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Introduction. In this work, Sr-BDC MOFs were obtained by a simple solvothermal process without the use of elevated pressure. This method is easily scalable and does not require any special equipment. In this work, the crystals obtained from the synthesis were studied by Raman spectroscopy. In addition, the obtained materials were analysed for antibacterial activity against Gram-positive and against Gram-negative bacteria.Aim. During this work, the main objective was to comparatively evaluate the antibacterial properties of Sr-BDC MOFs activated by different methods (and without activation).Materials and methods. In this work we used a solvothermal process using terephthalic acid, strontium nitrate and dimethylformamide. The peculiarity of this method is the absence of autoclaving in the synthesis process. Optical microscopy and Raman spectroscopy were used for characterization. Also, to study the antibacterial properties, a medium diffusion test was performed. The combination of these methods will help to establish the relationship between the method of activation and the biological activity of the resulting materials.Results and discussion. In this work, the chemical structure of Sr-BDC MOFs was studied by Raman spectroscopy. The influence of the activation method on the chemical structure of MOFs was studied. It was found that the characteristic peaks of Raman spectroscopy can be used to confirm the removal of solvent (DMFA) from the crystal structure. In addition, tests on the manifestation of antibacterial activity were carried out for MOFs with different activation method. The MIC and MBC were established for each sample.Conclusion. In the course of the work the effect of the activation method on the chemical structure of Sr-BDC MOFs was shown. We also found that the activation method could affect the biological activity of the obtained MOFs. It was also demonstrated that MOFs exhibit different antibacterial activities depending on the type of bacteria, which can be primarily related to the composition of the cell wall of microorganisms.

Two methods of using permanent NdFeB magnets and their impact on the sorption of radionuclides (Cs, Sr, Co) by clinoptilolite and composite sorbents based on zeolites are discussed. Sorption processes were considered under dynamic conditions with liquid circulation. No changes in sorption processes were observed when magnetic treatment was applied to solutions containing radionuclide ions. The natural zeolite clinoptilolite and synthetic zeolites NaX and NaA were considered at this stage. In the work, clinoptilolite from the Sokirnitske deposit in the Zakarpattia region of Ukraine was used. Ukraine possesses significant deposits of clinoptilolite. When magnets were applied to the sorbent during the sorption process, an increase in cobalt sorption of 10% was observed for clinoptilolite, and strontium sorption increased by 17%. The influence of a magnet on clinoptilolite is due to the presence of iron ions in the composition of clinoptilolite. The iron content ranges from 0.9% to 2.5%. The composition of the composite sorbent included clinoptilolite and synthetic zeolite NaX. No increase in radionuclide sorption was observed for composite sorbents, likely due to the presence of clinoptilolite in the sorbent composition and the corresponding iron content. The analytical part of the study was carried out using the PIXE (Particle Induced X-ray Emission) method on the analytical nuclear-physics complex "Sokil." The energy range of the accelerator was 200-2000 keV. The complex made it possible to carry out all the main methods of analysis using ion beams. The targets were placed in the exit, at the Chamber for PIXE. To excite the atoms of cesium, strontium, and cobalt a proton beam with an energy of Ер≈1400 keV was used.

The decontamination properties of shampoos for cesium, strontium, and cobalt were determined. The method has been developed for determining the decontaminating properties of shampoos. The chemical part of the study includes the preparation of hair, which consists of forced pollution and subsequent washing. Stable isotopes were used in the work. This has increased the safety of staff during chemical hair research. The analytical part includes the quantitative determination of the cesium, strontium, and cobalt in the hair, which was carried out by the Particle-Induced X-ray Emission (PIXE) method using the analytical nuclear-physical complex "Sokol". Various shampoos were analyzed, and their decontamination properties were determined. During the research, various samples of shampoos, which are presented on the market of Ukraine, were considered. It has been established that TM "Ringo" shampoo has the best deactivating properties for cesium (Kd - 574.0) and insignificant deactivating properties for strontium (Kd - 3.1) and cobalt (Kd - 3.6). It was determined that with multi-isotope contamination (a mixture of cesium, strontium, and cobalt isotopes) decrease in the deactivation coefficient for all isotopes was observed, which is due to the competition factor of the isotopes in the complexation process with shampoo. Reduction of decontaminating properties was observed on all samples of shampoos.

