Vertical differences in the composition of PM10 and PM2.5 in the urban atmosphere of Osaka, Japan
Vertical differences in the composition of PM10 and PM2.5 in the urban atmosphere of Osaka, Japan
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DOI：
10.1016/j.atmosenv.2005.09.004
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发表时间：
2005-12
影响因子：
5
通讯作者：
K. Sasaki;K. Sakamoto
中科院分区：
文献类型：
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作者：
K. Sasaki;K. Sakamoto
使用日本大阪的一座建筑物对 PM10 和 PM2.5 悬浮颗粒的垂直差异进行了研究。 2002 年 8 月 5 日至 9 日和 12 月 2 日至 6 日期间，在建筑物屋顶（距地面 200 m）和地面采集了样品。除了测定样品质量外，还分析了主要化学成分的浓度，包括元素碳 (EC) 和有机碳 (OC)。 200m处采集的样品颗粒质量浓度低于地面采集的样品。 “其他”物种，定义为总颗粒质量与测量物种质量总和之间的差异，主要解释了夏季质量浓度的垂直差异，而 EC 和 OC 是冬季的主要贡献者。同时观测到的相对湿度垂直剖面表明，夏季采样期间地面相对湿度高于200m处。因此，地面收集的样品中“其他”物种的较高浓度很可能是由于颗粒的潮解成分吸收了水而造成的。冬季采样期间的垂直温度剖面表明，冬季稳定的气象条件导致一次颗粒物（主要是汽车尾气排放）的积累，导致地面EC和OC浓度较高。
Vertical differences in PM10and PM2.5suspended particles were investigated using a building in Osaka, Japan. Samples were collected on the roof of the building (200m above ground level) and on the ground during 5–9 August and 2–6 December 2002. In addition to determination of sample mass, concentrations have been analyzed for major chemical components including elemental carbon (EC) and organic carbon (OC). Particle mass concentrations of the samples collected at 200m were lower than those collected on the ground. “Others” species, defined as the difference between the total particle mass and the sum of the masses of the measured species, dominantly accounted for the vertical difference in mass concentrations in summer, whereas EC and OC were the major contributors in winter. Vertical profiles of relative humidity observed simultaneously indicated that relative humidity on the ground was higher than that at 200m during the summer sampling period. Hence, it is likely that the higher concentrations of “others” species in the samples collected on the ground were probably caused by water having been absorbed by deliquescent components of the particles. Vertical temperature profiles during the winter sampling period suggested that stable meteorological conditions in winter resulted in the accumulation of primary particles, mainly emitted from vehicle exhaust, leading to the high concentrations of EC and OC on the ground.