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221.
222.
Hisao Yanagi Mariko Endo Yoshiyuki Hayama 《Journal of Sol-Gel Science and Technology》2000,19(1-3):765-767
Photocurrent responses of sol-gel films of silica/titania doped with oxacarbocyanine dye were investigated with a sandwich-type photocell constructed with polymer electrolyte membrane and indium-tin-oxide glass electrodes. At an equilibrium and positive bias voltages, a typical photocell exhibited negative and positive current peaks when the visible light illumination was on and off, respectively. The wavelength dependence of the photocurrent responses well matched to the absorption band of the doped dye. This differential photocurrent response was attributed to trapping of carriers photoexcited in the dye molecules at the defect states in the matrix film. At negative bias voltages, on the other hand, the cell exhibited constant, negative photoelectrochemical currents under illumination. These differential and linear photocurrent responses were affected by the SiO2/TiO2 matrix structures depending on the Si : Ti ratio. 相似文献
223.
Masato Goto Yoshiyuki Kani Masanobu Tsuchimoto Shigeru Ohba Hideaki Matsushima Tadashi Tokii 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):7-11
In the crystals of the five title compounds, tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(ethanol‐O)dicopper(II)–ethanol (1/2), [Cu2(C6H11O2)4(C2H6O)2]·2C2H6O, (I), tetrakis(μ‐3,3‐dimethylbutyrato‐O:O′)bis(2‐methylpyridine‐N)dicopper(II), [Cu2(C6H11O2)4(C6H7N)2], (II), tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(3‐methylpyridine‐N)di‐copper(II), [Cu2(C6H11O2)4(C6H7N)2], (III), tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(4‐methylpyridine‐N)di‐copper(II), [Cu2(C6H11O2)4(C6H7N)2], (IV), and tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(3,3‐dimethylbutyric acid‐O)dicopper(II), [Cu2(C6H11O2)4(C6H12O2)2], (V), the dinuclear CuII complexes all have centrosymmetric cage structures and (IV) has two independent molecules. The Cu?Cu separations are: (I) 2.602 (3) Å, (II) 2.666 (3) Å, (III) 2.640 (2) Å, (IV) 2.638 (4) Å and (V) 2.599 (1) Å. 相似文献
224.
Hiroo Nakagawa Yoshiyuki Kani Masanobu Tsuchimoto Shigeru Ohba Hideaki Matsushima Tadashi Tokii 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):12-16
In the crystals of bis(pyridine‐N)tetrakis(μ‐trimethylsilylacetato‐O:O′)dicopper(II), [Cu2(C5H11O2Si)4(C5H5N)2], (I), the dinuclear CuII complexes have cage structures with Cu?Cu distances of 2.632 (1) and 2.635 (1) Å. In the crystals of bis(2‐methylpyridine‐N)tetrakis(μ‐trimethylsilylacetato‐O:O′)dicopper(II), [Cu2(C5H11O2Si)4(C6H7N)2], (II), bis(3‐methylpyridine‐N)tetrakis(μ‐trimethylsilylacetato‐O:O′)dicopper(II), [Cu2(C5H11O2Si)4(C6H7N)2], (III), and bis(quinoline‐N)tetrakis(μ‐trimethylsilylacetato‐O:O′)dicopper(II), [Cu2(C5H11O2Si)4(C9H7N)2], (IV), the centrosymmetric dinuclear CuII complexes have a cage structure with Cu?Cu distances of 2.664 (1), 2.638 (3) and 2.665 (1) Å, respectively. In the crystals of catena‐poly[tetrakis(μ‐trimethylsilylacetato‐O:O′)dicopper(II)], [Cu2(C5H11O2Si)4]n, (V), the dinuclear CuII units of a cage structure are linked by the cyclic Cu—O bonds at the apical positions to form a linear chain by use of a glide translation. 相似文献
225.
A chronological review is given of typical contributions which played a role in approaching quantitative predictions of phase equilibria in binary and quasibinary polymer solutions. It describes step by step findings of the variables which govern phase separations in these systems. These variables are temperature, overall polymer concentration, and chain length distribution of the polymer mixture making up the solution. The last variable gives rise to a considerable difficulty in formulating the free energy of quasibinary solutions. 相似文献
226.