In the course of the research, the effect of competing ions (Na+) on multisorption (Cs+, Sr2+) by composite sorbents based on natural and synthetic zeolites under static conditions was studied. It was found that the maximum concentration of competing ions (0.4 g of NaCl per 100 ml of solution) leads to a decrease in cesium sorption by 20%, and strontium sorption decreases by 10%. At the same time, high rates of sorption of cesium and strontium are preserved. Thus, for a composite sorbent (clinoptilolite -30%: zeolite NaX -70%), the sorption of cesium was 67.9%, and the sorption of strontium was 87.6%. The analytical technique was developed on the basis of the PIXE (Proton Induced X-ray Emission) method and made it possible to qualitatively and quantitatively determine the content of isotopes. The work was performed at the analytical nuclear-physical complex "Sokil". The energy range of the electrostatic accelerator is 200-2000 keV. The complex made it possible to carry out all the main methods of analysis using ion beams. The targets were placed in the exit, at the Chamber for PIXE. To carry out measurements, a vacuum with a pressure of 10-4 Pa was created in the chamber. To excite the atoms of cesium, strontium, a proton beam with an energy of Ер≈1400 keV was used. The characteristic X-ray radiation of the L-series of cesium atoms and K-series of strontium atoms was recorded by two detectors: XR-100CR Si-PIN X-Ray and Ge(HP). The sorption coefficient (Sorption, %) was used as a quantitative characteristic of the interaction of sorbents with cesium, strontium.

The relevance of the study is caused by the need to get knowledge of the fundamental scientific problem – the ferromanganese precipitation of the World Ocean. Marine ferromanganese deposits are records of sedimentation conditions in the past as well as promising mineral raw materials. Their formation is carried out under various processes, which are reflected in the bulk and isotopic composition of ferromanganese deposits. Currently, the least studied region of the Pacific Ocean is its northern segment. The main aim of the research is to study Sr and Nd isotopic composition of the ferromanganese crusts from the northern Pacific, formed under low detrital influx. Methods: litho-morphology; x-ray diffraction – determination of the mineral composition; mass spectrometric – determination of the chemical and isotopic composition. Results. Ferromanganese deposits of the guyots of the northern part of the Imperial Range (Detroit, Suzei, Hanzei) and the Amliya, Rat and Stailmate fracture zones, as well as the Vulkanolog Guyot (Magellan Seamounts), as a comparative material, were studied. Based on the mineralogical and geochemical bulk compositions, the studied ferromanganese deposits are classified as hydrogenetic ferromanganese crusts. The strontium isotopic composition of the studied samples is in the range from 0,70797 to 0,70919 (average 0,70885), with most of the samples concentrated at 0,709. At the same time, the content of strontium changes almost three times from 660 to 1700 ppm. The dependence of the isotopic composition on the concentration is not observed. The displacement of 87Sr/86Sr occurs towards volcanic rocks, which reflects the high amount of quartz-plagioclase admixture in the sample. The isotopic composition of neodymium, in terms of εNd, varies in the range from –3,5 to –3,0, which corresponds to the modern deep seawater of the North Pacific. An increase in εNd to –2,3 corresponds to a sample with the maximum terrigenous admixture. The minimum value of εNd (–4,4) was found in the bottom layer of the ferromanganese crust from the Hanzei Guyot. This value corresponds to the Miocene North Pacific Deep water. This is a reason to believe that in the Miocene the formation of the bulk composition of the North Pacific ferromanganese crusts was under North Atlantic Deep Waters entering through the Panama Gateway. The end of North Atlantic Deep Waters delivery to the Pacific was finished about five million years ago.

