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New spiropyrans with chromene and indoline cores bearing alkoxycarbonyl group and cationic π-acceptor in the chromene moiety were synthesized in one step from 1,2,3,3-tetramethylindolinium and isophthalic dialdehyde derivatives. The appending of a 8′-positioned conjugated cationic fragment causes a significant red-shift of the photoinduced isomers absorption maxima and provides them with extremely long lifetimes up to 75 min. The obtained spiropyrans exhibit both positive and negative photochromism in solutions, demonstrating the properties of ‘photochromic balance’.

The objectives of the study are to determine the legal problems of peasant farm enterprises setting up, their activities and status. In the research process, legal, economic, mathematical and statistical methods were used. The article uses the comparative legal method, the method of analysis of legal norms, the method of interpretation of legal norms and the practice of judicial enforcement in conjunction with economic, mathematical and statistical methods. The authors point out the problem of dualism of peasant farms enterprises’ legal status; highlight the specific character of this legal form, which must be taken into account when adopting agricultural legislation.

The aim of the work is synthesis and study on the properties of polyfunctional magnetosensitive nanocomposites (NC) and target-directed magnetic fluids (MF) based on physiological solution (PS), magnetite, gemcitabine (GEM) and HER2 antibodies (AB), promising for use in targeted antitumor therapy against MDA-MB-231 aggressive tumor cells of triple-negative human breast cancer (BC) with high proliferative and metastatic activity. The specific surface area (Ssp) of samples was determined by the method of thermal desorption of nitrogen using a device KELVIN 1042 of “COSTECH Instruments”. The size of nanoparticles (NP) has been estimated by the formula DBET = 6/(ρSBET), where ρ is the density of NC particle, SBET is the value of the specific surface area calculated by the polymolecular adsorption theory of Brunauer, Emmett and Teller (BET). The surface condition of nanodispersed samples was studied by IR spectroscopy (“Perkin Elmer” Fourier spectrometer, a model 1720X). To calculate the concentration of hydroxyl groups on the surface of nanostructures, the method of differential thermal analysis was used in combination with differential thermogravimetric analysis. The thermograms were recorded using a derivatograph Q-1500D of MOM firm (Hungary) in the temperature range of 20–1000 °C at a heating rate of 10 deg/min. X-ray phase analysis of nanostructures was performed using a diffractometer DRON-4-07 (CuKα radiation with a nickel filter in a reflected beam, the Bragg-Brentano focusing). The size and shape of NP were determined by electron microscopy (a transmission electron microscope (TEM) JEM-2100F (Japan)). The hysteresis loops of the magnetic moment of the samples were measured using a laboratory vibration magnetometer of Foner type at room temperature. Measurement of optical density, absorption spectra and GEM concentration in solutions was performed by spectrophotometric analysis (Spectrometer Lambda 35 UV/Vis Perkin Elmer Instruments). The amount of adsorbed substance on the surface of magnetite was determined using a spectrophotometer at λ = 268 nm from a calibration graph. The thickness of the adsorbed layer of GEM in the composition of Fe3O4@GEM NC was determined by magnetic granulometry. To study the direct cytotoxic/cytostatic effect of a series of experimental samples of MF based on PS, Fe3O4 NP, GEM, HER2 AB, as well as MF components in mono- or complex use, onto MDA-MB-231 cells in vitro, IC50 index was determined. MF were synthesized on the basis of single-domain Fe3O4 and PS, stabilized with sodium oleate (Ol.Na) and polyethylene glycol (PEG), containing GEM and HER2 (Fe3O4@GEM/Ol.Na/PEG/HER2+PS). The cytotoxic/cytostatic activity of MF against MDA-MB-231 cells was studied. It was found that as a result of application of synthesized MF composed of Fe3O4@GEM/Ol.Na/PEG/HER2+PS at the concentration of magnetite of 0.05 mg/mL, GEM - 0.004 mg/mL and HER2 AB - 0.013 μg/mL, a synergistic effect arose, with reduction of the amount of viable BC cells to 51 %. It has been proved that when using MF based on targeted Fe3O4/GEM/HER2 complex, the increased antitumor efficacy is observed compared to traditional use of the drug GEM, with a significant reduction (by four times) of its dose. The high cytotoxic/cytostatic activity of Fe3O4/GEM/HER2 complexes is explained by the fact that endogenous iron metabolism disorders play a significant role in the mechanisms of realization of the apoptotic program under the influence of nanocomposite. Thus, when the nanocomposite system contains Fe3O4/GEM/HER2 complexes in MDA-MB-231 cells, a significant increase is observed in the level of “free iron”, which favours formation of reactive oxygen species and causes oxidative stress (Fenton reaction). The consequences of oxidative stress are induction of apoptosis, enhancement of lipid peroxidation processes, as well as structural and functional rearrangement of biological membranes. The prospects have been shown of further studies of Fe3O4@GEM/Ol.Na/PEG/HER2+PS MF in order to create on their basis a magnetically carried remedy for use in targeted antitumor therapy.

