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201.
The observability of a charged Higgs boson produced in association with a W boson at future muon colliders is studied. The analysis is performed within the MSSM framework. The charged Higgs is assumed to decay to $t\bar{b}We study $B_{s}^{0} \to J/\psi f_{0}(980)$ decays, the quark content of f 0(980) and the mixing angle of f 0(980) and ??(600). We calculate not only the factorizable contribution in the QCD factorization scheme but also the nonfactorizable hard spectator corrections in QCDF and pQCD approach. We get a result consistent with the experimental data of $B_{s}^{0} \to J/\psi f_{0}(980)$ and predict the branching ratio of $B_{s}^{0}$ ?CJ/???. We suggest two ways to determine f 0?C?? mixing angle ??. Using the experimental measured branching ratio of $B_{s}^{0} \to J/\psi f_{0}(980)$ , we can get the f 0?C?? mixing angle ?? with some theoretical uncertainties. We suggest another way to determine the f 0?C?? mixing angle ?? using both experimental measured decay branching ratios $B_{s}^{0} \to J/\psi f_{0}(980) (\sigma)$ to avoid theoretical uncertainties.  相似文献   
202.
203.
The place of fuzzy concepts in traffic assignment (TA) models has been studied in recent literature. Keeping fuzzy level of travel demand in mind, we propose a new TA model in which the travel costs of links are depended on their congestion. From the results of such fuzzy TA model, network planners are able to estimate the number of travelers on network links. By using zero–one variables, the proposed model is transformed into a crisp mixed-integer problem with respect to path-flow variables. In order to produce the Logit flows from this problem, Damberg et al. algorithm is modified. Then, the level of certainty is maximized and perceived travel delays are minimized. For a fixed certainty degree, the obtained solution, which is named the fuzzy equilibrium flow, satisfies a quasi-Logit formula similar to ordinary expression of the Logit route choice model. Eventually, we examine the quality of different path enumeration techniques in the proposed model.  相似文献   
204.
Journal of Thermal Analysis and Calorimetry - The paper presents the mixed convection heat transfer and entropy generation of a nanofluid containing carbon nanotubes, flowing in a 3D rectangular...  相似文献   
205.
Research on Chemical Intermediates - Using the heterometallic oxo-centered trinuclear [ZnFe2O(CH3COO)6(H2O)3]·2H2O complex as a novel precursor, pure and single-phase ZnFe2O4 nanostructure was...  相似文献   
206.
Molybdenum disulfide nanoflakes (MoS2) are superior material for their semiconducting properties. For bulk and monolayer MoS2 the band gap changes from indirect-to-direct, respectively. So, it exhibits promising prospects in the applications of optoelectronics and valleytronics, such as solar cells, transistors, photodetectors, etc. In this research, the influence of different Ar flow rates as the carrier gas, is investigated for growing MoS2 nanoflakes on silicon substrates using one-step thermal chemical vapor deposition by simultaneously evaporating of solid sources like sulfur and molybdenum trioxide powders. The structural and optical properties of the obtained nanoflakes are assessed by using X-ray diffraction pattern, scanning electron microscopy, UV–visible absorption, photoluminescence and Raman spectroscopy. It is shown that, Ar gas flow rate is strongly affects on the final products as few-layer MoS2 structures. Moreover, the abundance of MoS2 in comparison to MoO2 and MoO3 structures, in the obtained nanoflakes, is influenced by the Ar flow rate.  相似文献   
207.
Richards’ equation is a nonlinear partial differential equation governing unsteady seepage flow through unsaturated porous media. This paper investigates applicability of radial basis function-based differential quadrature (RBF-DQ), as a meshless method, to simulate one-dimensional flow processes in the unsaturated zone under different initial and boundary conditions. Fourth-order Runge–Kutta scheme has been adopted for time integration. Results of solving three numerical examples using RBF-DQ are compared with those of analytical, numerical, and experimental solutions presented in the literature. The comparison indicates that RBF-DQ can provide more accurate results comparing with traditional FDM or FEM without the need to discretize the computational domain. Moreover, the merit of mesh-free characteristic in RBF-DQ makes it suitable not only for solving nonlinear problems but also for dealing with multidimensional problems since meshless methods are not restricted to dimensional limitations. A key parameter in utilizing multiquadratic approximation in RBF-DQ method is the user-defined shape parameter C, which may significantly affect solution accuracy. Thus, a sensitivity analysis has been conducted to study possible effects of shape parameter on achieved results.  相似文献   
208.
Using first-principles approach, we theoretically study the effect of anion/cation vacancies on structural and electro-magnetic properties of zigzag AlN nanoribbons (ZAlNNRs). Calculations were performed using a full spin-polarized method within the density functional theory (DFT). Our findings shed light on how the edge states combined with vacancy engineering can affect electro-magnetic properties of ZAlNNRs. We found that depending on the nature and number of vacancies, ZAlNNRs can design as half-metal or semiconductor. Our results reveal a significant amount of spin magnetic moment for ZAlNNR with Al vacancies (VAl). These results may open new applications of AlN nano-materials in spintronics.  相似文献   
209.
Akgül  Ali  Inc  Mustafa  Hashemi  Mir Sajjad 《Nonlinear dynamics》2017,88(4):2817-2829

This paper introduces that the nonlinear Poisson–Boltzmann equation for semiconductor devices describing potential distribution in a double-gate metal oxide semiconductor field effect transistor (DG-MOSFET) is exactly solvable. The DG-MOSFET shows one of the most advanced device structures in semiconductor technology and is a primary focus of modeling efforts in the semiconductor industry. Lie symmetry properties of this model is investigated in order to extract some exact solutions. The reproducing kernel Hilbert space method and group preserving scheme also have been applied to the nonlinear equation. Numerical results show that the present methods are very effective.

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210.
In this letter,the Lie point symmetries of the time fractional Fisher(TFF) equation have been derived using a systematic investigation.Using the obtained Lie point symmetries,TFF equation has been transformed into a different nonlinear fractional ordinary differential equations with the Erd′elyi–Kober fractional derivative which depends on the parameter α.After that some invariant solutions of underlying equation are reported.  相似文献   
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