Relevance. At present, the study of Suprasenomanian deposits, including deposits of the Lower Berezovskaya subformation of Cognac-Santonian age, composed of siliceous rocks, has moved from the category of theoretical interest to the category of practically important research. This is due to the fact that industrial gas content was confirmed at six sites (Van-Egansky – NB1 formation, Vyngapurovsky – NB4, Medvezhy – NB3–NB4, Novo-Chaselsky – NB3, Komsomolsky – NB1, Kharampursky – NB1). There are four layers of the Lower Berezovskaya subformation (the NB horizon), however, criteria for determining the boundaries of these layers have not yet been identified. In this paper, the substantiation of lithological-mineralogical and commercial-geophysical criteria for stratigraphic dissection of the section of the Nizhneberez subformation is given. The object of the study is the Berezovskaya formation, which deposits in the north of Western Siberia contain significant gas resources, considered as a reserve for «prolonging the life» of deposits during the development of highly productive Cenomanian deposits. The aim: improving the efficiency of geological exploration to identify gas deposits in siliceous rocks of xenon by clarifying the stratigraphic structure of the rocks of the Berezovskaya formation. Methods. The dissection of the sections was carried out on wells drilled in recent years, with continuous core sampling and with an expanded complex of geophysical studies of wells (GIS), including electrical, radioactive, acoustic, nuclear magnetic methods. The mineral composition was determined by studying the core by X-ray diffraction analysis (more than 300 samples), infrared spectroscopy (220 samples). The composition of chemical elements in rocks was determined by X-ray fluorescence analysis (more than 300 samples) and inductively coupled plasma mass spectrometry (70 samples). Results. It is shown that the boundary between the NB2 and NB3 layers does not have unambiguous GIS criteria. At the Medvezhye field, this boundary is determined by the abrupt change in the readings of the nuclear magnetic and acoustic logs, at the Vyngapurovskoe field such abrupt changes in the curves of these methods are not noted. The paper shows that the boundary between the B3 and B2 layers has a clear characteristic of the mineral composition of rocks and is determined by a sharp decrease in the proportion of zeolites (clinoptilolite) during the transition from NB3 to NB2. Along with a decrease in the content of clinoptilolite at the boundary between the B3 and B2 layers, there is also a sharp change in the chemical composition of rocks, in particular, a sharp decrease in the proportion of strontium is noted. This tendency to decrease the proportion of clinoptilolite and strontium in rocks can be explained by the attenuation of volcanic activity in the south-east of Western Siberia.

Sr-substituted tricalcium phosphate was obtained by precipitation from aqueous solutions. Synthetic solid phases were investigated using X-ray phase analysis, IR spectroscopy, scanning electron microscopy, energy dispersive analysis. The supernatant was examined for the presence of Ca^2+ and PO4^3- ions to calculate the Ca/P ratio. It was revealed that strontium ions are part of tricalcium phosphate, but do not change its phase composition. The addition of strontium ions to the initial solution contributes to a decrease in the size of crystallites and an increase in their porosity. When studying the bioresorbability of the obtained samples using direct potentiometry, it was found that the samples containing strontium ions in their composition have a lower value of the rate of resorption. Energy dispersive analysis data confirmed that strontium ions are included in the composition of TCP samples. But with an increase in their concentration, complete replacement of calcium ions with strontium ions in the TCP structure does not occur. At the same time, the highest values of the dissolution rate are recorded in acidic media.

The strontium (Sr) and barium (Ba) profiles in otoliths of juvenile sockeye salmon Oncorhynchus nerka from British Columbia are measured using a Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) system and analyzed. The highest possible measurement resolution (near-daily) was used to assess variability and repeatability of the breakpoint (marine entry) estimates inferred from Sr:Ca and Ba:Ca ratios. Such resolution for the otolith chemical composition (to an accuracy of 2 μm) was reached using the rotating slit, which width was close to the daily circulus width of the otoliths. So, daily or 2-day changes in the elemental composition were recorded during the period of transition to the marine environment. Sr profiles were generally similar among the fish, starting with low values of Sr:Ca in the fresh water and increasing sharply after the marine entry. The Ba:Ca signal was more complex, showing in most cases a dramatic increase immediately before the breakpoint. Besides, multiple peaks in the Ba profiles were recorded prior to the marine transition with a significant difference of their number between fish from different populations. A breakpoint was detectable in the Ba profiles 3–11 µm prior to its appearance in the Sr profiles. The complexity of Ba profiles may cause erroneous estimates of the marine entry date; thus, the Sr signal is a more reliable marker of marine transition for juvenile sockeye.

