Influence of the nature of inorganic salts and their concentration on the simultaneous adsorption of cationic and anionic surfactants. Mixtures of dodecyltrimethylammonium salts with sodium hexylsulfate in the solutions containing the inorganic salt of ions common with the surfactants

Equilibrium vesicles, those which are the stable form of aggregation and form spontaneously on mixing surfactant with water, have never been demonstrated in single component bilayers and only rarely in lipid or surfactant mixtures. Designing a simple and general method for producing spontaneous and stable vesicles depends on a better understanding of the thermodynamics of aggregation, the interplay of intermolecular forces in surfactants, and an efficient way of doing structural characterization in dynamic systems.

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Depression of freezing temperature of water and water solutions in porous materials

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19892644 ◽

1989 ◽

Vol 54 (10) ◽

pp. 2644-2647 ◽

Cited By ~ 1

Author(s):

Petr Schneider ◽

Jiří Rathouský

Keyword(s):

Water Vapor ◽

Porous Materials ◽

Inorganic Salt ◽

Freezing Point ◽

Freezing Temperature ◽

Inorganic Salts ◽

Freezing Point Depression ◽

Salt Solutions ◽

Water Solutions

In porous materials filled with water or water solutions of inorganic salts, water freezes at lower temperatures than under normal conditions; the reason is the decrease of water vapor tension above the convex meniscus of liquid in pores. The freezing point depression is not very significant in pores with radii from 0.05 μm to 10 μm (about 0.01-2.5 K). Only in smaller pores, especially when filled with inorganic salt solutions, this depression is important.

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Adsorption of cationic and anionic surfactants on natural and synthetic carbonate materials

Journal of Colloid and Interface Science ◽

10.1016/j.jcis.2013.07.006 ◽

2013 ◽

Vol 408 ◽

pp. 164-172 ◽

Cited By ~ 73

Author(s):

Kun Ma ◽

Leyu Cui ◽

Yezi Dong ◽

Tianlong Wang ◽

Chang Da ◽

...

Keyword(s):

Anionic Surfactants ◽

Cationic And Anionic Surfactants ◽

Carbonate Materials ◽

Natural And Synthetic

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Liquid–liquid phase separation in particles containing organics mixed with ammonium sulfate, ammonium bisulfate, ammonium nitrate or sodium chloride

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-11723-2013 ◽

2013 ◽

Vol 13 (23) ◽

pp. 11723-11734 ◽

Cited By ~ 63

Author(s):

Y. You ◽

L. Renbaum-Wolff ◽

A. K. Bertram

Keyword(s):

Phase Separation ◽

Sodium Chloride ◽

Liquid Phase ◽

Relative Humidity ◽

Ammonium Sulfate ◽

Inorganic Salt ◽

Liquid Phase Separation ◽

Inorganic Salts ◽

Organic Species ◽

Liquid Liquid Phase Separation

Abstract. As the relative humidity varies from high to low values in the atmosphere, particles containing organic species and inorganic salts may undergo liquid–liquid phase separation. The majority of the laboratory work on this subject has used ammonium sulfate as the inorganic salt. In the following we studied liquid–liquid phase separation in particles containing organics mixed with the following salts: ammonium sulfate, ammonium bisulfate, ammonium nitrate and sodium chloride. In each experiment one organic was mixed with one inorganic salt and the liquid–liquid phase separation relative humidity (SRH) was determined. Since we studied 23 different organics mixed with four different salts, a total of 92 different particle types were investigated. Out of the 92 types, 49 underwent liquid–liquid phase separation. For all the inorganic salts, liquid–liquid phase separation was never observed when the oxygen-to-carbon elemental ratio (O : C) &geq; 0.8 and was always observed for O : C < 0.5. For 0.5 &leq; O : C < 0.8, the results depended on the salt type. Out of the 23 organic species investigated, the SRH of 20 organics followed the trend: (NH4)2SO4 &geq; NH4HSO4 &geq; NaCl &geq; NH4NO3. This trend is consistent with previous salting out studies and the Hofmeister series. Based on the range of O : C values found in the atmosphere and the current results, liquid–liquid phase separation is likely a frequent occurrence in both marine and non-marine environments.

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