Liu Sijia, Galeazzo Tommaso, Valorso Richard, Shiraiwa Manabu, Faiola Celia L, Nizkorodov Sergey A
Department of Chemistry, University of California Irvine, Irvine, California 92697, United States.
Univ Paris Est Creteil and Université Paris Cité, CNRS, LISA, Créteil F-94010, France.
Environ Sci Technol. 2024 Jul 17;58(30):13391-401. doi: 10.1021/acs.est.4c04870.
The chemical composition and physical properties of secondary organic aerosol (SOA) generated through OH-initiated oxidation of mixtures containing β-myrcene, an acyclic monoterpene, and d-limonene, a cyclic monoterpene, were investigated to assess the extent of the chemical interactions between their oxidation products. The SOA samples were prepared in an environmental smog chamber, and their composition was analyzed offline using ultraperformance liquid chromatography coupled with electrospray ionization high-resolution mass spectrometry (UPLC-ESI-HRMS). Our results suggested that SOA containing β-myrcene showed a higher proportion of oligomeric compounds with low volatility compared to that of SOA from d-limonene. The formula distribution and signal intensities of the mixed SOA could be accurately predicted by a linear combination of the mass spectra of the SOA from individual precursors. Effects of cross-reactions were observed in the distribution of isomeric oxidation products within the mixed SOA, as made evident by chromatographic analysis. On the whole, β-myrcene and d-limonene appear to undergo oxidation by OH largely independently from each other, with only subtle effects from cross-reactions influencing the yields of specific oxidation products.
通过羟基引发含有无环单萜β-月桂烯和环状单萜d-柠檬烯的混合物氧化生成的二次有机气溶胶（SOA）的化学成分和物理性质进行了研究，以评估其氧化产物之间化学相互作用的程度。在环境烟雾箱中制备了SOA样品，并使用超高效液相色谱与电喷雾电离高分辨率质谱联用（UPLC-ESI-HRMS）对其成分进行离线分析。我们的结果表明，与来自d-柠檬烯的SOA相比，含有β-月桂烯的SOA显示出更高比例的低挥发性低聚物化合物。混合SOA的分子式分布和信号强度可以通过各个前体的SOA质谱的线性组合准确预测。色谱分析表明，在混合SOA中异构氧化产物的分布中观察到了交叉反应的影响。总体而言，β-月桂烯和d-柠檬烯似乎在很大程度上彼此独立地被羟基氧化，只有交叉反应的细微影响会影响特定氧化产物的产率。
