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71.
In this paper, we investigate the Gauss maps of a Ricci-mean curvature flow. A Ricci-mean curvature flow is a coupled equation of a mean curvature flow and a Ricci flow on the ambient manifold. Ruh and Vilms (Trans Am Math Soc 149: 569–573, 1970) proved that the Gauss map of a minimal submanifold in a Euclidean space is a harmonic map, and Wang (Math Res Lett 10(2–3):287–299, 2003) extended this result to a mean curvature flow in a Euclidean space by proving its Gauss maps satisfy the harmonic map heat flow equation. In this paper, we deduce the evolution equation for the Gauss maps of a Ricci-mean curvature flow, and as a direct corollary we prove that the Gauss maps of a Ricci-mean curvature flow satisfy the vertically harmonic map heat flow equation when the codimension of submanifolds is 1. 相似文献
72.
In this paper, we determine the type numbers of the pseudo-hyperbolic Gauss maps of all oriented Lorentzian surfaces of constant mean and Gaussian curvatures and non-diagonalizable shape operator in the 3-dimensional anti-de Sitter space. Also, we investigate the behavior of type numbers of the pseudo-hyperbolic Gauss map along the parallel family of such oriented Lorentzian surfaces in the 3-dimensional anti-de Sitter space. Furthermore, we investigate the type number of the pseudo-hyperbolic Gauss map of one of Lorentzian hypersurfaces of B-scroll type in a general dimensional anti-de Sitter space. 相似文献
73.
Kazuto Koike Gen-you Takada Kazuya Fujimoto Shigehiko Sasa Masataka Inoue Mitsuaki Yano 《Physica E: Low-dimensional Systems and Nanostructures》2006,32(1-2):191
Thermal stability of single-crystalline [ZnO]m[Zn0.7Mg0.3O]n multiple quantum wells (MQWs) grown on a-plane sapphire substrates by plasma-assisted molecular beam epitaxy is reported. X-ray diffraction analysis revealed that these MQWs were grown as designed with a fixed Zn0.7Mg0.3O barrier width of and a series of ZnO well widths of . Cathodoluminescence spectra from these MQWs consisted of two major peaks; one was the emission from the bound excitons in Zn0.7Mg0.3O barrier layers, and the other was that from the confined excitons in ZnO well layers. These structural and optical properties were found to be dramatically changed by the ex situ annealing treatments over 700 °C. These changes were presumably due to the onset of phase separation of the Zn0.7Mg0.3O barrier layers with pronounced Mg diffusion toward the ZnO wells. 相似文献
74.
C. Kimura B. Beckford T. Fujibayashi T. Fujii Y. Fujii K. Futatsukawa T. Gogami O. Hashimoto Y. C. Han K. Hirose R. Honda K. Hosomi A. Iguchi T. Ishikawa H. Kanda Y. Kaneko M. Kaneta Y. Kasai T. Kawasaki S. Kiyokawa T. Koike K. Maeda N. Matsubara K. Miwa Y. Miyagi S. Nagao S. N. Nakamura A. Okuyama H. Shimizu T. Tamae H. Tamura N. Terada K. Tsukada F. Yamamoto T. O. Yamamoto H. Yamazaki 《Few-Body Systems》2013,54(7-10):1319-1322
Double charged pion photoproductions from the deuteron have been studied at Research Center for Electron Photon Science (ELPH), Tohoku University. Tagged photon beams in an energy range of 0.67 ≤ E γ ≤ 1.08 GeV were impinged on the liquid deuteron target. Produced charged particles were observed with the Neutral Kaon Spectrometer2 (NKS2). The γ d → π + π ? d process was clearly separated among the three charged tracks. We obtained the photon energy dependence of the normalized yields of this process. 相似文献
75.
Hiroki Kanda Brian Beckford Takeji Fujibayashi Takao Fujii Yu Fujii Kenta Futatsukawa Toshiyuki Gogami Yun-Cheng Han Osamu Hashimoto Kentaro Hirose Ryotaro Honda Kenji Hosomi Alan Iguchi Takatsugu Ishikawa Yusuke Kaneko Masashi Kaneta Yuma Kasai Daisuke Kawama Taito Kawasaki Chigusa Kimura Shogo Kiyokawa Takeshi Koike Kazushige Maeda Tomofumi Maruta Nayuta Maruyama Masao Matsubara Koji Miwa Yohei Miyagi Sho Nagao Satoshi N. Nakamura Akira Okuyama Kotaku Suzuki Tadaaki Tamae Hirokazu Tamura Nobuhiro Terada Kyo Tsukada Tie-Shang Wang Fumiya Yamamoto Takeshi O. Yamamoto Hirohito Yamazaki 《Few-Body Systems》2013,54(7-10):1175-1178
Photoproduction of the neutral kaon on the deuteron has been investigated at the Research Center for Electron Photon Science, Tohoku University. We constructed the Neutral Kaon Spectrometer-2 for the detection of charged particles from the decay of the neutral kaon and the hyperon. We obtained a momentum distribution of K 0 with the inclusive measurement. It was consistent with the previous measurement. The total cross section of γ + d → K 0 + Λ + p was estimated from the measured integral cross section of γ + d → Λ + X. The total cross section with respect to the photon energy was compared with the theoretical calculations. It favored the Saclay-Lyon A model calculation with the ratio of the neutral to charged coupling constants of the axial-vector meson, K 1, as ~ ?1.5. The energy dependence and the magnitude of the total cross section were similar to the total cross section of γ + p → K + Λ. 相似文献
76.
