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Main pipelines as long linear objects are vulnerable to dangerous natural and man-made influences. One of the technogenic sources is large-scale explosions, which cause a sharp fluctuations of soil and cause serious damage to underground pipelines. When calculating the strength of pipeline systems, it is assumed that the damage occurs mainly due to additional axial stretching. However, the destruction and damage of pipelines can occur during seismic impacts directed perpendicular to the longitudinal axis of the pipeline. To assess the impact of longitudinal and transverse waves on the underground pipeline during seismic action a software-calculation module is developed. It implements a model of dynamic strength analysis, which allows estimating the magnitude of longitudinal and trans-verse seismic loads on the underground pipeline to establish safe parameters of seismic loads and geometric dimensions of the protected object. The final system of equations of motion of N nodes of a discrete system for a single length of the pipeline is presented as a system of 4N equations of the first order. The efforts on the internal nodes are determined by the strain stresses at the displacement of the nodes of the adjacent rods. The efforts on the nodes of the pipe contour are the diffraction interaction of seismic waves in the soil with the pipe. The system of equations is supplemented by the corresponding initial and boundary conditions. The dependences of the inflow of longitudinal and transverse pressure of explosive seismic pressure on the pipeline are established. The dependences of stresses in the pipeline of the diameter, thickness and type of soil are researched.

The article presents the results of a comparative evaluation of five promising hybrids of Chaenomeles japonica (Thunb.) Lindl. ex Spach (2-44-05, 3-27-05, 5-50-03, 1-64-05, 3-17-05), identified according to a complex of commercially valuable traits (winter hardiness, yield, fruit weight, low thorniness, resistance to fruit rot), and Likhtar variety in the conditions of Belarus. Significant differences have been found in terms of the amount of substances accumulated in fruits. The samples were characterized by low and very low levels of solids and sugars in combination with high acidity, with the exception of the Likhtar variety and hybrid 3-17-05, that show an average level, as well as a very low content of ascorbic acid. Hybrid 3-17-05 has been singled out according to a set of 6 indicators (solids, soluble solids, sugars, titrate acidity, sugaracid ratio, phenolic compounds); hybrid 3-27-055 – according to a set of 5 indicators (solids, soluble solids, sugars, ascorbic acid, phenolic compounds). Hybrids 3-27-05 and 5-50-03 were the best in terms of the complex of biologically active substances (ascorbic acid, pectin and phenolic compounds).

The article presents the results of studies to determine the compatibility of scion-rootstock combinations of apricot and peach at the stage of growing planting material in the nursery fields by using different methods. When growing planting material of apricot and peach in the field, three forms of incompatibility are determined to exist: localized disease, starvation of the root system, weak cohesion between the scion and rootstock. Initially during laboratory based testing the content of RNA and DNA was determined (using the “ArtRNA MiniSpin” reagent kit) as well as their ratio for 3 clonal rootstocks and 18 scion-rootstock combinations of apricot and peach, on the basis of which the compatibility coefficients were calculated, which made it possible to distinguish three groups: good compatibility (K = 0.01–0.17); medium compatibility (K = 0.18–0.20) and poor compatibility (K > 0.20), coinciding with groups according to the results of agrobiological evaluation in the field. Apricot varieties Znakhodka and Pamyat Loiko, incompatible with the stock VPK-1, were established.

New synthesis of 4-trifluoromethyl-2H-chromenes via the reaction of 2-(trifluoroacetyl)phenols with vinyltriphenylphosphonium chloride provides a reliable and prompt access to various substituted at the benzene ring 4-trifluoromethyl-2H-chromenes.

The present paper provides the ways of implementing methods of fuzzy set approach, which contributes to an increase in the accuracy, efficiency and functional flexibility of the complex control and recognition monitoring systems for the environmental and geoengineering system simulation. They are based on data mining methods and may be implemented with the help of intellectual technologies, including the combination of model pluralism, membership functions, methods of nearest neighbour, results of fractal and chaos theories, methods of ensuring robustness and retrospective analysis of the decision tree for success in decision making in similar situations. It is proposed to use the model pluralism to explain a particular information process, which uses a number of adequate models, describing the behavior of objects in the case where each of the model reflects its behavior objectively, but under different circumstances, which are difficult to consider a priori in real time when choosing an adequate model. It is shown that the method of the nearest neighbour should be used if it necessary to identify causal relationships and predict further development of the environmental safety events.

