bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical modelling of a gas-dust sphere scattering by SPH-IDIC method
Authors: Davydov M N , Stoyanovskaya O P , Glushko T A 
Published: December 2020

Abstract
The paper is devoted to the first application of the SPH-IDIC method to simulation of three-dimensional dusty gas flow. The expansion of a sphere consisting of gas and monodisperse fine dust into vacuum is considered as a model problem. Computing was carried out using graphic accelerators based on nVidia CUDA technology. The numerical simulations show ability of the method to deal with three-dimensional dynamics. We found that in 3D case the method kept all the advantages previously demonstrated on one-dimensional problems: robustness, efficiency and simplicity in implementation.
Experimental applicability limits investigation of Spalart-Almares turbulent model and Reynolds stresses transfer model under control of rotary-divergent flow
Authors: Kabardin I K , Yavorsky N I , Meledin V G , Kh Pravdina M , Gordienko M R , Ezendeeva D P , Kakaulin S V , Usov E V , Klimonov I A , Krotov S V , Bakakin G V , Kabardin A K 
Published: December 2020

Abstract
The work continues the work of the previous year. The mass transfer characteristics were experimentally analyzed in a rotary-divergent flow with inserted blades. The laser Doppler anemometer was used for turbulent mass transfer diagnostics. The experimental investigation was used to verify the numerical calculations. As in previous year the model of Reynolds stress transfer describes the flow in range of flow rates from 50 to 250 n.m3/h more adequately than the Spallart-Almares turbulence model.
Optical properties of polymer-graphene composites coated with gold and silver alloy nanoparticles
Authors: Boyko E V , Kostogrud I A , Smovzh D V 
Published: December 2020

Abstract
The plasmon resonance phenomenon occurring in the system of graphene-polymer-nanoparticles of an alloy of gold and silver is investigated. The possibility of controlling the attenuation of the intensity of electromagnetic radiation passing through the sample by changing the composition and thickness of the deposited coating is shown. For the investigated gold and silver alloy nanoparticles, the highest degree of radiation attenuation falls on the wavelength range from 400 to 600 nm. It was shown that by changing the composition of the nanoparticles (changing the ratio of gold and silver in the alloy), it is possible to achieve the maximum selective light attenuation by more than 2.5 times in the 500 nm region. In the 700 nm region, light attenuation by not more than 2 times is achieved. It was revealed that the use of films with different metal ratios allows us to shift the position of plasmon absorption in the entire visible wavelength range.
Experimental study of the surface tension of highly concentrated boric acid solutions applicable to VVER emergency cooling
Authors: Sakhipgareev A S , Shlepkin A S , Morozov A V 
Published: December 2020

Abstract
The results of the experimental studiesof the surface tension of aqueous solutions of boric acid in a range of concentrations of 2.5-150 gkg−1H2O are presented in the paper.As a result of a literature review, it was foundthe present information about surface tension of boric acid solutions is contradictory and does not cover the entire range of parameters characteristic of a possible emergency at nuclear power plants (NPPs) with the VVER reactor. The technique of the experimental research is described. The results of the measurements of the surface tension of aqueous solutions of boric acid are presented.The existence of the temperature dependence is confirmed.The effect of concentration on the surface tension of aqueous solutions of boric acid in the studied range of parameters is shown.
Study of unsteady thermal conductivity of a package consisting of one layer of equal-size balls
Authors: Dekhtyar R A , Ovchinnikov V V 
Published: December 2020

Abstract
The study of unsteady heat transfer of a package consisting of the equal-size balls was performed at boundary conditions of the first kind. The package was located on a horizontal surface and was limited by the walls of a cylindrical thermostat 129 mm in diameter. The experiments were carried out using glass balls with a diameter of 8.85 mm, 16.0 mm, as well as polyoxymethylene balls with a diameter of 9.0 mm. The package was filled with water. The height of the water layer was equal to the diameter of the balls. In the experiments, the time was determined during which the ball package was heated or cooled to the temperature of the thermostat. It is shown that the time of temperature equalization between the package and the thermostat depends not only on the material and size of the balls but also on the direction of the heat flux. It is shown that the heating time of one layer of equal-size balls is much shorter than the cooling time.
Structure and thermal stability of austenitic steel Fe-17%Cr-12%Ni-2%Mo-0.02%C synthesized by selective laser melting
Authors: Bazaleeva K , Tsvetkova E 
Published: December 2020

