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A new approach has been proposed to study the dynamics of crystal structure deformations under external influences using the X-ray rocking curve imaging technique. Using this approach, the spatial distribution, type, and magnitude of deformations of the crystal structure of a langasite crystal, which is promising for industrial application, exposed to the ultrasonic irradiation (excitation of a standing ultrasonic wave) have been studied. [ABSTRACT FROM AUTHOR]

A grid-characteristic numerical method based on tetrahedron grids is applied to simulate wave processes in a composite material under the action of a pulsed shock load. An approach is proposed to increase the approximation order of the method on an unstructured grid in the three-dimensional case. Computational results for load pulse propagation in a three-layer composite are presented. [ABSTRACT FROM AUTHOR]

Regular measurements of radio emission produced by relativistic air shower particles were started at the Yakutsk array in 1986. After monitoring of the background noise in the array area, the frequency of 30–35 MHz was chosen, because noise level is minimal in this frequency range. During this time, air showers with highest energies of 100 EeV were registered. By means of hybrid measurements of charged particles, Cherenkov light and radio emission, it was shown that signal amplitude proportional to air shower energy and shape of lateral distribution at sea level correlates with the depth of maximum development. By these characteristics, the atomic weight of primary particles that generated air shower is estimated within QGSjetII-04 framework simulation. [ABSTRACT FROM AUTHOR]

In this paper, we consider the problem of constructing a numerical solution to the system of equations of an acoustic medium in a fixed domain with a boundary. Physically, it corresponds to seismic wave propagation in geological media during seismic exploration of hydrocarbon deposits. The system of first-order partial differential equations under consideration is hyperbolic. Its numerical solution is constructed by applying a grid-characteristic method on an extended spatial stencil. This approach yields a higher order approximation scheme at internal points of the computational domain, but requires a careful construction of the numerical solution near the boundaries. In this paper, an approach that preserves the increased approximation order up to the boundary is proposed. Verification numerical simulations were carried out. [ABSTRACT FROM AUTHOR]

The article considers showers produced by primary particles with energies eV. The showers were registered in the course of continuous long-term observations at the Yakutsk array of extensive air showers. In the present work, the mathematical processing of showers was repeated and the phenomenology of the charged component, muons with threshold GeV in the region of highest energies was refined. Mass composition of primary particles producing air showers with energy greater than eV was made based on the muon component. [ABSTRACT FROM AUTHOR]

The paper considers the problem of choosing an initial approximation for gradient optimization methods as applied to the inverse problem of restoring the velocity distribution in a heterogeneous continuous medium. The behavior of the medium is described by a system of acoustic equations, and the direct problem is solved by applying a finite-difference scheme. L-BFGS-B is used as a gradient optimization method. The gradient of the error functional with respect to the medium parameters is calculated by applying the adjoint state method. An initial approximation for the gradient method is obtained using a convolutional neural network trained to predict the velocity distribution in a medium from its wave response. It is shown that a neural network trained on responses of simple layered structures can be successfully used to solve the inverse problem for a much more complex Marmousi model. [ABSTRACT FROM AUTHOR]

A new approach is considered for increasing the order of accuracy of the grid-characteristic method in the region of coefficient jumps. The approach is based on piecewise polynomial interpolation for schemes of the second and third orders of accuracy for the case where the interface between the media is consistent with a finite-difference grid. The method is intended for numerical simulation of the propagation of dynamic wave disturbances in heterogeneous media. Systems of hyperbolic equations with variable coefficients are used to describe the considered physical processes. The description of the numerical method and the results of its testing are given. [ABSTRACT FROM AUTHOR]

The grid-characteristic method on structured grids is applied to various problems related to railway-traffic safety, as well as to obtain results of full wave modeling using this method and analyzing them for a better understanding of the physical processes occurring under conditions of heavy and high-speed traffic on various sections of the track. The problem involves the consideration of traffic on a ballasted and ballastless bridge desk. In the course of computer simulation, various wave fields and dynamic distributions of pressure and components of the Cauchy stress tensor are obtained during the traffic. The calculation time during which the propagation of wave processes occurs in various bridge structures is estimated. The results obtained give an idea of wave phenomena during the traffic in the area of bridges and along the railway track as a whole. [ABSTRACT FROM AUTHOR]

