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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
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Hubby Izzuddin Shigenari Hayashi Suzue Yoneda Takashi Kogin Eiji Ishikawa Manabu Noguchi 《工业材料与腐蚀》2020,71(9):1488-1499
The effect of Mo on the corrosion behavior of Ni20Cr–xMo alloys in an oxidizing chlorine-containing atmosphere using air mixed with the salt-vapor mixture of NaCl–KCl–CaCl2 at 570°C was investigated. The results revealed that the corrosion performance of the Ni20Cr alloys in the oxidizing chlorine atmosphere was improved by Mo addition of up to 3 wt%. The Mo-free alloy formed a potassium chromate during corrosion as a result of the reaction between the Cr2O3 scale and KCl vapor. The chromate formation increased the chlorine potential at the scale surface and induced the breakdown of the protective Cr2O3 scale, resulting in internal chromium chloride precipitates and a Cr-depleted zone. In contrast, the presence of Mo resulted in the formation of a NiO scale, which did not react with the salt vapors and, therefore, prevented the formation of chromates. The beneficial effect of Mo on the high-temperature chlorination of Ni–Cr alloys in salt-vapor-containing atmospheres was ascribed to the suppression of chlorine generation due to NiO scale formation. 相似文献
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Computational Visual Media - Quantitatively evaluating the psychological and perceptual effects of objects is an important issue, but is difficult. In cognitive studies, the psychological potential... 相似文献
5.
Heme can be removed from a number of native hemoproteins, thus forming corresponding apoproteins, each of which provides a site for binding of a metal complex. In one example, myoglobin, an O2 storage protein, can be reconstituted with iron porphycene to dramatically enhance the O2 affinity. Although it is known that myoglobin has poor enzymatic activity, the insertion of iron corrole or iron porphycene into apomyoglobin increases its H2O2-dependent peroxidase/peroxygenase activities. Furthermore, reconstitution with manganese porphycene promotes hydroxylation of an inert C H bond. It is also of interest to insert a non-porphyrinoid complex into an apoprotein. A cavity of apocytochrome c has been found to bind a diiron carbonyl complex, serving as a functional model of diiron hydrogenase. Aponitrobindin has a rigid β-barrel structure that provides an excellent cavity for covalently anchoring a metal complex. A rhodium complex embedded in the cavity of genetically modified nitrobindin has been found to promote stereoselective polymerization of phenylacetylene. 相似文献
6.
Kazuma Oikawa Kei Toyota Shigeaki Sakatani Yamato Hayashi Hirotsugu Takizawa 《Ceramics International》2019,45(4):4201-4207
In this study, new rGO-silica xerogel nanocomposites (SX-rGO) and its glass fiber reinforced composites (GFR-SX-rGO) were prepared, and its microstructure and thermal properties were evaluated. The raw material was a mixed dispersion prepared by adding 0.01–2.5?wt% of reduced graphene oxide (rGO) to waterglass (6% SiO2). A hydrogel was prepared via sol-gel reaction of this raw material, which was then immersed in hydrochloric acid, hydrophobized in a siloxane/2-propanol reaction system, and then dried at ambient pressure to obtain a hydrophobic carbon-silica xerogel composite. The obtained samples were characterized by N2 physisorption (at 77?K), solid 29Si Magic angle spinning nuclear magnetic resonance spectroscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, differential scanning calorimetry, thermogravimetric analysis, hydrophobicity, and thermal conductivity. It was found that as the amount of rGO was increased, the specific surface area of the nanocomposite decreased by ~25% from 535 to 403?cm2/g, and the average pore size and pore volume were almost halved. The thermal decomposition temperature of the SX-rGO was increased markedly by the addition of rGO. Moreover, the GFR-SX-rGO-0.5 showed low density (0.208?g/cm3), high contact angle (146°) and low thermal conductivity (0.0199?W/mK). 相似文献
7.
Latifa Seniorita Eiji Minami Yoshiteru Yazawa Hitoshi Hayashi Shiro Saka 《Journal of the American Oil Chemists' Society》2019,96(9):979-987
Monoacylglycerols (MAG) are impurities present in biodiesel as a result of incomplete reactions. MAG often solidify in biodiesel even at room temperature because of their high melting points. This worsens the cold-flow properties such as the cloud point and pour point. We hypothesized that several types of MAG solidify simultaneously; therefore, we performed differential scanning calorimetry of binary mixtures of MAG to elucidate their interactions during solidification. Three thermodynamic formulas were then applied to the experimental results: (1) non-solid-solution, (2) solid-solution, and (3) compound formation models. Binary mixtures of MAG showed complicated liquidus curves with multiple upward convex shapes, with which only the compound formation model fitted well. This model was applied to multicomponent mixtures that consisted of MAG and fatty acid methyl esters (FAME) as surrogate biodiesel fuels. We confirmed that the model still worked well. The results show that the compound formation model has good potential for predicting the cold-flow properties of biodiesel. 相似文献
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Yuka Tarui Takumi Chinen Dr. Yoko Nagumo Dr. Takayuki Motoyama Dr. Toshiaki Hayashi Dr. Hiroshi Hirota Dr. Makoto Muroi Yasuyuki Ishii Hisae Kondo Prof. Dr. Hiroyuki Osada Prof. Dr. Takeo Usui 《Chembiochem : a European journal of chemical biology》2014,15(7):934-938
Terpendole E is first natural product found to inhibit mitotic kinesin Eg5, but its inhibitory mechanism remains to be revealed. Here, we report the effects of terpendole E and 11ketopaspaline (a new natural terpendole E analogue) on the Eg5–microtubule interaction and in several Eg5 mutants. 11‐Ketopaspaline is a shunt product from terpendole E, and it shows potent inhibitory activity against the microtubule‐stimulated ATPase activity of Eg5. Unlike other Eg5 inhibitors, such as S‐trityl‐L ‐cysteine (STLC) and GSK‐1, both terpendole E and 11‐ketopaspaline only partially inhibited Eg5–microtubule interaction. Furthermore, terpendole E and 11‐ketopaspaline inhibited several Eg5 mutants that are resistant to STLC (Eg5D130A, Eg5L214A) or GSK‐1 (Eg5I299F, Eg5A356T), but with the same extent of inhibition against wild‐type Eg5. Because Eg5D130A and Eg5L214A show cross‐resistance to most known Eg5 inhibitors, which bind the L5 loop, these results suggest that terpendole E and its analogues have a different binding site and/or inhibitory mechanism to those for L5 loop‐binding type Eg5 inhibitors. 相似文献
10.
Takatoshi Shindo Hideki Motoyama Toru Miki Mikihisa Saito Akiyori Matsueda Noriyasu Honma Tomohito Hida Kazuo Shinjo Kiyotaka Hayashi Hayato Awazu Katsuhisa Makabe Masato Fujikawa Satoshi Kurihara Masashi Sato 《IEEJ Transactions on Electrical and Electronic Engineering》2016,11(Z2):S28-S33
Nine electric power companies in Japan have been collecting lightning data with lightning location systems. Five years of the lightning data (2009–2013) are summarized and analyzed in this paper. The recent annual number of lightning flashes of which the current is more than 10 kA in Japan is around 1 million. The variations of lightning occurrence characteristics by areas, seasons, and so on, are clarified. Meteorological conditions that may affect lightning occurrence are also discussed. Furthermore, we show that there is a clear correlation between the number of lightning strikes and the outage rate of transmission lines. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献