MRC, Université Libre de Bruxelles, 50, Av. F.D. Roosevelt-CP-165/62, B-1050, Brussels, Belgium.
J Chem Phys. 2012 Jun 28;136(24):244512. doi: 10.1063/1.4730306.
We report on the measurement of diffusion (D), thermodiffusion (D(T)), and Soret (S(T)) coefficients in water-isopropanol mixtures by three different instrumental techniques: thermogravitational column in combination with sliding symmetric tubes, optical beam deflection, and optical digital interferometry. All the coefficients have been measured over the full concentration range. Results from different instruments are in excellent agreement over a broad overlapping composition (water mass fraction) range 0.2 < c < 0.7, providing new reliable benchmark data. Comparison with microgravity measurements (SODI/IVIDIL (Selected Optical Diagnostic Instrument/Influence of VIbration on DIffusion in Liquids)) onboard the International Space Station and with literature data (where available) generally gives a good agreement. Contrary to theoretical predictions and previous experimental expectations we have not observed a second sign change of S(T) at low water concentrations.
热重力柱结合滑动对称管、光偏转和光数字干涉法，测量水-异丙醇混合物中的扩散（D）、热扩散（D(T)）和 Soret（S(T)）系数。所有系数都在全浓度范围内进行了测量。不同仪器的结果在广泛重叠的组成（水质量分数）范围内 0.2 < c < 0.7 非常吻合，提供了新的可靠基准数据。与国际空间站上的微重力测量（SODI/IVIDIL（选择光学诊断仪器/振动对液体扩散的影响））和文献数据（在可用的情况下）的比较通常是一致的。与理论预测和以前的实验预期相反，我们没有观察到在低水浓度下 S(T)的第二个符号变化。
