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91.
The transformation of aldehydes, ketones and esters to the next higher homologous aldehydes was accomplished by utilizing electroreductive 1,2-elimination as a key step. 相似文献
92.
93.
H. Matsumura 《Optical and Quantum Electronics》1975,7(2):81-86
The acceptance angle of a graded index fibre, which corresponds to the numerical aperture, is presented. A geometrical technique is used to obtain the exact ray trajectory of the beam propagating along the fibre. The acceptance angle in a conventional multimode fibre is not influenced by the position in the fibre cross-sectional area, especially for the meridional rays. However in a graded index fibre, it is a function of position on the cross section of the fibre and of the incident angle of the beam. As the position moves into the fibre periphery, the acceptance angle decreases monotonically and approaches zero. 相似文献
94.
Kiichiro Matsumura Osamu Fukumoto 《Journal of polymer science. Part A, Polymer chemistry》1971,9(2):471-483
Propylene was polymerized by using a Ziegler-Natta type catalyst in the presence of ethylchloroaluminum acrylate, which was formed by the reaction of diethylaluminum chloride with acrylic acid. The polymer obtained contained acrylic units which were proved to be copolymerized with propylene units by solvent extraction, infrared spectrum, and NMR spectrum. The copolymer showed much improved properties compared with the polypropylene homopolymer. 相似文献
95.
96.
97.
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
98.
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
99.
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
100.
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