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111.
K.Fujiyama T.Fujiwara Y.Nakatani K.Saito A.Sakuma Y.Akikuni S.Hayashi S.Matsumoto 《金属学报(英文版)》2004,17(4):338-344
Statistical manipulation of material data was conducted for probabilistic life assessment or risk-based design and maintenance for high temperature components of power plants. To obtain the statistical distribution of material properties, dominant parameters affecting material properties are introduced into normalization of statistical variables. Those parameters are hardness, chemical composition, characteristic microstructural features and so on. Creep and fatigue properties are expressed by normalized parameters and the unified statistical distributions are obtained. These probability distribution functions show good coincidence statistically with the field database of steam turbine components. It was concluded that the unified statistical baseline approach is useful for the risk management of components in power plants. 相似文献
112.
Y. Kawabata M. Utsuro S. Hayashi H. Yoshiki 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1988,30(4):557-566
Concentrations and depth distributions of the surface hydrogen and the surface deuterium in vacuum evaporated nickel layers and beryllium plates have been investigated by the ERDA method. It is shown that if the evaporation vacuum pressure is kept better than 10−6 Torr, the hydrogen adsorption from the residual gas during the evaporation is negligible and the hydrogen from residual or atmospheric gases after the evaporation is the main source of the surface hydrogen. Commercial beryllium plates are found to have surface hydrogen of about 1016 atoms cm2. Deuterium treated samples, either in D2 gas or heavy water, do not show more than possibly a partial replacement of hydrogen. The influence of substrates is small if the thickness of the evaporated nickel layer is more than 2000 Å. The measurements are in good agreement with previously published results. 相似文献
113.
A methodology for realizing a higher‐power‐density DC‐DC converter has been proposed for a power unit installed in a 380‐V DC distribution system. The possibility of the converter design will be strengthened by using the series–parallel connection topology for isolated DC‐DC converters. A converter prototype with a power density of 10 W/cm3 has been fabricated, and the feasibility of the converter design has been confirmed experimentally. This result contributes to the realization of a highly efficient and highly space‐saving 380‐V DC distribution system. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(3): 51–62, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22494 相似文献
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115.
Keiichiro Sugimoto Sayaka Sakamoto Kazuya Nakagawa Shuichi Hayashi Naoki Harada Ryoichi Yamaji Yoshihisa Nakano Hiroshi Inui 《Food chemistry》2011
Eucalyptus leaf extract (ELE) is rich in hydrolyzable tannins. We examined the effects of ELE and its constituents on lipopolysaccharide (LPS)-induced liver injury in mice. Mice fed a diet supplemented with 1% ELE were intraperitoneally administered LPS. Six hours later, the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were significantly lower in the ELE-supplemented mice than in the controls; LPS-induced hepatic inducible nitric oxide synthase (iNOS) expression was also suppressed. ELE lowered LPS-stimulated iNOS expression in cultured RAW 264.7 macrophages. Furthermore, the aglycones of hydrolyzable tannins, gallic acid (GA) and ellagic acid (EA), inhibited iNOS induction to a greater extent than did ELE (15-fold higher). When mice were fed a 1% GA or EA diet, the increase in the serum ALT and AST activities and hepatic iNOS expression in response to the LPS challenge were significantly attenuated. Thus, hydrolyzable tannins in ELE ameliorate LPS-induced liver injury. 相似文献
116.
