Department of Environmental Science and Technology, School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Shaanxi, China.
Sci Total Environ. 2010 Mar 1;408(7):1621-7. doi: 10.1016/j.scitotenv.2009.11.061. Epub 2009 Dec 29.
PM(2.5) (particle with an aerodynamic diameter less than 2.5microm) was measured in different microenvironments of Hong Kong (including one urban tunnel, one Hong Kong/Mainland boundary roadside site, two urban roadside sites, and one urban ambient site) in 2003. The concentrations of organic carbon (OC), elemental carbon (EC), water-soluble ions, and up to 40 elements (Na to U) were determined. The average PM(2.5) mass concentrations were 229+/-90, 129+/-95, 69+/-12, 49+/-18microg m(-3) in the urban tunnel, cross boundary roadside, urban roadside, and urban ambient environments, respectively. Carbonaceous particles (sum of organic material [OM] and EC) were the dominant constituents, on average, accounting for approximately 82% of PM(2.5) emissions in the tunnel, approximately 70% at the three roadside sites, and approximately 48% at the ambient site, respectively. The OC/EC ratios were 0.6+/-0.2 and 0.8+/-0.1 at the tunnel and roadside sites, respectively, suggesting carbonaceous aerosols were mainly from vehicle exhausts. Higher OC/EC ratio (1.9+/-0.7) occurred at the ambient site, indicating contributions from secondary organic aerosols. The PM(2.5) emission factor for on-road diesel-fueled vehicles in the urban area of Hong Kong was 257+/-31mg veh(-1) km(-1), with a composition of approximately 51% EC, approximately 26% OC, and approximately 9% SO(4)(=). The other inorganic ions and elements made up approximately 11% of the total PM(2.5) emissions. OC composed the largest fraction (approximately 51%) in gasoline and liquid petroleum gas (LPG) emissions, followed by EC (approximately 19%). Diesel engines showed higher emission rates than did gasoline and LPG engines for most pollutants, except for V, Br, Sb, and Ba.
2003 年，在香港的不同微环境（包括一个城市隧道、一个港陆边界路边站点、两个城市路边站点和一个城市环境站点）中测量了 PM(2.5)（空气动力学直径小于 2.5 微米的颗粒）。测定了有机碳（OC）、元素碳（EC）、水溶性离子和多达 40 种元素（从 Na 到 U）的浓度。在城市隧道、跨界路边、城市路边和城市环境环境中，PM(2.5)的平均质量浓度分别为 229+/-90、129+/-95、69+/-12、49+/-18μg m(-3)。碳质颗粒（有机物质[OM]和 EC 的总和）是主要成分，分别占隧道排放物的 82%左右、三个路边站点的 70%左右和环境站点的 48%左右。OC/EC 比值在隧道和路边站点分别为 0.6+/-0.2 和 0.8+/-0.1，表明碳质气溶胶主要来自车辆尾气。环境站点的 OC/EC 比值较高（1.9+/-0.7），表明有二次有机气溶胶的贡献。香港市区道路柴油车的 PM(2.5)排放因子为 257+/-31mg veh(-1) km(-1)，其组成约为 51%的 EC、约 26%的 OC 和约 9%的 SO(4)(=)。其他无机离子和元素约占总 PM(2.5)排放量的 11%。OC 在汽油和液化石油气（LPG）排放中占最大比例（约 51%），其次是 EC（约 19%）。除 V、Br、Sb 和 Ba 外，与汽油和 LPG 发动机相比，柴油发动机对大多数污染物的排放率更高。
