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91.
The equation of state of symmetric nuclear matter is calculated using the relativistic Hamiltonian (HR) with potentials which have been fitted with the N -N scattering data using the relativistic two-body Hamiltonian ( [(v)\tilde]14 \tilde{{v}}_{{14}}^{} and the non-relativistic two-body Hamiltonian, i.e. the Argonne V14 interaction. The boost interaction corrections as well as the relativistic one-body and two-body kinetic energy corrections
in cluster expansion energy within the lowest-order-constrained variational method are calculated. It is shown that the relativistic
corrections reduce the binding energy by 1.5MeV for [(v)\tilde]14 \tilde{{v}}_{{14}}^{} and AV14 interactions. The symmetric nuclear-matter saturation energy is about -16.43 MeV at r \rho = 0.253 (fm-3) with [(v)\tilde]14 \tilde{{v}}_{{14}}^{} interaction plus relativistic corrections. Finally, various properties of the symmetric nuclear matter are given and a comparison
is made with the other many-body calculations. 相似文献
92.
The properties of asymmetric nuclear matter for a wide range of densities and asymmetric parameters are investigated within
the lowest-order-constrained variational (LOCV) method by employing the relativistic Hamiltonian with a potential which has
been fitted relativistically to N-N phase shifts ( [(v)\tilde]14 \tilde{{v}}_{{14}}^{} and to the AV14interaction. Like our previous work on symmetric nuclear matter, the boost interaction corrections as well as the relativistic
one-body and two-body kinetic corrections are calculated. The various properties of asymmetric nuclear matter such as the
symmetry energy, the saturation energy and the validity of the a2 \alpha^{2}_{} law, etc., are examined. The symmetry energy is reduced by about 7MeV when we use [(v)\tilde]14 \tilde{{v}}_{{14}}^{} instead of its non-relativistic version, i.e. the AV14interaction. The results are compared with other many-body calculations. 相似文献
93.
The problem of forced convection in a channel filled with a nanofluidsaturated porous medium is investigated, numerically. A finite difference Computational Fluid Dynamics (CFD) model with structured uniform grid system is employed to solve the momentum and energy equations. In modeling flow in the channel, the effects of flow inertia, variable porosity and Brinkman friction are taken into account. Studies are carried out for different nanoparticles with different volume fractions in the range 0%-4% and different nanoparticle diameters. Comparison made between our numerical and semi analytical Differential Transform Method (DTM) results with those in previous published research is found to be appropriate. Results show that increasing either nanoparticls volume fraction or pressure gradient parameter improves heat transfer. Further, for large quantities of nanoparticle concentration and pressure gradient, the channeling phenomenon is intensified. 相似文献
94.
95.
Saeed Dinarvand Ahmad Doosthoseini Ensiyeh Doosthoseini Mohammad Mehdi Rashidi 《Nonlinear Analysis: Real World Applications》2010,11(2):1159-1169
The similarity solution for the unsteady laminar incompressible boundary layer flow of a viscous electrically conducting fluid in stagnation point region of an impulsively rotating and translating sphere with a magnetic field and a buoyancy force gives a system of non-linear partial differential equations. These non-linear differential equations are analytically solved by applying a newly developed method, namely the homotopy analysis method (HAM). The analytic solutions of the system of non-linear differential equations are constructed in the series form. The convergence of the obtained series solutions is carefully analyzed. Graphical results are presented to investigate the influence of the magnetic parameter, buoyancy parameter and rotation parameter on the surface shear stresses and surface heat transfer. It is noted that the behavior of the HAM solution for the surface shear stresses and surface heat transfer is in good agreement with the numerical solution given in reference [H. S. Takhar, A. J. Chamkha, G. Nath, Unsteady laminar MHD flow and heat transfer in the stagnation region of an impulsively spinning and translating sphere in the presence of buoyancy forces, Heat Mass Transfer 37 (2001) 397]. 相似文献
96.
The paper deals with a problem motivated by survivability issues in multilayer IP-over-WDM telecommunication networks. Given a set of traffic demands for which we know a survivable routing in the IP layer, our purpose is to look for the corresponding survivable topology in the WDM layer. The problem amounts to Multiple Steiner TSPs with order constraints. We propose an integer linear programming formulation for the problem and investigate the associated polytope. We also present new valid inequalities and discuss their facial aspect. Based on this, we devise a Branch-and-cut algorithm and present preliminary computational results. 相似文献
97.
Sanati Hassan Karamshahi Zahra Ghorbani-Vaghei Ramin 《Research on Chemical Intermediates》2019,45(2):709-726
Research on Chemical Intermediates - This work describes a new method for a one-pot multicomponent condensation of a variety of aldehydes with dimedone and malononitrile in water, providing a... 相似文献
98.
The anomalous behavior of a polychromatic beam reflected from the interface of two homogeneous dielectric media at the neighborhood of Brewster's angle is investigated theoretically and examined experimentally. An explicit expression is derived for the spectrum at an arbitrary observation point for a given incident spectrum. By introducing a modifier function it is shown that the spectrum at each point sensitively depends on the observation angle just in the immediate neighborhood of Brewster's angle and wavelength. Finally, the obtained results are applied to account for the horizontal parts of the supernumerary rainbows. 相似文献
99.
100.
Zeinab Ahmadvand Mehdi Bayat Mohammad Ali Zolfigol 《Journal of computational chemistry》2020,41(26):C1-C1
Pd-PEPPSI type complexes are widely used as precatalyst in a variety of organic reactions, including the Negishi, Kumada and Suzuki-Miyaura cross-coupling reactions. The aim of this research is to determine potential proposed reaction pathways 1, 2, or 2′ (See Schemes 1 and S1–S4 ) for Pd-PEPPSI precatalyst activation in the presence of ethylene glycol as a solvent also in the gas phase at Cam-B3LYP-D3 method nominated among eight DFT methods examined. There is also investigation into the impact of promoter bases (NaOEt, NaOiPr, NaOtBu) on precatalyst activation of Pd-PEPPSI. Eventually, the most favorable proposed reaction pathway and promoter base for reducing Pd(II) to Pd(0) are predicted computationally. Notably, our findings are consistent with the organ Pd-PEPPSI type complexes that offer increased catalytic activity and provide basic information in the presence of solvents designing the monoligated Pd(0)-solvent. 相似文献