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Wechsler, A. E.

Publications and source records attributed to Wechsler, A. E..

16 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Research study on materials processing in space Skylab experiment M553 - sphere forming

A research program was conducted to study the solidification of metals in the form of small spheres both in the one gravity environment of the earth laboratory and the low gravity environment of KC-135 trajectory flights and the Skylab 1/2 mission. The program had three phases. The details of the results of this program are contained in interim reports prepared at the conclusion of each of the three phases. This final report is intended to summarize the efforts and results described in detail in each of these interim reports, with particular emphasis on the differences observed between the ground-based and Skylab flight specimens.

Johnson, P. C.↗
NASA NTRS1972

Biological cycling of atmospheric trace gases

A detailed critical review was conducted of present knowledge of the influence of biological processes on the cycling of selected atmospheric gas constituents--methane, carbon monoxide, and gaseous compounds of nitrogen (nitrous oxide, ammonia, nitric oxide, and nitrogen dioxide) and sulfur (hydrogen sulfide and sulfur dioxide). The identification was included of biological and other sources of each gas, a survey of abundance measurements reported in the literature, and a review of the atmospheric fate of each contituent. Information is provided on which to base conclusions regarding the importance of biological processes on the atmospheric distribution and surface-atmosphere exchange of each constituent, and a basis for estimating the adequacy of present knowledge of these factors. A preliminary analysis was conducted of the feasibility of monitoring the biologically influenced temporal and spatial variations in abundance of these gases in the atmosphere from satellites.

Hitchcock, D. R.↗
NASA NTRS1972

Heat flow experiment

The heat flow experiment installed on the lunar surface during the Apollo 15 flight is described. Subjects discussed are: (1) the experiment concept and design, (2) the operations of the experiment, (3) the employment of the experiment on the lunar surface at Hadley Rille site, (4) subsurface lunar temperatures, and (5) extrapolation of sensor temperatures to equilibrium values. Graphs of the data obtained from the experiment are provided.

Langseth, M. G., Jr.↗
NASA NTRS1972

Thermal properties of granulated materials.

Review of the thermophysical properties of granular materials or silicates believed to simulate the lunar surface layer. Emphasis is placed on thermal conductivity data and the effects of material and environmental variables on the thermal conductivity. There are three basic mechanisms of heat transfer in particulate materials: conduction by the gas contained in the void spaces between the particles; conduction within the solid particles and across the interparticle contacts; and thermal radiation within the particles, across the void spaces between particle surfaces, and between void spaces themselves. Gas and solid conduction, thermal radiation, and the interaction between conduction and radiation are considered.

Wechsler, A. E.↗
NASA NTRS1970

Apollo 13 lunar heat flow experiment

Apollo 13 lunar surface heat flow experiment to measure vertical temperature gradients as function of time and soil thermal conductivity

Chute, J., Jr.↗
NASA NTRS1968

Thermal conductivity and dielectric constant of silicate materials

Report on the thermal conductivity and dielectric constant of nonmetallic materials evaluates the mechanisms of heat transfer in evacuated silicate powders and establishes the complex dielectric constant of these materials. Experimental measurements and results are related to postulated lunar surface materials.

Simon, I.↗
NASA NTRS1967

Experiments to investigate particulate materials in reduced gravity fields

Study investigates agglomeration and macroscopic behavior in reduced gravity fields of particles of known properties by measuring and correlating thermal and acoustical properties of particulate materials. Experiment evaluations provide a basis for a particle behavior theory and measure bulk properties of particulate materials in reduced gravity.

Bowden, M.↗