A kind of electric circuit is improved to optimize the linearity of edge filter demodulators in FBG .By using a logarithm amplifier and an extraction operation, the linear range of optimized edge filter demodulators h...A kind of electric circuit is improved to optimize the linearity of edge filter demodulators in FBG .By using a logarithm amplifier and an extraction operation, the linear range of optimized edge filter demodulators has been broadened effectively, and the requirement of optical filter's linear range has been reduced. Theoretical analyses and the simulation results indi-cated that the linear range of optimized edge fdter demodulator's covers the whole transition region of the edge filter, while a strict linearity of the optical filter is not necessary.展开更多
The bilinear form of the (2+1)-dimensional non-isospectral AKNS system is derived. Its N-soliton solutions are obtained by using the Hirota method. As a reduction, a (2+1)-dimensional non-isospectral Schrodinger...The bilinear form of the (2+1)-dimensional non-isospectral AKNS system is derived. Its N-soliton solutions are obtained by using the Hirota method. As a reduction, a (2+1)-dimensional non-isospectral Schrodinger equation and its N-soliton solutions are constructed.展开更多
In this paper, the pseudo-spectral approximations for a class of the Kdv-Burgers type equation is presented. Convergence and stability of the approximation have been proved by Sobolev's inequalities and the bounde...In this paper, the pseudo-spectral approximations for a class of the Kdv-Burgers type equation is presented. Convergence and stability of the approximation have been proved by Sobolev's inequalities and the bounded extensive method of the nonlinear function. Finally, the numerical examples are proposed.展开更多
The decomposition method was successfully used in solving of 3D problems with complex geometry shape in electron optics for the FDM (Finite Difference Method) and FEM (Finite Element Method) mostly to implement fa...The decomposition method was successfully used in solving of 3D problems with complex geometry shape in electron optics for the FDM (Finite Difference Method) and FEM (Finite Element Method) mostly to implement fast and robust parallel algorithms and computer codes. We suggest a new version of similar approach for the BEM (Boundary Element Method) based on the alternating method by Schwartz. This approach substantially reduce the dimension of dense global matrix of algebraic system produced by BEM algorithm to solve a complex problem on as single CPU (Central Processor Unit) desktop computer. New algorithm is iterative one, but exponential convergence for the Schwatlz's algorithm creates the fast numerical procedures. We describe the results of numerical simulation for a multi electrode ion transport system. The algorithms were implemented in the computer code "POISSON-3".展开更多
Photolysis rate (J1) and reaction rate constants (kl) for the biacetyl (butane-2,3-dione) were evaluated in aqueous phase using a continuous photolysis system with a conventional Xe-Hg arc lamp as a light source...Photolysis rate (J1) and reaction rate constants (kl) for the biacetyl (butane-2,3-dione) were evaluated in aqueous phase using a continuous photolysis system with a conventional Xe-Hg arc lamp as a light source. The OH radicals was generated by H2OE/UV process and biacetyl (CH3C(O)C(O)CH3) concentrations were monitored using 2,4-DNPH derivatization method. 2,3-butanedione molecule is widely present in the atmosphere, it have been detected in hydrometeors (fogs, rain, and clouds) and at a significant yield (up to 10μmolar). The measurements were performed at 294 K and with free pH values. Our results lead to the following obtained values: J1= 3×10^-4 S^-1 and k1 = (6.17±0.95)×10^8 M^-1·s^-1.The uncertainty listed above is ±15%.展开更多
A high order finite difference-spectral method is derived for solving space fractional diffusion equations,by combining the second order finite difference method in time and the spectral Galerkin method in space.The s...A high order finite difference-spectral method is derived for solving space fractional diffusion equations,by combining the second order finite difference method in time and the spectral Galerkin method in space.The stability and error estimates of the temporal semidiscrete scheme are rigorously discussed,and the convergence order of the proposed method is proved to be O(τ2+Nα-m)in L2-norm,whereτ,N,αand m are the time step size,polynomial degree,fractional derivative index and regularity of the exact solution,respectively.Numerical experiments are carried out to demonstrate the theoretical analysis.展开更多
In this paper, the authors consider the expansion problem of a wedge of gas into vacuum for the two-dimensional Euler equations in isothermal flow. By the bootstrapping argument, they prove the global existence of the...In this paper, the authors consider the expansion problem of a wedge of gas into vacuum for the two-dimensional Euler equations in isothermal flow. By the bootstrapping argument, they prove the global existence of the smooth solution through the direct method in the case 0 〈 θ 〈 -θ=arctan 1/(√2+√5), where θ is the half angle of the wedge. Furthermore, they get the uniform C^1,1 estimates of the solution to the expansion problem.展开更多
Ion-induced charge-transfer states in conjugated polyelectrolytes were experimentally investigated by Justin M.Hodgkiss and his co-workers [J Am Chem Soc,2009,131(25):8913].In this work,charged and neutral conjugated ...Ion-induced charge-transfer states in conjugated polyelectrolytes were experimentally investigated by Justin M.Hodgkiss and his co-workers [J Am Chem Soc,2009,131(25):8913].In this work,charged and neutral conjugated polyelectrolytes were further studied with quantum chemistry methods.The calculation result shows that the absorption spectra are roughly in visible and ultraviolet light regions,and the two absorption peaks are located in the wavelength span 300-400 nm for charged polyelectrolytes.However,in neutral conjugated polyelectrolytes,the peaks of the absorption spectra showed a blue shift compared with those of the charged polyelectrolytes.Charge transfer (CT) properties of the studied compounds were also investigated with both the three-dimensional real-space analysis method of transition and charge difference densities,and the two-dimensional real-space analysis method of transition density matrices based on the simulated absorption spectra.The calculation results revealed the charge transfer in conjugated polyelectrolytes on the excitation states.展开更多
文摘A kind of electric circuit is improved to optimize the linearity of edge filter demodulators in FBG .By using a logarithm amplifier and an extraction operation, the linear range of optimized edge filter demodulators has been broadened effectively, and the requirement of optical filter's linear range has been reduced. Theoretical analyses and the simulation results indi-cated that the linear range of optimized edge fdter demodulator's covers the whole transition region of the edge filter, while a strict linearity of the optical filter is not necessary.
