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81.
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83.
Microwave spectrum of monodeuterated diacetylene (HCCCCD), which is nonpolar in the equilibrium configuration, was observed in various excited states of bending vibrations. Dipole moments in the ν6, 2ν6, and ν6 + ν9 vibrational states were determined from the Stark effect measurement to be 0.0907(6), 0.1681(14), and 0.0900(4) D with uncertainties in parentheses, where ν6 and ν9 denote respectively the CCH bending and lowest frequency bending vibrations. The l-type doubling constant in the ν6 state is 2.1316(28) MHz. Rotational constants were determined in MHz; ν6(Π), 4086.2165(44); 2ν6(Δ), 4087.6963(58); ν6 + ν9(Δ), 4097.7537(50); 2ν8(Δ), 4094.4786(103); ν6 + ν7(Δ), 4092.9074(176); ν7 + ν8(Δ), 4095.8925(354); 2ν6 + ν9(Φ), 4098.9505(339). 相似文献
84.
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
85.
Tatsuya Shono Yoshihiro Matsumura Kenji Tsubata Yoshihiro Sugihara 《Tetrahedron letters》1982,23(11):1201-1204
A new method to introduce an acyl or a formyl group to β-position of aliphatic amines was studied using encarbamates, prepared from α-methoxycarbamates, as key intermidiates. 相似文献
86.
87.
In this paper, we give a sufficient condition for a graph to have a degree bounded spanning tree. Let n ≥ 1, k ≥ 3, c ≥ 0 and G be an n-connected graph. Suppose that for every independent set ${S \subseteq V(G)}In this paper, we give a sufficient condition for a graph to have a degree bounded spanning tree. Let n ≥ 1, k ≥ 3, c ≥ 0 and G be an n-connected graph. Suppose that for every independent set S í V(G){S \subseteq V(G)} of cardinality n(k−1) + c + 2, there exists a vertex set X í S{X \subseteq S} of cardinality k such that the degree sum of vertices in X is at least |V(G)| − c −1. Then G has a spanning tree T with maximum degree at most k+éc/nù{k+\lceil c/n\rceil} and ?v ? V(T)max{dT(v)-k,0} £ c{\sum_{v\in V(T)}\max\{d_T(v)-k,0\}\leq c} . 相似文献
88.
S. Misaki S. Takamatsu M. Suefuji T. Mitote M. Matsumura 《Molecular Crystals and Liquid Crystals》2013,570(1):123-132
A new series of fluorine containing phenyl benzoates has been synthesized and the transition temperatures of these compounds have been determined. A series of 4-trifluoromethylphe 4nyl 4-n-alkybenzoates showed no liquid crystalline behaviour, but the 4-trifluoromethylphenyl 4-n-alkoxybenzoates series, with six carbons or more in alkoxy chain, was mesomorphic. The 4-cyanophenyl 4-perfluoroalkylbenzoates showed smectic liquid crystalline properties. 相似文献
89.
Detailed studies on the dependence of the ECB effect on the applied frequency have been made in a nematic liquid crystal MBBA. It is found experimentally that, when the applied voltage is just above the threshold voltage, there are strong dependences of both the delay time and the mean deformation angle of the molecular director subjected to a constant voltage setup on the applied frequency. Those applied frequency dependences of the ECB effect can be interpreted in terms of the dielectric alignment in an electrically conducting nematic liquid crystal. We have measured the capacitance of the deformed liquid crystal cell varying the applied frequency. The experimental results are compared with the Gruler and Cheung theoretical prediction, and good agreements are obtained between them when the applied voltage is just above the threshold voltage. 相似文献
90.
Abstract Electronic states in junctions of nanotubes with different circumferences are studied in an effective-mass approximation. The junction is characterized by boundary conditions which mix wave functions associated with K and K′ points. At ε=0, they decay linearly with the distance from the thicker nanotube, showing that the conductance decays with the junction length in proportion to its third power. 相似文献