Ambient formaldehyde detection with a laser spectrometer based on difference-frequency generation in PPLN

Rehle, D.; Leleux, D.; Erdelyi, M.; Tittel, F.; Fraser, M.; Friedfeld, S.

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NASA NTRS · 20040087933

Ambient formaldehyde detection with a laser spectrometer based on difference-frequency generation in PPLN

Rehle, D.·Leleux, D.·Erdelyi, M.·Tittel, F.·Fraser, M.·Friedfeld, S.

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Abstract

A laser spectrometer based on difference-frequency generation in periodically poled LiNbO3 (PPLN) has been used to quantify atmospheric formaldehyde with a detection limit of 0.32 parts per billion in a given volume (ppbV) using specifically developed data-processing techniques. With state-of-the-art fiber-coupled diode-laser pump sources at 1083 nm and 1561 nm, difference-frequency radiation has been generated in the 3.53-micrometers (2832-cm-1) spectral region. Formaldehyde in ambient air in the 1- to 10-ppb V range has been detected continuously for nine and five days at two separate field sites in the Greater Houston area operated by the Texas Natural Resource Conservation Commission (TNRCC) and the Houston Regional Monitoring Corporation (HRM). The acquired spectroscopic data are compared with results obtained by a well-established wet-chemical o-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine (PFBHA) technique.

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NASA Discipline Life Sciences Technologies Non-NASA Center Spectrophotometry, Infrared/instrumentation Lasers Atmosphere/chemistry Environmental Monitoring/instrumentation Formaldehyde/analysis Texas Niobium Evaluation Studies Ozone/analysis/chemistry Support, U.S. Gov't, Non-P.H.S Oxides Equipment Design Time Factors Signal Processing, Computer-Assisted Support, Non-U.S. Gov't

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Rehle, D., Leleux, D., Erdelyi, M., Tittel, F., Fraser, M., Friedfeld, S.. 2001-01-01. Ambient formaldehyde detection with a laser spectrometer based on difference-frequency generation in PPLN. https://ntrs.nasa.gov/citations/20040087933

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