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191.
Coulomb systems in which the particles interact through thed-dimensional Coulomb potential but are confined in a flat manifold of dimensiond–1 are considered. The actual Coulomb potential acting is defined by particular boundary conditions involving a characteristic macroscopic distanceW in the direction perpendicular to the manifold: either it is periodic of periodW in that direction, or it vanishes on one ideal conductor wall parallel to the manifold at a distanceW from it, or it vanishes on two parallel walls at a distanceW from each other with the manifold equidistant from them. Under the assumptions that classical equilibrium statistical mechanics is applicable and that the system has the macroscopic properties of a conductor, it is shown that the suitably smoothed charge correlation function is universal, and that the free energy and the grand potential have universal dependences onW (universal means independent of the microscopic detail). The casesd=2 are discussed in detail, and the generic results are checked on an exactly solvable model. The cased=3 of a plane parallel to an ideal conductor is also explicitly worked out.Laboratoire associé au Centre National de la Recherche Scientifique-URA D0063. 相似文献
192.
James V. Crivello 《Journal of polymer science. Part A, Polymer chemistry》2007,45(18):4331-4340
The irradiation of hybrid photopolymer systems consisting of a free radically polymerizable multifunctional acrylate monomer and a cationically polymerizable epoxide or oxetane monomer was conducted under conditions where only the free radical polymerization takes place. This results in the formation of a free‐standing polyacrylate network film containing quiescent oxonium ions along with the unreacted cyclic ether monomer. The subsequent application of a point source of heat to the film ignites a cationic ring‐opening frontal polymerization that emanates from that site and propagates to all portions of the irradiated sample. This article examines the impact of various molecular structural and experimental parameters on these novel hybrid frontal polymerizations that produce interpenetrating network polymers. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4331–4340, 2007 相似文献
193.
E. D. Mishina N. É. Sherstyuk V. O. Val’dner A. V. Mishina K. A. Vorotilov V. A. Vasil’ev A. S. Sigov M. P. De Santo E. Cazzanelli R. Barberi Th. Rasing 《Physics of the Solid State》2006,48(6):1210-1213
Ferroelectric composite two-dimensional ferroelectric/aluminum oxide nanostructures were studied. A porous aluminum oxide matrix was used as a template into which a ferroelectric precursor was introduced, followed by annealing. The prepared nanostructures were studied using optical second harmonic generation and micro-Raman scattering. 相似文献
194.
A general method for solving the problem of quantization of a top is proposed that allows for finding the Hamiltonian eigenfunctions in the form of polynomials of various degree n in the Cartesian coordinates with the use of the Lamé functions. All three coordinates x, y, and z are equivalently involved in computations, as well as their relations with ellipsoidal coordinates, which makes the computations symmetric. 相似文献
195.
Contaminant uranium poses unique problems for decontamination of former weapons processing and nuclear power facilities, as well as chemical plants, waste storage sites and former mining facilities. In addition, dealing with the possibility of intentional (i.e., a terrorist act) or accidental release of radioactive material in a populated area requires an accurate understanding of the nature of the association of such material with structural surfaces. These surfaces must also be considered in the context of repeated contamination, and the importance of atmospheric exposure, interaction with other possible contaminants, and corrosion or surface degradation due to such exposure must be taken into account. Complementary spectroscopic techniques, especially surface spectroscopies, are essential in developing models for the interaction of contaminants with surfaces and interfaces. In this review (which also presents new data on uranium association with corroding steel surfaces), we collect models of this association as determined by spectroscopic techniques, assess the important considerations in the development of more accurate models, and address some of the questions which remain. 相似文献
196.
197.
198.
We investigate the existence and stability of solutions for higher-order two-point boundary value problems in case the differential
operator is not necessarily positive definite, i.e. with superlinear nonlinearities. We write an abstract realization of the
Dirichlet problem and provide abstract existence and stability results which are further applied to concrete problems. 相似文献
199.
C. P. Massarolo G. P. Menzala A. F. Pazoto 《Mathematical Methods in the Applied Sciences》2007,30(12):1419-1435
The aim of this work is to consider the Korteweg–de Vries equation in a finite interval with a very weak localized dissipation namely the H?1‐norm. Our main result says that the total energy decays locally uniform at an exponential rate. Our analysis improves earlier works on the subject (Q. Appl. Math. 2002; LX (1):111–129; ESAIM Control Optim. Calculus Variations 2005; 11 (3):473–486) and gives a satisfactory answer to a problem suggested in (Q. Appl. Math. 2002; LX (1):111–129). Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
200.
P. De Maesschalck 《Journal of Differential Equations》2007,238(2):338-365
By applying geometric techniques to real analytic singularly perturbed vector fields on the plane, we develop a way to give a bound on the Gevrey type of the Taylor development of canard manifolds at degenerate planar turning points. By blowing up the phase space at the turning point, we find asymptotic estimates even when such expansions w.r.t. traditional phase space variables do not exist. The asymptotic estimates are then used to give a sufficient and necessary condition on the existence of (local) canard solutions. 相似文献