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排序方式: 共有559条查询结果,搜索用时 190 毫秒
131.
Hiroki Habazaki Shao-Qien Ding Asahi Kawashima Katsuhiko Asami Koji Hashimoto Akihisa Inoue Tsuyoshi Masumoto 《Corrosion Science》1989,29(11-12)
An amorphous Ni-19P alloy prepared by rapid quenching of white heat melt showed a higher anodic dissolution current density in 1 N HCl in comparison with the same amorphous alloy prepared by rapid quenching of red heat melt. After structural relaxation these two specimens showed the same anodic polarization curve which is located between the polarization curves of as-quenched two specimens. The thermograms of these two as-quenched specimens were different from each other, showing that the difference in the amorphous states is due to the difference in structural relaxation during preparation. The difference in anodic behavior between these two as-quenched specimens seems due to the difference in the amounts of quenched-in defects. The higher current density of the relaxed specimen in comparison with the as-quenched specimen prepared by rapid quenching of the red heat melt has been interpreted in terms of introduction of chemical heterogeneity as a result of rearrangement and regroupings of atoms in the alloy during structural relaxation. The steady state current density was fairly low in the low potential region without showing a difference between two as-quenched specimens and then increased with increasing polarization potential. The difference in the quality of as-quenched alloy specimens seemed to be masked by the formation of phosphorus-covered alloy surfaces during anodic polarization at potentials lower than about 200 mV(SCE), because of a negligibly small dissolution rate constant of phosphorus in comparison with that of nickel. 相似文献
132.
A unique method previously proposed by the authors was applied to the heat transfer augmentation in the flow boiling field. In this method a screen sheet was placed on the horizontal heated surface where bubble nucleation occurred. Generated vapor bubbles were trapped between the screen and the wall, became flat, and moved along the surface. This restricted bubble behavior caused the heat transfer enhancement. Three types of screen sheet were tested in the present experiment and the effect of the screen on the heat transfer and two‐phase flow characteristics was investigated. In two of these cases, the screen was displaced upward by the bubble nucleation. Compared with the ordinary flow boiling case, heat transfer was enhanced by a factor of 1.2 to 6 within the present experimental range. Using a simple flow model, it was made clear that the effect of the height of the displaced screen was important in evaluating the increase in pressure drop. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(4): 319–329, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10094 相似文献
133.
Katsumi Morikawa Katsuhiko Takahashi Daisuke Hirotani 《Journal of Intelligent Manufacturing》2018,29(3):509-518
This study is concerned with the problem of reducing the waiting times of outpatients. Both scheduled patients and walk-ins are included among the outpatients to reflect the typical medical environment in Japan. The consultation time of a hospital is divided into several blocks, and each scheduled patient is given the start time of a block as his or her scheduled time of the consultation as an appointment. It is assumed that all scheduled patients arrive at the hospital at their scheduled times, while walk-ins arrive randomly. A set of candidate appointment schedules is given, and the process of selecting promising schedules in terms of average waiting times is the focus of the work. To support the selection process without conducting a conventional simulation, the notion of a clearing function is adopted to evaluate each candidate schedule. The clearing function of a system gives the expected output or throughput of the system under varying levels of workload of the system. Although it is necessary to conduct exploratory experiments in advance to obtain the clearing function, the expected waiting time can be estimated by simple calculations with the aid of the clearing function. The average waiting times of four schedules in two scenarios are calculated and compared with those obtained from conventional simulations. It is revealed that the proposed procedure based on the clearing function gives acceptable estimated average values. 相似文献
134.
Tensile failure mechanisms in type I carbon fibre-reinforced epoxy resin have been studied by examining the modes of failure of cured and semi-cured CFRP and of fibre bundle specimens. The rigid matrix in the cured material modified the appearance of the fractured specimen but by detecting the acoustic emission generated during loading the basic fibre bundle behaviour was found to exert a major influence on fracture. Microscopic examination of fractured CFRP specimens has revealed that consecutive fibre failure may be restricted to sub-bundles as a result of shearing between these sub-bundles, and that the material is weakened by a number of internal failures that are not necessarily connected. Ultimate failure seems to be statistically determined and it is a characteristic of the material that some scatter in the strength of CFRP must be expected. 相似文献
135.
Jun'ichiro Hara Yoshimasa A. Ono Katsuhiko Nagai Kiyoshi Kawamura 《Journal of Low Temperature Physics》1980,39(5-6):603-621
The shear viscosity (T) of superfluid 3He-B is studied throughout the temperature region 0t1 (t=T/T
c). The Boltzmann equation for Bogoliubov-Valatin quasiparticles is solved by a variational method. In the calculation of the collision integral, the scattering amplitude is estimated in the s-p-d-wave approximation by taking into account the spin-dependent part as well as the spin-independent part. The reduced shear viscosity % MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-qqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xHapdbiqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaacaaeaacq% aH3oaAaiaawoWaaiabg2da9iabeE7aOHqaciaa-HcaieaacaGFubGa% a8xkaGGaciab99caViabeE7aOjaa-HcacaGFubWaaSbaaKqaGgaaca% WFJbaaleqaaOGaa8xkaaaa!440E!\[\widetilde\eta = \eta (T)/\eta (T_c )\] in this approximation is smaller than those in the s-wave and s-p-wave approximations at all temperatures. The numerical result for \~ in the s-p-d- wave approximation is in good agreement with the recent experimental data of Parpia et al. and of Alvesalo et al. in the temperature range 0.5.t1.0.Supported in part by the Nishina Memorial Foundation and in part by the NSF under Grant No. DMR-76-24011. 相似文献
136.
