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101.
Waêl Moukarzel Jean‐Daniel Marty Dietmar Appelhans Monique Mauzac Juliette Fitremann 《Journal of polymer science. Part A, Polymer chemistry》2013,51(17):3607-3618
A straightforward method for the preparation of polysiloxanes grafted with carbohydrate side groups is described. Two kinds of backbones have been functionalized, namely one‐dimensional, linear polysiloxanes, and hyperbranched poly(siloxysilane)s based on cyclotetrasiloxanes. The method enables us to keep a good integrity of the polysiloxane backbone. The introduction of intermediate activated esters as side groups on the polysiloxane backbone ensures a complete homogeneity of the reaction medium during sugar grafting in dimethyl sulfoxide, and consequently an easy grafting with the unprotected amino sugar. Solubility of the resulting polysiloxanes has been tested in various solvents. The sugar‐grafted polysiloxanes are good candidates for applications such as silicone formulations, hydrophilic silicone elastomers, interactions with metallic nanoparticles, and suspension stabilization, or as starting point for the design of more complex polysiloxanes for molecular recognition. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3607–3618 相似文献
102.
Jean-Paul Penot 《Journal of Global Optimization》2010,47(3):503-525
We raise some questions about duality theories in global optimization. The main one concerns the possibility to extend the
use of conjugacies to general dualities for studying dual optimization problems. In fact, we examine whether dualities are
the most general concepts to get duality results. We also consider the passage from a Lagrangian approach to a perturbational
approach and the reverse passage in the framework of general dualities. Since a notion of subdifferential can be defined for
any duality, it is natural to examine whether the familiar interpretation of multipliers as generalized derivatives of the
performance function associated with a dualizing parameterization of the given problem is still valid in the general framework
of dualities. 相似文献
103.
Josiane Courtois Jean-Paul Seguin Sophie Declomesnil Alain Heyraud Philippe Colin-Morel Luciana Dantas 《Journal of carbohydrate chemistry》2013,32(4-5):441-448
Abstract A mutant of the R. meliloti M5N1 strain has been selected. This strain, R. meliloti M5N1 CS (NCIMB 40472), excretes an extracellular material composed of 2-O-Ac-β-GlcpA, 3-O-Ac-β-GlcpA, 2,3-di-O-Ac-β-GlcpA and three species of β-GlcpA residues 1→4 linked. For the culture conditions used, the weight average molecular weight of the polymer varied in the range of 6 × 104 < Mw < 4 × 105. High molecular weight glucuronate forms thermoreversible gels at 5 g L?l. In the presence of divalent cation such as Ca2+ or trivalent cations such as Cr3+ or Fe3 +, cross linking of the polymer occurs. This polysaccharide is the first exocellular (1→4)-β-D-glucuronan produced by a R. meliloti strain. 相似文献
104.
105.
106.
Jean-Paul Penot 《Computational Optimization and Applications》2002,23(3):279-284
It is proved that any cluster point of a sequence defined by a steepest descent algorithm in a general normed vector space is a critical point. The function is just assumed to be continuously differentiable. The class of algorithms we consider encompasses several choices such as the Cauchy steplength and the Curry steplength. 相似文献
107.
E. E. Shalygina A. V. Vedyaev O. A. Shalygina I. A. Pogrebnaya A. Marty B. Gilles 《JETP Letters》1998,67(1):34-38
The results of an investigation of the magnetic and magnetooptical properties of Au/Cu-wedge/15-Å-NiFe sandwiches are reported.
Oscillations of the equatorial Kerr effect as a function of the copper wedge thickness are observed. The period of these oscillations
is found to be of the order of 5–6 Å. The experimentally observed oscillations of the equatorial Kerr effect are attributed
to a quantum size effect.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 1, 33–36 (10 January 1998) 相似文献
108.
Jean-Paul Brasselet Karl-Heinz Fieseler Ludger Kaup 《Commentarii Mathematici Helvetici》1990,65(1):581-602
Sans résumé
En hommage à Jean Louis Verdier 相似文献
109.
Jean-Paul Penot 《Set-Valued Analysis》2001,9(1-2):131-157
We show that three important topics in nonlinear analysis and optimization are intimately related: the theory of perturbations, the notion of well-posedness and variational principles in the sense of Ekeland, Borwein–Preiss and Deville–Godefroy–Zizler. The concept of genericity and the new notion of flexible perturbation play a key role in these connections. This notion enables one to consider topologies on spaces of functions which have been introduced recently. A link between the Asplund and Ekeland–Lebourg methods and the Palais–Smale condition, another important topic in nonlinear analysis, is pointed out. 相似文献
110.
We have successfully developed a high-energy, high-repetition rate Ti:sapphire laser system that delivers 33 J before compression at 0.1 Hz. The final booster amplifier is based on a 100 mm diameter Ti:sapphire crystal pumped with 72 J of energy in six beams delivered by three frequency-doubled high-repetition rate Nd:glass lasers. This system is, to the best of our knowledge, the first demonstrated petawatt class laser system running at a high repetition rate. 相似文献