第3章表面张力及表面活性剂在界面上的吸附.pptVIP

第三章表面张力及表面活性剂在界面上的吸附;表面现象;Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.;表面现象;3.1表面张力与表面自由能;3.1.1表面张力?(Surface Tension);;Surface tension of water drop;3.1.1表面张力?(Surface Tension);3.1.2 surface free energy;表面自由能(Surface Free Energy);表面自由能(Surface Free Energy);表面自由能(Surface Free Energy);表面自由能(Surface Free Energy);表面自由能与表面张力;表面自由能与表面张力;若以表面自由能的单位：J/m2来表示，其数值应该为多少？;Table 3.1: Surface tensions γ of some liquids at different temperatures T.;表面张力的微观成因;思考题;3.2弯曲液面下的附加压力Curved liquid surfaces with additional pressure;3.2弯曲液面下的附加压力;From a comparison of similar triangles, it follows that ;If the surface is to be in mechanical equilibrium, the two work terms as given must be equal, and on equating them and substituting in the expressions for dx and dy, the final result obtained is ;Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.;Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.;f;Example 2.4. How large is the pressure in a spherical bubble with a diameter of 2 mm and a bubble of 20 nm diameter in pure water, compared with the pressure outside? For a bubble the curvature is identical to that of a sphere: R1 = R2 = R. ;Therefore ΔP =2γ/R (2.6) With R = 1 mm we get ΔP = 0.072J/m2 ×2/10?3m= 144 Pa With R = 10 nm the pressure is ΔP = 0.072 J/m2 × 2/10?8m = 1.44 × 107 Pa =144 bar. ;毛细现象;弯曲液面的力平衡条件;弯曲液面的力平衡条件;3.3Techniques to measure the surface tension;;Maximum-bubble-pressure method;表面张力测定装置 ;Drop-weight method;Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.;ring tensiometer, called also the Du-Noüy tensiometer;theWilhelmy plate method;吊片法;脱环法(环法);滴体积法：;停滴法和悬滴法：;3.4.1表面过剩和吉布斯等温吸附式(surface excess and Gibbs adsorption isotherm);Effects of simple electrolytes on the surface tension of water: (a) LiCl; (b) NaC