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991.
Eri Yoshida 《Colloid and polymer science》2011,289(10):1127-1132
The nitroxide-mediated photo-controlled/living radical polymerization of ethyl acrylate was attained using (2RS,2′RS)-azobis(4-methoxy-2,4-dimethylvaleronitrile)
as the initiator, 4-methoxy-2,2,6,6-tetramethylpiperidine-1-oxyl as the mediator, and (4-tert-butylphenyl)diphenylsulfonium triflate as the photo-acid generator. The photopolymerization was performed in acetonitrile
at room temperature by irradiation with a high-pressure mercury lamp. The molecular weight distribution of the resulting polymer
decreased as the monomer concentration decreased. It was confirmed that the polymerization was controlled on the basis of
the linear correlations for the first-order time-conversion plots and the plots of the molecular weight vs. the reciprocal
of the initial concentration of the initiator, although the conversion–molecular weight plots did not show a completely linear
correlation. The block copolymerization with methyl methacrylate accompanied by no deactivation of the growing polymer chain
end supported the livingness of the polymerization. 相似文献
992.
The lemma given by Schmitt and Vogel is an important tool in the study of the arithmetical rank of squarefree monomial ideals.
In this paper, we give a Schmitt-Vogel type lemma for reductions as an analogous result. 相似文献
993.
Nitrogen-doped NaTaO3 was synthesized through 1-pot reaction, hydrothermal process using Ta3N5 as precursor. Changing concentration and amount of NaOH aqueous solution influenced nitrogen content in NaTaO3. Absorption edge of nitrogen-doped NaTaO3 was extended at 570 nm, and absorbance in visible light region depended on nitrogen content in NaTaO3. Anodic photocurrent measured under visible light irradiation became larger with increasing nitrogen content in NaTaO3-xNy. Under ultraviolet light irradiation (λ ≤ 400 nm), the highest anodic photocurrent was observed when nitrogen concentration was y = 0.024. It was possible to expand the wavelength range that can be effectively utilized for the photoelectrochemical reaction. 相似文献
994.
995.
The photoluminescence (PL) enhancement has been studied at room temperature using various specimen atmospheres (O2 gas, CO2 gas, CO2–H2 mixture gas, Ar–H2 mixture gas and vacuum) under 325 nm laser light irradiation on various metal oxides. Of them, the results obtained for BaTiO3 nanocrystals, SrTiO3 ones and HfO2 powder crystal are given in the present paper. Their PL were considerably increased in intensity by irradiation of 325 nm laser light in CO2 gas and CO2–H2 mixture gas. The cause of the PL intensity enhancements is discussed in the light of the exciton theory, the defect chemistry and the photocatalytic theory. The results may be applied for the utilization of greenhouse gas (CO2) and the optical sensor for CO2 gas. 相似文献
996.
997.
998.
Yuki Takemoto Prof. Dr. Hiroto Yoshida Prof. Dr. Ken Takaki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(46):14841-14844
Regio‐ and stereoselective installation of boryl and stannyl moieties into a carbon–carbon triple bond of various alkynes has been achieved based on a three‐component coupling reaction by using a diboron and a tin alkoxide with the aid of a copper(II) acetate–tricyclohexylphosphine complex, giving diverse vic‐borylstannylalkenes in a straightforward manner. Carbon–tin and carbon–boron bonds of the resulting borylstannylation product are successively transformed into carbon–carbon bonds by a Migita–Kosugi–Stille and a Suzuki–Miyaura coupling, leading to the formation of (Z)‐tamoxifen with anti‐breast cancer activity. 相似文献
999.
E. Shiratori K. Ikegami F. Yoshida 《Journal of the mechanics and physics of solids》1979,27(3):213-229
A method of analyzing plastic behavior by use of an anisotropic hardening plastic potential is proposed. The plastic potential surface in deviatoric stress space is assumed to be the same as the equi-plastic-strain surface. Stress-strain relations in combined loading and in multi-axial cyclic loading are calculated by use of the anisotropic hardening plastic potential and the normality rule of the plastic strain increment vector to the plastic potential surface, which are experimentally determined or confirmed by subjecting thinwalled tubular test specimens of brass to combined axial load, internal pressure and torsion. The calculated results agree fairly well with the experimental observations. 相似文献
1000.
Kenji Yoshida Tadayoshi Matsumoto Isao Kataoka 《International Journal of Heat and Fluid Flow》2005,26(6):883-893
Experimental studies on the turbulence modification in annular two-phase flow passing through a throat section were carried out. The turbulence modification in multi-phase flow due to the interactions between two-phases is one of the most interesting scientific issues and has attracted research attention. In this study, the gas-phase turbulence modification in annular flow due to the gas–liquid phase interaction is experimentally investigated. The annular flow passing through a throat section is under the transient state due to the changing cross sectional area of the channel and resultantly the superficial velocities of both phases are changed compared with a fully developed flow in a straight pipe. The measurements for the gas-phase turbulence were precisely performed by using a constant temperature hot-wire anemometer, and made clear the turbulence structure such as velocity profiles, fluctuation velocity profiles. The behavior of the interfacial waves in the liquid film flow such as the ripple or disturbance waves was also observed. The measurements for the liquid film thickness by the electrode needle method were also performed to measure the base film thickness, mean film thickness, maximum film thickness and wave height of the ripple or the disturbance waves. 相似文献