The purpose of the research, the results of which are reflected in this article, is to preserve, replenish and study the genetic resources of grapes at the Anapa zonal experimental station of viticulture and winemaking (AZESViW). Novelty. Anapa ampelographic collection, consisting of 4941 genotypes, in 2019 was supplemented with ten varieties (grafted culture): Viktor 2 (Simpatiya), Vion’e, Zarya Nesvyataya, Karmener, Marselo, Romeo, Rusbol muskatnyy, Sirius AZOS, Furshetnyy, Yubiley Khersonskogo dachnika. First identified 5 sources of breeding valuable traits: 2 source of large berries – table grapes Ryukho i Strashenskiy, 1 source of phylloxera resistance – universal grade Ananasnyy, 1 – high sugar content – a technical grade of Bastardo and 1 – ultra-early ripening – table grape Olimpiada. Methods. These varieties, as well as all those growing in the collection, are subject to comprehensive research every year using traditional and modern methods of study, including agrobiological accounting, testing, identification, phenology, crop accounting, growth, and so on. Results. According to the results of scientific research last year, a number of features of the reaction of the studied grape varieties of different ecological and geographical groups and maturation periods to atypical conditions of the growing season in 2019 were revealed. In addition, among the studied varieties, one source was allocated for phylloxerostability: Pineapple grape variety; two sources were allocated for large-yield-table varieties Ryuho (Ryuho) and Strashenskiy; one source for high sugar accumulation – technical variety Bastardo and one source for early maturation-table variety Olympiada. Practical significance. These sources of economically valuable breeding characteristics are necessary for the creation of new varieties, clones and hybrids of grapes that increase the stability of agrocenosis and stability of fruiting, the introduction of which in production can increase the profitability of growing grapes by increasing the quantitative and qualitative indicators of the crop.

The paper describes the preparation of a new salt spiropyran of indoline series containing vinyl-3H-indolium fragment in the 8' position of the 2H-chromene moiety and a chlorine atom in the benzene ring of the indoline fragment. The structure of the reaction product was studied by IR, 1H, and 13C NMR spectroscopy. The data of X-ray diffraction study indicate that the reaction leads to the partial exchange of the indoline hetarene fragment to provide previously described salt spiropyran containing no chlorine atom in the indoline portion of the molecule.

Background. Development of nutrient media ensuring the maximum growth rate of pathogens of dangerous infectious diseases while preserving their biological properties is extremely important. A promising direction in this area seems to be the use of synthetic microbial growth biostimulants.The aim of the work is to study the possibility of improving nutrient media for the cultivation of Listeria and Staphylococcus using a biologically active compound tris(2-hydroxyethyl)ammonium 4-chlorophenylsulfanylacetate.Materials and methods. The object of the study was experimental nutrient medium for the cultivation of Listeria used for the culturing of the test strain Listeria monocytogenes 766. As a comparison medium, commercial medium Fraser broth to which agar was added at a concentration of 1.5 %, was used. The test strain Staphylococcus aureus ATCC 6538-P (FDA 209-P) was cultivated on meat-peptone agar with 1% glucose. The compound tris(2-hydroxyethyl) ammonium (4-chlorophenyl)sulfanylacetate at a concentration of 10–4 wt. % was studied as a growth stimulator. A nutrient medium without a stimulant served as a control. The specific activity of nutrient media (germination rate, medium sensitivity, growth rate and stability of the main biological properties of microorganisms) was evaluated by the microbiological method.Results. Studies have shown that the addition of a growth stimulator to nutrient media contributes to the growth of colonies (by 10–50 %) and a decrease in the time of their development. When growth stimulator was added to the nutrient medium for the cultivation of Listeria, the initial growth of colonies of the L. monocytogenes 766 test strain after 12 hours of cultivation and growth of colonies of the test strain S. aureus ATCC 6538-P after 6 hours of cultivation on the meat-peptone agar with 1% glucose was observed.Conclusion. Thus, the addition of a growth biostimulator tris(2-hydroxyethyl)ammonium 4-chlorophenylsulfanyl acetate at a concentration of 10–4 wt. % in the nutrient medium accelerates the growth of Listeria and Staphylococcus, allows to reduce the time of issuance of the analysis result in half.