The convenient and scalable preparative approach for the two-step α-methylation of ketones is described. The optimized protocols for regioselective preparation of enaminones with further diastereoselective and functional groups tolerant hydrogenation to α-methylketones are developed. The scope and limitations of the proposed methodology are discussed. The advantages compared to known procedures are demonstrated. The unexpected role of acetone in the hydrogenation is suggested. The evaluation of the method for both early building block synthesis and late-stage CH-functionalization is shown. The elaborate procedures' preparability and scalability are demonstrated by the synthesis of several α-methyl ketones up to 100 g amount.

A number of 2-substituted 4–7-membered cyclic amino acid esters bearing endocyclic amino group were sequentially mesylated and cyclized via the CSIC reaction strategy to give the key precursors 3a-substituted bicyclic isothiazolidin-4-one 1,1-dioxides. Further reaction with methyl (triphenylphosphoranylidene) acetate afforded the corresponding 3a-substituted 2-[(triphenylphosphonio)acetyl]-perhydro[1,2]thiazoloazahetaryl-3-olate 1,1-dioxides. The nature of the substituent at position 3a plays a crucial role in the reaction direction with this Wittig reagent. Specifically, 3a-unsubstituted counterpart participates in the classical course of the reaction providing the expected prototropic mixture of corresponding esters.

Recent numerical calculation of the coefficients of diffusion of radiation point defects in hexagonal crystals have shown that the main assumption of the theory of radiation growth of zirconium—namely, the assumption about diffusional anisotropy difference (DAD)—is not fulfilled. Thus, the elastic ideology based on the concept of bias of sinks, i.e., elastic interaction difference (EID), remains relevant. In this connection, bias for the basal edge loop of zirconium in a toroidal reservoir is numerically calculated by the finite difference method under consideration of the elastic anisotropy of a hexagonal crystal. The toroidal geometry of the reservoir allows one to perform calculations for a loop with any size and without any correction for the elastic field in the region, in which it has an effect. The dependences of the bias of the loop on its radius and nature are obtained for various drain densities. The essential role of the shape of the boundary condition on the external surface of the reservoir is shown. Prospects for further research in constructing the theory of radiation growth of zirconium on the basis of elastic ideology are outlined.

The present work is devoted to the study of the reactivity of tetrahydropyrrolo[1,2-b]isothiazol-3(2H)-one 1,1-dioxide framework. This scaffold possesses two reaction centers: the EWG-activated methylene group and the carbonyl functionality, which are the basic variation points. At the same time, the attached 3a-substituent had a significant impact on the course of the explored reactions and its role was also investigated. In this regard, the corresponding 3a-unsubstituted and 3a-methylated tetrahydropyrrolo[1,2-b]isothiazol-3(2H)-one 1,1-dioxides were chosen as model substances involved in chemical properties evaluation. With a view to pre-assess the activity of the model compounds, a deuteration study was conducted. Furthermore, the interaction with a variety of electrophilic and nucleophilic agents was explored. The most striking difference in the chemical behavior was observed in the reaction with the Wittig reagent triphenylcarbethoxymethylenephosphorane (Ph3P=CHCO2Me). In particular, unlike the 3a-unsubstituted substrate, the 3a-methylated one gave the unusual phosphonium betaine, namely 3a-methyl-2-[2-(triphenylphosphonio)acetyl]-3a,4,5,6-tetrahydropyrrolo[1,2-b]isothiazol-3-olate 1,1-dioxide. The proposed mechanistic insights of this reaction have been discovered.

A series of 2,2-disubstituted 8-azachromanones, including spirocyclic compounds, have been synthesized via Horner–Wadsworth– Emmons reaction. Dimethyl methylphosphonate was acylated with methyl 2-methoxypyridine-3-carboxylate to afford the key intermediate – dimethyl [2-(2-methoxypyridin-3-yl)-2-oxoethyl]phosphonate. Further reaction of this phosphonate and ketones followed by treatment with TMSCl–NaI provided the target 8-azachromanones. Scope and limitations of the developed synthetic method have been investigated.

An approach to di- and trihetera[3.3.n]propellanes (n = 2–4 ), advanced morpholine and piperazine analogues, is developed. The key step of the reaction sequence included a [3 + 2] cycloaddition rea...

