Photoacoustic spectroscopy of formaldehyde with tunable laser radiation at the parts per billion level
Autor: | András Miklós, Peter Hess, M. Angelmahr |
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Rok vydání: | 2006 |
Předmět: |
Detection limit
Materials science Physics and Astronomy (miscellaneous) business.industry General Engineering Analytical chemistry Parts-per notation Formaldehyde General Physics and Astronomy Spectral line chemistry.chemical_compound Optics chemistry Optical parametric oscillator Gas detector business Photoacoustic spectroscopy Tunable laser |
Zdroj: | Applied Physics B. 85:285-288 |
ISSN: | 1432-0649 0946-2171 |
DOI: | 10.1007/s00340-006-2295-x |
Popis: | Selective and sensitive detection of formaldehyde (CH2O) was achieved using a grazing-incidence optical parametric oscillator (GIOPO), pumped at high repetition rate, as a light source for photoacoustic spectroscopy. The photoacoustic spectrum of formaldehyde was measured in the range from 2785 to 2840 cm-1 and an absorption line at 2805.0 cm-1 was selected for detection. Concentrations down to 20 ppbv (parts per billion by volume) formaldehyde in nitrogen were recorded. The detection limit determined by background fluctuations was 3 ppbv (S/N=1) for 3 s lock-in time constant and 3 min acquisition time. The 2805.0 cm-1 absorption line of the ν1 vibrational mode was chosen because of the absence of interference with water and carbon-dioxide bands. This allowed the direct detection of formaldehyde in laboratory air without filtering. |
Databáze: | OpenAIRE |
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