The aim of the present work is titanium silicate influence on the zinc and strontium migration in the aquatic environment. The adsorption capacity of titanium silicate toward zinc and strontium ions was investigated. With the aid of a fluorescent X-ray analyzer and energy dispersive spectroscopy the composition of the sorbent formed was determined as well as zinc and strontium presence on the surface of the sorbent after the sorption process. It was shown, that adsorption of zinc and strontium by titanium silicate strongly depends on time of interaction and solution acidity and increases with increasing of both parameters. It was established, that for the initial concentration of zinc and strontium at the level of 0.005M the presence of ions that cause the natural mineralization of water does not affect their adsorption extraction.

The results of an experimental study of the effect of strontium on the anodic behavior of the Tsam 4-1-2,5 alloy in the NaCl electrolyte medium are presented. It is shown that strontium additives reduce the corrosion rate of the initial alloy Tsamsv4-1-2.5 by 10 %. With an increase in concentration of chloride ion in the NaCl electrolyte, the corrosion and pitting potentials shift to the negative region, and the corrosion rate increases.

Introduction Osteoporosis is a disease causing high morbidity with increasing prevalence. It is one of chronic diseases caused by reduced bone mass that subsequently decreases bone strength and increases fracture risks. Pharmacologic treatments for osteoporosis include antiresorptive agent (bisphosphonate) and bone-forming agent (strontium ranelate), so further research is needed to compare these two medications. Objectives We aimed to histopathologically compare bone density in post-menopause white rats after being treated with strontium and ibandronate. Material and methods 45 ovariectomized female rats were divided into three groups. The subjects in the first group were only ovariectomized (control). The strontium group was given daily oral strontium at a dose of 625 mg/kg BW/day for 60 days. The ibandronate group was given one subcutaneous ibandronate injection at a dose of 1 μg/kg BW/day for 60 days. We measured osteoclasts, osteoblasts, trabecula area and cortical thickness. Results The animals in ibandronate and strontium groups showed a significant increase (p < 0.005) in osteoblasts and significant decrease in osteoclasts compared to the control group. The subjects in both groups had a significantly thicker cortex and a larger trabecula area than in the control group. The subjects in the strontium group had more osteoblasts and thicker cortex than in the ibandronate group. Conclusion Strontium had a double effect, increasing osteoblasts and inhibiting osteoclasts. On the other hand, ibandronate had only a strong antiresorptive effect, but a lower osteoblast effect. It could be inferred that strontium was more effective in increasing bone density as compared to ibandronate.

Research subject. A section of the Upper Lochkovian (Lower Devonian) Valgan Formation located in the stratotypic area on the Ilych River, Northern Urals, was investigated.Materials and methods. A study of the composition and structure of rock samples gathered from the section under consideration during fieldwork in 2015 was conducted.Results. The studied section with an exposed thickness of 51 m is characterized by the thin and uneven alterations of calcareous con-glogravelites, coarse-grained and fine-grained organic sandsones, bioclatic-pelitomorphic limestones and argillo-calcareous shales. These rocks demonstrate a gradational and convolute lamination. An individual interval of the studied section contains calcareous conglobreccias layers. The Valgan Formation is characterized by a cyclic structure, with the thickness of individual cyclites ranging from 5.0 to 25 cm. The character of their structure testifies to sedimentation in slope settings. An analysis of clastic material revealed two sources of the basin area formation: near ablation (represented by the fragments of background bioclastic-pelitomorphic limestones) and remote ablation (represented by biohermal rock clasts). It is proposed to consider the Valgan Formation as the Valgan gradation, which extends the Upper Lochkovian sulfate-carbonate Subformation to the east.Conclusions. Therefore, the Valgan gradation should be treated as an intermediate link between shallow-marine Upper Lochkovian biohermal structures and bathyal clayey and siliceous shales.

