基于聚类分析的长治市夏季VOCs来源及活性

分析长治市夏季环境VOCs浓度及其反应活性（以OH·消耗速率计），基于聚类分析与正定矩阵因子分解法 （PMF）解析VOCs来源.结果表明：长治市总VOCs平均浓度为37.40 μg/m³，平均活性水平为5.07s^-1，具有本地新鲜排放和反应后混合的特征.机动车排放、燃煤、液化石油气/天然气（LPG/ NG）使用、工艺过程和溶剂使用源对环境VOCs的贡献分别为29.7%、29.2%、23.5%、11.6%和6.1%；对具有新鲜排放特征VOCs的贡献分别为34.6%、38.4%、10.1%、8.5%和8.5%.长治市VOCs主要受本地机动车与燃煤源排放的影响，而LPG/ NG使用源与工艺过程源可通过区域传输影响本地环境VOCs.可见，有效控制本地机动车与燃煤源排放、加强市区周边LPG/NG使用与工艺过程源的联防联控，是降低长治市环境VOCs浓度与O₃生成的有效途径.

Source apportionment and chemical reactivity of VOCs based on clustering during summertime in Changzhi

To better understand sources and characteristics of volatile organic compounds (VOCs) pollution in Changzhi, a set of air samples were collected in summer 2017 to study the concentration and chemical reactivity (in the rate of OH radical loss) on ozone generation, and to identify anthropogenic sources of VOCs based on clustering analysis and positive matrix factorization model (PMF). Results revealed that the average concentration and chemical reactivity of total VOCs was 37.40μg/m³ and 5.07s^-1, respectively, with the mixing characteristic of the local fresh emissions and aged air masses after oxidation reaction. Five major anthropogenic sources of VOCs with their contribution were identified by PMF: vehicles exhaust (29.7%), coal combustion (29.2%), liquefied petroleum gas/natural gas (LPG/NG) usage (23.5%), industrial processes (11.6%), and solvent usage (6.1%). For fresh emissions, the contribution shares became 34.6%, 38.4%, 10.1%, 8.5%, and 8.5%, respectively. The results suggested that VOCs in Changzhi mainly came from local vehicles exhaust and coal combustion, but LPG/NG usage and industrial processes in neighboring regions could also influence local VOCs via regional transportation processes. Thus, to effectively control the local VOCs emission, a joint prevention and control effort of LPG/NG usage and industrial processes in the neighboring urban area around Changzhi is needed in addition of regulating local vehicles and coal combustion.