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Macrocellular vitreous carbon with the improved mechanical strength

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Frontiers of Materials Science 2015年第4期9卷 413-417页

作者： oleg SMORYGO Alexander MARUKOVICH Vitali MIKUTSKI Andika PRAMONO Powder Metallurgy Institute National Academy of Sciences of Belarus 41 Platonov str. Minsk 220005 Belarus Research Centre for Metallurgy and Materials Indonesian Institute of Sciences (LIPI) Kawasan Puspitek 470 Serpong 15314 Banten Indonesia

Vitreous carbons with regular macrocellular structure, open intercon- nected porosity, high specific strength and hydraulic permeability were synthesized by infiltration of the epoxy resin into the sacrificial template made from the carbamide granules. Polyvinylpyrrolidone （PVP） solution in ethanol was used as the template binder. When the resin setting and the template extraction had been performed, the resultant porous material was pyrolysed in the nitrogen flow. Depending on PVP concentration in the template binder, final vitreous carbons had the following properties： bulk density at 0.17-0.22g/cm3; porosity at 85.7%-89.0%; window size at 447-735pm; Darcian permeability coefficient at （0.64-9.5）×10-9m2; non-Darcian permeability coefficient at （0.53-3.36）×10-4 m. High specific strength of above 8×10^3 Pa/（kg.m-3） was attained.

关键词： vitreous carbon cellular material porous material

A new non-electrolytic aluminum extraction method

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Transactions of Nonferrous Metals Society of China 2016年第9期26卷 2509-2517页

作者： oleg G.PARFENOV Andrey D.KUSTOV Leonid A.SOLOVYOV Institute of Chemistry and Chemical Technology of SB RAS

A new method of primary aluminum extraction from alumina was proposed. The method is based on the new reaction AlI3＋（3/2）Zn=Al＋（3/2）ZnI2. In its turn, the exchange reaction AlCl3＋CaI2→AlI3＋CaCl2 is used to get aluminum iodide from aluminum chloride—the product of alumina carbochlorination. These reactions were studied in laboratory experiments as well as additional reactions, which were needed for the main chemicals recycling： Cl2, ZnI2→Zn, CaCl2→CaI2. XRD and SEM methods were used to investigate the phases and morphology of the reaction＇s solid products. The global free energy minimization method was used for the chemical equation＇s calculations. It was shown that aluminum can be effectively extracted from alumina without electrolysis, extreme high temperature and expended chemicals. The estimated specific carbon consumption and CO2 atmospheric pollution rate have to be halves of such values for the contemporary aluminum plant powered by the coal power station.

关键词： aluminum aluminum alloy chlorides iodides zinc iodine high-speed metallurgy

A case of vitiligo after COVID-19 vaccination: a possible role of thymic dysfunction

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2023年第12期24卷 1141-1150页

作者： Denis KUZNETSOV oleg KALYUZHIN Andrey MIRONOV Valery NESCHISLIAEV Anastasiia KUZNETSOVA G.N.Gabrichevsky Scientific and Research Institute of Epidemiology and Microbiology Moscow 125212Russia I.M.Sechenov First Moscow State Medical University Moscow 119991Russia Perm State Pharmaceutical Academy Perm 614990Russia

During the coronavirus disease 2019(COVID-19)pandemic,vaccines help control the spread of *** date,47 vaccines have been approved,with another 227 candidates in various stages of *** the short period of time since the beginning of their use,evidence has begun to emerge of complications following vaccination in the form of the development or exacerbation of a number of pathological conditions(Block et al.,2022;Haseeb et al.,2022).For example,a population-based study in France identified 1612 cases of myocarditis and 1613 cases of pericarditis requiring hospital treatment within five months of vaccination(le Vu et al.,2022).

