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31.
Y. Ota M. Machida T. Koyama 《Physica C: Superconductivity and its Applications》2011,471(21-22):760-762
We construct a theory of dynamical behavior in intrinsic Josephson junction stacks with multigap superconducting layers. The theory predicts the existence of two kinds of phase modes, one of which is the Josephson-plasma mode and other of which is the Leggett’s mode. We discuss a cooperative phenomena induced by inter-band Josephson coupling in addition to capacitive and inductive couplings between the superconducting layers. 相似文献
32.
The existence of a 2‐factor in K1, n‐free graphs with large connectivity and large edge‐connectivity
R. E. L. Aldred Yoshimi Egawa Jun Fujisawa Katsuhiro Ota Akira Saito 《Journal of Graph Theory》2011,68(1):77-89
In this article, we study the existence of a 2‐factor in a K1, n‐free graph. Sumner [J London Math Soc 13 (1976), 351–359] proved that for n?4, an (n?1)‐connected K1, n‐free graph of even order has a 1‐factor. On the other hand, for every pair of integers m and n with m?n?4, there exist infinitely many (n?2)‐connected K1, n‐free graphs of even order and minimum degree at least m which have no 1‐factor. This implies that the connectivity condition of Sumner's result is sharp, and we cannot guarantee the existence of a 1‐factor by imposing a large minimum degree. On the other hand, Ota and Tokuda [J Graph Theory 22 (1996), 59–64] proved that for n?3, every K1, n‐free graph of minimum degree at least 2n?2 has a 2‐factor, regardless of its connectivity. They also gave examples showing that their minimum degree condition is sharp. But all of them have bridges. These suggest that the effects of connectivity, edge‐connectivity and minimum degree to the existence of a 2‐factor in a K1, n‐free graph are more complicated than those to the existence of a 1‐factor. In this article, we clarify these effects by giving sharp minimum degree conditions for a K1, n‐free graph with a given connectivity or edge‐connectivity to have a 2‐factor. Copyright © 2010 Wiley Periodicals, Inc. J Graph Theory 68:77‐89, 2011 相似文献
33.
Naren G Nishida I Shimada Y Tsuji Y Bai S Okaue Y Yokoyama T 《Journal of colloid and interface science》2011,353(1):331-334
This study elucidates the effect of zinc (Zn), which is an anticorrosive water additive, on the formation of silica scales from cooling water. In these experiments, the silica scales were analyzed by EPMA, and the results indicate that Zn is sorbed into the silica scales during formation. Measurements of the solubility of Zn(OH)(2) at various concentrations of silicic acid demonstrate that Zn is present as a silicato complex of Zn (SCZ) in cooling water. From adsorption experiments of the SCZ on silica and alumina, which are major components of the silica scales, it can be concluded that the SCZ accelerates the formation of silica scales from cooling water. 相似文献
34.
35.
Dynamical features of hydrogen bonds in methanol–water mixtures have been analysed in terms of lifetime in the wide range of conditions, including supercritical states, using a molecular dynamics simulation with flexible potential models. Hydrogen bond characteristics in methanol–water mixtures were investigated by considering the combination of molecular species and donor–acceptor of hydrogen-bonded molecules. The hydrogen bond lifetimes mainly depend on temperature, and those in supercritical condition were about 1/10th of that at ambient condition. Focusing on the composition dependence of the hydrogen bond lifetime, the unique behaviour of that resulting from hydration structure was observed. Moreover, the molecular combination, which showed the largest hydrogen bond lifetime, was different for ambient and high temperature and high pressure conditions. The relationship between hydrogen bond lifetime and molar volume was also calculated to discuss the hydrogen bond lifetime in terms of the collision frequency of molecules and the intermolecular distance. 相似文献
36.
The binding of phenylbutazone (PB) to bovine serum albumin (BSA) was considered to be predominantly due to hydrophobic interaction based on the thermodynamic parameters obtained by an equilibrium dialysis method. Little variation of proton nuclear magnetic resonance (1H-NMR) chemical shift of PB was found with change in the concentration of PB (0.5-5 mM) or upon the addition of BSA (7.25 x 10(-5) M). The NMR spectrum of PB in 0.1 M phosphate buffer solution at pH 7 showed that PB existed as a mesomeric anion. The spin-lattice relaxation time (T1) of PB was almost concentration-independent, but decreased in the presence of BSA to 36-38% for the phenyl group and 48-100% for the butyl group. The spin-spin relaxation time (T2) of PB was also almost independent of concentration, but was remarkably decreased in the presence of BSA to ca. 2.5% for the phenyl group and ca. 6-9% for the butyl group. The ratios of the spin-spin relaxation rate (1/T2) of the free PB to that of the bound PB were ca. 5000-11000 for the butyl group and ca. 23000 for the phenyl group. The binding of PB to BSA was considered to involve primarily the phenyl group. 相似文献
37.
N. Usami J. Arai E. S. Kim K. Ota T. Hattori Y. Shiraki 《Physica E: Low-dimensional Systems and Nanostructures》1998,2(1-4)
Two approaches to control the position and the size of semiconductor islands are proposed. The first method is to perform overgrowth on a cleaved edge of strained multiple quantum wells which acts as a substrate with a periodically modulated lattice constant, thus inducing a periodic strain to the overgrown layer. The second method is to selectively grow islands in specific windows defined by electron beam lithography. Both the methods are applied to the Ge/Si system and the controllability of the Ge island formation is demonstrated. 相似文献
38.
A graph G of order at least 2n+2 is said to be n‐extendable if G has a perfect matching and every set of n independent edges extends to a perfect matching in G. We prove that every pair of nonadjacent vertices x and y in a connected n‐extendable graph of order p satisfy degG x+degG y ≥ p ? n ? 1, then either G is hamiltonian or G is isomorphic to one of two exceptional graphs. © 2002 Wiley Periodicals, Inc. J Graph Theory 40: 75–82, 2002 相似文献
39.
40.
K Torizumi S Okamoto M Yasui Y Okamoto T Tuda K Ota F Oka H Sagawa K Yabe A Okuyama 《Radioisotopes》1988,37(11):623-626
The bone metabolic markers showed the significant differences in age and sex of the hemodialysis patients with renal insufficiency. It is likely that the evaluations of bone change and biochemical metabolic markers should be based on serum estradiol level, sex and age of the renal hemodialysis patients. 相似文献