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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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Nighttime F region molecular ion concentrations of oxygen and nobelium and associated nightglow morphology, using numerical method for solving nonlinear equations
Morphological relationships in solar chromospheric H alpha fine structure involving bushes, fibrils, threads and filaments
Lunar soil samples 12001,1, 12037, 12042,25 and 12070,100 exterior morphology and chemistry, noting environmental temperature decrease, crater formation and meteorite impact
Regular particle morphology and petrostatistics in Apollo 11 and 12 lunar fines and conglomerates, using phase contrast and scanning microscopes
Lunar glass spheres cratering origin hypothesis from target temperature effects on crater morphology in targets impacted by high velocity Al projectiles
The morphology of as-polymerized poly-p-xylylene grown between -17 and 30 C is found to consist of lame llar alpha crystals oriented with the (010) plane parallel to the support surface. The crystallinity decreases with decreasing polymerization temperature. Spherulitic and nonspherulitic portions of the polymer film consist of folded chain lamellas with the chain axis parallel to the support surface. The results were obtained by small- and wide-angle X-ray measurements, electron and optical microscopy, and differential thermal analysis.
Flares often begin near lines of zero-longitudinal magnetic field. These boundary lines between opposite polarities can have the magnetic field either parallel to or transverse to the boundary. A study of 75 flares associated with one or the other type of boundary indicates that the difference in boundary morphology is not reflected in the frequency or properties of the associated flares.
Reactions of various polymers, such as polystyrene and its stereo-specific isomers, butylrubber, nylon, etc., with nitrogen dioxide and sulfur-dioxide were studied over the past few years. More recently, work has been initiated on the influence of polymer morphology on degradation of polymers in presence of these gases, near UV radiation and oxygen. Unexpected effects have been observed during chain scission near room temperature. Thus, for instance, isotactic polystyrene of various crystallinities, as far as extent and type are concerned, show marked differences in their degradation characteristics. Thus, for instance, crystalline polymers show faster degradation than amorphous ones, which seems to be contrary to expectations. However, this phenomenon can be explained in quite a consistent manner. The importance of all these reactions in connection with air pollution is briefly discussed.
Morphology, provenance, and movement of desert sand seas in Africa, Asia, and Australia
A series of measurements from drifting stations, aircraft, the ERTS-1, Nimbus 4, and Nimbus 5 satellites have jointly provided a new description of the dynamics and morphology of the ice cover of the Beaufort Sea. The combined analysis of these data show that the eastern Beaufort Sea ice cover is made up of large multiyear floes while the western part is made of small, predominantly first-year floes. The analysis suggests that this distribution might be quasi-steady and that the dynamics and thermodynamics of the region are more complex than hitherto known. The measurements consist of: (1) high resolution ERTS-1 imagery which is used to describe floe size and shape distribution, short term floe dynamics, and lead and polynya dynamics; (2) tracking by Nimbus 4 of IRLS drifting buoys to provide ice drift information which enhances the interpretation of the ERTS-1 imagery; (3) Nimbus 5 microwave (1.55 cm wavelength) imagery which provides synoptic, sequential maps on the distribution of multiyear and first-year ice types; (4) airborne microwave surveys and surface based observations made during 1971 and 1972 in conjunction with the AIDJEX (Arctic Ice Dynamics Joint Experiment) program.
A description and classification of major types of sand seas on the basis of morphological pattern and lineation are discussed. The steps involved in analyzing the patterns of deposits on ERTS-1 imagery, where the visible forms are mostly dune complexes rather than individual dunes are outlined. After completion of thematic maps portraying the pattern and lineation of the sand bodies, data on directions and intensity of prevailing and other winds are plotted on corresponding bases, as a preliminary to determination of internal structures through ground truth.
The morphology of all silica materials studied has been noncrystalline and resistant to any phase transformations upon subsequent thermal testing representative of the shuttle environment envelope. The development of an extremely dependable reusable surface insulation material family offering the inherently superior characteristics of amorphous silica for the shuttle is described.
Conditions in a single pore of a battery plate were simulated by using a cadmium chip of millimeter dimensions covered with an electrolyte film of micron thickness. In situ microscopy was applied to study changes in the electrode morphology during charge and discharge. Passivation and increases in particle sizes due to precipitation and electrodeposition of dissolved cadmium species were found to cause profound loss in electrode capacity on repeated charge and discharge.
Statistical analysis of data from the auroral particles experiment aboard OGO 4, performed in a statistical framework interpretable in terms of magnetospheric substorm morphology, both spatial and temporal. Patterns of low-energy electron precipitation observed by polar satellites are examined as functions of substorm phase. The implications of the precipitation boundaries identifiable at the low-latitude edge of polar cusp electron precipitation and at the poleward edge of precipitation in the premidnight sector are discussed.
In order to study further the role of fluidization on the moon, a laboratory investigation was undertaken on two particulate material size fractions to determine the effect of variables, such as, duration of gas streaming, gas pressure, and 'regolith' thickness on the morphology of fluidization craters. A 3.175-mm cylindrical vent was used to simulate a gas streaming conduit. Details of the fluidization chamber are discussed together with questions of experimental control, aspects of nomenclature, crater measurements, and the effect of variables.
Review of the magnetospheric morphology, using the method of the Delta B topology, where Delta B is the difference between the observed and a reference field. It is confirmed that Delta B continuously decreases inward to close distances from the earth at all local times. Extrapolating the statistical relation between Dst at the ground and the equatorial Delta B obtained from OGO-5 near perigee, it is shown that Dst is 54 gammas, when Delta B is zero at approximately 2 to 3 earth radii. Conversely, for a magnetically quiet condition as defined by Dst = 0, the average equatorial Delta B at these distances is -45 gammas. These results demonstrate the significance of the effects of the magnetospheric equatorial current that exists even at quiet times. A preliminary study of inclination shows that the field lines on the dusk side are more stretched out than on the dawn side. A comparison of declination on both sides indicates that the bending of the field lines toward the tail is greater near dusk than near dawn. These results suggest an appreciable dawn-dusk asymmetry in the configuration of the inner magnetospheric field.
The present work is a test of published theoretical and experimental studies of crater erosion by micrometeorite bombardment which predict systematic variations in the morphology of lunar craters as a function of crater diameter and crater age. Numerical, ranking-type degradation classifications indicate that the craters on Mare Imbrium and Mare Tranquillitatis confirm these predictions by showing a systematic increase in degradation with decreasing diameter for craters smaller than a few kilometers in diameter but larger than the equilibrium diameter, and by showing fixed proportions of fresh, moderately degraded, and very degraded craters under equilibrium conditions. Furthermore, the relative ages of the two mare surfaces may be determined using a diameter/mean-degradation-number curve. These determinations of relative age and process of crater erosion are both essentially independent of the traditionally studied crater diameter/frequency relationships.
A brief description of the morphology of lunar surface material returned by Luna 16 automatic lunar station is given. Adhesiveness of the surface material and its ability to be electrified is noted. Two main genetic groups of regolith particles are differentiated: primary, represented mainly by fragments of magmatic rocks of the basalt and gabbro types, as well as mineralized grains of their constituent minerals, and secondary, particles subjected to appreciable exogenic transformation on the surface of the Moon. The second group, representing more than 70 percent of the material in coarse fractions, includes particles of breccias, sintered aggregates of complex dendritic form, and glass and vitrified particles of varied composition.