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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 127 records · Page 7
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

Nocturnal bird migration in opaque clouds

The use of a tracking radar to measure the flight paths of migrating birds on nights with opaque clouds is discussed. The effects of wind and lack of visual references are examined. The limitations of the radar observations are described, and samples of tracks obtained during radar observations are included. It is concluded that nonvisual mechanisms of orientation make it possible for birds to migrate in opaque clouds, but the exact nature of the sensory information cannot be determined by radar observations.

Griffin, D. R.↗
NASA NTRS1972

Tolerance to external breathing resistance with particular reference to high inspiratory resistance

The ability of men to exercise while breathing through graded inspiratory resistances was studied in order to define acceptable respiratory mouthpiece assembly standards. Experimental results with subjects wearing breathing masks and walking for 30 min on treadmills were used to calculate expiratory work rates. It is concluded that the airflow must be appropriate to the upper limit of minute ventilation likely to be encountered in the men wearing the apparatus.

Bentley, R. A.↗
NASA NTRS1972

Influence of facemask design on operational performance

Spirometric measurements of oxygen volume and determination of the amount of argon in exhaled breath are used to analyze facemask design efficiency during treadmill walking tests with subjects carrying plastic hoods filled with argon. Facemask leakage measurements established the better performance of a pneumatic seal type mask in comparison with plain seal type masks.

Griffin, O. G.↗
NASA NTRS1973

Long-term material compatibility testing system

System includes procedure for hermetically sealing solid materials and fluids in glass ampoule and use of temperature-controlled facility containing sample holder, which permits sample containers to be retrieved safely and conveniently. Solid material and fluid are sealed within chemically-clean glass ampoule according to highly detailed procedure.

Toth, L. R.↗
NASA NTRS1972

Space processing: A projection

Estimates concerning space manufacturing, which might well become the largest and most specific application of space technology by the end of the century are given. Two classes of materials are considered - electronic crystals and biologicals.

Mccreight, L. R.↗
NASA NTRS1972

Apollo 15 mission report. Supplement 3: Ascent propulsion system final flight evaluation

The results are presented of the postflight analysis of the ascent propulsion system (APS) performance during the Apollo 15 Mission. The information presented includes: (1) calculated performance values for the APS lunar liftoff burn; (2) disucssion of analysis techniques, problems and assumptions; (3) comparison of postflight analysis and preflight prediction; (4) reaction control system (RCS) duty cycle included in the APS performance analysis; (5) transient performance analysis; and (6) the APS propellant consumption values.

Griffin, W. G.↗
NASA NTRS1972

Apollo 12 mission report. Supplement 4: Ascent propulsion system final flight evaluation

The results of the postflight analysis of the ascent propulsion system (APS) performance during the Apollo 12 Mission are presented. The steady-state performance analysis, and pressurization system are discussed along with the propellant loading and usage, APS overburn, and burn time. It is concluded that APS flight performance reconstructions for LM-3, LM-4, LM-5, and LM-6 indicate that engine performance prediction techniques are conservative.

Griffin, W. G.↗
NASA NTRS1973

Reactions of singlet oxygen with pine pollen.

A study was initiated to determine whether viable atmospheric particles such as plant pollens and fungal spores containing unsaturated lipids can interact with singlet oxygen to give oxygenated products that are potentially toxic. The results obtained confirm that surface and near surface components of common viable particulate matter in the atmosphere may be subject to rapid oxidation by singlet oxygen, leading to products which are probably allylic hydroperoxides. In connection with increasing atmospheric pollution, it is important to note that materials toxic to mammalian lung tissue may be oxidatively produced on the surfaces of viable particulate matter.

Dowty, B.↗
NASA NTRS1972

Apollo 15 mission report. Supplement 3: Ascent propulsion system final flight evaluation

Results from the postflight analysis of the ascent propulsion system (APS) performance during the Apollo 15 mission are presented. The duty cycle for the LM-10 APS consisted of two firings, and ascent stage liftoff from the lunar surface and the terminal phase ignition (TPI) burn. An evaluation was made of APS performance for the first firing and found to be satisfactory. No propulsion data was received from the second APS burn; however, all indications were that the burn was nominal. All performance parameters were well within their LM-10 3-sigma limits. Calculated throat erosion at engine cutoff for the LM-10 APS was approximately 3 percent greater than predicted.

