Chemical features and the mechanism of the preferential elution of the major ion in acidic snow melting water by acid shock

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To clarify the realities of an acid snow in Japan, snow pit studies was carried out at several places in Hokkaido, and Honshu in Japan, and the snowfall sample was able to be obtained. Moreover, the precipitation once a day was gathered throughout the year at this school in Nagaoka City. Regional differences and elevation - differences could be understood in distribution of acid substances in snow and snow melting features. To search the behavior of the ion at snow-melting, the thermal analyses of the melting water of snow were done with Differential Scanning Calorimetry to analyses of the melting temperature and melting energy of uniting water and free water with different ion species and ion concentrations. The difference of flow out speed between different ion species can be seen, but also between different snows. It seems to be related to different ions and ion concentrations.Precipitation in winter was classified into three forms of hailstone, snow and rain, to examine the charact … More eristic of ion concentrations by the difference of the form of precipitation. Each concentration of the major ions showed some different features.To examine an atmospheric chemistry system in the background of pH value in precipitation, measurements of hydrogen peroxide (H_2O_2) concentration in precipitation were carried out. H_2O_2 has a strong correlation with OH-radical that becomes the leading part of the oxidation of SO_2 and NO_2 in atmosphere. This research accomplishment was delayed because the severe earthquake attacked Chuetsu region, Niigata Prefecture, in October, 2004. However, the measurement of H_2O_2 concentration will become possible soon and some interesting results are being obtained. The H_2O_2 concentration in precipitation of winter at Nagaoka City indicated a high value in daytime. Moreover, a tendency that the H_2O_2 concentration decreases was seen as precipitation increased. Examining the relation between SO_4^<2-> and NO_3^- -H_2O_2 concentration, an especially clear correlation was not obtained though a constant tendency was seen. Less