Self-diffusion coefficients of sodium dodecyl sulfate (SDS) were measured in aqueous solutions in the premicellar range of the SDS concentrations 7-34.7 mM and temperatures 30-90 C. Average effective hydrodynamic radii and aggregation numbers of SDS in the premicellar region were determined.At C < CMC at all temperatures, the SDS solution is the solution of monomers. At C > CMC, the increase of temperature leads to decrease in the effective hydrodynamic radii and the average aggregation numbers. At C > > CMC, it is impossible to reach the monomeric state by increasing the temperature.

Aggregation numbers were calculated based on measurements of the self-diffusion coefficients, the effective hydrodynamic radii of micelles and aggregates of oxyethylated alkylphenols in aqueous solutions. On the assumption that the radii of spherical micelles are equal to the lengths of fully extended neonol molecules, the limiting values of aggregation numbers corresponding to spherically shaped neonol micelles were calculated. The concentration and temperature ranges under which spherical micelles of neonols are formed were determined.

Translational diffusion coefficients of ethoxylated isononylphenol molecules C 9 H 19 C 6 H 4 O(C 2 H 4 O) n H in carbon tetrachloride were measured by nuclear magnetic resonance diffusometry. The hydrodynamic radii of the molecules were determined within the framework of the Stokes-Einstein relation. We showed that ethoxylated isononylphenols in carbon tetrachloride do not form micelles, and the dependence of the diffusion coefficients and, accordingly, the hydrodynamic radii of the nonionic surfactants on the number of oxyethylene groups have a kink in the region n = 6-8.

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The paper considers the process of applying pedagogical approaches in education, their integration; provides an example of formation of students' educational and cognitive competencies and their thinking in the process of studying, based on the integration of competence, technological and activity approaches, which allow to increase the level of development and effectiveness of university education.