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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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Organic synthesis processes, which may have occurred in the primitive earth atmosphere or in comets, produced in the laboratory by methods of electric discharge, uv light and ionizing radiation
Components for a high-reliability system such as the Telstar project are obtained by: (a) design of the component for the required environment, (b) careful control of manufacturing processes, (c) elimination of potential early failures by screening tests, and (d) selection of the most stable components. For passive components, these methods could be applied by using design parameters, suppliers and screening techniques established in the earlier submarine cable program, with consideration being given to the additional effects of the satellite launch and orbit environments. Semiconductor component designs were selected by qualification tests using accelerated electrical and environmental stress conditions. Screening tests were applied to eliminate early failures, and resulting components were aged from two to six months before selection for the satellite. The recognition of the effect of ionizing radiation on transistors caused the addition of a radiation qualification test, or a screening to assure selection of the least sensitive devices. Tests have shown this screening to be effective for the radiation intensity expected. Experience with the passive components, and evaluation of the accelerated test results and aging data of the semiconductor devices, indicate that the reliability objective was obtained.
Vacuum technology, meteoroids, magnetic fields, electromagnetic radiation, and ionizing particles - conference on role of simulation in space technology
General radioactive isotope information, stressing radioactivity, methods of measurement, and dosimetry of radioactive nuclides have been reviewed to serve as a reference for the medical profession. Instability of radionuclides, principal types of emission, and measurement of ionizing radiation are among the topics discussed.
Effects of ionizing radiation on the amino acids of proteins and the reactivity of the protonated amino group depends upon the pK subscript a of the group. Estimates of the rate constants for reactions involving the amino acid side chains are presented. These rate constants gave an approximate rate constant for three different protein molecules.
Current research, both theoretical and experimental, relating to the production and kinetics of interactions of solvated electrons is reviewed. Particular attention is focused on solvated electrons generated by ionizing radiation in water, alcohols, and organic systems.
Human responses to aerospace environment in relation to microwave, light, thermal, and ionizing radiation
Synergistic effects of prolonged heat exposure and whole body irradiation with ionizing radiation on survival time in hamsters
D region ionizable constituent density /presumably nitric oxide/ measured, using blunt probe to detect changes in conductivity produced by Lyman alpha ionizing radiation
Equilibrium velocity distributions of F region photoelectrons produced by solar ionizing radiation, discussing dayglow as impact result
Advantages and problems of preserving food with ionizing radiation
High voltage cable for use in high intensity ionizing radiation fields
Assembly pumps liquid sodium-potassium /NaK/ eutectic at 950 K for up to 20,000 hours. Design features include - high operating-temperature capability, zero leakage, process fluid lubricant/coolant, insulation system compatible with ionizing radiation environments, and reliability and long life without maintenance.
Ionized gas galactic cluster stabilization model construction, considering ionizing radiation enhanced cosmic flux and quasar PKS 1116 plus 12 absorption spectrum
E and F region positive ion composition, electron concentration and thermal balance vertical profile, discussing ionizing radiation spectrum, plasma cooling, primary chemical reaction rates and ionospheric formation
An experimental determination of the optical transmission of Corning 7940 UV and Suprasil I fused silica has been made. The LeRC dynamitron provided the equivalent ionizing radiation and high temperature that the transparent gas divider of an operating nuclear light bulb engine would experience. The irradiation induced absorption was measured at 2150 A, 2700 A, and 4500 A. The length of the irradiations were sufficient so that an equilibrium between radiation induced coloration and high temperature annealing was reached. The experimental results indicate a significant optical absorption, particularly at the shorter wavelength, which would make the use of fused silica in this concept questionable.
Investigation of impurity-related electron-hole traps that are known to be sensitive to ionizing radiations. Electron spin resonance (ESR) equivalent natural doses were determined for the Al hole trap in virgin specimens; the doses agreed with estimates based on published data for the Ge electron trap. The 0.17 deg/sec 180 and 300 C thermoluminescence (TL) peaks in natural specimens were found to have activation energies approximately correct for the Ge trap. The 300 C peak was also found to be correlated with annealing of the Ge electron resonance in gamma-irradiated, step-annealed specimens. Although the 300 C peak occurs in virgin specimens, the corresponding natural Ge electron resonance was not observed.
Detailed study of the observed ionospheric effects of the X-ray flare on July 8, 1968, which was of considerable importance both from the ionospheric and solar physics point of view. The associated optical flare was of importance 3B. The ionospheric effects were examined in order to derive a suitable physical model of flare-induced ionization below 100 km, and hence to estimate the spectral characteristics of the ionizing radiations from the observed SID s. The electron loss coefficients below 70 km height calculated from the formula developed in the analysis are in agreement with available data.