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951.
We consider a class of convex integral functionals with lagrangeans depending only on the gradient and satisfying a generalized
symmetry assumption, which includes as a particular case the rotational symmetry. Adapting the method by A. Cellina we obtain
a kind of local estimates for minimizers in the respective variational problems, which is applied then to deduce some versions
of the Strong Maximum Principle in the variational setting. 相似文献
952.
Inside Cover: Selective Protein Hyperpolarization in Cell Lysates Using Targeted Dynamic Nuclear Polarization (Angew. Chem. Int. Ed. 36/2016)
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953.
Tails of distributions having the form of the geometric convolution are considered. In the case of light-tailed summands,
a simple proof of the famous Cramér asymptotic formula is given via the change of probability measure. Some related results
are obtained, namely, bounds of the tails of geometric convolutions, expressions for the distribution of the 1st failure time
and failure rate in regenerative systems, and others. In the case of heavy-tailed summands, two-sided bounds of the tail of
the geometric convolution are given in the cases where the summands have either Pareto or Weibull distributions. The results
obtained have the property that the corresponding lower and upper bounds are tailed-equivalent.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
954.
955.
JPC – Journal of Planar Chromatography – Modern TLC - The chromatographic behavior of fullerene C60 has been studied on silica gel layers impregnated with solutions of glucose, sucrose,... 相似文献
956.
Renzo C. Silva Giovanna F. Carneiro Lúcio L. Barbosa Valdemar Lacerda Jr. Jair C. C. Freitas Eustáquio V. R. de Castro 《Magnetic resonance in chemistry : MRC》2012,50(2):85-88
Low‐field 1H NMR was used in this work for the analysis of mixtures involving crude oils and water. CPMG experiments were performed to determine the transverse relaxation time (T2) distribution curves, which were computed by the inverse Laplace transform of the echo decay data. The instrument's ability of quantifying water and petroleum in biphasic mixtures following different methodologies was tested. For mixtures between deionized water and petroleum, one achieved excellent results, with root mean squared error of cross‐validation (RMSECV) of 0.8% for a regression between the water content (wt %) and the relative area of the water peak in the T2 distribution curve, or a standard deviation of 0.9% for the relationship between the water content and the relative water peak area, corrected by the relative hydrogen index of the crude. In the case of biphasic mixtures of Mn2+‐doped water and crude oils, the best result of RMSECV = 1.6% was achieved by using the raw magnetization decay data for a partial least squares regression. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
957.
Manuel J. Castro Sergio Ortega Marc de la Asunción José M. Mantas José M. Gallardo 《Comptes Rendus Mecanique》2011,339(2-3):165-184
This article is a review of the work that we are carrying out to efficiently simulate shallow water flows. In this paper, we focus on the efficient implementation of path-conservative Roe type high-order finite volume schemes to simulate shallow flows that are supposed to be governed by the one-layer or two-layer shallow water systems, formulated under the form of a conservation law with source terms. The implementation of the scheme is carried out on Graphics Processing Units (GPUs), thus achieving a substantial improvement of the speedup with respect to normal CPUs. Finally, some numerical experiments are presented. 相似文献
958.
959.
Márcia R. S. Silva Mary C. F. Alves S. J. G. Lima L. E. B. Soledade Elaine C. Paris E. Longo A. G. Souza Iêda M. G. Santos 《Journal of Thermal Analysis and Calorimetry》2009,97(2):559-564
Sr(Ti,Nd)O3 was synthesized in order to evaluate the influence of the amount of neodymium on the thermal and structural properties of
SrTiO3. The synthesis was carried out using the polymeric precursor method. A small mass gain was observed for the SrTiO3 and SrTi0.98Nd0.02O3 samples accompanied by an exothermic peak in the DTA curves. Other steps at higher temperatures are assigned to the combustion
of the organic material and carbonate. Elimination of defects by previous calcination of the precursors is responsible by
the short and long range ordering of the perovskite. Cubic phase was obtained for undoped and doped SrTiO3. 相似文献
960.
Qingying Bu Gerard Buskes Alexey I. Popov Adi Tcaciuc Vladimir G. Troitsky 《Positivity》2013,17(2):283-298
We investigate the relationship between the diagonal of the Fremlin projective tensor product of a Banach lattice E with itself and the 2-concavification of E. 相似文献