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931.
Toshiyuki Hamada Takuya Arimura Tatsuya Sakoda 《Plasma Chemistry and Plasma Processing》2012,32(2):325-332
An optimal gas supply method for the micro discharge plasma generated along a quartz glass electrode, which was useful for
the maskless fabrication of electrode grooves for surface electrodes on solar cells, was examined. We here constructed an
electrode system with gas inlet and outlet holes. The gas supply directly to the plasma region contributed to reduce byproducts
on the surface being etched, and then it was confirmed that the uniform etching was achieved in the case where the micro-discharge
plasma locally produced at the etching area. 相似文献
932.
Prof. Dr. Shunichi Fukuzumi Takuya Mizuno Tetsuya Ojiri 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(49):15794-15804
Manganese(V)–oxo–porphyrins are produced by the electron‐transfer oxidation of manganese–porphyrins with tris(2,2′‐bipyridine)ruthenium(III) ([Ru(bpy)3]3+; 2 equiv) in acetonitrile (CH3CN) containing water. The rate constants of the electron‐transfer oxidation of manganese–porphyrins have been determined and evaluated in light of the Marcus theory of electron transfer. Addition of [Ru(bpy)3]3+ to a solution of olefins (styrene and cyclohexene) in CH3CN containing water in the presence of a catalytic amount of manganese–porphyrins afforded epoxides, diols, and aldehydes efficiently. Epoxides were converted to the corresponding diols by hydrolysis, and were further oxidized to the corresponding aldehydes. The turnover numbers vary significantly depending on the type of manganese–porphyrin used owing to the difference in their oxidation potentials and the steric bulkiness of the ligand. Ethylbenzene was also oxidized to 1‐phenylethanol using manganese–porphyrins as electron‐transfer catalysts. The oxygen source in the substrate oxygenation was confirmed to be water by using 18O‐labeled water. The rate constant of the reaction of the manganese(V)–oxo species with cyclohexene was determined directly under single‐turnover conditions by monitoring the increase in absorbance attributable to the manganese(III) species produced in the reaction with cyclohexene. It has been shown that the rate‐determining step in the catalytic electron‐transfer oxygenation of cyclohexene is electron transfer from [Ru(bpy)3]3+ to the manganese–porphyrins. 相似文献
933.
Atsushi Nakagawa Hiroshi Kamitakahara Toshiyuki Takano 《Cellulose (London, England)》2012,19(4):1315-1326
A novel synthetic method to link acetylated cellulose derivatives with methylated cellulose derivatives via Huisgen 1,3-dipolar cycloaddition was developed to produce 1,2,3-triazole-linked diblock copolymers consisting of hydrophilic cellobiose or low-molecular-weight cellulose and a hydrophobic 2,3,6-tri-O-methyl-cellulose. Huisgen 1,3-dipolar cycloaddition had the advantage over glycosylation reaction of being able to connect a hydrophilic block having higher molecular weight than cellobiose with a hydrophobic 2,3,6-tri-O-methyl-cellulose block. As a consequence, 2.0 wt% aqueous solutions of the 1,2,3-triazole-linked diblock methylcellulose analogues exhibited the thermoreversible gelation in water at around 25 °C as same as that of β-(1 → 4)-linked diblock methylcellulose. Differential scanning calorimetry measurements of 2.0 wt% aqueous solutions of the diblock copolymers revealed that an important structural factor for its thermoreversible gelation was not a β-(1 → 4)-glycosidic linkage between hydrophilic and hydrophobic blocks of diblock methylcellulose, but a sequence of anhydro 2,3,6-tri-O-methyl-glucopyranosyl units and that of unmodified glucopyranosyl ones. 相似文献
934.