The surface states of Dirac fermions in p-Bi2Te3, p-Bi2 –xSbxTe3 –ySey, and p-Bi2 –x–ySnxGeyTe3 thermoelectrics were studied and its topological characteristics were obtained by scanning tunneling techniques in dependence on compositions. It was shown that the thermoelectric power factor and the material parameter enhance with the shift of the Dirac point to the top of the valence band with the increasing of atomic substitution in these thermoelectrics. A growth contribution of the surface states is determined by an increase of the Fermi velocity for large atomic substitutions of Bi at x > 1.5 and small substitutions in the Te sublattice (y = 0.06). In compositions with smaller substitutions at x = 1–1.3 and y = 0.06–0.09, similar effect of the surface states is determined due to raising the surface concentration of charge carriers.

This review provides information on major organochlorine pesticides (OCPs), which were applied in agriculture worldwide in the 1940s–1960s and are still in use in some developing countries (such as India and China). Patterns of their distribution in the environment, toxicity, metabolism, and degradation are described. Their distribution over the components of ecosystems in different regions of the World Ocean, including the Far Eastern seas of Russia (the Sea of Japan, the Sea of Okhotsk, and the Bering Sea), is characterized over the period of 2000–2016. In the Sea of Okhotsk and the Bering Sea, the OCP content of marine organisms is lower than that in other regions of the World Ocean, in particular, in the Sea of Japan. Results show that a pesticide “background” has formed on the planet. The OCP concentrations in the Sea of Okhotsk and the Bering Sea can be considered a background level, while the Sea of Japan is exposed to contamination from countries using these substances in agriculture.

Three new photochromic spiropyrans containing a carboxylic group in the indoline fragment and an aldehyde substituent in the [2H]-chromene moiety were synthesized. The structure of the compounds obtained was studied using 1 H and 13 C NMR, IR and elemental analysis. Single crystal X-ray analysis was used to refine the molecular structure of 8′-formyl-1,3,3,6′-tetramethyl-spiro[indoline-2,2′-2H-chromene]-5-carboxylic acid. It was found out that in the solid state the molecules of that compound are arranged in dimeric associates due to the formation of intermolecular hydrogen bonds between carboxylic groups of two adjacent molecules. All the spiropyrans were shown to be photochromic with the lifetimes of the open forms in the range of 1.5–46.0 s.

A one-pot synthesis and structure study of a new salt spiropyran of the indoline series containing 2H-chromene vinyl-3H-indolium moiety as a substituent at the 8'-position are described. The structure was confirmed by 1H and 13C NMR and IR spectroscopy and high-resolution mass spectrometry. The single crystals of the compound were investigated by X-ray diffraction analysis. The structure was compared with the previously known isostructural analog.

The Seebeck coefficient S and electrical conductivity σ of bismuth-telluride-based alloys with substituents in the Bi and Te sublattices are studied at pressures up to 12 GPa at room temperature. It is shown that the electrical conductivity increases with pressure and, despite a decrease in the Seebeck coefficient, the power factor S2σ increases in p-Bi0.5Sb1.5Te3 and n-Bi2Te1.65Se0.65S0.7 alloys. A maximum increase in the power factor is observed for n-Bi2Te1.65Se0.65S0.7 in the pressure range of 3–4 GPa corresponding to the electronic topological phase transition. The studied alloys are used in modeling the thermoelectric module with adjustable mechanical stress applied to thermoelements.

Nanocomposite thermoelectrics based on Bi0.45Sb1.55Te2.985 solid solution of p-type conductivity are fabricated by the hot pressing of nanopowders of this solid solution with the addition of SiO2 microparticles. Investigations of the thermoelectric properties show that the thermoelectric power of the nanocomposites increases in a wide temperature range of 80–420 K, while the thermal conductivity considerably decreases at 80–320 K, which, despite a decrease in the electrical conductivity, leads to an increase in the thermoelectric efficiency in the nanostructured material without the SiO2 addition by almost 50% (at 300 K). When adding SiO2, the efficiency decreases. The initial thermoelectric fabricated without nanostructuring, in which the maximal thermoelectric figure of merit ZT = 1 at 390 K, is most efficient at temperatures above 350 K.

