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181.
Hideaki Hagihara Masahide Murata Toshiya Uozumi 《Macromolecular rapid communications》2001,22(5):353-357
The copolymerization of ethylene and 5‐hexen‐1‐ol pretreated with trimethylaluminium was performed using [ethylene(1‐indenyl)(9‐fluorenyl)]zirconium dichloride/methylaluminoxane as the catalyst. The 5‐hexen‐1‐ol unit in the copolymer could be increased to about 50 mol‐% with increasing [5‐hexen‐1‐ol/ethylene[ ratio. 13C NMR analysis proved that the poly(ethylene‐co‐(5‐hexen‐1‐ol)) containing 50 mol‐% of 5‐hexen‐1‐ol units is an almost alternating copolymer. 相似文献
182.
Hideaki Oike Masakazu Washizuka Yasuyuki Tezuka 《Macromolecular rapid communications》2001,22(14):1128-1134
A novel and unusual polymer topology, i.e. a‐ring‐with‐two‐branches, has been constructed efficiently by making use of an interiorly functionalized poly(tetrahydrofuran) (poly(THF)) having two pyrrolidinium groups. The dicarboxylate counterion, i. e. terephthalate, was then introduced by an ion‐exchange reaction of the interiorly located pyrrolidinium group. Subsequent heat treatment under appropriate dilution caused an efficient polymer cyclization to produce an a‐ring‐with‐two‐branches polymer topology in high yield through the selective and quantitative ring‐opening of the pyrrolidinium groups by the dicarboxylate counterion. 相似文献
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186.
Hideaki Oike Yuka Yoshioka Shinji Kobayashi Megumi Nakashima Yasuyuki Tezuka Eric J. Goethals 《Macromolecular rapid communications》2000,21(17):1185-1190
Mono‐, bis‐, and tris(trifluoromethanesulfonate ester)s ((triflate ester)s) were prepared by the reaction of benzyl alcohol ( 1 ), 1,4‐bis(hydroxymethyl)benzene ( 2 ) and 1,3,5‐tris(hydroxymethyl)benzene ( 3 ) with trifluoromethanesulfonic anhydride in the presence of 2,6‐di‐tert‐butylpyridine. These benzylic triflate esters were applied in‐situ for the living polymerization of tetrahydrofuran (THF). The subsequent end‐capping reaction with a suitable nucleophile proceeded quantitatively to produce mono, bi‐ and, in particular, novel trifunctional telechelic poly(THF)s, respectively. 相似文献
187.
Hideaki Tanaka Takahisa Akatsuka Toru Ohe Yoshiro Ogoma Koji Abe Yoshiyuki Kondo 《先进技术聚合物》1998,9(2):150-154
A fluorescence probe, fluorescein isothiocyanate (FITC), was introduced to proteins, and the morphology of protein-adsorbed stearic acid monolayer was observed by fluorescence microscopy and Brewster angle microscopy (BAM) in order to analyze images. At a low protein concentration, the surface pressure increased as shown by a sigmoidal curve. A number of stripe patterns in the BAM images increased and the shapes became clear with increasing concentration of proteins. Simultaneously, the size of circular islands also became small, and finally disappeared. These results suggest that the very large stripe patterns in the BAM image show the assembly of both proteins and stearic acid molecules, and small circular islands show only the stearic acid molecules. © 1998 John Wiley & Sons, Ltd. 相似文献
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189.
Hideaki Ishikawa Kazuo Yamamoto Kazumi Fujima Misako Iwasawa 《International journal of quantum chemistry》1999,72(5):509-523
A powerful and accurate numerical three‐dimensional integration scheme was developed especially for molecular orbital calculations. A multicenter integral is decomposed into the sum of single‐center integrals using nuclear weight functions and calculated using Gaussian quadrature rules. The decomposed single‐center integrands show strong anisotropy. With a careful selection of the Gaussian quadrature rule according to the anisotropy, it is possible to obtain an accuracy of 13 digits with a small number of integration points for the overlap integrals, normalization integrals, and molecular integrals for the hydrogen molecule. ©1999 John Wiley & Sons, Inc. Int J Quant Chem 72: 509–523, 1999 相似文献
190.
Shinichi Shimizu Hideaki Hamada 《Angewandte Chemie (International ed. in English)》1999,38(18):2725-2727
Using a quartz glass tube as a bulk silica source under aqueous hydrothermal conditions afforded giant crystals of MFI zeolite about 3 mm in size (see photo). Similar procedures were successfully applied to bulk aluminosilicate ceramics to synthesize large crystals of other zeolites, such as ANA, JBW, CAN, and SOD. 相似文献