The ion transfer of creatinine (CRE) at a polarized nitrobenzene (NB)/water (W) interface has been studied. When the pH of the W phase is in the range of 1.2 to 4.0, a well‐defined voltammetric wave is observed for a simple transfer of CRE+ (protonated form) at the NB/W interface. This transfer reaction has been applied to develop an amperometric method for the determination of CRE in urine. In this system, the NB/W interface is covered with a dialysis membrane to prevent possible interference from urine proteins. The concentration of CRE in a urine control has successfully been determined. 相似文献
935.
936.
A series of 5-aminolevulinic acid and its alkylester methanesulfonates was exploited to photodynamic therapy(PDT) of human lymphocytic cells, U-937 in vitro. The PDT efficiency is influenced by the concentration and incubation time. Generally, for ALA and its alkylester methanesulfonates, the cell survival rate decreases and the accumulation ability of PpIX increases with the concentration and incubation time. We found that the longer carbon chain methanesulfonates(C5-S, C6-S, C8-S) exhibit better PDT effec... 相似文献
937.
The dynamic behaviors of ionic liquid samples consisting of a series of 1‐alkyl‐3‐methylimidazolium cations and various counteranionic species are investigated systematically over a wide frequency range from 1 MHz to 20 GHz at room temperature using dielectric relaxation (DR) and nuclear magnetic resonance (NMR) spectroscopies. DR spectra for the ionic liquids are reasonably deconvoluted into two or three relaxation modes. The slowest relaxation times are strongly dependent upon sample viscosity and cation size, whereas the relaxation times of other modes are almost independent of these factors. We attribute the two slower relaxation modes to the rotational relaxation modes of the dipolar cations because the correlation times of the cations evaluated using longitudinal relaxation time (T1 13C NMR) measurements corresponded to the dielectric relaxation times. On the other hand, the fastest relaxation mode is presumably related to the inter‐ion motions of ion‐pairs formed between cationic and anionic species. In the case of the ionic liquid bis(trifluoromethanesulfonyl)imide, the system shows marked dielectric relaxation behavior due to rotational motion of dipolar anionic species in addition to the relaxation modes attributed to the dipolar cations. 相似文献
938.
Yoshinori Mizuno 《Mathematische Zeitschrift》2012,272(3-4):1115-1135
We give meromorphic continuations and functional equations of Mellin transform and Rankin–Selberg convolution associated with a real analytic Eisenstein series of half-integral weight. Applications to Dirichlet series whose coefficients are the class numbers of binary quadratic forms are given. 相似文献
939.
For an analytic function f (z) on the unit disk |z| < 1 with f (0) = f′(0) ? 1 = 0 and f (z) ≠ 0, 0 < |z| < 1, we consider the power deformation f c (z) = z(f (z)/z) c for a complex number c. We determine those values c for which the operator \({f \mapsto f_c}\) maps a specified class of univalent functions into the class of univalent functions. A little surprisingly, we will see that the set is described by the variability region of the quantity zf′(z)/ f (z), |z| < 1, for most of the classes that we consider in the present paper. As an unexpected by-product, we show boundedness of strongly spirallike functions. 相似文献
940.
Toshiyuki Doi 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2012,63(6):1091-1102
Plane Poiseuille flow of a highly rarefied gas that flows horizontally in the presence of weak gravitation is studied based on the Boltzmann equation for a hard sphere molecular gas and the diffuse reflection boundary condition. The behavior of the solution in the regime of large mean free path and small strength of gravity is studied numerically based on the one-dimensional Boltzmann equation derived by means of the asymptotic analysis for a slow variation in the flow direction. It is clarified that the effect of weak gravity on the flow is not negligible when the gas is so rarefied that the mean free path is comparable to the maximum range that the molecules travel along the parabolic path within the channel. When the mean free path is much larger than this range, the effect of gravity that makes the molecules fall plays the dominant role in determining the distribution function, and thus the over-concentration in the distribution function as well as the flow velocity does not increase further even if the mean free path is increased. The upper bound of the flow velocity and the mass flow rate of the gas are obtained as a function of the gravitational acceleration. 相似文献