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Wetting of low-energy solid surfaces (polymers, hydrophobized glass) with aqueous solutions of binary mixtures of cationic and nonionic surfactants was investigated at molar fractions of the cationic surfactant of 0.2, 0.5, and 0.8. In a narrow concentration range, the non-additive effect of wetting was observed: wetting of the solid surfaces with solutions of the mixtures is better than that would be expected from the additive behavior of the components. The magnitude of the effect depends on the surface energy of the solid substrate, total surfactant concentration in a mixture, and molar fraction of the cationic component. The wetting effect of surfactant mixtures with respect to low-energy solid surfaces can be predicted using the surface tension isotherms.

1.On the creep curve of specimens, like on the creep curve of aneroid barometers, we can distinguish two stages: nonsteady and steady-state creep.2.Producing a field of residual deformations in the specimens by means of preliminary loading makes it possible to reduce the creep rate at the steady-state stage.3.The greater the residual deformation at the initial loading is, the lower is the creep rate at its steady-state stage.4.With rising test temperature the steady-state creep rate somewhat increases, and when so increases, it decreases.5.Increased creep stress sc with the same initial residual stress so leads to increased steady-state creep rate.

The article is devoted to an option to improve the concept designed for the water supply of fire departments during the suppression of peat fires (for example, Tver region) by adding to it a block of bio-energy activation of drinking water. The article deals with a review of the subject area were carried out in order to justify the relevance of the development and statistics on peat fires in the region for the last 5 years. The authors showed the methods of reagent-free water treatment and their comparative analysis. The article gives a detailed analysis of the theoretical basis for the further improvement of the water supply scheme.