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941.
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943.
Abstract A number of recently graph matrices encoding in various ways the topological information is presented. Four graph operators are used to compute 19 topological indices for a set of 306 alkanes. The intercorrelation coefficients of the 19 topological indices are computed and used to identify highly intercorrelated indices. 相似文献
944.
In this paper, we study the existence of solutions for noncoercive mixed equilibrium problems which are described by the sum of a maximal monotone bifunction and a pseudomonotone (or quasimonotone) bifunction in the sense of Brézis. Our approach is based on recession analysis and on recent results established by the authors for the existence of solutions of mixed equilibrium problems under pseudomonotone perturbations. As an application, we study the existence of solutions for nonlinear evolution equations associated with a noncoercive time-dependent pseudomonotone (or quasimonotone) operator. 相似文献
945.
946.
文章给出了对称拓扑分子格的直和概念,给出了拓扑分子格的直和的特征,证明了对称拓扑分子格的分离性Ti(i=-1,0,1,2)及可数性CⅠ,CⅡ是可和性质. 相似文献
947.
For any arrangement of hyperplanes in ℂℙ3, we introduce the soul of this arrangement. The soul, which is a pseudo-complex, is determined by the combinatorics of the
arrangement of hyperplanes. In this paper, we give a sufficient combinatoric condition for two arrangements of hyperplanes
to be diffeomorphic to each other. In particular we have found sufficient conditions on combinatorics for the arrangement
of hyperplanes whose moduli space is connected. This generalizes our previous result on hyperplane point arrangements in ℂℙ3.
This work was partially supported by NSA grant and NSF grant 相似文献
948.
D.H. Delphenich 《Annalen der Physik》2010,522(12):874-903
The problem of extending fields that are defined on lattices to fields defined on the continua that they become in the continuum limit is basically one of continuous extension from the 0‐skeleton of a simplicial complex to its higher‐dimensional skeletons. If the lattice in question has defects, as well as the order parameter space of the field, then this process might be obstructed by characteristic cohomology classes on the lattice with values in the homotopy groups of the order parameter space. The examples from solid‐state physics that are discussed are quantum spin fields on planar lattices with point defects or orientable space lattices, vorticial flows or director fields on lattices with dislocations or disclinations, and monopole fields on lattices with point defects. 相似文献
949.
950.
A Quantitative structure–activity relationship study is performed on a set of organophosphorus compounds to reveal structural and quantum‐chemical features influencing the toxic effect. The properties derived from the topological analysis of the electron density have been used to model the toxicity data. A multiple linear regression analysis in conjunction with genetic algorithm is used in the study, followed by subsequent validation of the results. Obtained QSAR models are beneficial for virtual screening of toxicity for new compounds of interest. Because toxicity of organophosphorus compounds is dependent on conformational properties, a conformational search has been performed before optimization of geometries. All quantum‐chemical calculations are carried out at DFT/B3LYP level of theory with 6‐311++G(d,p) basis set. Frequency calculations are performed after full geometry optimization. Ab initio wave functions were obtained for further analysis and evaluation of quantum topological properties of target molecules. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012 相似文献