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排序方式: 共有961条查询结果,搜索用时 31 毫秒
71.
Hideki Taguchi Katsuyuki Nakade Masashi Yosinaga Masaki Kato Ken Hirota 《Journal of the American Ceramic Society》2008,91(1):308-310
X-ray photoelectron spectroscopy was performed to elucidate the catalytic activity of CH4 oxidation on perovskite-type Ca(Mn1− x Ti x )O3−δ synthesized at 1173 K in a flow of oxygen from a gel with citric acid and ethylene glycol. The Mn ion content decreases and the ratio of the Mn3+ ion in the Mn ion increases with increases in x . Ca(Mn1− x Ti x )O3−δ has a high catalytic activity of CH4 oxidation at x =0.4. These results indicate that the catalytic activity strongly depends on the Mn3+ ion content of the surface. 相似文献
72.
Phase relations associated with the aluminum blast furnace: Aluminum oxycarbide melts and Al-C-X (X=Fe,Si) liquid alloys 总被引:2,自引:0,他引:2
Harumi Yokokawa Masao Fujishige Seiichi Ujiie Masayuki Dokiya 《Metallurgical and Materials Transactions B》1987,18(2):433-444
The thermodynamic properties and the phase relations were evaluated and estimated for the Al-O-C, Al-Si-C, and Al-Fe-C systems
which are important to understand the chemical behavior in an aluminum blast furnace. The mixing properties of binary liquid
alloys, including metal-carbon systems, were represented by the Redlich-Kister equation. The properties of liquid Al−C and
Si−C alloys were estimated so as to be consistent with their phase diagrams. The coefficients of Al−Fe and Fe−C liquids were
evaluated from reported values for activity and enthalpy. The extrapolation to the higher order systems was made by Maggianu's
method. The aluminum oxycarbide melt was represented by a subregular solution model. In the Al-O-C system, liquid alloy/oxycarbide
melt equilibria were calculated and compared with earlier experimental results and estimates. Attempts were made to clarify
the volatilization of aluminum oxycarbide melts, and also the carbidation of liquid aluminum alloys. An empirical correlation
between the first terms of the Redlich-Kister equation for the enthalpies and the excess entropies was discussed. 相似文献
73.
Makiyo Nishimura Chieko Fukuda Masatsune Murata Seiichi Homma 《Journal of the science of food and agriculture》2003,83(11):1156-1162
A PCR‐amplified genomic DNA fragment encoding Japanese pear (Pyrus pyrifolia) polyphenol oxidase (PPO) was cloned and sequenced. The DNA appears to encode a 66 kDa precursor protein consisting of a 56 kDa mature protein and a 9.5 kDa N‐terminal transit peptide. The amino acid sequence showed high homology with apple PPO. The PPO mainly existed as a soluble fraction in cells and was limitedly proteolysed, while the mature form (56 kDa) was detected in plastids. Immature fruits showing high browning potential had high PPO activity and a high level of phenolics, while mature fruits showing little browning had high PPO activity but a low level of phenolics. Copyright © 2003 Society of Chemical Industry 相似文献
74.
Improved polyhydroxybutyrate (PHB) production in transgenic tobacco by enhancing translation efficiency of bacterial PHB biosynthetic genes 总被引:1,自引:0,他引:1
Matsumoto K Morimoto K Gohda A Shimada H Taguchi S 《Journal of Bioscience and Bioengineering》2011,111(4):485-488
Polyhydroxybutyrate [P(3HB)] was produced in the transgenic tobacco harboring the genes encoding acetoacetyl-CoA reductase (PhaB) and polyhydroxyalkanoate synthase (PhaC) from Ralstonia eutropha (Cupriavidus necator) with optimized codon usage for expression in tobacco. P(3HB) contents in the transformants (0.2mg/g dry cell weight in average) harboring the codon-optimized phaB gene was twofold higher than the control transformants harboring the wild-type phaB gene. The immunodetection revealed an increased production of PhaB in leaves, indicating that the enhanced expression of PhaB was effective to increase P(3HB) production in tobacco. In contrast, codon-optimization of the phaC gene exhibited no apparent effect on P(3HB) production. This result suggests that the efficiency of PhaB-catalyzed reaction contributed to the flux toward P(3HB) biosynthesis in tobacco leaves. 相似文献
75.
