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61.
This is a continuation of the paper (Mizuguchi and Saito, Ann Funct Anal 2:22–33, 2011). We consider the Banach space \({X=(\mathbb{R}^2, \|\cdot\|)}\) with a normalized, absolute norm. We treat three geometric constants; the von Neumann–Jordan constant C NJ(X), the modified von Neumann–Jordan constant \({C^{\prime}_{\rm NJ}(X)}\) and the Zb?ganu constant C Z (X). We consider the conditions in which these constants coincide with their upper bound. 相似文献
62.
Kuroda M Yokosuka A Kobayashi R Jitsuno M Kando H Nosaka K Ishii H Yamori T Mimaki Y 《Chemical & pharmaceutical bulletin》2007,55(8):1240-1244
Cytotoxicity-guided fractionation of the 80% EtOH extract of Tithonia diversifolia has resulted in the isolation of twelve sesquiterpenoids (1-12), including three new ones (4, 10, 12), and three known flavonoids (13-15). The structures of the new compounds were determined by analysis of their spectroscopic data. The isolated compounds showed cytotoxic activity against HL-60 leukemia cells with IC(50) values ranging from 0.13 to 13.0 microM, when etoposide used as a positive control gave an IC(50) value of 0.43 microM. The cancer growth inhibitory property of 9, the main cytotoxic compound in T. diversifolia, was examined using a disease-oriented panel composed of 39 human cancer cell lines in the Japanese Foundation for Cancer Research. 相似文献
63.
Novel cyclodextrin rotaxanes with oligothiophene as an axis molecule have been prepared by the Suzuki coupling reaction of 6-O-(4-iodophenyl)-beta-CD (6-I-Ph-beta-CD) with di(1,3,2-dioxaborolan-2-yl)-oligothiophene (oligothiophene diboric ethylene glycol esters) in aqueous solutions of dimethyl-beta-cyclodextrin (DM-beta-CD). These reactions gave [2]rotaxanes and [3]rotaxanes, which were isolated by reversed phase chromatography. The fluorescence intensities of rotaxanes are higher than those of dumbbell-shaped molecules (without DM-beta-CD) in aqueous solutions. The inclusion ratio and chain length of rotaxanes have been found to relate to the emission properties and emission intensities of oligothiophene. In aqueous solutions, fluorescence quantum yields of rotaxanes are higher than those of dumbbell-shaped molecules. The increase in the fluorescence efficiency of rotaxane is caused by suppression of intermolecular interactions, indicating the effect of insulated oligothiophene with DM-beta-CD. beta-CD at the both ends of rotaxanes functions not only as bulky stoppers but also as the recognition site for guest molecules, as verified by fluorescence quenching experiments. 相似文献
64.
65.
Vinyl Grignard reagents reacted with cyclic ethers in the presence of a nickel catalyst giving rise to 2:1 coupling products 1 regioselectively. When chlorosilanes were used instead of cyclic ethers, 2:2 component coupling products 6 were obtained. A plausible reaction pathway via 1,3-butadiene-nickel complex and (2-butene-1,4-diyl)magnesium was proposed. 相似文献
66.
Hiroyasu Izeki 《Proceedings of the American Mathematical Society》2002,130(12):3731-3740
We give a sufficient condition for a higher dimensional Kleinian group to be convex cocompact in terms of the critical exponent of . As a consequence, we see that the fundamental group of a compact conformally flat manifold with positive scalar curvature is hyperbolic in the sense of Gromov. We give some other applications to geometry and topology of conformally flat manifolds with positive scalar curvature.
67.
T. Ishihara K. Nishida H. Nishiguchi Y. Takita K. Chaki 《Research on Chemical Intermediates》2006,32(3-4):253-262
A new reforming process was studied using Ni/SiO2 with a hydrogen-permeating membrane reactor. Nickel catalyst supported on SiO2 is highly active for CH4?H2O?O2 reaction in membrane reactor and the reaction close to CH4+0.35O2+1.3H2O→CO2+3.3H2 proceeds at 873 K. Since the selectivity to carbon and CO2 increased and decreased with decreasing contact time respectively, it is considered that the reaction was started by decomposition of CH4 followed by oxidation of C and water shift reaction. Therefore, the reaction mechanism was different from so-called autothermal reforming (ATR) reaction. 相似文献
68.
Hiroaki Kitagishi Dr. Yasuaki Kakikura Hiroyasu Yamaguchi Dr. Koji Oohora Akira Harada Prof. Dr. Takashi Hayashi Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(7):1170-1170
Supramolecular protein polymers consisting of cytochrome b562 monomers with heme covalently attached to the protein surface are presented by T. Hayashi and co‐workers in their Communication on page 1271 ff. Not only one‐dimensional hemoprotein fibers with submicrometer lengths have been prepared, but when a heme triad was added as a pivot molecule, two‐dimensional protein assembly networks resulted, which cover over 100 square micrometers.
69.
SB Choi H Furukawa HJ Nam DY Jung YH Jhon A Walton D Book M O'Keeffe OM Yaghi J Kim 《Angewandte Chemie (International ed. in English)》2012,51(35):8791-8795
Caging cages: Crystals of a metal-organic framework, MOF-123 [Zn(7) O(2) (NBD)(5) (DMF)(2) ] have a three-dimensional porous structure in which DMF ligands (see picture, pink) protrude into small channels. Removal of these ligands triggers the transformation of this MOF to the doubly interpenetrating form, MOF-246 [Zn(7) O(2) (NBD)(5) ]. Moreover, addition of DMF into MOF-246 triggers reverse transformation to give MOF-123. NBD=2-nitrobenzene-1,4-dicarboxylate. 相似文献
70.
T Ishihara H Arikawa T Akbay H Nishiguchi Y Takita 《Journal of the American Chemical Society》2001,123(2):203-209
Oxide ion conductivity in La(2)GeO(5)-based oxide was investigated and it was found that La-deficient La(2)GeO(5) exhibits oxide ion conductivity over a wide range of oxygen partial pressure. The crystal structure of La(2)GeO(5) was estimated to be monoclinic with P2(1)/c space group. Conductivity increased with increasing the amount of La deficiency and the maximum value was attained at x = 0.39 in La(2 - x)GeO(5 - delta). The oxide ion transport number in La(2)GeO(5)-based oxide was estimated to be unity by the electromotive force measurement in H(2)-O(2) and N(2)-O(2) gas concentration cells. At a temperature higher than 1000 K, the oxide ion conductivity of La(1.61)GeO(5 - delta) was almost the same as that of La(0.9)Sr(0.1)Ga(0.8)Mg(0.2)O(3 - delta) or Ce(0.85)Gd(0.15)O(2 - delta), which are well-known fast oxide ion conductors. On the other hand, a change in the activation energy for oxide ion conductivity was observed at 973 K, and at intermediate temperature, the oxide ion conductivity of La(1.61)GeO(5 - delta) became much smaller than that of these well-known fast oxide ion conductors. The change in the activation energy of the oxide ion conductivity seems to be caused by a change in the local oxygen vacancy structure. However, doping a small amount of Sr for La in La(2)GeO(5) was effective to stabilize the high-temperature crystal structure to low temperature. Consequently, doping a small amount of Sr increases the oxide ion conductivity of La(2)GeO(5)-based oxide at low temperature. 相似文献