基金The project supported by National Natural Science Foundation of China under Grant No. 10371070 and the Special Funds for Major Specialities of Shanghai Education Committee
文摘Bilinear form of the nonisospectral AKNS equation is given. The N-soliton solutions are obtained through Hirota's method.
基金supported by China Postdoctoral Science Foundation and National Natural Science Foundation of China under Grant No.10771207
文摘The bilinear form of the (2+1)-dimensional non-isospectral AKNS system is derived. Its N-soliton solutions are obtained by using the Hirota method. As a reduction, a (2+1)-dimensional non-isospectral Schrodinger equation and its N-soliton solutions are constructed.
基金Supported by the Natural Science Foundation of Henan Educational Committee(2003110005)Supported by the Natural Science Foundation of Henan University(XK02069)
文摘In this paper, the pseudo-spectral approximations for a class of the Kdv-Burgers type equation is presented. Convergence and stability of the approximation have been proved by Sobolev's inequalities and the bounded extensive method of the nonlinear function. Finally, the numerical examples are proposed.
文摘The decomposition method was successfully used in solving of 3D problems with complex geometry shape in electron optics for the FDM (Finite Difference Method) and FEM (Finite Element Method) mostly to implement fast and robust parallel algorithms and computer codes. We suggest a new version of similar approach for the BEM (Boundary Element Method) based on the alternating method by Schwartz. This approach substantially reduce the dimension of dense global matrix of algebraic system produced by BEM algorithm to solve a complex problem on as single CPU (Central Processor Unit) desktop computer. New algorithm is iterative one, but exponential convergence for the Schwatlz's algorithm creates the fast numerical procedures. We describe the results of numerical simulation for a multi electrode ion transport system. The algorithms were implemented in the computer code "POISSON-3".
文摘Photolysis rate (J1) and reaction rate constants (kl) for the biacetyl (butane-2,3-dione) were evaluated in aqueous phase using a continuous photolysis system with a conventional Xe-Hg arc lamp as a light source. The OH radicals was generated by H2OE/UV process and biacetyl (CH3C(O)C(O)CH3) concentrations were monitored using 2,4-DNPH derivatization method. 2,3-butanedione molecule is widely present in the atmosphere, it have been detected in hydrometeors (fogs, rain, and clouds) and at a significant yield (up to 10μmolar). The measurements were performed at 294 K and with free pH values. Our results lead to the following obtained values: J1= 3×10^-4 S^-1 and k1 = (6.17±0.95)×10^8 M^-1·s^-1.The uncertainty listed above is ±15%.
基金supported by National Center for Mathematics and Interdisciplinary Sciences,CASNational Natural Science Foundation of China (Grant Nos. 60931002 and 91130019)
文摘A high order finite difference-spectral method is derived for solving space fractional diffusion equations,by combining the second order finite difference method in time and the spectral Galerkin method in space.The stability and error estimates of the temporal semidiscrete scheme are rigorously discussed,and the convergence order of the proposed method is proved to be O(τ2+Nα-m)in L2-norm,whereτ,N,αand m are the time step size,polynomial degree,fractional derivative index and regularity of the exact solution,respectively.Numerical experiments are carried out to demonstrate the theoretical analysis.
基金supported by the National Natural Science Foundation of China(No.11371240)Shanghai Municipal Education Commission of Scientific Research Innovation Project(No.11ZZ84)+1 种基金the Fundamental Research Funds for the Central Universities(No.15CX02074A)the grant of “the First-Class Discipline of Universities in Shanghai”
文摘In this paper, the authors consider the expansion problem of a wedge of gas into vacuum for the two-dimensional Euler equations in isothermal flow. By the bootstrapping argument, they prove the global existence of the smooth solution through the direct method in the case 0 〈 θ 〈 -θ=arctan 1/(√2+√5), where θ is the half angle of the wedge. Furthermore, they get the uniform C^1,1 estimates of the solution to the expansion problem.
基金supported by the National Natural Science Foundation of China (Grant Nos.11074210 and 20703032)the National Basic Research Project of China (Grant No.2009CB930703)
文摘Ion-induced charge-transfer states in conjugated polyelectrolytes were experimentally investigated by Justin M.Hodgkiss and his co-workers [J Am Chem Soc,2009,131(25):8913].In this work,charged and neutral conjugated polyelectrolytes were further studied with quantum chemistry methods.The calculation result shows that the absorption spectra are roughly in visible and ultraviolet light regions,and the two absorption peaks are located in the wavelength span 300-400 nm for charged polyelectrolytes.However,in neutral conjugated polyelectrolytes,the peaks of the absorption spectra showed a blue shift compared with those of the charged polyelectrolytes.Charge transfer (CT) properties of the studied compounds were also investigated with both the three-dimensional real-space analysis method of transition and charge difference densities,and the two-dimensional real-space analysis method of transition density matrices based on the simulated absorption spectra.The calculation results revealed the charge transfer in conjugated polyelectrolytes on the excitation states.