Abstract
The structural features of the Fe-17%Cr-12%NI-2%Mo-0.02%C alloy manufactured by selective laser melting (SLM) and the thermal stability of the formed structures are investigated. It is shown that crystallization cells form at SLM, the boundaries of which are volume plexes of dislocations, fixed by segregation of impurity atoms. The microhardness of such a structure is one and a half times higher than that of an alloy of the same composition in a standard hardened state. During annealing up to 800 °C, this cellular structure maintains stability while maintaining hardness indices.
Determination of the Seizure load of copper-based coatings on steel obtained by laser surfacing
Authors: Biryukov V. P. , Starostin D. A. , Klevetov D. V. 
Published: December 2020

Abstract
The paper considers the process of surfacing a copper-based powder PR-BrAlFe 9.5-1, PR-L63, PR-BrSnPb10-1.5 on 40r steel samples using continuous CO2 -laser radiation and cross-beam scanning with a frequency of 227 Hz. It is shown that the jamming load depends on the powder material and processing modes. The influence of transverse beam vibrations on the quality and productivity of the surfacing process is studied.
Metrological method for determining the surface area function of the nanohardness testers tips
Authors: Kazieva T V , Gubskiy K L , Reshetov V N , Kuznetsov A P 
Published: December 2020

Abstract
The paper describes a method for measuring the surface area function of the tips of the probes of nanohardness testers using a laser interferometer. The features of the developed system provide traceability of measurements to the standard of length through the wavelength of a stabilized source of laser radiation. In addition, it is possible to measure the parameters of the probe tip without removing it from the nanohardness tester, which allows the device not to be taken out of working condition and provides unambiguous measurements.
Cleaning the surface of products with glow discharge plasma
Authors: Arustamov V.N. , Ashurov R.KH. , Rotchtein V.M. , Ashurov KH.B. , Khudaykulov I.KH. 
Published: December 2020

Abstract
The paper presents a method for cleaning the surface of products by plasma glow ions. Before applying vacuum-plasma coating methods. The foundations of the evaluation method are formed. Methods of quality control of preparing the treated surface for the coating process based on IR spectra and Raman spectra (Raman spectra) obtained by analytical studies of the surface state of the samples are presented. Based on the analysis of the intensities of the IR and Raman spectra, the dependence of the degree of surface purity of the samples on the cleaning method used is demonstrated.
Properties of graphite to be used as a material for the T-15MD tokamak plasma-facing elements
Authors: Puntakov N A , Ayrapetov A A , Begrambekov L B , Grunin A V , Dovganyuk S S , Kaplevskiy A S , Tenishev A V , Grashin S A , Arkhipov I I 
Published: December 2020

Abstract
The results of the measurement of physical properties, sputtering yield during irradiation by hydrogen ions and a study of surface morphology modification of graphite to be used for the plasma-facing materials of the T-15MD tokamak are presented in this work.
Blocking of annihilation of Frenkel pairs by He atoms
Authors: Degtyarenko N.N. , Pisarev A.A. 
Published: December 2020

Abstract
The results of DFT modelling of blocking the annihilation of Frenkel pairs at small distances between vacancy and self interstitial atom is performed in application to “subthreshold” radiation defects formation in W. It is shown that even at small distances sufficient for spontaneous annihilation of the Frenkel pair, He atoms can suppress the annihilation near the surface. In some cases an additional vacancy can appear close to the surface thus increasing the radiation damage. It is concluded that He impurities can be an additional reason for subthreshold” radiation damage.
Coherent backscattering from an ensemble of Mie-particles immersed in a magneto-active medium
Authors: Gorodnichev E E , Rogozkin D B 
Published: December 2020

