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251.
A. Belyakov Y. Sakai T. Hara Y. Kimura K. Tsuzaki 《Metallurgical and Materials Transactions A》2001,32(7):1769-1776
The microstructure and the strength of an iron mechanically milled with various amounts of oxygen (i.e., 0.2, 0.6, and 1.5 mass pct) were studied. The samples were subjected to a mechanical milling in an argon atmosphere for
100 hours followed by consolidating bar rolling to a total reduction of about 86 pct at 700 °C. The microstructure of the
steels sensitively changed depending on the oxygen content, i.e., on the volume fraction of the oxide particles. The average grain size decreased from about 0.7 to 0.2 μm with an increase in the amount of oxygen. Moreover, the misorientation distributions of the grain boundaries were different
in the samples with various amounts of oxygen. A relatively large fraction of low-angle boundaries arranged crosswise to the
rolling axis was registered in the samples with 0.2 and 0.6 pct oxygen, while the near random distribution of the boundary
misorientations was obtained in the specimens with 1.5 pct oxygen. The effect of dispersed particles on the structure evolution
and the relationship between microstructures and some mechanical properties are discussed. 相似文献
252.
Go Hitoki Tsuyosi Takata Shigeru Ikeda Michikazu Hara Junko N. Kondo Masato Kakihana Kazunari Domen 《Catalysis Today》2000,63(2-4):175-181
Simple transition metal oxides such as NiO, Co3O4, Fe3O4 and Cu2O were found to catalytically decompose water into H2 and O2 by mechanical energy. The reaction is regarded as “mechano-catalytic” overall water splitting” and is a quite novel catalytic reaction. In this paper, some general aspects on the mechano-catalytic overall water splitting are reviewed on simple oxides. In addition, recent results on the mechano-catalytic activity of a groups of mixed oxides, wolramite-type oxides with a formula of ABO4 (A=Fe, Co, Ni and Cu, etc., B=W, Mo), are shown. AWO4 (A=Fe, Co, Ni and Cu) decomposed water into H2 and O2 under the supply of mechanical energy, indicating that mechano-catalytic overall water splitting proceeded on wolframite-type compounds containing 3d-transition metals. AMoO4 (A=Fe, Co, Ni) also decomposed water into H2 and O2 under supply of mechanical energy. The reaction properties on wolframite-type oxides are discussed. 相似文献
253.
Nakamura K. Hara T. Yoshida M. Miyahara T. Ito H. 《Quantum Electronics, IEEE Journal of》2000,36(3):305-316
This paper describes the theoretical and experimental study of a new technique for optical frequency domain ranging (OFDR) by a frequency-shifted feedback (FSF) laser. In conventional OFDR, a frequency chirped single-mode laser is used as a light source to convert a distance into a beat frequency, and a tradeoff exists between measurement range and resolution. The FSF laser output consists of periodically generated chirped frequency components whose chirp rate is faster than 100 PHz/s (P=1015), By use of the FSF laser, the tradeoff is removed and long-distance high-resolution OFDR is realized In the experiment, a distance of 18.5 km was measured with a resolution of 20 mm 相似文献
254.
Hossam A. Gabbar Hanaa E. Sayed Hara Masanobu 《Reliability Engineering & System Safety》2009,94(8):1289-1298
Fault simulator is proposed to understand and evaluate all possible fault propagation scenarios, which is an essential part of safety design and operation design and support of chemical/production processes. Process models are constructed and integrated with fault models, which are formulated in qualitative manner using fault semantic networks (FSN). Trend analysis techniques are used to map real time and simulation quantitative data into qualitative fault models for better decision support and tuning of FSN. The design of the proposed fault simulator is described and applied on experimental plant (G-Plant) to diagnose several fault scenarios. The proposed fault simulator will enable industrial plants to specify and validate safety requirements as part of safety system design as well as to support recovery and shutdown operation and disaster management. 相似文献
255.
Noriyuki Hayashi Tetsuo Sugahara Shin‐Ichiro Tsuru Masanori Hara 《IEEJ Transactions on Electrical and Electronic Engineering》2006,1(2):194-206
A centrifugal method was used to fabricate large‐scale functionally graded materials (FGMs) from solid‐particles/viscous‐matrix mixtures at room temperature. The conventional simulation procedure of the centrifugal process was improved by considering the dependency of the viscosity η of the mixture on the packing fraction νp of particle, the effects of arbitrary shape of the actual fillers on η, the statistical dispersion of the diameters of the actual fillers, and the formation and growth of the fully packed layer (FPL) near the FGM bottom. The new simulation method was applied to three centrifugal processes employed for experimental FGM fabrications from alumina/epoxy mixtures. The numerical profiles of νp are in good agreement with the experimental ones regardless of the shapes of fillers and 'ponding viscosity of the solutions without fillers, the total amount of fillers loaded, and the centrifugal conditions. The saturating nature of νp near the far end of the FGM column is also simulated with reasonable precision. Finally, the manner in which the particles exert varying influences on the gradient of νp is demonstrated: the particles exhibit different movements depending on their size. On the basis of these results, the effectiveness of the new simulation method proposed is confirmed for the modeling of similar processes involved in the fabrication of FGMs from solid‐particles/viscous‐matrix mixtures by the centrifugal method. © 2006 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
256.
