Thermally modified bamboo-eggshell adsorbent for phosphate recovery and its sustainable application as fertilizer2023 · 記述言語： 英語 掲載種別： 研究論文（学術雑誌） 出版者・発行元： Environmental Research Phosphate recovery from wastewater using readily available biowaste-based adsorbents is beneficial for both eutrophication control and waste management. Bamboo char has a high-density porous structure and eggshell contains CaCO3 with high affinity for phosphate. The combination of calcined bamboo and eggshell is a potential adsorbent for P recovery that has not been tested previously. Because bamboo char and eggshell both are popular for soil amendment, a P-loaded bamboo and eggshell composite is a promising fertilizer for long-term soil improvement. In this work, the feasibility of calcined bamboo and eggshell (BE) for P recovery and its use as fertilizer were investigated. The adsorption capacity and mechanism were examined using adsorption kinetic, isotherm, and thermodynamic analysis. The kinetic study showed that the experimental data sets were fitted best by a pseudo second-order model, indicating chemisorption. The Langmuir isotherm model estimated maximum adsorption capacities of 95.14 and 98.40 mg/g for BE 1:1 and 2:1 adsorbent. Monolayer adsorption occurred on a homogenous surface. The adsorption reaction was non-spontaneous at 298 K and exothermic for the BE 1:1 and 2:1 adsorbent, and the calculated Langmuir separation factor indicated favorable conditions for P adsorption. The desorption study showed lower P desorption capacity in water than in neutral ammonium citrate. P-loaded eggshell-modified bamboo char was an effective slow-release fertilizer for Japanese mustard spinach cultivation, which is a sustainable and environment friendly use of P-loaded materials. DOI： 10.1016/j.envres.2023.115992 Scopus その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85154551207&origin=inward
Relationship between Dynamic Viscoelasticity and Amorphous Structural Changes Associated with Enthalpy Relaxation in Polystyrene Injection Moldings2022 · 記述言語： 日本語 掲載種別： 研究論文（学術雑誌） 出版者・発行元： Nihon Reoroji Gakkaishi In this study, we investigated the relationship between the amorphous structural changes associated with enthalpy relaxation and the Heat distortion temperature (HDT) in polystyrene injection moldings. It was clarified that the longer heat treatment time, the more enthalpy relaxation progressed. Also, an extrapolation glass transition temperature (Tig) increased by heat treatment. In addition, long-time heat treatment caused the high-temperature shift of the storage modulus (E') decrease temperature near glass transition temperature (Tg). Since the increase in Tig and the high-temperature shift of E' decrease temperature correlated with the enthalpy relaxation, they can be closely related to the enthalpy relaxation. Thus, we considered that the segment motion of polymer chain was suppressed as the enthalpy relaxation progressed. At long-term heat treatment, the enthalpy relaxation and the HDT were correlated. Furthermore, density increased by the heat treatment, and the increase in density also correlated with the progress of the enthalpy relaxation. Therefore, we considered that the polymer chains densely packed along with the enthalpy relaxation. As the result of polymer chains being densely packed, the segment motion of polymer chains near Tg can be suppressed and the HDT increased. DOI： 10.1678/rheology.50.181 Scopus その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85130399717&origin=inward
Effects of Copolymer Composition on Phase Transition Behavior and Mobility of Mesogenic Group for Side-Chain Liquid Crystalline-Amorphous Random Copolymers2022 · 記述言語： 日本語 掲載種別： 研究論文（学術雑誌） 出版者・発行元： Nihon Reoroji Gakkaishi Liquid crystalline (LC) phase behavior, higer-order structure, and mobility of mesogenic groups were investigated by using DSC, polarizing optical microscopy, small-angle X-ray scattering (SAXS), wide-angle X-ray diffraction (WAXD) and dielectric relaxation spectroscopy (DRS) for random copolymers composed of cyanobiphenyl-based side-chain LC and the amorphous components with various compositions. LC phase behavior of the copolymers was systematically changed depending on the mole fraction of the LC component, fLC11. When fLC11 > 0.75, incorporation of small fraction of the amorphous component resulted in slightly highered LC order and almost unchanged LC-isotropic transition temperature, Tiso. This may be because the copolymerization of the amorphous component canceled the inherent frustration in the LC homopolymer, which comes from the dissidence between lateral distance of adjacent nearest mesogenic groups in the smectic LC phase and that of the side-chains on mainchain. According to the DRS measurements, incorporation of the amorphous component also accelerated the molecular mobility of the mesogenic groups, which may be also related to the relaxation of the internal conformational frustration because of the dissidence. DOI： 10.1678/rheology.50.189 Scopus その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85130366850&origin=inward
