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101.
Shahpoor Moradi 《International Journal of Theoretical Physics》2009,48(4):969-980
The exact solutions of the Dirac equation are discussed for a Robertson-Walker spacetime with asymptotically Minkowskian in and out regions. We obtain the mode solutions which reduce to positive and negative Minkowskian spinors in asymptotically regions.
Using the obtained solutions we compute the density of created particles. 相似文献
102.
This paper presents a modification on the stair-shaped volume of fluid (VOF) advection algorithm called defined donating and accepting region (DDAR) scheme which shows the importance of the more accurate definition of donating and accepting region. The algorithm which is suitable for uniform Cartesian grids uses multi-dimensional method of cell boundary flux integration. The performance of the modified scheme presented here has been compared with the performance of a number of alternative schemes taking into account translation, rotation and shear advection tests. In some aspects, the DDAR scheme is shown to be more accurate than linear constant and flux limited schemes, and in some way comparable with the linear piecewise schemes (PLIC). Without using any geometrical information, DDAR scheme predicts flux correctly using information of cell volume fraction and its face velocities and consequently improves the performance the first order DDR schemes. 相似文献
103.
Somayeh Moradi 《代数通讯》2018,46(8):3377-3387
In this paper, we introduce and study families of squarefree monomial ideals called clique ideals and independence ideals that can be associated to a finite graph. A family of clique ideals with linear resolutions has been characterized. Moreover, some families of graphs for which the quotient ring of their clique ideal is Cohen–Macaulay are introduced and some homological invariants of the clique ideal of a graph G, which is the complement of a path graph or a cycle graph, are obtained. Also some algebraic properties of the independence ideal of path graphs, cycle graphs and chordal graphs are studied. 相似文献
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107.
Afshin Moradi 《Optik》2012,123(15):1343-1345
Propagation of the transverse magnetic waves along flat biological membranes are studied within the framework of the classical electrodynamics. The ionic excitations adjacent to the exterior and interior surfaces of the flat cell membranes are modeled by a quasi two-dimensional (2D) layers of counter-ions fluid which is described by means of the linearized hydrodynamic theory. Dispersion relation of the plasma wave in the system is obtained by solving Maxwell and fluid equations with appropriate boundary conditions. 相似文献
108.
The Stryjek and Vera (1986) [9] modification of Peng-Robinson (PRSV2) equation of state has been applied for modeling vapor-liquid equilibrium of the systems MTBE + methanol, MTBE + ethanol and methanol + ethanol. Binary interaction parameters for mixing rules have been estimated by using experimental data at the atmospheric pressure. The calculated binary interaction parameters were used for predicting azeotropic behavior at high pressure and also for isobaric equilibrium points which showed an excellent agreement with experimental data. In addition, estimated binary interaction parameters for binary systems were used for ternary system (MTBE + methanol + ethanol). The predictions deviated only slightly from the experimental data. The results show PRSV2 can be used for VLE prediction of polar systems. 相似文献
109.
A moisture‐ and air‐stable heterogenized palladium catalyst was synthesized by coordination of palladium with S‐propyl‐2‐aminothiobenzamide supported on Fe3O4 magnetic nanoparticles. The prepared nanocatalyst was characterized using Fourier transform infrared, energy‐dispersive X‐ray and inductively coupled plasma atomic emission spectroscopies, X‐ray diffraction, vibrating sample magnetometry, transmission and scanning electron microscopies, dynamic laser scattering and thermogravimetric analysis. This catalyst could be dispersed homogeneously in water or poly(ethylene glycol) and further applied as an excellent nano‐organometal catalyst for Suzuki and Heck reactions. The catalyst was easily separated with the assistance of an external magnet from the reaction mixture and reused for several consecutive runs without significant loss of its catalytic efficiency or palladium leaching. The leaching of catalyst was examined using hot filtration and inductively coupled plasma atomic emission spectroscopy. Also, the effects of various reaction parameters on the Suzuki and Heck reactions are discussed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
110.
Hamid Moghimi Amir Moradi Javad Hamedi Mina Basiri 《Applied biochemistry and biotechnology》2016,178(6):1207-1219