The energies of combustion of liquid dicyclopropyldinitromethane and liquid tricyclopropylmethane were determined by calorimetry of combustion at T = 298.15 K. The enthalpies of vaporization were estimated on the basis of electrostatic potential model. The formation enthalpies of the compounds in liquid and gas states were obtained from these data. The gas enthalpies of formation were also calculated by methods of the group additivity and isodesmic reactions. The obtained experimental and calculation values were compared.

In n-Bi2Te3 and n-Bi2Te3 –ySey thermoelectrics, the surface states of Dirac fermions of the interlayer Van der Waals surface (0001) are studied by scanning tunneling microscopy and spectroscopy. The surface morphology and modulated line profiles of the tunneling microscopy images are determined by local distortions of the surface density of electronic states and depend on the composition. The Dirac point ED in the studied compositions is localized in the band gap and shifts to the top of the valence band with increasing Se content in n-Bi2Te3 –ySey alloys. The dependence between the parameters of the surface states of Dirac fermions (Dirac-point position, Fermi velocity, surface fermion concentration) and thermoelectric properties (Seebeck coefficient and power parameter) in the thermoelectrics under study is determined.

The combustion energy of crystalline copper(II) pivalate was determined by static-bomb isoperibolic calorimetry. The standard enthalpy of formation was calculated on basis of obtained results. The value of standard enthalpy of formation was used to calculate the enthalpy of breaking bond Cu---Piv by the reaction: Cu(C5H9O2)2(cr) = Cu(cr) + 2C5H9O2·(g) and the enthalpy of formation of the trimer Cu3(Piv)6 in the gaseous state.

This article is an array of materials of own research of the responses of the human brain to radio frequency electromagnetic fields (EMF RF) of non-thermal intensity. The results of studies with the participation of volunteers presented a characterization of the response of the central nervous system to short-term exposures to EMF RF from the industrial generator and various cellular communication standards under conditions with predominantly irradiation of the head. There was given an estimation of the physiological significance of these effects and their dependence on human EEG typological features. The examination of persons working in conditions of chronic exposure of EMF RF, allowed present the dependence of neural effects on the work experience.

Concentration of organochlorine pesticides (OCPs) (α-, β-, γ- hexachlorocyclohexane (HCH), dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethane (DDD), dichlorodiphenyldichloroethylene (DDE)) in four species of Pacific salmon (pink, chum, chinook, and sockeye) are presented. OCPs in salmon organs increased in the following order: musclelivereggsmale gonads. Concentrations of the OCP in salmon organs increased in following order: DDE γ-HCH α-HCH. The level of pollutants in salmon is compared with the sanitary and epidemiological norms of Russia and other countries. Cancer and noncancer hazard ratios through consumption of salmon in Russian Far East for both men and women also were summarized. Noncancer and cancer hazard ratio values were far below threshold values (1.0).

Magnesium alloy Mg-1.0%Zn-0.3%Ca was processed by equal channel angular pressing (ECAP) with the aim to refine its microstructure. ECAP was found to reduce the average grain size from 106.0 ± 2.05 μm in the initial state to 4.0 ± 0.19 μm and 8.0 ± 0.18 μm in the transverse and longitudinal sections, respectively. This resulted in a slight strengthening (the yield strength and the ultimate tensile strength rose from 92 and 194 MPa in the initial stat to 106 and 215 MPa after processing, respectively). The main advantage of ECAP is the concurrent increase of tensile elongation from 12.8% to 23.9%. The absence of pronounced strengthening and a significant increase in ductility are associated with the formation of an inclined basal texture, along with activation of prismatic slip during ECAP. It was also shown that ECAP leads to an increase in the fatigue limit of the alloy from 100 MPa to 110 MPa and does not impair its resistance to chemical corrosion.

Relevance. Occupational activity of employees of EMERCOM of Russia in the Arctic region is associated with continuous operating response, physical and psycho-emotional stress, increased social and professional responsibility, and vital threat.Intention. To determine the level of self-actualization as a determinant of the professional development of EMERCOM of Russia employees with various professional experience in the conditions of the Arctic region.Methods. The study involved 226 men – employees of the EMERCOM of Russia, who were divided into 4 groups depending on their professional experience and region of residence. The level of self-actualization of the EMERCOM of Russia staff was assessed using the “Self-Actualization Test” (CAT), which is based on the personal orientation questionnaire by E. Shostrom.Results and Discussion. The results of the study showed that the EMERCOM of Russia employees with professional experience of up to 5 years in the Arctic region (1st group) have an average level of self-actualization; employees of the EMERCOM of Russia with professional experience of 5 to 10 years in the Arctic region (2nd group), with professional experience of over 10 years in the Arctic region (3rd group) and professional experience of over 10 years in Voronezh (4th group) have high level of self-actualization.Conclusion. According to the study results, self-actualization as a determinant of the professional development of EMERCOM of Russia employees in the 1st group is manifested as self-esteem, acceptance of aggression, synergy, spontaneity; in the 2nd group – value orientation, ideas about human nature, orientation in time, self-acceptance; in the 3rd group – support, cognitive needs, self-acceptance, sensitivity, contact, acceptance of aggression, self-esteem, flexibility of behavior, orientation in time; in the 4th group – creativity, ideas about human nature, flexibility of behavior, synergy, self-acceptance, contact, spontaneity, sensitivity, cognitive needs.

New indoline spiropyrans containing conjugated cationic fragments and bulky substituents in the 2H-chromene moiety were synthesized by a simple one-pot method. The structures of the obtained compounds were confirmed by 1H and 13C NMR (including 2D methods) and IR spectroscopy, as well as by element analysis and HRMS. Molecular structure of 1,3,3-trimethyl-6′-formyl-8′-benzyl-spiro[indoline-2,2′-2H-chromene] was refined by single crystal X-ray. A comparative analysis of the spectral and photochromic properties of salt spiropyrans and similar structures without a cationic fragment was carried out. It was found that the introduction of the cationic substituent at the 6′-position of the 2H-chromene moiety leads to a significant increase in the photoinduced isomer's lifetime.

Microstructure (including its uniformity), texture, and mechanical properties of Mg-Al-Zn-Mn alloy billets after radial-shear rolling (RSR) were investigated. RSR with the temperature in the interval 420–140 °C and true strain up to 2.63 was shown to lead to grain refinement down to 1.5–3.5 μm (as determined by optical microscopy). The microstructure was found to be reasonably uniform over the transversal cross-sections of the billets. The transmission electron microscopy analysis also revealed submicron sized grains and the formation of two types of particles: Mg17Al12 particles 300–500 nm in size and MgAl nanoparticles of different shapes 20–40 nm in size. Increments in strain and step-wise decrease in deformation temperature with the number of RSR passes was found to lead to a transformation of the initial basal texture to the prismatic texture. The RSR of the Mg-Al-Zn-Mn magnesium alloy was demonstrated to result in significant strength and good ductility owing to a fortunate interplay between fine grain structure and favorable texture promoting activity of non-basal slip systems.

Synthesis, structure study, and photochromic properties of new salt spiropyrans of indoline series containing chlorine and bromine atoms in the 6'-position of the 2H-chromene moiety have been reported. The structure of the obtained compounds has been confirmed by 1H NMR spectroscopy and X-ray diffraction analysis. The compounds are photochromic; the long-wavelength absorption maximum for photoinduced isomer shows a considerable hypsochromic shift, while the lifetime increases considerably as compared with the fluorine-containing analog.

—The study of the influence of different types of the surface treatment of medical stainless steel (12H18N10T) on the antibacterial effect has been carried out in this work. It is found that the steel samples that are treated by sandblasting with Al2O3 electrocorundum, electropolishing, and passivation have an antibacterial effect, as well as the thermally oxidized steel samples. The samples with passivation have antiglare properties.

The modern technology of heat-protective clothing is increasingly aimed at maintaining the active function of materials. Adding heat-preserving components into the volume of heat-insulating fibrous materials changes their structure and properties. In this article, the methods of forming the structure of multi-component insulants with heat-preserving components, as well as the study of structural and thermophysical properties, are presented. Composite textile materials were used in this study, namely a 0/30/50/100% Outlast textile (based on polyester fleece, 70%) + Termofiber (fiber-insulated polyester material, 100%). Based on the research, we established the structural parameters of Termofiber fibrous canvas and the Outlast textile. The study of the thermal conductivity of complex combined insulation materials was performed for different temperature conditions (up to +25 °C) and for the proportion of the heat-accumulating textile components. Based on the obtained research results for the development of complex materials from Termofiber + the Outlast textile, the fraction of the Outlast textile component should be limited to no more than 40% for textile shells in clothing that are operated at a temperature of +5 °C or below. Further conditions for determining the composition of the studied materials for clothing can be settled by taking into account the density of the materials, the mass, and the general thermal insulation of clothing.