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The article deals with the study of sorption (under batch conditions) of cesium and strontium radionuclides from sea water with ferrocyanidic sorbents based on hydrated titanium and zirconium dioxides (Т-35, NPF-HTD), glauconite and clinoptilolite natural aluminum silicates (NPF-G, NPF-C), zirconium phosphate (Т-3А), modified hydrated zirconium dioxide (Т-3К), and manganese dioxide based on hydrated titanium dioxide (MD-HTD). We have obtained the sorption isotherms, defined the cesium and strontium distribution coefficients. Dependences of the cesium distribution coefficient by the sorbents in seawater saline content have been obtained. The authors recommend NPF-G and NPF-HTD sorbents for treatment of liquid radioactive waste based on seawater with various salt content. Coefficients of the cesium distribution between solid and liquid phases were 1,0∙105 and 1,0∙104 mg/l, respectively, even at solutions with the salt content of 100 g/l. In the process of strontium sorption from seawater, the strontium distribution coefficients do not exceed 1,9·102 ml/g, this is connected with big proportion (34±7 %) of stable colloidal forms of strontium in the simulated seawater.

The substitution conditions of scandium atoms in SrLaScO4 slab perovskite-like structure (SPS) of Sr1–xCaxLaScO4- type (0 ⩽ x ⩽ 0,3) have defined by X-ray powder diffraction methods. SPS (Abma space group) of Sr0.7Ca0.3LaScO4 phase with a substitution degree of strontium atoms equal 0,3 is determined by the Rietveld procedure. The crystal structure of Sr0.7Ca0.3LaScO4 is formed by two-dimensional perovskite-like blocks consisting of a slab of distorted ScO6 octahedra joined by vertices. Blocks are separated by the slab of (Sr, Ca, La)О9 polyhedra. Analysis of the obtained data has shown that, in a case of the substitution of Sr atoms by Ca atoms in SPS of Sr1–xCaxLaScO4, a gradual reduction of the length of the (Sr, Ca, La) — О2 interblock bond and the increases of the deformation degree (Δ) of interblock (Sr,Ca,La)О9 polyhedra and the mutual inclination of octahedrons ScO6 take place. Reduction in the distance between perovskite-like blocks approaches a construction of SPS to the thermodynamically stable perovskite structure, and the increase of Δ(Sr, Ca, La)О9 strains and destabilizes SPS. The total effect of these factors leads to the destruction of SPS, limits the range of Sr1–xCaxLaScO4 solid solutions with a slab perovskite-like structure (0 ⩽ x ⩽ 0,3), and makes the formation of SrLaScO4 scandate with this type of structure impossible. The results obtained can be used to regulate the functional (electrophysical, optical, etc.) structurally dependent properties of the Sr1–xCaxLaScO4 phases by successively isovalent substitution atoms in the A-positions of their layered perovskite-like structure.

Soils of the southern region of Chad are developed on wind-drawn sand and colluvio-alluvium deposits of two main rivers Logone and Chari. This region of Chad is principal agricultural zone of Chad. Evaluation of physical and chemical properties of sandy soils and their fertility in this region revealed that some soils have very high content of strontium. With aim to locate areas with high content of srontium in soil, and to study its dependence on physical properties of soil and translocation of strontium in soil profile nine pedons were dug on different fields intensively used for agricultural production. Using X-ray spectrometric analysis and radiometric measuring of soil samples it has been revealed that Sr content in soil samples varies from 10 to 270 mg/kg of soil depending on type of soil, depth of soil layers, clay and organic content. Strontium content negatively correlates with total content of calcium and phosphorus in layers of soil. Low CEC of soil may be a reason of translocation of strontium from higher to lower layers of soils. Strontium content in soils do not relates with level of radioactivity of soils under study. The highest content of strontium has been found in soils developed on colluvio-alluviumdeposits. Very wide Ca/St ratioin soil samples of alluvial hydromorphic soils may cause increase of Sr content in vegetable food and drinking water. This may be one of etiological factors which directly or indirectly may cause misbalance in mineral nutrition and severe diseases of a man. It worth of considering necessity of further studies of Sr dynamic in soils under different crop production systems and how to mitigate negative effect of natural pollution of soils with this element.

