Diffusion in the Micro-Channel Flow Driven by Electroosmosis
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摘要: 利用差分方法对电渗驱动微通道中的脉冲样品的浓度扩散进行了数值模拟，结果说明外加电场和缓冲液浓度对样品的扩散起着重要的作用，而水力直径及其通道的高宽比对扩散的影响甚微．采用减小外加电场和减小缓冲液浓度的办法，可以防止样品带宽的增大、增强检测和分离的效果，同时又保持比较快的输送速度．该结论对于微通道的优化设计具有参考价值．Abstract: Numerical simulation using the finite differential method was carried out to analyze the diffusion of an impulse sample in the micro-channel driven by electroosmosis. The results show that the electrical field strength applied externally and the concentration of buffer solution played a significant role in the diffusion of sample, however, hydraulic diameter and aspect ratio of height to width of channel played a small role in it. Weakening the electrical field strength applied externally and the concentration of buffer solution properly could prevent the sample band from broadening effectively, and promoted the efficiency of testing and separation as well as kept a faster speed of transport. The conclusions were helpful to the optimal design for micro-channel.
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Key words:
- micro-channel /
- diffusion /
- driven by electroosmosis /
- numerical simulation
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