In hair‐bleaching treatment, it is well‐known that disulfide bond in keratin fiber is oxidatively cleaved to generate cysteic acid. In the present study, we examined cysteic acid generation behavior in human hair fiber based on infrared spectroscopy. It was suggested from a result of attenuated total reflection (ATR) method that the amount of cysteic acid increases linearly with square root of bleaching time, and the cysteic acid generation in the hair is a diffusion‐controlled reaction. As the analysis part of the hair by the ATR method is cuticles, this diffusion‐controlled behavior seems to occur mainly in the A‐layer and exocuticle with higher disulfide crosslink density and slower diffusion rate of hydrogen peroxide. In addition, it was found out that cysteic acid generation in cortex is also diffusion‐controlled because the amount of cysteic acid obtained by KBr method increases linearly with square root of bleaching time similarly to the results of ATR method. In an IR microscopic measurement using synchrotron radiation source, it was revealed that the amount of cysteic acid generated by bleaching is even within the cortex. From this result, it was suggested that the diffusion‐controlled behavior for cysteic acid generation in the cortex is caused by controlling the diffusion of hydrogen peroxide from cell membrane complex into cortical cell.

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Kinetic analysis was applied to investigate the alkaline hydrolysis behavior of poly(ethylene terephthalate) (PET) fibers, e.g., two types of commercial fully oriented yarn (FOY), partially oriented yarn (POY), and high‐speed spun (HSS) fibers. The activation energies obtained from the Arrhenius plots using the topochemical hydrolysis reaction rate constants, i.e., the apparent hydrolysis erosion speed for each PET sample, were concentrated within the range of 62.4　-　69.5 kJmol^-1 without respect to their higher‐order structures. Therefore, it has been deduced that the reaction rate constant depends on the frequency factor, especially on the steric factor at constant temperature. As for the as‐spun HSS fibers with higher crystallinity and lower overall molecular orientation, their rate constants could be well described using the newly defined combined parameter, i.e. the apparent lamellar size normalized in terms of birefringence and crystallinity, which implies that the larger crystallite is more effective in the topochemical hydrolysis erosion of PET fibers while crystallinity and birefringence closely related to the cohesiveness of adjacent molecular chains work negatively. However, the combined parameter proposed could not describe the hydrolysis kinetics anymore after the as‐spun HSS fibers were annealed to enhance the packing of amorphous regions.

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In this study, pectin‐containing cellulose nanofibers (CNFs) were prepared from mandarin peel (MP), and the effect of pectin, which remained in purified cellulose after a purification treatment, on the aggregation of CNFs was investigated. Cellulose samples with different pectin concentrations were prepared by bleaching and a hydrothermal treatment with an acid solvent. Following the preparation of the different pectin‐containing cellulose samples, each cellulose sample was fibrillated by a high‐pressure homogenizer treatment. The morphological structures of CNF samples were observed using atomic force microscopy (AFM) and scanning electronic microscopy (SEM). The AFM images of the pectin‐containing CNFs showed that the pectin covered the surfaces of the CNFs and that the CNFs obtained from MP were finer than those obtained from wood cellulose. Further, the SEM images of the oven‐dried samples showed that the pectin‐containing CNFs were finer than the purified CNFs obtained from MP. Moreover, the oven‐dried pectin‐containing CNFs could be redispersed in water. This indicated that pectin has a potential to prevent the aggregation of CNFs. However, the addition of commercial pectin to a CNF suspension did not inhibit CNF aggregation. Although an interaction between the CNFs and pectin were confirmed in the case of the pectin‐containing CNFs prepared from MP, the commercial pectin did not interact with the purified CNFs. This CNF‐pectin interaction, which is based on their original structures, probably results in the pectin covering the surfaces of the CNFs. It is likely that this is the reason that the aggregation of the CNFs was inhibited.

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The efficient and effective decontamination technologies of radioactive ions from soil and water have been required after the Fukushima No. 1 nuclear power plant accident. In this study, we prepared a zeolite‐containing composite sheet for decontamination of radioactive ions present in water, and evaluated its cesium adsorption behavior in some model experiments. The composite sheet increased in the amount of adsorbed cesium ion with increasing cesium ion concentration in water in batch experiment. In filtration experiment, the maximum adsorption ratio of cesium ion reached 98%, depending on the number of plied sheets. Although the composite sheet had high adsorption ratios of both cesium and strontium ions dissolved in pure water, almost no adsorption of Ce⁺ or Sr²⁺ was observed when seawater was used in place of pure water. Moreover, once cesium‐adsorbed sheet released some amounts of cesium ion, when 0.1M NaOH or seawater was used in soaking treatment.

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hree kinds differently structural 3D woven fabrics with the basalt fiber filaments tows as warp and weft yarns were fabricated on common loom by reasonable design. And, three kinds differently structural 3D woven basalt fiber composite materials were obtained with vinyl ester resin as matrix materials and 3D woven fabrics as reinforced materials, by VARTM molding process (vacuum assisted resin transfer molding process). Then, the tensile and bending properties of three kinds differently structural 3D woven basalt fiber composite materials were tested throughout the universal testing machine. Results were shew that the 3D woven basalt fiber composite materials have excellent mechanical properties, but the different structures of 3D woven fabrics as reinforced materials exhibited a big difference on mechanical properties. The paper also applied the reasonable FEM(finite element modeling) models with ANSYS software to forecast the tensile and bending properties of 3D woven basalt fiber composite materials. The good agreements of the comparisons prove the validity of the FEM models.

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Cotton and wool fabrics were mordant‐dyed with C. I. Direct Red 28 (Congo red) and copper(II) sulfate. The removal behavior for pure ethanethiol or ammonia odor, and their mixed odor was examined by gas detection tube method. The relationship between the odor removal performances and the K/S spectra of sample fabrics before and after the removal experiments was investigated. Ammonia removal behavior for the mixed odor was almost the same for pure ammonia odor. On the other hand, ethanethiol removal ability was improved for mixed odor, which depended on the concentration ratio of ethanethiol and ammonia. Ammonia coordinated to the copper contributes to the improvement of ethanethiol removal.

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