 |
| Titel |
Functional group composition of ambient and source organic aerosols determined by tandem mass spectrometry |
| VerfasserIn |
J. Dron, I. Haddad, B. Temime-Roussel, J.-L. Jaffrezo, H. Wortham, N. Marchand |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 10, no. 15 ; Nr. 10, no. 15 (2010-08-03), S.7041-7055 |
| Datensatznummer |
250008669
|
| Publikation (Nr.) |
 copernicus.org/acp-10-7041-2010.pdf |
|
|
|
|
|
| Zusammenfassung |
| The functional group composition of various organic aerosols (OA) is
investigated using a recently developed analytical approach based on
atmospheric pressure chemical ionisation-tandem mass spectrometry
(APCI-MS/MS). The determinations of three functional groups contents are
performed quantitatively by neutral loss (carboxylic and carbonyl groups,
R-COOH and R-CO-R´ respectively) and precursor ion (nitro groups,
R-NO2) scanning modes of a tandem mass spectrometer. Major organic
aerosol sources are studied: vehicular emission and wood combustion for
primary aerosol sources; and a secondary organic aerosol (SOA) produced
through photooxidation of o-xylene. The results reveal significant differences
in the functional group contents of these source aerosols. The laboratory
generated SOA is dominated by carbonyls while carboxylics are preponderate
in the wood combustion particles. On the other hand, vehicular emissions are
characterised by a strong nitro content. The total amount of the three
functional groups accounts for 1.7% (vehicular) to 13.5% (o-xylene
photooxidation) of the organic carbon. Diagnostic functional group ratios
are then used to tentatively discriminate sources of particles collected in
an urban background environment located in an Alpine valley (Chamonix,
France) during a strong winter pollution event. The three functional groups
under study account for a total functionalisation rate of 2.2 to 3.8% of
the organic carbon in this ambient aerosol, which is also dominated by
carboxylic moieties. In this particular case study of a deep alpine valley
during winter, we show that the nitro- and carbonyl-to-carboxylic diagnostic
ratios can be a useful tool to discriminate sources. In these conditions,
the total OA concentrations are highly dominated by wood combustion OA. This
result is confirmed by an organic markers source apportionment approach
which assess a wood burning organic carbon contribution of about 60%.
Finally, examples of functional group mass spectra of all aerosols under
study are presented, and additional perspectives offered by the mass spectra
in terms of OA characterisation are discussed. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|