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951.
952.
953.
With appropriate hypotheses on the nonlinearity f, we prove the existence of a ground state solution u for the problem
(?Δ+m2)σu+Vu=(W?F(u))f(u)in RN,
where 0<σ<1, V is a bounded continuous potential and F the primitive of f. We also show results about the regularity of any solution of this problem.  相似文献   
954.
955.
956.
The free boundary problem for the three dimensional incompressible elastodynamics system is studied under the Rayleigh–Taylor sign condition. Both the columns of the elastic stress FF??I and the transpose of the deformation gradient F??I are tangential to the boundary which moves with the velocity, and the pressure vanishes outside the flow domain. The linearized equation takes the form of wave equation in terms of the flow map in the Lagrangian coordinate, and the local-in-time existence of a unique smooth solution is proved using a geometric argument in the spirit of [19].  相似文献   
957.
We study the interaction between two structures on the group of polynomial automorphisms of the affine plane: its structure as an amalgamated free product and as an infinite-dimensional algebraic variety. We introduce a new conjecture, and show how it implies the Polydegree Conjecture. As the new conjecture is an ideal membership question, this shows that the Polydegree Conjecture is algorithmically decidable. We further describe how this approach provides a unified and shorter method of recovering existing results of Edo and Furter.  相似文献   
958.
《Analytical letters》2012,45(12):633-639
Abstract

G. L. C. enabled a separation of cis- and trans-crotyl alcohol. Commercially available samples of crotyl alcohol and the products of controlled potential electrolysis of crotonaldehyde contained about 20% of the cis-form. The limited amount of information available on N. M. R. spectra of similar compounds prevented an application of the coupling constants for the interaction between a methyl group and ethylenic protons in attribution of the trans-structure. Attribution of trans-structure to the predominant form was based upon I. R. spectra and synthesis of the trans-isomer.  相似文献   
959.
We review Giroux's contact handles and contact handle attachments in dimension three and show that a bypass attachment consists of a pair of contact 1 and 2-handles. As an application we describe explicit contact handle decompositions of infinitely many pairwise non-isotopic overtwisted 3-spheres. We also give an alternative proof of the fact that every compact contact 3-manifold (closed or with convex boundary) admits a contact handle decomposition, which is a result originally due to Giroux.  相似文献   
960.
In this paper we introduce a concept of “regulated function” v(t,x) of two variables, which reduces to the classical definition when v is independent of t. We then consider a scalar conservation law of the form ut+F(v(t,x),u)x=0, where F is smooth and v is a regulated function, possibly discontinuous w.r.t. both t and x. By adding a small viscosity, one obtains a well posed parabolic equation. As the viscous term goes to zero, the uniqueness of the vanishing viscosity limit is proved, relying on comparison estimates for solutions to the corresponding Hamilton–Jacobi equation.As an application, we obtain the existence and uniqueness of solutions for a class of 2×2 triangular systems of conservation laws with hyperbolic degeneracy.  相似文献   
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