Micellisation of Binary Mixtures of Surfactants Na-Deoxycholate–Na-Decyl Sulfate and Na-Hyodeoxycholate–Na-Decyl Sulfate in Water Solutions: Rational Development of the Thermodynamic Model for the Excess Gibbs Energy (GE)

2018 ◽  
Vol 63 (3) ◽  
pp. 691-701 ◽  
Author(s):  
Mihalj Poša ◽  
Ana Pilipović ◽  
Vesna Tepavčević ◽  
Stoja Obradović
1991 ◽  
Vol 69 (12) ◽  
pp. 2117-2121 ◽  
Author(s):  
T. S. Banipal ◽  
B. S. Lark ◽  
S. Singh

Total vapour pressures for binary mixtures containing acetic acid, propionic acid, isobutyric acid, and trimethylacetic acid with acetonitrile have been measured for the entire composition range at 298.15 and 318.15 K using a static manometric method. All systems show positive deviations from Raoult's law, enhanced by both an increase in temperature and an increase in the methylation of acetic acid. Activity coefficients have been calculated by taking into consideration the dimerization of these carboxylic acids in the vapour phase. TSE values obtained from GE and earlier reported HE values are found to be negative for acetic acid, about zero for propionic and isobutyric acids, and positive for trimethylacetic acid for the whole composition range. The results have been interpreted in terms of various contributions such as depolymerization, heteromolecular dipole–dipole interactions, and the increasing dimerization constant and steric hindrance with increase of complexity of the acid. Key words: excess Gibbs energy, carboxylic acids, acetonitrile, activity coefficients


1996 ◽  
Vol 126 (1) ◽  
pp. 127-134 ◽  
Author(s):  
Mariana Teodorescu ◽  
Alexandru Barhala ◽  
Dumitru I. Marchidan ◽  
Ortansa Landauer

2005 ◽  
Vol 475-479 ◽  
pp. 3327-3330 ◽  
Author(s):  
Sang Hwan Lee ◽  
Kyung Sub Lee ◽  
Kyung Jong Lee

The dilute solution model is quite widely used because the chemical potential is more easily defined than that in the sub-lattice model. In the present study, the thermodynamic model for the Fe-Mn-Si-Nb-Ti-V-C system was conducted by evaluating Wagner interaction parameters. The data used in this work was collected and modified by means of TCFE 2000-database in Thermo-Calc and up-to date references. The relationship of interaction parameters(L) in the sub-lattice model and Wagner interaction parameters in the dilute solution model was derived. The composition dependency of reference state and the higher order interaction parameters of the excess Gibbs energy were considered to evaluate Wagner interaction parameters. The equilibrium compositions of austenite and fractions of phases and the dissolution temperature of precipitates(NbC, VC, and TiC) were evaluated by the dilute solution model and compared with the results by the sub-lattice model.


2005 ◽  
Vol 70 (1) ◽  
pp. 9-20 ◽  
Author(s):  
Dragan Manasijevic ◽  
Dragana Zivkovic ◽  
Katayama Iwao ◽  
Zivan Zivkovic

The results of the calculation of the thermodynamic properties for liquid Ga-Sb-Tl alloys at the temperature 1073 K are presented in this paper. Initially, the most appropriate thermodynamic model for the investigated system was selected. Based on a comparison of the values calculated by different geometric models (Kohler, Muggianu, Toop, Hillert, Chou) with the existing experimental based data, asymmetric models of calculation were determined to give the best results. The asymmetric nature of the investigated ternary system was additionally confirmed by the Chou similarity coefficient concept. For these reasons, further complete thermodynamic calculations were performed according to the Hillert model in five sections of the ternary Ga-Sb-Tl system from each corner with the mole ratio of other two components being 9:1; 7:3; 5:5; 3:7 and 1:9. The obtained results include integral excess Gibbs energy dependences on composition for all the investigated sections. The calculated activity values at 1073 K for all components are given in the form of isoactivity diagrams. Comparison between the calculated and experimentally obtained gallium activities shows good agreement.


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