In this paper, we consider the problem of seismic wave propagation in gradient geological media. Their dynamic behavior is described using the acoustic approximation and the numerical integration of the initial-boundary value problem for the acoustic wave equation with spatially variable mechanical parameters. A grid-characteristic numerical method is developed that explicitly takes into account the gradient of the medium. The numerical solutions are compared with results obtained using a piecewise constant model of the medium in the one-dimensional case. [ABSTRACT FROM AUTHOR]

The aim of this work is to develop a hybrid computational method that combines the grid-characteristic method on regular structured grids with the discontinuous Galerkin method on unstructured tetrahedral grids. The proposed method makes it possible to describe integration domains with complex-shaped boundaries and contact boundaries and to calculate seismic fields taking into account the topography of the Earth's surface, while saving computational resources. This modification of the method in the three-dimensional case has been proposed in this paper for the first time. Examples of using the developed method for calculating elastic wave phenomena arising during seismic prospecting are given. By way of testing, a comparison is made with results produced by the grid-characteristic method on curvilinear structured grids. The proposed hybrid method can be used not only for seismic prospecting, but also for calculating wave phenomena in other objects of complex shape. [ABSTRACT FROM AUTHOR]

Pyrolysis of various fractions of crumb rubber (with particle sizes of 0–1, 1–3, 2–3.5, and 2–4 mm) obtained from the waste largesized tires was studied in the temperature range of 550–700°C and at atmospheric pressure. It is shown that in the temperature range under study, the particle size of crumb tire rubber has only an insignificant effect on the distribution of its pyrolysis products, which consist of pyrolysis gas, pyrolysis liquid, and solid carbon residue. Pyrolysis gas is a mixture of predominantly light hydrocarbons of composition C1–C4 and hydrogen, the concentration of which increases with a rise in the heat treatment temperature; pyrolysis gas can be utilized as a fuel of the high heating value (HHV), and can also serve as a raw material for hydrogen production. The pyrolysis liquid is a mixture of alicyclic, aromatic, and linear hydrocarbons of С8–С17 composition with a rather high content of value-added products, such as limonene (up to ~35.5 wt %) and cymene (up to ~14.5 wt %); after their separation, the pyrolysis liquid can be used as heating oil or as a raw material for the production of motor fuels and valuable chemical compounds. The solid carbon residue has a relatively developed mesoporous structure (with a predominant pore size in the range of ~200–400 Å) and can be used as a raw material for the production of carbon sorbents. [ABSTRACT FROM AUTHOR]

The motion, deformation, and destruction of a thin fiber under the action of a transverse shock load are numerically simulated. The fiber is described by the equations of Rakhmatulin's theory. The system of dynamic equations is solved using the finite-difference method. The parameters for the model can be obtained directly from impact loading experiments, so the dependence of the material properties on the strain rate can be taken into account. Numerical results for aramid fibers under impact load are presented. Loading modes with and without fiber breakage are considered. A direct comparison of the numerical and experimental data is presented. A good agreement between them is demonstrated. The resulting validated numerical model of a single fiber can further be used to describe a fabric material as a system of interacting fibers. [ABSTRACT FROM AUTHOR]

We applied thermogravimetric analysis to ten successive growth rings of Siberian larch and the same number of mountain birch individuals sampled in the alpine forest-tundra ecotone of Kuznetsk Ala Tau mountain ridge to compare physical and chemical responses of the species wood to climate change. Our analysis of the correlation of the wood thermal parameters with air temperature and precipitation revealed that early and latewood cellulose and lignin in the birch were more sensitive to climatic changes as compared to the larch. June–August weather conditions appeared to largely control the chemical composition of the birch early and latewood. Air temperature had a marked influence during synthesis of both early and latewood cell walls, whereas precipitation influenced only latewood. Thermogravimetric analysis of growth rings formed in alpine forest-tundra proved to be an effective tool to study the influence of climatic and weather variability on lignin-carbohydrate complex of deciduous and conifer tree species. [ABSTRACT FROM AUTHOR]