The present paper provides the methodology of monitoring and evaluation of dynamics of radioactive contamination from radioactive waste depositories, which supposes the wide application of the fuzzy set theory results, heuristics and risk-oriented management. The developed technique is based on hybrid modelling and data mining principle and provides effective control operations, realises appropriate environmental monitoring, assures trustworthy of decision making in situations of noise, ambiguity and misrepresented data.

The present paper provides the modelling of the explosion of the charges of the traditional (trotyl) and new blended explosive substances: polymix GR1/8 (74 %) + KRUK2 (26 %), compolite GS6, polymix GR4-T10. As a result of the research, it has been established that when using TNT a specific impulse is formed, which is by 40 % more than an explosion of new mixed explosives, and the safe distance from the source of the explosion of such explosives is increased by 25 %–50 %. On the basis of the established dependences of excess pressure, the specific impulse on the type and mass of charge, as well as the distance from the epicenter of the explosion, an engineering method has been developed for calculating dangerous parameters of the explosion impact on the environment.

The present paper provides a simple mathematical model that describes the synergistic interaction of environmental factors that occur in urban ecosystem. The model predicts the value of maximum synergistic action and the condition for its achievement, as well as implies the dependence of synergistic action on the intensity of the agents used and the proportion of irreversible damages after the combined effects. The developed mathematical model can be used to predict the accumulation of pollution in the ground layer of soil.

The present paper provides numerical simulation of interaction of wave processes in the system “soil massif – underground pipeline” in explosion of charge on the surface of ground. Construction is considered in the framework of nonlinear theory of shells of Tymoshenko type. Soil is modelled by a solid porous multicomponent visco-plastic medium. The study establishes patterns of changes in stress-strain state of system depending on depth of pipeline laying and its diameter.

Systems of anaerobic digestion should be used for processing of organic waste. Managing the process of anaerobic recycling of organic waste requires reliable predicting of biogas production. Development of mathematical model of process of organic waste digestion allows determining the rate of biogas output at the two-stage process of anaerobic digestion considering the first stage. Verification of Konto’s model, based on the studied anaerobic processing of organic waste, is implemented. The dependencies of biogas output and its rate from time are set and may be used to predict the process of anaerobic processing of organic waste.

The Green’s function method for hexagonal crystals within the Lifshitz–Rosenzweig (1947) and Kroner (1953) approaches has been used to obtain analytical expressions for the energy of elastic interaction of radiation-induced point defects with dislocation loops of three types: the basal edge dislocation loop (cloop), the basal shear dislocation loop, and the edge a-loop (bedding plane {11 20}, Burgers vector b D = 1/3〈11 20〉). In the case of the basal edge dislocation loop, a similar expression has been obtained independently by solving the equilibrium equations using the Elliott method. A numerical comparison of the derived expressions for zirconium has demonstrated a complete identity of the results obtained within the approaches considered in this study.

An approach to 3-oxa-7-azabicyclo[3.3.0]octanes, bicyclic morpholine analogues, is reported, which relies on [3+2] cycloaddition of maleic anhydrides or furan-2(5H)-ones and an in situ generated azomethine ylide. The utility of the method was demonstrated on a multigram scale.

A series of pentaalkoxychlorocyclotriphosphazenes was synthesized. The spectral characteristics of the synthesized compounds (31Р, 1H, 13С NMR) were studied. It was shown that the complexity of the NMR spectra of pentaalkoxychlorocyclotriphosphazenes is associated with the magnetic nonequivalence of the phosphorus atoms in the triphosphazene cycle and the hydrogen and carbon atoms in the alkoxy groups on these phosphorus atoms, as well as the cis/trans isomerism of the latter groups.

