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91.
Pardo E Train C Gontard G Boubekeur K Fabelo O Liu H Dkhil B Lloret F Nakagawa K Tokoro H Ohkoshi S Verdaguer M 《Journal of the American Chemical Society》2011,133(39):15328-15331
A complex-as-ligand strategy to get a multifunctional molecular material led to a metal-organic framework with the formula (NH(4))(4)[MnCr(2)(ox)(6)]·4H(2)O. Single-crystal X-ray diffraction revealed that the anionic bimetallic coordination network adopts a chiral three-dimensional quartz-like architecture. It hosts ammonium cations and water molecules in functionalized channels. In addition to ferromagnetic ordering below T(C) = 3.0 K related to the host network, the material exhibits a very high proton conductivity of 1.1 × 10(-3) S cm(-1) at room temperature due to the guest molecules. 相似文献
92.
Watanuki S Matsuura K Tomura Y Okada M Okazaki T Ohta M Tsukamoto S 《Chemical & pharmaceutical bulletin》2011,59(11):1376-1385
We synthesized and evaluated inhibitory activity against T-type Ca(2+) channels for a series of 1-alkyl-N-[(1R)-1-(4-fluorophenyl)-2-methylpropyl]piperidine-4-carboxamide derivatives. Structure-activity relationship studies have revealed that the isopropyl substituent at the benzylic position plays an important role in exerting potent inhibitory activity, and the absolute configuration of the benzylic position was found to be opposite that of mibefradil, which was first launched as a new class of T-type Ca(2+) channel blocker. Oral administration of N-[(1R)-1-(4-fluorophenyl)-2-methylpropyl]-1-[2-(3-methoxyphenyl)ethyl]piperidine-4-carboxamide (17f) lowered blood pressure in spontaneously hypertensive rats without inducing reflex tachycardia, an adverse effect often caused by traditional L-type Ca(2+) channel blockers. 相似文献
93.
Imamura K Iwasaki S Maeda T Hashimoto K Ohtani B Kominami H 《Physical chemistry chemical physics : PCCP》2011,13(11):5114-5119
Photocatalytic reduction of nitrobenzenes to corresponding aminobenzenes in aqueous suspensions of titanium(IV) oxide (TiO(2)) containing hole scavengers under various conditions was examined. In photocatalytic reduction of m-nitrobenzenesulfonic acid (m-NBS) in the presence of formic acid (FA) under deaerated conditions, m-aminobenzenesulfonic acid (m-ABS) was produced almost quantitatively in acidic suspensions and high efficiency (>99%) in FA utilization as a hole scavenger was achieved. No re-oxidation of m-ABS occurred in acidic conditions both in the presence and absence of FA. The high yield of m-ABS was explained by strong ability of FA as a hole scavenger and possible repulsion of the reduced functional group (ammonium group, -NH(3)(+)) from the protonated, i.e., positively charged TiO(2) surface in acidic suspensions avoiding re-oxidation of m-ABS. Using TiO(2) samples of various physical properties, which had been synthesized by a solvothermal method and post-calcination at various temperatures, effects of physical properties of the TiO(2) samples on m-ABS yield were also investigated. A linear correlation between the amount of m-NBS adsorbed and the m-ABS yield was observed, suggesting that ability of TiO(2) for m-NBS adsorption is one of the key factors for effective photocatalytic reduction of m-NBS to m-ABS. This photocatalytic system can be applied for reduction of aminonitrobenzenes to corresponding diaminobenzenes (DAB) in the presence of oxalic acid as a hole scavenger. High yields of m-ABS and DAB were achieved even when the reactions were performed in the presence of oxygen. 相似文献
94.
BIT Numerical Mathematics - We consider a scalar function depending on a numerical solution of an initial value problem, and its second-derivative (Hessian) matrix for the initial value. The need... 相似文献
95.
Kotaro Ishiji Tomoyuki Matsuda Hiroko Tokoro Toshiaki Iwazumi Shin-ichi Ohkoshi 《Journal of Physics and Chemistry of Solids》2007,68(11):2158-2161
Cesium manganese hexacyanoferrates exhibit an interesting phenomenon of temperature-induced phase transition accompanied by a variation in the magnetic susceptibility. We observed the variation in the electronic state of Mn during the phase transition by using X-ray absorption spectroscopy. The results of the analyses showed that the content ratio of FeII-CN-MnIII and FeIII-CN-MnII systematically varied during the phase transition. However, the ratio of FeII-CN-MnII remained constant at almost all temperatures. These results suggest that the charge transfer between Fe and Mn ions in the FeIII-CN-MnII or the FeII-CN-MnIII bond produces the phase transition. 相似文献
96.
Jin-soo Hwang Shin-ichi Nakagiri 《Journal of Mathematical Analysis and Applications》2008,342(1):125-134
The parameter identification problem of constant parameters in the equation of membrane with strong viscosity is studied. The problem is formulated by a minimization of quadratic cost functionals by distributive measurements. The existence of optimal parameters and necessary optimality conditions for the parameters are proved. 相似文献
97.
98.
To meet the gradual changes in petroleum demand, in particular a reduced demand for heavy fuel oil, advanced technology for resid hydroprocessing is now extremely necessary. The catalyst technology for resid hydroprocessing in Japan, especially fixed bed type of hydrodesulfurization and hydroconversion, is reviewed in this article. 相似文献
99.
100.