Low energy mosaic electron sensor.
Low energy electron position detection with composite surface barrier type diode, noting design, fabrication and operation
ELECTRON GUN↗
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Results for “surface composition”
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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Principal scientific results
Surveyor 5 measurements of chemical elements and magnetic properties of lunar surface composition
Batterson, S. A.↗
Preliminary scientific results from the U.S. Surveyor lunar probe
Surveyor 1 and 5 data on lunar surface composition and consistency, discussing Luna and Ranger projects of U.S.S.R. and U.S.
Koehler, H. W.↗
Some topics in electrocatalysis
Liquid metal alloys surface composition and electronic structure roles in electrocatalysis evaluated by studying hydrogen-ion discharge reaction and electrical double layer
Butler, J. N.↗
Surface structure of ammonium perchlorate composite propellants
Burning solid ammonium perchlorate composite propellants surface structure observation to assess heterogeneous or subsurface reactions, using scanning electron microscope
Beckstead, M. W.↗
Results of recent manned and unmanned lunar exploration
Lunar exploration by manned and unmanned space flights, discussing seismology, composition, surface features, etc
Jaffe, L. D.↗
Mars - The spectral albedo /0.3-2.5 microns/ of small bright and dark regions
Mars IR spectral geometric albedo of bright and dark regions for surface composition model
Elias, J. H.↗
Hot-salt stress-corrosion of titanium alloys as related to turbine engine operation.
Demonstration that the major variables influencing hot-salt stress-corrosion of titanium alloys are alloy processing conditions, heat-to-heat variations and composition, surface condition, and cyclic exposures. Under simulated compressor environmental conditions the commonly used 64 alloy is creep limited and not stress-corrosion limited. Cyclic exposures to stress-corrosion conditions are not as detrimental as continuous exposures for equivalent total times.
Gray, H. R.↗
Variations in the detectability of major airports in northeastern Kansas and northwestern Missouri
The author has identified the following significant results. Six major airports are located within the ERTS-1 imagery. Runways at four of the airports are readily detectable. Runways at the other two airports are not detectable and the locations must be inferred by other means. This variation is attributed to variation in runway surface composition.
Morain, S. A.↗
Effect of surface catalytic activity on stagnation heat-transfer rates.
An experiment was made to determine the effect heterogeneous catalytic surface reactions have on heat-transfer rates in highly frozen low-density stagnation-point boundary layers. Data were obtained in arc-heated facilities that were capable of producing large percentages of chemical energy frozen in a supersonic freestream. The heat-transfer rate to a silicon-dioxide surface was reduced to a minimum value of only one-third of the value obtained on relatively active nickel and platinum surfaces. This is the result of its low catalytic efficiency. Ionization energy was recovered on both the active and the inactive surfaces, indicating that this energy either was released many times faster than the recombination energy or was not controlled by the surface composition.
Anderson, L. A.↗
ALSEP arrays A, B, C, and A-2
The objectives of the lunar surface exploration packages are defined and the preliminary design of scientific systems hardware is reported. Instrument packages are to collect and transmit to earth scientific data on the lunar interior, the lunar surface composition, and the lunar geomorphology
Source record↗
The Nimbus 5 data catalog. Volume 1: Data orbits 104 through 693, 19 December 1972 - 31 January 1973
Nimbus 5 was successfully launched from the Western Test Range at Vandenburg AFB, California, into a near circular orbit (1089 km x 1102 km) at 07 hr 56 min 00 sec GMT on 11 December 1972. All experiments and subsystems were successfully turned on. Satellite operations from launch (11 December) through orbit 103 (18 December) consisted of engineering evaluation of all spacecraft systems. As a result of that effort, data reception, accountability, and processing were intermittent during that period. Therefore, this catalog reflects documentation from orbit 104 (19 December 1972) through orbit 693 (31 January 1973). The pitch bias history, surface composition mapping radiometer, and infrared temperature profile radiometer are discussed.
