As emission standards tighten, addressing Volatile Organic Compounds (VOCs) has become more urgent. The VOC emissions from diesel vehicles are underestimated in transportation, emphasizing the need to reexamine their emission characteristics. Our study analyzed four diesel vehicles and found that aromatics and alkanes were the dominant categories of VOCs, which accounted for approximately 24 % and 19 %, respectively. Tetrahydrofuran, acetone, and toluene were identified as the main components of VOCs, accounting for 78 % of the total emissions. Specifically, the implementation of tighter emission standards for diesel vehicles resulted in a reduction in the contribution of alkanes to VOC emissions, while that of aromatics increased notably. As the driving speed increased, emissions of aromatics and Volatile Halogenated Hydrocarbons (VHCs) experienced a decreasing trend. In addition, Selective Catalytic Reduction (SCR) has the significant impact on aromatics and VHCs, while cold and hot starts phases affect aromatic emissions mostly, as confirmed by Criteria Importance Through Intercriteria Correlation (CRITIC) analysis.

中文翻译：

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柴油车排放：剖析对 VOC 成分浓度变化的多因素影响


随着排放标准的收紧，解决挥发性有机化合物 （VOC） 问题变得更加紧迫。柴油车的 VOC 排放在运输过程中被低估，强调需要重新检查其排放特性。我们的研究分析了四辆柴油车，发现芳烃和烷烃是 VOC 的主要类别，分别约占 24% 和 19%。四氢呋喃、丙酮和甲苯被确定为 VOC 的主要成分，占总排放量的 78%。具体来说，对柴油车实施更严格的排放标准导致烷烃对 VOC 排放的贡献减少，而芳烃的贡献显着增加。随着行驶速度的增加，芳烃和挥发性卤代烃 （VHC） 的排放呈下降趋势。此外，选择性催化还原 （SCR） 对芳烃和 VHC 有显著影响，而冷和热启动阶段对芳烃排放的影响最大，这通过标准间相关性的标准重要性 （CRITIC） 分析证实了这一点。