Abstract
We show that coherent backscattering of light from a disordered sample in a magnetic field can exhibit unusual features. The helicity retention in scattering from particles of the sample underlies these features. In the magnetic field parallel to the sample surface, the peak of coherent backscattering of circularly polarized light shifts from the backward direction by an angle proportional to the magnetic field strength. For linearly polarized light the coherent backscattering cone splits into two ones. The results obtained correlate well with the available experimental data.
Study of factors affecting the light shift of the CPT resonance
Authors: Chuchelov D S , Tsygankov E A , Vaskovskaya M I , Zibrov S A , Velichansky V L , Petropavlovsky S V , Yakovlev V P 
Published: December 2020

Abstract
Motivated by recent developments in atomic frequency standards employing the effect of coherent population trapping (CPT), we propose a theoretical framework for describing the CPT resonances. Our extended model includes several realistic experimental factors not accounted for in the standard approaches, namely, the FM-based technique for generating the error signal, skewed laser spectrum, etc. We provide a simple yet non-trivial analytical solution revealing the magnitude and structure of the light shift. The performance of the model is checked against numerical simulations, the agreement is good to perfect.
Automation of the construction of the soliton solutions of nonlinear Schrödinger-type equations
Authors: Kutukov A A , Kudryashov N A 
Published: December 2020

AbstractAn algorithm for constructing solitary wave solutions of nonlinear ordinary differential equations which is a variation of the simple equations method has been considered. The program was written in the Maple computer algebra system. The program has been tested on equations describing the propagation of pulses in an optical fiber.
Silicon Carbide 3C-SiC phase band structures calculation in DFT
Authors: Alimov L. E. , Anufriev A. V. , Gurskaya A. V. , Chepurnov V. I. , Puzyrnaya G. V. , Dolgopolov M. V. 
Published: December 2020

Abstract
The 3C-SiC Silicon Carbide phase doped by P, Ga, and N atoms was analyzed in the framework of Density Functional Theory. The physical parameters, changing with time due to N concentration increase, were calculated. Crucial statements about the existence of the deepest level were checked. Calculations of band structures were performed using the software applications VASP and Siesta. The plane wave basis was used in the first case and the orbital basis in the frame of the virtual crystal approach in the second one.
Structure and magnetic properties of the Co2FeAl and Co2NiSi Heusler alloy films
Authors: Malikov I V , Berezin V A , Fomin L A , Perevozchikova Yu A , Bannikova N S , Patrakov E I , Naumova L I , Semiannikova A A , Milyaev M A , Korenistov P S , Marchenkov V V 
Published: December 2020

Abstract
The structural and magnetic properties (field dependences of the magnetization in magnetic fields of up to 6 kOe) of thin-film Co2FeAl, and Co2NiSi Heusler alloys grown by pulsed laser deposition on glass and a single-crystalline Al2O3 R-plane substrate at different growth temperatures (20, 280 and 420 °C) were studied. It was found that the stoichiometric composition of the films depends on the substrate temperature during growth and repeats the composition of the target for films grown at low temperatures. The films deposited on a single crystalline Al2O3 substrate have uniaxial magnetic anisotropy in the plane.
Relationship between electrical resistance and thermal expansion coefficient in YBCO and Ti67Al33
Authors: Palchaev D K , Murlieva Zh Kh , Kh Rabadanov M , Kh Gadzhimagomedov S , Iskhakov M E , Emirov R M 
Published: December 2020

Abstract
Experimental study of thermal coefficients of both electrical resistance and volume expansion in nanostructured superconducting ceramics YBa2Cu3O7-8 and intermetallic Ti67Al33 alloy was performed. In both compounds we found a correlation between the temperature dependences of these coefficients. Formation and relaxation of charge excitations in conductors with a nonmetallic type of interatomic bonds are discussed. We point that, to explain temperature dependence of the conductivity, one should take into account an anharmonicity of atomic vibrations.
Estimation of the charge state of Th implanted in SiO2 in the different atomic environment
Authors: Kurelchuk U.N. , Borisyuk P.V. , Nikolaev A.V. , Tkalya E.V. 
Published: December 2020