The process of conducting seismic exploration of gas fields with a source and receivers installed on the surface of an ice island is considered. A model that includes an ice formation, water area, multilayer geological massif, and a methane reservoir is built. The dynamic behavior of individual media is described using the theory of linear elasticity, acoustic equations, Maxwell's viscoelastic model, and Kukudzhanov's viscoelastoplastic model. The governing system of equations is solved numerically by applying the grid-characteristic method on rectangular meshes. Physical contact conditions between the media are set explicitly. A new hybrid scheme of higher order accuracy is constructed using a grid-characteristic monotonicity criterion. The scheme is used to obtain a full-wave solution of a two-dimensional seismic problem. [ABSTRACT FROM AUTHOR]

We consider a multidimensional model of opinion dynamics in social networks. Within the framework of the model, the dynamics of two interconnected information processes in a social network is studied. The first process is the process of spreading of the excitation in the network of agents and their actions observed from outside (e.g., in the form of messages posted in social media). The second process, which has a connection with the first, is the formation of agents' opinions (which are a characteristic of their internal state). We demonstrate that the proposed model of opinion dynamics is flexible and allows taking into account the significant effects of opinion formation in social networks, including consensus or agreement of opinions, preservation of differences in agents' opinions, and even polarization of opinions. We propose approaches to measuring the polarization of opinions and present simulation results. We show that the proposed polarization index for a network allows one to distinguish and evaluate situations with meaningfully different multidimensional distributions of opinions in a social network as well as to find directions of the greatest polarization. [ABSTRACT FROM AUTHOR]

Fractured media are important objects of investigation, because they accumulate oil. Hydraulic fracturing is of great practical interest. The exploration of such heterogeneities with the help of mathematical modeling methods makes it possible to examine different problem formulations with fractures of different forms, sizes, and other characteristics. The Schoenberg fracture model takes into account the characteristics of the fluid inside the fracture, which is utterly important in conducting seismic geological surveys. In this work, an algorithm for computing the medium parameters at the boundary of a fracture described by the Schoenberg model is developed using the grid-characteristic method. We present the results obtained by applying the developed algorithm to the solution of the problem of seismic monitoring of a hydraulic fracture, where the fracture-filling fluid is a necessary part of the investigation. [ABSTRACT FROM AUTHOR]

Climate change entails shifts in the ranges of woody plants along both latitudinal and altitudinal gradients in the boreal forest biome. In this study, dendrochronological and GIS technologies have been used to evaluate shifts in the upper distribution limits of trees and shrubs in the Eastern Sayan Mountains. The results show that upward expansion along the altitudinal gradient and increase in projective cover against the background of climate warming reach a maximum in shrubs (Betula spp., Salix spp.); then follow Siberian larch (Larix sibirica Ledeb.), Siberian stone pine (Pinus sibirica Du Tour), and Siberian fir (Abies sibirica Ledeb). The abundance of P. sibirica undergrowth in the mountain forest–tundra ecotone has increased, which is due to a rise in May–August air temperatures (r = 0.97). In zones with sufficient moisture supply (high mountains), warming stimulates radial growth of trees and shrubs and promotes their expansion to the mountain forest–tundra. [ABSTRACT FROM AUTHOR]

The goal of this study is to develop and apply a grid-characteristic numerical algorithm for determining damage to an offshore object (ice island) by computing seismic wave propagation from an earthquake hypocenter located at a depth of several kilometers taking into account specific features of the Northern Seas (shallow depths). The grid-characteristic method on combined grids is used for this purpose. A single run involves more than 25 separate grids differing from each other in the system of equations to be solved, the type of the numerical scheme, and the step sizes in coordinates. Some of these grids make up a set of embedded hierarchical ones with a multiple step in coordinate, while the others are conformal to each other. Additionally, an improved nonreflecting condition is used, which assumes a sharp increase in the step size in coordinate and the application of a dissipative difference scheme. Special attention is given to the computational algorithms used on the boundaries and interfaces of the separate grids, which make it possible to implement the proposed approach with the use of the grid-characteristic method on combined grids. [ABSTRACT FROM AUTHOR]

The quest for lowering energy consumption during thin film growth by magnetron sputtering techniques becomes of particular importance in view of sustainable development goals. As large fraction of the process energy is consumed in substrate heating for the purpose of providing high adatom mobility necessary to grow dense films, the most straightforward strategy toward more environment-friendly processing is to find alternatives to thermally activated surface diffusion. One possibility is offered by high mass metal ion irradiation of the growing film surface, which has been recently shown to be very effective in densification of transition metal nitride layers grown with no external heating, such that Zone 2 microstructures of the structure-zone model are obtained in the substrate temperature Ts range otherwise typical for Zone 1 growth. The large mass difference between the incident ion and the atoms constituting the film results in effective creation of low energy recoils, which leads to film densification at low Ts. Due to their high mass, metal ions become incorporated at lattice sites beyond the near-surface region of intense recoil generation leading to further densification, while preventing the buildup of residual stress. The practical implementation of this technique discussed in this Perspective employs heavy metal targets operating in the high-power impulse magnetron sputtering (HiPIMS) mode to provide periodic metal-ion fluxes that are accelerated in the electric field of the substrate to irradiate layers deposited from direct current magnetron sputtering (DCMS) sources. A key feature of this hybrid HiPIMS/DCMS configuration is the substrate bias that is synchronized with heavy metal ion fluxes for selective control of their energy and momentum. As a consequence, the major fraction of process energy is used at sputtering sources and for film densification, rather than for heating of the entire vacuum vessel. Model material systems include TiN and metastable NaCl-structure Ti1−yAlyN films, which are well-known for challenges in stoichiometry and phase stability control, respectively, and are of high relevance for industrial applications. This Perspective provides a comprehensive overview of the novel film growth method. After presenting basic concepts, time-resolved measurements of ion fluxes at the substrate plane, essential for selective control of metal ion energy and momentum, are discussed. The role of metal ion mass, energy, momentum, and concentration is described in more detail. As some applications require substrate rotation for conformal coating, a section is devoted to the related complexity in the implementation of metal-ion-synchronized growth under industrial conditions. [ABSTRACT FROM AUTHOR]

The problem of seismic wave propagation in a heterogeneous geological medium is considered. The dynamic behavior of the medium is described by the linear elastic system of equations. The stratification of the medium is taken into account using the vertically transversely isotropic model. The numerical solution is obtained by applying the grid-characteristic method on parallelepipedal meshes. A new approach for the explicit solution of the contact isotropic–anisotropic problem is developed. A computational algorithm for the full-wave simulation of body and surface waves is presented. Its performance is demonstrated as applied to a two-dimensional anisotropic Marmousi-2 model. [ABSTRACT FROM AUTHOR]

The elastic effects on an artificial ice island produced by drill impacts and the pressure of structures located on the island are numerically modeled. The problem is solved numerically by applying the grid-characteristic method with interpolation on structured and unstructured meshes. The grid-characteristic method most accurately describes dynamic processes in exploration seismology problems, since it takes into account the nature of wave phenomena. The approach used makes it possible to construct correct computational algorithms at the boundaries and interfaces of the integration domain. Elastic wave propagation in the considered geological environment is studied, the stress distribution is simulated, and the stability of the ice island to fracture is analyzed using the von Mises criterion. [ABSTRACT FROM AUTHOR]

A novel non-parametric method for mutual information estimation is presented. The method is suited for informative feature selection in classification and regression problems. Performance of the method is demonstrated on problem of stable short peptide classification. [ABSTRACT FROM AUTHOR]

The distribution of the dynamic load on railroad track caused by a moving heavy train is numerically simulated. The track is represented as a multilayered linear elastic medium. A complete system of equations describing the state of a linear elastic body and a system of continuum mechanics equations are solved. The grid-characteristic method is used, which ensures the formulation of correct contact and boundary conditions. Analytical expressions taking into account the impact of damaged wheels on rails are derived, and corresponding boundary conditions are developed and numerically implemented. [ABSTRACT FROM AUTHOR]

