Institute for the Dynamics of Environmental Processes CNR, Via Torino 155, 30172 Venice-Mestre, Italy.
Department of Environmental Sciences, Informatics and Statistics, Ca' Foscari University of Venice, Via Torino 155, 30172 Venice-Mestre, Italy.
Sci Total Environ. 2019 Mar 25;658:1423-1439. doi: 10.1016/j.scitotenv.2018.12.298. Epub 2018 Dec 21.
Water soluble organic carbon significantly contributes to aerosol's carbon mass and its chemical composition is poorly characterized due to the huge number of species. In this study, we determined 94 water-soluble compounds: inorganic ions (Cl, Br, I, NO, SO,K, Mg, Na, NH, Ca), organic acids (methanesulfonic acid and C-C carboxylic acids), monosaccharides, alcohol-sugars, levoglucosan and its isomers, sucrose, phenolic compounds, free l- and d-amino acids and photo-oxidation products of α-pinene (cis-pinonic acid and pinic acid). The sampling was conducted using a micro-orifice uniform deposit impactor (MOUDI) at the urban area of Mestre-Venice from March to May 2016. The main aim of this work is to identify the source of each detected compound, evaluating its particle size distribution. Clear differences in size distributions were observed for each class of analyzed compounds. The positive matrix factorization (PMF) model was used to identify six factors related to different sources: a) primary biogenic aerosol particles with particle size > 10 μm; b) secondary sulfate contribution; c) biomass burning; d) primary biogenic aerosol particles distributed between 10 and 1 μm; e) an aged sea salt input and f) SOA pinene. Each factor was also characterized by different composition in waters soluble compounds and different particles size distribution.
水溶性有机碳对气溶胶的碳质量有很大贡献，由于物种数量众多，其化学组成的特征描述很差。在这项研究中，我们测定了 94 种水溶性化合物：无机离子（Cl、Br、I、NO、SO、K、Mg、Na、NH、Ca）、有机酸（甲烷磺酸和 C-C 羧酸）、单糖、醇糖、左旋葡聚糖及其异构体、蔗糖、酚类化合物、游离 l-和 d-氨基酸以及α-蒎烯的光氧化产物（顺式-松脂酸和松脂酸）。采样是在 2016 年 3 月至 5 月在威尼斯的梅斯特市城区使用微孔均匀沉积撞击器（MOUDI）进行的。这项工作的主要目的是确定每个检测到的化合物的来源，评估其颗粒尺寸分布。分析的化合物每类的粒径分布都有明显差异。采用正定矩阵因子（PMF）模型来识别与不同来源相关的六个因素：a）粒径大于 10μm的主要生物源气溶胶颗粒；b）二次硫酸盐贡献；c）生物质燃烧；d）粒径在 10 和 1μm 之间的主要生物源气溶胶颗粒；e）老化的海盐输入和 f）松烯 SOA。每个因素还具有不同的水溶性化合物组成和不同的颗粒尺寸分布特征。