Introduction: Application of lactic acid bacteria for synthesis of silver (AG) nanoparticles (NPs) could be a good ecological friendly alternative to chemical and physical methods. The objective of this study was to investigate the biosynthesis of silver NPs using Lactobacillus strains and to compare their monosaccharide composition of capsular exopolysaccharides and the antibacterial activity of synthesized nanoparticles. Methods: The washed cells of 22 Lactobacillus strains were used for in vitro silver nanoparticle biosynthesis from silver nitrate solution. The NPs formation was confirmed by UV-visible spectroscopy and transmission electron microscopy (TEM) analysis. TEM micrographs were used for the evaluation of NPs size. The monosaccharide composition of capsular exopolysaccharides was determined using GC/MS analysis. The antimicrobial activity was determined by agar well diffusion assay. Results: The capsular layers of Lactobacillus strains contained heteropolysaccharides that were composed mostly of glucose, mannose, galactose and rhamnose in a different molar ratio. It was found that Ag NPs with large size (30.65 ± 5.81 nm) obtained from L. acidophilus 58p were more active against S. epidermidis, E. coli, K. pneumonia, S. flexneri and S. sonnei compared with Ag NPs from L. plantarum 92T (19.92 ± 3.4 nm). Conclusion: The size and antibacterial activities of Ag NPs were strain-dependent and such characteristics may be due to the capsular biopolymer composition of Lactobacillus strains used for Ag NPs synthesis.

An approach to di- and trihetera[3.3.

Summary It is proposed to use the seismic data of the DSS on the territory of Ukraine to build neural network models of the seismic signal arrival times field, which allows the construction of longitudinal wave hodographs along arbitrarily oriented profiles in regions where do not have seismic observations. Also this possible use to correct the velocity section using one from methods of the inversion of hodograph. A comparison is made of simulated arrival times of longitudinal waves with those that were recorded on the territory of Ukraine. Parallels have been made between the modeling of the time field from meridional and latitudinal sources with the propagation of stresses, which external indenters create on the territory of Ukraine. At the same time, regional fault zones were reflected in the residuals of the time field. This shows that the artificial field of time, modeled by the neural network, is reflected in the real tectonic division of the territory of Ukraine.

The present paper provides the concept of self-renewing of ecosystems. It is shown that multidimensionality and mutual exclusion of individual components of the environment make the problem of optimization, i.e. achieving the conditions of sustainable development, too difficult. However, the goal of sustainable nature management is possible with the existence of ecosystem properties for self-renewal due to the presence of cyclical processes, ecological capacity, migration capabilities of ecosystem components and pollutants metabolism, as well as the use of waste-free and energy-saving technologies. It is proposed to model the ecosystem in the form of the “eight”, which reflects it as a closed cyclic system able for adaptation. When analyzing such a complex system, the following principles should be followed: simplification; consideration of processes in dynamics; considering the possibility of ambiguity, incompleteness and inaccuracy of information; using a risk-based approach to impact assessment; understanding the system as a hierarchical structure able for adaptation and development. It is noted that all local ecosystems in the region are interconnected and affect the characteristics of neighboring local ecosystems, usually requiring the adjustment of resources and connections.

The universal expressions have been obtained for components of the tensor Green’s function of an elastically anisotropic hexagonal medium. In contrast to the classical expressions (the Lifshitz–Rosenzweig method), they do not contain uncertainties of the type 0/0 upon the transition to the isotropic approximation and hold true for any hexagonal crystal. As an example of their use, the displacement and strain fields created by an edge dislocation loop lying in the basal plane of the crystal have been calculated.

Polyphasic taxonomic analysis was carried out for Bacillus sp. strain C6, as the antagonist of phytopathogenic bacteria and micromycetes. The combination of cultural, morphological, physiological, and biochemical properties of the strain has enabled researchers to refer it to the Bacillus subtilis group. It has been shown that the fatty acids of the strain’s cell walls were predominantly represented by branched iso- and anteiso-C15:0 and C17:0 fatty acids (over 85%), which was typical for the Bacillus amyloliquefaciens species. The molecular genetic analysis carried out on the nucleotide sequence of the 16S rRNA gene, and the profiling of polymorphic nucleotides have enabled researchers to refer the strain in question to Bacillus amyloliquefaciens subsp. plantarum.

Investigated are changes in the composition of paraffin-naphthenic hydrocarbons (PNH) in purifying water by the preparation Ekolan-M of crude oil. The main components of PNH are n-alkanes C9–C30 and iso-alkanes C8–C17. The absence in the purified water of iso-alkanes C9 and the presence in it of a small amount of n-alkanes C22–C26, whose concentration decreased compared with the initial one by 150–234 times is an evidence of nearly complete utilization by microorganism of the preparation of these fractions of hydrocarbons.

