Size-resolved organic aerosols and their sources in the urban,mountain and marine atmospheres over East Asia
作者单位：Institute of Low Temperature ScienceHokkaido University
会议名称：《第十届全国气溶胶会议暨第六届海峡两岸气溶胶技术研讨会》
会议日期：2009年
学科分类：07[理学] 070602[理学-大气物理学与大气环境] 0706[理学-大气科学]
关 键 词：Organic aerosols n-Alkanes,PAHs and Hopanes Molecular compositions Size distributions Urban,mountain and marine atmospheres
摘 要：Size-segregated(9 stages)n-alkanes,polycyclic aromatic hydrocarbons(PAHs)and hopanes in the urban(Baoji city in inland China),mountain(*** in east coastal China)and marine(Okinawa Island, Japan)atmospheres over East Asia were studied using a GC/MS *** of n-alkanes (1698±568 ng m-3 in winter and 487±145 ng m-3 in spring),PAHs(536±80 and 161±39 ng m-3),and hopanes(65±24 and 20±2.4 ng m-3)in the urban air are 1?2 orders of magnitude higher than those in the mountain aerosols and 2?3 orders of magnitude higher than those in the marine *** ratios of n- alkanes,PAHs and hopanes clearly demonstrate coal-burning emissions as the major source of the determined organic *** distributions of fossil fuel derived n-alkane,PAHs and hopanes were found as a unimodal in most cases,peaking at 0.7?1.1μm *** contrast,plant wax derived n-alkanes present a bimodal distribution with two peaks at the sizes of 0.7?1.1μm and4.7μm in the summer mountain and spring marine *** the three types of samples,geometric mean diameter(GMD)of the determined organics in fine mode(2.1μm)was the smallest(av.0.63μm in spring)in the urban samples and the largest(1.01μm)in the marine samples,whereas the GMD in coarse mode(≥2.1μm)was smallest (3.48μm)in the marine aerosols and largest(4.04μm)in the urban *** fine mode of GMDs in the urban and mountain samples were larger in winter than in spring and ***,GMDs of 3-and 4- ring PAHs were larger than 5-and 6-ring PAHs in the three types of *** differences in GMDs may be interpreted by coagulation and repartitioning of organic compound during a long range transport from the inland continent to the marine site,suggesting that the size changes arising from these physical processes must be included in climate models in relevant to organic aerosols