本研究以秦岭北麓地区为研究对象，通过梯度高度采样（0-300m）结合单颗粒气溶胶采样技术，揭示了冬季夜间秦岭北麓地区黑碳（BC）的化学组成、混合态演变及其气象驱动的垂直分布规律。结果显示，不同高度采集的BC整体组成相似：表现出明显的³⁹K⁺、²³Na⁺、Cn^±、OC、硝酸盐（⁶²NO_3­­­⁻）、硫酸盐（⁹⁷HSO₄⁻）、²⁶CN⁻和⁴²CNO⁻信号，其中有87-91%的黑碳与硝酸盐发生混合。利用ART-2a对黑碳进行分类，包括EC-dominant、EC-CN、EC-N、EC-S、EC-NS、EC-OC、EC-alkali、EC-metal和EC-other八种类别。EC-N和EC-alkali颗粒占有较高的比例，且EC-N在100m高度处的相对贡献最大。分析每种类型的黑碳与二次物种的混合态显示，EC-CN颗粒与左旋葡聚糖发生了明显混合，表明这部分颗粒可能来源于生物质燃烧(Bi et al., 2011; Bond et al., 2013)。与EC-dominant颗粒相比，而EC-N、EC-NS、EC-S、EC-OC、EC-alkali和EC-metal颗粒与硫酸盐和硝酸盐的混合程度明显增加，表明经历了大气老化过程。此外，研究了结合夜间低温、高湿特征，阐明气象条件对硝酸盐形成的影响(Jeon et al., 2024; Jiang et al., 2024; Shen et al., 2020; Yun et al., 2018)，为山地夜间污染物滞留机制研究提供新视角。

References：
Bi, X., Zhang, G., Li, L., Wang, X., Li, M., Sheng, G., . . . Zhou, Z. (2011). Mixing state of biomass burning particles by single particle aerosol mass spectrometer in the urban area of PRD, China. Atmospheric Environment, 45(20), 3447-3453. doi:https://doi.org/10.1016/j.atmosenv.2011.03.034
Bond, T. C., Doherty, S. J., Fahey, D. W., Forster, P. M., Berntsen, T., DeAngelo, B. J., . . . Zender, C. S. (2013). Bounding the role of black carbon in the climate system: A scientific assessment. Journal of Geophysical Research: Atmospheres, 118(11), 5380-5552. doi:https://doi.org/10.1002/jgrd.50171
Jeon, J. W., Park, S. W., Han, Y. J., Lee, T., Lee, S. H., Park, J. M., . . . Hopke, P. K. (2024). Nitrate formation mechanisms causing high concentration of PM(2.5) in a residential city with low anthropogenic emissions during cold season. Environ Pollut, 352, 124141. doi:10.1016/j.envpol.2024.124141
Jiang, S., Wang, Y., Huang, X., Liu, B., Nie, D., Ge, Y., . . . Ye, J. (2024). Characteristics of Nocturnal Boundary Layer over a Subtropical Forest: Implications for the Dispersion and Fate of Atmospheric Species. Environmental Science & Technology, 58(52), 23075-23087. doi:10.1021/acs.est.4c05051
Shen, J., Zhao, Q., Cheng, Z., Wang, P., Ying, Q., Liu, J., . . . Fu, Q. (2020). Insights into source origins and formation mechanisms of nitrate during winter haze episodes in the Yangtze River Delta. Sci Total Environ, 741, 140187. doi:10.1016/j.scitotenv.2020.140187
Yun, H., Wang, W., Wang, T., Xia, M., Yu, C., Wang, Z., . . . Zhou, Y. (2018). Nitrate formation from heterogeneous uptake of dinitrogen pentoxide during a severe winter haze in southern China. Atmospheric Chemistry and Physics, 18(23), 17515-17527. doi:10.5194/acp-18-17515-2018
 

黑碳气溶胶,质谱,混合态,老化过程