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| Titel |
Characterization and source apportionment of submicron aerosol with aerosol mass spectrometer during the PRIDE-PRD 2006 campaign |
| VerfasserIn |
R. Xiao, N. Takegawa, M. Zheng, Y. Kondo, Y. Miyazaki, T. Miyakawa, M. Hu, M. Shao, L. Zeng, Y. Gong, K. Lu, Z. Deng, Y. Zhao, Y. H. Zhang |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1680-7316
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 11, no. 14 ; Nr. 11, no. 14 (2011-07-18), S.6911-6929 |
| Datensatznummer |
250009923
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| Publikation (Nr.) |
 copernicus.org/acp-11-6911-2011.pdf |
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| Zusammenfassung |
| Size-resolved chemical compositions of non-refractory submicron aerosol were
measured using an Aerodyne quadrupole aerosol mass spectrometer (Q-AMS) at
the rural site Back Garden (BG), located ~50 km northwest of Guangzhou
in July 2006. This paper characterized the submicron aerosol particles of
regional air pollution in Pearl River Delta (PRD) in the southern China.
Organics and sulfate dominated the submicron aerosol compositions, with
average mass concentrations of 11.8 ± 8.4 μg m−3 and 13.5 ± 8.7 μg m−3,
respectively. Unlike other air masses, the air
masses originated from Southeast-South and passing through the PRD urban
areas exhibited distinct bimodal size distribution characteristics for both
organics and sulfate: the first mode peaked at vacuum aerodynamic diameters
(Dva) ∼200 nm and the second mode occurred at Dva from
300–700 nm. With the information from AMS, it was found from this study that
the first mode of organics in PRD regional air masses was contributed by
both secondary organic aerosol formation and combustion-related emissions,
which is different from most findings in other urban areas (first mode of
organics primarily from combustion-related emissions). The analysis of AMS
mass spectra data by positive matrix factorization (PMF) model identified
three sources of submicron organic aerosol including hydrocarbon-like
organic aerosol (HOA), low volatility oxygenated organic aerosol (LV-OOA)
and semi-volatile oxygenated organic aerosol (SV-OOA). The strong
correlation between HOA and EC indicated primary combustion emissions as the
major source of HOA while a close correlation between SV-OOA and
semi-volatile secondary species nitrate as well as between LV-OOA and
nonvolatile secondary species sulfate suggested secondary aerosol formation
as the major source of SV-OOA and LV-OOA at the BG site. However, LV-OOA was
more aged than SV-OOA as its spectra was highly correlated with the
reference spectra of fulvic acid, an indicator of aged and oxygenated
aerosol. The origin of HOA and OOA (the sum of LV-OOA and SV-OOA) has been
further confirmed by the statistics that primary organic carbon (POC) and
secondary organic carbon (SOC), estimated by the EC tracer method, were
closely correlated with HOA and OOA, respectively. The results of the EC
tracer method and of the PMF model revealed that primary organic aerosol
(POA) constituted ~34–47 % of OA mass and secondary organic aerosol
(SOA) constituted ~53–66 % of regional organic aerosol in PRD
during summer season. The presence of abundant SOA was consistent with water
soluble organic carbon (WSOC) results (accounting for ~60 % of OC on
average) by Miyazaki et al. (2009) for the same campaign. OOA correlated
well with WSOC at the BG site, indicating that most OOA were water soluble.
More specifically, approximately 86 % of LV-OOA and 61 % of SV-OOA were
estimated as water soluble species on the basis of carbon content
comparison. |
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