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131.
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Kitagawa K Inoue A Shinokubo H Oshima K 《Angewandte Chemie (International ed. in English)》2000,39(14):2481-2483
133.
7-Ethynylcycloheptatriene (1) cleanly isomerizes to phenylallene in the presence of acid. A mechanism involving the protonation of ethynylnorcaradiene, which is in equilibrium with 1, followed by the cleavage of a three-membered ring to give an arenium ion, is proposed. The rearrangement is accelerated by a factor of 370 by introducing tert-butyl groups on C-2 and C-5, indicating the importance of the equilibrium concentration of the norcaradiene form as a rate-controlling factor. 相似文献
134.
Hisashi Shima Fumiyoshi Takano Hidenobu Muramatsu Masashi Yamazaki Hiroyuki Akinaga Akinori Kogure 《固体物理学:研究快报》2008,2(3):99-101
Kelvin probe force microscopy (KFM) and conductive atomic force microscopy (C‐AFM) together with micro X‐ray photoelectron spectroscopy (XPS) were performed for the stacking structure comprising of the transition metal oxide Co–O and metal electrode, which exhibits large reproducible resistance switching. The application of the external voltage by the C‐AFM cantilever decreases the resistance of Co–O, which well accords with the non‐polar forming process observed in the Pt/Co–O/Pt trilayer, known as the candidate of resistance random access memory (ReRAM). Furthermore, the KFM and micro XPS experimentally revealed that the local reductive reaction of Co–O possibly nucleates the defect related energy levels which dominates the current conduction in the low resistance state. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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The rhodium catalyzed isomerization of α-, β-, and γ-silylated allyl alcohols has been successfully applied to the selective synthesis of acylsilane, α-silyl ketones, and β-silyl ketones, respectively. 相似文献
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Hisashi Odani Masaki Uchikura Yukimasa Ogino Michio Kurata 《Journal of membrane science》1983,14(2):193-208
Diffusion and solution behavior of methanol vapor in two diblock copolymers, poly(2-vinylpyridine)—block—polyisoprene [P(2VPbI)] and poly(2-vinylpyridine)—block—polystyrene [P(2VPbS)], was studied by the weighing method at 25°C. The domain structure of films of both copolymers showed an alternating lamellar arrangement. Methanol is a good solvent for P2VP, but a nonsolvent for PI and PS. Methanol dissolved exclusively in the P2VP phase of the copolymers. For both copolymer systems, absorption and desorption processes of non-Fickian type were observed as characterized by a thickness anomaly. However, the magnitude of the deviations from purely Fickian behavior was small, and the integral diffusion coefficient, D?, was obtainable with reasonable accuracy. At low and medium concentrations, D? for P(2VPbI) was greater, by about one order of magnitude, than that for P2VP, while D? for P(2VPbS) was lower than that for P2VP. A similar trend was observed in plots of the permeability coefficient against the vapor pressure of methanol. The results indicate that the rubbery PI phase may facilitate the transport of penetrant molecules in the P(2VPbI) film. On the other hand, the glassy PS phase in the P(2VPbS) film merely interferes with the transport of methanol molecules. 相似文献
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