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981.
The recently proposed multiple-scattering generalized partitioning molecular cluster model is used to calculate the electronic states of the [Pt (CN)42-] dimer units. The obtained results are related to the electronic structure of the tetracyanoplatinate precursor salt KTCP. The mechanism that places the dz2 - like band at the Fermi level in KCP quasi-one-dimensional conducting solid is analysed. 相似文献
982.
Aitala EM Amato S Anjos JC Appel JA Ashery D Banerjee S Bediaga I Blaylock G Bracker SB Burchat PR Burnstein RA Carter T Carvalho HS Copty NK Cremaldi LM Darling C Denisenko K Devmal S Fernandez A Fox GF Gagnon P Gobel C Gounder K Halling AM Herrera G Hurvits G James C Kasper PA Kwan S Langs DC Leslie J Lundberg B Magnin J MayTal-Beck S Meadows B de Mello Neto JR Mihalcea D Milburn RH de Miranda JM Napier A Nguyen A d'Oliveira AB O'Shaughnessy K Peng KC Perera LP Purohit MV Quinn B Radeztsky S 《Physical review letters》2001,86(18):3969-3972
We report results of a search for flavor-changing neutral current (FCNC), lepton flavor, and lepton-number violating decays of the D0 (and its antiparticle) into three and four bodies. Using data from Fermilab charm hadroproduction experiment E791, we examine modes with two leptons (muons or electrons) and a rho(0), K( *0), or straight phi vector meson or a nonresonant pi(pi), Kpi, or KK pair of pseudoscalar mesons. No evidence for any of these decays is found. Therefore, we present branching-fraction upper limits at 90% confidence level for the 27 decay modes examined (18 new). 相似文献
983.
Resumé On étudie les hypersurfaces exceptionnelles pour les applications holomorphes de (n). On montre qu'une telle hypersurface n'est jamais lisse dès que son degré est plus grand que deux.
Exceptional hypersurfaces for holomorphic endomorphisms of (n) are studied. We prove that such an hypersurface is not smooth as soon as its degree is greater than two.相似文献
984.
985.
We enumerate cones over singular varieties satisfying appropriate incidence conditions to linear subspaces. 相似文献
986.
J. X. Da Cruz Neto G. J. P. Da Silva O. P. Ferreira J. O. Lopes 《Computational Optimization and Applications》2013,54(3):461-472
A method for solving quasiconvex nondifferentiable unconstrained multiobjective optimization problems is proposed in this paper. This method extends to the multiobjective case of the classical subgradient method for real-valued minimization. Assuming the basically componentwise quasiconvexity of the objective components, full convergence (to Pareto optimal points) of all the sequences produced by the method is established. 相似文献
987.
988.
Fernando Martins dos Santos Jr. Gunar Vingre da Silva Mota Lucas Haidar Martorano Ana Carolina Ferreira de Albuquerque Claudinei Alves da Silva Adalberto Manoel da Silva Antônio Maia de Jesus Chaves Neto Alessandra Leda Valverde Evani Ferreira Cardoso Fabio Luiz Paranhos Costa 《Magnetic resonance in chemistry : MRC》2022,60(6):533-540
The combination of computational methods and experimental data from Nuclear Magnetic Resonance (NMR) is a considerably valuable tool in the elucidation of new natural product structures and, also, in the structural revision of previously reported compounds. Until recently, only classical statistical parameters were used, for example, linear correlation coefficient (R2), mean absolute error (MAE), or root mean square deviation (RMSD), as a way to statistically “validate” the structure pointed out by experimental NMR spectra. Regarding the resolution of the relative configuration of organic molecules, novel tools were available in the last few years to assist in the NMR elucidation process. The most relevant are DP4+, which is based on a Bayesian probability, and ANN-PRA, which is based on artificial neural networks. The combined application of these tools has become the most accurate and important alternative to solve structural and stereochemical problems in natural product chemistry. Therefore, herein, in this case study, we intended to promote these novel tools, exploring the strengths and limitations of each approach in resolving the relative configuration of the sesquiterpene alpha-bisabol. We also highlighted the advantages of the complementary use of H- and C-DP4+ to obtain optimal results in the differentiation of the stereoisomers, validating the proposal with ANN-PRA method. 相似文献
989.
990.