HR: 1340h
AN: A43C-0071    [Abstracts]
TI: Measurement of Atmospheric Formaldehyde by Laser-Induced Fluorescence
AU: * Case, A T
EM: acase@eas.gatech.edu
AF: Georgia Institute of Technology, School of Earth and Atmospheric Sciences 311 Ferst Dr, Atlanta, GA 30332
AU: Hecobian, A
EM: ahecobian@eas.gatech.edu
AF: Georgia Institute of Technology, School of Earth and Atmospheric Sciences 311 Ferst Dr, Atlanta, GA 30332
AU: Mastromarino, J
EM: opodude@yahoo.com
AF: Georgia Institute of Technology, School of Earth and Atmospheric Sciences 311 Ferst Dr, Atlanta, GA 30332
AU: Tan, D
EM: dtan@eas.gatech.edu
AF: Georgia Institute of Technology, School of Earth and Atmospheric Sciences 311 Ferst Dr, Atlanta, GA 30332
AB: The development of a laser-induced fluorescence (LIF) formaldehyde (HCHO) detection instrument capable of measuring parts-per-trillion-by-volume (pptv) levels of formaldehyde in ambient air is presented. This instrument is part of a multispecies detection system designed to measure a variety of species (the other species in this initial version are NO and NO$_2$) important to photochemistry and atmospheric composition in a compact, robust package suitable for airborne and other field measurements. A preliminary version was deployed on the Intercontinental Chemical Transport Experiment - North America (INTEX-NA) in the summer of 2004. This approach employs excitation of the lowest-lying electronic state of formaldehyde along the A$^1$A$_2$ $\leftarrow$ X$^1$A$_1$ transition at 353.16 nm and measurement of fluorescence in the 400-450 nm range. The instrument samples ambient air at reduced pressure in a White cell and operates at kHz pulse repetition frequencies. We have identified no significant chemical interferences for this measurement scheme.
DE: 0317 Chemical kinetic and photochemical properties
DE: 0365 Troposphere--composition and chemistry
DE: 0394 Instruments and techniques
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting