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The results of the analysis of the current state and dynamics of concentrations of heavy metals and oil products in the soils of Belarusian cities for the period from 1990–1995 to 2016–2021 are presented. It is based on the soil monitoring data in the cities of Belarus within the framework of the National Environmental Monitoring System in the Republic of Belarus and the results of a detailed soil-geochemical survey of the city of Minsk, carried out by the authors in 1990. The dynamics of the content of chemicals in the soils of cities was assessed by comparing the average concentrations for individual cities over the period under review and with comparison of the concentrations of chemicals in soil samples taken at the same sampling sites in the city of Minsk over a nearly 30-year period. It has been established that for most cities there is a tendency to accumulate zinc and oil products in the soil cover. There is a decrease in the content of lead in the soil in 46 % of cities and an increase in its concentration in 19 % of cities are observed. Similar to lead dynamic is typical for copper content in urban soils. It is shown that the annual average increase in the content of zinc in the soils of Minsk is 0.57 mg/kg per year, while the annual average decrease in the content of lead is 0.22 mg/kg per year.

The relevance and importance of underground gas storages for the energy security of the Republic of Belarus is denoted. The types of underground gas storage facilities in operation on the territory of the republic are indicated. The geological conditions of the Mozyr salt massif in the area of the mine workings are given. The features of the structure of the Mozyr salt dome are considered. Information about the rock salt deposits of the Zalessky layers suitable for creating caverns is given. Mining and geological conditions are described and favorable factors of an underground gas storage creation in rock salt deposits under the conditions of the Mozyr salt dome are denoted. Information about the screening effect of the roof strata is given. Mathematical modeling was carried out and the assessment of the suitability of the existing salt caverns is given. During the conversion of existing and the creation of new caverns, as well as in the process of their operation (injection-storage-selection) long-term sustainability to the effects of pressures emerging has been confirmed. Formulas for determination the maximum gas pressure limit, the permissible maximum and minimum operating pressure as well as the required span of the cavern are given. The test pressure range for determining the tightness of the caverns is indicated. The conditions for choosing the minimum operating pressure in the cavern as well as the safety margin factor in relation to specific conditions are determined. In fact, the suitability and prospects of creating underground gas storage facilities in the salt domes of the Pripyat trough have been confirmed.

Titanium is considered to be the most essential metal in the field of implantology. The main factors determining metal biocompatibility, among others, include the morphology and chemical composition of the titanium surface. Therefore, the aim of this work was to develop approaches to control the biological activity of the titanium surface by creating coatings that combine both an inorganic phase with a given morphology and organic molecules containing an integrin-selective peptide that regulate cell adhesion and proliferation. As such, we synthesized new c(RGDfC) derivatives of amino acid bisphosphonates (four examples) with different bisphosphonate anchors and maleimide linkers. These molecules were deposited on a highly developed porous surface obtained via the plasma electrolytic oxidation (PEO) of coarse-grained and nanostructured titanium. In vitro studies demonstrated the increase in the viability degree of mesenchymal stem cells and fibroblasts on the surface of coarse-grained or nanostructured titanium modified with PEO and a c(RGDfC) derivative of ε-aminocaproic acid bisphophonate with an SMCC linker. As a result, the use of conjugates of amino acid bisphosphonates with a cyclic RGD peptide for the modification of PEO-coated titanium opens the ways for the effective control of the biological activity of the metal implant surface.

In this paper we supplement the problem statement of synthesis of layered dielectric filters considered in our previous studies and based on the ideas of P.L. Chebyshev. Fundamental constraints for such problems on layer materials admissible for synthesis are included. A mathematical apparatus that significantly simplifies the classical approach and computational procedures for such problems while maintaining the mathematical equivalence of the results was developed. For the first time, the broadest approach to the layered media theory is substantiated for the case of piecewise continuous dependence of the dielectric and magnetic permeability. The proposed formulation of the synthesis problem is shown to lead to much more economical computational procedures as compared to the previously known computational procedures, keeping all other important constraints on the synthesis problem unchanged.

We develop a theory of anomalous elasticity in disordered two-dimensional flexible materials with orthorhombic crystal symmetry. Similar to the clean case, we predict existence of infinitely many flat phases with anisotropic bending rigidity and Young's modulus showing power-law scaling with momentum controlled by a single universal exponent the very same as in the clean isotropic case. With increase of temperature or disorder these flat phases undergo crumpling transition. Remarkably, in contrast to the isotropic materials where crumpling occurs in all spatial directions simultaneously, the anisotropic materials crumple into tubular phase. In distinction to clean case in which crumpling transition happens at unphysically high temperatures, a disorder-induced tubular crumpled phase can exist even at room-temperature conditions. Our results are applied to anisotropic atomic single layers doped by adatoms or disordered by heavy ions bombarding., 18 LaTex pages, 6 figures

Two procedures were suggested for preparing a micro-mesoporous zeolite of MTT topology (ZSM-23 type) with the molar ratio SiO2/Al2O3 = 100 in the presence of dimethylformamide as a template. The first procedure involves hydrothermal crystallization under the conditions ensuring the formation of nanosized crystals. The second procedure is postsynthetic treatment of the zeolite with a NaOH solution to increase the mesopore volume. Samples of ZSM-23 zeolites with the crystal size of 100–200 nm with improved textural characteristics (micropore volume up to 0.1 cm3 g–1, mesopore volume up to 0.70 cm3 g–1) were obtained in >85% yield based on the silica used. The acid characteristics of the synthesized samples are similar to those of the zeolites prepared using pyrrolidine, which is expensive and is not produced in Russia.

It is shown that laser modification of a nanometer titanium film can be used for precise control of the loss level in optical waveguides on lithium niobate substrates. Theoretical estimates of the change in linear losses at the level of 0.95 dB/mm were confirmed by experiments on local laser modification using radiation at a wavelength of 976 nm with a threshold intensity of 1 kW/mm2. The proposed method can be effectively used for precision adjustment of the characteristics of integrated optical devices, such as the modulation contrast of Mach–Zehnder modulators.

The mechanism of enhancing the interaction of optical radiation with a superconducting niobium nitride film on the surface of optical waveguides on a lithium niobate substrate using an additional cover layer with a high refractive index has been studied. It has been shown that adiabatic deformation of waveguide modes allows increasing the absorption of light in a superconducting film to the level of ∼1 dB/μm, which makes it possible to manufacture a single photon detector with a quantum efficiency of about 70% on lithium niobate.

The present study focuses on a new method for obtaining C2–C3 carbonyl compounds (ketones and aldehydes) by the gas-phase selective oxidation of a propane–propylene mixture using nitrous oxide (N2O...

Currently, 3D scanning technology is used for high-precision measurements and fixing the geometric shape of various objects. However, when creating a computer 3D-model as a result of processing the array of data obtained from the scanning process, may contain errors. Errors may related to the features of the studied object (material, weight, size, location), functional properties of the software used or they may be the low qualification of the software engineer involved in processing 3D scan data. The task of this work was a finding the technical solutions, which allows one to reconstruct the objects surface, recorded using 3D scanning in the process of creating their computer 3D models. We proposed to use the inverse distance method, which is used in biometry to improve the quality of reconstruction of the 3D surface of a human face. Experiments have shown that the result of the reconstruction makes it possible to increase the accuracy of creating 3D models by recovering gaps in the surface of an object that were made during the 3D scanning process. The proposed approach allows one to construct a 3D surface without solving the triangulation problem, which leads to a reduction in computational costs.

Zeolites of the MTT framework type (Si/Al = 30) have been synthesized using dimethylformamide as a template and by a template-free method (Si/Al = 24). The morphology, textural, and acidic properties of the synthesized zeolites have been studied by scanning electron microscopy, high-resolution transmission electron microscopy, N2 adsorption, IR spectroscopy of adsorbed pyridine, and temperature-programmed desorption of ammonia and compared with the properties of a commercial ZSM-23 zeolite (Si/Al = 24). Zeolite powders have been used to prepare ZSM-23+Al2O3 supports and then Pt-modified bifunctional catalysts, the properties of which have been tested in n-decane hydroconversion. It has been shown that the isomerization activity of the Pt/ZSM-23/Al2O3 catalysts is largely determined by the texture and morphology of the original zeolites.

Organosubstituted silica derivatives were synthesized and investigated as modifiers of block copolymers based on macroinitiator and 2,4-toluene diisocyanate. A peculiarity of the modified block copolymers is the existence in their structure of coplanar rigid polyisocyanate blocks of acetal nature (O-polyisocyanates). Organosubstituted silica derivatives have a non-additive effect on high-temperature relaxation and α-transitions of modified polymers and exhibit the ability to influence the supramolecular structure of block copolymers. The use of the developed modifiers leads to a change in the gas transport properties of block copolymers. The increase of the permeability coefficients is due to the increase of the diffusion coefficients. At the same time, the gas solubility coefficients do not change. An increase in the ideal selectivity for a number of gas pairs is observed. An increase in the selectivity for the CO2/N2 gas pair (from 25 to 39) by 1.5 times demonstrates the promising use of this material for flue gases separation.

The optical tuning of the power splitting ratio in an integrated optical Y-splitter fabricated on the substrate of a photorefractive lithium niobate crystal (LiNbO3) has been studied. The areas of the Y-splitter that are most sensitive to local external illumination are determined. Tuning of the splitting ratio by 2% was experimentally demonstrated, which can be effectively used to increase the extinction ratio in Mach–Zehnder modulators.

The influence of the type of organic template from the series: pyrrolidine, dimethylformamide, N-methylpyrrolidone on the physicochemical properties of zeolite of MTT structure (ZSM-23) was studied. The optimal composition of the reaction mixture and the synthesis conditions of ZSM-23 were determined for each template. The use of relatively inexpensive organic templates, dimethylformamide and N-methylpyrrolidone, makes it possible to obtain phase-pure zeolite of MTT topology with SiO2/Al2O3 ratio from 60 to 100, the acid characteristics of which are similar to zeolites obtained with pyrrolidine expensive and not produced in Russia. The synthesis with use of dimethylformamide allows obtaining zeolite ZSM-23 with a yield of more than 95% calculated in term of silica spent and improved texture characteristics: the micropore volume 0.08–0.09 cm3 g−1, the total pore volume 0.3–0.35 cm3 g−1. An analysis of the features of the syntheses with different templates exhibited that dimethylformamide can be considered as the most suitable for use in producing MTT zeolite (ZSM-23).

The results of petrological-geochemical and isotope-geochemical studies of the Late Pleistocene-Holocene lavas of the Kazbek Neovolcanic Center, one of the largest centers of youngest magmatism in the Greater Caucasus, are presented. It has been established that the volcanic rocks of the Kazbek center arise a continuous compositional series basaltic (trachy-)andesites(trachy-)andesitesdacites with a predominance of calc-alkaline intermediate and moderately-acid lavas. The obtained results indicate that the processes of fractional crystallization and mixing of melts had a leading role in the petrogenesis of the rocks. The crustal assimilation was of limited importance; its influence is noticeable only in the rocks of the earliest and late pulses of magmatic activity within the Kazbek center. The common crustal lithologies participated in the assimilation were presented by metamorphosed Jurassic sediments (mainly shales and sandstones), forming the foot of the Kazbek center, and Mesozoic mafic metamorphosed volcanites very rarely. The specific features of AFC processes during the development of the studied magmatic system (including the presence of noticeable amount of water in the melt, the leading role of Amp in the cumulus and the absence of Pl fractionation) led to the appearance of dacitic lavas with geochemical signs of adakites as an evolutional end-member. The volcanic rocks of the Kazbek center are derived from trachybasalt magmas, the source of which was presented by the mantle reservoir of OIB-type. Recent and previously published results of studies of the Neogene-Quaternary magmatism manifested within the Greater Caucasus show that the main petrological and geochemical characteristics of this regional mantle reservoir remained constant from the end of the Miocene to the present time.

