This title appears in the Scientific Report :
2018
Please use the identifier:
http://hdl.handle.net/2128/20058 in citations.
Please use the identifier: http://dx.doi.org/10.5194/acp-18-1611-2018 in citations.
Effects of NO$_{x}$ and SO$_{2}$ on the secondary organic aerosol formation from photooxidation of <i>α</i>-pinene and limonene
Effects of NO$_{x}$ and SO$_{2}$ on the secondary organic aerosol formation from photooxidation of <i>α</i>-pinene and limonene
Anthropogenic emissions such as NOxand SO2influence the biogenic secondary organic aerosol (SOA) for-mation, but detailed mechanisms and effects are still elusive.We studied the effects of NOxand SO2on the SOA for-mation from the photooxidation ofα-pinene and limoneneat ambient relevant...
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Personal Name(s): | Zhao, Defeng (Corresponding author) |
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Schmitt, Sebastian H. / Wang, Mingjin / Acir, Ismail-Hakki / Tillmann, Ralf / Tan, Zhaofeng / Novelli, Anna / Fuchs, Hendrik / Pullinen, Iida / Wegener, Robert / Rohrer, Franz / Wildt, Jürgen / Kiendler-Scharr, Astrid / Wahner, Andreas / Mentel, Thomas F. (Corresponding author) | |
Contributing Institute: |
Troposphäre; IEK-8 |
Published in: | Atmospheric chemistry and physics, 18 (2018) 3, S. 1611 - 1628 |
Imprint: |
Katlenburg-Lindau
EGU
2018
|
DOI: |
10.5194/acp-18-1611-2018 |
Document Type: |
Journal Article |
Research Program: |
Tropospheric trace substances and their transformation processes |
Link: |
Get full text OpenAccess Get full text OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://dx.doi.org/10.5194/acp-18-1611-2018 in citations.
Anthropogenic emissions such as NOxand SO2influence the biogenic secondary organic aerosol (SOA) for-mation, but detailed mechanisms and effects are still elusive.We studied the effects of NOxand SO2on the SOA for-mation from the photooxidation ofα-pinene and limoneneat ambient relevant NOxand SO2concentrations (NOx:< 1to 20 ppb, SO2: < 0.05 to 15 ppb). In these experiments,monoterpene oxidation was dominated by OH oxidation. Wefound that SO2induced nucleation and enhanced SOA massformation. NOxstrongly suppressed not only new particleformation but also SOA mass yield. However, in the presenceof SO2which induced a high number concentration of parti-cles after oxidation to H2SO4, the suppression of the massyield of SOA by NOxwas completely or partly compen-sated for. This indicates that the suppression of SOA yieldby NOxwas largely due to the suppressed new particle for-mation, leading to a lack of particle surface for the organ-ics to condense on and thus a significant influence of vaporwall loss on SOA mass yield. By compensating for the sup-pressing effect on nucleation of NOx, SO2also compensatedfor the suppressing effect on SOA yield. Aerosol mass spec-trometer data show that increasing NOxenhanced nitrate for-mation. The majority of the nitrate was organic nitrate (57–77 %), even in low-NOxconditions (<∼1 ppb). Organic ni-trate contributed 7–26 % of total organics assuming a molec-ular weight of 200 g mol−1. SOA fromα-pinene photooxida-tion at high NOxhad a generally lower hydrogen to carbonratio (H/C), compared to low NOx. The NOxdependenceof the chemical composition can be attributed to the NOxde-pendence of the branching ratio of the RO2loss reactions,leading to a lower fraction of organic hydroperoxides andhigher fractions of organic nitrates at high NOx. While NOxsuppressed new particle formation and SOA mass formation,SO2can compensate for such effects, and the combining ef-fect of SO2and NOxmay have an important influence onSOA formation affected by interactions of biogenic volatileorganic compounds (VOCs) with anthropogenic emissions |