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1	Free surface films of binary liquid mixtures Bribesh, Fathi January 2012 (has links) Model-H is used to describe structures found in the phase separation in films of binary liquid mixture that have a surface that is free to deform and also may energetically prefer one of the components. The film rests on a solid smooth substrate that has no preference for any component. On the one hand the study focuses on static aspects by investigating steady states that are characterised by their concentration and film height profiles. A large variety of such states are systematically analysed by numerically constructing bifurcation diagrams in dependence of a number of control parameters. The numerical method used is based on minimising the free energy functional at given constraints within a finite element method for a variable domain shape. The structure of the bifurcation diagrams is related to the symmetry properties of the individual solutions on the various branches. On the other hand the full time dependent model-H is linearised about selected steady states, in particular, the laterally invariant, i.e.\ layered states. The resulting dispersion relations are discussed and related to the corresponding bifurcation points of the steady states. In general, the results do well agree and confirm each other. The described analysis is performed for a number of important cases whose comparison allows us to gain an advanced understanding of the system behaviour: We distinguish the critical and off-critical case that correspond to zero and non-zero mean concentration, respectively. In the critical case the investigation focuses on (i) flat films without surface bias, (ii) flat films with surface bias, (iii) height-modulated films without surface bias, and (iv) height-modulated films with surface bias. Each case is analysed for several mean film heights and (if applicable) energetic bias at the free surface using the lateral domain size as main control parameter. Linear stability analyses of layered films and symmetry considerations are used to understand the structures of the determined bifurcation diagrams. For off-critical mixtures our study is more restricted. There we consider height-modulated films without and with surface bias for several mean film heights and (if applicable) energetic bias employing the mean concentration as main control parameter. 530.4
2	Critical Behavior and Crossover Effects in the Properties of Binary and Ternary Mixtures and Verification of the Dynamic Scaling Conception / Kritisches Verhalten und Crossover Effekte in den Eigenschaften Binärer und Ternärer Gemische sowie Verifizierung des Konzeptes der Dynamischen Skalierung Iwanowski, Ireneusz 07 November 2007 (has links) No description available. 530 Physik RR 000 RRJ 000 RRQ 000 RHH 150 RJT 340 RJT 500 RJT 420 RJT 000 Mathematics and Natural Science kritische Gemische binäre Flüssigkeiten ternäre Flüssigkeiten dynamische Skalierungsfunktion Ultraschallabsorptionsverfahren Spektroskopie dynamische Lichtstreuung Relaxationsrate charakteristische Relaxationsrate kritische Verlangsamung chemische Relaxation critical mixture binary mixture ternary mixture system Bhattacharjee-Ferrell crossover theory dynamic scaling function ultrasonic spectroscopy dynamic light scattering relaxation rate characteristic relaxation rate critical slowing down chemical relaxation surface tension Debye col point plait point 33.69 33.30 33.25 33.05 33.07

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Free surface films of binary liquid mixtures

Critical Behavior and Crossover Effects in the Properties of Binary and Ternary Mixtures and Verification of the Dynamic Scaling Conception / Kritisches Verhalten und Crossover Effekte in den Eigenschaften Binärer und Ternärer Gemische sowie Verifizierung des Konzeptes der Dynamischen Skalierung