The deep processing of heavy oil increases the production of hydrocarbon gases. The resulting butanes do not always find an equivalent market. A mixture of oxygenates with a high octane number is obtained in this work via oxidation of industrial isobutane fraction. The reaction proceeds both in with and without using Au/Silicalite-1 and Cu/SiO2 as catalysts. The influence of factors that reduce the formation of undesirable impurities (hydroperoxides, peroxides, and acids) is studied. Tert-butyl alcohol (TBA) obtainable with a selectivity of 64–69% and butane conversion of 55–69% is a target product. TBA has a RON of 113. Alcohols and ketones having RONs within 106–115 appear together with TBA during the oxidation. The best result was obtained for a Cu/SiO2 catalyst. More than 18% of TBA and 2.9 times more ketones are removed from a unit volume of a reaction space in the presence of a catalyst than during oxidation without a catalyst. The total productivity of the products suitable as high-octane components is 40 g/(L h), while the RON of this mixture is ≈111. A mixture of oxygenates including TBA has a lower volatility than that of methyl tert-butyl ether, which is especially important for the stability of gasolines in summer.

The necessity of deep conversion of heavy oil gives rise to an increase in the production of hydrocarbon gases. The formed butanes are not always marketable. In the paper, the possibility of the production of high-octane oxygenate mixture via oxidation of the industrial isobutene fraction is discussed. The reaction was conducted in the absence and in the presence of catalysts such as Au/Silicalite-1 and Cu/SiO 2 . The factors were studied that allowed the formation of undesirable impurities (hydroperoxides, peroxides, acids) to be minimized. The target product was tert-butyl alcohol (TBA); it was produced at the selectivity of 64–69 % at the butane conversion of 55–69 %. RON number of TBA is 113. Along with TBA, alcohols and ketones with RON 106–115 were produced. The best result was obtained with the Cu/SiO 2 ; in the presence of this catalyst the yield of TBA was 18 % higher and the yield of ketones was as high as 2.9 times of the yields obtained by the noncatalytic reaction. The total yield of products to be used as high-octane reached 40 g/L·h, while RON was ca. 111 of this mixture. The mixture of TBA-based oxygenates are less volatile than methyl-tert-butyl alcohol that is of particular importance to provide gasoline stability in summertime.

The article describes modern solutions used to create vision systems for autonomous robotic complexes, a device for controlling video sensors, methods for obtaining stereo images, processing and further using them in the navigation system. A functional diagram of the organization of the robotic vision system, which is part of the NIIVK M. A. Kartsev Computing System Research and Development Institute, platform, a brief description of its functions and principles of action. The proposed solution involves placing a pair of optical sensors in the head of the robot, simulating the binocular stereoscopic vision inherent in higher animals. A feature of the development is the rejection of the use of laser, infrared, radio frequency, ultrasound and other active emitters, which reduces energy costs and the cost of products without reducing their reliability.

The oxidation of ethylene to acetaldehyde by N2O on Na-modified FeZSM-5 zeolite in a flow mode was studied at a temperature of 300 to 375 °C and with varying the feed mixture ratio N2O:ethylene:He from 5:5:90 to 5:95:0. It was found that in this range of conditions, acetaldehyde could be produced with selectivity up to 55%. Other reaction products were COx, coke and some amount of unidentified products, which were mostly the result of non-oxidative transformations of ethylene. To study the mechanism of the reaction, we used a quasi-catalytic mode in the temperature range 150–200 °C. The products accumulated on the surface during the reaction in the quasi-catalytic mode could be extracted from the surface and identified using various analytical methods. This approach allowed us to determine that the primary product of ethylene oxidation is ethylene oxide, which then isomerizes into acetaldehyde.

The structural and magnetic properties of YbMnO3 and Yb0.82Sr0.18MnO3 multiferroics were studied by neutron powder diffraction (NPD), magnetometry and electron spin resonance (ESR) technics in a wide temperature range. Neutron diffraction measurements showed that the substitution of ytterbium ions with strontium ions in hexagonal h - YbMnO3 (space group P63cm) leads to the destabilization of the crystal structure of the last compound and appearance of the mixture of three phases with different structure: hexagonal phase h - Yb0.95Sr0.05MnO3 (space group P63cm), orthorhombic phase o - Yb0.69Sr0.31MnO3 (space group Pbnm), hexagonal phase SrMnO3 (space group P63cm). This fact was proved by the ESR measurements in which a several signals due to the phases of different structure were observed. NPD measurements showed that the magnetic structure of h - Yb0.95Sr0.05MnO3 phase is similar to the magnetic structure of the pure h - YbMnO3 and demonstrate the presence of the antiferromagnetic ordering in the samples. ESR and magnetization measurements of h - YbMnO3 sample proved the presence of the antiferromagnetic correlations and also they showed the appearance of the ferromagnetically correlated nanoregions.

