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91.
Total synthesis of codonocarpine () and its regio-isomer () utilizing a new cyclization procedure is described. 相似文献
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Eiichi Bannai 《Journal of Algebraic Combinatorics》1993,2(4):327-344
We introduce the concept of fusion algebras at algebraic level, as a purely algebraic concept for the fusion algebras which appear in conformal field theory in mathematical physics. We first discuss the connection between fusion algebras at algebraic level and character algebras, a purely algebraic concept for Bose-Mesner algebras of association schemes. Through this correspondence, we establish the condition when the matrix S of a fusion algebra at algebraic level is unitary or symmetric. We construct integral fusion algebras at algebraic level, from association schemes, in particular from group association schemes, whose matrix S is unitary and symmetric. Finally, we consider whether the modular invariance property is satisfied or not, namely whether there exists a diagonal matrix T satisfying the condition (ST)3 = S
2. We prove that this property does not hold for some integral fusion algebras at algebraic level coming from the group association scheme of certain groups of order 64, and we also prove that the (nonintegral) fusion algebra at algebraic level obtained from the Hamming association scheme H(d, q) has the modular invariance property. 相似文献
94.
Seiji Fukushima Eiichi Sano Yasuro Yamane Kouichi Genda Tsuneo Matsumura 《Fiber and Integrated Optics》1998,17(4):243-253
Serial optical interconnection is proposed for connections in a Torus asynchronous transfer mode switch. A cross-point switch was developed that operates at a bit rate of 20 Gbit/s. The switching operation was successfully performed using cascaded cross-point switches through an optical interconnection configuration consisting of commercial optoelectronics devices. The measured switching rate was 10 Gbit/s, and it was limited by the responses of the optoelectronics devices. 相似文献
95.
Francisco Eiichi Fujita 《Hyperfine Interactions》1998,111(1-4):191-199
In today's metallurgy, precision techniques, such as X-ray and electron diffraction, electron microscopy, infrared spectroscopy and electron probe micro-analyzer, are being indispensably used, and, comparing to them, Mössbauer spectroscopy is not inferior at all in usefulness, convenience and cost benefit. Actually, however, it is not yet popular among the metallurgists probably because people believe that the Mössbauer effect is a difficult physics, radioactive sources are difficult to handle, and spectral analyses are complicated. These beliefs are in fact groundless and must be dissolved for further diffusion of this useful Mössbauer technique in metals and other industries. The present introductory talk intends to help people's better understanding and no anxiety for using the Mössbauer spectroscopy by showing how it can be applied to various problems of metals and alloys from their birth to the end, that is, from the study of minerals and ores before smelting to that of corrosion and other failures. Firstly, the principle of Mössbauer spectroscopy will be explained with simplest illustrations together with simple pictures of apparatuses including the high temperature furnace and the high pressure cell. In the second will be shown typical examples of Mössbauer patterns of magnetite, carbon steel and other alloys, with indications of how to analyze the seemingly complicated spectra. Some other examples will be shown with special apparatuses easy to measure. The usefulness and convenience of Mössbauer spectroscopy will be understood again from these examples. More examples will be on amorphous alloys and other advanced materials. 相似文献
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Eiichi Nakai 《Journal of Mathematical Analysis and Applications》2006,313(2):730-737
Chang, Krantz and Stein [D.-C. Chang, S.G. Krantz, E.M. Stein, Hp theory on a smooth domain in Rn and elliptic boundary value problems, J. Funct. Anal. 114 (1993) 286-347] proved that if f∈Hp(Rn) and f vanishes outside , then f has an atomic decomposition whose atoms are contained in Ω. The purpose of this paper is to give another proof for the case n/(n+1)<p?1 and Ω a cube. Our argument provides a simple, direct construction of the desired atomic decomposition, and it works in a class of function spaces more general than the usual Hardy spaces. 相似文献
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