Turchanin A, Tsekov R, Freyland W
Institute of Physical Chemistry, University of Karlsruhe (TH), D-76128 Karlsruhe, Germany.
Phys Chem Chem Phys. 2005 Dec 21;7(24):4146-9. doi: 10.1039/b510757a. Epub 2005 Oct 6.
Oscillatory wetting instabilities driven by capillary-gravitation forces have been explored very recently in the binary fluid Ga-Pb alloy [A. Turchanin, R. Tsekov and W. Freyland, J. Chem. Phys., 2004, 120, 11 171]. This system is characterized by a complete wetting transition at liquid-liquid coexistence. Due to its metallic nature the bulk and interfacial instabilities are strongly coupled via variation of the respective emissivities. In our previous work we have investigated these phenomena at different cooling cycles and at constant temperature inside the miscibility gap. In this study we present for the first time the observations of the oscillatory wetting instabilities also in heating cycles. The interfacial properties of a Ga0.95Pb0.05 alloy at conditions inside the miscibility gap have been investigated by following the second harmonic generation (SHG) intensity changes. Corresponding model calculations of the Pb-rich wetting film instabilities have been performed taking into account the effect of a temperature variation vertical to the bulk sample. The influence of this temperature variation on the occurrence of the oscillations is discussed.
最近，在二元流体镓 - 铅合金中研究了由毛细重力驱动的振荡润湿不稳定性 [A. 图尔查宁、R. 采科夫和W. 弗雷兰德，《化学物理杂志》，2004年，第120卷，第11171页]。该系统的特征是在液 - 液共存时存在完全润湿转变。由于其金属性质，体相和界面不稳定性通过各自发射率的变化而强烈耦合。在我们之前的工作中，我们研究了在不同冷却循环以及在混溶间隙内的恒温条件下的这些现象。在本研究中，我们首次展示了在加热循环中对振荡润湿不稳定性的观测结果。通过跟踪二次谐波产生（SHG）强度变化，研究了混溶间隙内条件下Ga0.95Pb0.05合金的界面性质。考虑到垂直于体相样品的温度变化的影响，对富铅润湿膜不稳定性进行了相应的模型计算。讨论了这种温度变化对振荡发生的影响。
