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91.
We prove analogs of the Telyakovskii-Pochuev criteria for multipliers of uniform convergence and of convergence in the integral metric for multiplicative systems with bounded generating sequence. 相似文献
92.
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
93.
Bang-yen Chen 《Annals of Global Analysis and Geometry》1993,11(4):345-359
In this article we obtain the best possible estimates of the type number of tensor product immersions and investigate tensor product immersions with lowest possible type. Several classification theorems in this respect are then proved. 相似文献
94.
Ph. Choquard B. Piller R. Rentsch P. Vieillefosse 《Journal of statistical physics》1989,55(5-6):1185-1262
We report analytical and numerical studies of surface correlations in finite, homogeneously polarizable, classical Coulomb systems placed in an insulating or conducting environment. Their purpose is to understand the phenomenological, shape-dependent laws of electrostatics, from the point of view of statistical mechanics; we focus on the knowledge of the dielectric susceptibility of the system, a quantity proportional to the equilibrium fluctuation of the system's instantaneous polarization per unit volume. This goal has been achieved for a system in a conducting state. The picture is that the shape-dependent part of the susceptibilities results from the action of unbounded observables (the second moments of the instantaneous polarization of the system) on long-range surface correlations and that the relations of electrostatics are verified by means of shape-dependent thermodynamic limits. This picture is supported (i) by exact solutions and asymptotic analysis of the Debye-Hückel approximation of multicomponent plasmas in disks and spheres with insulating and conducting environment and also in ellipses in a vacuum, and (ii) by computer simulations of a one-component plasma in a disk with different environments, notably a conducting environment with permeable and impermeable wall. These observations have revealed for the first time the reason why the susceptibility of a conducting disk in a conductor with impermeable walls diverges linearly with the radius of the disk: this is due to the occurrence of long-range radial correlations in the conductor. These findings are quantitatively interpreted in terms of a novel canonical Debye-Huckel approximation as contrasted to the ordinary grand canonical version. Lastly a fresh look at the problem of the surface correlations of a conductor in a vacuum, which places the observer close to the surface of the conductor but in the vacuum, is presented and applied to the disk, the ellipse, the cylinder, the sphere, and the wedge. 相似文献
95.
Ar—Kr溶液扩散系数的分子动力学模拟及其与温度的关系 总被引:2,自引:1,他引:2
用分子动力学模拟方法研究确定Ar-Kr溶液的自扩散系数D1、D2和互扩散系数D12以及它们随温度变化的规律。结果表明,分别用Green-Kubo法和Einstein法得到的扩散系数在数值上一致;该溶液的3种扩散系数均满足D=D0e^E/RT关系。 相似文献
96.
A new series of acrylates with the same mesogens containing thioester as bridge-bondwere synthesized, and the acrylates were characterized by H~1 NMR, IR and MS. Thepolymers were obtained by radical polymerization using AIBN as initiator. The monomersand polymers exhibit thermotropic-enantiotropic liquid crystalline behavior. 相似文献
97.
In this review paper, the NBS scale and its limitations are briefly discussed. The magnitude of liquid junction potentials and some calculated values are presented. The use of a molality scale for hydrogen electrode concentration cells at high temperatures is described, and results from measurements on ionization equilibria are summarized. Use of this scale is also recommended for certain circumstances with cells without liquid junction. As an alternative activity scale, use of the Pitzer ion-interaction treatment for ions is recommended for special cases. Finally, reference data are presented for ±HCl in HCl(aq) to 350°C and (HCl+NaCl)(aq) to 200°C that were derived by use of the Pitzer ion-interaction treatment.Presented at the Second International Symposium on Chemistry in High Temperature Water, Provo, UT, August 1991. 相似文献
98.
99.
Rat V. André P. Aubreton J. Elchinger M.F. Fauchais P. Lefort A. 《Plasma Chemistry and Plasma Processing》2002,22(4):453-474
The calculation of two-temperature transport coefficients in an argon–hydrogen plasma at atmospheric pressure is performed using a new theory of two-temperature transport properties recently presented. The latter takes into account the coupling between electrons and heavy species, coupling neglected in the already existing theories of Devoto and Bonnefoi. Transport coefficients are calculated at two-temperatures, the kinetic temperature of electrons Te being different from that of heavy species Th. This paper is divided into two parts. The first one is related to elastic processes and its aim is to compare the results obtained with this new theory for viscosity , translational thermal conductivities tr
e and tr
h and electrical conductivity with the previous results of Bonnefoi. The composition is calculated with the modified equilibrium constant of van de Sanden et al. and the most recent interaction potential are discussed. As it could be expected the electron translational thermal conductivity and the electrical conductivity calculated when taking into account or not the coupling between electrons and heavy species show non-negligible discrepancies. Besides this comparison, the results also show the drastic influence of the non-equilibrium parameter =Te/Th on the values of , , tr
e, and tr
h. 相似文献
100.
TONG Hua-Nan ZHANG Hao CHENG Wen-Dan WU Dong-Sheng GONG Ya-Jing ZHU Jing HUANG Shu-Ping ZHAO Dan 《结构化学》2007,26(3)
The single crystal and crystallized powder of triphosphate CeP3O9 have been synthesized, and the space group of CeP3O9 has been determined to be C2221 with the cell parameters ofa = 8.6059, b = 11.2437, c = 7.3518 (A), V= 711.4(3) (A)3, Z= 4, Dc = 3.520 g/cm3, F(000) = 700,R = 0.0377 and wR = 0.0930. The absorption and emission spectra have been measured, for which the strongest absorption and emission peaks are located at 280 and 320 nm, respectively. The density of state (DOS) and dielectric function have been calculated by the DFT method. The crystal is transparent provided the wavelength is larger than 341 nm, and the observed ultraviolet cut-off edge is at about 350 nm for a polycrystalline power sample. It is possible that the triphosphate CeP3O9 will become an ultraviolet emission material. 相似文献