Evaluation of the immune system parameters can be used in order to assess capacity to adapt under conditions of increased external chemical load, including exposure to metals, which can exert either activating and inhibitory effects upon immune regulation parameters. The aim of this work was the analysis of immunoregulatory markers in a children’s population who consumed water with high strontium content (a sample from the Perm region). We carried out immunological evaluation of the children aged 7 to 12 years, living at a territory with a high strontium content in the drinking water. The comparison group included children from the conventionally clean region. We studied differential changes in cellular immunity (phagocytosis rates), humoral factors of immune defense (serum immunoglobulins), development of specific sensitization for strontium, as well as the processes of apoptosis triggering and regulation. A 3.68-fold increase in strontium levels was shown in fresh water within observation area, and the average blood strontium content in the children of appropriate observation group was 1.55-fold higher than in children of the comparison group. At the same time, 1.2-fold increase in phagocytic activity determined as phagocytic number and phagocytic index was found, as compared to the control group. In 80% of the subjects, a reduction in serum IgG level was observed when compared to physiological norm, as well as a significant decrease in IgG and enhance in IgM production against the levels found in the comparison group. Wehave also shown an enhanced total sensitization in 55.0% of the observation group as shown by the total IgE test compared with normal age ranges, as well as excessive specific sensitization to strontium by 2.49 times, according to the IgG criterion. Disturbance in apoptosis triggering was associated with decreased number of CD95+ lymphocytes and TNFR1+ cells (2.8-fold compared to reference values), shifted balance in apoptogenic proteins, an average of 2.6-fold decrease in Bcl-2 expression, a 2.8-fold reduction of the p53 transcription factor expression relative to the reference interval. Thus, we have shown an ability of strontium excess in drinking water to influence the most important indices of immune regulation in pediatric population. These changes may serve as indices of populational health status under of external strontium exposure.

The anodic behavior of a lead-antimony alloy (3 wt% Sb) doped with alkaline-earth metals was investigated in potentiostatic method in the potentiodynamic mode at a potential sweep rate of 2 mV/s and it was shown that with an increase in the content of alkaline earth metals in the alloy (SSUZ), the potentials of free Corrosion and pitting are slightly shifted to the positive region. As the concentration of the chloride ion in the electrolyte increases, these potentials decrease. The current density of corrosion and, accordingly, the corrosion rate of alloys with an increase in the content of alkaline earth metals are reduced by 75–85%, and the concentration of chloride ion increases.In transition from alloys with calcium to alloys with strontium, the corrosion rate of alloys increases by 20–30%, and to alloys with barium it decreases by 25–30%.

A sequencing of the candidate genes of the pupils, exposed to strontium by the method of targeted resequencing has been performed. It is shown, that under conditions of increased revenues of strontium in drinking water the number of polymorphonuclear altered portions of candidate genes increases. As a result of the targeted resequencing in conditions of strontium exposure, the maximum polymorph modifications of the following genes are defined: sulfotransferase 1A1 (SULT1A1) and methylenetetrahydrofolate. It was shown that the structure of the mutations in conditions of the strontium exposure was characterized by the formation of defects in the gene mapping detoxification (38.5 % of all mutations) and immunoregulation (22.5 %). Analysis of the cause-effect relationships in the system "factor - the number of mutations" revealed that candidate genes reflecting strontium exposure conditions (content of strontium in drinking water is 1.3 MAC), are genes: cytochrome P450, glutathione - transaminase (detoxification); dopamine (CNS), interleukin 17 and the major histocompatibility complex (immune system), methylene-tetra-hydro-folate-reductase (reproduction).

