DEVELOPMENT OF METHODS FOR ANALYZING INORGANIC COMPONENTS IN AEROSOLS AND THEIR APPLICATION TO CHEMICAL CHARACTERIZATION OF ATMOSPHERIC AEROSOLS

利用SR - x射线微探针系统制备了单粒子分析光谱显微镜。该体系由μ-XANES的化学态分析和p -XRD的晶体结构分析组成。10keV x射线微束的空间分辨率为2 ~ 5μm， Ni的最小检出限为0.3fg。XRF产率的能量依赖性使得用特定的XANES光谱可以识别从Cr到Zn的元素的化学状态。在μ-XRD系统中，对样品进行角振荡，补偿光束位移，得到单个粒子的多个衍射指标。我们还开发了一种agf -氮双薄膜法，用于同时检测单个颗粒中的氯化物和硝酸盐离子。该系统被用于量化在日本和韩国两个偏远地点收集的个别科沙和非科沙气溶胶中的微量元素。与非科沙期相比，科沙期土壤中重金属（Mn、Ni、Cu、Zn）和土壤组分的质量显著增加。采用两种双薄膜法，从科沙入库开始进行了多次时间序列采样，研究了氯离子、硝酸盐离子和硫酸盐离子在单个颗粒中的混合状态。在2004年春季的科沙事件中发现，韩国的改性颗粒中形成组分以硫酸盐为主，而日本的改性颗粒中形成组分以硝酸盐为主。随着时间的推移，改性颗粒的百分比大致下降，同时含有氯化物和硝酸盐的颗粒在第一次采样时最大，之后显著下降。在改性粗颗粒中，硝酸盐是主要离子，同时含有硫酸盐和硝酸盐的颗粒较少。含有这三种离子的粒子几乎没有被检测到。

Spectromicroscopy using SR x-ray microprobe system was fabricated for single particle analysis. The system consists of elemental analysis by chemical state analysis of μ-XANES and crystal structure analysis by p,-XRD. The spatial resolution was 2-5μm and the minimum detection limit of Ni was 0.3fg for 10keV x-ray microbeam. The energy dependence of XRF yield enabled identification of the chemical states of elements from Cr to Zn with specific XANES spectra. In μ-XRD system, the sample was angularly oscillated with compensation of the beam displacements to obtain several indices of diffraction from a single particle. We have also developed a AgF-nitron double thin film method for simultaneous detection of chloride and nitrate ions in individual particles.The system was applied to quantify the ultra trace elements in the individual Kosa and non-Kosa aerosols collected at the two remote sites in Japan and Korea. We have demonstrated the remarkable mass increase of heavy elements (Mn, Ni, Cu, Zn) as well as soil components during Kosa event compared with non-Kosa period. Several time-series samplings were performed from the beginning of the Kosa incoming to investigate the mixing state of chloride, nitrate and sulfate ions in individual particles by two double thin film methods. It was revealed that sulfate constituted the majority of the formed components in the modified particles in Korea, while nitrate was the major component in Japan at Kosa event in the spring of 2004. Percentage of the modified particles roughly decreased with time and that of the particles containing both chloride and nitrate was largest at the first sampling with significant decrease after that time. In the modified coarse particles, nitrate was the dominant ions and particles containing both sulfate and nitrate were slightly detected. Particles containing all three ions were hardly detected.