A nuclear microprobe with high spatial resolution and high analyti- cal sensitivity was applied to analyze atmospheric aerosol at five monitoring sites in Shanghai city. Meantime, a new pattern recognition technique, ...A nuclear microprobe with high spatial resolution and high analyti- cal sensitivity was applied to analyze atmospheric aerosol at five monitoring sites in Shanghai city. Meantime, a new pattern recognition technique, which used the micro PIXE spectrum of a single aerosol particle as its fingerprint, was developed to identify the origin of the particle. The results showed that the major contributors to the at- mosphere pollution were soil dust (31.6%), building dust (30.8%), and the next were vehicle exhaust (13.7%), metallurgic industry excrements (5.6%), oil combustion (5%) and coal combustion (2.3%). Besides these, about 10% of the particles could not be identified. Based on the cluster analysis of these particles, they could be divided into eight groups. By inference, they might belong to some sub-pollution sources from soil dust, building dust and metallurgic industry excrements. Moreover, some new pollution sources from tyres and chemical plants were also revealed.展开更多
The paper calculates and analyzes physical and chemical characteristics of total suspended particles （TSP）, including mass concentration, absorption coefficient, optical refraction index imaginary unit and chemical ...The paper calculates and analyzes physical and chemical characteristics of total suspended particles （TSP）, including mass concentration, absorption coefficient, optical refraction index imaginary unit and chemical composition based on observational data of atmosphere aerosol in Xi＇an and Nanjing from 1997 to 1999. Enrichment characteristic of TSP elements and sources of pollution are discussed via statistical treatment of enrichment factor of elements and correlation analysis. The result shows that aerosol particles exist remarkable differences in physical and chemical. The highest enrichment in TSP is Pb, Zn, S and As, which comes from different kinds of pollution.展开更多
The study on elemental speciation in atmospheric particulate matter (PM) is important for understanding the formation and origin of pollution and evaluating their toxicity. In this paper,the speci- ation of iron in at...The study on elemental speciation in atmospheric particulate matter (PM) is important for understanding the formation and origin of pollution and evaluating their toxicity. In this paper,the speci- ation of iron in atmospheric PM was investigated with extended X-ray absorption fine structure (EXAFS) spectra based on synchrotron radiation. The chemi- cal components of PM can be calculated by regres- sion analysis of EXAFS spectra. This is a non-destructive method. In order to have knowledge of the influence of chemical components on EXAFS spectra,we prepared a series of mixed reference samples,and proved the precision of method is good. The PM samples with different particle sizes and from different sampling sites were collected in Shanghai,China. The chemical components of the samples were calculated by regression analysis of EXAFS spectra. The results show that the iron in all PM samples mainly consist of Fe2O3,Fe3O4 and Fe2(SO4)3,but their proportions are different in dif- ferent samples. The changes of components among PM samples were observed preliminarily. The con- centrations of iron in the samples were determined by proton-induced X-ray emission (PIXE) technique. It is observed that the concentrations of iron in the sam- ples of iron and steel industrial district were much higher than those of other districts,and chemical components were also different from those of others.展开更多
基金Supported by National Natural Science Foundation of China (11030042)
文摘A nuclear microprobe with high spatial resolution and high analyti- cal sensitivity was applied to analyze atmospheric aerosol at five monitoring sites in Shanghai city. Meantime, a new pattern recognition technique, which used the micro PIXE spectrum of a single aerosol particle as its fingerprint, was developed to identify the origin of the particle. The results showed that the major contributors to the at- mosphere pollution were soil dust (31.6%), building dust (30.8%), and the next were vehicle exhaust (13.7%), metallurgic industry excrements (5.6%), oil combustion (5%) and coal combustion (2.3%). Besides these, about 10% of the particles could not be identified. Based on the cluster analysis of these particles, they could be divided into eight groups. By inference, they might belong to some sub-pollution sources from soil dust, building dust and metallurgic industry excrements. Moreover, some new pollution sources from tyres and chemical plants were also revealed.
文摘The paper calculates and analyzes physical and chemical characteristics of total suspended particles （TSP）, including mass concentration, absorption coefficient, optical refraction index imaginary unit and chemical composition based on observational data of atmosphere aerosol in Xi＇an and Nanjing from 1997 to 1999. Enrichment characteristic of TSP elements and sources of pollution are discussed via statistical treatment of enrichment factor of elements and correlation analysis. The result shows that aerosol particles exist remarkable differences in physical and chemical. The highest enrichment in TSP is Pb, Zn, S and As, which comes from different kinds of pollution.
基金the Chinese Academy of Sciences （approval code KJCX2-SW-No1） the National Natural Science Foundation of China （Grant No. 10490182）.
文摘The study on elemental speciation in atmospheric particulate matter (PM) is important for understanding the formation and origin of pollution and evaluating their toxicity. In this paper,the speci- ation of iron in atmospheric PM was investigated with extended X-ray absorption fine structure (EXAFS) spectra based on synchrotron radiation. The chemi- cal components of PM can be calculated by regres- sion analysis of EXAFS spectra. This is a non-destructive method. In order to have knowledge of the influence of chemical components on EXAFS spectra,we prepared a series of mixed reference samples,and proved the precision of method is good. The PM samples with different particle sizes and from different sampling sites were collected in Shanghai,China. The chemical components of the samples were calculated by regression analysis of EXAFS spectra. The results show that the iron in all PM samples mainly consist of Fe2O3,Fe3O4 and Fe2(SO4)3,but their proportions are different in dif- ferent samples. The changes of components among PM samples were observed preliminarily. The con- centrations of iron in the samples were determined by proton-induced X-ray emission (PIXE) technique. It is observed that the concentrations of iron in the sam- ples of iron and steel industrial district were much higher than those of other districts,and chemical components were also different from those of others.