The problem of seismic wave propagation from a source located in a well is considered. Acoustic equations are used to describe the dynamic behavior of the fluid. The damaged zone is described as a porous fluid-saturated medium by applying the Dorovsky model. The elastic approximation is used to describe the dynamic behavior of the surrounding rock. A unified algorithm based on the grid-characteristic approach with curvilinear grids is proposed for full-wave modeling in the entire computational domain. Its distinctive feature is that the necessary contact conditions on the boundary between media with different rheological properties are stated explicitly. The possibility of acoustic diagnostics of the heterogeneity of the damaged zone is numerically explored. [ABSTRACT FROM AUTHOR]

Intense methane emission from permafrost soil into the atmosphere has long been observed in Arctic shelf and coastal zones. Due to the potential danger of this phenomenon for the environment and infrastructure, there is a need for periodic monitoring of gas pockets, including by means of land seismic exploration. In the present paper, this process is studied using numerical simulation methods. In order to reflect the main specific features of the region, a model of layered permafrost sandy soil with curved boundaries between the layers is constructed. Vertical and horizontal gas migration is represented by an increase in the number of methane reservoirs. The hyperbolic equations of linear elasticity are used as a governing system. The problem is solved by applying the grid-characteristic method in the two-dimensional case. The elastic parameters of the layers are specified in each grid cell. Wave structures exhibited by the resulting synthetic wave patterns and seismograms are analyzed in detail, allowing the direction of gas migration to be determined. The results can be used to interpret similar in situ measurements. [ABSTRACT FROM AUTHOR]

Single crystalline Sc[sub 1-x]Ti[sub x]N layers, with compositions spanning the entire range (0≤x≤1), were grown on MgO(001) by ultrahigh vacuum reactive magnetron sputter deposition at 750 °C. Optical transmission and reflectivity spectra are well described by a Drude-Lorentz model. The optical carrier density N[sup *] increases linearly from 1.0x10[sup 21] for ScN to 4.6x10[sup 22] cm[sup -3] for TiN while the room-temperature electrical resistivity ρ[sub 300K] varies by more than 2 orders of magnitude, from 2x10[sup -3] Ω cm for ScN to 13 μΩ cm for TiN. ρ[sub 300K] agrees well with optically determined resistivity values for alloys with compositions up to x=0.66, corresponding to the onset of electron filling in the second and third conduction bands. We calculated ScN and TiN band structures by ab initio density functional methods and used the results to simulate the field responses of free carriers in the Sc[sub 1-x]Ti[sub x]N layers. From this, we determined, in combination with the measured temperature dependence of the resistivity, the low-temperature carrier relaxation time τ(x). The composition dependence of τ is dominated by alloy scattering and agrees well with our measured optical results. Hall experiments were used to obtain the effective carrier density N[sub eff](x) which increases linearly with x up to x=0.4. N[sub eff](x) is relatively flat for alloy compositions between x=0.4 and 0.7, due to anisotropies in the conduction band, and exhibits a steep increase at x>0.7 as higher lying conduction bands begin to be occupied. Our simulated Sc[sub 1-x]Ti[sub x]N electronic transport properties are in good agreement with experiment. Interband optical absorption results can also be understood based upon the calculated band structures. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Presents a study which reported results on the growth by reactive magnetron sputter deposition of nitride crystals. Characteristics of transition-metal nitrides; Methodology; Results and discussion; Conclusions.

Presents a study which demonstrated the growth of low-temperature fully dense polycrystalline titanium nitride (TiN) layers. Application of TiN diffusion barriers; Preparation of TiN thin films; Results of the study.

