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Results for “GAS SPECTROSCOPY”

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 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
NASA NTRS1966

Electron beam diagnostics.

Spectroscopic electron beam diagnostic technique, examining negligible effect elevated vibrational temperatures have on measured rotational temperatures of molecular nitrogen

ELECTRON BEAM↗
NASA NTRS1966

The spectrum of N IV.

Spectrum of three-times ionized nitrogen analyzed in wavelength region 300-8000 angstroms, using theta pinch discharge, connecting singlets and triplets

IONIZED GAS↗
NASA NTRS1972

An etiological study of phthalate self-contamination of spacecraft and contamination from their earthly environs

Phthalates are very objectionable contaminants in space experiments because of their strong absorption in the UV and IR regions of the spectrum. Thus, even minute amounts of these compounds migrating to optical equipment, in test or space flight conditions, can seriously compromise the results of experiments by altering the sensitivity of the functional equipment. Volatility data of the phthalates and other plasticizers are presented in addition to UV spectra of ultrathin films of these same types of compounds. Sources of plasticizer contamination are revealed with special recognition given to di-2-ethylhexyl phthalate (DEHP), the single most ubiquitous plasticizer in use. A surprisingly large percentage of the outgassing condensates from vacuum testing of spacecraft contain DEHP as well as other plasticizers. IR and gas chromatography/mass spectroscopy methods were used to analyze samples from spacecraft. Methods for successful reduction of plasticizers and other contaminants are mentioned.

Gross, F. C.↗
NASA NTRS1984

Acoustically-induced modulation spectroscopy for ultra-sensitive gas analysis

A new optical technique has been developed for ultra-sensitive attenuation measurements in gaseous media and, in particular, for determination of low levels of smoke emitted from jet engines. It is a variation on direct light transmission where the sample gas density in a cell is modulated acoustically by a speaker. The amplitude variation of the light transmission is proportional to the gas density and is insensitive to window contamination and detector instabilities. Preliminary analysis and experiments indicate that the instrument promises to measure light absorption to less than 1 percent per meter and allow measurment of smoke emissions from 1 to 100 mg/cu m. The technique has been demonstrated through the use of an absorbing gas, viz., 200 ppm of NO2 in N2 which produces 25 percent per meter absorption.

Pitz, R. W.↗
NASA NTRS1984

Theoretical research program to study transition metal trimers and embedded clusters

Small transition metal clusters were studied at a high level of approximation, including all the valence electrons in the calculation and extensive electron correlation, in order to understand the electronic structure of these small metal clusters. By comparison of dimers, trimers, and possibly higher clusters, the information obtained was used to provide insights into the electronic structure of bulk transition metals. Small metal clusters are currently of considerable experimental interest and some information is becomming available both from matrix electron spin resonance studies and from gas phase spectroscopy. Collaboration between theorists and experimentalists is thus expected to be especially profitable at this time since there is some experimental information which can serve to guide the theoretical work.

Walch, S. P.↗