Tomas Bata University in Zlin, Department of Physics and Materials Engineering, Nad Stranemi 4511, 760 05 Zlin, Czech Republic.
J Chromatogr A. 2009 Dec 25;1216(52):9071-80. doi: 10.1016/j.chroma.2009.06.040. Epub 2009 Jun 18.
The behavior of nanometer or micrometer-sized particles, dispersed in liquid phase and exposed to temperature gradient, is a complex and not yet well understood phenomenon. Thermal field-flow fractionation (TFFF), using conventional-size channels, played an important role in the studies of this phenomenon. In addition to thermal diffusion (thermophoresis) and molecular diffusion or Brownian movement, several secondary effects such as particle-particle and/or particle-wall interactions, chemical equilibria with the components of the carrier liquid, buoyant and lift forces, etc., may contribute to the retention and complicate the understanding of the relations between the thermal diffusion and the characteristics of the retained particles. Microthermal FFF is a new high-performance technique allowing much easier manipulation and control of the operational parameters within an extended range of experimental conditions in comparison with conventional TFFF. Consequently, in combination with various other methods, it is well suited for a detailed investigation of the mentioned effects. In this work, some contradictory published results concerning the thermal diffusion of the colloidal particles, studied by TFFF but also by other methods, are analyzed and compared with our experimental findings.
纳米或微米级颗粒在液相中分散并暴露于温度梯度下的行为是一种复杂且尚未得到很好理解的现象。使用常规尺寸通道的热场流分离（TFFF）在该现象的研究中发挥了重要作用。除了热扩散（热泳）和分子扩散或布朗运动之外，颗粒-颗粒和/或颗粒-壁相互作用、与载体液体成分的化学平衡、浮力和升力等几种次要效应也可能导致保留，并使对热扩散和保留颗粒特征之间关系的理解变得复杂。微热 FFF 是一种新技术，与传统 TFFF 相比，它可以在更广泛的实验条件范围内更轻松地操纵和控制操作参数。因此，它与各种其他方法相结合，非常适合详细研究上述效应。在这项工作中，分析了一些关于胶体颗粒热扩散的有争议的已发表结果，这些结果是通过 TFFF 但也通过其他方法研究的，并与我们的实验结果进行了比较。
