Activated carbon is proposed as a new use of wastepaper as an alternative to using it to make recycled paper. Waste kraft bag is considered to be a suitable raw material for activated carbon because of it has a low ash content. Small pellets of wastepaper that were extruded from a continuous kneader were carbonized in a nitrogen atmosphere and activated using carbon dioxide. The Brunauer-Emmett-Teller (BET) specific surface area of activated carbon prepared from waste kraft bag was 1,285 m²/g, which is higher than that of commercial activated carbons. The activated carbon prepared from wastepaper has a well-developed porous structure, particularly in the mesopore range. As a result, activated carbon with an iodine adsorption capacity of 1,400 mg/g was obtained from waste kraft bag. In this study, the amount of bisphenol A (BPA) that was adsorbed was determined to investigate adsorbability of activated carbon derived from waste kraft bag. Adsorption measurements were performed on solutions with concentrations from 0.1 μg/l to 100 mg/l. The activated carbon from waste kraft bag had higher BPA adsorbabilities than commercial activated carbons over a wide range of concentrations.

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In a previous paper, the dyeability of leveling acid dyes for shrink-proofed wool fabrics treated with permonosulfate (PMS) and a keratinase was discussed on the basis of the dyeing rate and sorption isotherms. In the present study, ozone was employed instead of PMS for the pretreatment of wool fabrics to achieve a zero-AOX shrink-resist process. Three kinds of leveling acid dyes, which have one, two, or three sulfonate groups, were used. The dyeing rate and sorption isotherms were determined to elucidate the effects of the dye structure and the treatment of the wool fibers. The apparent diffusion coefficients were considerably diminished by the ozone treatment, but they were restored by the subsequent treatment with the enzyme. The sorption isotherms were analyzed using dual sorption mechanism to evaluate the three sorption parameters, which are the number of binding site, S, the intrinsic binding constant for the Langmuir type sorption, K_L, and the partition coefficient, K_P. The equilibrium dye uptake and the S values were almost unchanged by the ozone treatment. The K_L values for the ozone-treated fibers were slightly decreased compared to those of the untreated ones. The ESCA spectra showed the presence of cystine monoxide (-SO-S-), cystine dioxide (-SO₂-S-), and cysteic acid (-SO₃^-) after the treatment with ozone. If cysteic acid was generated on the fiber surface and also cell membrane complex (CMC) after the ozone treatment, the dyeing behavior should be influenced by the repulsion between the negatively charged cysteic acid and negatively charged acid dyes. The decreased dyeing rate and the unchanged dye uptake after the ozone treatment suggest that the action of ozone is limited onto the fiber surface and CMC, and does not affect the bulk structure of the fibers.

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The wool fabrics were treated by pulse corona discharge, followed by a keratinase to obtain shrink-proofed wool fabrics. The effects of the dual treatment on surface modification and dyeability for three kinds of leveling acid dyes with one, two, or three sulfonate groups in the structure were investigated. Although the physical surface was almost unchanged by the pulse corona discharge judging from the SEM observation, the ESCA analyses showed that the components of C and S atoms were greatly changed by the discharge. From the surface chemical composition, it is likely that the lipid layer of wool was partly removed and the remaining one on the surface was oxidized to give -C-O-,-C=O and -COO- residues. Furthermore, the presence of cystine monoxide (-SO-S-), cystine dioxide (-SO₂-S-), and cysteic acid (-SO₃^-) was confirmed after the discharge. The dyeing rate was increased considerably by the pulse corona discharge/enzyme treatment, but the equilibrium dye uptake was unchanged. The sorption isotherms obtained were analyzed using dual sorption mechanism consisted of the Langmuir and partition type sorption, and three sorption parameters, which are the number of binding site, S, the intrinsic binding constant for the Langmuir type sorption, K_L, and the partition coefficient, K_P are discussed.

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The computer program based on our mathematical model of the plain knitting process can predicted the loop length and the course length, the yarn tensions in the plain knitting zone, the robbing back length on the course or the loop, RB%, the maximum yarn tension value and position. The effects of the depth of stitch draw, the cam angle, the step length of cam and the input tension on the course length or the loop length, the yarn tensions in the plain knitting zone, the robbing back length on the course or the loop, RB%, the maximum yarn tension value and position are analyzed theoretical. The results obtained are as follows. 1) The course length increases with the increase of the depth of stitch draw, the cam angle and the step length of cam, but decreases with the increase of the input tension. 2) The robbing back length and RB% increase with the increase of the depth of stitch draw and the input tension, but decreases with the increase of the cam angle and the step length of cam. 3) The maximum tension increases with the increase of the depth of stitch draw, the step length of cam and the input tension, but decreases with the increase of the cam angle.

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The self-assembling behavior for the oligopeptides obtained from the dissolution of feather keratins via the alkaline hydrolysis process was investigated. The entities generated from the aqueous solution of oligopeptides showed a dendrite-like and non-birefringent structure. To enhance the molecular orientation for the oligopeptides in the assembling process, the electrospinning was applied. The as-spun fibers showed birefringent structure. However, no crystal diffraction was recognized in the selected-area electron diffraction analysis. To modify the crystallizing property of the oligopeptides, the superheated water treatment was conducted and the cystine and/or cysteine residues were completely destroyed. Then the entities from the aqueous solution of the treated oligopeptides became crystalline. However the crystal growth stopped up to its diameter of ∼40 μm.

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