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91.
A fundamental research is carried out into convergence and stability properties of IMEX (implicit–explicit) Runge–Kutta schemes applied to reaction–diffusion equations. It is shown that a fully discrete scheme converges if it satisfies certain conditions using a technique of the B-convergence analysis, developed by Burrage, Hundsdorfer and Verwer in 1986. Stability of the schemes is also examined on the basis of a scalar test equation, proposed by Frank, Hundsdorfer and Verwer in 1997. 相似文献
92.
Toshiyuki Sugawa 《Transactions of the American Mathematical Society》2001,353(9):3603-3615
In this note, we show, in a quantitative fashion, that the limit set of a non-elementary Kleinian group is uniformly perfect if the quotient orbifold is of Lehner type, i.e., if the space of integrable holomorphic quadratic differentials on it is continuously contained in the space of (hyperbolically) bounded ones. This result covers the known case when the group is analytically finite. As applications, we present estimates of the Hausdorff dimension of the limit set and the translation lengths in the region of discontinuity for such a Kleinian group. Several examples will also be given.
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Ling-yan Li Hui Gu Yong-jun Tian Toshiyuki Nishimura Joachim Bill 《Journal of Non》2009,355(48-49):2390-2395
Inner pore channels were commonly found in precursor-derived Si–C–N ceramics. After annealing in air at 1420 °C, their oxidation structures were investigated by analytical TEM. A carbon-rich ring was frequently observed under the silica layer inside the pore channels, which consisted of graphite-like clusters in size of 20–30 nm. Origin of such interfacial structure is due to the excessive free-carbon in the amorphous Si–C–N matrix that had survived the oxidation process. This graphitic interface could further improve the oxidation resistance of the SiO2 over-layer. This novel interfacial structure was also found by annealing in N2, reaffirming the effect of composition of Si–C–N matrix. 相似文献
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Takayuki Ikehara Hideo Kurihara Toshiyuki Kataoka 《Journal of Polymer Science.Polymer Physics》2009,47(5):539-547
The effects of the lamellar growth direction, extinction rings, and spherulitic boundaries of poly(butylene succinate) (PBSU) on the spherulitic growth of poly(ethylene oxide) (PEO) were investigated in miscible blends of the two crystalline polymers. In the crystallization process from a homogeneous melt, PBSU first developed volume‐filling spherulites, and then PEO spherulites nucleated and grew inside the PBSU spherulites. The lamellar growth direction of PEO was identical with that of PBSU even when the PBSU content was about 5 wt %. PEO, which intrinsically does not exhibit banded spherulites, showed apparent extinction rings inside the banded spherulites of PBSU. The growth rate of a PEO spherulite, GPEO, was influenced not only by the blend composition and the crystallization temperature of PEO, but also by the growth direction with respect to PBSU lamellae, the boundaries of PBSU spherulites, and the crystallization temperature of PBSU, TPBSU. The value of GPEO first increased with decreasing TPBSU when a PEO spherulite grew inside a single PBSU spherulite. Then, GPEO decreased when TPBSU was further decreased and a PEO spherulite grew through many tiny PBSU spherulites. This behavior was discussed based on the aforementioned factors affecting GPEO. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 539–547, 2009 相似文献
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Ryu Sato Toshiyuki Fujio Shiduko Nakajo Satoshi Ogawa Ashraful Alam 《Tetrahedron letters》2007,48(17):3013-3016
The synthesis of benzopentathiepin having a hydroxyl group at the neighboring position of polysulfur ring was performed by demethylation of 6-ethyl-9-methoxybenzopentathiepin with hydrogenbromide. Benzotrithiole having hydroxyl group was not isolated at all. The hydroxyl group was also alkylated with alkyl iodide in the presence of weak base. 相似文献
100.