Abstract
In this work the investigation of the charge states of thorium implanted in SiO2 is in different atomic environments and at different concentrations is presented.. Th was considered as interstitial and substitutional impurity in model cells of 6, 48 and 96 atoms. The estimations of the Bader effective charges of Th was derived from the electronic charge density n(r) calculated in DFT full relativistic PAW pseudopotential approximation. The change in the electron density of thorium due to the environment in the cells was estimated in comparison with the free atomic state.
The influence of type of the intermolecular interaction potential on transport properties of helium
Authors: Bogdanova Yu A , Maklashova I V , Gubin S A , Amir Zh A 
Published: December 2020

Abstract
A method for calculating the transport properties of helium based on the results of thermodynamic modeling using a theoretically equation of state obtained using perturbation theory is presented. The influence of the type of interparticle interaction potential on the accuracy of calculating the helium’s viscosity and thermal conductivity is shown in comparison with the known experimental data.
Numerical simulation of magnetizing processes of nickel nanowires and nanoballs grown in superfluid helium
Authors: Golenishchev M A , Stepanov M E , Karabulin A V , Matyushenko V I 
Published: December 2020

Abstract
The present work is dedicated to numerical modeling of magnetization processes of Ni nanoparticles ensembles acquired by pulsed laser ablation of metallic target in He II. The characteristic feature of the systems under study is their heterogeneous composition. One fraction of particles is represented by thin nanowires (with diameters of 4 nm strictly) meanwhile the other corresponds to a ball-shaped particles that can obtain diameters from 8 to 500 nm. The model was verified by comparing its calculation results with SQUID-magnetometry data.
Thermodynamic modeling of hydrogen fluid parameters at isentropic and shock wave compression
Authors: Gubin S A , Maklashova I V , Mamedov Z I 
Published: December 2020

Abstract
The thermophysical parameters of hydrogen were calculated based on the model of a theoretically substantiated wide-range equation of state constructed using the potentials of intermolecular interactions Exp-6 using perturbation theory and statistical mechanics relations. The calculation results are consistent with experimental data and calculations of other authors.
Simulation of shock wave produced by detonation of high-explosive charge in a conical shock tube
Authors: Medvedev S P , Khomik S V , Ivantsov A N , Anderzhanov E K , Tereza A M , Mikhailin A I , Silnikov M V 
Published: December 2020

Abstract
Specific features of the flow during the detonation of high-explosive charge in a conical shock tube are revealed by analyzing the results of numerical simulation. It is established that the main difference between the flow in conical geometry and the spherical case is associated with a change in the flow parameters behind the shock wave due to interaction with the bounding surface (cone wall). Comparative analysis of the calculated results shows that the real performance factor of the conical shock tube can vary both over the length and cross-section of the tube.
Analysis of the TAIGA-HiSCORE data
Authors: Samoliga V 
Published: December 2020

Abstract
TAIGA-HiSCORE is an extensive air shower array of 120 Cherenkov detectors spread over an area of 1 km2. It is designed to detect cosmic rays with energies from 50 TeV to 1000 PeV. Also TAIGA-HiSCORE is planned to use for gamma-ray astronomy in cooperation with the other installations of the TAIGA observatory. This work is dedicated to the analysis of the TAIGA-HiSCORE single-mode data. We consider a possibility to detect gamma-ray point source with excess of events from the source direction. For this purpose, a method for estimation of the signal significance is proposed. It takes into account the angular acceptance of the TAIGA-HiSCORE installation. The method is tested on the Monte-Carlo toy model.
Calibration of NICA-MPD electromagnetic calorimeter modules with cosmic muons
Authors: Bhattacharjee M , Tyapkin I , Dabrowska B , Egorov D , Shutov A , Terletskiy A 
Published: December 2020

Abstract
The large barrel-shaped, shashlyk-type electromagnetic calorimeter (ECal) is an important part of the Multi-Purpose Detector (MPD) of the heavy-ion NICA experiment, and is designed to provide spatial and energy measurements for photons and electrons in the energy range from 40 MeV to 2–3 GeV. To deal with the high multiplicity, the ECal is finely segmented and made up of 38,400 cells (‘towers’) which are grouped into modules of 16 ‘towers’ each. ECal projective geometry of the ‘towers’ oriented towards the beam interaction zone results in 8 different types of modules depending on their position in the ECal. As beam calibration of each individual ‘tower’ is time and resource expensive, we discuss our strategy of calibration for the ECal modules with cosmic muons and present some preliminary results.
Implementation of the DAQ software in the ALTI Module of the ATLAS TileCal
Authors: Tlou H 
Published: December 2020