After the Chernobyl disaster in 1986 large areas of agricultural land were contaminated with radionuclides. Most of them had short periods of half-life time and are inactive now. However several radionuclides with relatively long periods of half-life time – especially 137Cs and 90Sr are not. Even small amounts of them still may be dangerous both plants and animals due to low-dose effect. In this paper we study impact of silicon-containing mixtures (nanoparticles of tripoli and analcime mixed with sapropel and peat) on the migration rates of 137Cs and 90Sr in soil-plant system. In order to conduct the research we chose the experimental plots located in Kyiv Polesie on Gleyic Phaeozems (0-20 cm). Humus content was 1.48±0.51 %, рНKCl 4.91‑5.08. 137Cs and 90Sr contents were determined by ICP-MS method. Nonparametrical statistical analysis of experimental data was made. The difference was considered significant when P < 0.05. In the course of research we have found that application of the proposed mixtures leads to the immobilization of cesium and strontium in soil and significantly reduced their activity in plants by over 35 %. We suggest this fact to be caused by accumulation of sols of polysilicic acids in soil according to the scheme: (SiO2) x + 2H2O ↔ H4SiO4 + (SiO2) x-1, 2H4SiO4 → (HO)3SiOSi (OH)3 + H2O. Additional experiments are needed to determine whether partial dehydration of these sols due to summer droughts may intensify transport of radionuclides from soil to plants. To conclude, application of the mixtures that consist of nanoparticles of tripoli and analcime mixed with sapropel and peat slows down the migration rates of 137Cs and 90Sr from soil to plants on Gleyic Phaeozems.

The evaluation of immunological markers in schoolchildren exposed to strontium is performed. It is shown that under the conditions of increased administration of strontium with drinking water the indication of spontaneous and induced levels of neurotransmitters in vitro allows to detect early functional disorders of the immune system. It was found that the following markers of specific hypersensitivity and mediators of intercellular immune regulation (IgG specific to strontium, cytokines IL-6, IL-10, IL-12, IL-17, α-TNF, GM-CSF, spontaneous and specifically stimulated, RANKL, OPG( may be proposed for the identification of health risk as early markers of immune disorders in school children living in areas of strontium geochemical provinces.

Nonradiochemical method of measurement of 90Sr and137Cs activity in environmental samples is proposed. This method is based on spectrometrical investigation of electrons accompanied the decay of the 90Sr and137Cs. Accounting for the contribution to the total activity of the samples from the zones with the density of the contamination 1 - 5 Кu/km2 the 40K electrons allowed to improve the accuracy of the measurements for the samples of small rodents up to 15 - 20 % (the ratio of A (137Cs)/A (90Sr) was from 2 to 100), for samples of soil up to 10 - 15 % (the change of activity in these samples was ten thousand times). The results of the spectrometric measurements were confirmed by the traditional radiochemical research.

In areas with intense economic activity showed a significant variety of forms of man-made ecological imbalance in the geological environment, as well as a manifestation of the natural geological environment of negative processes caused by groundwater. They give rise to environmental changes, both global and local scales. The degree of risk is determined to a large extent the processes taking place en masse in the geological environment, as a rule, have an inertial character and hidden from direct observation. For the first time for groundwater of Orel region is set by a previously unknown contaminant natural character due to the advancement of strontium in the groundwater complex, and is composed geofiltration model that allows to carry out prediction of the front of strontium in 27 years. Developed a model of the radial pull of nitrate intake group to establish the pathways of contaminant in water wells.

Researches of vertical migration of Chernobyl origin radionuclides at testing «Red forest» area in 5-km ChNPP-zone were carried out. The γ- and β- spectrometer measurements of soil samples were carried out using the anticompton spectrometer and a beta spectrometer. Presence of 60Co, 134,137Cs, 154,155Eu, 241Am to depth of 30 cm in all soil cuts was fixed. The sites with sod-low-podzol sandy soils on alluvial sands contain 137Cs, 90Sr and 241Am to depth of 60 cm. The presence 243Am and 243Cm was found in the top layers of soils at territory of testing area.

