Hygroscopic property of water-soluble organic-enriched aerosols in Ulaanbaatar, Mongolia during the cold winter of 2007
Hygroscopic property of water-soluble organic-enriched aerosols in Ulaanbaatar, Mongolia during the cold winter of 2007
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DOI：
10.1016/j.atmosenv.2011.02.055
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发表时间：
2011-05
影响因子：
5
通讯作者：
Jinsang Jung;Y. J. Kim;S. G. Aggarwal;K. Kawamura
中科院分区：
文献类型：
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作者：
Jinsang Jung;Y. J. Kim;S. G. Aggarwal;K. Kawamura
利用吸湿性串联差分迁移率分析仪（H-TDMA）研究了2007年寒冷冬季在蒙古乌兰巴托一个城市站点（47.92°N, 106.90°E，海拔~ 1300m）收集的大气气溶胶的水溶性物质提取物的吸湿性。动态形状校正因子（χ），即实验室生成的水溶性物质（WSM）对非球形气溶胶颗粒的实际阻力与等效体积球体的实际阻力之比为1.09-1.38（平均值1.23±0.10），表明WSM产生的颗粒高度非球形。在85% RH条件下，迁移率直径的减小可导致吸湿生长因子低估约11%。85% RH条件下，WSM（初始干燥粒径=100nm）的吸湿生长因子（g(85%)）为1.32 ~ 1.50（平均1.40±0.06），即85% RH条件下的粒径与RH<10%条件下（初始干燥粒径）的比值。利用ZSR （Zdanovskii-Stokes-Robinson）方法和热力学气溶胶无机模型（AIM），从WSM测量的g（RH）中反演了水溶性有机质（WSOM）的g（RH）。研究发现，WSOM的g（85%）在1.11 ~ 1.35（平均g 1.22±0.08）之间，与生物质燃烧气溶胶的g值相当。
The hygroscopic properties of the water-soluble matter extracts of atmospheric aerosols collected at an urban site (47.92° N, 106.90° E, ∼1300m above sea level) in Ulaanbaatar, Mongolia during the cold winter of 2007 were investigated using a hygroscopicity tandem differential mobility analyzer (H-TDMA). Dynamic shape correction factor (χ), the ratio of the actual drag force on a non-spherical aerosol particle to that on a sphere of equivalent volume, of the laboratory generated water-soluble matter (WSM) was found to be 1.09–1.38 (avg. 1.23±0.10), implying that particles generated from the WSM are highly non-spherical. The reduction in the mobility diameter can cause ∼11% underestimation in a hygroscopic growth factor at 85% RH. The hygroscopic growth factors at 85% RH (g(85%)), defined as the ratio of the particle diameter at 85% RH to that at RH<10% (initial dry diameter), of the WSM (initial dry particle diameter=100nm) were 1.32–1.50 (avg. 1.40±0.06). The g(RH) of the water-soluble organic matter (WSOM) was retrieved from the measured g(RH) of the WSM and using the ZSR (Zdanovskii–Stokes–Robinson) approach and the thermodynamic aerosol inorganic model (AIM). We found that the g(85%) of the WSOM were in the range of 1.11–1.35 (avg. 1.22±0.08), which are comparable to those of the biomass burning aerosols.