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EN
Due to the rapid pace of urbanization, the lead-zinc slags previously located outside the settlement turned out to be within the city of Shymkent and began to pose a serious threat to the environment. Therefore, the purpose of the study was to investigate the impact of lead-zinc slags on the environment of Shymkent. It has been revealed that the fields of ruderal plant species are inversely correlated with the lead content in the soil, for phyto-indication of the state of soils, the most informative indicators are the phytocenotic composition and the projective covering of soils with vegetation. At the same time, the proportion of annual species in the control is 53.5 ± 5.6%; with an increase in the toxic load, their role gradually weakens, reaching from 14496.0 ± 105.1 mg/kg Pb2+ to 5.2 ± 0.4%. It was found that Dodartia orientalis, Centaurea squarrosa Willd., Plantago lancetofolium are hyperaccumulators of lead ions, while electron microscopic images showed that lead ions accumulate in the intercellular space of plants, forming significant conglomerates of 10–75 nm. The negative influence of lead-zinc waste has been established, which leads to the accumulation of lead in the blood of children and, as a consequence, is the cause of various diseases. The maximum lead content in the amount of 103 micrograms / dl was found in the blood of children in the area of the city, located 800–1000 m from the slag storage site. Developing hypochromic anemia in children indicates its toxic origin. It was revealed that 90% of children have such pathologies as biliary dyskinesia, dental caries, small anomalies of heart development.
EN
In this study, the effects of replacing fine aggregate by granulated lead/zinc slag waste (GLZSW) on the thickness of concrete shields against X-ray radiation and on the compressive strength of concrete have been investigated. The fine aggregate was substituted by GLZSW in four percentages: 25%, 50%, 75%, and 100% (by weight). The first aim of the present study was to compare the thicknesses of concretes with GLZSW and control concrete using Lead Equivalent (LE). The second aim was to assess the effects of replacing fine aggregate by GLZSW on the compressive strength of concrete. Results of this study indicated that the compressive strength of mixed concretes increased significantly compared to the control upon replacing fine aggregate by GLZSW; the mixture containing 100% GLZSW had the greatest compressive strength. Further, the inclusion of GLZSW as a substitute for fine aggregate increased the radiation attenuation properties and consequently decreased the thickness of concrete shields in direct proportion to the mixing ratio of GLZSW. The results revealed that concrete mixes containing 100% GLZSW offered the greatest reduction in shield thickness. The study shows that there is a promising future for the use of GLZSW as substitute for fine aggregate in concrete used to shield against X-ray radiation.
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