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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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At least 1,207 records · Page 67

Electrochemical catalysis.

Electrochemical and chemical catalysis differences due to applied field and solvent, discussing fuel cell reaction rates enhancement in electrochemical energy conversion

Bockris, J. O.↗

The fluorination of metals.

Elemental fluorine reactions with Ni, Cu, Fe, Ti, Be Al, Zr and Ag, giving reaction rate constants, activation energies, etc

Odonnell, P. M.↗

Inelastic molecular collisions

Collision cross sections direct measurement for determining macroscopic reaction rates in inelastic molecular collision processes in gas dynamics

Utterback, N. G.↗

Prediction of electron density in the boundary layer on entry vehicles with ablation

A rather general computer code has been developed for the numerical solution of the laminar boundary layer and thin shock layer (stagnation point only) equations for a multi-component gas mixture with finite reaction rates. The purpose of this paper is to indicate the capabilities of this computer program by presenting solutions for pure air flows and flows with carbon ablation. At the body surface the effects of oxidation and sublimation of carbon are taken into account with the following species included in the gas model: 0 2 , N 2 , O, N, NO, NO + , C 1 , C 2 , C 3 , CN, CO, and CO 2 . Results for the boundary layer along a 10° half-angle hyperboloid with ablation of carbon are compared to pure air results. Shock layer results for several wall temperatures and altitudes are presented and compared to pure air results. Other types of problems that can be solved with this computer code are indicated.

F. G. Blottner↗

Chemical kinetics computer program for static and flow reactions

General chemical kinetics computer program for complex gas mixtures has been developed. Program can be used for any homogeneous reaction in either one dimensional flow or static system. It is flexible, accurate, and easy to use. It can be used for any chemical system for which species thermodynamic data and reaction rate constant data are known.

Bittker, D. A.↗

NASA multidisciplinary research grant

Research is discussed in the multidisciplinary areas of space and planetary science; materials and radiation; systems, instrumentation, and structures; and technology and man. Highlights are identified as an alpha-recoil track method of archeological dating; infrared astronomical telescope; reaction rates data, semiconductor radiation detectors, and analysis of time-dependent systems; Gunn effect devices for microwave generation and detection, mode-locked lasers, and radiation theory; and the application of a satellite communication system to educational development. Detectors to be flown on Apollo 16 to measure heavy particle flux in the solar wind and to be part of the HEAO-A experiment on extremely heavy nuclei in cosmic rays were developed. The impact of the multidisciplinary research on university activities is described, and individual departmental reports are included.

Source record↗

Low-pressure oxidation of Cb-1Zr alloy.

Resistively heated strip specimens of Cb-1Zr alloy were exposed at 927 C in a vacuum chamber at various levels of total pressure in the 1-microtorr range and at various oxygen partial pressures in the .1-microtorr range. Oxygen reaction rates (sticking probabilities) were found to depend on whether or not the specimens were annealed immediately before the test exposure. It is shown that a normally undetectable oxide film exists on the Cb-1Zr surface as a result of oxidation by ambient air, and this film reduces the sticking probability as compared with a clean metal surface. The alloy is considerably strengthened by addition of oxygen to a level of about 6000 ppm, while still maintaining reasonably good room temperature ductility.

Lyon, T. F.↗

Positive ion chemistry of the D and E regions.

A comparison of ion-molecule reaction rates implied by E- and F-region chemistry and measured in the laboratory shows on the whole good agreement except that the ionospheric analysis demands stronger temperature dependences. In the daytime D region, it is claimed that the reconciliation of positive ion densities with production rates and laboratory rate constants would best be achieved if (1) ionization of O2(1 delta g) and hydration of O4(+) in competition with the reduction of O4(+) to O2(+) by O were the dominant source of hydrates between 85 and 77 km, (2) ionization of NO by solar Lyman alpha followed by hydration was the dominant source of hydrates below 77 km, and (3) for some reason, Lyman alpha did not ionize NO effectively at pressures below those prevailing at 75 km.

Donahue, T. M.↗