure.
Improving electron optical performance and thermal stability of sterilizable bi-alkali image dissector tubes
Low resistance Bi thin film complex electrical impedance in IR range, stating methods and equivalent circuits for determining impedance
Gas laser application to magnetospectroscopy of graphite, Bi, As and pyrolytic graphite single crystals
Laser induced vaporization of Bi compounds with group VIa elements, analyzing vapor species, condensed phase and molecular configurations by mass spectroscopy
Oscillatory transverse and longitudinal magnetostriction in single crystal Bi, obtaining deformation potentials
Bi polycrystalline film grown by vacuum deposition on amorphous substrates investigated for electron microscope beam effects
Ternary phase diagrams and quaternary excess free energy prediction using binary data, applied to Pb-Sn-Zn, Ag-Pd-Cu and Pb-Sn-Cd-Bi systems
Electric propulsion plasma thrust beam and ambient space plasma electrostatic equilibration, considering various charged particle parameters involved in bi-plasma system interactions
Strong magnetic fields effect on field emission currents in Bi, Zn, Ta and W
Development and flight test of bi-mode radar for three dimensional velocity readout and slant range measurement to ground over wide range of velocities and altitudes
Squaring loops for establishing coherent carrier reference for bi-phase PSK modulation, deriving optimal presquaring filter
In-Bi whisker growth by squeeze technique, measuring crystal structure by X ray analysis and melting point method
Neutron activation analysis of Apollo 11 lunar fines, determining Pb 204, U, Bi and Tl contents
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.
A 5000 watt xenon-mercury high pressure lamp was used to produce a continuous ultraviolet spectrum. Human and animal exposures were made to establish the photokeratitis threshold and abiotic action spectrum. The lower limit of the abiotic action spectrum was 220 nm while the upper limit was 310 nm. The radiant exposure threshold at 270 nm was 0.005 watts/sq cm for the rabbit, 0.004 watts/sq cm for the primate, and 0.004 watts/ sq cm for the human. The rabbit curve was bi-peaked with minimums at 220 nm, 240 nm and 270 nm. The primate curve was tri-peaked with minimums at 220 nm, 240 nm and 270 nm. The human data showed a rather shallow curve with a minimum at 270 nm. Formulas and calculations are given to predict minimum exposure times for ocular damage to man in outer space, to establish valid safety criteria, and to establish protective design criteria.