Enhanced mixing state of black carbon with nitrate in single particles during haze periods in Zhengzhou, China  

作　　者：Qianni Zhou Chunlei Cheng Suxia Yang Minghao Yuan Jingjing Meng Haifeng Gong Qien Zhong Yao Zhang Yutong Xie Zhen Zhou Mei Li 

机构地区：[1]Institute of Mass Spectrometry and Atmospheric Environment,Guangdong Provincial Engineering Research Center for On-line Source Apportionment System of Air Pollution,Jinan University,Guangzhou 510632,China [2]Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality,Guangzhou 510632,China [3]School of Environment and Planning,Liaocheng University,Liaocheng 252000,China [4]Institute for Environment and Climate Research,Jinan University,Guangzhou 510632,China [5]Zhengzhou Environmental Protection Monitoring Center Station,Zhengzhou 450007,China

出　　处：《Journal of Environmental Sciences》2022年第1期185-196,共12页环境科学学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(No.41827804,41805093);the Guangzhou Economic and Technological Development District International Science and Technology Cooperation Project(No.2018GH08);the International Science and Technology Cooperation Project of Guangdong Province(No.2018A050506020);the Pearl River Nova Program of Guangzhou(No.201806010064)。

摘　　要：Black carbon(BC)plays an important role in air quality and climate change,which is closely associated with its mixing state and chemical compositions.In this work the mixing state of BC-containing single particles was investigated to explore the evolution process of ambient BC particles using a single particle aerosol mass spectrometer(SPAMS)in March 2018 in Zhengzhou,China.The BC-containing particles accounted for 61.4%of total detected ambient single particles and were classified into five types including BC-nitrate(BC-N,52.3%)as the most abundant species,followed by BC-nitrate-sulfate(BC-NS,22.4%),BCOC(16.8%),BC-fresh(BC-F,4.5%)and BC-sulfate particles(BC-S,4.0%).With enhancement of the ambient nitrate concentration,the relative peak area(RPA)of nitrate in BC-N and BC–NS particles both increased,yet only the number fraction(N_(f))of BC–N particles increased while the N_(f) of BC-NS particles decreased,suggesting that the enhanced mixing state of BC with nitrate was mainly due to the increase in the ambient nitrate mass concentration.In addition,the Nfof BC-N decreased from 65.3%to 28.4%as the absorbing Angstrom exponents(AAE)of e BC increased from 0.75 to 1.45,which indicated the reduction of light absorption ability of aged BC particles with the enhanced formation of BC-N particles.The results of this work indicated a change in the mixing state of BC particles due to the dominance of nitrate in PM_(2.5),which also influenced the optical properties of aged BC particles.

关 键 词：Single particle Black carbon Mixing state NITRATE Aging process 

分 类 号：X513[环境科学与工程—环境工程]