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41.
We consider the linear equation of state for matter distributions that may be applied to strange stars with quark matter.
In our general approach the compact relativistic body allows for anisotropic pressures in the presence of the electromagnetic
field. New exact solutions are found to the Einstein-Maxwell system. A particular case is shown to be regular at the stellar
centre. In the isotropic limit we regain the general relativistic isothermal Universe. We show that the mass corresponds to
the values obtained previously for quark stars when anisotropy and charge are present.
相似文献
42.
Pierre Gaillard 《理论物理通讯》2014,61(3):365-369
We construct here explicitly new deformations of the Peregrine breather of order 5 with 8 real parameters. This gives new families of quasi-rational solutions of the NLS equation and thus one can describe in a more precise way the phenomena of appearance of multi rogue waves. With this method, we construct new patterns of different types of rogue waves. We get at the same time, the triangular configurations as well as rings isolated. Moreover, one sees appearing for certain values of the parameters, new configurations of concentric rings. 相似文献
43.
This paper deals with the study of the effect of MHD on thin films of a micropolar fluid. These thin films are considered for three different geometries, namely: (i) flow down an inclined plane, (ii) flow on a moving belt and (iii) flow down a vertical cylinder. The transformed boundary layer governing equations of a micropolar fluid and the resulting system of coupled non-linear ordinary differential equations are solved numerically by using shooting method. Numerical results were presented for velocity and micro-rotation profiles within the boundary layer for different parameters of the problem including micropolar fluid parameters, magnetic field parameter, etc., which are also discussed numerically and illustrated graphically. 相似文献
44.
Motzkin numbers are derived from a special case of Random Domino Automaton – recently proposed a slowly driven system being a stochastic toy model of earthquakes. It is also a generalisation of 1D Drossel–Schwabl forest-fire model. A solution of the set of equations describing stationary state of Random Domino Automaton in inverse-power case is presented. A link with Motzkin numbers allows to present explicit form of asymptotic behaviour of the automaton. 相似文献
45.
We present exact solutions for the position-dependent mass Schrödinger equation (PDMSE) in an annular billiard with impenetrable walls where the mass is allowed to depend on the radial position, i.e., μ=μ(r). Exact wavefunctions are calculated explicitly for four mass distributions. 相似文献
46.
By means of the classical symmetry method, we investigate two types of the (2+1)-dimensional nonlinear Klein-Gorden equation. For the wave equation, we give out its symmetry group analysis in detail. For the second type of the (2+1)-dimensional nonlinear Klein-Gorden equation, an optimal system of its one-dimensional subalgebras is constructed and some corresponding two-dimensional symmetry reductions are obtained. 相似文献
47.
G. Cazzolli S. Caponi A. Defant C. M. C. Gambi S. Marchetti M. Mattarelli M. Montagna B. Rossi F. Rossi G. Viliani 《Journal of Raman spectroscopy : JRS》2012,43(12):1877-1883
Ionic surfactants such as sodium dodecyl sulfate (SDS) belong to the amphiphile family: they possess a long hydrophobic hydrocarbon chain and a polar hydrophilic headgroup. In a polar solvent and over the critical micellar concentration these molecules join to form micelles. The micellar solutions, in turn, if doped with various ligands tend to aggregate. Solid SDS, micelles of SDS in water and micelles of SDS doped with two types of macrocyclic ligands, Kryptofix 2.2.2 (K222) and crown ether 18‐Crown‐6 (18C6), at different concentrations are studied by Raman scattering, that represents a new approach to such systems. The experimental Raman spectrum, obtained on crystalline powders of SDS, is compared with the ab initio computed spectrum in order to assign the vibrational bands. After discriminating sensitive peaks by comparing the crystalline powders of the single components and their water solutions, the aggregation process and the action of the ligands are analyzed following the evolution of the intensity and wavenumber of these characteristic Raman peaks. This shows that Raman spectroscopy is sensitive to the aggregation dynamics and to the effects induced by the hydration layer on the molecules in solutions. A saturation effect in the aggregation process with the increase of the ligand concentration is observed. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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The constructive technique and its application in solving a nonlinear reaction diffusion equation 下载免费PDF全文
A mathematical technique based on the consideration of a nonlinear
partial differential equation together with an additional condition
in the form of an ordinary differential equation is employed to
study a nonlinear reaction diffusion equation which describes a real
process in physics and in chemistry. Several exact solutions for the
equation are acquired under certain circumstances. 相似文献