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101.
Li4Ti5O12 thin films for rechargeable lithium batteries were prepared by a sol-gel method with poly(vinylpyrrolidone). Interfacial properties of lithium insertion into Li4Ti5O12 thin film were examined by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and potentiostatic intermittent titration technique (PITT). Redox peaks in CV were very sharp even at a fast scan rate of 50 mV s−1, indicating that Li4Ti5O12 thin film had a fast electrochemical response, and that an apparent chemical diffusion coefficient of Li+ ion was estimated to be 6.8×10−11 cm2 s−1 from a dependence of peak current on sweep rates. From EIS, it can be seen that Li+ ions become more mobile at 1.55 V vs. Li/Li+, corresponding to a two-phase region, and the chemical diffusion coefficients of Li+ ion ranged from 10−10 to 10−12 cm2 s−1 at various potentials. The chemical diffusion coefficients of Li+ ion in Li4Ti5O12 were also estimated from PITT. They were in a range of 10−11-10−12 cm2 s−1. 相似文献
102.
Atsushi SugieHansoo Song Takafumi HorieNaoto Ohmura Kiyoshi KanieAtsushi Muramatsu Atsunori Mori 《Tetrahedron letters》2012,53(33):4457-4459
Synthesis of thiol-capped gold nanoparticle is carried out by mixing of a THF solution of HAuCl4·4H2O and nC12H25SH with a THF solution of triethylsilane in a flow system that consists of polytetrafluoroethylene tubing. The effect of residence time and reaction temperature on the particle size is examined. 相似文献
103.
104.
Enhancement of electronic excitation energy transfer in the colloidal crystals of colloidal silica suspensions doped with fluorescent dyes 总被引:1,自引:0,他引:1
Kiyoshi Shibata Hiroshi Kimura Akira Tsuchida Tsuneo Okubo 《Colloid and polymer science》2006,285(2):127-133
The efficiency of electronic excitation energy transfer from photo-excited rhodamine 110 (Rh110, energy donor) to rhodamine B (RhB, energy acceptor) in an exhaustively deionized colloidal silica suspension has been studied. This colloidal suspension shows Bragg reflection due to the formation of colloidal crystals and the Bragg-peak wavelength is controllable by the volume fraction of the silica spheres. When the Bragg-peak wavelength matches with the fluorescence band of Rh110, a depletion was observed in the Rh110 fluorescence spectrum. This means the fluorescence of Rh110 is partially trapped due to the Bragg reflection inside the crystal lattice. In the coexistence of RhB, the enhancement of RhB fluorescence intensity was observed. These facts clearly indicate the trapped photon energy of Rh110 is efficiently transferred to RhB within the colloidal crystals. The quantitative measurements showed that the enhancement of the transfer efficiency is 20% (or slightly more) in the present experimental conditions. 相似文献
105.
Kiyoshi Koyama Masato Nishimura 《Journal of polymer science. Part A, Polymer chemistry》1972,10(9):2601-2608
The polymerization of vinyl monomers initiated by binary initiator systems composed of a copper–amine complex type resin and organic halides has been studied. These binary systems initiated the polymerization of various vinyl monomers. A kinetic study of the polymerization of methyl methacrylate initiated by the copper–amine complex resin–CCl4 system was carried out, and it was found that the polymerization proceeds by way of a radical mechanism. This fact was also supported by the copolymerization of methyl methacrylate with styrene. The overall activation energy of the polymerization of methyl methacrylate was estimated as 8.4 kcal/mole. The activity of the initiator systems was greatly dependent upon the dissociation energy of carbon–halogen bonds in the organic halides. A possible initiation mechanism with the binary systems is proposed and discussed. 相似文献
106.
Manabu Nakazono Yasuyuki Sato Shigeo Hasegawa Norimasa Arisuda Aiko Miyamoto Kiyoshi Zaitsu 《Chromatographia》2009,70(5-6):933-937
Rapid separation of hydrophobic compounds such as bisindolylmaleimides, indolocarbazoles or fullerene C60 derivatives by ultra performance liquid chromatography was developed. Bisindolylmaleimides and indolocarbazoles were separated within 7 and 5 min, respectively. The linear ranges for the determination of bisindolylmaleimides and indolocarbazoles were 1.25?500 pmol and 0.5?50 pmol per injection (r > 0.99), respectively. Fullerene C60 derivatives were separated within 9 min, and the linear range for the determination of fullerene C60 derivatives was 0.1?10 pmol per injection (r > 0.99). 相似文献
107.
Keiji Yamamoto Kiyoshi Ikeda Leong Kwai Yin 《Journal of organometallic chemistry》1989,370(1-3):319-332
Enantioselective, homogeneous hydrogenation of 3-phenyl-3-butenoic acid (1) has extensively been examined in the presence of the rhodium(I)/4,5-bis[(diphenylphosphino)methyl]-2,2-dimethyldioxolane (DIOP) catalyst systems. Optimization of the reaction conditions was undertaken mainly by controlling effects of added tertiary amines as well as solvent polarities on the enantio-selectivity of the product. The best asymmetric yield (85.1% e.e.) was attained when the hydrogenation was carried out in the presence of triethylamine (5 mol%) in 75% aqueous methanol using a neutral rhodium-DIOP catalyst. 相似文献
108.
Akiko Ohno Nana Kawasaki Kiyoshi Fukuhara Haruhiro Okuda Teruhide Yamaguchi 《Magnetic resonance in chemistry : MRC》2010,48(2):168-172
Complete NMR analysis of oxytocin (OXT) in phosphate buffer was elucidated by one‐dimensional (1D)‐ and two‐dimensional (2D)‐NMR techniques, which involve the assignment of peptide amide NH protons and carbamoyl NH2 protons. The 1H? 15N correlation of seven amide NH protons and three carbamoyl NH2 protons were also shown by HSQC NMR of OXT without 15N enrichment. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
109.
110.
Kiyoshi Ando 《Journal of Graph Theory》2009,60(2):99-129
An edge of a 5‐connected graph is said to be contractible if the contraction of the edge results in a 5‐connected graph. Let x be a vertex of a 5‐connected graph. We prove that if there are no contractible edges whose distance from x is two or less, then either there are two triangles with x in common each of which has a distinct degree five vertex other than x, or there is a specified structure called a K4?‐configuration with center x. As a corollary, we show that if a 5‐connected graph on n vertices has no contractible edges, then it has 2n/5 vertices of degree 5. © 2008 Wiley Periodicals, Inc. J Graph Theory 60: 99–129, 2009 相似文献