Yoshiyuki Kawase Seiji Yamaguchi Osamu Maeda Akemi Hayashi Ichihiro Hayashi Kazuko Tabata Masako Kondo 《Journal of heterocyclic chemistry》1979,16(3):487-491
Benzofuro[2,3-b]quinoline ( Ia ) and its 11-methyl derivative ( Ib ) were synthesized by demethylcyclization of 3-(o-methoxyphenyl)-1,2-dihydroquinolin-2-ones (VIa,b). Benzofuro[2,3-b]quinoline-11-carboxylic acid (Id) was synthesized by chlorination followed by the action of potassium hydroxide of a lactone (IX) prepared by demethyl-cyclization of 3-(o-methoxyphenyl)-2-oxo-1,2-dihydroquinoline-4-carboxylic acid (VIII). Isomeric benzofuro[3,2-c]quinoline (Ha) and its 6-methyl derivative (IIb) were synthesized by demethyl-cyclization of 3-(o-methoxyphenyl)-1,4-dihydroquinolin-4-ones (XIa,b). Both the methyl derivatives (Ib and IIb) were converted to the carboxylic acids (Id and IId) through condensation with benzaldehyde followed by oxidation. The benzofuroquinolines (Ia,b,d and IIa,b) thus obtained were oxidized to the corresponding N-oxides (IIIa,b,d and IVa,b). 相似文献
227.
Dr. Teresa Mena‐Barragán Aya Narita Dino Matias Dr. Gustavo Tiscornia Dr. Eiji Nanba Dr. Kousaku Ohno Dr. Yoshiyuki Suzuki Dr. Katsumi Higaki Prof. José Manuel Garcia Fernández Prof. Carmen Ortiz Mellet 《Angewandte Chemie (International ed. in English)》2015,54(40):11696-11700
A general approach is reported for the design of small‐molecule competitive inhibitors of lysosomal glycosidases programmed to 1) promote correct folding of mutant enzymes at the endoplasmic reticulum, 2) facilitate trafficking, and 3) undergo dissociation and self‐inactivation at the lysosome. The strategy is based on the incorporation of an orthoester segment into iminosugar conjugates to switch the nature of the aglycone moiety from hydrophobic to hydrophilic in the pH 7 to pH 5 window, which has a dramatic effect on the enzyme binding affinity. As a proof of concept, new highly pH‐responsive glycomimetics targeting human glucocerebrosidase or α‐galactosidase with strong potential as pharmacological chaperones for Gaucher or Fabry disease, respectively, were developed. 相似文献
228.
Nobuhiro Sugihara Yoshiro Ogoma Koji Abe Yoshiyuki Kondo Toshihiro Akaike 《先进技术聚合物》1998,9(5):307-313
P-450cam (camphor-induced cytochrome P-450) was immobilized on an indium tin oxide (ITO) electrode by polypyrrole and its activity was controlled electrochemically. The results showed that P-450cam was immobilized on the ITO electrode without denaturing and the amount of P-450cam could be easily controlled. When, the electric potential was swept repeatedly between 0.4 and 0 V, the remarkable decrease of oxygen in the reaction mixture solution was observed only in the presence of camphor. In addition, hydroxycamphor was detected only in the same system by means of gas chromatography/mass spectroscopy. These results suggested that immobilized P-450cam catalyzed the hydroxylation of camphor by the supply of electron from the electrode. The effect of pH and ionic strength on the activity was examined, and it was found that the high activity expressed at the pH of 6.0 – 7.0 and KCl concentration of 0.1 – 0.2 M . The paper is the first report that P-450 enzyme activity could be controlled artificially. © 1998 John Wiley & Sons, Ltd. 相似文献
229.
Hiroshi Mitsumata Toshio Mori Tatsuo Maeda Yoshiyuki Kita Osamu Kohatsu 《Analytical sciences》2006,22(2):305-307
We have established a simple method for assaying the quantity of soluble bromine in the discharge tubes of an extra-high-pressure mercury discharge lamp. Each discharge tube is destroyed in 5 ml of 10 mM sodium hydroxide, and the recovered sodium hydroxide solution is analyzed by suppressed-ion chromatography using gradient elution. We have clarified that this method can assay less than 1 microg of soluble bromine in a discharge tube. 相似文献
230.
Yoshiyuki Sano 《Tetrahedron letters》2006,47(10):1631-1635
A short-step route for the preparation of droloxifene has been established via the novel three-component coupling reaction among 3-pivaloyloxybenzaldehyde, cinnamyltrimethylsilane, and β-chlorophenetole, the successive installation of the side-chain part, and the base-induced migration of the double bond. The present synthesis of tetra-substituted ethylene moieties is a widely applicable strategy for producing a variety of SERMs (selective estrogen receptor modulators) and SARMs (selective androgen receptor modulators), such as tamoxifen, raloxifene, and other compounds that can lead to new drugs. 相似文献