Source And Characteristics Of Chemical Composition Of PM_2.5 Southern Atmospheric In Winter In Urumqi

In recent years, with the rapid development of China's economic construction, the rapid growth of urban population made energy consumption of the coal-based cities show a rising trend, thereby increasing the city's air pollution. The southern atmosphere of Urumqi in winter is as the object on this study, to investigate the concentrational distribution and sources of its PAHs, heavy metals, water-soluble inorganic ions. The results will provide basic data to assess exposure characteristics health effects of the PAHs, heavy metals,water-soluble inorganic ions in Urumqi Southern PM_2.5 and, the in-depth analysis of its sources will provide scientific basis.to control PAHs, heavy metals, water-soluble inorganic ions in Urumqi atmosphere.From December of 2011 ?former coal to gas? and from October of 2012 to March of 2013 ?after coal to gas? in the new instructed college headquarters use a large volume sampler for the collection of samples of atmospheric particulate matter PM_2.5. Reference to method of the U.S. EPA-610, using chromatography-mass spectrometry ?GC-MS? technique on 17 kinds of PAHs priorities conducts a quantitatively analysis and discusses the concentrational distribution and sources of PAHs. The results showed that:during the sampling?after coal to gas? the daily average concentration range of E17PAHs is about 641.78?1138.35ng/m³, mass concentration range of PM_2.5 is about 55.78?481.43?g/m³. The molecular of PAHs with high weight, high ring acounted for the the major part, in which 4 ring,5 rings,6 rings,accounted for the higher content,respectively representing 32.64%,24.41%,17.85%of total sum to 74.9%. And with small molecular weight, and low ring like 2,3 ring respectively represent3.51%,13.89% of total, sum to17.4% in total. From the constrast ratio of the distribution and stable isomer of different ring PAHs, it can be seen to the PAHs atmospheric pollution of south Urumqi in winter are also mainly from the high-temperature combustion of fossil fuels, trees, grass and coal. The concentration range of Bap from the test results of polycyclic aromatic hydrocarbons in PM_2.5 is 0.81?18.93 ?ng m-3?. It is noteworthy that the Bap's concentration on 22nd of February in 2013 is 0.81 ?ng m-3?, the concentration of Bap, on the other sampling days, are over the air quality standards of the World Health Organization ?WHO?,which is about in Bap,1 ngm-3.Using the dual channel atomic fluorescence spectrometry ?ACP-AAS? and atomic absorption spectroscopy ?AAS? analyze the 10 kinds of heavy metals in PM_2.5 sample collected at Xinjiang University sampling points,conducting an analysis on the concentrations of heavy metals. The analysis showed that the concentrations range of heavy metal in the sampling period from 16th of October in 2012 to 5th of March in 2013 was 1.18?38.52?g/m³;the detected concentration order of 10 kinds of heavy metals of Urumqi atmosphere in winter was Fe> Zn> Ni> Mn> Cu> Cr> Pb> As> Cd> Hg. the content of Fe is quiet high rather than the content of other heavy elements, with an average of 7.16?g/m³, the lowest content is Hg, with an average of 0.0012?g/m³.Using the EPA PMF 3.0 software to conduct an analysis on the sources of heavy metals. The results showed that the main air pollution of southern Urumqi atmosphere PM_2.5 in winter is from metal heavy industry, coal and oil combustion and metal smelt and the dust.The concentration range of the nine kinds of water-soluble inorganicions detected By HPLC is 21.71?104.723?g/m³, NO3-,SO42- and NH4+ among the nine water-soluble inorganic ions had larger content. They are respectively accounting for 13.16%,47.22%,16.89% of the total water-soluble inorganic ion concentration, which is about 77.27%; and for 4.15%,14.55%,0.21% of total PM_2.5 mass, which is about 18.91%. In this study, the range NO3-/SO42- in the winter is from 0-0.66, all of the weight ratio of NO3-/SO42- is below 1, this indicated Urumqi atmosphere mainly is impacted by stationary sources such as power plants, industrial emissions and other emissioned pollutants.In this study, PM_2.5 the distrubution order of heavy metals,, and water-soluble inorganic ions in PM_2.5 is soluble ions> Heavy Metal> polycyclic aromatic hydrocarbons, respectively accounting for 28.53%,4.61%,0.41% of the total concentration of PM_2.5.