Source record↗
On the properties of matter in neutron stars
A qualitative description of the interior of a neutron star is presented, giving attention also to the validity of the 'isotropic fluid' approximation. The atmosphere and surface of a neutron star are considered together with aspects concerning nuclear and solid state physics in the crust, the liquid interior, the hyperon core, neutron star models, and pulsar observations. Accretion processes are also investigated, taking into account such topics as the Eddington limit, accretion rates, the death of pulsars, changes of the surface composition of neutron stars by accretion, questions of X-ray emission, and aspects of gamma radiation emission.
Boerner, G.↗
An X-ray photoelectron spectroscopy study of nickel and nickel-base alloy surface alterations in simulated hot corrosion conditions with emphasis on eventual application to turbine blade corrosion
The spectra of the pure metals tested and their oxides were used to analyze the patterns obtained for various superalloys. The quantitative results for two superalloys revealed differences between the surface compositions and their behavior under different conditions of oxidation. The following results occurred during the hot corrosion of samples in the presence of Na2So4: a lack of Ti migration; strong effects on Cr; and, a higher speed of alteration of superalloys.
Mateescu, G. D.↗
The science of the Viking missions
The Viking missions involve the launching of two identical spacecraft in the summer of 1975. Each spacecraft consists of a Lander and an Orbiter combination. The initial deceleration of the Lander during its descent to the Martian surface will be caused by aerodynamic drag. At about 5 km above the surface, a parachute is deployed. At 2 km three retrorockets are fired. The investigations to be conducted are discussed, giving attention to studies of the Martian surface with the aid of TV cameras, water mapping with an IR spectrometer, a thermal mapping experiment, studies of the Martian atmosphere, investigations conducted with a surface sampler, the search for life, and studies of the Martian surface composition.
Soffen, G. A.↗
Asteroids - Spectral reflectance and color characteristics
We present visible and near-infrared spectral reflectance curves for 35 asteroids, making a total sample of 67 including our previous work. Several previously unknown spectral types have been discovered. Absorption bands and other features, from which information about the surface composition of the asteroids can be derived, continue to appear. Sampling statistics suggest we have observed about half of the significantly different mineralogical assemblages present in the asteroid belt. There is a general, but imperfect, correlation between spectral type and semimajor axis, which is consistent with the hypothesis that meteorites are derived from the asteroid belt. The color-frequency histogram for the 67 objects is bimodal, probably associated with 'stony' objects and 'carbonaceous' objects. Hirayama family pairs usually show disparate spectral types. 19 Fortuna may show strikingly different photometric properties on opposite sides.
Mccord, T. B.↗
Surface properties of asteroids - A synthesis of polarimetry, radiometry, and spectrophotometry
Surface compositions of 110 asteroids are analyzed using data obtained by polarimetry and visible and near-IR spectrophotometry. A comparison of albedos and diameters determined by polarimetry and radiometry indicates that a slight upward revision of the radiometric albedo scale is necessary. Reliable adopted albedos and diameters are presented for 56 objects, and rough diameters are obtained for 52 additional objects. More than 90% of the asteroids are shown to fall into two broad groups (C and S) which are compositionally similar to carbonaceous and stony meteorites, respectively. C-type asteroids are found to predominate in the asteroid belt, and the largest of these (Ceres, Pallas, Hygiea, Davida) may be metamorphosed. It is shown that Vesta may be the only differentiated asteroid remaining intact in the belt. The results support the conclusions that asteroids and meteorites have similar classes of mineral assemblages, but the distribution of asteroid types contrasts with the distribution of major meteorite types found on earth.
Chapman, C. R.↗
On the kinetics of pack aluminization
A theory of pack aluminization has been formulated by combining gaseous and solid-state diffusion rates. This theory relates the surface composition of the coating and therefore, in principle, the phase morphology and the growth rate of the coating, to pack operating parameters such as pack aluminum density, type of activator, temperature and others. Experimental data on the aluminization of unalloyed nickel in pure aluminum packs obtained to date are in good agreement with the predictions of the theory.
Gupta, B. K.↗