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Unveiling the Nature of Polar-ring Galaxies from Deep Imaging

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Research in Astronomy and Astrophysics 2022年第11期22卷 34-50页

作者： Aleksandr v.Mosenkov vladimir P.Reshetnikov Maria N.Skryabina Zacory Shakespear Department of Physics and Astronomy N283 ESCBrigham Young UniversityProvoUT 84602USA Central(Pulkovo)Astronomical Observatory Russian Academy of SciencesPulkovskoye Chaussee 65/1196140 St.PetersburgRussia St.Petersburg State University 7/9 Universitetskaya Nab.199034 St.PetersburgRussia

General structural properties and low surface brightness tidal features hold important clues to the formation of *** this paper,we study a sample of polar-ring galaxies(PRGs)based on optical imaging from the Sloan Digital Sky Survey Stripe 82 and other deep *** investigate the deepest images of candidates for PRGs to *** carry out photometric decomposition on the host galaxies and associated polar structures that allows us to derive the structural properties of both *** are able to detect very faint tidal structures around most PRGs in our *** several galaxies,we can directly observe the formation of the polar ring due to merging,which is manifested in debris of the victim galaxy and an arc-like polar structure made up of its *** a few cases,we can discern signs of tidal *** results obtained indicate that the gravitational interaction and merging of galaxies are the most plausible mechanisms for the formation of PRGs.

关键词： data analysis techniques:photometric galaxies:structure

A Three-Dimensional Multi-scale Plasticity Model for Metal-Intermetallic Laminate Composites Containing Phases of the L12 Structure

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Acta Metallurgica Sinica(English Letters) 2018年第12期31卷 1265-1271页

作者： Yana D.Lipatnikova vladimir A.Starenchenko Yuliya v.Solov'eva Larisa A.valuiskaya Tomsk State University of Architecture and Building Solyanaya Sq.2TomskRussia 634003 Siberian State Medical University 2 Moskovsky traktTomskRussia 634055

A three-dimensional plasticity model was developed and applied to metal-intermetallic laminate composites containingphases of the L12 structure. A multi-scale approach that combined the methods of continuum mechanics and dislocationkinetics was used. This model takes account of the different mechanisms of self-locking superdislocations, the dislocationsand the dislocation walls＇ density storage for each type of layer at the micro-scale. At the meso-scale, the solutions to thedislocation kinetics equations, in the form of stress-strain curves, were used to create the properties of a three-dimensionalrepresentative element. The numerical simulation study of the macroscopic deformation was carried out with the finiteelement method using the dynamic model of continuum mechanics, which included the classical conservation laws,constitutive equations and the equation of state. It was shown that the simulation results generated using this model were ingood agreement with the mechanical tests conducted on the single crystals of the L12 structure. The model provides anexcellent description of the high-temperature plastic strain superlocalization effect of single crystal intermetallics of theLI2 structure. This paper describes the numerical results of the study of the tension and compression tests of metal-intermetallic laminate composites containing phases of the L12 structure. The model allows the description of the dis-tribution of the accumulated plastic strain inhomogeneities and is capable of predicting the strengthening properties andplastic behaviour of the metal-intermetallic laminate composites containing phases of the L12 structure.

关键词： Plasticity model Metal-intermetallic laminate composites Layered composites L12 structure Tension Compression

Modification of titanium surface via Ag-,Sr-and Si-containing micro-arc calcium phosphate coating

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Bioactive Materials 2019年第1期4卷 224-235页

作者： Mariya B.Sedelnikova Ekaterina G.Komarova Yurii P.Sharkeev Anna v.Ugodchikova Tatiana v.Tolkacheva Julietta v.Rau Evgeny E.Buyko vladimir v.Ivanov vladimir v.Sheikin Institute of Strength Physics and Materials Science of SB RAS Academicheskii Prospect 2/4Tomsk634055Russia National Research Tomsk Polytechnic University Lenina Prospect 30Tomsk634050Russia Istituto di Struttura della Materia Consiglio Nazionale delle Ricerche(ISM-CNR)Via del Fosso del Cavaliere 10000133 RomaItaly Siberian State Medical University Moscovskii Tract 2Tomsk634050Russia

