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In this study, the formation of complexes between surfactants and the helical chains of amylopectins was confirmed. Nonionic surfactants with hydrophobic and hydrophilic groups of appropriate size and chemical structure enhanced the swelling and gelatinization processes of starch granules. Hydrophobic groups form complexes with the amylose and linear chains of amylopectin by becoming inserted into the hydrophobic inner area of the helical structures. The hydrophilic groups help the approach of the hydrophobic groups into the hydrated molecular chains and thus aid the formation of the complex. Among the anionic surfactants tested, SDS and sodium n‐decyl benzenesulfate caused maximum swelling and gelatinization peaks. The average length of the amylopectin exterior chains is almost the same as that of the hydrophobic chains of SDS (16.9 Å) and of sodium decyl benzenesulfate (18.2 Å). This suggests that these anionic surfactants form rigid complexes with the exterior of the amylopectin by fitting their hydrophobic chains to the hydrophobic inside of the helical structures of these short exterior chains. This process was clarified by NMR analysis and by a decrease in the complex with the addition of iodine. The hydrophobic alkyl chains of anionic and cationic surfactants fix to the edge of the starch molecular chains by forming inclusion complexes with the helical chains of the amylopectin. Cationic ions interact with the starch molecular chains, causing a negative charge that results in a more rapid and efficient swelling of the starch granules. A decrease in setback value occurs due to the inhibition of rearrangement among the starch molecular chains. With SDS, the complex molecular chains become more extensively developed through the repulsion effects of the anionic ions resulting in a larger swelling power and gelatinization peak.

The hydrogen exchange reaction of aniline with deuterium was investigated on supported nickel, cobalt and platinum. The following results were obtained: 1) At 150°C, the hydrogen of the amino group of aniline exchanges at a higher velocity than the hydrogen attached to the benzene ring. At temperatures as high as 300°C, the hydrogen exchange in the benzene ring increases further. 2) The suggested hydrogenation mechanism obtained from the results of the exchange reaction can not be correlated with that obtained from the kinetic study. 3) The catalytic activity for the exchange reaction in the benzene ring is in the order Pt>Co>Ni. 4) The basic oxide support seems to suppress the adsorption of the amino group. 5) The relationship between the adsorption state of the aniline on the catalyst surface and the various reaction products, such as cyclohexylamine, benzene and dicyclohexylamine, has been well established.

The hydrogenation of aniline in fluidized beds was studied.As a result of the experiments, the following conclusions were obtained:1) The reaction rate of the catalytic hydrogenation of respect to hydrogen. In the case of a large molar ratio of hydrogen to aniline , however, the reaction rate became zeroth-order with respect to aniline. 2) A good agreement was obtained between the conversion by the fluidized-bed experiment and the values calculated on the model of the contact-time distribution for low degrees of conversion. For high degrees of conversion, the deviation of the values calculated using this model from the experimental value was found to be about 10%. It was suggested that this model can well be applied to predicting the conversion for zeroth-order reaction within the limits of uncertainty given above.

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