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复杂句使用不错，句法规范；作者词汇基本功不错，高级词汇表达灵活熟练；采用了简单的衔接手法，行文流畅。
Atmospheric Particulate matter (Atmospheric Particulate Matters) is a variety of solid and liquid particles in the atmosphere quality floorboard. The atmospheric particles according to size which can be divided into: the total suspended particulate matter, dust, fly ash. Total suspended particles is suspended in the air, the air dynamics equivalent diameter 100 microns or less particulate matter. Its size is less than 100 microns, most of them under 10 microns, and scholars define it as the atmosphere of all solid particles diameter less than 100 microns. In total suspended particulate matter, the particle size of more than 10 microns particles, because of the large volume and quality under the gravity can quickly down to the earth's surface, this part of the particles known as dust, also known as the fallout, per unit area of heavy is one of the evaluation index of atmospheric pollution. But there are also scholars pointed out that the dust for aerodynamic. Particulate matter pollution and damage to itself the content of harmful components, phase fabric, micro particle morphology, particle size and the adsorption of poisonous and harmful substances such as closely related to the physical and chemical properties, so research the properties of atmospheric particulates, to reveal its environment and the harm of human body, formation mechanism, material sources, further understanding can inhale the environmental behavior of atmospheric particulates, have important role. Sichuan basin is located in China's southwest, wushan, dabashan mountain east and bordering the south and the yunnan-guizhou plateau, north of qinling mountains, west near the roof of the world on the Tibetan plateau. Chengdu plain is located in the sichuan basin, the flat (elevation between 442-750 - m). The sampling sites in chengdu university of technology buildings planted TSP sampler, 9 samples on a regular basis. Membrane filter before use in indoor incubator constant weight and accurately record and constant quality, sealed after weighing. To avoid dust on the ground, the influence of sample height is 5 ~ 10 m, sampling time for 24 h, a sampling period of continuous acquisition 5 d, at the same time record the sampling points of the atmospheric pressure, temperature, wind direction, wind speed and other basic meteorological conditions. Analyzed by weight method of total suspended particle concentration distribution characteristics, with HNO3 - HF - high pressure seal, with icp-ms analysis of particulate matter of Cu, Pb, zinc, Cd, Cr, Ni, V, Ti etc. The quality of the concentration. The results show that the [1] by measured the TSP annual average concentration of 0.2199 mg/m3, slightly more than the national standard, there are still problems with the description of chengdu east environment. 【 2 】 east of chengdu TSP atmospheric average mass concentration changes for winter > spring > autumn > summer, show obvious seasonal variation. [3] in atmospheric particulate matter, the large difference between two average concentration distribution of heavy metals: zinc content in the highest, lowest elements Cd. Among them the As content exceeds bid, As pollution phenomenon should be taken into consideration seriously. [4] in addition to the Cu, other maximum concentration of heavy metal elements in December, the minimum generally appear in the June, July and August. [5] of chengdu east air TSP concentration of Pb, zinc, Cr and Ni in seasonal variation characteristics are winter > spring > autumn > summer; Seasonal variation of Cu is spring > winter > summer > autumn. From the point of changing degree, Ni elements change is not obvious; Cu and Cr element has obvious seasonal variation; Zinc element and Pb element is most obvious seasonal changes. [6] of chengdu east atmospheric TSP concentration degree of size of each heavy metal element in the sequence of Cu > zinc > Pb > Cr > Ni. Cu, zinc and Pb element enrichment of serious, should be taken into consideration seriously.
