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31.
Winé G Matta J Tessonnier JP Pham-Huu C Ledoux MJ 《Chemical communications (Cambridge, England)》2003,(4):530-531
Beta zeolite supported on silicon carbide, with high thermal conductivity and high mechanical strength, was successfully used as an active and stable catalyst for Friedel-Crafts reactions in a fixed bed configuration. 相似文献
32.
Omar?Anza?HafsaEmail author Jean-Philippe?Mandallena 《Calculus of Variations and Partial Differential Equations》2003,18(4):433-449
We prove a new interchange theorem of infimum and integral. Its distinguishing feature is, on the one hand, to establish a general framework to deal with interchange problems for nonconvex integrands and nondecomposable sets, and, on the other hand, to link the theorems of Rockafellar and Hiai-Umegaki with the one of Bouchitté-Valadier. We give an application to relaxation of nonconvex geometric integrals of Calculus of Variations.Received: 20 March 2002, Accepted: 12 March 2003, Published online: 16 May 2003 相似文献
33.
Jean-Philippe Uzan 《General Relativity and Gravitation》2007,39(3):307-342
Using a general classification of dark enegy models in four classes, we discuss the complementarity of cosmological observations
to tackle down the physics beyond the acceleration of our universe. We discuss the tests distinguishing the four classes and
then focus on the dynamics of the perturbations in the Newtonian regime. We also exhibit explicitely models that have identical
predictions for a subset of observations. 相似文献
34.
Jean-Philippe Bartier 《Journal of Functional Analysis》2008,254(3):851-878
Qualitative properties of non-negative solutions to a quasilinear degenerate parabolic equation with an absorption term depending solely on the gradient are shown, providing information on the competition between the nonlinear diffusion and the nonlinear absorption. In particular, the limit as t→∞ of the L1-norm of integrable solutions is identified, together with the rate of expansion of the support for compactly supported initial data. The persistence of dead cores is also shown. The proof of these results strongly relies on gradient estimates which are first established. 相似文献
35.
Jean-Philippe Uzan 《General Relativity and Gravitation》2010,42(9):2219-2246
While tested to a high level of accuracy in the Solar system, general relativity is under the spotlight of both theoreticians
and observers on larger scales, mainly because of the need to introduce dark matter and dark energy in the cosmological model.
This text reviews the main tests of general relativity focusing on the large scale structure and more particularly weak lensing.
The complementarity with other tests (including those on Solar system scales and the equivalence principle) is discussed. 相似文献
36.
Laurent Drouet Alain Haurie Francesco Moresino Jean-Philippe Vial Marc Vielle Laurent Viguier 《Computational Management Science》2008,5(1-2):119-140
This paper proposes a computational game-theoretic model for the international negotiations that should take place at the
end of the period covered by the Kyoto protocol. These negotiations could lead to a self-enforcing agreement on a burden sharing
scheme given the necessary global emissions limit that will be imposed when the real extent of climate change is known. The
model assumes a non-cooperative behavior of the parties except for the fact that they will be collectively committed to reach
a target on total cumulative emissions by the year 2050. The concept of normalized equilibrium, introduced by J.B. Rosen for
concave games with coupled constraints, is used to characterize a family of dynamic equilibrium solutions in an m-player game where the agents are (groups of) countries and the payoffs are the welfare gains obtained from a Computable General
Equilibrium (CGE) model. The model deals with the uncertainty about climate sensitivity by computing an S-adapted equilibrium. These equilibria are computed using an oracle-based method permitting an implicit definition of the
payoffs to the different players, obtained through simulations performed with the global CGE model GEMINI-E3.
Partly supported by GICC (French Ministry of Ecology), TOCSIN (EU-044287) and the Swiss-NSF NCCR-Climate program of the Swiss
NSF. For helpful comments and discussions, we thank A. Bernard, P. Thalmann, and the anonymous referee. 相似文献
37.
Gaëlle Semard Valerie Peulon-Agasse Auguste Bruchet Jean-Philippe Bouillon Pascal Cardinaël 《Journal of chromatography. A》2010,1217(33):5449-5454
It is important to develop methods of optimizing the selection of column sets and operating conditions for comprehensive two-dimensional gas chromatography. A new method for the calculation of the percentage of separation space used was developed using Delaunay's triangulation algorithms (convex hull). This approach was compared with an existing method and showed better precision and accuracy. It was successfully applied to the selection of the most convenient column set and the geometrical parameters of second column for the analysis of 49 target compounds in wastewater. 相似文献
38.
Jasmin J. Thevaril 《Solid State Communications》2011,151(9):730-733
We aim to explore the role that conduction band tail states play in shaping the optical response of hydrogenated amorphous silicon. We do so within the framework of an empirical model for the valence band and conduction band density of states functions, one that considers valence band band, valence band tail, conduction band band, and conduction band tail states. We examine the sensitivity of the joint density of states function to variations in the conduction band tail breadth, all other parameters being held fixed at their nominal hydrogenated amorphous silicon values. We find that when the conduction band tail is narrower than the valence band tail, its role in shaping the corresponding spectral dependence of the joint density of states function is relatively minor. This justifies the use of a simplified empirical model for the density of states functions that neglects the presence of the conduction band tail states in the characterization of the optical response of this material. Experimental data corresponding to hydrogenated amorphous silicon, demonstrating that the conduction band tail breadth is always less than the valence band tail breadth for this material, is then presented. Finally, fundamental reasons for the observed asymmetry in the band tail breadths are reviewed. 相似文献
39.
We give a short proof of Wolff–Denjoy theorem for (not necessarily smooth) strictly convex domains. With similar techniques we are also able to prove a Wolff–Denjoy theorem for weakly convex domains, again without any smoothness assumption on the boundary. 相似文献
40.
The starane herbicide was spectrophotometrically determined by the diazotization method in a flow injection assembly. Since starane is a substituted pyridyl compound the NH2 group at the p-position was exploited for diazotization. Starane was diazotized with nitrite and the diazotized product is coupled with beta-naphthol. The absorbance of the resulting azo dye was measured at 395 nm with a molar absorptivity of 1.5 x 10(4) L mol(-1) cm(-1). The calibration graph was linear over the range of 0.6 to 10 microg/mL, with a relative standard deviation (RSD) of 1.67% and a sampling through put of 60 samples h(-1). The % recovery for the determination of starane was found to be 96%. The method was successfully applied to the determination of the active ingredient of starane herbicide in its formulation as well as in food samples. 相似文献