乌鲁木齐不同分级气溶胶理化特征及其对大气消光的影响  

Physicochemical Characteristics of Aerosols and Its Influence on Atmospheric Extinction in Urumqi

作　　者：韩茜[1,2,3] 魏文寿[1] 刘新春[1,2,3] 钟玉婷[1,2,3] 

机构地区：[1]中国气象局乌鲁木齐沙漠气象研究所,新疆乌鲁木齐830002 [2]新疆树木年轮生态实验室,新疆乌鲁木齐830002 [3]中国气象局树木年轮理化研究重点开放实验室,新疆乌鲁木齐830002

出　　处：《沙漠与绿洲气象》2015年第6期68-72,共5页Desert and Oasis Meteorology

基　　金：中国沙漠气象科学研究基金项目(Sqj2012009);公益性科研院所基本科研业务费专项项目(IDM201205);国家科技支撑计划(2014BAC16B04)共同资助

摘　　要：2010年初采暖季,应用FA-3型气溶胶粒度分布采样器在乌鲁木齐市天山区对粒径在10μm以下的气溶胶分九级进行采样,并应用ICS3000离子色谱仪对其进行离子成分测定,结合同期AE-31型黑碳仪和Aurora-1000型积分浊度计测量所得的吸收系数和散射系数数据进行分析。研究结果表明,乌鲁木齐冬季气溶胶质量浓度0级(9.0~10μm)至2级(4.7~5.8μm)逐渐减小,2~5级(1.1~2.1μm)逐渐增至最大值,5级到8级(亚微米级)又逐渐减小。离子总浓度的分布与气溶胶质量浓度类似,6级(0.65~1.1μm)吸附可溶性离子能力最强,出现总离子浓度的峰值。各离子除Ca^(2+)和Mg^(2+)分布于粗模态外,SO_4^(2-),Na^+,NH_4^+,NO_3^-,Cl^-和K^+均在5~6级达到峰值。细粒子质量浓度远大于粗粒子,且吸附可溶性离子的能力也远大于粗粒子。消光系数与PM10,PM2.5,PM1.0和PM2.5~10的回归分析表明,用PM2.5质量浓度来模拟消光更有意义。采用多元线性逐步回归的方法分析不同粒径段上化学成分与气溶胶散射系数的关系,只有1.1~2.1μm和0.65~1.1μm这两个分级的硫酸盐和铵盐进入回归公式,可见这两分级的硫酸盐和铵盐对消光系数的贡献最大。In heating period in early 2010, FA-3 aerosol size distribution sampler was used tocollect aerosols with the nine graded membranes for particle size less than 10μm, and samplemembrane ionic composition was analyzed using ICS3000 ion chromatograph, combined with theabsorption coefficient and scattering coefficient measured by AE-31 Aethalometer and Aurora-1000 Nephlometer in the same period, the results showed as follows. The mass concentration of 0th grade（9.010 μm）decreased to 2nd grade（4.75.8 μm）, the 2nd grade peak value reached at 5thgrade（1.1 2.1 μm）, and then gradually decreased to 8th grade（sub-micron grade）. Thedistribution of total ionic concentration was similar to aerosol mass concentration, the 6th grade（0.651.1μm）had the strongest capacity to absorb ion, the peak value of total ionic concentrationoccurred in this grade. Except that the ions of Ca2＋and Mg2＋occurred at coarse mode, SO42-, theions of Na＋, NH4＋, NO3-, CL-and K＋reached peak at 5-6th grades. The mass concentration of fineparticles is much higher than coarse particles, and the absorption capacity was also higher than thatof coarse particles. The regression analysis between bext, and PM10, PM2.5, PM1.0 and PM2.5 10were conducted, respectively. The results showed that the regression equation of PM2.5 and bexthad the highest coefficient of determination（R 2=0.971）,which means PM2.5 can be used tosimulate bext better than other factors. Using multiple linear stepwise regression method x betweenscattering coefficient and chemical composition in 9 grade aerosols, only the SO42-in 1.1 2.1 μmand NH4＋ in 0.65 1.1 μm entered into the equations, with two coefficient of determination（R 2=0.959）, which means the SO42-in 1.1 2.1 μm and NH4＋ in 0.65 1.1 μm contribute most toatmospheric extinction.

关 键 词：分级采样 气溶胶 离子成分 大气消光 

分 类 号：X513[环境科学与工程—环境工程]