The current research is devoted to the study of the modification of the titanium implants by the micro-arc oxidation with bioactive calcium phosphate coatings containing Ag or Sr and Si *** coatings’microstructure,phase composition,morphology,physicochemical and biological properties were examined by scanning electron microscopy(SEM),transmission electron microscopy(TEM),energy-dispersive X-ray spectroscopy(EDX)and X-ray diffraction(XRD).Ag-containing and Sr-Si-incorporated coatings were formed in alkaline and acid electrolytes,*** formation of the coatings occurred at different ranges of the applied voltages,which led to the significant difference in the coatings *** trace elements Ag,Sr and Si participated intensively in the plasma-chemical reactions of the micro-arc coatings ***-containing coatings demonstrated strong antibacterial effect against Staphylococcus aureus AТСС*** in vitro test with 3T3-L1 fibroblasts showed no cytotoxicity appearance on Sr-Si-incorporated coatings.

关键词： Trace elements Biocoatings Micro-arc oxidation Titanium substrate Antibacterial activity

Advanced virtual prototyping for cyber-physical systems using RISC-v: implementation, verification and challenges

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Science China(Information Sciences) 2022年第1期65卷 5-21页

作者： vladimir HERDT Rolf DRECHSLER Institute of Computer Science University of Bremen Cyber-Physical Systems DFKI Gmb H

virtual prototypes(vPs) are crucial in today’s design flow. vPs are predominantly created in System C transaction-level modeling(TLM) and are leveraged for early software development and other system-level use cases. Recently, virtual prototyping has been introduced for the emerging RISC-v instruction set architecture(ISA) and become an important piece of the growing RISC-v ecosystem. In this paper, we present enhanced virtual prototyping solutions tailored for RISC-v. The foundation is an advanced open source RISC-v vP implemented in System C TLM and designed as a configurable and extensible *** scales from small bare-metal systems to large multi-core systems that run applications on top of the Linux operating system. Based on the RISC-v vP, this paper also discusses advanced vP-based verification approaches and open challenges. In combination, we provide for the first time an integrated and unified overview and perspective on advanced virtual prototyping for RISC-v.

关键词： virtual prototyping RISC-v SystemC TLM verification

Experimental study of coal fracture dynamics under the influence of cyclic freezing-thawing using shear elastic waves

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International Journal of Coal Science & Technology 2021年第4期8卷 562-574页

作者： Petr v.Nikolenko Svetlana A.Epshtein vladimir L.Shkuratnik Polina S.Anufrenkova Polina Scientific and Training Testing Laboratory of Physics and Chemistry of Coals National University of Science and Technology MISiSMoscowRussian Federation 119049 S.Anufrenkova1

Cyclic freezing-thawing can lead to fracture development in coal,affecting its mechanical and consumer *** study crack formations in coal,an ultrasonic sounding method using shear polarized waves was *** of three coal types(anthracite,lignite and hard coal)were *** research results show that,in contrast to the shear wave velocity,the shear wave amplitude is extremely sensitive to the formation of new cracks at the early stages of cyclic *** also show an inverse correlation between coal compressive strength and its tendency to form cracks under temperature impacts;shear wave attenuation increases more sharply in high-rank coals after the first freezing *** analysis of the received signals also confirmed significant crack formation in anthracite after the first freeze-thaw *** initial anisotropy was determined,and its decrease with an increase in the number of freeze-thaw cycles was *** data obtained forms an experimental basis for the development of new approaches to preserve coal consumer properties during storage and transportation under severe natural and climatic conditions.

关键词： Coal Cyclic freezing-thawing Ultrasonic Shear wave Fracture dynamics

Study of cobalt ferrite nanosuspensions for low-frequency ferromagnetic hyperthermia

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Particuology 2008年第5期6卷 322-333页

作者： Bronislav E.Kashevsky vladimir E.Agabekov Sergei B.Kashevsky Katsiaryna A.Kekalo Elena Yu.Manina Igor v.Prokhorov vladimir S.Ulashchik A.v.Luikov Heat and Mass Transfer Institute Belarus Academy of Sciences P.Brovka Str.15Minsk 220072Belarus Institute of Chemistry of New Materials Belarus Academy of SciencesSkoriny Str.36Minsk 220141Belarus Institute of Physiology Belarus Academy of SciencesAkademicheskaiy Str.28Minsk 220072Belarus

High-coercive cobalt ferrite nanoparticles were synthesized and studied for magnetic hyperthermia by direct injection of their suspension into a tumor and application of a strong audio-frequency magnetic field for heating. Physical （dynamic magnetic hysteresis and heat generation in both liquid and solid dispersions）, biological （toxicity and penetration of particles in therapeutic quantities into mouse tumor tissue） as well as other properties of the particles were studied. A model was developed to describe the magnetodynamics in suspensions of magnetic nanoclusters with an account for both Brownian and regular rotations, to provide understanding of observed phenomena. The experimental and theoretical techniques developed have formed a basis for controllable synthesis of the magnetic nanoparticles for low-frequency heat generation in medical and other applications.

