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101.
Masayasu Tasaka Satoshi Tamura Naoto Takemura Keisuke Morimoto 《Journal of membrane science》1982,12(2):169-182
Electroosmosis and streaming potential measurements were carried out across charged membranes made of collodion and sulfonated polystyrene. Experiments were confined to the range where linear flux/force relationships hold. Saxén's relationship holds between electroosmosis and streaming potential; for porous charged membranes these exhibit an approximate inverse proportionality to ionic mobility at the limit of low electrolyte concentration. Both tend towards zero at the limit of high electrolyte concentration. 相似文献
102.
103.
Ochiai M Takeuchi Y Katayama T Sueda T Miyamoto K 《Journal of the American Chemical Society》2005,127(35):12244-12245
Reported here for the first time is the iodobenzene-catalyzed alpha-oxidation of ketones, in which diacyloxy(phenyl)-lambda3-iodanes generated in situ act as real oxidants of ketones and m-chloroperbenzoic acid serves as a terminal oxidant. Oxidation of a ketone with m-chloroperbenzoic acid in acetic acid in the presence of a catalytic amount of iodobenzene, BF3.Et2O, and water at room temperature under argon affords an alpha-acetoxy ketone in good yield. p-Methyl- and p-chloroiodobenzene also serve as efficient catalysts in this direct oxidation. We found that when the reaction was carried out in the absence of a catalytic amount of iodobenzene, Baeyer-Villiger oxidation of a ketone took place. It is noted that use of water and BF3.Et2O is crucial to the success of this alpha-acetoxylation. 相似文献
104.
Kawasaki I Tsunoda K Tsuji T Yamaguchi T Shibuta H Uchida N Yamashita M Ohta S 《Chemical communications (Cambridge, England)》2005,(16):2134-2136
A novel task-specific ionic ligand with an imidazolium salt moiety was synthesized, and its catalytic ability and recyclability for asymmetric transfer hydrogenation of acetophenone derivatives with a formic acid-triethylamine azeotropic mixture in an ionic liquid [bmim][PF6] was examined. 相似文献
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106.
The pressure-volume relation of rubidium metal is studied by high-pressure x-ray diffraction up to 110 kbar at room temperature. In addition, pressure scans of the near-infrared reflectivity are recorded up to 250 kbar. Rubidium undergoes a bcc to fcc structural transition (Rb I → Rb II) at 70 ± 2 kbar. Other phase transitions occur at 128 ± 3, 160 ± 5 and 190 ± 5 kbar on the ruby pressure scale. The pressure-volume relation and the near-infrared reflectivity provide evidence for a pressure-induced 5s → 4d electronic transition similar to the well-known 6s → 5d transition in cesium metal. 相似文献
107.
Masanao Oya Tomoko Takahashi Ryoichi Katakai 《Journal of polymer science. Part A, Polymer chemistry》1976,14(8):2065-2069
4-Isobutyloxazolidinedione, L -leucine N-carboxy anhydride, was polymerized to produce high molecular weight polymer with triethylamine in n-hexane which is not a solvent for the N-carboxy anhydride and poly-L -leucine. It was found that as the crystal size became smaller, the total surface area was increased, the initial rate of polymerization was increased, and inherent viscosity of the formed polymer was decreased. 相似文献
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