中文摘要：

为研究日喀则不同粒径大气颗粒物中水溶性无机离子的组成特征,利用Andersen分级撞击式采样器在夏、冬季进行大气颗粒物分级采样,采用离子色谱测定NH＋4、Ca2＋、K＋、Mg2＋、Na＋、SO2-4、NO-3和Cl-等8种离子浓度.结果表明,夏、冬季总离子浓度分别为9648±3030、4925±1138 ng·m-3.夏季离子浓度高低顺序为Cl-﹥Ca2＋﹥NH＋4﹥Na＋﹥SO2-4﹥NO-3﹥K＋﹥Mg2＋,Cl-、Ca2＋、NH＋4和Na＋占总离子浓度的比重为74.9%;冬季水溶性无机离子浓度高低顺序为Cl-﹥SO2-4﹥NH＋4﹥NO-3﹥Ca2＋﹥Na＋﹥K＋﹥Mg2＋,Cl-、SO2-4、NH＋4和NO-3占总离子浓度的比重为88.0%.夏、冬季大气颗粒物中所有水溶性无机离子的粒径分布均成双峰型.夏季,大气颗粒物中SO2-4与Mg2＋（r=0.951）、Ca2＋（r=0.947）,NO-3与Mg2＋（r=0.904）、Ca2＋（r=0.843）,在0.01水平（双侧）上均显著相关;冬季,细粒子中K＋与Cl-（r=0.740）、SO2-4（r=0.929）及NO-3（r=0.920）,在0.01水平（双侧）上显著相关.

英文摘要：

To investigate the size distributions of water-soluble inorganic ions in PM in Shigatse,samples were collected by Thermo Scientific Andersen impactor in summer and winter. Eight watersoluble inorganic ions,including NH＋4,Ca2 ＋,K＋,Mg2 ＋,Na＋,SO2-4,NO-3and Cl-were analyzed by IC. The results showed that concentrations of all ions were 9648 ± 3030 ng·m- 3in winter and 4925 ± 1138 ng·m- 3in summer. Variations of ion concentrations were observed in the following order： Cl-﹥ Ca2 ＋﹥ NH＋4﹥ Na＋﹥ SO2-4﹥ NO-3﹥ K＋﹥ Mg2 ＋in summer,and Cl-﹥ SO2-4﹥ NH＋4﹥ NO-3﹥ Ca2 ＋﹥ Na＋﹥ K＋﹥ Mg2 ＋in winter. Concentrations of Cl-,Ca2 ＋,NH＋4and Na＋accounted for 74. 9% of all the ions in PM in summer,and those of Cl-,SO2-4,NH＋4and NO-3accounted for 88. 0% of all the ions in PM in winter. Correlations of SO2-4and Mg2 ＋（ r = 0. 951）,Ca2 ＋（ r = 0. 947） were significant at the 0. 01 level,and those of NO-3and Mg2 ＋（ r =0. 904）,Ca2 ＋（ r = 0. 843） were also significant at the 0. 01 level in summe. Correlations of K＋and Cl-（ r = 0. 740）,SO2-4（ r = 0. 929）,NO-3（ r = 0. 920） were significant at the 0. 01 level.