| Autor: |
Müller, L., Reinnig, M.-C., Naumann, K. H., Saathoff, H., Mentel, T. F., Donahue, N. M., Hoffmann, T., Keutsch, F. |
| Předmět: |
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| Zdroj: |
Atmospheric Chemistry & Physics; 2012, Vol. 12 Issue 3, p1483-1496, 17p, 3 Diagrams, 4 Charts, 4 Graphs |
| Abstrakt: |
This paper presents the results of mass spectrometric investigations of the OH-initiated oxidative aging of α-pinene SOA under simulated tropospheric conditions at the large aerosol chamber facility AIDA, Karlsruhe Institute of Technology. In particular, the OH-initiated oxidation of pure pinic and pinonic acid, two well-known oxidation products of α-pinene, was investigated. Two complementary analytical techniques were used, on-line atmospheric pressure chemical ionization/mass spectrometry (APCI/MS) and filter sampling followed by liquid chromatography/mass spectrometry (LC/ESI-MS). The results show that 3-methyl-1,2,3-butanetricarboxylic acid (MBTCA), a very low volatile α-pinene SOA product and a tracer compound for terpene SOA, is formed from the oxidation of pinonic acid and that this oxidation takes place in the gas phase. This finding is confirmed by temperature-dependent aging experiments on whole SOA formed from α-pinene, in which the yield of MBTCA scales with the pinonic acid fraction in the gas phase. Based on the results, several feasible gas-phase radical mechanisms are discussed to explain the formation of MBTCA from OH-initiated pinonic acid oxidation. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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