Direct detection of acetylene in air by continuous wave cavity ring-down spectroscopy
2010 (English)In: Applied physics. B, Lasers and optics (Print), ISSN 0946-2171, E-ISSN 1432-0649, Vol. 101, no 3, 671-682 p.Article in journal (Refereed) Published
Diode laser-based continuous wave cavity ring-down spectroscopy (cw-CRDS) in the near-infrared region has been used to measure the mixing ratio of acetylene (C(2)H(2)) in ambient air. Detection limits of 120 parts per trillion by volume (pptv) for 20 min and 340 pptv for 70 s acquisition time were achieved without sample pre-concentration, measuring on a C(2)H(2) absorption line at 6565.620 cm(-1) (similar to 1523 nm). Several indoor and outdoor air samples were collected at different locations in the Helsinki metropolitan area and analyzed using static-cell measurements. In addition, flow measurements of indoor and outdoor air have been performed continuously over several days with a time resolution of down to one minute. Baseline acetylene levels in the range of 0.4 to 3 parts per billion by volume (ppbv), with a maximum around midday and a minimum during the night, were measured. Sudden high mixing ratios of up to 60 ppbv were observed in outdoor air during daytime on a minute time scale. In general, the indoor mixing ratios were found to be higher than those in outdoor air. The acetylene levels correlated with the ambient CO levels and with outdoor temperature.
Place, publisher, year, edition, pages
2010. Vol. 101, no 3, 671-682 p.
volatile organic-compounds, near-infrared region, sample preconcentration, output spectroscopy, ambient air, nice-ohms, c2h2, voc, spectrometry, sensitivity
Atom and Molecular Physics and Optics Environmental Sciences Meteorology and Atmospheric Sciences
IdentifiersURN: urn:nbn:se:umu:diva-64491DOI: 10.1007/s00340-010-4027-5ISI: 000284110800026OAI: oai:DiVA.org:umu-64491DiVA: diva2:601746
678VQ Times Cited:4 Cited References Count:362013-01-302013-01-302015-03-12Bibliographically approved