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1.
To enhance chemical stability and suppress of aggregation of magnetite nanoparticles (MNPs), which are used as a support for thermoresponsive copolymer immobilization, silica coating of the MNPs is applied via the electrooxidation method. Although the resulting silica coated-MNPs also formed aggregates, the size distribution of the aggregate shifted to smaller size range. Because of that, the surface area available for copolymer immobilization increased approximately 6.7 times at maximum as compared with that of the uncoated MNPs. It contributed to the increase of the amount of the immobilized copolymer on the silica-coated MNPs, which is approximately four times larger than that on the uncoated MNPs. Fe3O4 dissolution test confirmed enhancement of chemical stability of MNPs. The thermoresponsive copolymer immobilized on the silica-coated MNPs shows the ability to recycle Cu(II) ion from Cu(II) containing solution by changing temperature with significantly shorter time than those in other thermoresponsive adsorbents in gel form. 相似文献
2.
Akiko Suzuki Mina Minamide Chihiro Iwaya Kenichi Ogata Junichi Iwata 《International journal of molecular sciences》2020,21(23)
Carbohydrates, fats, and proteins are the underlying energy sources for animals and are catabolized through specific biochemical cascades involving numerous enzymes. The catabolites and metabolites in these metabolic pathways are crucial for many cellular functions; therefore, an imbalance and/or dysregulation of these pathways causes cellular dysfunction, resulting in various metabolic diseases. Bone, a highly mineralized organ that serves as a skeleton of the body, undergoes continuous active turnover, which is required for the maintenance of healthy bony components through the deposition and resorption of bone matrix and minerals. This highly coordinated event is regulated throughout life by bone cells such as osteoblasts, osteoclasts, and osteocytes, and requires synchronized activities from different metabolic pathways. Here, we aim to provide a comprehensive review of the cellular metabolism involved in bone development and homeostasis, as revealed by mouse genetic studies. 相似文献
3.
The effect of fatty acid structure of polyethyleneimine (PEI)-fatty acid complex, which was designed as a polymer dispersant for multi-component non-aqueous slurries, on the overall processing chain of Si3N4 ceramics involving slurry stabilization, spray drying, compaction, and liquid sintering was investigated using PEI-oleic acid (PEI-OA) and PEI-isostearic (PEI-ISA) complexes. Si3N4-Y2O3-Al2O3-AlN-TiO2/toluene slurries were selected as a real model for Si3N4-based multicomponent slurries. It was observed that both PEI-OA and PEI-ISA can stabilize Si3N4-Y2O3-Al2O3-AlN-TiO2/toluene slurries; however, the PEI-ISA system tended to have slightly higher slurry viscosity, which was suspected to be due to the interactions between protruded PEI segments among short ISA chains. The spray-dried granules from PEI-ISA-stabilized slurry were observed to have filled structures with higher surface roughness whereas those prepared from PEI-OA-stabilized slurry were observed to have hollow-structured granules. The granules prepared from PEI-OA slurry had improved flow and compaction properties with higher relative density of green compacts compared with those prepared from PEI-ISA-stabilized slurry, whereas the relative density and microstructural homogeneity of S3N4 ceramics sintered at 1600?°C for 2?h were observed to be higher for the PEI-ISA system. It is suspected that PEI-OA effectively improved the dispersion stability of multicomponent slurries and flow/compaction properties of granules; however, the inhomogeneous microstructures of green compacts induced by the hollow-structured granules had an adverse effect on the sintering of Si3N4 ceramics. 相似文献
4.
Hideo Yamauchi Junichi Ikejiri Fumio Sato Hiroyuki Oshita Tsuyoshi Honma Takayuki Komatsu 《Journal of the American Ceramic Society》2019,102(11):6658-6667
In recent years, the expansion of demand for lithium ion batteries has resulted in soaring prices of the constituent resources. From the viewpoint of safety, studies on all-solid-state batteries are actively being carried out. In this study, we succeeded in driving all-solid-state batteries derived from nontoxic oxide glasses at room temperature without requiring scarce resources such as lithium and cobalt. The main structure of the ceramic batteries with a simple structure in which Na2FeP2O7 crystallized glass and β″-alumina solid solution are joined by pressureless cofiring at 550°C. During the crystallization of Na2O-Fe2O3-P2O5 glass, fusion with the β″-alumina solid solution is achieved. Reversible charge and discharge of 80 mAh/g were achieved at room temperature. It is not necessary to apply pressure during cell preparation or the use of the batteries. Furthermore, the strong junction at the cathode and electrolyte interface does not peel off during charge and discharge over a long period of 623 cycles. Ex situ X-ray photoelectron spectroscopy revealed partial Fe4+ induction and a reversible charge and discharge reaction even after overcharging to 9 V. It was demonstrated that Na2FeP2O7 is very stable against overcharging to 9 V. 相似文献
5.
6.
Nosal Briana M. Sakaki Junichi R. Kim Dae-Ok Chun Ock K. 《Food science and biotechnology》2022,31(8):1081-1088
Food Science and Biotechnology - Although coffee has been reported as a major contributor to antioxidants in the diet, there are limited studies assessing how brewing methods and types of coffee... 相似文献
7.
