We present a comprehensive study of vortex matter in the FeSe1−x S x system with various doping degree. The influence of sulphur substitution on peak effect occurrence is studied. Additionally, we study a possible vortex liquid–vortex glass/lattice transition and find an evidence that the vortex liquid–vortex glass phase transition in FeSe1−x S x has a quasi two–dimensional nature. We investigate the upper critical field behaviour in FeSe1−x S x system, and found that the upper critical field is higher than that predicted by the Werthamer–Helfand–Hohenberg (WHH) model, whereas its temperature dependence could be fitted within a two-band framework. Finally, a detailed H–T phase diagram is presented.

The data of studies on the effectiveness of impregnating Aquastat waste generated as a result of the development of limestone-shell rock deposits are presented. As a result of sand impregnation, the water absorption coefficient as a result underwent a significant decrease from 7 to 17 times, while the water absorption coefficient decreases from 32.5% for the initial to 1.9% impregnated. Even treatment with low concentrated (ρ = 1.17 g / cm 3) calcium polysulfide solution made the water absorption coefficient to decrease to a value of 4.5%. As a result of impregnation of crushed stone from limestone-limestone with a solution of calcium polysulfide, the water absorption coefficient decreases from 25.0% for untreated to 5.2% for treated, and the decrease in the coefficient of water absorption is greater for concentrated solutions. It was found that a solution density of 1.24 g/cm 3 is sufficient to reduce the water absorption coefficient to a value of 5.2%, the same as for a density value of 1.35 g/cm 3. Comparison of the results of impregnation with «Aquastat» solution and sulfur melt showed that as a result of treatment with sulfur melt, the water absorption coefficient decreases by 13.3 and strength increases by 2 times, and as a result of impregnation with «Aquastat» solution decreases by 4.62%, strength increases by 1.35 times. Despite the high efficiency of sulfur melt processing, such treatment has drawbacks associated with the use of autoclave technology and high temperatures. The results of the modification of sand and crushed stone from shell rock by impregnating it with the «Aquastat» solution, a significant decrease in the water absorption parameter, an increase in compressive strength, revealed the possibility of using impregnated crushed stone as the layer material lying at the base of the road structures of local roads in the form of crushed stone and sand instead of the more expensive imported crushed stone.

ExtEndEd AbstrAct:The data of studies on the effectiveness of impregnation with polysulfide solutions of shell limestone used as facing and wall material, as well as for the manufacture of road products are presented. Modification of the limestone with the impregnating composition «Akvastat» created by the authors which is sulfur-containing water-based solution of calcium polysulfide containing alcohols and surfactants, can significantly reduce water absorption and increase durability of limestone.Impregnating composition on the basis of calcium polysulfide possesses density of 1.22-1.24 g/cm 3 , the infiltrant penetrates into the pore structure of limestone to a depth of 4 cm or more, depending on the density and structure of the sample. While the material is drying, sulfur nanoparticles are crystallized from the polysulfide solution in its pores. They partially fill pore space and form protective durable insoluble hydrophobic coating that impedes the penetration of

The problem of creating reliable protective coatings that increase the mechanical characteristics of concrete building structures (piles, bridges, ceiling arches, tunnels, chutes, culverts, wells, paving slabs and curbs, etc.) operated under the influence of atmospheric factors and groundwater is of great importance. Currently, the most effective way to prevent degradation of materials is the application of various kinds of protective compounds. That protects against various factors of aggressive natural and manmade impact and thus allows increasing the durability of buildings and structures by reducing the amount of water penetrating into the pores. To provide long-term protection of building materials, it is proposed to treat porous surfaces of building materials with a new sulfur-containing compound. The innovative developed impregnating composition is based on sulfur and it provides protection of building materials of different nature from weathering and corrosive media for a long time. Modification of the proposed composition can significantly improve performance and increase the service life of building materials.

ExtEndEd AbstrAct:The results of research on hydrophobic impregnation of dense concrete with composition «Aquastat» designed for manufacture of road and airfield plates are presented. It was found that after having been treated with waterrepellent agent the concrete sample is resistant to wetting, i.e. it gets hydrophobic properties. At the same time the water absorption of the samples treated for 24 hours at atmospheric pressure is reduced in three times, and soaked for 0.5 hours under vacuum decreases 5.5 times. It was revealed that the hydrophobic properties of fine-grained concrete impregnated with «Aquastat» may be at