Chlorotrimethylsilane-promoted Biginelli-type reaction of benzaldehyde, acetoacetic acid derivatives, and various carboxyl-containing ureas was explored. It was found that the steric load of the urea substituents influenced strongly the reaction outcome; in particular, the method was efficient only in the case of unbranched mono-substituted ureas bearing either aliphatic or aromatic groups. The method allows performing a one-pot, protecting group free synthesis of dihydropyrimidines possessing carboxylic functionality.

Expressions for components of the Green’s tensor of the basic equation of the elasticity theory for hexagonal system crystals have been obtained using the Lifshitz-Rozentsveig method. A problem is in principle reduced to finding the roots of a sixth-order algebraic equation. They are either complex or purely imaginary for all known hcp metals. In both cases, the desired components of the Green’s tensor are calculated exactly in contrast to metals of the cubic system. A limiting transition to the isotropic approximation is shown.

The effect exerted by an electron beam with an energy of 0.5 MeV on the deformation of polycrystalline aluminum (99.5%) and copper (99.5%) under uniaxial tension at a rate of 2 × 10−4 s−1 in the temperature range from 40 to 100°C has been investigated. It has been established that the plasticity of the metal increases under irradiation with an electron beam: the level of the flow stress and the strain hardening coefficient in the irradiated state decrease, whereas the total resource of plasticity of the material increases. A mechanism of an increase in the plasticity of metals has been proposed. This mechanism is based on the radiation-induced generation of nonlinear strongly localized excitations of the crystal lattice, namely, discrete breathers, whose lifetime is significantly longer than the relaxation time of phonons. The interaction of discrete breathers with dislocations can stimulate the detachment of dislocations from stoppers and, consequently, an increase in the plasticity of the material.

It was studied the effect of Acholeplasma laidlawii var. granulum str. 118 to fatty acid composition of sugar beet calluses. It was established that acting of acholeplasma results to changes in the quantitative content of the individual fatty acids and in the qualitative composition of fatty acids in the lipids of calluses. The changing of the fatty acid composition of calluses lipids of sugar beet infected by A. laidlawii vargranulum str. 118 is observed as nonspecific response to biotic stress.

Application of DSS data of seismic studies in Ukraine to build models of neural network for time arrival field of seismic signals that allow to construct hodographs of longitudinal waves along arbitrarily oriented sections in regions that do not have seismic observations or to adjust velocity section applying one of the methods of hodograph inversion has been proposed. Comparison of the simulated time of longitudinal wave arrival with those ones that were registered in Ukraine has been made.

Using the Lifshitz-Rozentsveig method, an improved expression for the Green tensor in the case of a weakly anisotropic cubic crystal has been derived. It contains a number of additional terms disregard previously. An expression for the energy of elastic interaction of a point defect with a gas-filled pore, which differs from its analogue (commonly used referring to Eshelby) by an additional factor in the radial part, has been derived. In the case of weak interaction (in comparison with thermal energy), a correction to the efficiency of point defect absorption by a gas-filled pore is obtained, which appears quadratic in the anisotropy parameter and negative. As a result, the pore exhibits preference for absorption of vacancies in comparison with absorption of interstitials.

The phenotypic, chemotaxonomic and genetic peculiarities of 5 deep strains of Alteromonas macleodii (isolated from Adriatic and Ionian Sea water from a depth of 1,000-3,500 m) and 5 strains of the same species isolated from the surface layer of Aegean, Andaman, Black Sea and Atlantic Ocean water near the British shore have been studied. Electron microscopy has shown that the deep strains' cells were, on average, two times longer (2.1±0.2×0.7±0.1 µm) than the surface strains' (1.1±0.1×0.6±0.1 µm). Using fatty acid analysis (particularly the mono-unsaturated C16:1 and C18:1 fatty acids contents) the deep and surface isolates were clearly separated into two clusters. Distinctions between them were also found in different lectin binding capacity, which is probably determined by the structure of their extracellular polysaccharide matrix. Analysis of the results of PCR with primers to repeated nucleotide sequences revealed a higher level of genetic polymorphism in surface strains in comparison with the deep isolates. This division was confirmed by the cluster analysis method though it was not as clear as in the fatty acids analysis. The described peculiarities are probably reflective of specific conditions in which A. macleodii strains live on the surface or in the depth of the world's oceans.

