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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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Urine osmolality of centrifuged rats compared with ad libitum or pair-fed control animals, indicating enhanced free water excretion and antidiuretic hormone involvement
Disturbances of vestibular origin comprising motion sickness resulting from rotating tilted chair
Microorganism survivability in desert algal soil crust under continuous very high vacuum
Voltage breakdown threshold of electronic equipment in partial pressure environment of nitrogen and water vapor
Tilting rotating chair producing vestibular stimulus via linear rotating acceleration to study motion sickness
Compression effects in air-oxygen mixture on male mice, observing no adversity on mortality, growth and nitrogen content
Balloon-borne monkeys possible brain damage due to cosmic rays, discussing thindown tracks and acute vasculitis
Airborne microwave radiometric sensing of volcanic surface area
Structural response and acoustic transmission characteristics of glass pane and standard wood frame construction wall panels subjected to sonic booms
Noctilucent cloud particle size composition and origin from sounding rocket flight and control collecting surfaces
Thermal stress distribution and temperature profiles in nearly opaque spherical shell under radiant and convective heating flux
Hot-spot and puncture ignition of fuel vapors by simulated lightning discharges was studied experimentally. The influences of skin coating, skin structure, discharge polarity, skin thickness, discharge current level, and current duration were measured and interpreted. Ignition thresholds are reported for titanium alloy constructed as sheets, sheets coated with sealants, and sandwich skins. Results indicated that the ignition threshold charge transfer for coated sheets, honeycomb, and truss skins is respectively about 200%, 400%, 800% that of bare alloy sheet of .102 cm (.040 in.)-thickness. It was found that hot-spot ignition can occur well after termination of the arc, and that sandwich materials allow ignition only if punctured.
Investigation of the problem of whether morphological changes occurring in the central nervous system (CNS) following whole-body irradiation are attributable in part to abscopal factors. The 12 monkeys irradiated and the 6 that served as controls were chosen from a pool of 25 young monkeys. Over the postirradiation survival period of 14 days the hematocrit and hemoglobin values varied only slightly from the baseline values and from the values in the 6 control animals. White cell fractions were reduced in quantity but tended to recover relatively soon after irradiation. The design of this experiment was regarded as adequate to allow a conclusion whether pathological changes in the CNS of the irradiated animals differed from or exceeded those observed in the control animals. That such occurred on both counts in 3 of the 12 irradiated animals was evident. It appears that all the lesions must have been abscopally induced.
Cultures of B. thuringiensis returned from space flight appeared to be normal to slightly affected adversely in their ability to produce three toxins that affect insects. In addition, it can be stated that B. thuringiensis spores are very resistant to ultraviolet irradiation at the individual wavelengths and energy levels previously described. Full sunlight, however, does have a detrimental effect on the viability of B. thuringiensis spores.
The Thermal Control Coatings Experiment flown on OSO 3 in the near-earth space environment was designed to measure changes in the solar absorptance and IR emittance of selected test coatings. The present work describes results obtained from four years in orbit. Changes in solar absorptance of the coatings are illustrated as a function of equivalent sun hours, and it is seen that five of eleven coatings considered exhibit no change in solar absorptance over four years or 7500 equivalent sun hours. The effects of micrometeoroids on polished metal surfaces are judged to be negligible for a near-earth mission of four years.
Auger electron spectroscopy measurements performed on Skylab 2 indicate a low rate of deposition of permanent, continuous film contamination on nickel and gold surfaces positioned on the antisolar side of the spacecraft. These measurements and supportive evidence indicate that for the particular locations and orientations of these samples permanent films of less than 3 nm (30 A) thickness were deposited during an exposure of 40 hours at a temperature of approximately -32 C.
Experimental results of a series of engine tests designed to obtain the stage dynamics of an eight-stage axial-flow compressor over the frequency range of 0.5 to 200 hertz are presented. The total pressure at the compressor face was varied by means of a secondary air jet system installed in the engine inlet and positioned to oppose the primary airflow. Total-pressure probes located at each compressor stage were used to obtain the frequency response of each compressor-stage total pressure to the average compressor-inlet total pressure. The engine operating conditions were chosen to illustrate the effects of changing the rotor speed, changing the exhaust nozzle area, and isolating the compressor discharge pressure perturbations from the fuel control and hence, the fuel flow.
The saccules of 15 centrifuged rats and 15 control rats were examined for morphological alterations resulting from long-term exposure to hypergravity. Minimal changes were found confined to the otolithic membrane. They were a slight decrease in the overall volume of otolithic membrane, a redistribution of otoconia in the direction of the gravitational force, and a more pronounced 'accessory' membrane. These changes were interpreted as purely mechanical effects of hypergravity, causing accelerated displacement of otoconia and subsequent entrapment of some of them on inferior portions of the primary otolithic membrane and 'accessory' membrane.