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971.
V. V. Elkin 《Russian Journal of Electrochemistry》2009,45(1):58-64
The electrochemical impedance of charge-transfer reaction involving the stages of adsorption and desorption of intermediate partially charged substance is analyzed theoretically in the frequency-potential plane in order to study the possibility for measuring the partial charge transfer. The simplest case of adsorption two-electron transfer, namely, the Langmuir adsorption with liner dependence of reaction rate on the coverage, is considered. It is assumed that the partial charge transfer is independent of the electrode potential. 相似文献
972.
The reactions of 2,4,6-trinitrotoluene with alkanethiols in the presence of K2CO3 (the molar ratio of the reactants is 1 : 1 : 1) in dipolar aprotic solvents result in selective replacement of the ortho-nitro group to form 2-alkylthio-4,6-dinitrotoluenes, which can be oxidized to the corresponding sulfoxides or sulfones. The second ortho-nitro group can be replaced under the action of one more equivalent of alkanethiol on sulfides as exemplified in PhCH2SH. 相似文献
973.
Vostrikov N. S. Abutkov A. V. Spirikhin L. V. Fatykhov A. A. Miftahov M. S. 《Russian Chemical Bulletin》2001,50(4):654-658
The Reformatsky reaction of bornanic enone (10-nor-1-vinylcamphor) with ethyl iodoacetate followed by iodocyclization afforded tricyclic iodolactone. Fragmentation of the latter initiated by HgO—I2 gave rise to bicyclic iodoxolactone. Attempts to perform cyclization of this iodoxolactone analogously to intramolecular alkylation of CH-acids with halogen-containing electrophiles failed. 相似文献
974.
抛射体运动方程的非近似解的一种求法 总被引:1,自引:1,他引:0
给出一种在考虑地球自转情况下求解抛射体运动方程的非近似解的较简便方法。 相似文献
975.
We consider survival probabilities for the discrete-time process in one dimension, which is known as the Domany–Kinzel model. A convergence theorem for infinite systems can be obtained in the nonattractive case. 相似文献
976.
《Journal of Nonlinear Mathematical Physics》2013,20(4):483-490
It is shown that the AKNS hierarchy with self-consistent sources can transform to KN hierarchy with self-consistent sources through a transformation operator and gauge transformation. Besides, there exists transformation in their conservation laws and Hamiltonian structures. 相似文献
977.
本文利用(υ_s,υ_t)平面双流网络的平面性,找出并证明了该网络中最小费用双流的充要条件,最后给出了一个算法并估计了复杂性. 相似文献
978.
In this paper, we investigate the existence of multiple solutions for a class of biharmonic equations where the nonlinearity involves a concave term at the origin. The solutions are obtained from the versions of mountain pass lemma and linking theorem. 相似文献
979.
《Acta Mechanica Solida Sinica》2011,(Z1):95-106
Stress calculation formulae for a ring have been obtained by using Airy stress function of the plane strain field with the decomposition of the solutions for normal stresses of Airy biharmonic equation into two parts when it is loaded under two opposite inside forces along a diameter. One part should fulfill a constraint condition about normal stress distribution along the circumference at an energy valley to do the minimum work. Other part is a stress residue constant. In order to verify these formulae and the computed results, the computed contour lines of equi-maximal shear stresses were plotted and quite compared with that of photo-elasticity test results. This constraint condition about normal stress distribution along circumference is confirmed by using Greens’ theorem. An additional compression exists along the circumference of the loaded ring, explaining the divorcement and displacement of singularity points at inner and outer boundaries. 相似文献
980.
讨论了两列光波发生干涉现象的理想化条件和在实验中能否观察到干涉现象发生的操作性条件,推导了各种情况下的理论公式。从工程应用的角度出发,研究了检测仪器的响应时间T和光强分辨能力对观察光的干涉现象的影响,提出了观察光的干涉现象的第四个必要条件,对在各种情况下应用光的干涉现象有一定的指导作用。 相似文献