Global S&T Development Trend Analysis Platform of Resources and Environment
DOI | 10.5194/acp-18-14539-2018 |
Heterogeneous OH oxidation of secondary brown carbon aerosol | |
Schnitzler, Elijah G.; Abbatt, Jonathan P. D. | |
2018-10-11 | |
发表期刊 | ATMOSPHERIC CHEMISTRY AND PHYSICS
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ISSN | 1680-7316 |
EISSN | 1680-7324 |
出版年 | 2018 |
卷号 | 18期号:19页码:14539-14553 |
文章类型 | Article |
语种 | 英语 |
国家 | Canada |
英文摘要 | Light-absorbing organic aerosol, or brown carbon (BrC), has significant but poorly constrained effects on climate; for example, oxidation in the atmosphere may alter its optical properties, leading to absorption enhancement or bleaching. Here, we investigate for the first time the effects of heterogeneous OH oxidation on the optical properties of a laboratory surrogate of aqueous, secondary BrC in a series of photo-oxidation chamber experiments. The BrC surrogate was generated from aqueous resorcinol, or 1,3-dihydroxybenzene, and H2O2 exposed to > 300 nm radiation that is atomized, passed through trace gas denuders, and injected into the chamber, which was conditioned to either 15 % or 60 % relative humidity (RH). Aerosol absorption and scattering coefficients and single scattering albedo (SSA) at 405 nm were measured using a photoacoustic spectrometer. At 60 % RH, upon OH exposure, absorption first increased, and the SSA decreased sharply. Subsequently, absorption decreased faster than scattering, and SSA increased gradually. Comparisons to the modelled trend in SSA, based on Mie theory calculations, confirm that the observed trend is due to chemical evolution, rather than slight changes in particle size. The initial absorption enhancement is likely due to molecular functionalization and/or oligomerization and the bleaching to fragmentation. By contrast, at 15 % RH, slow absorption enhancement was observed without appreciable bleaching. A multi-layer kinetics model, consisting of two surface reactions in series, was constructed to provide further insights regarding the RH dependence of the optical evolution. Candidate parameters suggest that the oxidation is efficient, with uptake coefficients on the order of unity. The parameters also suggest that, as RH decreases, reactivity decreases and aerosol viscosity increases, such that particles are well-mixed at 60 % RH but not at 15 % RH. These results further the current understanding of the complex processing of BrC that may occur in the atmosphere. |
领域 | 地球科学 |
收录类别 | SCI-E |
WOS记录号 | WOS:000447008300001 |
WOS关键词 | GAS-PARTICLE INTERACTIONS ; BIOMASS BURNING PARTICLES ; CHARGE-TRANSFER COMPLEXES ; KINETIC-MODEL FRAMEWORK ; CLOUD SURFACE-CHEMISTRY ; AQUEOUS-PHASE REACTIONS ; AIR-WATER-INTERFACE ; DOUBLE-LAYER MODEL ; LIGHT-ABSORPTION ; ORGANIC AEROSOL |
WOS类目 | Environmental Sciences ; Meteorology & Atmospheric Sciences |
WOS研究方向 | Environmental Sciences & Ecology ; Meteorology & Atmospheric Sciences |
引用统计 | |
文献类型 | 期刊论文 |
条目标识符 | http://119.78.100.173/C666/handle/2XK7JSWQ/30672 |
专题 | 地球科学 |
作者单位 | Univ Toronto, Dept Chem, Toronto, ON M5S 3H6, Canada |
推荐引用方式 GB/T 7714 | Schnitzler, Elijah G.,Abbatt, Jonathan P. D.. Heterogeneous OH oxidation of secondary brown carbon aerosol[J]. ATMOSPHERIC CHEMISTRY AND PHYSICS,2018,18(19):14539-14553. |
APA | Schnitzler, Elijah G.,&Abbatt, Jonathan P. D..(2018).Heterogeneous OH oxidation of secondary brown carbon aerosol.ATMOSPHERIC CHEMISTRY AND PHYSICS,18(19),14539-14553. |
MLA | Schnitzler, Elijah G.,et al."Heterogeneous OH oxidation of secondary brown carbon aerosol".ATMOSPHERIC CHEMISTRY AND PHYSICS 18.19(2018):14539-14553. |
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