A field measurement study of volatile organic compounds (VOCs) was performed in January 2015 in the urban areas of two of the most important cities of the Yangtze River Delta: Nanjing and Suzhou. The objectives of this study included comparing the characteristics of VOC concentrations, comparing the impacts of emissions on VOCs, using species ratios to assess air mass age, and evaluating ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAP) in air masses. The VOC concentrations in Nanjing (34.6 ± 5.8 ppbv) were higher than those of Suzhou (28.1 ± 5.6 ppbv). The most abundant VOC measured was ethane (6.6 ppbv in Nanjing and 3.6 ppbv in Suzhou). Relevant analysis shows that motor vehicle emissions in Suzhou were dominant, whereas industrial emissions in Nanjing also contributed to VOCs. During rush hour, the VOC concentrations in Nanjing were the highest (35.3 ppbv). The T/B ratio (0.92-1.79) for the two sites was observed to be relatively low in the other studied cities, indicating the source impact of traffic emissions in the two sites. Indicators X/B (0.26-0.39) and X/E (0.33-0.66) also confirmed an aging air mass was transported at the two sampling sites. According to principal component factor analysis results, vehicle emissions (44.8% in Nanjing and 30.6% in Suzhou) were the most important contribution to the two sites. Industrial sites were not only likely to experience industrial emissions but were affected by traffic emissions. Using the OFP method, both sites showed the largest percentage of alkenes (59.9% in Nanjing and 62.0% in Suzhou). When comparing SOAP, both sites showed an absolute majority of aromatics (97.6% in Nanjing and 98.3% in Suzhou). To control the formation of O3 and SOA in the two sites, it is necessary to reduce the concentration of alkenes and aromatics, respectively. By CPF analysis, pollutants transported from the SE and NE have significant effects on the Nanjing site. In the Suzhou, roads and industrial parks in the SE and S of Suzhou have significant impacts on the site.

中文翻译：

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长江三角洲两个城市站点南京和苏州的挥发性有机化合物的特征

2015年1月，在长江三角洲两个最重要的城市：南京和苏州，对挥发性有机化合物（VOC）进行了现场测量研究。这项研究的目标包括比较VOC浓度的特征，比较排放物对VOC的影响，使用物种比率评估空气质量年龄以及评估空气质量中的臭氧形成潜能（OFP）和次要有机气溶胶形成潜能（SOAP） 。南京的VOC浓度（34.6±5.8 ppbv）高于苏州（28.1±5.6 ppbv）。测得的最丰富的VOC是乙烷（南京为6.6 ppbv，苏州为3.6 ppbv）。相关分析表明，苏州的汽车排放量占主导地位，而南京的工业排放量也造成了挥发性有机化合物的排放。在高峰时段 南京的VOC浓度最高（35.3 ppbv）。在其他研究城市中，两个站点的T / B比（0.92-1.79）相对较低，这表明两个站点的交通排放对源产生的影响。指标X / B（0.26-0.39）和X / E（0.33-0.66）也证实了老化的空气在两个采样点被运输。根据主成分因子分析结果，车辆排放量（南京为44.8％，苏州为30.6％）是这两个地点的最重要贡献。工业场所不仅可能遭受工业排放，还受到交通排放的影响。使用OFP方法，两个站点都显示出最大的烯烃百分比（南京为59.9％，苏州为62.0％）。比较SOAP时，两个站点均显示绝对多数的芳族化合物（南京为97.6％，98％。苏州为3％）。为了控制两个位置中O3和SOA的形成，有必要分别降低烯烃和芳烃的浓度。通过CPF分析，从SE和NE运出的污染物对南京站点具有重大影响。在苏州，苏州东南和东南的道路和工业园区对该场地产生了重大影响。