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951.
The double-layer characteristics of liquid renewable Cd–Ga (0.3 at % Cd) and In–Ga (14.2 at % In) electrodes in the gamma-butyrolactone (GBL) solutions of various electrolytes are studied by measuring the differential capacitance and using the method of open-circuit jet electrode. For the (Cd–Ga)/GBL and (In–Ga)/GBL interfaces, the zero-charge potentials, which are not distorted by the specific adsorption of ions, and the chemisorption potential drops of solvent are determined. It is shown that, in spite of the fact that the work function decreases as we pass from (In–Ga) to (Cd–Ga), the chemisorption potential drops of solvent on both electrodes are close. This behavior is explained by a closer approach of GBL dipoles to the surface of (Cd-Ga) electrode providing more effective overlapping of donor–acceptor levels of metal and solvent. It is shown that, in GBL, the adsorption parameters of halide ions and their surface activity series depend on the metal nature. On the (Cd–Ga) and (In–Ga) electrodes, the reversed surface activity series of halide ions is observed: on the Hg electrode in various solvents, the surface activity increases in the series Cl– < Br– < I–, whereas on the (Cd–Ga) and (In–Ga) electrodes in GBL, it varies in the reverse series I– < Br– < Cl–. 相似文献
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954.
Potentiostatic (galvanostatic) electrolysis of NH4SCN in an undivided cell under mild conditions (25 °C, Pt anode, MeCN) was employed to perform the anodic thiocyanation of nitrogen-containing heterocycles with yields up to 95%. The regularities of the process are discussed, which show that it can be considered as electroinduced nucleophilic aromatic substitution of hydrogen. 相似文献
955.
A mechanical system that models swimming using a pair of two-chain extremities is considered. The motion of the system under study is similar to swimming of a frog and some other animals, in which lower extremities play the main role. This type of motion is characteristic of competitive breaststroke swimming. 相似文献
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D. Grigor’ev K. B. Musabekov N. K. Musabekov Zh. Zh. Kusainova 《Polymer Science Series A》2017,59(4):506-514
IR spectroscopy and scanning electron microscopy were used for the study of formation of calcium alginate particles. The synthesis was carried out in an aqueous medium via reaction between sodium alginate and calcium chloride. It was found that calcium alginate particles with a homogeneous and dense structure were formed at concentrations 2 wt % and 0.1 M of sodium alginate and calcium chloride, respectively. Formation of calcium alginate particles in the systems containing chitosan was accompanied by the emergence of an adsorption layer of chitosan on the particle surface. The thickness of this layer increased with the enhancement of chitosan concentration. The release kinetics of cyclophosphamide from calcium alginate particles in physiological solution in vitro was investigated. The results showed that such factors as elevated temperature at the drying of calcium alginate particles, the increase in the amount of guluronate in the initial sodium alginate, and thickening of the chitosan adsorbed layer led to a significant decrease in the release rate. 相似文献
959.
A. V. Gladyshev E. Jurčišinová M. Jurčišin R. Remecký 《Physics of Particles and Nuclei》2013,44(2):272-284
Using the field theoretic renormalization group technique the model of a passive vector field advected by an incompressible turbulent flow is investigated up to the second order of the perturbation theory (two-loop approximation). The turbulent environment is given by statistical fluctuations of the velocity field that has a Gaussian distribution with zero mean and defined noise with finite correlations in time. Two-loop analysis of all possible scaling regimes in general d-dimensional space is done in the plane of exponents ? ? η, where ? characterizes the energy spectrum of the velocity field in the inertial range E ∝ k 1 ? 2ε, and η is related to the correlation time at the wave number k which is scaled as k ?2 + η. It is shown that the scaling regimes of the present model of vector advection have essentially different properties than the scaling regimes of the corresponding model of passively advected scalar quantity. The results demonstrate the fact that within the present model of passively advected vector field the internal tensor structure of the advected field can have nontrivial impact on the diffusion processes deep inside in the inertial interval of given turbulent flow. 相似文献
960.
The influence of atomic electron shells on the constant of alpha decay of heavy and mediummass nuclei was considered in detail. A method for simultaneously taking into account the change in the potential-barrier shape and the effect of reflection of a diverging Coulomb wave in the classically allowed region was developed. The ratios of decay probabilities per unit time for a bare nucleus and the respective neutral atom were found for some alpha-decaying isotopes. 相似文献