Abstract
The Tile Calorimeter (TileCal) is the central hadronic calorimeter (|η| < 1.7) of the ATLAS experiment, made out of iron plates and plastic scintillators. The TileCal is divided into three barrels along the beam axis, each of which is azimuthally segmented into 64 wedge-shaped modules, staggered in the 0 direction. TileCal online software is a set of Trigger and Data Acquisition (TDAQ) software, and its main purpose is to readout, transport and store physics data originating from collisions at the Large Hadron Collider (LHC). The ATLAS Local Trigger Interface (ALTI) module is a new electronic board, designed for the ATLAS experiment at CERN, a part of the Timing, Trigger and Control (TTC) system. It is a 6U VME module which integrates the functionalities of four legacy modules, currently used in the experiment: Local Trigger Processor, Local Trigger Processor interface, TTC VME bus interface and the TTC emitter. ALTI module will provide the interface between the Level-1 Central Trigger Processor and the TTC optical broadcasting network to the Front-End (FE) electronics of each of the ATLAS sub-detectors. There is a need to develop and integrate the ALTI software in the Tile online software. Performance tests and maintenance of the ALTI module software will be carried out during the Long Shutdown 2 period (LS2), in preparation for Run 3 data-taking period.
Masses of two Higgs doublets within effective theory with four-quark interactions
Authors: Osipov A A , Khalifa M M 
Published: December 2020

Abstract
The composite Higgs scenario in the context of the effective model with SU(2)
L
× U(1)
R
symmetric four-fermion interaction proposed by Miransky, Tanabashi and Yamawaki (MTY) is considered. The low-energy dynamics of the model is described by the effective Lagrangian obtained by the Schwinger-DeWitt technique. The questions of the Nambu sum rule and the spectrum of Higgs states are addressed in detail.
Vibrations of thick domain walls: How to avoid no-go theorem
Authors: Gani V A 
Published: December 2020

Abstract
The asymptotic properties of the stability potentials of kinks with power-law tails are discussed. In particular, in cosmology such kinks can describe “thick” domain walls. The discrete part of the domain wall excitation spectrum, the profile of which is described by a kink solution with one or both power-law asymptotics, cannot contain levels other than zero (translational) mode. Nevertheless, it can be shown that scenarios are quite possible when long-lived localized vibrations will be excited on the domain wall. This, in turn, can affect the processes of interaction of two or more domain walls.
Approaches in centrality measurements of heavy-ion collisions with forward calorimeters at MPD/NICA facility
Authors: Volkov V , Golubeva M , Guber F , Ivashkin A , Karpushkin N , Morozov S , Musin S , Strizhak A 
Published: December 2020

Abstract
The MPD/NICA heavy-ion experiment is now under construction at JINR, Dubna, Russia. The centrality is the global characteristic of the nuclear interactions and reflects the degree of the nuclei overlapping or the number of interacting nucleons. One of the methods to measure the centrality is the determination of the number of non-interacting projectile fragments (spectators) which will be detected by the hadron calorimeters (FHCal) placed at the opposite sides of the beam interaction point. Since the bound spectators escape in beam holes, the central and peripheral collisions have the same spectator’s energy deposition in FHCal. It leads to the ambiguity in the determination of the collision centrality. To resolve this ambiguity a few approaches are developed based on the Monte-Carlo simulations with a few fragmentation models. The methods are based on the combination of both the spatial and the energy distributions of the spectators in the FHCal modules. A few observables for the centrality determination are constructed. Calculation of the transverse/longitudinal energies and the two-dimensional fit of the energy distributions in the FHcal modules make possible the separation of the central and peripheral events. The accuracy of the centrality measurements for a few fragmentation models is estimated.