Ion Chemical Characteristics And Elements Of Morphological Characteristics In China’s Central

In recent years, with the rapid growth of economy and population, the problem of air pollution becomes more and more serious. At the same time, this kind of condition has brought many negative effects to people’s life and work. Air quality is paid more and more attention from all walks of life, therefore, the study of the chemical composition of atmospheric aerosols has become a very effective way to solve the air pollution problem.In this paper, during the winter in January 2014 to February, 67 snow samples were collected(including blank samples) in Yili, Zhengzhou, Q ingdao, Shijiazhuang, Jiaxiang, Nanjing, Hangzhou, Wuhan, Ling’an and Guangde. Water soluble ions in the snow as the main line, a method was developed for the determination of snow in a sample of 5 cations, including K+, Na+, Ca2+, Mg2+, NH4+, and 7 kinds of inorganic anions, including F-, C l-, Br-, NO2-, NO3-, PO43-, SO42-, and 3 kinds of organic acid radical anions, including HCOO-, CH3COO-, C2O42- by IC. Then combined with laboratory analysis and model analysis, we study its spatial distribution, composition and source. In view of bromine and iodine species in snow, this paper also has done a research on the shallow level. The results showed as follows:(1) Rapid determination method of snow samples by ion chromatography is established, the test included five kinds of cation(K+, Na+, Ca2+, Mg2+, NH4+) and 7 kinds of inorganic anion(F-, Cl-, Br- and NO2-, NO3-, PO43-, SO42-) and three kinds of organic acid radical anion(HCOO-,CH3COO-,C2O42-). The detection limit of five kinds of cation is between 0.0017 and 0.0081 μg/m L, the detection limit of ten kinds of anion is between 0.34 and 4.64 μg/L. Except PO43- standard addition recovery rate at 76.5%, the rest of each ion standard addition recovery rate is between 80%~130%.(2) In china’s central and eastern regions, the average ion content in the snow from high to low order: SO42->Na+﹥NH4+﹥Ca2+﹥K+﹥NO3-﹥Mg2+﹥Cl-﹥HCOO-﹥CH3COO-﹥NO2-﹥F-﹥C2O42-﹥Br-﹥PO43-。(3)The level of 12 cities’ total ion concentration is roughly consistent with city air quality index. Shijiazhuang, Xi’an, Zhengzhou’s AQI and ion content were higher; Qingdao, Nanjing, Yili, Hangzhou and Lin’an’s AQI and ion content were lower. The content of the same ion in different city has a large difference. In the snow sample were collected, the concentration of each ion in Xi’an, Shijiazhuang and Lanzhou were relatively high. In Xi’an’s samples, the concentration of Ca2+, K+, Mg2+, Na+, NH4+ is the highest in all cities.(4) In different functional areas, the average concentration of cations: Business district > industrial zone > cultural and educational area > the suburban area. Compared with other functional areas, the concentration of each ion in the business district are relatively high. Probably surrounded by traffic intensive areas, automobile exhaust emissions is relatively large, resulting in a higher ion concentration in this area.(5) The water-soluble ion in the snow source resolution, studies have shown that: SO42- are highly enriched in oceans and crust, human source such as coal emissions may be the important reason for the high concentration. In Q ingdao, Zhengzhou, Lanzhou’s snow samples, Cl- mainly from sea salt aerosol. Through backward trajectory analysis, we found that during two times snowfall, the leading air mass was NW air mass, this air mass is continental air mass, which carrying large amounts of terrigenous material in the transfer process, have an important impact on the chemical composition of snow.(6) Using ICP-MS testing the total amount of bromine and iodine in the snow samples, statistical analysis showed that the concentration of bromine and iodine was highest in Shijiazhuang, and was the lowest in Hangzhou and Lin’an. And the concentration of bromine and iodine was the highest in the industrial area and was lowest in the suburbs. Using online combined of HPLC-ICP-MS determination of bromine and iodine species in the snow samples, we found that except in Lanzhou detected IO3-, the rest of the cities were only detected I- and Br-, and the content of Iis up to 51 percent of the total iodine, the content of Br- is up to 94 percent of the total bromine.