The kinetics of decomposition of a supercooled melt or a viscous fluid under heat-insulating conditions during intensive nucleation has been investigated. Particles of a new phase have been studied, whose size is larger than the critical value, and for which the times are longer than the settling time of the classical quasi-steady state, which is characteristic of subcritical nuclei. The heat removal from the phase boundary is assumed to be the key process in the vicinity of a growing particle. The estimates of the duration of the stage of intensive nucleation, the maximum number of nucleated particles, and their average “size” have been obtained. Numerical simulations have been performed for nickel.

The initial stage of decomposition of a supercooled melt or a viscous liquid under heat-insulating conditions has been considered in terms of the method of virtual media. The heat removal from the interface is taken as the controlling process in the vicinity of a growing nucleus. In addition to the quasi-steady-state equations (which already became standard) for the nucleation rate and the distribution function of subcritical particles of a new phase, an estimating equation has been derived for the time required to reach steady-state values of these characteristics. Numerical evaluations have been performed for nickel. It has been demonstrated that the chosen model of the controlling process is valid only under the condition of weak heat removal. Attention has been drawn to the difference between the “diffusion” and “thermal” processes of nucleation.

Chlorotrimethylsilane-promoted Biginelli-type reaction of ethyl 2,4-dioxo-4-phenylbutanoate, benzaldehyde, and various (thio)ureas is explored. The outcome of the reaction depends on the structure of the (thio)urea used and is strongly affected by the acceptor electronic properties of the COOEt substituent in the molecule of the starting β-dicarbonyl compound. The di- and tetrahydropyrimidine derivatives obtained possess two functional groups with orthogonal reactivity, and thus represent promising building blocks for drug discovery.

N-Carbamoylamino acids were obtained through the alkylation of monosubstituted parabanic acids followed by hydrolysis of the intermediate products. This new methodology furnishes structurally and functionally diverse N-carbamoylamino acids in high preparative yields and excellent purity.

Trifluoromethyl-1,3-diones were investigated as reactants in the Biginelli reaction promoted by Me 3 SiCl. The dependence of the reaction pathway on the nature of substituent at the α-position to the carbonyl group was established. A set of new CF 3 -containing dihydropyrimidine(thi)one derivatives was obtained. A number of novel 5-CF 3 CO dihydropyrimidine(thi)ones were synthesized.

The lipopolysaccharide (LPS) from a new Enterobacteriaceae species, Rahnella aquatilis 2-95, was isolated and investigated. The structural components of the LPS molecule, namely, lipid A, core oligosaccharide, and O-specific polysaccharide, were obtained by mild acid hydrolysis. In lipid A, 3-oxytetradecanoic and tetradecanoic acids were found to be the predominant fatty acids. The major monosaccharides of the core oligosaccharide were galactose, arabinose, fucose, rhamnose, and an unidentified component. The O-specific polysaccharide was found to be assembled of a repeated trisaccharide unit of the following structure: Open image in new window The R. aquatilis 2-95 LPS is less toxic and more pyrogenic than the LPS from the R. aquatilis 1-95 strain studied earlier. Both acyl and phosphate groups are essential for toxic and pyrogenic activity of R. aquatilis 2-95 LPS.

The chlorotrimethylsilane-promoted Biginelli type reactions of aldehydes, thiourea, and cyanoketones led to a diverse set of tetrahydropyrimidine-2(1H)-thiones. Under similar conditions, thioureas, benzaldehyde, and cyanoacetamide reacted to give first representatives of hexahydro-5H-pyrimido[5,4-e][1,3]thiazin-5-ones in high preparative yield.

A simple and cost-effective one-pot parallel synthesis approach to sulfides, sulfoxides, and sulfones from thiourea was elaborated. The method combines two procedures optimized to the parallel synthesis conditions: alkylation of thiourea with alkyl chlorides and mono or full oxidation of in situ generated sulfides with H2O2 or H2O2–(NH4)2MoO4. The experimental set up required commonly used lab equipment: conventional oven and ultrasonic bath; the work up includes filtration or extraction with chloroform. The method was evaluated on an 81 member library of drug-like sulfides, sulfoxides, and sulfones yielding the compounds on a 30–300 mg scale. A small-scale synthesis of 2-(benzhydrylsulfinyl)acetamide (modafinil) utilizing our approach resulted in similar efficiency to the published procedures.