Chan Zhong Qiu-Feng Cai Guang-Ming Liu Le-Chang Sun Kenji Hara Wen-Jin Su Min-Jie Cao 《Food chemistry》2012
The modori phenomenon during surimi production is caused by endogenous proteinases, especially cathepsin L and myofibril-bound serine proteinase (MBSP). Cathepsin L from the skeletal muscle of blue scad (Decapterus maruadsi) was purified to homogeneity by ammonium sulphate fractionation and a series of column chromatographies and revealed a single band with molecular mass of 30 kDa on SDS–PAGE. Peptide mass fingerprinting (PMF) obtained three fragments with 48 amino acid residues, which were highly identical to cathepsin L from other fish species. Its optimal pH and temperature were 5.5 and 55 °C, respectively. Meanwhile, MBSP was purified from the skeletal muscle of blue scad, and the roles of cathepsin L and MBSP in the degradation of myofibrillar proteins were compared. The results indicated that MBSP is more effective than cathepsin L in promoting the degradation of myofibrillar proteins, especially myosin heavy chain (MHC), suggesting that MBSP plays a more significant role. 相似文献
257.
M Hara YM Liu L Zhen IS Cohen H Yu P Danilo K Ogino JP Bilezikian MR Rosen 《Canadian Metallurgical Quarterly》1997,96(10):3704-3709
BACKGROUND: The classic calciotropic hormone parathyroid hormone (PTH) and its paracrine factor parathyroid hormone-related protein (PTHrP) both increase heart rate. METHODS AND RESULTS: We used standard electrophysiological techniques to study the effects of PTH and PTHrP on isolated rabbit sinus node, isolated canine Purkinje fibers, and disaggregated rabbit sinus node myocytes. Sinus node maximum diastolic potential, activation voltage, and amplitude were unchanged by PTH or PTHrP (P>.05). However, the slope of phase 4 and the automatic rate were increased at PTH and PTHrP > or = 10 nmol/L (P<.05). Comparable results were seen in canine Purkinje fibers. We then used the perforated-patch technique to study the I(f) pacemaker current in sinus node. PTH 12.5 nmol/L and PTHrP 12.5 to 18 nmol/L increased I(f) at -65 mV by 68+/-41% (n=5) and 69+/-50% (n=5), respectively. Actions of both agents were reversible. The increase in I(f) appeared to result from a change in maximal conductance and not a shift in the voltage dependence of activation. CONCLUSIONS: These observations provide, for the first time, direct electrophysiological support for the chronotropic actions of PTH and PTHrP. They suggest that classic hormones and paracrine factors can have multiple functions and that in the case of PTH and PTHrP, a newly recognized action is to alter automaticity directly. 相似文献
258.
259.
Prof. Dr. Midori A. Arai Kota Sakuraba Yoshinori Makita Dr. Yasumasa Hara Prof. Dr. Masami Ishibashi 《Chembiochem : a European journal of chemical biology》2021,22(18):2799-2804
Pulmonary arterial hypertension (PAH) is a rare and severe progressive disorder characterized by high pulmonary artery pressure. Chronic hypoxia causes a metabolic disorder and the Warburg effect in pulmonary arterial smooth muscle cells (PASMCs). Pyruvate dehydrogenase kinase 1 (PDK1) is a key enzyme in Warburg effect increased by hypoxia-inducible factor (HIF-1). We constructed a cell-based luciferase assay system for HIF-1 inhibitors. Using this system, six HIF-1 inhibitors were identified. Among these inhibitors, the effect of tagitinin C ( 1 ) on PASMC was investigated. Tagitinin C ( 1 ) clearly decreased the amount of HIF-1β and the HIF-1 target PDK1. This result indicates that HIF-1 inhibitors effectively decrease PDK1 activity, which is a cause of the metabolic disorder and Warburg effect observed in PASMCs. Identifying naturally occurring HIF-1 inhibitors could provide novel insights into the development of PAH medications. 相似文献
260.