Single particle diversity and mixing state of carbonaceous aerosols in Guangzhou, China
| Autor: | Mei Li, Chak K. Chan, Dui Wu, Zhengxu Huang, Suxia Yang, Cheng Wu, Masao Gen, Zhong Fu, Zhen Zhou, Wei Gao, Peng Cheng, Feng Hao, Berto Paul Yok Long Lee, Lei Li, Chunlei Cheng |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Total organic carbon
Environmental Engineering 010504 meteorology & atmospheric sciences Mixing (process engineering) chemistry.chemical_element 010501 environmental sciences 01 natural sciences Pollution Nitrogen Aerosol chemistry.chemical_compound Nitrate chemistry Environmental chemistry Environmental Chemistry Particle Absorption (chemistry) Waste Management and Disposal Chemical composition 0105 earth and related environmental sciences |
| Zdroj: | Science of The Total Environment. 754:142182 |
| ISSN: | 0048-9697 |
| DOI: | 10.1016/j.scitotenv.2020.142182 |
| Popis: | Many field studies have investigated the formation mechanisms of organic aerosol (OA) based on bulk analysis, yet the source and formation process of individual organic particles may be quite different due to the diversity of chemical composition and mixing state in single particles. Here we present the observation results of chemical composition and mixing state of carbonaceous single particles at an urban site in Guangzhou. The carbonaceous particles accounted for 74.6% of the total detected single particles, and were grouped into four types including elemental carbon-aged (EC-aged), elemental and organic carbon (ECOC), organic carbon-rich (OC-rich) and secondary ions-rich (SEC) particles. The formation of EC-aged particles was closely associated with the absorption of organics onto fresh EC particles from primary sources, and the further enrichment of organics in EC-aged particles resulted in the production of ECOC particles. In the daytime OC-rich and SEC particles were mainly produced from the photochemical reactions, while in the nighttime their sharp increases were found along with the enrichment of nitrate and organic nitrogen fragments, suggesting the heterogeneous formation of nitrate and organic nitrogen in OC-rich and SEC particles. The production rates of carbonaceous particles were also investigated in an episodic event, and the EC-aged particles showed the highest production rate compared to the other carbonaceous particles both in the daytime and nighttime, suggesting a significant role of EC in the formation and aging process of carbonaceous particles. The results from this work have revealed different formation processes and production rates of carbonaceous particles due to their diversity in mixing state, providing further insights into the formation mechanisms of OA in field studies. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect