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151.
Hideo Kojima Kazuyoshi Ozaki Noboru Matsumura Hiroo Inoue 《Journal of heterocyclic chemistry》1990,27(6):1845-1846
7-Substituted 2,3-bis(isopropylthio)naphth[1,8-bc]azepines 3a-c were synthesized in good yields by the reactions of 5-substituted 1-naphthylamines 2a-c with tris(isopropylthio)cyclopropenylium perchlorate ( 1 ) in acetonitrile under reflux. This reaction proceeds through the facile ring opening of 1 , followed by the intermediary formation of iminium salts 5a-c and then intramolecular cyclization. 相似文献
152.
E. Torikai K. Nishiyama K. Kojima K. Nagamine H. Kitazawa I. Tanaka H. Kojima 《Hyperfine Interactions》1993,79(1-4):879-883
In order to investigate the electronic structure around oxygen in superconducting La2–x
Sr
x
CuO4 (x=0.10 and 0.14), precise measurements were carried out on the paramagnetic Knight shifts in the spin rotation frequency of the negative muon bound to the oxygen with reference to antiferromagnetic La2–x
Sr
x
CuO4 (x=0.05). Remarkable temperature as well as crystalline-axis dependence was observed for the highT
c case with a divergence character towardsT
c. Possible mechanisms to explain the observed results are given. 相似文献
153.
Norimichi Tsumura Daisuke Kawazoe Toshiya Nakaguchi Nobutoshi Ojima Yoichi Miyake 《Optical Review》2008,15(6):292-294
A simple regression-based model of skin diffuse reflectance is developed based on reflectance samples calculated by Monte
Carlo simulation of light transport in a two-layered skin model. This reflectance model includes the values of spectral reflectance
in the visible spectra for Japanese women. The modified Lambert Beer law holds in the proposed model with a modified mean
free path length in non-linear density space. The averaged RMS and maximum errors of the proposed model were 1.1 and 3.1%,
respectively, in the above range. 相似文献
154.
Takakazu Kojima Takuzo Kurotu Ken-Ichi Masuda Yoshinobu Hosaka 《Journal of polymer science. Part A, Polymer chemistry》1985,23(2):343-349
The thermal decomposition of poly(sec-amyl methacrylate) is studied by simultaneous thermogravimetry–gas chromatography–mass spectrometry and by pyrolysis–gas chromatography. The TG curve has four distinct breaks and a plateau. Results of the identification of the evolved gas at the individual breaks by GC–MS techniques lead to the conclusion that these breaks correspond to the individual processes in the decomposition mechanism like that of poly(tert-butyl methacrylate): the first break, the depolymerization initiated at the unsaturated chain ends; the second break, the depolymerization initiated at the saturated chain ends; the third break, the ester decomposition; the plateau, the inhibition of decomposition by the formation of poly(methacrylic anhydride); the fourth break, the decomposition of poly(methacrylic anhydride). The extent of ester decomposition is related to the substituent constants based on Hammett equation. The ester decomposition product is separated into three pentene isomers by pyrolysis–gas chromatography: trans-2-pentene, cis-2-pentene, and 1-pentene. As raising decomposition temperature, the composition ratio of trans-2-pentene decreases and becomes constant above 620 K, and the composition ratios of cis-2-pentene and 1-pentene increase and also become constant above 620 K. These results are accounted for by mobility of atoms included in the substituent at forming a ring transition state. 相似文献
155.
Ikeda K. Kojima N. Ono Y. Kobayashi Y. Seto M. Liu X. J. Moritomo Y. 《Hyperfine Interactions》2004,156(1-4):311-314
Hyperfine Interactions - Cs2[AuIX2][AuIIIX4] (X=Cl, Br, I) is known for a perovskite-type gold mixed-valence system. We have synthesized new gold mixed valence complexes, Cs2[AuIX2][AuIIIY4] (X,... 相似文献
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