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The features of structural transformations of peat humic acids in the course of mechanical activation with iron oxyhydroxides and the changes in their surface-active and adsorption properties are revealed. It is shown that the maximum biological activity of the aqueous solutions of sodium humates is manifested when the concentration of the active substance of humic acids is below the critical concentration of micelle formation.

The chemistry of heterocyclic compounds has become one of the most dynamically developing fields of organic chemistry in recent decades. The role the heterocyclic compounds play in different areas of science and technology (chemistry, medicine, biology, electronics, etc.) can hardly be overestimated. In this regard, the development of new synthetic methods for functional derivatives of various heterocyclic compounds still holds relevance. Pharmaceuticals such as Trazodone, Nefazodone, Aprepitant, Itraconasole and others, which comprise the 1,2,4-triazol-5-one moiety, are widely used in modern medicine and pharmacy. The synthesis and characterization of the compounds of this series are of theoretical and practical interest. The design of novel drugs is based both on the directed synthesis of new drugs and on the screening of bioactive compounds derived by modifying the known drug molecules. Here we report two methods that give access to 3-nitro-1,2,4-triazol-5-one (NTO) alkyl derivatives, which is not possible via other common approaches. The success of our methods is due to the use of preparatively obtainable starting substrates and to the positional selectivity of all the reactions along a specified nitrogen atom. The strategy devised herein contributes to the progress in the theory of reactivity of ambident heterocycles and allows for selective synthesis of never-before-seen 1-substituted derivatives of NTO. The virtual screening of N-functionalized derivatives of 3-nitro-1,2,4-triazole and 3-nitro-1,2,4-triazole-5-one, which were obtained by the nucleophilic substitution of the nitro group, saponification and nitration, has shown their high biological activity in the most demanded areas of medicine - disease treatment, prevention and rehabilitation: cardiovascular diseases; diseases of the nervous system (neuromediators, neuroprotectors); anticancer drugs (cancer growth blockers). Therefore, such compounds arouse elevated interest among researchers in Russia and overseas.

For a long time, the inhabitants of the middle latitudes of the Earth mark annually recurring natural anomalies: at the end of May and beginning of June - a two-week return of cold weather, while at the end of September and beginning of October heat returns for the same couple of weeks. In time, these phenomena coincide with the beginning and end of photosynthesis in the respective regions. Although on average the plants on the planet spend only about 1% of solar energy for biosynthesis, we tried to prove that from the point of view of biophysics, these are strictly interrelated natural phenomena, and the beginning and end of plant biosynthesis can lead to a jump in air temperature in the surface layer by 5-10 degrees.

The possibility of obtaining a polydisperse porous material from the birch bark bast with subsequent separation into an enterosorbent and a porous substrate is demonstrated. A technological scheme is developed for processing birch bark bast, which allows one to obtain polydisperse porous material with the yield of 43.5 %. It is proposed to use the fraction of the size less than 0.25 mm as an enterosorbent, and the fraction of 0.25-1.0 mm as a porous substrate to obtain biocomposite fertilizers. It was established that the enterosorbent from birch bast is not inferior in its properties to the industrial enterosorbent "Polyphepan" from hydrolytic lignin. It is shown that, on the basis of the porous substrate, it is possible to obtain a complex biocomposite fertilizer with a growth-promoting effect and increased resistance to the washing out of active components by water. Slow leaching of macro- and microelements from the fertilizer determines the effect of its prolonged action. Thus obtained fertilizer is superior in its resistance to leaching of phosphates and potassium to the industrial granular fertilizer brand "Kemira Universal-2". Taking into account the particle size, lignin content and swelling ability, the porous substrate can also be used as a structuring additive in the soil. To obtain porous materials from the birch bark bast for various purposes, the enlarged plant is proposed, which allows processing up to 12 kg of the raw material in one technological cycle.

Results of the field studies of the snow cover composition around dumps and a highway of the Gorlovka coal deposit are presented. The prevailing element in technogenic dust is carbon. The concentrations of almost all the elements in the dissolved and suspended parts of the snow cover exceed background values. The migration ability of the elements in snow samples collected near the dump and near the highway are similar. However, the distribution coefficients of the elements in snow samples from the highway region are lower, which is the evidence of their transfer in more mobile forms here. The influence of the Gorlovka anthracitic deposit on the surface layer of the atmosphere extends to more than 1000 m. At the same time, the highway along which the extracted coal is transported has a stronger influence on the state of the atmosphere than the dump for overburden and host rocks. The shielding effect of forests located along the road is shown.

