Carbonization behavior of the mulberry silk, the tussah silk and the component amino acids have been investigated. From the silk, non-graphitizing carbon could be obtained with a yield of 30%, which was much higher than the value measured for the cellulose-based carbon. The tussah silk showed a higher thermolysis temperature than the mulberry silk, while there was no marked difference in the yield of carbon between these silks. At early stage of carbonization of the silk, amide bonding was dissociated at temperatures higher than 300oC, and the amorphous sericin and fibroin were liquefied. The degummed crystalline fibroin fiber, however, was not liquefied during carbonization. The activated carbon from mulberry silk did not show adsorption of methylene blue (MB), while that from tussah silk showed adsorption of MB of about 60 mg/g.

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A sedimentation experiment was used as a simple method to evaluate the PFI mill beating degree of wood pulp fibers. The sedimentation volume decayed exponentially with elapsed time. The sedimentation rate, k, changed with the beating degree, though the equilibrium sedimentation volume remained relatively constant. The rate k decreased with the increasing concentration, c, and the beating degree; and moreover, k-1 was proportional to c. This result suggests that k-1c-1 can be a unique factor for the beating degree. The factor expresses the beating degree well and can also tell us that the single fiber properties are more important than inter-fiber interactions during the sedimentation process of the CSF measurement.

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A series of HIV vaccine models based on lactose-bound poly(lysine) scaffolds was synthesized. A spherical poly(lysine) dendrimer was prepared to bind lactose at the peripheral through reductive amination. Lactose-poly(lysine) dendrimers with the degree of substitution (DS) varying from 5 to 19 were obtained by controlling the feeding ratio of lactose to the poly(lysine) dendrimer. Three succinylated compounds such as succinyl monobenzylate, ethyl-phenylalanyl succinylamide and succinyl-L-alanyl-L-prolyl-L-alanine p-nitroanilide which were regarded as antigen peptide models were bound to the lactose-poly(lysine) dendrimer through esterification between the carboxyl group of the succinyl moiety and the 6-OH group of the lactose residue. The DS of resulting vaccine models was investigated by NMR spectra analyses.

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A novel conservation treatment for archaeological waterlogged woods has been developed using duck feather keratin hydrolysate prepared by degrading and dissolving waste duck feather and down with 1N NaOH at 70oC for 3h. The treatment with increasing a concentration of duck feather keratin hydrolysate in a treatment bath is effective to suppress the shrinkage at drying and to retain the dimension of archaeological waterlogged woods. A slight expansion, however, can be observed for the woods treated with the keratin hydrolysate solution of 40%. In addition, the treatment is also effective for the reinforcement of the cell walls of woods. The molecular weight of duck feather keratin hydrolysate ranges from 1 kDa to 5.7 kDa, and not a small amount of low molecular hydrolysate smaller than 1 kDa is also contained. The enhancement in shrinkproof property and reinforcement of cell walls seems to be brought about by the keratin hydrolysate settled in the cell walls. Furthermore, the treatment does not affect the hues of woods.

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The method to objectively evaluate and to predict the fabric wrinkle resistance using the neural network was proposed in this paper. The fabric wrinkle resistance could be predicted by use of their textural feature and mechanical parameters. The correlation coefficient between the predicted value and practical wrinkle grade was as high as 0.9. The results showed that the wrinkle resistance of cotton fabrics not only could successfully be predicted using the neural network model that has been trained, but also could precisely be done using the one that has not been learned.

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