The paper presents the results of the longitudinal development of extensive air showers ( X max ) of ultra-high energies and mass composition of cosmic rays. The measurements of X max are based on data from observations of the Cherenkov radiation at the Yakutsk array for the period 1974–2014. The cascade curves of individual showers and the depth of maximum X max were reconstructed over the energy range 1016–5.7 · 1019 eV. It is shown that the displacement rate of the parameter d X max /dE in the atmosphere is nonlinear and depends on the energy. Such a feature indicates a change in mass composition, which is confirmed by fluctuations of X max in this energy region. The composition of cosmic rays was determined by interpolation using the QGSJetII-04 model. [ABSTRACT FROM AUTHOR]

The Yakutsk array is designed to study cosmic rays at energy 1015–1020 eV. The array detects charged particles, muons, Cherenkov light and radio emission. Radio-emission method is capable to study air shower physics independently of other shower components, including energy estimation of primary particle, longitudinal development of the particle cascade in the atmosphere (in the case of the Yakutsk array the depth of maximum development Xmax). For the showers with energy E ⩾ 1019 eV arrival directions were tracked and reconstructed in galactic and equatorial coordinate system to search for cosmic ray sources with such energies. [ABSTRACT FROM AUTHOR]

The paper presents results on longitudinal development of air showers with ultra-high energies and mass composition of cosmic rays 〈ln A〉. The data is obtained from observations of Cherenkov emission at the Yakutsk array in 1974–2014. Cascade curves of individual showers reconstructed by lateral distribution of Cherenkov light and depth of maximum Xmax are analyzed in the energy region 1016–6 × 1019 eV. Composition of cosmic rays is determined by interpolation of hadronic interaction QGSJETII-04 model. [ABSTRACT FROM AUTHOR]

Provides information on a study which investigated the effects of low-energy N2... ion irradiation on microstructural and texture evolution, as well as the mechanical properties, of polycrystalline and epitaxial ScN layers grown on MgO(001). Experimental procedure; Results and discussion; Conclusions.

Investigates interfacial reaction paths and kinetics during annealing of Al/W and Al/TixW1-x bilayers sputter deposited in both Ar and Xe. Observed increases in WAl4 nucleation and growth rates; Ar and Xe discharges; Incorporation of Ti concentration; Interfacial blocking layer.

Reports that polycrystalline bcc W layers were grown on amorphous-SiO2/Si(001) substrates by ultrahigh vacuum magnetron sputter deposition. As-deposited Al/W bilayers; Annealed Al/W bilayers; Interfacial reaction pathway during the annealing of polycrystalline Al/W bilayers; Role of W surface orientation and grain boundaries on Al/W bilayer interaction kinetics.

Deals with a study that examined the reaction paths and kinetics of aluminide formation in aluminum/epitaxial-W(001) model diffusion barrier systems. Importance of understanding the microchemical and microstructural interfacial reaction paths affecting the integrity of layers used in applications; Changes in bilayer sheet resistance; Determination of reaction kinetics and activation energies.

Investigates the effects of incident ion/metal flux ratio J[subi]/J[subMe] and ion energy E[subi] on the microstructure, texture and phase composition of polycrystalline metastable Ti[0.5]Al[0.5]N films produced by reactive magnetron sputtering. Description of the polycrystalline metastable Ti[0.5]Al[0.5]N films; Analysis of the microstructures of as-deposited alloys using a combination of x-ray diffractometry and transmission electron microscopy.

Provides information on a study that discussed the defect structure and phase transitions in epitaxial metastable cubic Ti[sub0.5]Al[sub0.5]N alloys grown on MgO(001) by ultra-high-vacuum magnetron sputter deposition. Occurrence of surface-initiated spinodal decomposition; Type of thin films used to increase the lifetimes of mechanical components; Areas where titanium nitride can be applied.

