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61.
Bernard Pinchuk 《Israel Journal of Mathematics》1974,17(1):105-107
Sharp bounds for general integral means of analytic functions in the unit disc are determined. These bounds depend only on the moduli of the points on the boundary of the image domain nearest to and farthest from the origin. The proof is shown to be a simple application of a deep theorem of A. Beurling in potential theory. 相似文献
62.
A. Salmoun R. Brédy J. Bernard L. Chen S. Martin 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,47(1):55-61
Electron capture processes in collision between slow
X7+ (X = N, O and Ne) ions and C60 fullerene have been
investigated using coincident measurements of the number n of ejected
electrons, the mass and charge of the multicharged C60
r+ recoil ions and their fragments Cm
i+ and the final charge state of the
outgoing projectiles X(q-s)+ (
). The
collision velocity is about 0.4 a.u. The partial cross-sections σr
s , corresponding to r electrons transferred to the projectile with only s electrons stabilized, have been measured. Cross-sections
for collisions “inside” and those “outside” the C60
cage have been separated by analyzing the kinetic energy of the outgoing
projectile. The mean final charge state for frontal collisions has been
measured to 3.1, 2.6 and 2.5 for N7+, O7+ and Ne7+
respectively. These results show the importance of the core effect on the
stabilisation processes of captured electrons. 相似文献
63.
Photophysics of Calix[4]biscrown-Based Ditopic Receptors of Caesium Containing One or Two Dioxocoumarin Fluorophores 总被引:1,自引:0,他引:1
The ditopic receptors Calix-COU1 and Calix-COU2 consist of a calix[4]biscrown containing one or two dioxycoumarin fluorophores, respectively, inserted into the crown. They can form 1:1 and 2:1 (metal:ligand) complexes with caesium ions. The photophysical properties of the 1:1 complexes can be explained by (i) cation tunneling through the tube-shaped cavity (composed of the four phenyl rings) of the calix[4]biscrown, (ii) photodisruption of the interaction between the bound cation and the oxygen atoms belonging to both the coumarin moiety and the crown, (iii) photoinduced motions of the cation. 相似文献
64.
Manuel Bernard Ghislain Lartigue Guillaume Balarac Vincent Moureau Guillaume Puigt 《国际流体数值方法杂志》2020,92(11):1551-1583
In this article, a new framework to design high-order approximations in the context of node-centered finite volumes on simplicial meshes is proposed. The major novelty of this method is that it relies on very simple and compact differential operators, which is a critical point to achieve good performances in the High-performance computing context. This method is based on deconvolution between nodal and volume-average values, which can be conducted to any order. The interest of the new method is illustrated through three different applications: mesh-to-mesh interpolation, levelset curvature computation, and numerical scheme for convection. Higher order can also be achieved within the present framework by introducing high-rank tensors. Although these tensors feature much symmetries, their manipulation can quickly become an overwhelming task. For this reason and without loss of generality, the present articles are limited to third-order expansion. This method, although tightly connected to the k-exact schemes theory, does not rely on successive corrections: the high-order property is obtained in a single operation, which makes them more attractive in terms of performances. 相似文献
65.
Detailed numerical computations of thermal lensing in optically transmitting materials are carried out. The time evolution of the transmitted beam intensity, revealing defocusing and degradation effects, is displayed for a variety of materials, under a variety of geometrical configurations and operating conditions. While the degradation is monotonic with increasing time or incident power for materials with small induced birefringence, it may display an oscillatory character when birefringence effects are large. From the intensity degradation, criteria are formulated for rating optical performance of materials under transient and steady-state conditions. Ratings are obtained for a variety of transmitting materials at 10.6 μm. As a class, ionic materials are found to substantially outperform semiconductors and glasses at 10.6 μm. 相似文献
66.
The ASED-MO method has been used to gather electronic and energetic information on Pd deposits on Ni(111) and Pd atom inclusion in the first Ni layer since these model catalysts exhibit a striking catalytic efficiency towards butadiene hydrogenation. The electronic structure of Pd atoms is strongly altered compared with pure Pd. A Pd(4d)→Pd(5s) electronic transfer occurs in the case of the deposit when a slight similar transfer and a charge transfer from Pd to surrounding Ni takes place in the case of the inclusion. Those results are consistent with XPS experimental data. A low density of states, near the Fermi level, is also observed. The optimal geometrical situation for Pd deposits is found to be 2D-aggregates (in pseudoepitaxy or pseudomorphy with the underlying Ni surface, depending on the aggregate size). Small aggregates (part of the first Ni layer) are found to be the most stable in the case of a Pd inclusion in the Ni with a Pd---Pd distance of 2.64 Å, in agreement with available EXAFS experimental data. 相似文献
67.
François Bentosela Horia D. Cornean Bernard H. Fleury Nicola Marchetti 《Mathematical Methods in the Applied Sciences》2011,34(8):963-976
We develop a deterministic ab initio model for the input–output relationship of a multiple‐input multiple‐output (MIMO) wireless channel, starting from the Maxwell equations combined with Ohm's law. The main technical tools are scattering and geometric perturbation theories. The derived relationship can lead us to a deep understanding of how the propagation conditions and the coupling effects between the elements of multiple‐element arrays affect the properties of an MIMO channel, e.g. its capacity and its number of degrees of freedom. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
68.
Bernard Ancian Olivier Bernard Jean Chevalet Vincent Dahirel Didier Devilliers Emmanuelle Dubois 《Molecular physics》2014,112(9-10):1213-1221
Pierre Turq has made decisive contributions to the theory and to the multiscale simulation of charged systems, such as molten salts, electrolyte solutions and colloidal suspensions, in the bulk, at interfaces and under confinement. His research line focussed on dynamical properties and was characterised by constant efforts to connect his theoretical work to both experiments and practical applications. In this article, his colleagues and former students pay a tribute to his past and current research interests by illustrating some recent developments accomplished in his laboratory. 相似文献
69.
70.
We address the question of determining the eigenvalues \({\lambda_{n}}\) (listed in nondecreasing order, with multiplicities) for which Courant’s nodal domain theorem is sharp i.e., for which there exists an associated eigenfunction with \({n}\) nodal domains (Courant-sharp eigenvalues). Following ideas going back to Pleijel (1956), we prove that the only Courant-sharp eigenvalues of the flat equilateral torus are the first and second, and that the only Courant-sharp Dirichlet eigenvalues of the equilateral triangle are the first, second, and fourth eigenvalues. In the last section we sketch similar results for the right-angled isosceles triangle and for the hemiequilateral triangle. 相似文献