Makoto Sasaki Motoki Inoue Yasuyuki Katada Yuuki Nishida Akiyoshi Taniguchi Sachiko Hiromoto Tetsushi Taguchi 《Science and Technology of Advanced Materials》2012,13(6)
Calcium phosphate was formed on nickel-free high-nitrogen stainless steel (HNS) by chemical solution deposition. The calcium phosphate deposition was enhanced by glutamic acid covalently immobilized on the surface of HNS with trisuccinimidyl citrate as a linker. X-ray diffraction patterns and Fourier transform infrared spectra showed that the material deposited on glutamic acid-immobilized HNS within 24 h was low-crystallinity calcium-deficient carbonate-containing hydroxyapatite (HAp). The biological activity of the resulting HAp-coated HNS was investigated by using a human osteoblast-like MG-63 cell culture. The HAp-coated HNS stimulated the alkaline-phosphate activity of the MG-63 culture after 7 days. Therefore, HAp-coated HNS is suitable for orthopedic devices and soft tissue adhesion materials. 相似文献
76.
77.
Seiichi Suzuki 《JOM Journal of the Minerals, Metals and Materials Society》2013,65(9):1254-1263
Features of transmission electron backscatter diffraction (EBSD) observation with a standard EBSD (s-EBSD) detector are surveyed in this study. Heavily deformed Al and 8Cr tempered martensite transmission electron microscope (TEM) specimens were used for this study. It is shown that a specimen tilt angle of ~30°–40° in the opposite direction of the usual 70° and a smaller working distance in the range 4 mm–5 mm are recommended when using a s-EBSD detector. Specimen thickness and accelerating voltage (Acc.V) have a strong affect on the quality of transmission EBSD patterns and orientation maps. Higher Acc.Vs are generally recommended to get good quality orientation maps. In case of very thin specimens, lowering the Acc.Vs will give better results. In the observation of a thin film of an 8Cr tempered martensite steel specimen, it is confirmed that t-EBSD can provide images and detailed quantitative orientation data comparable with that obtained by TEM. It is also shown that small precipitates of Cr23C6 with sizes around 30 nm could be detected and their orientations measured. 相似文献
78.
Molecular weight dependence of growth and morphology of spherulites of isotactic poly(butene-1), iPB-1, and those of the mixtures with atactic poly(butene-1), aPB-1, were examined by atomic force microscopy (AFM) and polarizing optical microscopy (POM) in order to examine the mechanism of the structural evolution by the branching and re-orientation of lamellar crystals at the growth front. The width of lamellar crystals and the characteristic size of the inner structure of spherulites decreased with increasing molecular weight. The result suggests that the mobility of the melt determines the sizes in spherulites and supports the growth front instability induced by a gradient triggering the branching. The sizes in the mixtures also decreased with increasing weight-averaged molecular weight, Mw. The size dependence in low Mw region, however, was too strong and that in high Mw was too weak in comparison with the predicted dependence for the prepared Mw. It has been concluded that the peculiar behaviors should be discussed with effective Mw influenced by the occurrence of separation and exclusion of non-crystallizing aPB-1 at the growth front. 相似文献
79.
High-rate deposition of hydrogenated amorphous silicon films using inductively coupled silane plasma
Nobuki Sakikawa Yoshinori Shishida Seiichi Miyazaki Masataka Hirose 《Solar Energy Materials & Solar Cells》2001,66(1-4)
Inductively coupled plasma (ICP) generated at 13.56 MHz has been employed for high-rate deposition of device-quality hydrogenated amorphous silicon (a-Si:H). It has been shown that an increase in the flow rate of a monosilane gas enhances the generation rate of deposition precursors, while the ion flux decreases and becomes saturated. The defect density reaches the minimum at a deposition rate of 2.3 nm/s. It has also been demonstrated that even at deposition rates around 4 nm/s, a-Si:H deposited at 150°C exhibits a subgap defect density lower than 6×1016 cm−3 after 12 h AM1 (100 mW/cm2) light soaking. 相似文献
80.
Xin-Tong Zhang Hong-Wu Liu Taketo Taguchi Qing-Bo Meng Osamu Sato Akira Fujishima 《Solar Energy Materials & Solar Cells》2004,81(2):197-203
Al2O3-coated TiO2 porous films were used to fabricate solid-state dye-sensitized solar cells using CuI as hole conductor. Investigation with transient photovoltage measurements showed that the Al2O3 interlayer slowed down the interfacial recombination of electrons in TiO2 with holes in CuI by forming a potential barrier at the TiO2/CuI interface. As a consequence, the cell made from Al2O3-coated TiO2 film showed superior cell performance than the cell made from TiO2 film only, especially under relative high intensity of simulated sunlight. 相似文献