Fast and Almost Complete Nitridation of Mesoporous Silica MCM-41 with Ammonia in a Plug-Flow Reactor
Fumitaka Hayashi Ken-ichi Ishizu Masakazu Iwamoto 《Journal of the American Ceramic Society》2010,93(1):104-110
The title reaction proceeded well to yield silicon (oxy)nitride at 973–1323 K using a plug-flow reactor. The degree of nitridation was studied as a function of temperature and time of nitridation, the sample weight, and the flow rate of ammonia. It was dependent on the reaction temperature and the amount of ammonia supplied per sample weight. The nitridation at 1273 K for 10–25 h yielded the oxynitride with 36–39 wt% nitrogen, which was very close to 40 wt% of Si3 N4 . Characterization with X-ray diffraction, field-emission scanning electron microscopy and transmission electron microscopy measurements, and nitrogen adsorption revealed the conversion of MCM-41 to the corresponding oxynitride without essential loss of the mesoporous structure, the decrements of the lattice constant and the pore diameter by 20–35%, and the increments of the wall thickness by ca. 45%. Solid-state 29 Si nuclear magnetic resonance spectra during the nitridation clearly showed fast decrease in SiO4 species and slow in SiO3 (OH). Various intermediate species, SiO x N y (NH2 or NH) z , were observed to be formed and finally, ca. 70% SiN4 species, ca. 20% SiN3 (NH2 or NH), and ca. 10% SiON2 (NH2 or NH) were produced, being consistent with the results of the above mentioned elemental analysis. 相似文献
117.
O. Snigirev M. Hayashi S. Fukumoto Y. Hatsukade Y. Katsu S. Tanaka 《Journal of Superconductivity and Novel Magnetism》2011,24(1-2):1033-1036
We constructed and studied an ultra low-field nuclear magnetic resonance imaging system using a HTS rf SQUID and room-temperature coils. We recorded the free induction decay signals of 1H by employing a measuring field, B m, of 44.8???T and a polarizing field, B p, of 36.8?mT; in the presence of ? B Z /? z and ? B Z /? y gradients of the order of 0.8???T/m, we were able to obtain a quasi two-dimensional 4-pixels image of a simple water phantom. 相似文献
118.
119.
Y Hayashi M
M
R Talukder Jinchuan Wu T Takeyama T Kawanishi N Simizu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2001,76(8):844-850
The activity of Chromobacterium viscosum lipase (glycerol‐ester hydrolase, EC 3.1.1.3) entrapped in AOT/isooctane and AOT/Tween 85/isooctane reverse micelles was significantly increased by the addition of short chain methoxypolyethylene glycols (MPEGs), taking the hydrolysis of olive oil as a model reaction. The molecular weight of MPEG had a strong effect on the lipase activity, and MPEG of nominal molecular weight 550 was found to be the most effective. To optimize the factors affecting enzymatic hydrolysis of olive oil in reverse micellar systems containing MPEG 550, the effect of various parameters, such as Wo (molar ratio of water to surfactant), pH, ionic strength, surfactant concentration and temperature were investigated. A kinetic model considering the substrate adsorption equilibrium between the bulk phase of organic solvent and the micellar phase was also successfully used to understand the enzyme activity in the presence of MPEG 550. Both the Michaelis constant and the substrate adsorption equilibrium constant were obviously reduced as compared with those obtained in the simple AOT reverse micellar system. © 2001 Society of Chemical Industry 相似文献
120.
Shaoying Lu Michailova A. Saucerman J. Yuhui Cheng Zeyun Yu Kaiser T. Li W. Bank R. Holst M. Mccammon J. Hayashi T. Hoshijima M. Arzberger P. McCulloch A. 《IEEE engineering in medicine and biology magazine》2009,28(2):46-57
This paper indicates that in ventricular myocytes when the SR (sarcoplasmic reticulum) is pharmacologically inhibited, the intracellular Ca2+concentration rapidly increases during Ca2+ entrance (0-70 ms), whereas the decay of Ca2+ is slow; in the absence of fluorescent dye, large Ca2+ concentration gradients might develop near the cell membrane; intracellular Ca2+ distribution is tightly regulated by the localization of Ca2+transporter proteins along the sarcolemma and strongly relays on the presence of mobile and stationary Ca2+ buffers. These studies also imply that in ventricular cells with intact and functional SR, the Ca2+ signal most likely would spread faster along the t-tubular system, surface membrane than to the cell interior and that in the absence of Ca2+ dye high Ca2+ gradients under the surface membrane and more uniform Ca2+ distribution in the cell interior might be expected. 相似文献