The work provides a comprehensive analysis of efficient organization in the stock-raising industry when fed with high protein fodder. For that end, a dynamic analysis of volume and geographical indicators of soybean production, as well as ways to increase productivity, was initially conducted. The authors believe that biologically active preparations should be used for pre-treatment of seeds and foliar top dressing of plants. This will increase the yield by 2–3 dt/ha and the protein content by 3–4 %. The next step in the analytical procedures was conducting an experiment connected with introduction of soybean meal into the diet of young pigs. This will improve the physiological state of pigs and intensify their live weight gain.

The adsorption and protective properties of the corrosion inhibitors SolIng IK-2, IK-3, and IK-4(A) are studied by the method of electrochemical impedance spectroscopy. It is found that these inhibitors efficiently protect against corrosion in 1 M HCl solution. The calculated degrees of surface filling indicate a high adsorption capacity of the studied compounds, which strongly depends on their composition. SolIng IK-2 and IK-4(A) are the most effective compositions exhibiting a high degree of surface filling already at low concentrations (at concentrations up to 0.025 g/L θ = 0.6–0.98).

Cyclocondensation of gossypol, the pigment of Gossypium (cotton), and Fischer’s bases produced two new spirocyclic compounds with potentially combined pharmacological and photoswitching activities. The structures and photochemical properties of the synthesized compounds were studied using PMR, IR, and UV spectroscopy.

The effects of landscape heterogeneity on changes in the common shrew population were researched. Multiyear (1987–2017) time series data on species abundance in the plain and piedmont areas of the Pechora-Ilych State Nature Biosphere Reserve have been analyzed using the Fourier spectral analysis method. A cyclic component of three years and another one of lower value at five years were identified in the common shrew population dynamics in the piedmont area. In the plain area, changes in the animal population are more chaotic and periodic components are poorly manifested in the time series. The influence of landscape heterogeneity on the species population and its amplitude of fluctuation were also identified; these parameters are significant in the piedmont area and negligible on the plain.

A series of new spiropyrans of indoline series with ortho-hydroxyaldimine substituent has been synthesized, their structure and photochromic properties have been studied. The structure of the obtained compounds was confirmed by the data of 1H NMR and IR spectroscopy and elemental analysis. Photochromic properties of the prepared compounds have been studied. The introduction of ortho-hydroxy group into aldimine fragment of molecule (in the 6 position of the 2H-chromene fragment) has increased the lifetime of merocyanine isomer by 40 times as compared with amino-substituted spiropyran.

A new salt spiropyran of indoline series containing benzyl substituent in the 8'-position of the [2H]-chromene moiety of the molecule has been synthesized and studied. The structure of the obtained compound has been confirmed by methods 1H NMR and IR spectroscopy. The study of spectral characteristics and photochromic behavior of the target compound has shown that growing of its single crystal resulted in destruction on account of hydrolysis in acetonitrile. The 1H NMR spectra of the initial salt spiropyran and product of hydrolysis have been compared.

The energy of combustion of a pure sample diphenyl oxide in crystal and liquid states at T = 298.15 K was determined by isoperibolic calorimeter combustion. The enthalpy of fusion, the triple-point temperature and the purity of the sample were estimated by studying the melting process by calorimetric method. The enthalpies of formation in the crystalline, liquid and gaseous states were calculated. All results are compared with the experimental values reported in the literature. The value of gas-phase enthalpy of formation was calculated by G4 method in combination with isodesmic reactions. The results of this calculation are in good agreement with the obtained experimental value.

The structures of small silver clusters (Ag2, Ag3, Ag13) and their interaction with ligands of the cholesterol series, namely, cholesterol (Ch) and thiocholesterol (TCh), are calculated by the density functional theory (DFT) methods and the second-order Moller–Plesset perturbation theory (MP2). Trends in the geometric structure and interaction energy of the silver–cholesterol ligand cluster are estimated depending on the size of the metal cluster and the replacement of cholesterol by the sulfur-containing analogue. For Ch–Ag13 and TCh–Ag13 systems, the geometric structure of the metallic subsystem is a slightly distorted icosahedron with the Ag–Ag bond length ranged 2.8–3.0 A. Cholesterol is coordinated to the icosahedral facet so that the shortest Ag–O distances range from 2.3 to 2.4 A. In the case of thiocholesterol, a configuration in which the ligand is coordinated by the edge of the icosahedron with two approximately equal distances of Ag–S (2.537 and 2.547 A) is preferable.