关键词： Cobalt ferrite nanoparticles Magnetic suspensions Dynamic magnetic hysteresis Medical hyperthermia

Fusion Material Studies Relating to Safety in Russia in 2002

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Plasma Science and Technology 2004年第5期6卷 2496-2502页

作者： B.N.Kolbasov M.I.Guseva B.I.Khripunov Y.v.Martvnenkc P.v.romanov S.A.Lelekhov S.A.Bartenev Russian Research Centre "Kurchatov Institute" Kurchatov Sq. 1 123182 Moscow Russia RF Federal Agency for Atomic Energy Staromonetnyj pereulok 26 109180 Moscow Russia v. G. Khlopin Radium Institute 2nd Murinsky avenue 28 194021 St.-Petersburg Russia

The paper is a summary of Russian material studies performed in frames of activi-ties aiming at substantiation of safety of the International Thermonuclear Experimental Reactor(ITER)after *** sputtering of tungsten by 5 ev deuterons was revealed at temper-atures above 1150℃.Mechanism of globular films formation was further *** of tritium permeation into vacuum vessel coolant confirmed the acceptability of vacuum vessel cooling system for removal of the decay *** most dangerous accident with high-current are in toroidal superconducting magnets able to burn out a bore up to 0.6 m in diameter in the cryostat vessel was *** reprocessing of v-Cr-Ti alloy and its purification from activation products down to a contact dose rate of~10μSv/h was developed.

关键词： fusion reactor materials plasma-materials interaction vanadium and vanadium alloys

Finite-element analysis of scattering parameters of surface acoustic wave bandpass filter formed on barium titanate thin film

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International Journal of Smart and Nano Materials 2018年第2期9卷 88-98,I0002页

作者： Pavel E.Timoshenko valery v.Kalinchuk vladimir B.Shirokov Department of Nanotechnology Southern Federal UniversityRostov-on-DonRussia Southern Scientific Center RAS Rostov-on-DonRussia

The frequency dependence of scattering parameters of interdigital surface acoustic wave transducers placed on ferroelectric barium titanate(BaTiO_(3))epitaxial film in c-phase coated over magnesium oxide has been studied using the finite-element method(FEM)approach along with the perfectly matched layer(PML)*** interdigital transducer which has a comb-like structure with aluminum electrodes excites the mechanical *** distance between the fingers allows tuning the frequency properties of the wave *** magnesium oxide is taken as the *** two-dimensional model of two-port surface acoustic wave filter is created to calculate scattering parameters and to show how to design the fixture in COMSOL_(TM).Some practical computational challenges of finite element modeling of SAW devices in COMSOL_(TM)are *** effect of lattice misfit strain on acoustic properties of heterostructures of BaTiO_(3)epitaxial film in c-phase at room temperature is discussed in present article for two lowfrequency surface acoustic resonances.

关键词： SAW filters ferroelectrics thin films finite element method(FEM) COMSOL

Convective Instability and Appearance of Structured Flows for Diffusion in Multicomponent Gas Mixtures

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Transactions of Nanjing University of Aeronautics and Astronautics 2014年第2期31卷 142-146页

作者： vladimir N. Kossov~ Olga v. Fedorenko Yelena A. Dyachenko Kazakh National Pedagogical University Almaty 050100 Republic of Kazakhstan Institute of Experimental and Theoretical Physics al-Farabi Kazakh National University Almaty 050038 Republic of Kazakhstan Kazakh Academy of Transport and Communications Names after M. Tynyshpayev Almaty 050012 Republic of Kazakhstan

The main objective of this article is to investigate the behavior of gaseous systems with two and more independent gradients or thermodynamic forces exhibiting complicated behavior,when the convective flows *** existence of structural formations in these systems is shown by the schlieren method and the fast-response *** linear analysis of stability can explain reasons of the appearance of convective instability in multicomponent gas mixtures.

关键词： diffusion instability of mechanical equilibrium theory of stability partial Rayleigh numbers