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Silicon oxide films coated satellite aluminum surfaces solar absorptivity and thermal emissivity, noting suitability as temperature control coatings
Method extends scope of ion plating technique to include deposition of alloy films without changing composition of plating alloy. Coatings flow with specimen material without chipping or peeling. Technique is most effective vacuum deposition method for depositing alloys for strong and lasting adherence.
Vaporization caused by incipient boiling in forced convective flow of superheated liquid
Device for high vacuum film deposition with electromagnetic ion steering
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Remote sensing by means of stereo images obtained from flown cameras and scanners provides the potential to monitor the dynamics of pollutant mixing over large areas. Moreover, stereo technology may permit monitoring of pollutant concentration and mixing with sufficient detail to ascertain the structure of a polluted air mass. Consequently, stereo remote systems can be employed to supply data to set forth adequate regional standards on air quality. A method of remote sensing using stereo images is described. Preliminary results concerning the planar extent of a plume based on comparison with ground measurements by an alternate method, e.g., remote hot-wire anemometer technique, are supporting the feasibility of using stereo remote sensing systems.
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It is shown that the fields of velocity, eddy viscosity, potential temperature, and specific humidity in a planetary boundary layer are decoupled by the introduction of a free parameter, Q, which combines the effects of thermal and humidity stratification. Solutions of the whole system are shown to be obtainable by the method of trial and error on Q. Results show good agreement when both the thermal and humidity stratification are accounted for.
Measurements were made of the isothermal adsorption-desorption kinetics for H2 chemisorbed onto Fe films. The chemisorption process is observed to proceed via a precursor state of adsorbed molecular hydrogen similar to the H2-Ni system. The first measurements of the activation energy for desorption, and estimates of the values of the fast kinetic rates between the precursor and chemisorbed states are reported. Adsorption into the precursor state does not appear to be activated, but the process connecting the precursor state with the chemisorbed state will, under certain circumstances, be a rate limiting step for adsorption. The effects of contamination of the surface are evidenced in the measurements.
An investigation is conducted of the kinetics of isothermal adsorption-desorption processes involving molecular hydrogen which is chemisorbed onto thin (20 to 50 A) polycrystalline Fe films at temperatures near 300 K. The results of the investigation indicate that chemisorption in the H2-Fe system occurs via a precursor state of molecularly adsorbed hydrogen. Contamination of the surface from unknown impurities in the gas phase is found to affect the number of available adsorption sites and to modify the prefactor for the absolute desorption rate constant for the precursor state.
Postperihelion narrow-band filter photometry has been used to derive gas and dust production rates for Comet West. For heliocentric distances less than 1.25 AU, C2 and CN vary as the -2.8 power of distance, while C3 and OH (based on published measurements) vary as -2.1 power. C3 production closely parallels dust production. It is concluded that OH and C3 parents are produced at the nucleus, while CN and C2 parents are produced from the icy-grain halo. It is also found that Comet West is one of the dustiest and most productive of the recent comets, being exceeded only by Comet Bennett.
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Films of copper molybdenum sulfide were produced by coevaporation. Those that were superconducting contained only the ternary compound and free molybdenum. The range of copper content in the ternary compound was as large as that in polycrystalline material, that is, it includes either phase alone, or a mixture of the two phases of this material. This is in contrast with sputtered materials where copper concentration has been limited to a narrower range. The upper critical field and the critical current were measured as functions of external magnetic field, and found to be similar to those of sputtered copper molybdenum sulfide, when the comparison was made for samples having the same amount of copper.
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