Guizhou Normal University is an institution of higher learning in Guiyang, Guizhou Province of the People's Republic of China.The university was founded in 1941, as National Guiyang Normal College . After the formation of the People's Republic of China, it was renamed Guiyang Normal College. In 1985, it became Guizhou Normal University. The university was accredited with being a provincial key university in Guizhou in 1996. In 2004, the former Guizhou Vocational Institute of Technology merged into the University. Wikipedia.
Shang Y.,Guizhou Normal University
Journal of Computational Physics | Year: 2013
Based on two-grid finite element discretization and a recent subgrid-scale model, a twolevel subgrid stabilized Oseen iterative method for the convection dominated Navier-Stokes equations is proposed and analyzed. This method combines the best algorithmic features of the two-grid discretization and subgrid stabilization methods. It first solves a subgrid stabilized nonlinear Navier-Stokes problem by applying m Oseen iterations on a coarse grid, and then solves a linear problem on a finer grid where the nonlinear convection term is fixed by the coarse grid solution. Stability of the method and error estimates of the discrete solution are analyzed. The algorithmic parameter scalings are also derived. Numerical results on an example with known analytical solution, the lid-driven cavity flow and the backward-facing step flow are given to verify the theoretical predictions and demonstrate the method's promise. © 2012 Elsevier Inc.
Bai Z.-Z.,Guizhou Normal University
Computing (Vienna/New York) | Year: 2010
For the singular, non-Hermitian, and positive semidefinite systems of linear equations, we derive necessary and sufficient conditions for guaranteeing the semi-convergence of the Hermitian and skew-Hermitian splitting (HSS) iteration methods.We then investigate the semi-convergence factor and estimate its upper bound for the HSS iterationmethod. If the semi-convergence condition is satisfied, it is shown that the semi-convergence rate is the same as that of the HSS iteration method applied to a linear system with the coefficient matrix equal to the compression of the original matrix on the range space of its Hermitian part, that is, the matrix obtained from the original matrix by restricting the domain and projecting the range space to the range space of the Hermitian part. In particular, an upper bound is obtained in terms of the largest and the smallest nonzero eigenvalues of the Hermitian part of the coefficient matrix. In addition, applications of the HSS iteration method as a preconditioner for Krylov subspace methods such as GMRES are investigated in detail, and several examples are used to illustrate the theoretical results and examine the numerical effectiveness of the HSS iterationmethod served either as a preconditioner forGMRES or as a solver. © 2010 Springer-Verlag.
Peng J.-J.,Guizhou Normal University |
Peng J.-J.,Wuhan Textile University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2016
We derive the off-shell Noether current and potential in the context of Horndeski theory, which is the most general scalar-tensor theory with a Lagrangian containing derivatives up to second order while yielding at most to second-order equations of motion in four dimensions. Then the formulation of conserved charges is proposed on basis of the off-shell Noether potential and the surface term got from the variation of the Lagrangian. As an application, we calculate the conserved charges of black holes in a scalar-tensor theory with non-minimal coupling between derivatives of the scalar field and the Einstein tensor. © 2015 The Author.
Li L.W.,Guizhou Normal University
Laser Physics Letters | Year: 2016
A new strategy to obtain random lasing from semiconductor CdS nanoparticles is presented. A device is prepared with dye (DCM) solution containing CdS NPs. Good lasing behavior is reached and the multiple light scattering process is responsible for lasing generation. We also manage to show that the lasing modes and output intensity exhibit angular dependence. The result indicates that CdS nanoparticles can be used as ideal microlaser material in future semiconductor laser devices. © 2016 Astro Ltd.
Cong Y.,East China University of Science and Technology |
Tian B.,East China University of Science and Technology |
Zhang J.,East China University of Science and Technology |
Zhang J.,Guizhou Normal University
Applied Catalysis B: Environmental | Year: 2011
The microstructure and properties of nitrogen and lanthanum co-doped nanocrystalline titania photocatalysts have been studied. The catalyst samples were prepared in a homogeneous precipitation-hydrothermal process and characterized by XRD, XPS, UV-DRS and BET analyses. The results indicated that the nitrogen and La3+ doping could inhibit the phase transformation and crystallite growth of TiO2 and enhance the thermal stability of TiO2 structure. In addition, the experiment results showed that the thermal stability of TiO2 increased with the increasing of La3+ doping. The photocatalytic activities of samples for photodegradation of rhodamine B under visible light irradiation using different La3+ doping contents were also studied. There were optimal values of La3+ doping content for the La3+ doped and nitrogen/La3+ co-doped TiO2 corresponding the highest photodegradation percentages. The nitrogen and La3+ co-doped titania could greatly improve the photocatalytic activity in visible light irradiation, whose probable mechanism is a synergistic effect of co-doping. The nitrogen doping could narrow the band gap of titania and enhance the utilization efficiency of visible light, while the La3+ doping could accelerate the separation of photo-generated electrons and holes. Furthermore, the La3+ doping could increase the adsorption of organic pollutants on the surface of photocatalyst. © 2010 Elsevier B.V.