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801.
A three-dimensional lattice of the Josephson junctions with a finite self-conductance is employed to model ceramic superconductors. By using Monte Carlo simulations it is shown that the aging disappears in the strong screening limit. In the weak screening regime, aging is present even at low temperatures. For intermediate values of the self-inductance, aging occurs in an intermediate temperature interval but is suppressed entirely at high and low temperatures. Our results are in good agreement with experiments. 相似文献
802.
Minami T Okamoto H Ikeda S Tanaka R Ozawa F Yoshifuji M 《Angewandte Chemie (International ed. in English)》2001,40(23):4501-4503
803.
804.
Beverly L. Brechner Kazuhiro Kawamura 《Proceedings of the American Mathematical Society》2001,129(2):617-620
We prove that the homeomorphism group of each one of a collection of continua constructed in a paper by the first author (Trans. Amer. Math. Soc. 121 (1966), 516-548) is one dimensional. This answers a question posed in that paper.
805.
Ghalib R. M. Mehdi S. H. Malla A. M. Alam M. G. Hashim R. Novaković S. B. Kawamura F. Alzahrani H. A. H. 《Crystallography Reports》2021,66(7):1279-1285
Crystallography Reports - A heterocyclic molecule of a novel class with a multiple ring system has been synthesized using a new and simple strategy and acetic acid as catalyst. The structure of the... 相似文献
806.
Matsubara M. Teramoto S. Nagatani A. Kawamura S. Tsujiuchi N. Ito A. Kobayashi M. Furuta S. 《Experimental Techniques》2021,45(1):37-47
Experimental Techniques - Nonlinear damping with respect to vibration amplitude is particularly important in mechanical dynamics. The addition of short fibers to damping materials is considered to... 相似文献
807.
Kawamura I Degawa Y Yamaguchi S Nishimura K Tuzi S Saitô H Naito A 《Photochemistry and photobiology》2007,83(2):346-350
Bacteriorhodopsin (bR) is a retinal protein in purple membrane of Halobacterium salinarum, which functions as a light-driven proton pump. We have detected pressure-induced isomerization of retinal in bR by analyzing 15N cross polarization-magic angle spinning (CP-MAS) NMR spectra of [zeta-15N]Lys-labeled bR. In the 15N-NMR spectra, both all-trans and 13-cis retinal configurations have been observed in the Lys N(zeta) in protonated Schiff base at 148.0 and 155.0 ppm, respectively, at the MAS frequency of 4 kHz in the dark. When the MAS frequency was increased up to 12 kHz corresponding to the sample pressure of 63 bar, the 15N-NMR signals of [zeta-15N]Lys in Schiff base of retinal were broadened. On the other hand, other [zeta-15N]Lys did not show broadening. Subsequently, the increased signal intensity of [zeta-15N]Lys in Schiff base of 13-cis retinal at 155.0 ppm was observed when the MAS frequency was decreased from 12 to 4 kHz. These results showed that the equilibrium constant of [all-trans-bR]/[13-cis-bR] in retinal decreased by the pressure of 63 bar. It was also revealed that the structural changes induced by the pressure occurred in the vicinity of retinal. Therefore, microscopically, hydrogen-bond network around retinal would be disrupted or distorted by a constantly applied pressure. It is, therefore, clearly demonstrated that increased pressure induced by fast MAS frequencies generated isomerization of retinal from all-trans to 13-cis state in the membrane protein bR. 相似文献
808.
Surface diffusion during decay of a two-dimensional nano-island formed on Si(1 0 0) surface at 750-800 K is studied using STM and a kinetic Monte Carlo simulation. From a surface diffusion point of view, decay proceeds so that the total diffusion rate of atoms on a surface decreases. Atoms at step edges move more frequently than terrace atoms, which results in decay from step edges of the island. In addition, a terrace atom takes part in surface diffusion in the same way as an atom from steps of the island once it hops up on a terrace leaving a vacancy. The mass transport is not a specific atom process but terrace atoms and vacancies on the terrace are involved. Repeated upward and downward hops of atoms and their difference are combined with surface diffusion, which leads to the mass transport. Some tracks of atom using simulation show random walk with preferential diffusion along step edges, re-entering to the island, exchange of diffusing atom and filling in a vacancy on the terrace. The motion of the center of the island to the upper side of the terrace observed by STM is also well reproduced in the simulation. 相似文献
809.
D. Kameda H. Ueno K. Asahi D. Nagae M. Takemura K. Shimada A. Yoshimi T. Nagatomo T. Sugimoto M. Uchida T. Arai K. Takase S. Suda T. Inoue J. Murata H. Kawamura H. Watanabe Y. Kobayashi M. Ishihara 《Hyperfine Interactions》2007,180(1-3):61-64
The electric quadrupole moments for the ground states of 32Al and 31Al have been measured by the β ray-detected nuclear quadrupole resonance method. Spin-polarized 32Al and 31Al nuclei were obtained from the fragmentation of 40Ar projectiles at E/A?=?95 MeV/nucleon, and were implanted in a single crystal α-Al2O3 stopper. The measured Q moment of 32Al, |Q(32Al)|?=?24(2) mb, is in good agreement with a conventional shell-model calculation with a full sd model space and empirical effective charges, while that of 31Al is considerably smaller than the sd calculations. 相似文献
810.
Spin and chirality orderings of the three-dimensional Heisenberg spin glass are studied under magnetic fields in light of the recently developed spin-chirality decoupling-recoupling scenario. It is found by Monte Carlo simulations that the chiral-glass transition and the chiral-glass ordered state, which are essentially of the same character as their zero-field counterparts, occur under magnetic fields. The implication to the experimental phase diagram is discussed. 相似文献