Field intercomparison of a novel optical sensor for formaldehyde quantification

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

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NASA NTRS · 20040088590

Field intercomparison of a novel optical sensor for formaldehyde quantification

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

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Abstract

A one-week in situ intercomparison campaign was completed on the Rice University campus for measuring HCHO using three different techniques, including a novel optical sensor based on difference frequency generation (DFG) operating at room temperature. Two chemical derivatization methods, 2,4-dinitrophenylhydrazine (DNPH) and o-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine (PFBHA), were deployed during the daylight hours for three- to four-hour time-integrated samples. A real-time optical sensor based on laser absorption spectroscopy was operated simultaneously, including nighttime hours. This tunable spectroscopic source based on difference frequency mixing of two fiber-amplified diode lasers in periodically poled LiNb03 (PPLN) was operated at 3.5315 micrometers (2831.64 cm 1) to access a strong HCHO ro-vibrational transition free of interferences from other species. The results showed a bias of -1.7 and -1.2 ppbv and a gross error of 2.6 and 1.5 ppbv for DNPH and PFBHA measurements, respectively, compared with DFG measurements. These results validate the DFG sensor for time-resolved measurements of HCHO in urban areas.

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NASA Discipline Life Sciences Technologies Non-NASA Center Formaldehyde/analysis Atmosphere/chemistry Environmental Monitoring/instrumentation/methods Spectrum Analysis/instrumentation/methods Hydroxylamines Support, U.S. Gov't, Non-P.H.S Evaluation Studies Comparative Study Darkness Optics Phenylhydrazines Lasers Support, Non-U.S. Gov't

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Friedfeld, S., Fraser, M., Lancaster, D., Leleux, D., Rehle, D., Tittel, F.. 2000-07-15. Field intercomparison of a novel optical sensor for formaldehyde quantification. https://ntrs.nasa.gov/citations/20040088590

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