新疆独山子区VOCs组成及其对O3和SOA的贡献

参照美国环保署USEPATO-14标准方法，分别于非采暖、采暖和沙尘期采集新疆独山子区空气样品，用预浓缩仪和气相色谱/质谱联用系统对其挥发性有机物（VOCs）进行分析.结果表明，采样期间独山子区各类VOCs对总VOCs的贡献大小依次是：烷烃（61.80%） > 烯烃（18.62%） > 芳香烃（10.16%） > 乙炔（9.42%）；用气溶胶生成系数（FAC）估算VOCs的二次有机气溶胶（SOA）生成潜势表明，对SOA生成贡献最大的是芳香烃，在非采暖、采暖和沙尘期的贡献率分别为97.80%、87.28%和69.52%；用SPSS软件和广义相加模型（GAM）分析气象因素、VOCs、O₃及NOx之间的关系，表明高温干燥天气有利于O₃生成，且独山子区O₃生成主要受VOCs控制，一些烯烃（如1-丁烯）与O₃呈显著线性关系.

Volatile organic compounds (VOCs) in Dushanzi,Xinjiang: Compositions and contributions to the formation of O3 and SOA

Air samples were collected in the Dushanzi district of Xinjiang Uyghur Autonomous Region, China during the non-heating, heating and sandstorm periods for the analysis of volatile organic compounds (VOCs) by a preconcentrator coupled to a gas chromatography/mass spectrometer according tothe USEPATO-14 standard method. The results showed that group compositions of VOCs in Dushanzi district during the sampling period were ranked in the order ofalkanes (61.80%), alkenes (18.62%), aromatics (10.16%) and acetylene (9.42%). The secondary organic aerosol (SOA) formation potentials of VOCs as estimated by fractional aerosol coefficient (FAC) method revealed that aromatics contributed the most to SOA formation during non-heating, heating and sandstorm period, with contribution percentages of 97.8%, 87.28% and 69.52%, respectively. SPSS software and generalized additive model (GAM) were used to analyze the relationships among meteorological factors, VOCs, O₃ and NO_x. The results demonstrated that high temperature and dry weather were conducive to the formation of O₃. The O₃ formation in Dushanzi district seemed to be VOCs-limited, and alkenes such as 1-butene showed significant linear correlation with O₃.