The problem of tsunami warning and the use of the grid-characteristic method developed for studying wave processes in heterogeneous media is addressed. A multilayer geological model with curved boundaries and contrasting elastic parameters is considered. Various seismic survey methods, as well as different geometries of the boundaries, different values of rock densities, and various longitudinal and shear wave velocities, are examined. The boundary value problem is numerically solved jointly for the elastic and acoustic wave equations (seismic wave propagation in rocks and water layer, respectively). We use the numerical grid-characteristic method with combined structured curvilinear and regular computational grids. The wave velocity fields (velocity as derivative of displacement) and stress fields are calculated and analyzed. Synthetic seismograms are calculated for the coastal zone. It is found that some specific features of seismograms and some wave modes can be used for tsunami warning. The optimal parameters of seismic surveying are determined. Numerical simulation of wave propagation effects is used for these purposes. The proposed numerical grid-characteristic method can be used in forward numerical modeling in order to interpret seismograms recorded in the coastal zone. [ABSTRACT FROM AUTHOR]

Abstract: A key difficulty faced when grid-characteristic methods on tetrahedral meshes are used to compute structures of complex geometry is the high computational cost of the problem. Formally, grid-characteristic methods can be used on any tetrahedral mesh. However, a direct generalization of these methods to tetrahedral meshes leads to a time step constraint similar to the Courant step for uniform rectangular grids. For computational domains of complex geometry, meshes nearly always contain very small or very flat tetrahedra. From a practical point of view, this leads to unreasonably small time steps (1-3 orders of magnitude smaller than actual structures) and, accordingly, to unreasonable growth of the amount of computations. In their classical works, A.S. Kholodov and K.M. Magomedov proposed a technique for designing grid-characteristic methods on unstructured meshes with the use of skewed stencils. Below, this technique is used to construct a numerical method that performs efficiently on tetrahedral meshes. [ABSTRACT FROM AUTHOR]

A complex analysis of Yakutsk EAS array data has been performed in order to search for primary photons generating extensive air showers with energies above 1018 eV. Analyzing calculations and experimental data, selection criteria have been formulated and used to make a sample of showers close in their characteristics to showers initiated by primary photons. An upper limit of the integral photon flux in cosmic rays of extremely high energies has been estimated from these data. [ABSTRACT FROM AUTHOR]

The grid-characteristic method on a sequence of embedded hierarchical grids is used to study the reflection and diffraction of elastic seismic waves propagating from an earthquake hypocenter to the Earth's surface. More specifically, the destruction caused by seismic waves in complex heterogeneous structures, such as multi-story buildings, is analyzed. This study is based on computer modeling with the use of the grid-characteristic method, which provides a detailed description of wave processes in heterogeneous media, takes into account all types of emerging waves, and relies on algorithms that perform well on the boundaries of the integration domain and material interfaces. Applying a sequence of hierarchical grids makes it possible to simulate seismic wave propagation from an earthquake hypocenter to ground facilities of interest-multi-story buildings-and to investigate their seismic resistance. [ABSTRACT FROM AUTHOR]

Spatial dynamic wave effects occurring in rocks with ravines and caverns were studied. The influence exerted by the explosion type and the cavern-to-ravine distance on the formation of spatial dynamic wave patterns and seismograms was analyzed in the case of horizontal and vertical reception lines. The gridcharacteristic method and the full wave joint numerical modeling of elastic and acoustic waves were used. [ABSTRACT FROM AUTHOR]

A mathematical model that simplifies the determination of optimal parameters ensuring the maximum viability of frozen-thawed fruit and berry cuttings was developed. Values of the minimum amount of intracellular water η1min, which minimizes the plasmolysis probability, and η2min, which minimizes the probability of intracellular ice formation, were determined with due account for the bioobject heterogeneity. Free water amounts Δη, forming ice crystals inside the cell during cryopreservation of different of fruit and berry varieties, were calculated. The optimal conditions for cutting dehydration (temperature Ti and incubation time t2, minimum amount of intracellular water ηmin) ensuring the maximum viability after drying and low-temperature adaptation to cryopreservation were selected. The individual features of the viability of frozen-thawed cuttings of different species were quantitatively reflected in the free water index Δη. The maximum viability of frozen-thawed birch and blackcurrant cuttings was achieved, when intracellular water was in the bound, vitrified state Δη = 0. The calculated Δη>0 for cuttings of different varieties of apple- and pear-trees as well as of raspberry-bushes leads to a decrease in the viability, and it is impossible to obtain viable plum, apricot or grape specimens after low-temperature cryopreservation with no bound water ηC at all. [ABSTRACT FROM AUTHOR]

