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Bass, A. M.

Publications and source records attributed to Bass, A. M..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1985

The ultraviolet cross-sections of ozone. I. The measurements. II - Results and temperature dependence

Absorption cross-sections of ozone have been measured over the range 230 nm to 350 nm, and for temperatures 200 K to 300 K, with improved photometric accuracy and spectral resolution. These measurements are referred to the cross-section at the 253.65 nm mercury line by the Hearn value (1961), 1147 x 10 to the -20th/sq cm, and show an internal consistency of + or - 1 percent. Tables of ozone absorption cross-section in the ultraviolet have been prepared for intervals of 0.05 nm over the range 245 to 340 nm. at each wavelength entry in the table a set of coefficients has been derived that permits the cross-section to be computed as a function of temperature, between 200 K and 300 K, with an accuracy of 1 percent.

Bass, A. M.↗
NASA NTRS1982

Anomalous atmospheric spectral features between 300 and 310 nm interpreted in light or new ozone absorption coefficient measurements

Real structure is revealed, by an analysis of continuous scan data from the solar backscattered UV instrument on Nimbus 7, in the backscattered atmospheric albedo region between 300 and 310 nm where spectral anomalies have been reported in ground-based observation. The spectral anomalies are explainable as structure at the 1-5% level in the ozone absorption coefficient, as measured by Bass and Paur (1981). The new absorption coefficient measurements are judged to approach the 1%-level of accuracy in atmospheric radiation calculation, which should resolve discrepancies between different Dobson wavelength pairs and between different instruments and permit the more accurate analysis of such second-order effects as NO emission, SO2 absorption in polluted atmospheres, and Raman scattering effects.

Mcpeters, R. D.↗
NASA NTRS1978

A new channel for the formation of hydrogen cyanide in CH2-N2 systems

The reaction between N2 and either the singlet or the triplet electronic state of CH2 is investigated in order to shed light on the formation of NO in fuel-rich hydrocarbon flames. For the reaction of N2 and the triplet CH2, a rate constant less than or equal to 10 to the minus 16th power cu cm/molecule-sec is obtained. The time history of hydrogen cyanide production from the CH2-N2 systems is discussed as a basis for understanding the possible reaction routes from HCN to NO.

Laufer, A. H.↗
NASA NTRS1976

Extinction coefficients of NO2 and N2O4

The extinction coefficient of NO2 has been measured in the spectral range from 185 to 410 nm as a function of temperature between 235 and 298 K. In order to correct for the effect of dimer absorption, the extinction coefficient of N2O4 has also been measured. The effect of a decrease in temperature on NO2 absorption is a reduction in the extinction coefficient of approximately 10% in the range from 320 to 380 nm.

Bass, A. M.↗
NASA NTRS1972

Ultraviolet atomic emission detector

A device and method are provided for performing qualitative and quantitative elemental analysis through the utilization of a vacuum UV chromatographic detector. The method involves the use of a carrier gas at low pressure. The gas carries a sample to a gas chromatograph column; the column output is directed to a microwave cavity. In this cavity, a low pressure microwave discharge produces fragmentation of the compounds present and generates intense atomic emissions in the vacuum ultraviolet. These emissions are isolated by a monochromator and measured by photometer to establish absolute concentration for the elements.

Braun, W.↗
NASA NTRS1971

A curve of growth determination of the f-values for the fourth positive system of CO and the Lyman-Birge-Hopfield system of N2.

The curve of growth method has been employed to determine f-values for the fourth positive system of CO and the magnetic dipole and electric quadrupole components of the Lyman-Birge-Hopfield system of N2. No significant dependence on r-centroid was found. The mean value of the ratio of the electric quadrupole to magnetic dipole f-values was 0.076.

Pilling, M. J.↗
NASA NTRS1970

Improved ultraviolet resonance lamp

Removal of the seal area from the path of the lamp discharge eliminates the gradual deterioration of lithium fluoride window surfaces from condensation of products formed by interaction of a resonant rare-gas discharge with window sealing materials. The discharge is confined to the inner tube.

Bass, A. M.↗