scholarly journals Effects of Crown Ethers on the Critical Micelle Concentration and the Micellar Catalysis of Sodium and Potassium Dodecyl Sulfates in Aqueous Solutions

1981 ◽  
Vol 54 (9) ◽  
pp. 2841-2842 ◽  
Author(s):  
Manabu Sen\={o} ◽  
Tomiyuki Namba ◽  
Hideo Kise
Keyword(s):  
Critical Micelle Concentration ◽  
Aqueous Solutions ◽  
Crown Ethers ◽  
Micellar Catalysis ◽  
Sodium And Potassium

Interplay of Lewis acidity, intramolecular O→Sn interactions and selectivity: organotin-functionalized crown ethers as ditopic hosts for sodium and potassium halides

2018 ◽  
Vol 54 (7) ◽  
pp. 739-742 ◽  
Author(s):  
Alain Charly Tagne Kuate ◽  
Muhammad Moazzam Naseer ◽  
Michael Lutter ◽  
Klaus Jurkschat
Keyword(s):  
Crown Ethers ◽  
Lewis Acidity ◽  
Sodium And Potassium ◽  
Potassium Halides

Not only ditopic complexation, but also selectivity has been realized by increasing the Lewis acidity of tin atom in organotin-functionalized crown ethers.

scholarly journals Complex Uranyl Dichromates Templated by Aza-Crowns

Crystals ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 462 ◽  
Author(s):  
Oleg Siidra ◽  
Evgeny Nazarchuk ◽  
Dmitry Charkin ◽  
Stepan Kalmykov ◽  
Anastasiya Zadoya
Keyword(s):  
Aqueous Solutions ◽  
Crown Ethers ◽  
Room Temperature ◽  
Organic Molecules ◽  
Negative Charge ◽  
Uranyl Compounds ◽  
One Dimensional ◽  
Chain Complexes ◽  
Aza Crown Ethers

Three new uranyl dichromate compounds templated by aza-crown templates were obtained at room temperature by evaporation from aqueous solutions: (H2diaza-18-crown-6)2[(UO2)2(Cr2O7)4(H2O)2](H2O)3 (1), (H4[15]aneN4)[(UO2)2(CrO4)2(Cr2O7)2(H2O)] (H2O)3.5 (2) and (H4Cyclam)(H4[15]aneN4)2[(UO2)6(CrO4)8(Cr2O7)4](H2O)4 (3). The use of aza-crown templates made it possible to isolate unprecedented and complex one-dimensional units in 2 and 3, whereas the structure of 1 is based on simple uranyl-dichromate chains. It is very likely that the presence of relatively large organic molecules of aza-crown ethers does not allow uranyl chromate chain complexes to condense into the units of higher dimensionality (layers or frameworks). In general, the formation of 1, 2, and 3 is in agreement with the general principles elaborated for organically templated uranyl compounds. The negative charge of the [(UO2)(Cr2O7)2(H2O)]2−, [(UO2)2(CrO4)2(Cr2O7)2(H2O)]4− and [(UO2)3(CrO4)4(Cr2O7)2]6− one-dimensional inorganic motifs is compensated by the protonation of all nitrogen atoms in the molecules of aza-crowns.

Preparation and Properties of Amide Surfactants

2012 ◽  
Vol 550-553 ◽  
pp. 99-102
Author(s):  
Bao Cai Xu ◽  
Gui Ju Zhang ◽  
Yun Xia Li ◽  
Lu Cui
Keyword(s):  
Surface Tension ◽  
Critical Micelle Concentration ◽  
Aqueous Solutions ◽  
Surface Activity ◽  
Surface Tensions ◽  
Equilibrium Surface ◽  
Minimum Surface Tension ◽  
Dilute Aqueous Solutions ◽  
Lipophilic Groups ◽  
Long Chain

Amide surfactants have modified structures with lipophilic groups connecting hydrophilic groups through amido bond. The preparation of three families of amide surfactants including long chain N-acyl sarcosinates, amidopropyl dimethyl hydroxypropyl sulfobetaines and lauryl amidopropyl trimethyl ammoniums were discussed. The study of the surface activity of these compounds by measuring the equilibrium surface tensions of their dilute aqueous solutions were described. The minimum surface tension and the critical micelle concentration values of these compounds are given.

Evaluation of changing the structure of aqueous solutions in the near-wall layers with using dielectrometry and resonance method

2015 ◽  
Vol 9 (2) ◽  
pp. 0-0
Author(s):  
Саркисов ◽  
Yu. Sarkisov ◽  
Сидоренко ◽  
G. Sidorenko ◽  
Лаптев ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Aqueous Solutions ◽  
Fluid Layer ◽  
Chloride Concentration ◽  
Resonance Method ◽  
Solution Concentration ◽  
Wall Layer ◽  
Oscillatory Circuit ◽  
Structure Of Aqueous Solutions ◽  
Sodium And Potassium

In this work the authors evaluated changes of the structure of aqueous solutions of chlorides of sodium and potassium in various concentrations in the parietal layer by means of the dielectrometry and resonance method. In experiments at 20 ° C, the concentration of sodium and potassium chloride concentration of 0.01 M to 1 M in thenear-wall layer "glass - water solutions" height of less than 1000 microns observed multiple reduction of capacitance of solutions, and Q of an oscillatory circuit and a multiple increase coefficient KS which allows to evaluate the structure of the solutions. It is shown that the structure of the solutions in the wall layer depends on the solution concentration, the nature of the solute and the material of surface. Methods of dielectrometry and resonance are informative in the interpretation of the processes in the fluid layer at the interface, "solid – aqueous solution".

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