[Display omitted] • (Ti 1- y Al y) 1- x W x N coatings are grown by W-HiPIMS/TiAl-DCMS under industrial conditions. • Conventional resistive heating can be replaced by high-mass metal ion irradiation. • The densification of the coatings controlled by the W ion energy and W ion dose per deposited metal atom. • The energy consumption during the pre-heating and coating stage is lowered by 70 % and 62 %, respectively. Decreasing the growth temperature to lower energy consumption and enable deposition on temperature-sensitive substrates during thin film growth by magnetron sputtering is crucial for sustainable development. High-mass metal ion irradiation of the growing film surface with ion energy controlled by metal-ion-synchronized biasing, allows to replace conventionally-used resistive heating, as was recently demonstrated in experiments involving a hybrid high-power impulse and dc magnetron co-sputtering (HiPIMS/DCMS) setup and stationary substrates. Here, we report the extension of the method to industrial scale conditions. As a model-case towards understanding the role of one-fold substrate rotation on Ti 0.50 Al 0.50 N film growth employing W+ irradiation, we investigate the effect of two parameters: W ion energy (controlled in the range 45 ≤ E W+ ≤ 630 eV by the amplitude of synchronized substrate bias voltage) and W ion dose per deposited metal atom (determined by the target power). We show that the efficient densification of coatings grown without external heating can be achieved by minimizing the thickness of DCMS-deposited Ti 0.50 Al 0.50 N layer that is exposed to an W+ ion flux, or by increasing E W + at a given Ti 0.50 Al 0.50 N thickness. [ABSTRACT FROM AUTHOR]

The levels of anti-Müllerian hormone, follicle-stimulating hormone, and testosterone were studied in rats after removal of the uterine horns, oviducts, or combined surgery. The effects of preventive salpingectomy on ovarian reserve were studied. After preventive salpingectomy, the level of anti-Müllerian hormone was low throughout the experiment, follicle-stimulating hormone increased only by the end of observation (on day 40), and testosterone level decreased only on day 10. Hysterectomy alone caused no changes in the concentrations of the studied hormones on day 10 after surgery. Salpingectomy alone reduced the concentrations of anti-Müllerian hormone and testosterone and did not change the level of follicle-stimulating hormone during this period. [ABSTRACT FROM AUTHOR]

A radio instrument and results obtained from the measurements of the 32-MHz radio signal from particles of extensive air showers (EASs) with energies E ≥ 1×10 eV are reported in brief. The data were obtained at the Yakutsk EAS array in 1987-1989 (the first series of measurements) and in 2009-2014 (new series of measurements). The radio signal from EASs with energies above 10eV was detected at the Yakutsk EAS array for the first time, including the shower with the record energy of ~2×10 eV for the Yakutsk EAS array. [ABSTRACT FROM AUTHOR]

The goal of this paper is the numerical solution of direct problems concerning hydrocarbon seismic exploration on the Arctic shelf. The task is addressed by solving a complete system of linear elasticity equations and a system of acoustic field equations. Both systems are solved by applying the grid-characteristic method, which takes into account all wave processes in a detailed and physically correct manner and produces a solution near the boundaries and interfaces of the integration domain, including the interface between the acoustic and linear elastic media involved. The seismograms and wave patterns obtained by numerically solving these systems are compared. The effect of ice structures on the resulting wave patterns is examined. [ABSTRACT FROM AUTHOR]

The measurements of the CLTE and relative elongation of two types of borosilicate glasses - LK5 and Borofloat 33 - are analyzed. A TMA7100 thermomechanical analyzer is used to measure the elongation of glass samples at temperatures from 130 to 800 K (−143 to +526°C). The relative error of indirect measurements of the CLTE and the relative thermal elongation of both types of glasses did not exceed ±5 and ±3%, respectively. Polynomial equations for obtaining fits to the measurements as a function of the temperature are presented. The results will facilitate the modeling of the characteristics of the devices which are used in microsystems engineering and fabricated by anodic deposition of silicon on glass; they can also be used to optimize the temperature regime of silicon bonding with glass. [ABSTRACT FROM AUTHOR]