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61.
62.
Yoshiro Masuyama Kazuki YoshikawaNoriyuki Suzuki Kenji HaraAtsushi Fukuoka 《Tetrahedron letters》2011,52(51):6916-6918
Copper(II)-exchanged hydroxyapatite, prepared by ion-exchanging of Ca(II) in calcium hydroxyapatite [Ca10(PO4)6(OH)2] with Cu(NO3)2 at 70 °C in water, functions as a reusable heterogeneous catalyst with neither reducing agents nor bases for azide-alkyne [3+2] cycloaddition at 50 °C in water under air. 相似文献
63.
Kazuki Abe Noriko Ogawa Hiromasa Nagase Tomohiro Endo Haruhisa Ueda 《Journal of inclusion phenomena and macrocyclic chemistry》2011,70(3-4):385-388
Although phase-solubility studies have often been used to evaluate the interaction of cyclodextrins (CDs) with various drugs, hundreds of milligrams of both CD and drug are required to prepare a phase diagram. A method that would require considerably less material for evaluating complex formation between a CD and guest compound is therefore needed. We previously reported the detection of the interactions between ??-CD and various drugs using a Biacore® system. In this study, we succeeded in immobilizing 6-monodeoxy-6-monoamino-??-CD on the gold surface of a sensor chip and in detecting the interactions between the immobilized ??-CD and various drugs. The interaction processes were kinetically analyzed using Biacore®. The surface plasmon resonance sensorgrams indicated that the association and dissociation rates of the interactions between ??-CD and drugs were faster than those between ??-CD and drugs. Although the association constants calculated from the sensorgrams were smaller than those calculated from phase-solubility studies, good correlation was shown between these data. 相似文献
64.
A new direct conversion of O,O-acetals to esters via O,P-acetal intermediates was developed. The regioselective cleavage of unsymmetrical cyclic acetals occurred to give the more crowded esters as single isomers. 相似文献
65.
Bulky tertiary amines, especially dicyclohexylisobutylamine, smoothly reduced α,β-unsaturated ketones in the presence of trichlorosilyl triflate to give the corresponding saturated ketones in excellent yields. Isotope-labeling studies revealed that an α-hydrogen of the amine was transferred to the enones during reduction. 相似文献
66.
Nakamura K Kanazawa K Kobayashi N 《Chemical communications (Cambridge, England)》2011,47(36):10064-10066
We have demonstrated electroswitchable emission and coloration using a novel composite material containing luminescent europium(III) complex Eu(hfa)(3)(H(2)O)(2) and diheptyl viologen HV(2+). The photoluminescence of the Eu(III) complex was controlled by the electrochemical coloration of HV(2+)via intermolecular energy transfer mechanisms. 相似文献
67.
H. Fuchigami Y. Nakao S. Tanimura Y. Uehara T. Kurata S. Tsunoda H. Niino A. Yabe 《Applied Physics A: Materials Science & Processing》1998,67(3):277-282
Received: 12 March 1998/Accepted: 15 March 1998 相似文献
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70.
Naoshi Kusumoto Kazuki Matsumoto Motowo Takayanagi 《Journal of polymer science. Part A, Polymer chemistry》1969,7(7):1773-1787
Bulk-crystallized isotactic polypropylene samples with different crystalline textures were etched by fuming nitric acid to remove the disordered region. The radicals produced by irradiation of γ-rays or ultraviolet light on these etched samples in vacuum at liquid nitrogen temperature were investigated by the ESR method. A triplet spectrum in addition to the original spectrum of polypropylene radicals was separated for the etched samples. It was concluded that this triplet was caused by radical species associated with nitro groups introduced on the surface of the crystalline residues by etching. The difference in the intensity of this triplet among the samples was ascribed to differences in crystalline textures and interpreted in a quantitative way. The concentration of polypropylene radicals corrected for the triplet differed among the quenched, annealed, and cold-drawn samples and the sample annealed one after drawing. This fact was interpreted on the basis of the hypothesis that radical sites were almost concentrated in the defects of crystal domain. The well known nonet spectrum, which can be observed at liquid nitrogen temperature after annealing the irradiated samples at room temperature, was also confirmed to be attributable to the defects of crystals. The behavior of free methyl radicals induced by ultraviolet irradiation was also found to be strongly dependent on the state of aggregation of the polymer molecules. 相似文献