The paper reports the isotope-geochronological and petrological-geochemical studies of the Pliocene moderately-acid volcanism of the Akhalkalaki Plateau in the central part of the Lesser Caucasus (Javakheti highland, Georgia). K-Ar dating showed that young dacitic lavas and pyroclastic rocks were formed in the Mid-Pliocene (3.28 ± 0.10 Ma) in relation with the explosive–effusive eruptions of small composite volcanic cones and formation of minor extrusive domes confined mainly to the eastern margin of the region. Isotope-geochronological data in the combination with results of structural drilling indicate that the considered short-term pulse of the volcanic activity occurred during a short gap between two phases of the Pliocene–Early Pleistocene mafic magmatism widespread within the Akhalkalaki plateau. The studied Pliocene dacites were erupted at the post-collisional stage of the evolution of the Lesser Caucasus, but bear petrological-geochemical affinity of adakitic series. They are characterized by the steady presence of amphibole phenocrysts, the elevated contents of Sr, Ba, LILE and the lowered contents of Y, Nb, Ta, and HREE, and have depleted Sr isotopic composition (87Sr/86Sr < 0.7045). Analysis of petrogenetic models earlier proposed to explain the generation of adakite-like magmas in the modern collision zones showed that the origin of the Pliocene dacitic lavas of the Akhlkalaki plateau is best described by the crystallization differentiation of watersaturated calc-alkaline basaltic melts with removal of common mafic rock-forming minerals (first of all, amphibole and pyroxene) and accessory phases (apatite, titanite, Ti-magnetite) as cumulus minerals. Crustal assimilation of evolved magmas only insignificantly contributed to the petrogenesis of the dacites.

The paper reports the isotope-geochronological and petrological-geochemical studies of the Pliocene moderately-acid volcanism of the Akhalkalaki Plateau in the central part of the Lesser Caucasus (Javakheti highland, Georgia). K-Ar dating showed that young dacitic lavas and pyroclastic rocks were formed in the mid-Pliocene (3.28 ± 0.10 Ma) in relation with the explosive–effusive eruptions of small composite volcanic cones and formation of minor extrusive domes confined mainly to the eastern margin of the region. Isotope-geochronological data in the combination with results of structural drilling indicate that the considered short-term pulse of the volcanic activity occurred during a short gap between two phases of the Pliocene–Early Pleistocene mafic magmatism widespread within the Akhalkalaki plateau. The studied Pliocene dacites were erupted at the post-collisional stage of the evolution of the Lesser Caucasus, but bear petrological-geochemical affinity of adakitic series. They are characterized by the steady presence of amphibole phenocrysts, the elevated contents of Sr, Ba, LILE and the lowered contents of Y, Nb, Ta, and HREE, and have depleted Sr isotopic composition (87Sr/86Sr < 0.7045). Analysis of petrogenetic models earlier proposed to explain the generation of adakite-like magmas in the modern collision zones showed that the origin of the Pliocene dacitic lavas of the Akhlkalaki plateau is best described by the crystallization differentiation of water-saturated calc-alkaline basaltic melts with removal of common mafic rock-forming minerals (first of all, amphibole and pyroxene) and accessory phases (apatite, titanite, Ti-magnetite) as cumulus minerals. Crustal assimilation of evolved magmas only insignificantly contributed to the petrogenesis of the dacites.

