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21.
Toru Takagishi Sadatsugu Okuda Nobuhiko Kuroki Hiroshi Kozuka 《Journal of polymer science. Part A, Polymer chemistry》1985,23(8):2109-2116
Measurements have been made of the binding of divalent metal ions, Cu2+, Ni2+, Co2+, and Zn2+ ions, by polyethylenimine (PEI) and its acetyl or alkyl derivatives by the equilibriumdialysis technique. These metal ions, in particular the Cu2+ ion, exhibited tremendously remarkable binding affinity toward PEI. The extent of complexation of the polymer with the metal ions was decreased markedly by acetylation or alkylation of the polymer. PEI with no primary amine showed an appreciable decrease in its affinity for the metal ion. These results indicate the participation of the primary amine of the polymer in the formation of the complex. A cooperative binding isotherm was observed in PEI–metal ion complex formation, suggesting swelling or conformational change of the polymer induced by this coordination process. Binding of the Cu2+ ion by PEI was found to be essentially independent of temperature over the range 5–35°C. 相似文献
22.
23.
Toru Tachihara Susumu Ishizaki Yoshiko Kurobayashi Hiroshi Tamura Youichi Ikemoto Atsushi Onuma Keisuke Yoshikawa Tetsuya Yanai Takeshi Kitahara 《Helvetica chimica acta》2003,86(2):274-279
All possible stereoisomers of imine derivatives 1 – 4 , which have the characteristic roast odor of seafood, were synthesized. As a result of odor evaluation of all isomers, we found that each isomer has a different and characteristic odor of roasted seafood. 相似文献
24.
25.
Toru Takagishi Toshitsugu Hosokawa 《Journal of polymer science. Part A, Polymer chemistry》1989,27(6):1925-1933
The copolymers of N-vinyl-2-pyrrolidone and 2-dimethylaminoethyl methacrylate, 2-diethylaminoethyl methacrylate, 2-dimethylaminoethyl acrylate, or 2-dimethylaminopropyl acrylamide have been prepared. Studies were made of the binding of a “binding probe,” methyl orange, by the copolymers in aqueous solution. The first binding constants accompanying the binding were evaluated. Furthermore, the intensity of fluorescence of a hydrophobic fluorescent probe, 2-p-toluidinylnaphthalene-6-sulfonate, in the presence of these polymers was investigated. The nature and phenomena of dye binding and hydrophobic fluorescent probe binding with the polymers are discussed. 相似文献
26.
Ralf Otte Roland Fröhlich Shuichi Nakamura Takeshi Toru Dieter Hoppe 《Tetrahedron letters》2007,48(49):8636-8642
The enantio- and diastereoselective synthesis of allenyl aryl sulfides by asymmetric lithiation of 2-alkynyl (2-hetero)aryl sulfides is described. A dynamic thermodynamic resolution by selective crystallization of the intermediate lithium complexes derived from deprotonation, applying a bis(oxazoline) ligand, was achieved to give enantioselectivities up to 85% ee. Subsequent stereospecific nickel-catalyzed cross-coupling reactions with arylzinc reagents established a versatile access to threefold carbon-substituted allenes. 相似文献
27.
Yoshitsugu Arai Shū-ichi Kuwayama Yoshio Takeuchi Toru Koizumi 《Tetrahedron letters》1985,26(50):6205-6208
The Diels-Alder reaction of a novel chiral dienophile, alkyl ()-2--tolylsulfinylacrylates 1 with anthracene and cyclopentadiene showed high diastereoselectivity under the chelation controlled condition. 相似文献
28.
Separation of polar and non-polar analytes using dimethyl sulfoxide-modified subcritical water 总被引:1,自引:0,他引:1
Separations using methanol–water or acetonitrile–water mixtures at different temperatures have been well investigated in reversed-phase liquid chromatography. However, reversed-phase separation with dimethyl sulfoxide (DMSO)–water mixtures is much less studied. In this work, separations of polyhydroxybenzenes, phenol derivatives, benzene, toluene, ethylbenzene, and xylenes (BTEX), and polycyclic aromatic hydrocarbons (PAHs) with DMSO-modified subcritical water were performed at several temperatures to evaluate the effect of temperature on the elution strength of DMSO–water mixtures. The column efficiency obtained by using DMSO-modified subcritical water was also studied. Finally, the resolution of ethylbenzene and p-xylene was investigated. 相似文献
29.
Hiroshi Tanaka Toru Masuko Keisuke Homma Saburo Okajima 《Journal of polymer science. Part A, Polymer chemistry》1969,7(7):1997-2006
Polypropylene films of various isotacticities and crystallinities were stretched biaxially in one step in air at 140–152°C or polyaxially in poly(ethylene glycol) at 130–160°C, and the morphological changes were studied by electron microscopy (replica). In the initial stage of stretching, with vA = 1.4, the spherulites of one of the films used for the experiment were broken both from the centers and boundaries, and those of another film were broken mainly from the center. This difference in the deformation behavior seems to be characteristic of the film properties and independent of the method of stretching, although the factors involved are still unknown. On further stretching (vA = 22), well annealed spherulites were broken into many small blocklike fragments with unfolded fibrils running among them, particularly at the low stretching temperature (140°C), and fibrillation proceeded at the expense of the residual fragments. In the case of quenched or slightly crystallized material, the fragments were dendritic and divided into finer and finer fibrils on stretching. At elevated temperature, however, even for well annealed spherulites, the deformation behavior resembles that of the quenched material, and at a high degree of stretching the spherulites take on the fibrillar net structure in every case. In films containing a high amount of atactic fraction, radial, tangential, and boundary cracking occurred more easily, and broad fibrils were observed across the cracks. 相似文献
30.
Toru Takagishi Michihiro Shibano Yong Jin Lim 《Journal of polymer science. Part A, Polymer chemistry》1987,25(9):2585-2594
The ability of powdered Nylon 612 to bind methyl orange, ethyl orange, propyl orange, and butyl orange was investigated at 5, 15, 25 and 35°C in an aqueous solution. The amount of binding of the dye is much higher with this polyamide than with powdered Nylon 66 reported previously,1 although the former polymer has fewer amide end groups. The Van't Hoff plots of the first binding constant for the binding of butyl orange and propyl orange by powdered Nylon 612 exhibit a bell-shaped curve, whereas the plots for methyl orange and ethyl orange do not. Maximal binding occurs at approximately 15°C for propyl orange and at about 25°C for butyl orange. This is the first instance where the peculiar temperature dependence of the binding constant has been found in the binding of propyl orange, whose hydrophobicity is less than that of butyl orange. These tendencies can be accounted for in terms of increased hydrophobic of butyl orange. These tendencies can be accounted for in terms of increased hydrophobic domains in powdered Nylon 612 and enhanced hydrophobic contributions in the binding process. 相似文献