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991.
Lie symmetry group method is applied to study the affine heat equation for surface. Its symmetry groups and corresponding optimal systems are determined, and group-invariant solutions associated to the symmetries are obtained and classified. 相似文献
992.
Vikas N. Telvekar Kavit N. Patel Harish S. Kundaikar Hemchandra K. Chaudhari 《Tetrahedron letters》2008,49(14):2213-2215
A simple and mild method for the conversion of varieties of aldehydes to the corresponding nitriles using aqueous ammonia and aqueous sodium dichloroiodate reagent at room temperature is discussed. Advantages of this system are short reaction time, easy work-up and moderate to good yields. 相似文献
993.
Vy khoi Le 《Czechoslovak Mathematical Journal》2008,58(2):541-560
The paper is about a sub-supersolution method for the prescribed mean curvature problem. We formulate the problem as a variational
inequality and propose appropriate concepts of sub-and supersolutions for such inequality. Existence and enclosure results
for solutions and extremal solutions between sub-and supersolutions are established. 相似文献
994.
主要研究一类三阶两点边值问题变号解的存在性和多重性,利用不动点指数和拓扑度理论等得到了新的结论. 相似文献
995.
In this letter, a new auxiliary function method is presented for constructing exact travelling wave solutions of nonlinear partial differential equations. The main idea of this method is to take full advantage of the solutions of the elliptic equation to construct exact travelling wave solutions of nonlinear partial differential equations. More new exact travelling wave solutions are obtained for the generalized coupled Hirota–Satsuma KdV system. 相似文献
996.
We study a new model named the Green-Lindsay type therm-elastic model for nonhomogeneous media that consists of a system of dynamic thermoelasticity equations of displacement and dynamic heat conduction equation. We construct the model based on the classical GL-model for homogeneous material. This system is coupled dynamic problem and the displacement field and heat field must be solved at the same time. By using Fadeo-Galerkin method, we proved that the problem we proposed exist unique weak solution under some regular assumption. 相似文献
997.
998.
999.
This work is concerned with the two-dimensional boundary layer flow of an upper-convected Maxwell (UCM) fluid in a channel
with chemical reaction. The walls of the channel are porous. Employing similarity transformations the governing non-linear
partial differential equations are reduced into non-linear ordinary differential equations. The resulting ordinary differential
equations are solved analytically using homotopy analysis method (HAM). Expressions for series solutions are derived. The
convergence of the obtained series solutions are shown explicitly. The effects of Reynold’s number Re, Deborah number De, Schmidt number Sc and chemical reaction parameter γ on the velocity and the concentration fields are shown through graphs and discussed. 相似文献
1000.
Alassane Diédhiou Clément Manga 《Journal of Mathematical Analysis and Applications》2008,342(1):146-160
We study the behavior of the solution of a partial differential equation with a linear parabolic operator with non-constant coefficients varying over length scale δ and nonlinear reaction term of scale 1/?. The behavior is required as ? tends to 0 with δ small compared to ?. We use the theory of backward stochastic differential equations corresponding to the parabolic equation. Since δ decreases faster than ?, we may apply the large deviations principle with homogenized coefficients. 相似文献