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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 739 records · Page 41
All sourcesNASA NTRSDOE OSTI
NASA NTRS1970

Large-angle p-d scattering at 580 Mev

Proton-deuteron elastic large angle scattering cross sections, noting backward peak consistent with baryon exchange mechanism with resonance transfer

Boschitz, E. T.↗
NASA NTRS1975

Technology assessment of portable energy RDT and P

Results are presented of a workshop conducted to assess portable energy technology. The results were evaluated and areas for future research were considered. Several research categories were studied: increasing presently available fuel supplies, developing new fuel sources, utilization of new transportation fuels, improving conservation practices, and equitable distribution of fuel supplies. Several research projects were proposed, and work statements were constructed for those considered suitable.

Vanston, J. H., Jr.↗
NASA NTRS1987

P-31 Magnetic Resonance Spectroscopy (MRS) of limb muscles during bedrest with exercise countermeasures

Nineteen volunteers in bed with head down tilt (-6 deg) for 1 month and doing or not exercise training while in bed (lido or ergometer) had their limb muscle studied by magnetic resonance spectroscopy. A protocol of repetitive exercise in the magnet was set and a wooden probe designed to support the limb and to allow exercise. Spectra were recorded continuously during the protocol. In each spectrum, inorganic phosphate, phosphocreatin, adenosin triphosphate, and pH were measured. All the subjects were studied before, after bedrest, and 6 weeks later. After 1 month, the lido group show no changes in the spectra of their leg muscles while the group doing no exercise or ergometer do. For the arms, a loss of muscle function is only seen in the group doing no exercise.

Berry, P.↗
NASA NTRS1990

Coplanar waveguide discontinuities for P-I-N diode switches and filter applications

A full wave space domain integral equation (SDIE) analysis of coplanar waveguide (CPW) two port discontinuities is presented. An experimental setup to measure the S-parameters of such discontinuities is described. Experimental and theoretical results for CPW realizations of pass-band and stop-band filters are presented. The S-parameters of such structures are plotted in the frequency range 5 to 25 GHz.

Dib, N. I.↗
NASA NTRS1989

The high-overtone p-mode spectrum of the rapidly oscillating Ap star HR 1217 (HD 24712) - Results of a frequency analysis of 324 hr of multi-site photometric observations obtained during a 46-d time-span in 1986

The present high-speed photometry for the rapidly oscillating Ap star HR 1217 indicates that the 6-min light variations are amplitude-modulated, in phase with the magnetic variations. Amplitude and magnetic maxima coincide, while the mean light minimum occurs at a perhaps significantly different time. It is established that HR 1217 is an oblique rotator with a centered dipole magnetic field, as well as an oblique pulsator whose pulsation and magnetic axes are aligned. There are six principal frequencies of pulsation; the secondary frequencies indicate that the principal ones are amplitude-modulated on a time-scale of months.

Kurtz, D. W.↗
NASA NTRS1951

Preliminary investigation of the control of a gas-turbine engine for a helicopter / Richard P. Krebs

An analog investigation of the power plant for a gas-turbine powered helicopter indicates that currently proposed turbine-propeller engine controls are satisfactory for helicopter application. Power increases from one-half to full rated at altitudes from sea level to 15,000 feet could be made in less than 4 seconds with either the rotor or propellers absorbing the engine power.

ENGINES, CONTROL - TURBINE-PROPELLER ENGINES↗
NASA NTRS1953

Analysis of the turbojet engine for propulsion of supersonic fighter airplanes / David S. Gabriel, Richard P. Krebs, E.Clinton Wilcox, Stanley L.Koutz

An analytical investigation was made of two supersonic interceptor type airplanes to determine the most desirable turbojet engine characteristics for this application The airplanes were designed differently primarily because of the amount of subsonic flight incorporated in the flight plan--one flight having none and the other, a cruise radius of 400 nautical miles. Several power plant design variables were varied independently to determine the effect of changes in each parameter on airplane performance. These parameters included compressor pressure ratio, compressor efficiency, turbine-inlet temperature, afterburner temperature, engine specific weight, and air-handling capacity. The effects of using a convergent-divergent exhaust nozzle and of changing the design flight Mach number were also investigated.

ENGINES, TURBOJET↗