Measurements of the Diversity of Shape and Mixing State for Ambient Black Carbon Particles
Measurements of the Diversity of Shape and Mixing State for Ambient Black Carbon Particles
复制标题
常温黑碳颗粒形状和混合状态多样性的测量
DOI：
10.1029/2021gl094522
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发表时间：
2021-09-16
影响因子：
5.2
通讯作者：
Wu, Yu
中科院分区：
文献类型：
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作者：
Hu, Kang;Liu, Dantong;Wu, Yu
炭黑(BC)复杂的颗粒形态给其光学性质的限制带来了很大的不确定性。特别是，由于缺乏直接的环境量化，BC芯和涂层如何结合的多样性尚未得到解决。在本研究中，通过同时测量电迁移率直径(Dm)和光学体积当量直径(Dve)，首次量化了环境中含BC粒子在不同混合状态下的动态形状因子(χ=Dm/Dve)。北京市区BC的χ分布广泛，为1.4±0.43。具有较大耐火核心的颗粒表现出较高的非球形性和较高的χ。涂层与红细胞的体积比(VR)增加10倍，可使分形BC的比例降低36%。本研究提出了一种描述粒子形状的χ-VR空间，该空间能够将所有环境量化的BC形态都包含在光学模型中。
The complex particle morphology of black carbon (BC) induces considerable uncertainties in constraining its optical properties. In particular, the diversity of how the BC core and coating are combined is yet to be resolved due to the lack of direct ambient quantification. In this study, by concurrent measurements of the electrical mobility diameter (Dm) and optical volume‐equivalent diameter (Dve), the dynamic shape factor (χ = Dm/Dve) of ambient BC‐containing particles at different mixing states was quantified for the first time. BC in urban Beijing showed a widely distributed χ of 1.4 ± 0.43. Particles with larger refractory BC (rBC) cores showed higher non‐sphericity and higher χ. A ten‐fold increase in the volume ratio of the coating over rBC (VR) could decrease the fraction of fractal BC by 36%. This study proposed a χ‐VR space to describe the particle shape, which is able to include all ambient quantified BC morphologies in optical model.