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Partially deacetylated chitins with different degrees of deacetylation (DD) were prepared by alkaline treatment under homogeneous conditions, and the effect of DD on their solubility was discussed in terms of crystal structure and mode of hydrogen bonding. With an increase in the treatment time, the DD of chitin increased proportionally. The chitin became soluble in dilute acetic acid at the DD of ca. 28% or over and soluble in water at the DD of ca. 49%. The solubility of the partially deacetylated chitins had a close relationship with their crystal structure, crystallinity, and crystal imperfection as well as the glucosamine content. The wide-angle X-ray diffractometry (WAXD) revealed that the chitin with ca. 28% DD retained the crystal structure of alpha-chitin with significantly reduced crystallinity and perfection of the crystallites. The water-soluble chitin of ca. 49% DD had a new crystal structure similar to that of beta-chitin rather than either alpha-chitin or chitosan, suggesting that the homogeneous deacetylation transformed the crystal structure of chitin from the alpha to the beta form. Some hydrogen bonds existing in raw alpha-chitin were found to be missing at a DD of ca. 49%.

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The distribution of tritium in water vapour and precipitation with discharge of tritiated water vapour and meteorological factors was studied around the Wolsung nuclear power plant (NPP) site during the period 2004-2008. The tritium concentrations in atmospheric water vapour and precipitation had a temporal variation with relatively high values in the early summer. Spatial distribution of tritium concentrations was affected by various factors such as distance from the NPP site, wind direction, tritium discharge into the atmosphere and atmospheric dispersion factor. The annual mean concentrations of atmospheric HTO and precipitation were correlated with the amount of gaseous tritium released from the Wolsung NPP. The tritium concentrations in precipitation decrease exponentially with an increase of the distance from the Wolsung NPP site.

The partially deacetylated chitin with degree of deacetylation of ∼28%, fully soluble in dilute acetic acid, was prepared by alkaline treatment under homogeneous conditions and then blended with poly(vinyl alcohol) (PVA) using aqueous acetic acid solution as a cosolvent. The miscibility and intermolecular interaction between chitin and PVA were investigated using differential calorimetry. When chitin was blended with PVA up to 50%, the melting temperature (T m ) and heat of fusion ( H f ) of PVA were depressed gradually. The interaction energy density (B) and the interaction parameter (χ 12 ) estimated from the depression of melting temperature were −10.13 J/cm 3 and −0.33 (at 502 K), respectively. The negative value of χ 12 indicates that chitin and PVA are miscible. With increasing weight fraction of chitin in blends, there were large and systematic decreases in the crystallization temperature (T c ) and the heat of crystallization ( H c ) of PVA. The glass transition temperature (T g ) of PVA tended to shift to higher temperatures, with increasing weight fraction of chitin up to 40% in the blends. There was a broadening of the width of the transition.