| With the development of economy and standard of living, it's paid more and more attention to heavy metals in airborne particles, especially about composition of metal, concentration and distribution. The composition and source of airborne particles are so complicated that it's harmful to human body, especially heavy metals.The new methods for determination of trace As, Cd, Pb, Hg and Zn by hydride generation atomic fluorescence spectrometry (HG-AFS) were established. Based on determination results of different diameter particles in atmosphere from August of 2007 to July of 2008 in Baoding City, the concentration changes and size distribution characteristics of these particles were studied, on the other hand, the concentrations and their temporal variation of the heavy metals were examed; the soures of the heavy metals were also explored using enrich-ment factors and factor analysis.The result will have momentous academic and practice significance in estimating the harm to human body, environmental quality assessment and to table a proposal of polluted airborne particles.This thesis consists of five chapters as follows:Chapter 1 Based on the introduction of status quo in airborne particles, the analytical methods and technologies for heavy metals were reviewed. The effects of enhancing reagents on hydride generation and the release and elimination of interference were discussed. The concentration and distribution of metals in different diameter particles in atmosphere were researched. Also, the basic characteristics of airborne particles were summarized, such as radicalization, particle distribution and sedimentation velocity.Chapter 2 Based on determination results of different diameter particles in atmosphere from August of 2007 to July of 2008 in Baoding City, the concentration changes and size distributions characteristics of these particles were studied. Effects of meteorological conditions on atmospheric particles were discussed.The result showed that the suspended particulates concentration was higher. The results exhibited a distinct seasonal variation:the highest in winter and the lowest in summer. Good linear relationship between total suspended particulates (TSP) and PM10, PM5and PM2.5 was observed.Meteorological parameters such as air temperature, pressure and wind velocity, had directly influence on the particles in the air. The exceptive weathers such as fog, sand dust and rain have an important impact on particle matters.Rain plays an important role in the clean up of aerosols, especially of fine particles.Chapter 3 A new method for determination of trace As, Cd, Pb, Hg and Zn in different diameter particles of atmosphere by hydride generation atomic fluorescence spectrometry (HG-AFS) was established. The working mechanism of the hydride generation was discussed and the operation conditions such as acidity, potassium tetrahydroborate solution concentration, flow capacity of carrier gas and enhancing reagent were optimized. Under the optimized conditions, the detection limits of As, Cd, Pb,Hg and Zn were 0.168μg·L-1, 0.030μg·L-1,0.310μg·L-1,0.023μg·L-1,1.6μg·L-1.The proposed method has shown several advantages:fast digestion; high sensitivity and low lost.Chapter 4 Based on determination results of different diameter particles in atmosphere from August of 2007 to July of 2008 in Baoding City, the concentrations and their temporal variation of the heavy metals were studied. And the soures of the heavy metals were also explored using enrich-ment factors and factor analysis. The result showed that The concentration level sequence of five metal elements in the suspended particulates were Zn, Pb, As, Cd and Hg from high to low. Pb, Zn and Cd were enriched in the particle meter of≤2.5μm; As had a similar distribution in fine particle meters and coarse particle meters; Hg had an average distribution in PM2.5, PM2.5-5 and PM5-10.The results showed that the concentrations of Pb and Hg in winter were higher than in summer, while the concentrations of Zn and Cd showed a reversed pattern. However, there wasn't obviously change of As.Chapter 5 The summing-up and more prospects of airborne particles were showed in this chapter.
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