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41.
42.
Hiroyuki Okamura Hiroki SakaeKeiji Kidani Naoki HirayamaNoboru Aoyagi Takumi SaitoKojiro Shimojo Hirochika NaganawaHisanori Imura 《Polyhedron》2012,31(1):748-753
The extraction constant and the two-phase stability constant (KD,Mβ3) of tris(2-thenoyltrifluoroacetonato)europium(III) between 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([C4mim][Tf2N]) as an ionic liquid and an aqueous phase were determined by considering the extraction equilibria including anionic tetrakis(2-thenoyltrifluoroacetonato)europate(III). Specific solute-solvent interactions between the neutral Eu(III) chelate and [C4mim][Tf2N] molecules were revealed from the relationships between the distribution constant of the enol form of 2-thenoyltrifluoroacetone (Htta) as a proton chelate and the distribution constant (KD,M) of the neutral Eu(III) chelate because the [C4mim][Tf2N] system gave the high KD,Mβ3 value compared with those in conventional molecular solvents such as benzene and 1,2-dichloroethane. The coordination environment of Eu3+ in the neutral Eu(III) chelate in [C4mim][Tf2N] was investigated by time-resolved laser-induced fluorescence spectroscopy and infrared absorption spectroscopy. Both methods consistently indicated that not only the Eu(III) chelate extracted but also Eu(tta)3(H2O)3 synthesized as a solid crystal were almost completely dehydrated in [C4mim][Tf2N] saturated with water. Consequently, the higher KD,M or extractability of the neutral Eu(III) chelate in the [C4mim][Tf2N] system can be ascribed to the dehydration of the Eu(III) chelate, which is caused by the specific solvation with [C4mim][Tf2N] molecules. 相似文献
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Takumi Abe Hiroyuki Takeda Yoshihisa Miwa Koji Yamada Reiko Yanada Minoru Ishikura 《Helvetica chimica acta》2010,93(2):233-241
It was shown that dichloramine‐T ( 1 ) reacted with cyclohexene in acetonitrile to give N1‐(2‐chlorocyclohexyl) amidine 2a and N‐(2‐chlorocyclohexyl)acetamide ( 3 ) via the competitive addition of acetonitrile and N‐chloro‐N‐tosylamino anion to cyclohexenechloronium ion. This reaction can be catalyzed by Cu(OAc)2, primarily affording 2a . Furthermore, the resulting 2a can be cyclized to benzimidazol 14a in good yield by treating with KOH in dioxane. 相似文献
45.
Takeo Sasaki Takumi Yoneyama Shota Hashimoto Sumie Takemura Yumiko Naka 《Journal of polymer science. Part A, Polymer chemistry》2013,51(18):3873-3880
Photoinduced depolymerization of poly(olefin sulfone)s possessing photobase generators in the side‐chain was investigated. Irradiation with UV light generated base on the side‐chains and induced depolymerization based on proton abstraction on the main‐chain. The effect of the length of the spacer chain, which connects the photobase‐generating moiety to the polymer main chain on the photoinduced depolymerization, also was investigated. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3873–3880 相似文献
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Masataka Sugimoto Takumi Koizumi Takashi Taniguchi Kiyohito Koyama Katsuhiro Saito Daigo Nonokawa Tsuyoshi Morita 《Journal of Polymer Science.Polymer Physics》2009,47(22):2226-2237
Melt rheological behaviors of hyperbranched‐polystyrene (PS) copolymerized by dendric macromonomer technique are presented. The time–temperature superposition principle was applicable to the hyperbranched‐PS. The branched‐PS showed slightly lower zero‐shear viscosity in comparison with linear PS regardless of a presence of a number of branches expected from the dendric macromonomer technique. Although the influence of use of multimethacryloyl macromonomer in the polymerization process was marginal for linear viscoelastic regime, nonlinear shear and uniaxial elongational flows showed distinct differences between linear and branched‐PS. The strain dependence of the damping function became weak as increase of macromonomer content. The branched‐PS exhibited the growing elongational viscosity function comparing with linear PS. This prominent effect on the elongational flow behavior can be explained by the molecular architecture of the branched‐PS. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2226–2237, 2009 相似文献
48.
Yusai Ito Naoki Sugimoto Takumi Akiyama Takeshi Yamazaki Kenichi Tanamoto 《Tetrahedron letters》2009,50(28):4084-11715
Cepaic acid was isolated as a novel xanthylium yellow pigment from the dried outer scales of the yellow onion Allium cepa Linne. Its structure was elucidated on the basis of ESI-MS and 2D NMR spectroscopy as a 9-carboxy-1,3,6,8-tetrahydroxyxanthylium, which suggests that cepaic acid and other yellow pigments in the dried outer skin of onion were formed by the nucleophilic reaction of phloroglucinol derived from quercetin, a flavonol in onion scales, by autoxidation to glyoxylic acid. To our knowledge, this is the first report of such a pigment in yellow onion. 相似文献
49.
A hybrid binary subtracted joint transform correlator was constructed using a Bi12SiO12 (BSO) spatial light modulator and a laser scanner. The usefulness of this system was confirmed experimentally using a large number of binary and halL-tone images as the reference patterns. 相似文献
50.
日本的教育体制大体上类似于其他国家,即小学6年,初中3年,高中3年,大学本科4年。大学本科毕业后另有2年硕士学位,再加3年博士学位的教育。当前在校学习的人数逐年增加,人均在校学习的时间也逐渐延长。到2000年已有将近一半的18岁同龄人进入大学学习。为适应上述教育情况的变化,日本政府目前开始了一个重整大学教育体制的计划。该计划将所有原来模式相同的649所大学划分为两大类,一类是研究和教学型的,另一类是教学型的。目前已有9所大学已被认定为第一类型的大学。本文介绍日本教育体制的变化以及上述重整计划的长远目标。 相似文献