Yutaka Koike 《Journal of Macromolecular Science: Physics》2013,52(1):13-37
The uniaxial deformation behavior of three polypropylene films with isotacticity indices varying from 43 to 95 was investigated in the partially molten state using real time, true stress, true strain, and birefringence measurement system. These polymers generally exhibit three regime stress‐birefringence behaviors during stretching. The unmelted crystalline regions act as physical junctions. If the films contain crystallinity that is too low (less than ca. 10%) the Regime I disappears. Under these conditions, the films were found to exhibit large linearity in strain and stress optical behavior. If, however, too low a deformation rate is employed, these relationships become non‐linear. The increase of isotacticity increases the magnitude of the birefringence at all deformation levels primarily as a result of the increase in crystallinity that helps in establishing a long‐range physical network. This increase in the long‐range connectivity was found to promote not only the orientation in crystalline domains but also in the amorphous domains. The increased long‐range connectivity in high isotacticity films was also found to result in destruction of local initial structures that generate a large fraction of the oriented amorphous chain regions. This translates into larger stress decrease and birefringence increase changes during the holding stage where the oriented amorphous chains undergo complex relaxation/oriented crystallization processes. 相似文献
77.
Y. Tanabe T. Adachi H. Sato T. Sasaki Y. Koike 《Journal of Physics and Chemistry of Solids》2008,69(12):3217-3220
We have measured the temperature dependence of the magnetic susceptibility, χ vs. T, and the magnetization curve, M vs. H, for NbSe2 single crystals, in order to compare the superconducting (SC) state in the overdoped regime of La2−xSrxCuO4 (LSCO) with the SC state of the layered conventional superconductor NbSe2. While a plateau in χ vs. T in a moderate magnetic field and a so-called second peak in M vs. H, which is due to the marked enhancement of vortex pinning, have been observed in the overdoped regime of LSCO, these behaviors have not been observed in NbSe2. The present results indicate that the anomalously marked enhancement of vortex pinning is a characteristic feature in the overdoped LSCO where a microscopic phase separation into SC and normal-state regions takes place. 相似文献
78.
N. Fujita N. Inaba F. Kirino S. Igarashi K. Koike H. Kato 《Journal of magnetism and magnetic materials》2008
Gilbert's damping constants, α, of Co(tCo)/Pt (1.4 nm) multilayer thin films are investigated by Q-band FMR analysis. α is calculated from the resonance width of the FMR spectrum. With decreasing tCo, the α value decreases from 0.034 (tCo=8.7 nm) to 0.023 (tCo=1.8 nm), and then increases to 0.037 (tCo=1.0 nm). The decrease of α with tCo>1.8 nm is probably due to the eddy current loss effects. The increase of α with tCo<1.8 nm would be caused by the increase of the distortion between the Co and the Pt layers at the interface. When the magnetic field direction was changed from θ=90° (parallel to the specimen) to θ=0° (perpendicular to the specimen), the α of all the specimens increased, and a sharp step in α was observed around θ=40°, where the α has the maximum value. 相似文献
79.
While most other glasses exhibit non-exponential structural relaxation characteristics even when the change of fictive temperature is small, a high purity silica glass exhibited exponential structural relaxation. This was demonstrated by showing that the non-exponential exponent or β value of the KWW function of the high purity silica glass approaches unity when the change of the fictive temperature approaches zero both from higher and lower temperature sides of the heat-treatment temperature. The non-exponentiality of the structural relaxation of this glass when fictive temperature change is finite is due to the change of relaxation time during the structural relaxation. 相似文献
80.
Shigeaki Koike Takahiro Kosugi Makoto Naito 《Journal of Mathematical Analysis and Applications》2018,457(1):436-460
The rate of convergence of approximate solutions via penalization for free boundary problems are concerned. A key observation is to obtain global bounds of penalized terms which give necessary estimates on integrations by the nonlinear adjoint method by L.C. Evans. 相似文献