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21.
Ph. Laurent M. Abgrall Ch. Jentsch P. Lemonde G. Santarelli A. Clairon I. Maksimovic S. Bize Ch. Salomon D. Blonde J.F. Vega O. Grosjean F. Picard M. Saccoccio M. Chaubet N. Ladiette L. Guillet I. Zenone Ch. Delaroche Ch. Sirmain 《Applied physics. B, Lasers and optics》2006,84(4):683-690
In this paper we describe the cold atom clock PHARAO, designed for microgravity operation. All elements of the PHARAO engineering model have been manufactured and delivered to CNES, the French space agency. We present the clock design, its main characteristics, and initial science operation. PHARAO is one of the main components of the Atomic Clock Ensemble in Space payload that is scheduled to fly on board the International Space Station in 2010. PACS 07.87.+v; 06.30.Ft; 95.55.Sh; 32.80.Pj 相似文献
22.
The synthesis of indole ring-fused benzazepinone series as latonduine derivatives has been developed via an intramolecular Heck reaction. The scope has been enlarged not only to indole moiety but also to pyrrolo and benzo[b]thiophene nuclei. Several derivatives prepared have been evaluated in vitro for their antiproliferative activities on breast cancer cell lines. Some of them showed promising cytotoxic activities. 相似文献
23.
24.
We describe links between a recently introduced semidefinite relaxation for the max-cut problem and the well known semidefinite
relaxation for the stable set problem underlying the Lovász’s theta function. It turns out that the connection between the
convex bodies defining the semidefinite relaxations mimics the connection existing between the corresponding polyhedra. We
also show how the semidefinite relaxations can be combined with the classical linear relaxations in order to obtain tighter
relaxations.
This work was done while the author visited CWI, Amsterdam, The Netherlands.
Svata Poljak untimely deceased in April 1995. We shall both miss Svata very much. Svata was an excellent colleague, from whom
we learned a lot of mathematics and with whom working was always a very enjoyable experience; above all, Svata was a very
nice person and a close friend of us.
The research was partly done while the author visited CWI, Amsterdam, in October 1994 with a grant fom the Stieltjes Institute,
whose support is gratefully acknowledged. Partially supported also by GACR 0519.
Research support by Christian Doppler Laboratorium für Diskrete Optimierung. 相似文献
25.
Laurent Moret-Bailly 《Journal of Number Theory》2003,99(2):383-404
We give criteria for R-equivalence of torsors under finite constant group schemes over a field. In particular, using bitorsors, we obtain a Galois dévissage result which formalises and generalises a theorem of Philippe Gille in the case of local fields; for instance, Gille's theorem is shown to extend to higher local fields. 相似文献
26.
Laurent Gardes 《Comptes Rendus Mathematique》2003,337(4):287-292
The purpose of this Note is to propose an estimator of the extreme value index constructed by using only the number of points exceeding random thresholds. We prove the weak consistency and the asymptotic normality of this estimator. We deduce from this last result that the rate of convergence of our estimator is in a power of the sample size. To our knowledge, this rate of convergence is not reached by any other estimate of the extreme value index. Through a simulation, we compare our estimator to the moment estimator (Dekkers et al., Ann. Statist. 17 (1989) 1833–1855). To cite this article: L. Gardes, C. R. Acad. Sci. Paris, Ser. I 337 (2003). 相似文献
27.
Laurent Bartholdi 《Comptes Rendus Mathematique》2003,336(7):549-554
This Note constructs a finitely generated group W whose word-growth is exponential, but for which the infimum of the growth rates over all finite generating sets is 1 – in other words, of non-uniformly exponential growth.This answers a question by Mikhael Gromov (Structures métriques pour les variétés riemanniennes, in: J. Lafontaine, P. Pansu (Eds.), CEDIC, Paris, 1981).The construction also yields a group of intermediate growth V that locally resembles W in that (by changing the generating set of W) there are isomorphic balls of arbitrarily large radius in V and W's Cayley graphs. To cite this article: L. Bartholdi, C. R. Acad. Sci. Paris, Ser. I 336 (2003). 相似文献
28.
Laurent Charles 《Communications in Mathematical Physics》2003,239(1-2):1-28
This article is devoted to the Toeplitz Operators [4] in the context of the geometric quantization [11, 15]. We propose an ansatz for their Schwartz kernel. From this, we deduce the main known properties of the principal symbol of these operators and obtain new results : we define their covariant and contravariant symbols, which are full symbols, and compute the product of these symbols in terms of the Kähler metric. This gives canonical star products on the Kählerian manifolds. This ansatz is also useful to introduce the notion of microsupport. 相似文献
29.
Lionel Joucla Florence Popowycz Olivier Lozach Laurent Meijer Benoît Joseph 《Helvetica chimica acta》2007,90(4):753-763
The syntheses of paullone ( 1a ) and three paullone derivatives, including a sulfur analogue ( 2a ), a tricyclic derivative ( 2b ), and a ring‐enlarged variant ( 2c ), are described, Pd‐catalyzed intramolecular Heck reaction being the key step. The kinase‐inhibitory properties of the novel paullone analogues were investigated. 相似文献
30.
The convergence of iterative based domain decomposition methods is linked with the absorbing boundary conditions defined on the interface between the sub-domains. For linear elasticity problems, the optimal absorbing boundary conditions are associated with non-local Dirichlet-to-Neumann maps. Most of the methods to approximate these non-local maps are based on a continuous analysis. In this paper, an original algebraic technique based on the computation of local Dirichlet-to-Neumann maps is investigated. Numerical experiments are presented for linear elasticity problems with extreme contrasts in the coefficients. 相似文献