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81.
Yotaro Morishima Shigeki Nomura Mikiharu Kamachi 《Journal of polymer science. Part A, Polymer chemistry》1994,32(16):3141-3146
3,7-Diethyl- 10-phenylphenothiazine (DEPPT), a phenothiazine derivative whose 3,7- and 10-positions are blocked, was synthesized. Potentiostatic electrolysis of DEPPT in acetonitrile (ACN) in the presence of 0.1M of LiClO4 at 0.7 V (vs. Ag/Ag/Cl) yielded the stable cation radical of DEPPT (DEPPT+·) which was characterized by cyclic voltammetry, UV-visible spectroscopy, and ESR spectrometry. Stable cation radicals of 10-phenylphenothiazine and 3,7-diethyl-10-methylphenothiazine were also prepared. The cationic polymerization of n-butyl vinyl ether was initiated by these cation radicals, including DEPPT·+. The electron transfer mechanism for the initiation step, which we proposed previously, was supported by the fact that DEPPT·+ was capable of initiating the polymerization; dimerization of DEPPT·+ by releasing protons is precluded because 3,7- and 10-positions are all blocked. © 1994 John Wiley & Sons, Inc. 相似文献
82.
83.
Electroreduction of methacryloylacetone and its FeIII and CuII complexes was studied by cyclic voltammetry and preparative electrolysis on a Hg electrode. The possibility of the electropolymerization of the compounds at highly negative potentials (–2.0 V, vs sce) has been demonstrated. The polymers obtained were characterized by elemental analysis, electronic, IR-, and Mössbauer spectroscopy.For part 36, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 255–261, February, 1994. 相似文献
84.
G. Yu. Lopatkova E. I. Volodina N. D. Pis’menskaya Yu. A. Fedotov D. Cot V. V. Nikonenko 《Russian Journal of Electrochemistry》2006,42(8):847-854
Transport characteristics of commercial heterogeneous anion-exchange membranes MA-40 and MA-41 are studied, together with those of membrane MA-40M fabricated by treating the MA-40 surfaces with a strong polyelectrolyte complex. It is demonstrated that, after modification, the electrical conductivity of MA-40M in an NaOH solution increases. At overlimiting currents, the water dissociation rate on this membrane decreases as compared with the initial membrane. At the same time, no noticeable change in the rate of transport of counter-ions (ions Cl-) through the membrane at a fixed potential drop is discovered at under-and overlimiting currents. The MA-40M membrane behavior is explained by the conversion of secondary and tertiary functional ammonium groups in the near-surface membrane layers approximately 80 μm thick into quaternary groups during the treatment by the polyelectrolyte. 相似文献
85.
A kinetic analysis of multistep electrochemical reactions involving partial diffusion transport of intermediates between the near-electrode layer and the bulk electrolyte is performed within theory of generalized variables (theory of similarity). Dimensionless complexes (similarity criteria) that characterize such reactions are obtained, and their values corresponding to the transport of intermediates are determined.Translated from Elektrokhimiya, Vol. 41, No. 1, 2005, pp. 121–125.Original Russian Text Copyright © 2005 by Protsenko, Danilov. 相似文献
86.
0IntroductionAs the active sites of several mononuclear en-zymes are five-or six-coordinate manganese speciescontaining coordinated carboxylate groups,water andnitrogen-donor molecules research on the coordinationcompounds of manganese with such coligands hasgrown[1,2].There has been extensive interest in man-ganese chemistry due to the involvement of manganesein many biosystems and magnetic materials[3 ̄5].Theisophthalate as a potential bidentate ligand seemsquite suitable for self-assembly s… 相似文献
87.
A. I. Dikusar O. O. Redkozubova S. P. Yushchenko L. B. Kriksunov D. Harris 《Russian Journal of Electrochemistry》2003,39(10):1073-1077
Experimental study of the distribution of local rates of electrochemical micromachining in the presence of photoresist masks in various hydrodynamic conditions (macroscopically nonuniform rotating disk electrode, sprayer flow, an electrode placed into a cell with chaotic bulk electrolyte mixing) shows that the maximum etching localization is achieved at the control of the dissolution rate by the mass transport rate (at achieving the anodic limiting current). The localization enhancement as compared to the primary current distribution takes place in the case of a turbulent flow at hydrodynamic conditions where the removal of dissolution products from the undercutting region is hindered. These conditions (electrochemical reaction limited by the ion mass transport rate, high resistance to the mass transport in the undercutting region) are necessary for the localization enhancement using a pulsed anodic–cathodic treatment. 相似文献
88.
碳包覆LiFePO4的一步固相法制备及高温电化学性能 总被引:8,自引:0,他引:8
Carbon coated LiFePO4 cathode material was synthesized by one-step solid-state reaction and characterized by X-ray diffraction (XRD), field-emission-scanning electron microscope (FESEM). Electrochemical performances of the material as cathode in lithium-ion battery were investigated at medium and elevated temperature (30 and 55 ℃) by galvanostatic charge-discharge and A.C. impedance tests. The results show that carbon coated LiFePO4 powder exhibits a well-crystallized olivine structure and spherical morphology with an average particle size of about 500 nm. Galvanostatic charge-discharge tests show that the reversible discharge capacity at 1 C and 1.5 C rates was improved from 121 and 105 mAh·g-1 at 30 ℃ to 136 and 123 mAh·g-1 at 55℃, respectively, while the enhancement of high temperature on electrochemical performance is less obvious at a rate lower than 0.5 C. Impedance spectra analyses indicate that the cathode material has a remarkably higher lithium-ion diffusivity at 55 ℃ than that at 30 ℃, which improves the electrochemical performance at high temperature. 相似文献
89.
S. Yu. Ryabova E. Yu. Khmel’nitskaya N. A. Rastorgueva N. B. Grigor’ev V. G. Granik 《Russian Chemical Bulletin》2004,53(12):2830-2833
Electrochemical reduction of 1-aryl-2-oxo-1,2,3,6-tetrahydro[1,4]diazepino[6,5-b]indole 4-oxides, 2-oxo-1-phenyl-1,2,3,6-tetrahydro[1,4]diazepino[6,5-b]indole, and 2-oxo-1-phenyl-1,2,3,4,5,6-hexahydro[1,4]diazepino[6,5-b]indole was studied. The results obtained were compared with previous data for the reduction of 4-oxides with formamidinesulfinic acid.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2715–2718, December, 2004. 相似文献
90.
在电极袭面反应物浓度均匀的近似假设下,得到了微圆盘电极上暂态可逆反应的一般解.然后利用该一般解得到了微圆盘电极上耦合一级均相反应的可逆电极反应CE、EC、EC′和ECE 的稳态电流计算公式. 相似文献