期刊
ENVIRONMENTAL SCIENCE & TECHNOLOGY
卷 55, 期 9, 页码 5677-5688出版社
AMER CHEMICAL SOC
DOI: 10.1021/acs.est.0c07569
关键词
biomass burning; optical properties; smoldering and flaming; black carbon; organic aerosol; aerosol aging
资金
- National Key Research and Development Program of China [2016YFA0602001, 2016YFA0602002]
- National Natural Science Foundation of China [41875167]
- Department of Earth and Environmental Science in the University of Manchester
This study evaluated the detailed mixing state between BC and OA, and performed optical modeling to achieve a closure of aerosol-absorbing properties. OA under flaming conditions exhibited higher absorptivity than under smoldering conditions.
Emissions of light-absorbing black carbon (BC) and organic aerosol (OA) from biomass burning are presented as complex mixtures, which introduce challenges in modeling their absorbing properties. In this study, we chose typical residential wood burning emission and used a novel designed chamber to investigate the early stage evolution of plumes from different burning phases under real ambient conditions. The detailed mixing state between BC and OA was evaluated, on the basis of which optical modeling was performed to achieve a closure of aerosol-absorbing properties. Intensive secondary OA (SOA) formation was observed under solar radiation. OA from flaming conditions showed a higher absorptivity than from smoldering conditions, as OA is mostly internally and externally mixed with BC, respectively. For flaming (smoldering), the imaginary refractive index of OA (k(OA)) was initially at 0.03 +/- 0.01 (0.001) and 0.15 +/- 0.02 (0.05 +/- 0.02) at lambda = 781 and 405 nm, respectively, with a half-decay time of 2-3 h in light but a <40% decrease under dark within 5 h. The production of less-absorbing SOA in the first 1-2 h and possible subsequent photobleaching of chromophores contributed to the decrease of k(OA). The enhanced abundance but decreased absorptivity of coatings on BC resulted in a relatively maintainable absorptivity of BC-containing particles during evolution.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据