A negative trend in power and public relations in Russiain the last year was the decline in public confidence in the authorities. One of the possible reasons for this is the dissatisfaction of citizens with the professional activities of civil servants, the distance of this institution from society. The public service is the main institution for the implementation of the functions of the state. Therefore, one of the important organizational tasks of public administration should be to ensure transparency and social acceptability of the activities of civil servants. Such a tool by its very nature is public control, but the Russian Federationhas not yet developed its legal framework and mechanisms, which determines the low efficiency of this institution of interaction between government and society. Despite a number of regulations adopted recently and aimed at increasing the transparency of public authorities, the desire of state bodies to conceal information from citizens remains. On the basis of the analysis of the forms of public control fixed in normative acts the reasons of its insufficient efficiency are revealed in the article. The authors put forward a number of proposals aimed at the development of the system of public control and designed to contribute, ultimately, to increase the legitimacy of the government as a whole, which is an urgent problem for Russia.

Local laser oxidation of a thin titanium film is considered as a means of a precise adjustment of losses and effective refractive index of dielectric optical waveguides. A fine phase control of an operating point and extinction ratio enhancement up to 57 dB were demonstrated using an integrated optical Ti:LiNbO3 Mach-Zehnder modulator. This technique only slightly affects the dielectric waveguide material and is very promising for a high precision permanent trimming of photonic devices based on dielectric waveguides of different material platforms and fabrication technologies., Comment: 15 pages, 10 figures, published in Optical Materials Express

Our work provides as review of Quaternary volcanic activity in the Greater Caucasus. In particular, we have focused our attention on the Elbrus (northern slope of the main range of the Greater Caucasus), Kazbek (central sector of the Greater Caucasus) and Keli (southern slope of the main range of the Greater Caucasus) volcanoes. After conducting detailed isotope-geochronological, geological and petrological-mineralogical studies regarding the above volcanic centres, we have been able to document multiple phases of volcanic activity: i) five phases have been defined for the Elbrus volcanic centre: I – 950-900 ka (andesite-basalts, trachyandesites and dacites), II – 800-700 ka (ignimbrites, rhyodacites, dacites and andesites), III – 225-170 ka (dacites), IV – 110-70 ka (dacites) and V phase – less than 35 ka (dacites); ii) four phases have been defined for the Kazbek centre: I – 460-380 ka (basaltic andesites and andesites), II – 310-200 ka (latest phase – andesites and dacites, earliest phase – basaltic trachyandesites, basaltic andesites, and dacites), III – 130-90 ka (latest phase – dacites, earliest phase – andesites and trachyandesites), IV – less than 50 ka (andesites and dacites); iii) for the Keli centre, three phases have been defined: I – 245-170 ka (dacites, rhyolites and andesite-dacites), II – 135-70 ka (earliest phase – dacites and rhyolites, latest phase – dacites, rhyolites, andesites and trachyandesites), III – less than 30 ka (dacites and andesites). Owing to the Holocene age of the latest phases of volcanic activity, these volcanic centres ought to be regarded as potentially active (dormant).

В статье изучается концепция гибридной войны, которая стала особенно популярна после обострения отношений между Украиной и Россией. К ее особенностям относят комбинирование традиционных и иррегулярных методов противоборства. На основе критического анализа доктринальных документов и экспертных оценок США и России делается вывод, что данное понятие не имеет устоявшихся определений ни в военной, ни в политологической литературе. На примере операции в Крыму 2014 г. показано, что в отношении России концепция гибридной войны используется западными экспертами в политизированном виде для отождествления гибридной войны с внешней политикой государства, доказывая ее милитаристский характер.

Investigation of reaction mechanisms by identifying the intermediates released into the gas phase is most effective at low conversion of reactants, ideally approaching zero. However, conversions below 0.5–1% are rarely used, due to the difficulty of analysis of low-concentration products. The mechanism of the title reaction is a subject of long-term discussion. We studied the mechanism using an original ultralow conversion (ULC) method. The idea is to perform the analysis of products after their preliminary accumulation in a suitable absorbent at the reactor outlet. This allows decreasing conversion by 2–3 orders of magnitude. The ULC experiments were conducted with a Bi–Mo catalyst at 100–250 °C and with propene conversion down to 0.001%. A new so-called allyl hydroxylation mechanism was revealed. A key step is the hydroxylation of the CH 3 group to form an allyl alcohol intermediate, which is further oxidized to acrolein. The mechanism explains all reaction features and was confirmed by experiments at 350 °C.