Accession Number : ADA183421

Title :   Kr+ Laser Excitation of NH2 in Atmospheric Pressure Flames.

Descriptive Note : Final rept. Jan 84-Oct 85,

Corporate Author : ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD

Personal Author(s) : Anderson,William R ; Vanderhoff,John A ; Kotlar,Anthony J ; Wong,Koon N

PDF Url : ADA183421

Report Date : 13 Apr 1987

Pagination or Media Count : 38

Abstract : Fluorescence in the A-X system of the NH2 radical has been excited in NH3/N2O/N2, H2/N2O/N2 and CH4/N2O/N2 flames using the 6471A line of a krypton ion laser. Trace species in the H2/N2O/N2 flame are of interest because reactions which take place in this flame are expected to be a subset of the gas phase reactions in the combustion of propellants. Detection of NH2 fluorescence was found to be very simple to implement using the krypton laser. Rotationally resolved fluorescence spectra indicate that the laser simultaneously pumps two rotational lines in the (0,11,0)-(0,2,0) vibrational hot band of the radical. The placement of the laser line relative to the two molecular transitions has been inferred from intensities in the fluorescence spectrum. Rotational and vibrational energy transfer in the excited state were observed to be very slow in comparison to electronic quenching by the flame molecules. An NH2 density profile in a rich H2/N2O/N2 flame is given. Also, a method for the calculation of Einstein coefficients and oscillator strengths for nonperturbed, main-branch transitions is presented. Keywords: Methane, Laser Induced Fluorescence, Combustion, Radical, Ammonia, Absolute Intensities, Flame, Nitrous Oxide, Hydrogen.

Descriptors :   *FLAMES, *AMMONIA, *KRYPTON, *LASERS, AMMONIA, BAND SPECTRA, BAROMETRIC PRESSURE, COMBUSTION, ELECTRONICS, ENERGY TRANSFER, FLAMES, FLUORESCENCE, GASES, HIGH TEMPERATURE, HYDROGEN, INTENSITY, IONS, KRYPTON, LASER INDUCED FLUORESCENCE, LASERS, METHANE, MOLECULAR PROPERTIES, MOLECULES, NITROUS OXIDE, OSCILLATORS, PROPELLANTS, QUENCHING, SPECTRA, STRENGTH(GENERAL), TRANSITIONS, VIBRATIONAL SPECTRA

Subject Categories : Inorganic Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE