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121.
Kyosuke Yoshimi Shuji Hanada 《JOM Journal of the Minerals, Metals and Materials Society》1997,49(8):46-49
For the development of Fe−Al alloys as structural materials, a deep understanding of slip and deformation properties is necessary.
In particular, since mechanical properties of the iron aluminides are affected by excess vacancy strengthening as well as
the positive-temperature dependence of yield stress, controlling these strength features is essential. In this article, the
strength properties of iron aluminides are reviewed.
Author’s Note: All compositions are provided in mole percent.
Kyosuke Yoshimi earned his Ph.D. in materials science and engineering at Tohoku University in 1997. He is currently a research associate
at Tohoku University.
Shuji Hanada earned his Ph.D. in materials science and engineering at Tohoku University. He is currently a professor at Tohoku University.
Dr. Hanada is also a member of TMS. 相似文献
122.
Matsuki M. Ueda T. 《IEEE transactions on pattern analysis and machine intelligence》1989,11(11):1225-1228
A real-time sectional image measuring system is developed using the time-sequentially-coded grating method, and its application to automatic 3D image data measuring systems is studied. A PLZT electron shutter array is used to project time-sequentially-coded grating patterns on the object. The sectional image is calculated from deformed grating images which are picked up by a TV camera. This system takes about 530 ms to project the 100-slit time-sequentially-coded grating patterns and about 30 ms to calculate one sectional image 相似文献
123.
Jones et al. have reported that the epsilon-carbons of methionine residues in myoglobin can be enriched with stable isotope (13C) in two steps, i.e., methylation of methionine residues with 13CH3I in the protein and thiolysis using dithiothreitol [Jones, W.C., Rothgeb, T.M., and Gurd, F.R.N. (1976) J. Biol. Chem. 251,7452-7460]. Using their method, we failed to prepare active lysozyme in which the epsilon-carbons of methionine residues are enriched with 13C, because many side reactions took place under the thiolysis condition (pH 10.5, 37 degrees C). When we employed 2-aminothiophenol as a reagent for thiolysis, the reduction proceeded under a weakly acidic condition to afford fully active lysozyme, in which the epsilon-carbons of two methionine residues were enriched with 13C, in a 30% yield. Analysis of the 13C-edited NOESY spectra of 13C-enriched methionine lysozyme in the absence and presence of a substrate analogue indicated the occurrence of conformational change around Met 105 in lysozyme. 相似文献
124.
H. Abe M. Morikawa T. Ueda R. Nomura Y. Okuda 《Journal of Low Temperature Physics》2008,150(3-4):289-294
We report an instability of 4He crystal surface during a large modification of its shape observed by schlieren photography. 4He crystal was nucleated on an ultrasound transducer which was placed in the upper part of the sample cell facing the bottom.
The crystal was grown on the transducer and the lowest part of it eventually touched the bottom of the cell. Almost immediately,
the crystal started to change shape very quickly to adjust itself to the new boundary condition. During this large deformation,
the hexagonal shape of the crystal surrounded by facets became unstable and the surface became corrugated. The corrugation
pattern during the deformation was observed by a high-speed camera. The results were compared with Kelvin-Helmholtz type instability
which Uwaha and Nozières predicted.
相似文献
125.
126.
Transient stability may be seriously affected when a large number of distributed generators (DG) stop simultaneously during voltage sag. It is necessary to analyze accurately the dynamics of bulk power systems with high DG penetration. In this paper, transient stability is studied by analyzing power‐angle curves of generators while considering load dynamics and model order reduction at lower voltages. Based on the analysis, a decrease in the load internal resistance after voltage sag causes transient instability of generators. The phenomenon is confirmed through simulation using a one‐machine and one‐load model. This paper also suggests that the simulation results might be misled by traditional bulk power system modeling such as using the static load model and ignoring impedance at lower voltages. As for the numerical simulation, a large level of DG stoppage leads to transient step out in a bulk power system, and the stability is greatly improved by DG voltage regulation. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(2): 20– 29, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20608 相似文献
127.
Manufacturing exists to create value. However, historically, discussion of economic issues in manufacturing primarily emphasizes cost. It is becoming more difficult to understand and control values of products and services in response to rapid globalization and networking. This paper presents a discussion of the nature of value considering a history of axiology, design problems of artifacts, social dilemmas, network externalities, and sustainability. Promising academic methodologies are presented herein with emphasis on transdisciplinary and synthetic approaches. Value creation models based on Emergent Synthesis and co-creative decision-making are presented. This paper involves some important study examples of service and production toward sustainable value creation in society. 相似文献
128.