Tsukaho Yahagi Daisuke Kawai Takuma Takahashi Motoyuki Iijima Junichi Tatami 《Journal of the American Ceramic Society》2022,105(3):2046-2057
Si3N4 ceramics with excellent mechanical properties are used for heat dissipation substrates and so on. In order to improve their reliability and expand their application fields, it is desirable to understand and control the electrical properties of Si3N4 ceramics. In this study, the electrical resistivity of Si3N4 ceramics with Yb2O3 additive was investigated by applying various voltages at temperatures ranging from 25°C to 300°C. When Yb2O3 was added as a sintering aid to Si3N4 ceramics, a crystalline J-phase (Yb4Si2O7N2) was formed and their electrical resistivity was significantly lower than that of Y2O3 additive. The electrical resistivity of the Yb2O3-added ceramics decreased with an increase in temperature and applied voltage. Yb existed in multiple valence states, Yb2+ and Yb3+, in the Si3N4 ceramics and the decrease in the electrical resistivity can be attributed hopping conduction through the J-phase. The J-phase in the Si3N4 ceramics was observed to be continuous, and percolation analysis suggested that the J-phase formed an infinite cluster. Therefore, the decrease in the electrical resistivity of the Yb2O3-added Si3N4 ceramics was found mainly to result from the formation of an infinite cluster of J-phase, which exhibits hopping conduction. 相似文献
8.
Mizuki Tsuta Yasuhiko Sasaki Ikuo Takeuchi Hideki Nakamoto Jun Ishikawa Susumu Kawasaki Junichi Sugiyama Kaori Fujita Masatoshi Yoshimura Mario Shibata Mito Kokawa 《LWT》2014
Flow cytometry (FCM) and aerobic plate count (APC) by the culture method were performed on green tea samples spiked with Escherichia coli type strain NCTC9001 (ATCC11775) solutions of different concentrations. In FCM, fluorescence signals from multiple stained bacteria and other fluorophores are detected using detector channels, and recorded as events with a voltage at each channel. FCM data were analyzed in two ways: conventional and multivariate analysis. In the former, the number of events with voltages larger than the defined threshold values was regarded as the predicted APC. In the latter, voltage histograms of all channels were obtained and merged horizontally to serve as explanatory variables. Then a partial least squares regression (PLSR) model was built to predict APC from the histogram data. The coefficient of determination (R2) and the root mean square error (RMSE) between APC by the culture method and that predicted by conventional FCM were 0.916 and 1.08 cfu/ml2. The APC values predicted by the PLSR model and those measured were in good agreement with R2 of 0.982 and RMSE of 0.417 cfu/ml, which verified the potential of the proposed method for improving APC prediction accuracy by FCM. 相似文献
9.
Masatoshi Hasegawa Mari Fujii Junichi Ishii Shinya Yamaguchi Eiichiro Takezawa Takashi Kagayama Atsushi Ishikawa 《Polymer》2014
A novel cycloaliphatic monomer for polyimides (PI), 1S,2S,4R,5R-cyclohexanetetracarboxylic dianhydride (H′-PMDA) is proposed in this work. H′-PMDA shows high polymerizability with various diamines in contrast to its isomer, i.e., conventional hydrogenated pyromellitic dianhydride (H-PMDA) and leads to highly flexible and colorless PI films with very high Tg's. In particular, the combinations with rigid structures of diamines give rise to PIs with significantly decreased coefficients of thermal expansion (CTE) owing to high extents of in-plane chain orientation induced by thermal imidization, whereas the H-PMDA-based counterparts do not. The decreased CTE reflects structural rigidity/linearity of the H′-PMDA-based diimide units as supported by liquid crystallinity observed in the corresponding model compound. Solution casting of a chemically imidized PI derived from H′-PMDA and 2,2′-bis(trifluoromethyl)benzidine (TFMB) results in a lower CTE than that of the thermally imidized counterpart, suggesting the presence of a self-orientation phenomenon during solvent evaporation. The mechanism is proposed in this work. H′-PMDA/TFMB and its copolymer systems can be useful as plastic substrates in image display devices and/or novel coating-type optical compensation films. 相似文献
10.
Junko Matsuki Tomoko Sasaki Koichi Yoza Junichi Sugiyama Hideo Maeda Ken Tokuyasu 《Journal of Applied Glycoscience》2019,66(4):113
Rice-gel prepared by the following three steps: rice grain cooking, shearing of the cooked rice, and cooling for gel formation, is expected as a novel food ingredient for modification of various food products such as bread and noodles. To meet the demand for high-throughput systems for research and developments on the new rice gels, herein we established a mini-cooking system for preparation of rice gel samples from grains using a small-scale viscosity analyzer (Rapid Visco Analyzer; RVA). Polished rice grains (4 g) were cooked with 22 mL of water in a canister, and the paddle equipped in the canister was rotated at 2,000 rpm for 30 min (80 °C was used as a representative) to shear the cooked rice. The sheared paste was cooled to 10 °C at 160 rpm, and the initial gelation property was evaluated by viscosity analysis within the RVA. Alternatively, the sheared paste was transferred to an acrylic mold and kept at 4 °C for 0, 1, 3, and 5 days for determination of the hardness with a compression test. Compressive forces required to penetrate 20 % thickness for three tested rice cultivars were measured, and the trend of the value shifts during preservation is similar to the corresponding trend obtained in 300-g grain scale laboratory tests, whereas the individual values were halved in the former. This small cooking method could offer a useful assay system for a rapid evaluation in the breeding programs and in the high-throughput screening of additives for the modification of properties. 相似文献