Development of Micro-Analysis for Simultaneous Multi-elements measurement of Environmental Samples

点击翻译按钮获取中文摘要

The best sampling and measurement conditions for the PIXE (Particle Induced X-ray Emission) and PIGE (Particle Induced Gamma-ray Emission) analyzes were investigated, especially in order to apply to the micro-analysis of samples collected in environment.1.Preparation of standard samples and calibration of PIXE :Two kinds of standard samples were prepared. They were used to establish the calibration method of the PIXE analysis and to test the sensitivity and accuracy of the PIXE analysis. It was confirsed that the elements with the atomic number larger than 19 (K) could be measured with high accuracy up to ng order.2.Sampling and handling procedure for PIXE analysis of atmospheric aerosols and liquid sample :Atmospheric aerosols are recommended to be classified at least into the fine and coarse fractions in the sampling. A two staked filter sampling method and a low pressure cascade impactor method were adopted for the 2 and 12 size ranges sampling, respectively. A part of aerosol samples and all of the liquid samples were divided into the soluble and insoluble fractions. Sampling and handling procedure proposed in this study was applied to study the characteristics of atmospheric aerosols and the dry and wet deposition mechanisms of air pollutants.3.Basic studies on the micro-analysis of lighter elements by PIGE :An irradiation chamber for the PIGE analysis was designed and produced. Using this chamber, the gammaray yield from the NaCl samples with different concentrations, the density distribution of carbon in wood samples and the discrimination of isotope were tested.4.Development of computer program to analyze the PIXE spectrum :Computer program that calculate the sensitivity surve, detection limit, mass thickness and the elemental concentration of samples was developed. It can cope with any sampling conditions and any irradiation and measurement conditions at the PIXE analysis.