Ceramide-Induced Apoptosis in Renal Tubular Cells: A Role of Mitochondria and Sphingosine-1-Phoshate
Norishi Ueda 《International journal of molecular sciences》2015,16(3):5076-5124
Ceramide is synthesized upon stimuli, and induces apoptosis in renal tubular cells (RTCs). Sphingosine-1 phosphate (S1P) functions as a survival factor. Thus, the balance of ceramide/S1P determines ceramide-induced apoptosis. Mitochondria play a key role for ceramide-induced apoptosis by altered mitochondrial outer membrane permeability (MOMP). Ceramide enhances oligomerization of pro-apoptotic Bcl-2 family proteins, ceramide channel, and reduces anti-apoptotic Bcl-2 proteins in the MOM. This process alters MOMP, resulting in generation of reactive oxygen species (ROS), cytochrome C release into the cytosol, caspase activation, and apoptosis. Ceramide regulates apoptosis through mitogen-activated protein kinases (MAPKs)-dependent and -independent pathways. Conversely, MAPKs alter ceramide generation by regulating the enzymes involving ceramide metabolism, affecting ceramide-induced apoptosis. Crosstalk between Bcl-2 family proteins, ROS, and many signaling pathways regulates ceramide-induced apoptosis. Growth factors rescue ceramide-induced apoptosis by regulating the enzymes involving ceramide metabolism, S1P, and signaling pathways including MAPKs. This article reviews evidence supporting a role of ceramide for apoptosis and discusses a role of mitochondria, including MOMP, Bcl-2 family proteins, ROS, and signaling pathways, and crosstalk between these factors in the regulation of ceramide-induced apoptosis of RTCs. A balancing role between ceramide and S1P and the strategy for preventing ceramide-induced apoptosis by growth factors are also discussed. 相似文献
129.
Takeshi Takahashi Kyosuke Kojima Wei Zhang Kanae Sasaki Masaru Ito Hironori Suzuki Masato Kawasaki Soichi Wakatsuki Terunao Takahara Hideki Shibata Masatoshi Maki 《International journal of molecular sciences》2015,16(2):3677-3699
ALG-2, a 22-kDa penta-EF-hand protein, is involved in cell death, signal transduction, membrane trafficking, etc., by interacting with various proteins in mammalian cells in a Ca2+-dependent manner. Most known ALG-2-interacting proteins contain proline-rich regions in which either PPYPXnYP (type 1 motif) or PXPGF (type 2 motif) is commonly found. Previous X-ray crystal structural analysis of the complex between ALG-2 and an ALIX peptide revealed that the peptide binds to the two hydrophobic pockets. In the present study, we resolved the crystal structure of the complex between ALG-2 and a peptide of Sec31A (outer shell component of coat complex II, COPII; containing the type 2 motif) and found that the peptide binds to the third hydrophobic pocket (Pocket 3). While amino acid substitution of Phe85, a Pocket 3 residue, with Ala abrogated the interaction with Sec31A, it did not affect the interaction with ALIX. On the other hand, amino acid substitution of Tyr180, a Pocket 1 residue, with Ala caused loss of binding to ALIX, but maintained binding to Sec31A. We conclude that ALG-2 recognizes two types of motifs at different hydrophobic surfaces. Furthermore, based on the results of serial mutational analysis of the ALG-2-binding sites in Sec31A, the type 2 motif was newly defined. 相似文献
130.
In single-objective optimization problems, with only one optimal design objective, the absolute optimal solution to maximize/minimize the objective function can be determined. However, in most real design problems, the optimization problems are multi-objective, where two or more independent design objectives must be optimized simultaneously, and no single absolute optimal solution necessarily exists. In these cases, it is helpful for designers to recognize the range of alternative solutions that exist in Pareto-optimal sets and choose an acceptable solution from among them. In this paper, the authors carried out multi-objective optimization using Multiple Objective Genetic Algorithms through a real case study involved in indoor environmental design – the design of outer windows. Then the authors analyzed structure of Pareto-optimal solution sets. Here we present the analysis process as well as the case study details, and show how the method proposed here is effective at finding an acceptable solution for multi-objective optimization problems. 相似文献