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The transient two‐layer thin‐film planar flow is investigated theoretically in this study. The interplay among inertia, viscous and surface/interfacial tension is emphasized. It is found that the film and interface profiles, as well as the flow field, are strongly influenced by the viscosity ratio, velocity and film thickness ratios at inception, and the surface‐to‐interfacial tension ratio. The nonlinear stability of the steady state reveals the formation of a solitary wave after flow inception, which propagates in the form of a convective instability, with the steady state recovered only in the tail (upstream) region of the wave. In the presence of surface/interfacial tension, surface modulation appears, which grows in wavelength and amplitude with position. The flow is found to be particularly stable for higher viscosity of the lower film layer. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
223.
Luigi C. Berselli Roger Lewandowski 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2012
We consider a 3D Approximate Deconvolution Model ADM which belongs to the class of Large Eddy Simulation (LES) models. We aim at proving that the solution of the ADM converges towards a dissipative solution of the mean Navier–Stokes equations. The study holds for periodic boundary conditions. The convolution filter we first consider is the Helmholtz filter. We next consider generalized convolution filters for which the convergence property still holds. 相似文献
224.
Pierre-Yves Roger Fabien Blondeau David Bensa Thierry Constantieux Jean Rodriguez 《Molecular diversity》2009,13(4):469-473
A new one-pot domino reaction for a general entry to functionalised bridged bicyclo[n.2.1] ring systems from α ,α’-diactivated cyclic ketones and trans-1,4-dihalides is described. The sequence combines a base promoted C–O cycloalkylation reaction leading to fused polycyclic
enol ethers and their in situ palladium-catalysed isomerisation. 相似文献
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Alexei Borodin Mihail Poplavskyi Christopher D. Sinclair Roger Tribe Oleg Zaboronski 《Communications in Mathematical Physics》2016,346(3):1051-1055
We correct an error in Theorem 12 of the original article concerning the edge scaling limit of the law of real eigenvalues for the real Ginibre ensemble. 相似文献
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Ernesto C. Tuazon Pilar Martin Sara M. Aschmann Janet Arey Roger Atkinson 《国际化学动力学杂志》2011,43(11):631-638
Rate constants for the reactions of 2‐methoxy‐6‐(trifluoromethyl)pyridine, diethylamine, and 1,1,3,3,3‐pentamethyldisiloxan‐1‐ol with OH radicals have been measured at 298 ± 2 K using a relative rate method. The measured rate constants (cm3 molecule?1 s?1) are (1.54 ± 0.21) × 10?12 for 2‐methoxy‐6‐(trifluoromethyl)pyridine, (1.19 ± 0.25) × 10?10 for diethylamine, and (1.76 ± 0.38) × 10?12 for 1,1,3,3,3‐pentamethyldisiloxan‐1‐ol, where the indicated errors are the estimated overall uncertainties including those in the rate constants for the reference compounds. No reaction of 2‐methoxy‐6‐(trifluoromethyl)pyridine with gaseous nitric acid was observed, and an upper limit to the rate constant for the reaction of 1,1,3,3,3‐pentamethyldisiloxan‐1‐ol with O3 of <7 × 10? 20 cm3 molecule?1 s?1 was determined. Using a 12‐h average daytime OH radical concentration of 2 × 106 molecule cm?3, the lifetimes of the volatile organic compounds studied here with respect to reaction with OH radicals are 7.5 days for 2‐methoxy‐6‐(trifluoromethyl)pyridine, 1.2 h for diethylamine, and 6.6 days for 1,1,3,3,3‐pentamethyldisiloxan‐1‐ol. Likely reaction mechanisms are discussed. © 2011 Wiley Periodicals, Inc. Int J Chem Kinet 43: 631–638, 2011 相似文献
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