Controlled purification of non-aqueous solution of CdSe/CdS/ZnS quantum dots (QD) (dispersed in toluene or chloroform) from an excess of surfactant (oleic acid) was studied. The separation of unbound oleic acid from QD solution was carried out by using high-density polyethylene (HDPE) membrane. The secondary solution with a separated surfactant as well as initial QD solution was spread over the water surface to obtain a monolayer with its compression isotherms studied using Langmuir-Blodgett (LB) technique. This approach allowed us to determine the concentration of surfactant at a level of 10−5 mol/l or less for CdSe/CdS/ZnS QD. For better understanding of the influence of purification on the properties of QD, the monolayer of QD was transferred onto solid substrate and its morphology was studied. Atomic force microscopy showed that removal of oleic acid excess results in a more uniform and dense packing of quantum dots.

Based on a new polyfunctional derivative of dihydroxyisophtalic aldehyde (1) spiropyrans of 1,3-benzoxazin-4-one series with two carbonyl and a hydroxygroup in the [2H]-chromene fragment were synthesized. The results of single crystal X-ray analysis of 6′-carbomethoxy-3,5-dimethyl-8′-formyl-5′-hydroxy-4-oxospiro[1,3-benzoxazine-2,2′-chromene] (7a) helped to establish that condensation of 1,3-benzoxazine-4-onium perchlorates with (1) leading to the formation of spiropyrans occurs on the formyl group located at the position 3 of the starting aldehyde. The obtained spropyrans demonstrate photochromic activity at room temperature. Introduction of an electron donating methoxy group into the heteroarene part of the spiropyran molecule enhances its photocolorability.

The structure and photochromic transformations of composite organometallic nanosystems composed of Ag nanoparticles covered with a layer of indoline-spiropyran (ISP) molecules from solutions were studied by spectrophotometry, surface Raman scattering spectroscopy (SERS) and quantum chemistry. Analysis of experimental data showed that studied nanostructured systems have photochromic properties, manifested in the reversible photo-induced changes both of the electronic-absorption spectra and of the relative intensity of the SERS bands. The open form of ISP, formed in the organometallic nanostructured film as a result of photochromic transformations, has an adsorption geometry, and, possibly, a conformation different from that formed as a result of chemisorption of ISP molecules on silver colloids.

Synthesis, study of structure and photochromic properties of new salt spiropyran of indoline series containing a fluorine substituent in the 6′-position of the 2H-chromene moiety have been described in the work. The structure of the compound has been confirmed by 1H NMR spectroscopy and X-ray diffraction analysis. Comparison of the structure of the compound with the previously studied analogue containing a methyl group instead of a fluorine atom in the 6′-position of the [2H]-chromene moiety has been made. This compound has been found to be photochromic, long-wavelength absorption maximum of its open form shows a bathochromic shift, and lifetime is increased three times as compared with the methyl analogue.

New spiropyran salts in the row of 1,3,3-trimethylspiro-indoline-2,2'-[2Н]-chromene are prepared and their structures are investigated. Molecular structures of obtained compounds are confirmed by X-ray diffraction and NMR spectroscopy. An open merocyanine isomer is found to be the most stable structure for one of these compounds.

The parameters of barotropic and baroclinic oscillations in the subinertial range have been obtained by numerical simulations of the Black Sea circulation using a model developed at the Marchuk Institute of Numerical Mathematics, Russian Academy of Sciences. The structures and periods of barotropic and baroclinic seiches are in good agreement with the known theoretical predictions and results of numerical modeling of seiches obtained for the Black Sea subbasins.

Samples of the topological insulator n-Bi2Te3 (0001) have been studied in air by means of atomic force microscopy. The possibility to increase the sample conductivity by five or more orders of magn...

Biocompatibility of magnesium alloy WE43 was investigated under in vitro and in vivo conditions. The biodegradation of WE43 samples in vitro was found to occur very rapidly. The evolution of a significant amount of hydrogen as a product of biodegradation prevented the attachment of cells to the sample surface and caused their likely damage. A tendency to the lysis of red blood cells and a drop in the index of survival of mesenchymal stromal cells were observed. By contrast, in vivo, after subcutaneous implantation to mice, the biodegradation rate of WE43 was significantly lower and no sizeable hydrogen generation occurred. An intimate contact between the sample surface and the surrounding tissue was formed without damage to the tissue, with the occurrence of neoangiogenesis in the contact area. Importantly, morphological studies showed that no major detrimental systemic effects were associated with the implantation of WE43 in mice.

