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991.
‘Fractal’ functions are formulated as a minimal cocycle on a topological dynamics which admits nontrivial scaling transformations.
In this paper, it is proved that if in addition it admits a continuous family of scaling transformations, then itscapacity is not ino(N
2). We define minimal cocycles with nontrivial scaling transformations coming from substitutions on a finite alphabet which
are proved to have capacityO(N), so that they admit only a discrete family of scaling transformations. We also construct one which has capacityO(N
2) and admit a continuous family of scaling transformations.
Supported by C.N.R.S.(U.R.A 225); Partially supported by the Japan Society for the Promotion of Science. 相似文献
992.
993.
A double fiber-optic Mach-Zehnder interferometer for sensing magnetic fields is devised using two polarization maintaining single-mode fibers. This sensor achieves not only highly sensitive performance but also excellent immunity from temperature disturbance. The sensitivity attains 243 deg/mT (mT=10-3N/A) for the sensing part of the 5 cm long fiber. 相似文献
994.
Masaki Narisawa Satoshi Kida Toshio Simoo Kiyohito Okamura Yasuo Kurachi 《Journal of Sol-Gel Science and Technology》1995,4(1):31-35
Precursor fibers for titanium carbide-carbon fibers were synthesized by reacting phenolic resin fibers with titanium isopropoxide (TIP). In this system, titanium oxide gel coated fiber was prepared by hydrolyzing TIP infiltrated resin fiber. The precursor fibers obtained after the hydrolysis were converted into titanium oxide-carbon fibers (TiO2-C fibers) by pyrolysis at 1273 K. The TiO2-C fibers were converted into titanium carbide-carbon fibers (TiC-C fibers) by heat treatment at 1373–1973 K. The mechanisms of the conversion from TiO2-C fibers to TiC-C fibers were characterized by TGA. 相似文献
995.
Tomihiro Nishiyama Toyokuni Fujiwara Satoshi Miyazaki Fukiko Yamada 《Journal of heterocyclic chemistry》1992,29(6):1529-1533
The reaction of N-(2-aminopropyl)-N-(2-hydroxypropyl)aniline with phosgene afforded cis and trans isomers of 4,8-dimethyl-6-phenyl-5,6,7,8-tetrahydro-4H-1,3,6-oxadiazocin-2-one. On the basis of ASIS data and Eu-shift difference, the title compounds are found to exist as boat-chair conformation in which the carbonyl carbon resides at the BC-2 position on the molecular plane. 相似文献
996.
Local density of states of quasiparticles around the magnetic impurity in superconductors are calculated on the basis of a pair potential the spatial dependence of which is determined self-consistently using negative Hubbard model. The spatial dependence of the tunneling conductance observed by Scanning tunneling spectroscopy (STS) strongly depends on the magnitude of the impurity potentials. 相似文献
997.
We prove a formula for the twining characters of certain Demazure modules, over a Borel subalgebra
\mathfrakb\mathfrak{b} of a finite dimensional complex semisimple Lie algebra
\mathfrakg\mathfrak{g}. This formula describes the twining character of the Demazure module by the w\omega-Demazure operator associated to an element of the Weyl group that is fixed by the Dynkin diagram automorphism w\omega of
\mathfrakg\mathfrak{g}. Our result is a refinement of the twining character formula for the irreducible highest weight
\mathfrakg\mathfrak{g}-modules of symmetric dominant integral highest weights, and also of the ordinary Demazure character formula. 相似文献
998.
Akira Okada Satoshi Yokojima Noriyuki Kurita Yasuo Sengoku Shigenori Tanaka 《Journal of Molecular Structure》2003,630(1-3):283-290
A theory for charge transfer between the electrode and the donor/acceptor molecule coupled through a DNA bridge in solution is developed. We explore the crossover between the coherent tunneling and the incoherent sequential transfer regimes by varying the electrode potential and discuss the effects of single-base mismatches in DNA duplex in both regimes. In the former regime a single-base mismatch in DNA duplex causes a reduction in the charge transfer rate simply by decreasing the electron tunneling matrix element, however, in the latter regime the effects are rather complicated. 相似文献
999.
Yasuyuki Kita Satoshi Matsuda Ryoko Inoguchi Jnaneshwara K. Ganesh Hiromichi Fujioka 《Tetrahedron letters》2005,46(1):89-91
The SnCl4-promoted rearrangement of 2,2,3,3-tetrasubstituted-2,3-epoxy-1-alcohol derivatives proceeded in a regio- and stereo-controlled manner to selectively give two types of rearranged products from a single isomer by changing the protecting group of the alcohol. 相似文献
1000.
Bai-Ru Zhao Xiao-Li Dong Peng-Shun Luo Min Gao Zhong-Xian Zhao Lian-Mao Peng Yong-Ming Ni Xiang-Gang Qiu Satoshi Awaji Kazuo Watanabe Fei Wu Bo Xu Li-Hua Zhao F.C. Zhang 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,25(1):19-23
We have measured the zero field and field cooled magnetization of the lightly oxygen doped Cu-rich La2CuO 4 + δ in a wide temperature range (5 K to 350 K). The data together with the evolution of the magnetic hysteresis loop suggest
that the ferromagnetism with Curie temperature of 280 K coexists with superconductivity below the transition temperature ∼
34 K. The coexistence occurs in the hole-rich clusters of size ? 150 nm, which are electronic phase separated from the hole-poor
antiferromagnetic background.
Received 17 October 2001 相似文献