液相互扩散系数测量充注方法的改进

Improvement on the jnjection method of liquid mutual diffusion coefficient measurement

中文关键词: 互扩散系数  光干涉法  自动充注  图像处理

英文关键词: Mutual Diffusion Coefficient  Optical Interferometry  Automatic Injection  Image Processing

中文摘要:

      采用Mach–Zehnder干涉法测量液相互扩散系数有利于对扩散机理进行进一步分析。对于黏度值较小的溶液，人工充注溶液时容易引起扰流，由此会导致浓度场产生混乱，进而使得数据处理发生畸变。本文设计的溶液自动充注装置采用步进电机驱动注射器，能有效改善对溶液充注速度的控制，明显提升实验的成功率和测量精度。此外，本文还引入了带自动捕捉功能的矩形窗函数，将图像处理所需的时间大致由25分钟缩短至5分钟。最后，利用改进的实验系统测量了0.33 mol·L-1的氯化钾水溶液的互扩散系数，所得实验结果与文献值相比具有良好的一致性，二者的相对偏差绝对平均值为0.58%。

英文摘要:

      Using Mach–Zehnder interferometry method to measure the mutual diffusion coefficient can contribute to further analysis for diffusion mechanism. For the solution with a small viscosity value, artificial injection is easy to cause turbulence, resulting in chaos in the concentration field and distortion of data processing. In this work, the automatic injection device using the injector with stepping motor was designed, which can effectively improve the control of the solution filling speed, and obviously improve the success rate and measuring precision of the experiment. In addition, this work introduced the rectangle window func-tion with automatic capture function, which greatly reduces the time required for image processing from about 25 minutes to 5 minutes. Finally, the improved experiment system was used to measure the mutual diffusion coefficient of KCl aqueous solution at a molar concentration of 0.33 mol·L-1, which has good consistency with the literature data with an absolute mean of relative deviation of 0.58%.