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991.
992.
H. Beirão da Veiga 《Journal of Mathematical Analysis and Applications》2008,344(1):175-185
In the following we study a class of stationary Navier-Stokes equations with shear dependent viscosity, under the non-slip (Dirichlet) boundary condition. We consider pseudo-plastic fluids. A fluid is said pseudo-plastic, or shear thinning, if in Eq. (1.1) below one has p<2. We are interested in global (i.e., up to the boundary) regularity results, in dimension n=3, for the second order derivatives of the velocity and the first order derivatives of the pressure. We consider a cubic domain Ω and impose the non-slip boundary condition only on two opposite faces. On the other faces we assume periodicity, as a device to avoid effective boundary conditions. This choice is made so that we work in a bounded domain Ω and simultaneously with a flat boundary. 相似文献
993.
Rafael Y. O. Moreira Davi S. B. Brasil Cláudio N. Alves Giselle M. S. P. Guilhon Lourivaldo S. Santos Mara S. P. Arruda Adolfo H. Müller Patrícia S. Barbosa Alcicley S. Abreu Edilene O. Silva Victor M. Rumjanek Jaime Souza Jr. Albérico B. F. da Silva Regina H. de A. Santos 《International journal of quantum chemistry》2008,108(3):513-520
Julocrotine, N‐(2,6‐dioxo‐1‐phenethyl‐piperidin‐3‐yl)‐2‐methyl‐butyramide, is a potent antiproliferative agent against the promastigote and amastigote forms of Leishmania amazonensis (L.). In this work, the crystal structure of Julocrotine was solved by X‐ray diffraction, and its geometrical parameters were compared with theoretical calculations at the B3LYP and HF level of theory. IR and NMR spectra also have been obtained and compared with theoretical calculations. IR absorptions calculated with the B3LYP level of theory employed together with the 6‐311G+(d,p) basis set, are close to those observed experimentally. Theoretical NMR calculations show little deviation from experimental results. The results show that the theory is in accordance with the experimental data. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 相似文献
994.
Heck reactions between iodobenzene and methyl acrylate were carried out in monoglyme and diglyme as solvents, using different ligands and palladium sources, and good to high yields were obtained in the production of (E)‐substituted olefins. The ionic liquid BmimCl was successfully utilized as pre‐ligand to substitute triphenylphosphine. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
995.
996.
Lurdes M. Ciríaco Isabel M. da Silva Pereira Manuel R. Nunes Helena M. Mendonça Fernanda M. Costa 《Journal of Solid State Electrochemistry》2001,5(7-8):495-501
The effect of the partial substitution of tantalum by iron on the structural and electrical properties of the KTaO3 perovskite-type oxide powders has been studied. The powders were prepared by the standard ceramic method, and the respective
structural characterization performed by X-ray powder diffraction. From the synthesized oxide samples, iron-coated electrodes
were fabricated and tested as the anode for the oxygen evolution reaction in alkaline medium. An estimation of the electrode's
capacity has been calculated from the charging currents and the corresponding roughness factor evaluated. The electrocatalytic
activity/stability of the oxide electrodes in alkaline solutions has been analysed through the kinetic parameters.
Electronic Publication 相似文献
997.
José C. Araujo da Silva Marc Birot Marie-Thérèse Rayez 《Journal of organometallic chemistry》2008,693(15):2592-2596
Silylboranes with aromatic substituents linked to boron and silicon exhibit an unexpected absorption band in the UV-Vis spectral region. When polar groups were introduced, a marked solvatochromic effect was observed in their fluorescence emission spectra, revealing a strong excited state dipole moment. Semi-empirical MNDO/d and AM1 calculations showed that, upon UV excitation, the polarity of the Si-B bond increased and the aromatic π-electrons migrated toward the Si-B bond, consistent with experimental observations. 相似文献
998.
de Souza Cabrini F. da Cunha Alessandra L. M. C. Auclio Ricardo Queiroz 《Chromatographia》2009,70(9-10):1461-1466
Micellar electrokinetic capillary chromatography was used for the determination of picoxystrobin and pyraclostrobin. The background electrolyte consisted of borate buffer (40 mmol L−1 pH 8.5), SDS (30 mmol L−1) and acetonitrile (15% in volume). Runs were made at 25 °C with 25 kV applied potential. The developed method was applied to analyte fortified urine samples. On-line analyte concentration, combined with a capillary of a longer optical path length, allowed limits of quantification of 8.6 × 10−8 mol L−1 for picoxystrobin and 1.8 × 10−7 mol L−1 for pyraclostrobin.
相似文献999.
We study the existence of multiple solutions for a quasilinear elliptic system of gradient type with the possibility of coupling on the critical and subcritical terms which are not necessarily homogeneous. The solutions are obtained from a version of the Symmetric Mountain Pass Theorem. A version of the Concentration-Compactness Principle for this class of systems allows us to verify that the Palais–Smale condition is satisfied below a certain level. 相似文献
1000.