A doubly-imaging fiber-lens (DIF) was fabricated by the photocopolymerization of methyl methacrylate with vinyl benzoate. The core and the outer portions of the DIF have the quadratic refractive-index distributions with different gradient-indexes from one another. The DIF forms two images different both in reduction rate and in image plane. Tracings of rays through DIF, assuming a meridional ray under paraxial condition, led to a simple and feasible method estimating the indexprofile of DIF on a basis of its lens function. The validity of this method was verified by the measurements in various conditions and the comparison with the index-profile determined interferometrically.

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An X-ray method for evaluating the α-form fraction of poly(γ-methyl glutamate) coexisting with the α-form crystal is described. The transformation from the α-helix structure to the β-pleated sheet structure in drawn specimens was found to be induced by annealing above a certain temperature in the presence of dichloroacetic acid. The transformation from the mixture of the α-and the β-forms to the β-form occurs slowly upon annealing at 423K and very rapidly at 453K for poly(γ-methyl glutamate) cast from a solution in dichloroacetic acid. The volume fraction of the β-form changed linearly with the logarithm of annealing time. The following factors were found to be essential for the completion of the α→β transformation: (1) the presence of dichloroacetic acid molecules which are thought to weaken the intramolecular hydrogen bond of the α-helix and facilitate the thermal molecular motion of the α-helix core, (2) a temperature high enough to provide the α-helix crystal with sufficient thermal energy, and (3) the presence of the β-form crystal as nuclei in the matrix of the α-crystal for the growth of the β-form crystal. The process conditions based on these factors were successfully applied for preparation of a high modulus fiber resembling to silk with respect to its modulus and crystal structure.

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In this study, the effects of dyes, which were dispersed in atactic polystyrene, on the enthalpy relaxation process was studied in order to investigate the mechanism of molecular motion at temperatures below T_g. Dyes used through were p-aminoazobenzene and C. I. Disperse Yellow 7. It is convenient to express the enthalpy changes that occur during isothermal annealing at a glassy state in terms of the excess enthalpy. The kinetics of the enthalpy relaxation was analyzed with the assumption of single relaxation time process. With an increase in the content of dyes, T_g of polymer decreased, the relaxation time of the enthalpy relaxation became long and the apparent activation energy increased. The longer the molecular length is, the lower T_g of polymer and the slower the rate of the enthalpy relaxation become.

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Structural studies of poly (β-benzyl L-aspartate) during casting process were performed in terms of the structure coacervated instantaneously from the solution. Poly (β-benzyl L-aspartate) was coacervated by adding a large amount of methanol to the solutions of concentration of 0.08 to 1.0. Differential scanning calorimetries of the samples were measured and classified into three types. All the thermograms exhibit the α-α transition, α-β transition and the exothermic decomposition peaks. The α-ω transition temperature of the coacervated samples changed stepwisely from 154, 140 to 120°C with the solution concentration. Transition temperature is 154°C for the concentration of 0.08 to 0.30, 140°C for 0.40 to 0.80 and 120°C for 1.0. First two transitions should include an exothermic change due to the rearrangement of α helix to a more ordered form in the process of heating, together with a change in the helix conformation. It can be seen from annealing effect of the coacervated samples that the transition of hexagonal array to tetragonal array is followed by a subsequent transition of α helix to ω helix.

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Two types of membranes of glutamic acid-methyl L-glutamate copolymers were obtained by the saponification of poly (γ-methyl L-glutamate) (PMLG) membranes in aqueous alcoholic systems. One is iM membrane and the other is E membrane. The iM membranes were obtained by the saponification in a mixture (2:2:1 in volume fraction) of methyl alcohol, isopropyl alcohol and water containing NaOH at various concentrations. The E membranes were obtained in a mixture (4:1 in volume fraction) of ethyl alcohol and NaOH aqueous solution. The sorption and the permeation behavior of these copolymer membranes depends on the glutamic acid content in these membranes, but not on the membrane preparing process. The membrane potential, however, depends on the membrane preparing method. That is, the absolute values of membrane potential of the E membranes were higher than those of the iM membranes. This difference could be ascribed to the difference in the surface character of the iM and of the E membranes.

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Quaternary ammonium and pyridinium salts were found to facilitate the reaction of carboxylic acids and amines promoted by triphenyl phosphite, and the reaction was successfully applied to the direct polycondensation reaction of dicarboxylic acids and diamines. Among the salts tested, tetraethylammonium chloride was most favorable. The reaction was extended to the direct polycondensation of amino acids in the presence of polyvinylpyrrolidone as a matrix: poly (β-alanine) with high molecular weight was obtained in high yields, but polymers from α-amino acids could not be isolated due to the difficulty in separating the polymers from the polymer matrix.

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The biodegradation of several dyes by starved intact cells and fresh intact cells of Pseudomonas pseudomallei 13NA has been studied. The degradation rate of the dyes by starved intact cells was faster than that of the dyes by fresh intact cells: starved cells degrade the dyes efficiently. It is considered that the degradation ability of the intact cells is dependent on nutritional circumstances and cell permeability of the dyes.

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The authors have examined how fluorescent brightening agents disappear in an urban river, the Nogawa, after discharge from domestic sources.
The behaviors of two typical fluorescent brightening agents (FBA-1 and FBA-2, see Table 1 for the chemical structures) for detergent in a river were proved to differ from each other. For FBA-1, the main disappearance factor was found to be photofading, on the other hand, for FBA-2, the main factor could not be specified. The transport ratios of the fluorescent brightening agents in the river were 87% for FBA-1 and 15% for FBA-2, respectively.
Mass balance of the fluorescent brightening agents built in detergent was estimated from these results.

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