Inter-comparisons of VOC oxidation mechanisms based on box model: A focus on OH reactivity
Inter-comparisons of VOC oxidation mechanisms based on box model: A focus on OH reactivity
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基于盒模型的VOC氧化机制的相互比较：关注OH反应性
DOI：
10.1016/j.jes.2021.09.002
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发表时间：
2022
影响因子：
6.9
通讯作者：
Shao Min
中科院分区：
文献类型：
--
作者：
Yang Xiaoyun;Yuan Bin;Peng Zhe;Peng Yuwen;Wu Caihong;Yang Suxia;Li Jin;Shao Min
挥发性有机化合物（VOCs）氧化过程在大气化学中具有重要的作用，其化学反应在化学机理上表现为多种形式。为了更好地理解氧化过程中VOCs的演变，并评估不同机制之间VOCs氧化方案的差异，我们使用总VOC反应性作为诊断和评估工具，以探索六种广泛使用的化学机制的差异。在光化学箱模型中，比较了正戊烷、甲苯、乙烯、异戊二烯和57种光化学评价监测站（PAMS）组分的混合物在高NO_x条件下的总VOC反应性演化。单个前体模拟的总VOC反应性的相互比较显示，所研究的机制之间的氧化方案存在不同程度的差异，这主要归因于有机物质的不同集总方法。PAMS模拟显示出较小的差异比个别前体的情况下，总的VOC反应。SAPRC07和RACM 2的性能被发现更好地匹配MCM的总VOC反应性的模拟。研究表明，模型对次生有机产物、OH浓度和NOx浓度的模拟能力与不同化学机理中OH反应活性的差异有关。本研究中的信息可以用于选择化学机制，以更好地模拟OH在不同环境中的反应性。在这项研究中的结果也提供了方向，以进一步提高建模的能力与化学机制的总VOC反应。
Volatile organic compounds (VOCs) oxidation processes play a very important role in atmospheric chemistry, and the chemical reactions are expressed in various manners in chemical mechanisms. To gain an improved understanding of VOCs evolution during oxidation processes and evaluate the discrepancies of VOCs oxidation schemes among different mechanisms, we used the total VOC reactivity as a diagnostic and evaluated tool to explore the differences for six widely used chemical mechanisms. We compared the total VOC reactivity evolution under high-NO_x conditions for several sets of precursors, including n-pentane, toluene, ethene, isoprene and a mixture of 57 Photochemical Assessment Monitoring Stations (PAMS) species in a 0-D photochemical box model. Inter-comparison of total VOC reactivity of individual precursor simulations showed discrepancies to different extent of the oxidation schemes among the studied mechanisms, which are mainly attributed to the different lumping approaches for organic species. The PAMS simulation showed smaller discrepancy than individual precursor cases in terms of total VOC reactivity. SAPRC07 and RACM2 performances are found to better match the MCM for simulation of total VOC reactivity. Evidences suggest that the performance in simulating secondary organic products, OH concentrations and NO_x concentrations are related to the OH reactivity discrepancies among various chemical mechanisms. Information in this study can be used in selection of chemical mechanisms to better model OH reactivity in different environments. The results in this study also provide directions to further improve the ability in modelling total VOC reactivity with the chemical mechanisms.