A limited life span of endoprostheses in the absence of other complications is explained by the aseptic implant instability arising and developing as a result of insufficient osteointegration. The surface of implants made of the VT-6 alloy was treated to form calcium phosphate coatings including those containing germanium (0.4 and 2.5 mass %), for the purpose of carrying out a comparative analysis of the response of an organism. The surface of the resulting coatings was investigated by means of scanning electron microscopy. It was established that the introduction of germanium has a substantial effect on the surface morphology of the coatings. It was shown with the help of the light microscopy of histological sections that osteointegration processes are most intense with the group of implants containing germanium at a level of 2.5 mass % in the calcium phosphate coating.

One of the main requirements for tantalum oxide semiconductor capacitors is the reduction of the equivalent series resistance (EPS), the value of which is directly related to the electrical conductivity of the semiconductor manganese dioxide layer formed on the surface of the tantalum electrode. Analysis of the current state of the production of electrolytic capacitors in Russia showed that the industry survives a steady trend towards an increase in switching frequencies from 10 to 100 kHz and higher, necessitating a reduction in the EPS of the finished capacitor. At the same time, manufactured products do not have the necessary characteristics for operation at higher frequencies. Existing technology solutions do not provide the production of high-quality capacitors, since they are multistage, energy-intensive and require continuous improvement. This paper deals with the search for ways to improve the electrical characteristics of a manganese dioxide cathode coating on tantalum oxide semiconductor capacitors. A theoretical analysis of the literature was conducted in order to determine the probable causes of the increased equivalent series resistance of a capacitor. The properties of factory-made tantalum oxide semiconductor capacitors were investigated by means of X-ray phase and photomicroscopic analysis; their electrical parameters were determined. It was shown that an increase in the equivalent series resistance of capacitors is due to the presence of an impurity of high-resistance manganese oxide (III) in the composition of the cathode coating based on manganese dioxide. It was established that manganese oxide (III) contaminates the impregnating solution of manganese nitrate, from which the cathode coating on tantalum bulk-porous anodes is obtained by thermal decomposition. To reduce the EPS of the finished capacitor, a method is developed for removing manganese oxide (III) from the semiconductor coating by cleaning the precursor, manganese nitrate, and modifying the surface of the cathode coating with oxidizing agents. The proposed method can be recommended for practical implementation in the production of tantalum oxide semiconductor capacitors, which will improve the electrical characteristics by reducing the equivalent series resistance of finished products.

The changes in the composition of the residual fractions and the structure of the asphaltene molecules during the primary processing of heavy oil are investigated. It was established that the atmospheric-vacuum distillation of heavy oil is accompanied by the formation of additional resin-asphaltene substances (more than 20 mass %). The initiation of chemical reactions between oil components occurs at the stage of fuel oil production due to the destruction of mainly sulphur-containing fragments in asphaltene molecules. It was shown that during tar production, the destruction and elimination of asphaltene-saturated fragments occur with a decrease in the content of naphthenic and paraffinic carbon by 5.5 and 1.7 %, respectively. Recombination reactions between the resulting macroradicals of asphaltene molecules contribute to an increase in their aromaticity factor by 7.2 % and the average molecular mass by 190 Da. Collection of the fraction 350-450 °C leads to a decrease in the average molecular mass of asphaltenes by 425 Da with an insignificant redistribution of carbon in various structural fragments.

Processes occurring in the dumps of sulphide-bearing rocks had drawn the researchers' attention for a long time. Environmental hazards connected with the activity of mining industry facilities under the conditions of climate change can be estimated by modeling. Modeling was performed in the water-rock-atmosphere systems (software suite Selector), where rock is an average mineral composition of rocks from the Allarechensky Deposit Dumps of copper-nickel ores. The conditions for the carryover of different components during weathering of rocks in the dump were determined, and the effect of climatic factors on the formation of new phases was evaluated. It was demonstrated that abrupt temperature changes promote rock weathering. In addition to copper and nickel, potassium and aluminium will pass into solution during the cold period. Gibbsite and aluminium silicates will be formed during the warm period. Comparison of modeling results with field studies revealed the adequacy of the model and high degree of the interaction of rocks and atmospheric precipitation in the dumps. Evaporation gives rise to more acid solutions, increased transfer of nickel, copper, iron and sulphates into solutions. The basic premise is that the destruction of wastes mineral matrix occurs practically all the year round under the regional climatic conditions, due to the formation of highly mineralized solutions inside the dump body and on its surface. Atmospheric precipitation, filtered through rock fragments with high sulphide content, affects the hydrosphere causing an increase in the concentration of all the major ions (Clˉ, SO₄²ˉ, HCO₃ˉ, Na⁺, K⁺, Ca²⁺, Mg²⁺) by a factor of several units, compared to pure natural waters.

The effect of ionizing radiation on bituminous coal samples was studied. It was established that pre-treatment of coal leads to an increase in the amounts of oxygenated and asphaltenic fractions in extracts. The effect of ionizing radiation on subsequent thermal destruction of coal was shown. In the process of coking of the treated and extracted coal samples, the yield of coke residues with macroporous structure increased.