Effects of photochemical oxidation on the mixing state and light absorption of black carbon in the urban atmosphere of China
Effects of photochemical oxidation on the mixing state and light absorption of black carbon in the urban atmosphere of China
复制标题
光化学氧化对我国城市大气中黑碳混合状态和光吸收的影响
DOI：
10.1088/1748-9326/aa64ea
复制
发表时间：
2017
影响因子：
6.7
通讯作者：
Prevot Andre S. H.
中科院分区：
文献类型：
--
作者：
Wang Qiyuan;Huang Rujin;Zhao Zhuzi;Cao Junji;Ni Haiyan;Tie Xuexi;Zhu Chongshu;Shen Zhenxing;Wang Meng;Dai Wenting;Han Yongming;Zhang Ningning;Prevot Andre S. H.
研究了中国两个大城市难降解炭黑（rBC）气溶胶混合状态与大气氧化能力的关系，以评估氧化剂对颗粒物光吸收效应的可能影响。厚涂层的rBC颗粒（F rBC）的数量分数与氧化剂浓度（OX= O3 + NO2）的测量呈正相关，表明在更多的氧化条件下涂层rBC颗粒的增强。北京和西安的F rBC与OX的线性回归斜率分别为0.58%ppb − 1和0.84%ppb − 1，这些关系为研究rBC混合状态与大气氧化过程的关系提供了一些见解。在西安白天，rBC的质量吸收截面（MAC rBC）随着OX的增加而增加，增加率为0.26 m2 g− 1 ppb− 1，这表明更多的氧化条件导致内部混合，从而增强了rBC颗粒的光吸收能力。了解F rBC和MAC rBC的增长率作为OX的函数的依赖性可能会导致处理变暖效应的气候模型的改进，但需要在不同的城市和季节进行更多的研究来衡量这些发现的更广泛的影响。
The relationship between the refractory black carbon (rBC) aerosol mixing state and the atmospheric oxidation capacity was investigated to assess the possible influence of oxidants on the particles' light absorption effects at two large cities in China. The number fraction of thickly-coated rBC particles (F rBC) was positively correlated with a measure of the oxidant concentrations (OX= O 3+ NO 2), indicating an enhancement of coated rBC particles under more oxidizing conditions. The slope of a linear regression of F rBC versus OX was 0.58% ppb− 1 for Beijing and 0.84% ppb− 1 for Xi'an, and these relationships provide some insights into the evolution of rBC mixing state in relation to atmospheric oxidation processes. The mass absorption cross-section of rBC (MAC rBC) increased with OX during the daytime at Xi'an, at a rate of 0.26 m 2 g− 1 ppb− 1, suggesting that more oxidizing conditions lead to internal mixing that enhances the light-absorbing capacity of rBC particles. Understanding the dependence of the increasing rates of F rBC and MAC rBC as a function of OX may lead to improvements of climate models that deal with the warming effects, but more studies in different cities and seasons are needed to gauge the broader implications of these findings.