Griffin, W. G.↗
NASA NTRS1974

Design of an automatic weight scale for an isolette

The design of an infant weight scale is reported that fits into an isolette without disturbing its controlled atmosphere. The scale platform uses strain gages to measure electronically deflections of cantilever beams positioned at its four corners. The weight of the infant is proportional to the sum of the output voltages produced by the gauges on each beam of the scale.

Peterka, R. J.↗
NASA NTRS1974

Apparatus for conducting flow electrophoresis in the substantial absence of gravity

A zero-g, constant flow electrophoretic separating apparatus is presented. The apparatus is composed a deflecting member to spread carrier fluid across a conduit, and an end wall with a valve located in the conduit past the separation electrodes from which layers of carrier and sample may be extracted. Electrode electrolyte is separated from the carrier and continually circulated and cleaned.

Griffin, R. N.↗
NASA NTRS1974

Apollo 16, LM-11 ascent propulsion system final flight evaluation

The duty cycle for the LM-11 APS consisted of two firings, an ascent stage liftoff from the lunar surface, and the terminal phase initiation (TPI) burn. APS performance for the first firing was evaluated and found to be satisfactory. No propulsion data were received from the second APS burn; however, all indications were that the burn was nominal. Engine ignition for the APS lunar liftoff burn occured at the Apollo elapsed time (AET) of 175:31:47.9 (hours:minutes:seconds). Burn duration was 427.7 seconds.

Griffin, W. G.↗
NASA NTRS1973

Metastable states of highly excited heavy ions

Description of the method used and results obtained in an experimental study of the metastable states of highly stripped heavy ions, aimed at determining the lifetimes of such states by the rates of autoionization and radiation. The significance and limitations of the results presented are discussed.

Pegg, D. J.↗
NASA NTRS1974

Extreme ultraviolet spectra of highly ionized oxygen and fluorine

The foil-excitation method has been used to study the extreme ultraviolet spectra of highly ionized oxygen and fluorine. Several previously unreported lines in heliumlike fluorine are reported and other newly reported lines in heliumlike oxygen have been measured to higher accuracy. Included in the measurements are certain heliumlike oxygen transitions of significance in interpretation of solar-flare spectral observations. The wavelength determinations are usually in good agreement with calculated results which includes relativistic corrections, but discrepancies arise when nonrelativistic calculations are used. A comparison of the present results and those recently obtained by theta-pinch and laser-induced plasma sources is made for both heliumlike and lithiumlike ions; a few discrepancies occur, with results in most cases in better agreement with relativistically corrected calculations. Certain unidentified lines in the spectra may be attributable to radiative transitions between quartet states of lithiumlike ions.

Pegg, D. J.↗
NASA NTRS1975

Development of high temperature resistant graphite fiber coupling agents

Surface treatments were investigated as potential coupling agents to improve the elevated temperature shear strength retention of polyimide/graphite and polyphenylquinoxaline/graphite composites. The potential coupling agents were evaluated by fiber strand tensile tests, fiber and composite weight losses at 533 and 588K, and by interlaminar shear strength retention at 533 and 588K. The two surface treatments selected for more extensive evaluation were a coating of Ventromer T-1, a complex organometallic reaction product of titanium tetrachloride and trimethyl borate, and a polyphenylquinoxaline (PPQ) sizing which was pyrolyzed in nitrogen to form a carbonaceous layer on the fiber. Pyrolyzed polyphenylquinoxaline is a satisfactory coupling agent for polyimide/Thornel 300 graphite fiber composites. During 1000 hours aging at 588K such composites lose a little over half their transverse tensile strength, and suffer a slight loss in flexural modulus. No degradation of flexural strength or interlaminar shear strength occured during 1000 hours aging at 588K. None of the coupling agents examined had a markedly beneficial effect with polyphenylquinoxaline composites.

Griffin, R. N.↗