Mercury (Hg) accumulation in fishes is a serious threat for food security because mercury induces dieseases. Here we studied the total mercury content in four species of Pacific salmon (pink, chum, sockeye and chinook), caught in the Sea of Okhotsk, the Bering Sea, and the Kuril oceanic waters. Results show that the lowest concentration of mercury was found in the pink salmon, and the highest was 5–6 times higher in sockeye. Hg concentrations exceed several times those in other species of Pacific salmon from the North Pacific

Standard molar enthalpy of formation in the solid state at T = 298.15 K of l -threonine was derived from energy of combustion determined by static bomb combustion calorimetry. Heat capacity of l -threonine was measured by vacuum adiabatic calorimetry over the temperature range (7.37–371.97) K. Heat capacities and main thermodynamic functions in solid state were tabulated as a function of temperature from 5 K to 370 K. The entropy of formation and Gibbs energy of formation at T = 298.15 K of l -threonine in the condensed state were computed on the basis of the experimental results obtained. All results are compared with experimental values reported in the literature.

Current neural network approaches mostly consider the synaptic signal transfer as a basis of interneuronal communication. At the same time, extrasynaptic signaling plays important role in the animal behavior. In the paper processes of information distortion during the extrasynaptic mixing are studied using braid theory. An approach to the procedural generation of deep neural networks incorporating properties of extrasynaptic information dynamics is proposed.

The energies of combustion of crystalline 1-methyl-2,3,3-triphenylcyclopropene (C22H18), methyl2,3-diphenylcycloprop-2-ene-1-carboxylate (C17H14O2) and 1,2,3-triphenylcyclopropene (C21H16), were determined in isoperibolic calorimeter at T = 298.15 K. The enthalpies of sublimation were measured by isothermal heat-conducting differential microcalorimeter (“Setaram”) at T = 298.15 K. The enthalpies of formation in the crystalline and gaseous states were calculated. The values of enthalpies of three group contributions: [C-(Cd)2(Cb)2], [C-(Cd)2(CO)(H)] and [C-(Cd)2(Cb)(H)], which absents in the Cohen additive scheme, were estimated.

The heat capacity of 2-methylfuran in the temperature range of 8–350 K was determined by vacuum adiabatic calorimetry. The temperature, the enthalpy and the entropy of fusion and purity of investigated sample were determined by fractional melting. The smoothed thermodynamic functions (changes in enthalpy, entropy and Gibbs energy) in the region of 8–350 K were calculated. The entropies of formation and Gibbs energies of formation of 2-methylfuran at 298.15 K in the liquid and ideal gas states were found, using the literature data.

The new spiropyran systems with an azomethine bridge were synthesized from a spiropyran containing aminogroup at 6′ position of the benzopyran fragment and substituted aromatic aldehydes. The chemical structure of compounds is confirmed by elemental analysis data, NMR (1H and 13C) and IR spectroscopy. Photochemical studies revealed the presence of photochromic properties at room temperature for one of the obtained spiropyrans.

The Black Sea shelf is a region of intense manifestation of various dynamical processes. Under the influence of different natural forces, eddy-wave phenomena develop here, which influence the general circulation of sea waters, biological productivity, and the condition of the engineering structures. Modern numerical models allow us to simulate and analyze the processes of the joint dynamics of marine circulation and large-scale waves. In this work, we study the spatiotemporal spectral characteristics of the sea level and velocity fluctuations formed due to atmospheric forcing and tidal potential. The hydrophysical fields are calculated using the Institute of Numerical Mathematics, Russian Academy of Sciences (INM RAS), σ model based on primitive equations. We use the CORE data as atmospheric forcing at the sea surface; the tidal potential is described by the semidiurnal lunar constituent M2. Analyzing the simulation results makes it possible to emphasize that accounting for the semidiurnal tidal potential not only improves the accuracy of the sea-level calculation at coastal stations, but also generates subinertial baroclinic oscillations previously found in the Black Sea from the data of in situ observations.

Iron and iron–cobalt nanostructures are probed by means of Mossbauer spectroscopy combined with scanning electron microscopy, energy-dispersion analysis, and X-ray diffraction. The obtained nanostructures are single-phase Fe1 − xCo x (0 ≤ x ≤ 1) nanotubes that have high degrees of polycrystallinity and a bcc lattice 12 μm long and 110 ± 3 nm in diameter, with walls 21 ± 2 nm thick. A random distribution of the orientations of the magnetic momenta of Fe atoms are observed for Fe nanotubes, while Fe–Co nanotubes are characterized by a magnetic texture along their axes.