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71.
72.
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
73.
Geoffrey B Edwards Kaoru Yamanouchi Kozo Kuchitsu Masaaki Sugie Harutoshi Takeo Chi Matsumura Keiichiro Ogawa Yoshito Takeuchi 《Journal of Molecular Spectroscopy》1985,111(2):301-319
The microwave spectrum of 1-pyrroline has been measured from 8 to 48 GHz. The transitions have been assigned to those of the ground state and the four lowest excited states of the ring-puckering vibration of monomer, which is a five-membered ring molecule with one CN double bond. The trimer, which exists in the liquid phase, has not been detected in the gas phase. The geometrical structure of the monomer has been estimated by an ab initio calculation and the trimer by a molecular mechanics calculation. The former is consistent with the experimental rotational constants. A gas-phase infrared spectrum has also been measured, and the ring-puckering potential has been determined by an analysis of the combination bands of the ring-puckering mode and the ring-stretching modes. The potential is described using a puckering coordinate, z, as V(z) = az2 + bz4, where and ; these values are intermediate of the corresponding values for cyclopentene and 1-pyrazoline. The nuclear quadrupole coupling constants, χaa = ?4.39(10), χbb = 1.04(10), and χcc = 3.35(10) MHz, have been determined by an analysis of well-resolved hyperfine splittings. These constants have been reproduced by an ab initio calculation with a 4-31G(N1) basis set. 相似文献
74.
NMR measurement of 157Gd has been performed in zero external field in (Ce1?xGdx)Ru2 for x = 0.100and 0.119 at low temperature down to 25 mK. Zero field NMR is observed with large enhancements both of H1 and the intensity of the signal that are characteristic in ferromagnet. T1T increases rapidly with decreasing temperature, which is attributed to the appearance of the superconducting energy gap whose magnitude is estimated to be 0.066kTCforx = 0.100. The NMR intensity in the superconducting state decreases not so drastically as expected in the perfect Meissner state. These results are qualitatively the same as reported previously for x ≥ 0.105 and T ≥ 60 mK. The results suggest that the system is in the state of self-induced vortices predicted theoretically. 相似文献
75.
76.
77.
C.R. Fincher D.L. Peebles A.J. Heeger M.A. Druy Y. Matsumura A.G. MacDiarmid H. Shirakawa S. Ikeda 《Solid State Communications》1978,27(5):489-494
Optical absorption and reflection measurements have been carried out on pure and doped polyacetylene films. The absorption data are consistent with a model of (CH)X as a direct gap quasi-l d semiconductor; doping with AsF5 or iodine introduces absorption within the gap, but appears to leave the interband transition intact. The anisotropic reflectance from partially aligned films and the increased optical anisotropy upon doping provide evidence of quasi-l d behavior of the semiconducting pure polymer and the metallic doped polymer. 相似文献
78.
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
79.
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
80.