Size-segregated aerosols (six stages with a diameter from <0.49 to >7.2 μm) were collected during daytime and nighttime in the summer of 2020 and were analyzed for dicarboxylic acids, isoprene, α/β-pinene and β-caryophyllene secondary organic aerosol (SOA) tracers, aromatic acids, hydroxy-polyacids, monocarboxylic acids and levoglucosan. The vast majority of the detected compounds presented significantly higher (p < 0.05) concentrations in fine than in coarse modes, excluding benzoic and oleic acids for which the higher fine mode than coarse mode concentrations were not significant and pinonic acid which was found at higher coarse mode concentrations. The dominant compound in the fine mode was 2-methylerythritol (mean of 213 ± 79.4 ng m⁻³), whereas in coarse particles palmitic acid was the most abundant (mean of 22.8 ± 9.7 ng m⁻³). All of the detected compounds, except for terephthalic acid, presented higher daytime concentrations, a difference that in the cases of glutaric, suberic, azelaic and pinic acids was significant (p < 0.05). The six-stage size distribution showed various patterns, with most species peaking at particles with a diameter of <1.1 μm suggesting photoxidation sources, while significant peaks at the size of 3–7.2 μm have been observed for suberic, azelaic, pinonic, benzoic, trimellitic and monocarboxylic acids. The hydroscopic growth of particles during nighttime may explain the observed decrease of the fine to coarse concentration ratio. From the employed source apportionment tools four factors where derived explaining 83.0% of total the variance including oxidation of anthropogenic volatile organic compounds (35.6%), oxidation of monoterpenes and sesquiterpenes (21.5%), isoprene's oxidation (14.1%) and photoxidation of unsaturated fatty acids (11.8%).

在2020年夏季的白天和晚上收集按尺寸分类的气溶胶（直径从<0.49到> 7.2μm的六个阶段），并分析二羧酸，异戊二烯，α/β-pine烯和β-石竹烯二次有机气溶胶（SOA）示踪剂，芳族酸，羟基多元酸，一元羧酸和左旋葡聚糖。绝大部分检测到的化合物在精细模式下的浓度均显着高于粗模式（p <0.05），但苯甲酸和油酸的精细模式比粗模式的浓度并不高，而在粗模式下的吡啶酸则较高。模式浓度。精细模式下的主要化合物为2-甲基赤藓糖醇（平均值为213±79.4 ng m ^-3），而在粗颗粒中，棕榈酸含量最高（平均值为22.8±9.7 ng m ^-3）。除对苯二甲酸外，所有检测到的化合物均表现出较高的白天浓度，这一差异与戊二酸，辛二酸，壬二酸和松酸的差异显着（p <0.05）。六级粒度分布显示出各种模式，大多数物种在直径<1.1μm的颗粒处达到峰，表明存在光致氧化源，而在辛二烯，壬二酸，小松子，苯甲酸，偏苯三酸和一元羧酸。夜间吸湿性颗粒的生长可以解释观察到的细到粗浓度比的降低。从所采用的来源分配工具中，可以得出四个因素，占总方差的83.0％，其中包括人为挥发性有机化合物的氧化（35.6％），