Arai MA Matsuo I Hagihara S Totani K Maruyama J Kitamoto K Ito Y 《Chembiochem : a European journal of chemical biology》2005,6(12):2281-2289
Calnexin (CNX) and its soluble homologue calreticulin (CRT) are lectin-like molecular chaperones that help newly synthesized glycoproteins to fold correctly in the rough endoplasmic reticulum (ER). To investigate the mechanism of glycoprotein-quality control, we have synthesized structurally defined high-mannose-type oligosaccharides related to this system. This paper describes the synthesis of the non-natural undecasaccharide 2 and heptasaccharide 16, designed as potential inhibitors of the ER quality-control system. Each possesses the key tetrasaccharide element (Glc1Man3) critical for the CNX/CRT binding, while lacking the pentamannosyl branch required for glucosidase II recognition. These oligosaccharides were evaluated for their ability to bind CRT by isothermal titration calorimetry (ITC). As expected, each of them had a significant affinity towards CRT. In addition, these compounds were shown to be resistant to glucosidase II digestion. Their activities in blocking the chaperone function of CRT were next measured by using malate dehydrogenase (MDH) as a substrate. Their inhibitory effects were shown to correlate well with their CRT-binding affinities, both being critically dependent upon the presence of the terminal glucose (Glc) residue. 相似文献
137.
Katsuhiko Muroyama Masahiro Yamasaki Eiji Shibutani 《Chemical engineering science》2005,60(22):6360-6370
In the present study, we developed a novel simulation model of the U-tube reactor for treating drinking water, which is composed of a coaxial inner tube serving as an efficient concurrent down-flow ozone dissolver and an outer column carrying out reactions between ozone and organic substances including odorous materials (2-methylisoborneol: 2-MIB) dissolved in the raw water. We assume that the U-tube is composed of a plug flow section (inner tube) followed by a tanks-in-series section (outer bubble column) and take into account the effect of the hydrostatic pressurization on the flow and absorption equilibrium for the gaseous components including ozone and other inactive species in developing the mass balance models. An algorithm is constructed of the differential multiple mass balance equations for the inner tube sections and multiple difference mass balance equations in the series tanks in the outer column section to enable the scale-up from a pilot plant to a full-scale plant. The gas holdup and gas-liquid mass transfer coefficient were measured in a model reactor and correlated for the use of the simulation calculation. Available literature data and correlations on the rates of reactions between ozone and organic substances including odorous material 2-MIB, gas-liquid equilibrium for active and inactive gases and axial fluid mixing properties are also incorporated in the simulation calculation. The simulation results well explained the available data of the ozone absorption efficiency and the removal efficiency of the odorous material in a pilot U-tube reactor. The simulation procedure was also successfully extended to verify the performance of a full-scale U-tube reactor. It is shown that the ozone absorption is practically a single function of the gas/liquid ratio while the removal efficiency of the odorous material is a single function of the ozone dose for a specified U-tube configuration. 相似文献
138.
Kenji Hashimoto Katsuhiko Muroyama Shinji Nagata 《Journal of the American Oil Chemists' Society》1971,48(6):291-295
Hydrogenation results for fatty oils were analyzed by using a nonlinear least squares method. The rate of the hydrogenation
for diunsaturated fatty groups to monounsaturated groups and the rate of the geometrical isomerizations between monounsaturated
groups were found to be half order with respect to hydrogen concentration, whereas the hydrogenation rate of monounsaturated
groups was the first order. A detailed reaction mechanism is presented to explain the kinetic behavior. 相似文献
139.
Hideaki Mitsui Katsuhiko Mizuno Nobuo Ueno Kazuyuki Sugita 《Polymer Engineering and Science》1992,32(20):1541-1544
A simple alternative was studied for the tri-layer resist system. One single thick layer of resist polymer was surface silylated to obtain a bilevel structure that functioned similarly to the bilayer resist composed of the Si-containing top imaging and the bottom planalizing layers. A resist or matrix polymer layer containing phenolic – OH groups was silylated by exposing it to hexamethyldisilazane vapor, and Si atoms were effectively incorporated in the surface sublayer by limited gas permeation and reaction with the – OH groups. Oxygen RIE durability of the silylated poly(vinyl phenol) or the positive-working commercial EB resist, RE-5000P, was > 10 times as high as that of PVP or RE-5000P before silylation. The surface silylated single-layer (SSS) resist derived from RE-5000P was flood-exposed through a mesh mask to 11.7°C/cm2 of 4 KeV electrons, developed with tetramethylammonium hydroxide in aqueous methanol, and plasma-developed in an O2 RIE chamber to form a positive-tone relief image. 相似文献
140.
Takeshi Matsumoto Won Young Kim Masahiro Kishida Hideo Nagata Katsuhiko Wakabayashi 《Catalysis Letters》1994,24(3-4):391-394
We present here some results on Ir-Mo-Rh metallic catalysts for the synthesis of C2-C4 alcohols from syngas. It was found that Ir-Mo-Rh supported on silica containing small amounts of Rh exhibited much higher activity for CO hydrogenation than Ir-Mo bimetallic catalyst. The selectivity to various alcohols did not change very much upon the addition of Rh. The activity was greatly affected by the impregnation procedure of the metals in the catalyst preparation. 相似文献