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1.
Within the framework of microscopic fluctuation-dissipation theory, we obtain the stochastic equation describing the Brownian motion of an electron in the phonon field of the crystal lattice. An expression for the Green’s function of the phonon field is found in general form and for the case of linear phonon-variable interaction of an electron with the phonon field with allowance for the potential screening of crystal-lattice nuclei. An expression for the phonon drag acting on a conduction electron in the lattice field is found and analyzed with allowance for the interaction. Frequency dependence of the coefficient of the phonon drag acting on a conduction electron is studied and the contribution of the electron-phonon interaction to the effective mass of a charge carrier is determined.__________Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 48, No. 3, pp. 249–268, March 2005. 相似文献
2.
Richard P. Kent IV 《Geometriae Dedicata》2004,106(1):145-159
We answer a question of J. Anderson's by producing infinitely many commensurability classes of fibered hyperbolic 3-manifolds whose fundamental groups contain subgroups that are locally free and not free. These manifolds are obtained by performing 0–surgery on a collection of knots with the same properties. 相似文献
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5.
A. Yu. Korontzevich V. N. Vorobiev A. T. Serodzhev R. Kh. Karimov K. Kh. Razikov 《Reaction Kinetics and Catalysis Letters》1986,30(2):283-288
Diffuse reflectance spectroscopy and X-ray phase analysis studies of Ag/–Al2O3 catalysts have revealed that in thermal decomposition of supported silver nitrate part of Ag+ ions are oxidized to Ag2+ and Ag3+ ions localized in the carrier lattice, which preserve up to temperatures above 900 °C.
Ag/–Al2O3 . , Ag+ Ag2+ Ag3+, 900 °C.相似文献
6.
E. Ardashev V. Avdeichikov V. Balandin G. Bogdanova V. Dunin O. Gavrishchuk V. Golovkin S. Golovnya S. Gorokhov A. Isupov A. Kazakov A. Kholodenko A. Kiryakov E. Kokoulina A. Kutov N. Kuzmin I. Lobanov V. Nikitin Yu. Petukhov G. Pokatashkin M. Polkovnikov V. Popov S. Reznikov V. Rogov V. Ronzhin I. A. Rufanov V. Ryadovikov Yu. Tsyupa V. Volkov A. Vorobiev N. Zhidkov L. Zolin 《The European Physical Journal A - Hadrons and Nuclei》2016,52(8):261
7.
Enrique Castillo Rosa Eva Pruneda MÓnica Esquivel IV 《International Journal of Mathematical Education in Science & Technology》2013,44(2):209-232
The paper presents a method for generating random linear programming problems with a previously selected type of solution. The user can choose a problem whose solution is unbounded, bounded for minima, maxima or both, unique or multiple, with given structure, at wish. Initially, the feasible solution of the LPP is generated as the sum of a linear space, a cone, and a polytope, depending on the desired properties of the solution. With the aim of obtaining a simple set of constraints, the generators of these three structures are selected as random vectors with integer simple components, the range of which can be given. Next, an objective function that satisfies the required conditions, i.e. leads to a solution of the desired type, is obtained. The generating algorithms have been implemented in Mathematica and some illustrative examples are given to clarify the generation process. With this tool, a LPP can be generated, according to the instructor requirements, where this is a human or an expert system. They can control student progress and generate a sequence of problems covering all possible cases, in steps of increasing difficulty. Combining this tool with another (also produced by the same authors) that solves the problems and explains the whole process, step by step, a computer aided module for learning LPP, which is completely autonomous, can be easily obtained. 相似文献
8.
I. V. Shestak E. V. Vorobieva I. I. Basalyga P. D. Vorobiev D. V. Cherednichenko 《Russian Journal of Inorganic Chemistry》2012,57(1):33-38
The results of studies of the mechanism of action of sodium polyacrylate on the nucleation and crystal growth for carbonate
salts under precipitation-simulating conditions are considered. 相似文献
9.
WILLIAM T. SLAVEN IV CHAO-JUN LI YI-PING CHEN VIJAY T. JOHN SUGUNA H. RACHAKONDA 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(7-8):971-980
ABSTRACT A high molecular weight poly(aryleneethynylene) (Mw ~ 60,000) is prepared by the palladium catalyzed copolymerization of 3,5-diiodobenzoic acid and acetylene gas in a basic aqueous medium. The polymer has a “zig-zag”, fully conjugated backbone. The polymer has been characterized by a variety of methods and exhibits high thermal stability. Furthermore, the polymer is readily soluble in aqueous base and is reversibly switchable from the solution state to a hydrogel state, in water, by changing the pH of the solvent. 相似文献
10.
Isoflavonoids are a class of organic compounds that act primarily as antioxidants. They are produced almost exclusively by various members of the bean family including soybeans, tofu, peanuts, chick peas, and alfalfa. The antioxidant characteristics that isoflavonoids exhibit help hinder the progression of certain cancers, primarily breast, prostate, and colon cancer. We have developed a three-five step synthesis for obtaining a suite of isoflavonoid derivatives. The synthesis involves an enamine formation, a ring closure and halogenation, a Suzuki coupling, and finally a global deprotection to obtain the respective isoflavonoid derivatives. 相似文献