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991.
Masahiro Moriyama Yoshihiro Takao Wen-Xue Wang Terutake Matsubara 《International Journal of Fatigue》2010,32(1):208
An experimental investigation is performed on the quasi-static and cyclic behavior of metal impregnated composites such as Cu–C/C and Si–C/C with a slot together with C/C for comparison. They are expected to be applied to an aircraft brake system. Composites tested are based on a preformed yarn method and their fatigue strength and related characteristics are obtained. Damage mechanisms are discussed and it is concluded that effects of microscopic debonding are quite important to the fatigue response of the present specimen and that the debonding makes the failure mode shift from crack propagation in static loading to bearing in cyclic loading. 相似文献
992.
Nobuhiro Kumada Hideyuki Ogiso Keiko Shiroki Satoshi Wada Yoshinori Yonesaki Takahiro Takei Nobukazu Kinomura 《Materials Letters》2010,64(3):383-385
The solid solution (Ba1−2xBi2x)(CuxTi1− x)O3 (0.0 < x ≤ 0.10) was prepared by conventional high temperature reaction. In the region of x ≤ 0.040 single phases of tetragonal perovskite-type compounds were obtained and the c-axis increased up to x = 0.015 and the maximum of the a/c ratio was 1.0123 at x = 0.010. In x > 0.040 a small amount of an unknown impurity phase appeared in addition to a tetragonal perovskite-type phase. The Curie temperature Tc increased to 140 °C at x = 0.010. Rising Tc was confirmed by temperature dependence of the dielectric constants and the endothermic peaks observed in DTA curves. This is the first example for rising Tc in the solid solution based on BaTiO3 except for doping of Pb2+ ion. 相似文献
993.
Takaaki Tsurumi Motohiro Shono Hirofumi Kakemoto Satoshi Wada Kenji Saito Hirokazu Chazono 《Journal of Electroceramics》2008,21(1-4):17-21
Capacitance aging under DC electric fields has been studied on multilayer ceramic capacitors (MLCCs) with the X7R characteristics. The capacitance change with time was divided into two stages, the first- and the second-stage. The first-stage was due to the nonlinear permittivity of dielectrics and it should not be involved in the aging phenomenon. The second-stage depended on the MnO content, grain size and firing condition of dielectrics. From the behavior of the second-stage, it was concluded that the capacitance aging was caused by the 90-degree domain switching in BaTiO3 in the core. The first-stage was due to the nonlinear permittivity but the domain switching was also included in the first-stage if the domain walls moved by the first application of DC field. The change in the aging behavior with the intensity of DC field could be explained by separating capacitance change into the nonlinear permittivity and the domain switching according to the mechanism proposed in this study. 相似文献
994.
Chihiro Yogi Kazuo Kojima Tomoo Takai Noriyuki Wada 《Journal of Materials Science》2009,44(3):821-827
A TiO2 photocatalytic film was prepared by the sol–gel and dip-coating methods. Au-loaded TiO2 photocatalytic films were produced by the photodeposition method. The photocatalytic activity of the films under UV irradiation
was evaluated by measuring the degradation of absorbance for a methylene blue (MB) aqueous solution. Au particles deposited
on the TiO2 film improved the photocatalytic activity under the O2 bubbling condition. On the other hand, under N2 or Ar bubbling, the doubly reduced form of MB, leuco-methylene blue (LMB), was formed at the beginning of UV irradiation, and then both MB and LMB were decomposed gradually by
the photocatalytic reaction. In this process, Au particles on the TiO2 film behave as electron traps. 相似文献
995.
W. W. Wu A. V. Gubarevich H. Wada O. Odawara 《International Journal of Self-Propagating High-Temperature Synthesis》2011,20(2):94-99
Volume combustion synthesis of NiAl has been applied to joining oxide ceramics. Combustion synthesized joint was found to contain largely the NiAl phase strongly attached to oxide ceramics via the Alrich zones formed at the boundary between combustion synthesized and intermediate layers. 相似文献
996.
This paper gives efficient algorithms for the muiticommodity flow problem for two classes C12 and C01 of planar undirected graphs. Every graph in C12 has two face boundaries B1 and B2 such that each of the source-sink pairs lies on B1 or B2. On the other hand, every graph inC
01 has a face boundaryB
1 such that some of the source-sink pairs lie onB
1 and all the other pairs share a common sink lying onB
1. The algorithms run inO(kn +nT(n)) time if a graph hasn vertices andk source-sink pairs andT(n) is the time required for finding the single-source shortest paths in a planar graph ofn vertices. 相似文献
997.
Ichiro Fujii Ryoichi Yoshida Takahito Imai Seiji Yamazoe Takahiro Wada 《Journal of the American Ceramic Society》2013,96(12):3782-3787
Transparent 0.9Pb(Mg1/3Nb2/3)O3–0.1PbTiO3 (PMN‐PT) based ceramics were prepared by a conventional solid‐state synthesis without using a hot‐press method. The ceramics became transparent when they were sintered in an O2 atmosphere. The optical transmission increased with decreasing diameter of the calcined powder, which was controlled by the size of zirconia ball‐milling media. Substitution of 3 mol% La for Pb in PMN‐PT further increased the optical transmission to 68% at the wavelength of 2000 nm, which was comparable to that of hot‐pressed Pb(Mg1/3Nb2/3)O3‐PbTiO3 based transparent ceramics. 相似文献
998.
Hirose Raita; Suzuki Toshiharu; Moriyama Hideaki; Sato Takao; Yamagishi Akihiko; Oshima Tairo; Tanaka Nobuo 《Protein engineering, design & selection : PEDS》2001,14(2):81-84
Random mutagenesis on thermophilic 3-isopropylmalate dehydrogenases(IPMDH; EC 1.1.1.85) produced mutant enzymes which adapt tolow temperatures. These mutants had higher activity at lowertemperatures than the wild-type enzyme without losing high thermostability.Here we report three structures of the mutants of Thermus thermophilusIPMDH determined by X-ray diffraction which was adapted to alow-temperature environment. Two of them have unstable coenzymebinding states and the other one probably has a stable substratebinding state. The present research suggests that the adaptationis correlated with the binding of either coenzyme or the substrate. 相似文献
999.
The thermoelastic problem of an infinite plate which has a crack or a ribbonlike inclusion and is subjected to remotely uniform heat flow is analyzed under the assumption of linear heat transfer across the flaw. Numerical calculations show that the insulated crack causes an overestimation of the stress singularity, and the insulated inclusion produces an underestimation. 相似文献
1000.