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Titel |
OH clock determination by proton transfer reaction mass spectrometry at an environmental chamber |
VerfasserIn |
P. Barmet, J. Dommen, P. F. DeCarlo, T. Tritscher, A. P. Praplan, S. M. Platt, A. S. H. Prévôt, N. M. Donahue, U. Baltensperger |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1867-1381
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Digitales Dokument |
URL |
Erschienen |
In: Atmospheric Measurement Techniques ; 5, no. 3 ; Nr. 5, no. 3 (2012-03-29), S.647-656 |
Datensatznummer |
250002636
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Publikation (Nr.) |
copernicus.org/amt-5-647-2012.pdf |
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Zusammenfassung |
The hydroxyl free radical (OH) is the major oxidizing species in the
lower atmosphere. Measuring the OH concentration is generally difficult and involves
elaborate, expensive, custom-made experimental setups. Thus other more
economical techniques, capable of determining OH concentrations at environmental
chambers, would be valuable. This work is based on
an indirect method of OH concentration measurement, by monitoring an appropriate OH
tracer by proton transfer reaction mass
spectrometry (PTR-MS). 3-pentanol, 3-pentanone and pinonaldehyde (PA) were used
as OH tracers in α-pinene (AP) secondary organic aerosol (SOA) aging studies. In addition we tested
butanol-d9 as a potential "universal" OH tracer and determined its reaction rate constant with
OH: kbutanol-d9 = 3.4(±0.88) × 10−12 cm3 molecule−1 s−1.
In order to make the chamber
studies more comparable among each other as well as to atmospheric
measurements we suggest the use of a chemical (time) dimension: the
OH clock, which corresponds to the integrated OH concentration over
time. |
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