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11.
A time-dependent model corresponding to an Oldroyd-B viscoelastic fluid is considered, the convective terms being disregarded.
Global existence in time is proved in Banach spaces provided the data are small enough, using the implicit function theorem
and a maximum regularity property for a three fields Stokes problem. A finite element discretization in space is then proposed.
Existence of the numerical solution is proved for small data, so as a priori error estimates, using again an implicit function
theorem.
Supported by the Swiss National Science Foundation. Fellowship PBEL2–114311. 相似文献
12.
The new olefinic substituted aminodisilanes, which are obtained from the reaction of organometallic reagents with aminochlorodisilanes, are converted into the chlorodisilanes by equilibration reactions or treatment with HCI. The resulting olefinic functionalized disilanes are identified by means of 29Si, 13C, 1H NMR and GC MS measurements. 相似文献
13.
Philippe Quevauviller Rob Ritsema Roberto Morabito Wilfried M. R. Dirkx Salvatore Chiavarini Jos M. Bayona Olivier F. X. Donard 《应用有机金属化学》1994,8(6):541-549
Biogeochemical pathways of tin species in the environment are still controversial, e.g. with regard to methylation and transmethylation phenomena, owing to the fact that the identification of methylated tin-compounds is often difficult. The previous tentative identification of a mixed methylbutyltin compound in sediment and biological samples by GC/AAS after hydride generation gave an illustration of this problem. This compound was previously identified in sediments by other authors and also suspected to occur in a contaminated sediment sample from the Boyardville Marina, France. The retention time obtained by GC/AAS corresponded to the actual retention time of a mixed methylbutyltin calibrant. However, additional checks demonstrated that the compound detected was actually monophenyltin. This evidence was produced by a thorough analysis of a selected sediment sample by alternative techniques such as GC/AAS and GC/AES after pentylation, GC/FPD and GC/MS. The results presented highlight the need for a full identification of compounds to avoid mis-interpretation. 相似文献
14.
Basing on the formalism established by Markovich, we show the completeness of wave operators for the Wigner equation in L2. In the second part, using estimations proved by Castella and Perthame on the one hand, and the Lp→Lq estimations for the Schrödinger group on the other hand, we prove the existence of the wave operators in L2,p spaces. To cite this article: H. Emamirad, P. Rogeon, C. R. Acad. Sci. Paris, Ser. I 334 (2002) 811–816. 相似文献
15.
A multilayer structure consisting of undoped GaAs and AlAs layers was incorporated into a buffer layer on GaAs substrates. This reduces the spreading of impurities from the substrate (e.g. tellurium) into layers deposited on top of the multilayer system as observed by SIMS and C/V profiling. Incorporation coefficients for tellurium in GaAs, AlAs and multilayers were calculated. 相似文献
16.
Nicolas Meyer Mohamad Nasser Eddine Christelle Delaite Guy Hurtrez Philippe Dumas 《Journal of polymer science. Part A, Polymer chemistry》2003,41(21):3329-3335
The reactions of polystyryllithium and potassium on dimethoxymethyl 1,1‐diphenylethylene derivatives were studied in different solvents. In a polar medium, A3 and A6 star types were formed according to the stoichiometry, whereas in a nonpolar medium, hyperbranched structures were synthesized. Extensions of an already proposed mechanism in polar and nonpolar media were examined. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3329–3335, 2003 相似文献
17.
We consider a class of problems originating from a Raman laser amplification model, for which the equations can be written as a Poisson system with boundary conditions. Once reformulated, this system becomes an integro-differential equation that we study here in some detail. In particular, we show the existence of a smooth solution under general assumptions, and prove its uniqueness for boundary values that are not too far apart. Eventually, we completely solve the question of uniqueness for systems of dimensions one and two. To cite this article: F. Castella et al., C. R. Acad. Sci. Paris, Ser. I 336 (2003). 相似文献
18.
19.
Let be a strongly Lipschitz domain of (n?2). We give endpoint versions of div–curl lemmata on , for a given function f on whose gradient belongs to a Hardy space on . To cite this article: P. Auscher et al., C. R. Acad. Sci. Paris, Ser. I 337 (2003). 相似文献
20.
This Note gives asymptotic results for kernel estimators of several functionals (density, failure rate and distribution functions) of a long-memory process. The results are presented in such a way as to highlight the influence of the long dependence on the rates of convergence. To cite this article: G. Estevez-Perez, P. Vieu, C. R. Acad. Sci. Paris, Ser. I 335 (2002) 271–274. 相似文献