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941.
José Francisco Rodrigues Manel Sanchón José Miguel Urbano 《Monatshefte für Mathematik》2008,17(1):303-322
The aim of this paper is twofold: to prove, for L
1-data, the existence and uniqueness of an entropy solution to the obstacle problem for nonlinear elliptic equations with variable
growth, and to show some convergence and stability properties of the corresponding coincidence set. The latter follow from
extending the Lewy-Stampacchia inequalities to the general framework of L
1. 相似文献
942.
Miguel Sánchez 《Differential Geometry and its Applications》2006,24(1):21-32
Some results related to the causality of compact Lorentzian manifolds are proven: (1) any compact Lorentzian manifold which admits a timelike conformal vector field is totally vicious, and (2) a compact Lorentzian manifold covered regularly by a globally hyperbolic spacetime admits a timelike closed geodesic, if some natural topological assumptions (fulfilled, for example, if one of the conjugacy classes of deck transformations containing a closed timelike curve is finite) hold. As a consequence, any compact Lorentzian manifold conformal to a static spacetime is geodesically connected by causal geodesics, and admits a timelike closed geodesic. 相似文献
943.
A local realistic model is proposed that agrees approximately with quantum mechanics in the predictions about experiments testing Bell's inequalities by measuring polarization correlations of photon pairs emitted in atomic cascades. No free parameters exist, except polarizer efficiencies, which may be measured independently using Malu's law. 相似文献
944.
945.
Miguel Ferrero 《Foundations of Physics》2003,33(4):665-676
It has been traditionally considered that Quantum Mechanics has two conceptual kinds of problems, namely, those related with local-realism and the so-called measurement problem. That is, the uniqueness of the result when we make a measurement. With the development of what is called generically Quantum Information Theory, a new form of the Copenhagen interpretation of the formalism has taken shape.(1) In this paper, we will analyse if this information interpretation is able to clarify these old problems. Although this interpretation seems to be the most promising approach we have, we have reached the conclusion that the answer cannot be given in a positive and clear way yet. 相似文献
946.
947.
948.
949.
María A. Romero Juan M. Salas Miguel Quirós David J. Williams José Molina 《Transition Metal Chemistry》1993,18(6):595-598
Summary Several cobalt(II) complexes of 5,7-dimethyl-[1,2,4]-tria-zolo-[1,5-a]-pyrimidine (DMTP) have been prepared and characterized by thermal and spectroscopic techniques. The crystal structure of [Co(DMTP)2(H2O)4]Br2·2H2O has been determined by XRD; the metal ion is octahedrally coordinated by two DMTP ligands through the usual N(3) site and four water molecules. Metal binding to N(3) for DMTP is consistent with the electronic properties calculated with the MOPAC programme. All the complexes were screened for their activity against several types of bacteria, showing a broad-spectrum antimicrobial activity. 相似文献
950.
Costas, M. and Sanctuary, B.C., 1984. Equation of state molecular parameters for a theory of pure r-mer fluids in the liquid phase. Fluid Phase Equilibria, 18: 47–60.Equation of state parameters for a theory of pure r-mers (Costas and Sanctuary, 1981) are presented for sixty common substances. The equation of state is tested for its ability to reproduce and predict thermodynamic data in the liquid phase. The theory has only two adjustable parameters: ν*, the close-packed volume of the r-mer, and ?* = z?/2, where ? is the nonbonded mer-mer attractive interaction energy and z is the lattice coordination number, set to be a constant equal to 12. The number of r-mers per molecule, r, is also fixed for a given liquid to be equal to the number of atoms in the molecule other than hydrogen. The fitting proceduce is fast and simple. The adjustment only involves the use of widely available density data. Comparisons between experimental and calculated first- and second-order thermodynamic properties are shown for several substances. A comparison with the equation of state due to Jain and Simha (1981) for PVT data for n-dodecane is presented. The theory qualifies as a useful tool, especially in engineering applications, for estimating thermodynamic properties in the liquid phase. 相似文献