The process of decontamination of liquid radioactive wastes, containing Cs-137 and Sr-90, by the sorption method using clay sorbents, modified by copper and copper-potassium ferrocyanides, and also antimony hydroxide was studied in the paper. The adsorption capacity of samples of the modified clay in the presence of equipment corrosion products, ions of cobalt and manganese, was studied. It was found that the modified clay sorbents are effective in the process of decontamination of liquid radioactive wastes since Cs-137 is removed by 99-100% and Sr-90 - by 70-97%. Ions of cobalt and manganese do not inhibit the adsorption of Cs-137 while the adsorption of strontium is reduced by 5-10%. Based on the analysis of results of adsorption of Cs-137 in the presence of cobalt, the hypothesis on a significant adsorption capacity of modified clay samples on cobalt was stated. [ABSTRACT FROM AUTHOR]

Results of the study of 90Sr and 137Cs migration mobility in soils characterized with contrasting physical-chemical properties and granulometric composition has been analyzed. The mentioned radionuclides were introduced in soils in initial water-soluble form. Ecological and effective half-time of cleaning of soils 20-cm horizons (Tecol) has estimated. Mean values of Tecol 90Sr varies in limits 3.7 - 84 years. Tecol 137Cs varies in limits 61 - 265 years. Correlation of ecological half-time cleaning of soddy-podsolic soils species from radionuclide and physical-chemical properties and granulometric composition of these ones has been analyzed, strong correlation of Tecol 90Sr as well, as mean correlation of Tecol 137Cs with mentioned soils characteristics has been noted. [ABSTRACT FROM AUTHOR]

Nonradiochemical method of measurement of 90Sr and137Cs activity in environmental samples is proposed. This method is based on spectrometrical investigation of electrons accompanied the decay of the 90Sr and 137Cs. Accounting for the contribution to the total activity of the samples from the zones with the density of the contamination 1 - 5 Ku/km2 the 40K electrons allowed to improve the accuracy of the measurements for the samples of small rodents up to 15 - 20 % (the ratio of A (137Cs)/A (90Sr) was from 2 to 100), for samples of soil up to 10 - 15 % (the change of activity in these samples was ten thousand times). The results of the spectrometric measurements were confirmed by the traditional radiochemical research [ABSTRACT FROM AUTHOR]

Sorption of uranium with amorphous spherically granulated sorbents based on phosphates of polyvalent metals, synthesized by sol-gel technology, occurs via ion-exchange-sedimental mechanism. By this reason proposed materials are suitable for a simultaneous decontamination of liquid radioactive wastes from cesium and strontium ions (via ion-exchange) and from uranium, americium and, perhaps, other transuranium elements presented in solution in anionic forms (via sedimental mechanism). Their efficiency has been confirmed during decontamination of liquid radioactive wastes. [ABSTRACT FROM AUTHOR]

Aim. To study the influence of zinc ions on the ATP-hydrolase reaction, catalyzed by myosin, and the superprecipitation (SPP) reaction of actomyosin cardiac muscle. Methods. Preparative protein chemistry, ion-exchange chromatography and optical spectroscopy. Results. It was shown that zinc ions in the range of concentrations 0.1-5 mM inhibit the Ca2+-ATPase myosin activity and Mg2+-dependent SPP reaction of actomyosin cardiac muscle. The original results were compared with the well-known data on the influence of other bivalent ions - strontium and cadmium - on the above processes. Conclusions. Zinc ions, probably by replacing the calcium and magnesium ions in the SPP reaction and ATP-hydrolase process, can modulate the actinmyosin interaction by changing the functional characteristics of muscle actomyosin macromolecules. The obtained results extend the existing understanding of the mechanisms of physical and chemical environmental factors influence, in particular metal ions, on the enzymatic activity of ATP-hydrolases, namely myocardium myosin ATPase. [ABSTRACT FROM AUTHOR]