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1.
A. D. Davydov V. M. Volgin V. V. Lyubimov 《Russian Journal of Electrochemistry》2004,40(12):1230-1265
Basic problems of metal electrochemical shaping theory are considered. Exact and approxi1mate (quasi-steady-state, locally one-dimensional) methods for solving direct and inverse problems are analyzed. Experimental methods for improving the electrochemical shaping accuracy are considered.Translated from Elektrokhimiya, Vol. 40, No. 12, 2004, pp. 1438–1480.Original Russian Text Copyright © 2004 by Davydov, Volgin, Lyubimov. 相似文献
2.
Molecular dynamics simulation of poly(3‐hexylthiophene) helical structure In Vacuo and in amorphous polymer surrounding
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Natalia I. Borzdun Sergey V. Larin Stanislav G. Falkovich Victor M. Nazarychev Igor V. Volgin Alexander V. Yakimansky Alexey V. Lyulin Vikas Negi Peter A. Bobbert Sergey V. Lyulin 《Journal of Polymer Science.Polymer Physics》2016,54(23):2448-2456
The stability of poly(3‐hexylthiophene) (P3HT) helical structure has been investigated in vacuo and in amorphous polymer surrounding via molecular dynamics‐based simulations at temperatures below and above the P3HT melting point. The results show that the helical chain remains stable at room temperature both in vacuo and in amorphous surrounding, and promptly loses its structure at elevated temperatures. However, the amorphous surrounding inhibits the destruction of the helix at higher temperatures. In addition, it is shown that the electrostatic interactions do not significantly affect the stability of the helical structure. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 2448–2456 相似文献
3.
The problem of determining the limiting current density of copper electrodeposition on the vertical electrode under the conditions of electrolyte natural convection is solved numerically. The incomplete dissociation of copper sulfate and sulfuric acid by the second stage and the concentration dependences of physicochemical properties of solution are taken into consideration. The effect of incomplete dissociation of copper sulfate and sulfuric acid by the second stage on the ionic transport in the copper electrodeposition and on the limiting current density is estimated by comparing the results, which are calculated taking into account and ignoring the concentration dependences of dissociation constants, and also for the limiting cases of virtually complete dissociation of copper sulfate and sulfuric acid. It is shown that, in excess of supporting electrolyte, incomplete dissociation of copper sulfate and sulfuric acid only slightly affects the limiting current density: the limiting current density changes not more than by 10% with the variation of the dissociation constants by several orders of magnitude. At the moderate and small concentrations of supporting electrolyte, incomplete dissociation should be taken into account, because the error of limiting current density can exceed 50%. 相似文献
4.
主要介绍自由电子激光相干强太赫兹源(FEL-THz)装置上的砷化镓光阴极直流高压注入器的研究进展,并讨论其驱动未来高重复频率短波长自由电子激光器的差距。通过综合砷化镓阴极寿命的三大影响因素,提出了其工作寿命的定性物理模型;通过该模型对阴极和注入器进行优化,在直流高压电子枪上得到了5 mA, 32 min的连续稳定输出;测量了电子束在4.8 mA下归一化发射度约为4.0 mmmrad,阴极热发射度约为0.6 mmmrad,电子束本征横向能量约为92 meV,250 keV电子束在距离阴极90.6 cm处纵向均方根长度约为11.5 ps。这一束流状态已经基本满足FEL-THz需求。 相似文献
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Churikov A. V. Volgin M. A. Pridatko K. I. Ivanishchev A. V. Gridina N. A. L'vov A. L. 《Russian Journal of Electrochemistry》2003,39(5):531-541
Basic kinetic parameters of electrochemical intercalation of lithium into thin carbon films are determined by relaxation methods of current and potential steps. The overall electrode polarization is theoretically and experimentally divided into kinetic and diffusion constituents. The former is connected with the hindered ion transfer in a surface solid-electrolyte layer. The latter is due to the slow diffusion of lithium inside the carbon matrix. Concentration dependences of parameters of a solid-electrolyte layer and those of the diffusion coefficient for lithium in carbon are determined at lithium concentrations in the electrode varied from 2 to 16 M. The kinetic current is dependent on polarization in the interval 0.01 to 2.5 V, the dependence being identical to that for a lithium electrode. 相似文献
7.
The microdispersed sintered nanodiamonds are evaluated as a new prospective stationary phase for normal-phase high-performance liquid chromatography. 相似文献
8.
The mass transfer in the electrolyte solution with three types of ions in the electrochemical cell of square section with
vertical electrodes is studied. The mathematical model of the process involves the Navier-Stokes equations in the Boussinesq
approximation, the equations of ionic transfer of electrolyte components, which is caused by diffusion, convection, and migration,
and the condition of electroneutrality. It is shown that this problem corresponds to a special case of thermosolutal convection
with regard for thermodiffusion (the Soret effect), where the cell boundaries are permeable to an impurity and the flux of
impurity through the boundary is proportional to the heat flux. Using the numerical simulation, the distributions of concentration
of ions, solution density, local and average mass-transfer rates are studied. The approximate analytical equations for the
limiting current are obtained for typical electrochemical systems. 相似文献
9.
NL Asfandiarov AI Fokin VG Lukin EP Nafikova GS Lomakin VS Fal'ko YV Chizhov 《Rapid communications in mass spectrometry : RCM》1999,13(12):1116-1123
A series of anthraquinone (C(14)O(2)H(8)) derivatives has been studied by means of electron capture negative ion mass spectrometry (ECNI-MS), photoelectron spectroscopy (PES), and AM1 quantum chemical calculations. Mean lifetimes of molecular negative ions M(-.) (MNI) have been measured. The mechanism of long-lived MNI formation in the epithermal energy region of incident electrons has been investigated. A simple model of a molecule (a spherical potential well with the repulsive centrifugal term) has been applied for the analysis of the energy dependence of cross sections at the first stage of the electron capture process. It has been shown that a temporary resonance of MNI at the energy approximately 0.5 eV corresponds to a shape resonance with lifetime 1-2.10(-13) s in the f-partial wave (l = 3) of the incident electron. The next resonant state of MNI at the energy approximately 1.7 eV has been associated with the electron excited Feshbach resonance (whose parent state is a triplet npi* transition). In all cases the initial electron state of the MNI relaxes into the ground state by means of a radiationless transition, and the final state of the MNI is a nuclear excited resonance with a lifetime measurable on the mass spectrometry timescale. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
10.
Theoretical analysis of a model electrochemical system is performed. An equation for the critical time of the onset of a convective instability and natural convection in a plane electrolyte layer between two horizontal electrodes is derived. The cessation of damping of fluctuations of the electroactive-ion concentration is taken as the condition for the onset of a convective instability. 相似文献