Relationship between diffusion, self-diffusion and viscosity
نویسنده
چکیده
We investigate the experimental limits of validity of the Stokes–Einstein equation. There is an important difference between diffusion and self-diffusion. The experimental evidences show, that in the case of selfdiffusion the product Dg/T is constant and the Stokes–Einstein equation is still valid. On the other hand, comparison of existing experimental data, on viscosity g and diffusion coefficients D, of small, fast moving ions shows unambiguously that the product Dg/T depends strongly on temperature T. The temperature dependence of diffusion coefficient declines from that of viscosity. Therefore, the Stokes–Einstein equation is not valid in for fast moving ions. 2009 Elsevier B.V. All rights reserved.
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تاریخ انتشار 2009