| The composites of atmospheric dust particles are the important target for environmental monitoring. Harmful levels of atmospheric particles is closely related to physical properties, such as their contents of harmful components, micro-particle morphology, particle size and the absorption of harmful substances. In addition, the atmospheric particles are the transport carrier and reaction bed of other pollutants, besides themself are harmful substances. Therefore, to study the physical properties and chemical composition of atmospheric single-particles is of great significance to the prevention of heavy metal pollution, protect human health, and studies of urban air pollution.Observation of small particles and the measurement of the element content in the small areas, the conventional statistical methods can not meet the requirements. In present, the research of atmospheric single-particles is to mainly analyze physics characteristics, chemical characteristics, composition, morphological distribution of particles and the relationship between particles and the surrounding environment through the combining method of EDX—SEM and micro-probe techniques. However, quantitative analysis of the various elements is rare, especially heavy metals.This thesis comes from the "863 Project""Harbour in situ X-ray probe analysis system develop"(2006AA09ZZ19) and the "China Geological Survey Project" (1212010706501), and it applies Micro-beam Micro-district X fluorescence probe analyzer to microanalysis of atmospheric particles. The analyzer's X-ray has high brightness, high collimation, which make its sensitivity greatly increased. The fluorescence focal spot diameter produced by X-ray tube in the analyzer is about 34μm, which makes the analyzer provide accurately the information of particle appearance in sample micro-area, and can analyze quantitativlly more trace elements within the sample. The paper aims to solve quantitative problems of carve Elements in the atmospheric single-particle, to introduce a new measurement tool for the environmental monitoring, also to provide reference data for the developped of field micro analyzer.In the paper experiment, we use the IED-6000 Micro-beam Micro-district X fluorescence probe analyzer developed by our institute. To use the developed fundamental parameters quantitative analysis procedures for micro X-ray analyzer on the basic of the research in the fluorescence intensity theory, the basic theory of fundamental parameter method and the fitting formula of the various basic parameters; and to configure baseline samples; and to calibrate quantitative analysis procedures of the instrument though the theoretical calculation of values of parameters such as the first fluorescence intensity, the second fluorescence intensity, the relative fluorescence intensity, the fluorescence intensity of elements of standard sample and all the necessary basic parameters; so to implement to analyze quantitativlly main inorganic components of single particle in the environmental samples contained.This article focuses the preliminary study of inorganic composition of atmospheric single particles, origin and distribution form Chengdu University of Technology campus and around the junction. On the one hand, on a theoretical point of view analyze atmospheric respirable particles matter in accordance with generally applicable model of source analysis, first put the focus on attention from the source to a local atmospheric environment affected by the pollution, that is the receptor, and infer the source of particulate matter by analyzing the particles collected in the receptor samples, then determine the contribution value of various types of environmental pollution to the receptor by environmental monitoring of atmospheric particles and microscopic analyzing. On the other hand, on the experimental point of view explore a new method of collection and analysis of atmospheric particulate matter, and collect atmospheric dust samples using manual methods, and measure quantitativlly the content of main element particles contained in the samples under the condition of samples flattened on grass without any chemical treatment. Finally, to analyze the data using related software, and to draw the map of element content distribution in Chengdu University of Technology campus and around the intersection, and to reveal the source of atmosphere single particles, formation mechanism and distribution characteristics in the school and the near, and to further understand the environmental behavior of respirable atmospheric particles, so to provide the basis for elimination the harm of atmospheric particles.In summary, Micro-beam Micro-district X-ray probe technology is effective means of elemental composition analysis in the environmental monitoring. The method can achieve rapid quantitative analysis of many elements in a atmosphere single particle without complex processing of sample, and the method is of great significance in the areas of micro-area elemental analysis ,such as environmental monitoring, mineral particles.
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