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991.
The two-dimensional boundary layer flow of an Oldroyd-B fluid in the presence of nanoparticles is investigated. Convective heat and mass conditions are considered in the presence of thermal radiation and heat generation. The Brownian motion and thermophoresis effects are retained. The nonlinear partial differential equations are reduced into the ordinary differential equation (ODE) systems. The resulting ODE systems are solved for the series solutions. The results are analyzed for various physical parameters of interest. Numerical values of the local Nusselt and Sherwood numbers are also computed and analyzed. 相似文献
992.
《Wave Motion》2015
In this paper we consider an inverse scattering problem from an open arc with impedance boundary conditions on both sides of the crack. Our aim is to recover both the impedance function and the unknown crack simultaneously from the far-field pattern with only one incident wave. Making the most out of the direct problem, a straightforward method of iterative nature is developed for the inverse problem. The ill-posedness of this problem is considered by incorporating the Tikhonov regularization. Numerical examples are provided at the end of the paper to show the feasibility of our method. 相似文献
993.
Analysis of a gravity-induced film flow of a fluid containing both nanoparticles and gyrotactic microorganisms along a convectively heated vertical surface is presented. The Buongiorno model is applied. Two kinds of boundary conditions, the passive and the active boundary conditions, are considered to investigate this film flow phenomenon. Through a set of similarity variables, the ordinary differential equations that describe the conservation of the momentum, the thermal energy, the nanoparticles, and the microorganisms are derived and then solved numerically by an efficient finite difference technique. The effects of various physical parameters on the profiles of momentum, thermal energy, nanoparticles, microorganisms, local skin friction, local Nusselt number, local wall mass flux, and local wall motile microorganisms flux are investigated. It is expected that the passively controlled nanofluid model can be much more easily achieved and applied in real circumstances than the actively controlled model. 相似文献
994.
A. F. Latypov 《Thermophysics and Aeromechanics》2009,16(2):303-313
An exergy analysis of possible regimes of energy supply to the air flow in the ramjet duct is carried out. A condition for
the supply of a given heat amount to supersonic flow and a condition of the passage across the sound velocity are obtained
for a duct with variable cross-sectional area. An analysis of the flow in a model ramjet duct at a pulsed-periodic energy
supply is carried out. For a clear demonstration of possible schemes of heat supply in such a duct, a diagram in the temperature-exergy
coordinates is proposed. A duct configuration in which the heat supply to supersonic flow is realized with regard for the
limitation of the gas static temperature is proposed. 相似文献
995.
The factors influencing the state and wetting transition of droplets on a rough surface are both complex and obscure. The
change in wetting is directly reflected by changes under the contact condition of the droplets with the surface. The recent
study about the wettability of the superhydrophobic surface under the condensing condition arouses the new understanding about
the apparent state of droplets on a rough surface. In this work, to validate the existence of droplets in an intermediate
state, a microscale pillar topological polydimethylsiloxane (PDMS) surface was manufactured and its wettability under various
conditions was studied. According to the experimental data, it is proposed that the wetting state of a rough surface may be
embodied using the contact area ratio of a solid/liquid/gas droplet with the projective plane. A general calculation model
for the apparent contact angle of droplets is given and expressed diagrammatically. It is found that the measured apparent
contact angles of droplets at different states on the surface falls within the range predicted by our proposed equation.
Supported by the National Natural Science Foundation of China (Grant No. 50606025) 相似文献
996.
In the framework of the topcolor-assisted technicolor (TC2) model, we study the production of the neutral top-pion πt0 in association with a high-pT jet al the LHC, which proceeds via the partonic processes gg→πt0g, gq→πt0q, qq→πt0g, gb(b)→πt0b(b), and bb→πt0g. We find that it is very challenging to detect the neutral top-pion πt0 via the process pp→πt0 +jet-t-X→tt +jet + X, while the possible signatures of πt0 might be detected via the process pp→πt0 +jet+X→(tc+tc)+jet+X at the LHC. 相似文献
997.
998.
中立型二阶非线性微分方程振动性的判据 总被引:7,自引:0,他引:7
Abstract. In this paper ,the oscillation criteria for the solutions of the nonlinear differential e-quations of neutral type of the forms: 相似文献
999.
Theoretical study of the electronic structure of LiNa and LiNa<Superscript>+</Superscript> molecules
Neji Khelifi Riadh Dardouri Omar Marzook Al-Dossary Brahim Oujia 《Journal of Russian Laser Research》2009,30(2):172-186
Adiabatic potential energy, spectroscopic constants, dipole moments, and vibrational levels of the lowest electronic states
of the alkali dimer LiNa molecule dissociating into Na (3s, 3p, 4s, 3d, and 4p) + Li (2s, 2p, 3s, and 3p) in 1,3Σ, 1,3Π, and 1,3Δ symmetries are presented. Adiabatic results are also reported for 2Σ, 2Π, and 2Δ electronic states of the molecular ion LiNa+ dissociating into Li (2s, 2p, 3s, and 3p) + Na+ and Li+ + Na(3s, 3p, 4s, 3d, and 4p). We use an ab initio approach involving a non-empirical pseudopotential for the Li (1s2) and Na (1s22s22p6) cores and core valence correlation correction. A very good agreement is obtained for some lowest states of the LiNa and
LiNa+ molecules for spectroscopic constants with the available theoretical works. The existence of numerous avoided crossings between
electronic states of 2Σ and 2Π symmetries is related to the charge transfer process between the two ionic systems Li+Na and LiNa+. 相似文献
1000.
采用双水电极介质阻挡放电装置,在氩气/空气混合气体放电中,在三种边界条件下得到了一种新型的超六边形斑图.给出了超六边形斑图的傅里叶变换及其不同模强度随旋转角的变化.实验测量了超六边形斑图随空气含量和外加电压变化的相图.研究了超六边形斑图的时空动力学,发现超六边形斑图是由两套子结构嵌套而成.在四边形边界条件下,研究了放电面积的大小对斑图模式选择的影响.发现超四边形斑图的形成受边界条件影响很大,而超六边形斑图则是自组织的结果.
关键词:
介质阻挡放电
超六边形斑图
时空动力学
边界条件 相似文献