The Taylor dispersion method was used to measure diffusion coefficients of three-component liquid systems. An improved constrained nonlinear least-square method was used to evaluate the ternary diffusion coefficients ...The Taylor dispersion method was used to measure diffusion coefficients of three-component liquid systems. An improved constrained nonlinear least-square method was used to evaluate the ternary diffusion coefficients directly by fitting the mathematical solutions of the dispersion equation to eluted solute peaks detected using a differential refractometer. Diffusion coefficients of the three-component system of acetone-benzene-CCl4, determined at 25℃, were used to test the procedure. The measured diffusion coefficients were compared with values obtained by optical interferometry and the diaphragm cell method. Ternary diffusion coefficients are also determinated for solutions of 1-hexanol-hexane-toluene and 1-propanol- water-ethylene glycol at 25℃, with an accuracy of approximately 0.05 m^2·s^- 1.展开更多
研究了一类具非线性扩散系数和阻尼项的双曲型偏微分方程系统2ui(x,t)/t2+m(t)ui(x,t)/t=ai(t)hi(ui)Δui+sum from j=1 to n aij(t)hij(ui(x,t-τj(t)))Δui(x,t-τj(t))-sum from k=1 to m bik(x,t)uk(x,t-σ(t))(x,t)∈Ω...研究了一类具非线性扩散系数和阻尼项的双曲型偏微分方程系统2ui(x,t)/t2+m(t)ui(x,t)/t=ai(t)hi(ui)Δui+sum from j=1 to n aij(t)hij(ui(x,t-τj(t)))Δui(x,t-τj(t))-sum from k=1 to m bik(x,t)uk(x,t-σ(t))(x,t)∈Ω×R+≡G,i=1,2,…m,获得了该方程组在Robin边值条件下解振动的充分条件。展开更多
基金Supported by the National Natural Science Foundation of China (No. 29836130) and the German Research Foundation of Germany
文摘The Taylor dispersion method was used to measure diffusion coefficients of three-component liquid systems. An improved constrained nonlinear least-square method was used to evaluate the ternary diffusion coefficients directly by fitting the mathematical solutions of the dispersion equation to eluted solute peaks detected using a differential refractometer. Diffusion coefficients of the three-component system of acetone-benzene-CCl4, determined at 25℃, were used to test the procedure. The measured diffusion coefficients were compared with values obtained by optical interferometry and the diaphragm cell method. Ternary diffusion coefficients are also determinated for solutions of 1-hexanol-hexane-toluene and 1-propanol- water-ethylene glycol at 25℃, with an accuracy of approximately 0.05 m^2·s^- 1.
文摘研究了一类具非线性扩散系数和阻尼项的双曲型偏微分方程系统2ui(x,t)/t2+m(t)ui(x,t)/t=ai(t)hi(ui)Δui+sum from j=1 to n aij(t)hij(ui(x,t-τj(t)))Δui(x,t-τj(t))-sum from k=1 to m bik(x,t)uk(x,t-σ(t))(x,t)∈Ω×R+≡G,i=1,2,…m,获得了该方程组在Robin边值条件下解振动的充分条件。
