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11.
All-optical programmable shaping of narrow-band nanosecond pulses with picosecond accuracy by use of adapted chirps and quadratic nonlinearities 总被引:1,自引:0,他引:1
We experimentally demonstrate pure optical pulse picosecond shaping of narrow-bandwidth nanosecond pulses. The method used is based on the manipulation in the spectral domain of strongly chirped femtosecond pulses and on the use of either frequency addition or frequency difference. 相似文献
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B. Raoult J. Farges M. F. De Feraudy G. Torchet 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1989,12(1-4):85-87
We present a study of the stability of clusters models made of a numberN of atoms in the range 500 to 6000 atoms, freely interacting through the Lennard-Jones potential. The potential energy per atom, calculated for relaxed models, shows that stable models belong to an icosahedral sequence whenN<1600 and to a decahedral sequence beyond. A coexistence size range of both structures is discussed in connection with experimental results on argon clusters in free jet expansions. 相似文献
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In the recent years, lattice modelling proved to be a topic of renewed interest. Indeed, fields as distant as chemical modelling
and biological tissue modelling use network models that appeal to similar equilibrium laws. In both cases, obtaining an equivalent
continuous model allows to simplify numerical procedures. We define the basic properties of lattices: elasticity, frame-indifference,
hyperelasticity. We determine rigorously the form that constitutive laws undertake under frame-indifference and hyperelasticity
assumptions. Finally, we describe an homogenization technique designed for discrete structures that provides a limit continuum
mechanics model and, in the special case of hexagonal lattices, we investigate the symmetry properties of the limit constitutive
law.
相似文献
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Let F be a distribution function in the domain of attraction of an extreme value distribution
. In case 0 and F has an infinite end-point, we study the asymptotic behaviour of the relative approximation error
of a high quantile
such that
, where the order tends to 0. We use the approximation of the excesses over a high threshold u by a Generalized Pareto distribution. We give sufficient conditions under which
tends to 0.AMS 2000 Subject Classification Primary—60G70, Secondary—62G20, 62G32 相似文献
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B. Vâlcu I.F. Schneider M. Raoult C. Strömholm M. Larsson A. Suzor-Weiner 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1998,1(1):71-78
The effect of rotational interaction in the low energy dissociative recombination process of diatomic molecules has been explored
for typical molecular ions () which sample a large range of molecular masses. We show that rotation plays a role mainly for the indirect recombination
process through bound Rydberg states, and for light molecules. When the direct process based on a strong electronic interaction
is fast and dominating, rotational couplings can be safely neglected especially for heavier molecules like NO.
Received: 18 September 1997 / Revised in final form: 17 October 1997 / Accepted: 20 October 1997 相似文献
17.
Emmanuel Maitre Thomas Milcent Georges-Henri Cottet Annie Raoult Yves Usson 《Mathematical and Computer Modelling》2009,49(11-12):2161-2169
We describe in this paper two applications of Eulerian level set methods to fluid-structure problems arising in biophysics. The first one is concerned with three-dimensional equilibrium shapes of phospholipidic vesicles. This is a complex problem, which can be recast as the minimization of the curvature energy of an immersed elastic membrane, under a constant area constraint. The second deals with isolated cardiomyocyte contraction. This problem corresponds to a generic incompressible fluid-structure coupling between an elastic body and a fluid. By the choice of these two quite different situations, we aim to bring evidence that Eulerian methods provide efficient and flexible computational tools in biophysics applications. 相似文献
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We characterize the macroscopic effective behavior of a graphene sheet modeled by a hexagonal lattice of elastic bars, using Γ-convergence. 相似文献