关键词： vaccination vaccines

Evolution of Close Binary System Parameter Distributions

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Research in Astronomy and Astrophysics 2022年第10期22卷 141-147页

作者： Dugasa Belay Zeleke Seblu Humne Negu oleg Yu.Malkov Ethiopian Space Science and Technology Institute(ESSTI) Entoto Observatory and Research Center(EORC)Astronomy and Astrophysics Research and Development DepartmentP.O.Box 33679 Addis AbabaEthiopia Institute of Astronomy Russian Academy of Sciences48 Pyatnitskaya St.Moscow 119017Russia

In this paper,we investigate the orbital and stellar parameters of low-and intermediate-mass close binary *** use models,presented in the catalog of Han et *** calculate parameters of *** also construct distributions of systems along luminosity,semimajor axis and angular momentum,and make some conclusions on their evolution with *** compare the results with observational data and it shows a good *** set of theoretical models published quite adequately describes the observational data and,consequently,can be used to determine the evolutionary path of specific close binary systems,their initial parameter values and final stages.

关键词： (stars:)binaries(including multiple) close-stars low-mass-stars mass-loss

A class of high-mobility layered nanomaterials by design

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Journal of Materials Science & Technology 2023年第33期164卷 179-187页

作者： Dmitry V.Averyanov Ivan S.Sokolov oleg E.Parfenov Alexander N.Taldenkov oleg A.Kondratev Andrey M.Tokmachev Vyacheslav G.Storchak National Research Center “Kurchatov Institute” Kurchatov Sq.1Moscow 123182Russia

Design of materials with particular functional properties is indispensable albeit very *** and structural analogies can be helpful in this endeavor,especially when a particular combination of properties is sought *** aim is to bundle together 3 characteristics:high carrier mobility,magnetism,and scalability to nanomaterials in the form of a film–such a combination is particularly advantageous for ***,inspired by recent studies of MAl_(2)Si_(2)and related compounds,we develop magnetic EuAl_(2)Ge_(2)and non-magnetic SrAl_(2)Ge_(2)nanomaterials with high carrier *** syntheses employing sacrificial 2D templates result in epitaxial films of MAl_(2)Ge_(2)seamlessly integrated with *** syntheses are followed by a study of the atomic structure,magnetic and electron transport *** particular,the films demonstrate high carrier mobility,exceeding 10,000 cm^(2)V^(-1)s^(-1)in the case of EuAl_(2)Ge_(2),making the materials appealing for *** together,MAl_(2)Ge_(2)and MAl_(2)Si_(2)form a class of high-mobility layered nanomaterials.

关键词： High carrier mobility Magnetism SrAl_(2)Ge_(2) EuAl_(2)Ge_(2) Germanium

Impact and Friction Sensitivity of Energetic Materials：Methodical Evaluation of Technological Safety Features

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火炸药学报 2015年第3期38卷 1-8页

作者： Aleksandr Smirnov oleg Voronko Boris Korsunsky Tatyana Pivina Bakhirev State Scientific Research Institute of Mechanical Engineering DzerzhinskNizhny Novgorod Region 606002Russia Institute of Problems of Chemical Physics Russian Academy of SciencesChernogolovkaMoscow Region142432Russia Zelinsky Institute of 0rganic Chemistry Russian Academy of SciencesMoscow119991Russia

Key methods developed and used in the USSR and in the Russian Federation to determine the impact and friction sensitivity of energetic materials and explosives have been *** methodologies and instruments that underlie the assessment of their production and handling safety have been *** of a large number of compounds have revealed relationships between their sensitivity parameters and structure of individual compounds and *** range of change of physical and chemical characteristics for the compounds we examined covers the entire region of their *** methodology and equations have been formulated to estimate the impact and friction sensitivity parameters of energetic materials and to evaluate the technological safety in *** developed methodology is characterized by high-accuracy calculations and prediction of sensitivity parameters.

