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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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Ferromagnetic Ni band structure and magnetic breakdown between opposite spin bands, noting de Hass-van Alphen effect, exchange splitting and spin-orbit interaction
Local time asymmetries in increase of electron fluxes in outer Van Allen zone during substorms
Time profiles of trapped Van Allen electrons in auroral zones
Widths measurements of van der Waals broadened Si I spectral lines by shock tube and scanning Fabry-Perot interferometer, using argon as perturbing gas
Shock and vibration characteristics of panel van with spring suspension system
Measurements of Van der Waals Na 5889 A in He with piston compressor light source
Method for simulating Van Allen belt proton energy spectra
Lorentz absorption line shape computations in radiation scattered by homogeneous planetary atmosphere compared with results for isotropic scattering by van de Hulst similarity relations
Plasma turbulence in Van Allen belts, examining weak turbulent electromagnetic wave properties, with emphasis on trapped energetic particles radiation
Van Allen radiation belts energetic electrons injection and distribution due to magnetic storms, using satellite-borne spectrometers
Acceleration and precipitation of Van Allen outer zone energetic electrons, using correlation experiment between magnetosphere and auroral zone
Van Allen electrons acceleration and precipitation during magnetospheric substorms in relation to auroral processes, discussing energy and pitch angle diffusion processes
Fokker-Planck equation used to describe process of electron loss from Van Allen zones due to pitch angle scattering by electromagnetic disturbances
Van Allen belt radiation on Tiros/TOS/ITOS spacecrafts - graphs
Nonadiabatic effects in van der Waal line broadening, taking into account mixing between degenerate magnetic sublevels in atomic collisions
Estimates were made of the number of trapped protons and electrons encountered by vehicles on low-thrust trajectories through the Van Allen belts. The estimates serve as a first step in assessing whether these radiations present a problem to on-board sensitive components and payload. The integrated proton spectra and electron spectra are presented for the case of a trajectory described by a vehicle with a constant-thrust acceleration A sub c equal to 0.001 meter/sq sec. This value of acceleration corresponds to a trip time of about 54 days from low earth orbit to synchronous orbit. It is shown that the time spent in the belts and hence the radiation encountered vary nearly inversely with the value of thrust acceleration. Thus, the integrated spectral values presented for the case of A sub c = 0.001 meter/sq sec can be generalized for any other value of thrust acceleration by multiplying them by the factor 0.001/A sub c.
Variational functionals of Braunn and Rebane (1972) for the imagery-frequency polarizability (IFP) have been generalized by the method of Gramian inequalities to give rigorous upper and lower bounds, valid even when the true (but unknown) unperturbed wavefunction must be represented by a variational approximation. Using these formulas in conjunction with flexible variational trial functions, tight error bounds are computed for the IFP and the associated two- and three-body van der Waals interaction constants of the ground 1(1S) and metastable 2(1,3S) states of He and Li(+). These bounds generally establish the ground-state properties to within a fraction of a per cent and metastable properties to within a few per cent, permitting a comparative assessment of competing theoretical methods at this level of accuracy. Unlike previous 'error bounds' for these properties, the present results have a completely a priori theoretical character, with no empirical input data.
Vehicle maximum speed, range at constant speed, range over stop-and-go driving schedules, maximum acceleration, gradeability, gradeability limit, road energy consumption, road power, indicated energy consumption, braking capability, battery charger efficiency, and battery characteristics were determined for a modified utility van powered by sixteen 6-volt batteries connected in series. A chopper controller actuated by a foot accelerator pedal changes the voltage applied to the 22-kilowatt (30-hp) series-wound drive motor. In addition to the conventional hydraulic braking system, the vehicle has hydraulic regenerative braking. Cycle tests and acceleration tests were conducted with and without hydraulic regeneration.