Mei De-Qing, Zhu Zong-Ning, Sun Tian-Shuo, Wang Xiang-Li, Mei Cong-Wei, Xiao Zheng-Zheng
School of Automobile and Traffic Engineering, Jiangsu University, Zhenjiang 212013, China.
School of Mechanical Engineering, Nantong University, Nantong 226019, China.
Huan Jing Ke Xue. 2019 Jan 8;40(1):114-120. doi: 10.13227/j.hjkx.201807074.
Characterization of the size distribution and carbon components in particulates has become important for identifying the particulates in the atmosphere. The size distribution and carbon components of atmospheric particulate matter from motor vehicles in different regions were analyzed by using Micro-orifice uniform deposition impactors (MOUDI) and the organic carbon/elemental carbon (OC/EC) analyzer. With increasing particle size, the mass concentration of raw diesel/gasoline decreases. The highest mass concentration of particles collected near the chimney of an engine laboratory was observed for particle sizes ranging from 0.32-0.56 μm, while particles with sizes from 1.0-1.8 μm in the basement garage showed the most mass fractions. The OC1, OC2, and OC3 were the major parts of the OC contents in raw diesel particles. The EC2 was the main part of EC. The atmospheric particles collected in typical regions contained more OC3 and OC4. EC1 was the main part of EC in particles collected from the basement garage. The OC/EC ratios of raw diesel particles ranged from 0.92 to 2.50. The OC/EC ratios of particles collected near the chimney of an engine laboratory ranged from 1.40 to 2.53 and that of particles collected in the basement garage ranged from 2.36 to 4.82. Moreover, the OC/EC ratios in particles collected in the basement garage normally exceeded 2.0 and reached 4.82 at the largest size, which implies that many secondary particles were generated in the basement garage. The above-mentioned characteristics provide references that are beneficial for the identification of particulates in the atmosphere originating from motor vehicles.
颗粒物尺寸分布和碳成分的表征对于识别大气中的颗粒物变得至关重要。使用微孔均匀沉积冲击器（MOUDI）和有机碳/元素碳（OC/EC）分析仪分析了不同地区机动车排放的大气颗粒物的尺寸分布和碳成分。随着粒径增大，原始柴油/汽油的质量浓度降低。在发动机实验室烟囱附近收集的颗粒物，粒径在0.32 - 0.56μm范围内时质量浓度最高，而在地下车库中，粒径为1.0 - 1.8μm的颗粒物质量分数最高。OC1、OC2和OC3是原始柴油颗粒中有机碳含量的主要部分。EC2是元素碳的主要部分。在典型区域收集的大气颗粒物含有更多的OC3和OC4。地下车库收集的颗粒物中，EC1是元素碳的主要部分。原始柴油颗粒的OC/EC比值在0.92至2.50之间。发动机实验室烟囱附近收集的颗粒物的OC/EC比值在1.40至2.53之间，地下车库收集的颗粒物的OC/EC比值在2.36至4.82之间。此外，地下车库收集的颗粒物的OC/EC比值通常超过2.0，在最大粒径时达到4.82，这意味着地下车库中产生了许多二次颗粒物。上述特征为识别大气中机动车来源的颗粒物提供了有益的参考。
