Observational Evidence for the Involvement of Dicarboxylic Acids in Particle Nucleation

• DOI: 10.1021/acs.estlett.0c00270
• Publication Date: 2020-05-19T15:13:16Z
• Authors: Xin Fang; Min Hu; Dongjie Shang; Rongzhi Tang; Linlin Shi; Tinja Olenius; Yujue Wang; Hui Wang; Zijing Zhang; Shiyi Chen; Xuena Yu; Wenfei Zhu; Shengrong Lou; Yan Ma; Xin Li; Limin Zeng; Zhijun Wu; Jun Zheng; Song Guo
• Keywords: Succinic acid; Dimethylamine; Particle (ecology); Dicarboxylic acid

Gaseous dicarboxylic acids (diacids) are suggested to participate in atmospheric new particle formation via bonding with sulfuric acid (SA), ammonia (NH3), amines, and other molecules. However, there is a lack of observational evidence for the involvement diacids nucleation. Comprehensive measurements were conducted at rural site North China Plain winter, unexpectedly high nucleation rates (JOBS, 30.5–839.7 cm–3 s–1) observed under low SA levels (0.7 × 106 4.4 cm–3). Neither SA-NH3 nor SA-dimethylamine (DMA) mechanisms could fully explain JOBS. diacid monomers dimers diacid-SA-DMA clusters identified this study. The JOBS values enhanced by factor 5 10 as signal intensities increased 4-fold. Products signals concentrations showed positive correlation (Pearson's coefficient = 0.72). Experimental was found that succinic competes second molecule addition SA·DMA cluster. estimated be 1–3 orders magnitude higher than those SA. We propose actively may dominate initial steps [diacids]/[SA] ratios.