关键词： energetic materials experimental testing friction sensitivity impact sensitivity regressive analysis safety in use methodical evaluation

Eye movement prediction by oculomotor plant Kalman filter with brainstem control

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控制理论与应用（英文版） 2009年第1期7卷 14-22页

作者： oleg V.KOMOGORTSEV Javed I.KHAN Department of Computer Science Texas State University-San Marcos Department of Computer Science Kent State University

Our work addresses one of the core issues related to Human Computer Interaction （HCI） systems that use eye gaze as an input. This issue is the sensor, transmission and other delays that exist in any eye tracker-based system, reducing its performance. A delay effect can be compensated by an accurate prediction of the eye movement trajectories. This paper introduces a mathematical model of the human eye that uses anatomical properties of the Human Visual System to predict eye movement trajectories. The eye mathematical model is transformed into a Kalman filter form to provide continuous eye position signal prediction during all eye movement types. The model presented in this paper uses brainstem control properties employed during transitions between fast （saccade） and slow （fixations, pursuit） eye movements. Results presented in this paper indicate that the proposed eye model in a Kalman filter form improves the accuracy of eye movement prediction and is capable of a real-time performance. In addition to the HCI systems with the direct eye gaze input, the proposed eye model can be immediately applied for a bit-rate/computational reduction in real-time gaze-contingent systems

关键词： Eye movement prediction Bio engineering Human computer interaction

Virtual welding equipment for simulation of GMAW processes with integration of power source regulation

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Frontiers of Materials Science 2011年第2期5卷 79-89页

作者： Uwe REISGEN Markus SCHLESER oleg MOKROV Alexander ZABIROV ISF - Welding and Joining Institute RWTH Aachen University Germany

A two dimensional transient numerical analysis and computational module for simulation of electrical and thermal characteristics during electrode melting and metal transfer involved in Gas-Metal-Arc-Welding （GMAW） processes is presented. Solution of *** transient heat transfer equation is carried out using a control volume finite difference technique. The computational module also includes controlling and regulation algorithms of industrial welding power sources. The simulation results are the current and voltage waveforms, mean voltage drops at different parts of circuit, total electric power, cathode, anode and arc powers and arc length. We describe application of the model for normal process （constant voltage） and for pulsed processes with U/I and Ill- modulation modes. The comparisons with experimental waveforms of current and voltage show that the model predicts current, voltage and electric power with a high accuracy. The model is used in simulation package SimWeld for calculation of heat flux into the work-piece and the weld seam formation. From the calculated heat flux and weld pool sizes, an equivalent volumetric heat source according to Goldak model, can be generated. The method was implemented and investigated with the simulation software SimWeld developed by the ISF at RWTH Aachen University.

关键词： GMAW process simulation regulation algorithm power source

Modified virtual internal bond model based on deformable Voronoi particles

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Theoretical & Applied Mechanics Letters 2020年第2期10卷 87-91页

作者： oleg Konovalov Shunying Ji Michael Zhuravkov Research Laboratory of Information Technologies and Computer Graphics Belarusian State UniversityMinsk 220030Belarus DUT-BSU Joint Institute Dalian University of TechnologyDalian 116023China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116023China Department of Theoretical and Applied Mechanics Belarusian State UniversityMinsk 220030Belarus

In last time,the series of virtual internal bond model was proposed for solving rock mechanics *** these models,the rock continuum is considered as a structure of discrete particles connected by normal and shear springs(bonds).It is well announced that the normal springs structure corresponds to a linear elastic solid with a fixed Poisson ratio,namely,0.25 for threedimensional *** the shear springs used to represent the diversity of the Poisson ***,the shearing force calculation is not rotationally invariant and it produce difficulties in application of these models for rock mechanics problems with sufficient *** this letter,we proposed the approach to support the diversity of the Poisson ratio that based on usage of deformable Voronoi cells as set of *** edges of dual Delaunay tetrahedralization are considered as structure of normal springs(bonds).The movements of particle’s centers lead to deformation of tetrahedrals and as result to deformation of Voronoi *** each bond,there are the corresponded dual face of some Voronoi *** can consider the normal bond as some beam and in this case,the appropriate face of Voronoi cell will be a cross section of this *** during deformation the Voronoi face was expand,then,according Poisson effect,the length of bond should be *** above mechanism was numerically investigated and we shown that it is acceptable for simulation of elastic behavior in 0.1–0.3 interval of Poisson *** surprise is that proposed approach give possibility to simulate auxetic materials with negative Poisson’s ratio in interval from–0.5 to–0.1.

关键词： Discrete element method Real multi-dimensional internal bond Voronoi tessellation Micromechanical poisson ratio Barycentric coordinates Auxetic effects