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51.
On Traveling Wave Fronts in a Bacterial Growth Model with Density-Dependent Diffusion and Chemotaxis
M. B. A. Mansour 《Journal of statistical physics》2011,143(1):197-204
Bacterial colonies often generate patterns that are characterized by fingerlike projections growing out of the propagating
front. In this paper, we analyze the traveling wave fronts in bacterial growth model that accounts for chemotactic movement
as well as random motion in density-dependent diffusion. Specifically, the existence of traveling wave solutions to model
equations is examined by means of methods of local linear and nonlinear analysis, and numerical simulations. The occurrence
is shown of both sharp and smooth traveling wave fronts. 相似文献
52.
In this work, forced convective heat transfer of nanofluid in the developing laminar flow (entrance region) in a circular tube is considered. The nanofluid thermal conductivity, as an important parameter, is considered as two parts: static and dynamic part. Simulated results show that the dynamic part of nanofluid thermal conductivity due to the Brownian motion has a minor effect on the heat transfer coefficients, on the other hand, static part of thermal conductivity including nanolayer around nanoparticle has an important role in heat transfer. 相似文献
53.
In this paper, the approximate controllability of neutral stochastic fractional differential equations involving nonlocal initial conditions is studied. By using Sadovskii’s fixed point theorem with stochastic analysis theory, we derive a new set of sufficient conditions for the approximate controllability of semilinear fractional stochastic differential equations with nonlocal conditions under the assumption that the corresponding linear system is approximately controllable. Finally, an application to a fractional partial stochastic differential equation with nonlocal initial condition is provided to illustrate the obtained theory. 相似文献
54.
Tarek S. Mansour 《合成通讯》2013,43(3-4):659-665
Nitrogen protected amino acid imidazolides undergo facile carbon acylation with magnesium p-nitrobenzylmalonate dihydrate in THF to give pseudodipeptides in 30-79% isolated yield. 相似文献
55.
56.
Experiments on two-dimensional fluidized beds of glass beads are presented for two fluids of typical Reynolds numbers of about 1 and a few hundred. The presence of inertial effects leads to the formation of wakes behind the particles and consequently to an anisotropy of the microstructure. The microstructures, studied by video imaging, are characterized by pair probability distribution functions and structure factors. 相似文献
57.
Toufik Mansour 《Letters in Mathematical Physics》2009,87(1-2):1-18
A q-analogue of the polylogarithm function is introduced via a consideration of the spectral zeta-function of the quantum group SU q (2). We derive certain identities for linear and non-linear combinations of the q-analogue of polylogarithm functions with negative exponents. 相似文献
58.
A nonsimilar boundary layer analysis has been presented for the free convection along a vertical plate embedded in a fluid-saturated
porous medium in the presence of surface mass transfer and internal heat generation. The transformed conservation laws are
solved numerically for the cases of variable wall temperature and variable wall heat flux boundary conditions. Results are
presented for the details of the velocity and temperature fields as well as Nusselt number.
Received on 13 December 1996 相似文献
59.
The nuclear behaviour at high angular momenta is studied by γ-rays emitted in (HI, Xn) reaction. The study of very-high spin states in 153Ho via discrete-line γ-ray spectroscopy and a comparison between the partial decay schemes of 153Ho and the neighbouring 152Dy and 154Er nuclei are discussed in the context of the high spin structure. Second, we present comments on some phenomena observed at high spin states in 153Ho and 152Dy nuclei. 相似文献
60.
A boundary layer analysis has been presented for the interaction of mixed convection with thermal radiation in laminar boundary flow from a vertical wedge in a porous medium saturated with a power-law type non-Newtonian incorporating the variation of permeability and thermal conductivity. The transformed conservation laws are solved numerically for the case of variable surface temperature conditions. The combined convection non-similar parameter we note that =0 and 1 correspond to pure free and forced convection cases. The Rosseland approximation is used to describe the radiative heat flux in energy equation. Velocity and temperature profiles as well as the local Nusselt number are presented. 相似文献