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Strain-Rate Dependency of a Unidirectional Filament Wound Composite under Compression

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Computer Modeling in Engineering & Sciences 2023年第12期137卷 2149-2161页

作者： Stepan Konev victor A.Eremeyev Hamid M.Sedighi Leonid Igumnov anatoly Bragov Aleksandr Konstantinov Ayaulym Kuanyshova Ivan Sergeichev Skolkovo Institute of Science and Technologies Center for Materials TechnologiesMoscowRussia National Research Lobachevsky State University of Nizhny Novgorod Nizhny NovgorodRussia Dipartimento di Ingegneria Civile Ambientale e Architettura(DICAAR)Universitàdegli Studi di CagliariCagliari(CA)Italy Mechanical Engineering Department Faculty of EngineeringShahid Chamran University of AhvazAhvazIran Drilling Center of Excellence and Research Center Shahid Chamran University of AhvazAhvazIran

This article presents the results of experimental studies concerning the dynamic deformation and failure of a unidirectional carbon fiber reinforced plastic(T700/LY113)under *** test samples were manufactured through the filament winding of flat *** establish the strain rate dependencies of the strength and elastic modulus of the material,dynamic tests were carried out using a drop tower,the Split Hopkinson Pressure Bar method,and standard static *** samples were loaded both along and perpendicular to the direction of the reinforcing *** applicability of the obtained samples for static and dynamic tests was confirmed through finite elementmodeling and the high-speed imaging of the deformation and failure of samples during *** a result of the conducted experimental studies,static and dynamic stress-strain curves,time dependencies of deformation and the stress and strain rates of the samples during compression were *** on these results,the strain rate dependencies of the strength and elasticity modulus in the strain rate range of 0.001-6001/s are *** is shown that the strain rate significantly affects the strength and deformation characteristics of the unidirectional carbon fiber composites under *** increase in the strain rate by 5 orders of magnitude increased the strength and elastic modulus along the fiber direction by 42%and 50%,*** loading resulted in a strength and elastic modulus increase by 58%and 50%,*** average strength along the fibers at the largest studied strain rate was about *** obtained results can be used to design structural elements made of polymer composite materials operating under dynamic shock loads,as well as to build models of mechanical behavior and failure criteria of such materials,taking into account the strain rate effects.

关键词： High strain rate composites filament winding dynamic strength Split Hopkinson Pressure Bar compression

Materials for Spintronics: Magnetic and Transport Properties of Ultrathin (Monolayer Graphene)/MnO(001) and MnO(001) Films

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Journal of Modern Physics 2011年第10期2卷 1120-1135页

作者： victor Ilyasov Besarion Meshi anatoly Ryzhkin Igor Ershov Igor Nikiforov Alexey Ilyasov 不详

Results of investigations of band structure, Fermi surface and effective masses of charge carriers in the ultrathin (monolayer graphene)/MnO(001) and MnO(001) films are presented using the method of the density functional theory. Features of spin states of valence band and Fermi level as well as an interatomic interaction in these systems are discussed. A magnetic moment at Mn atom is estimated and an effect of spin polarization at atoms of oxygen and carbon has been revealed which natures are discussed. By calculations of structural energies for 2D (monolayer graphene)/MnO(001) and 2D MnO(001) a stability of these systems has been ascertained. In the 2D (monolayer graphene)/MnO(001) and 2D MnO(001) systems the band structure calculations for the 2D systems mentioned above point out that tensor components of effective masses of both electrons and holes are in the ranges of (0.15 - 0.54) m0 and (0.38 - 1.27) m0 respectively. Mobility estimations of two-dimensional charge carriers for a 2D (monolayer graphene)/MnO(001)AF2 heterostructure have been performed.

关键词： Magnetism Electron Structure Ultrathin Films Graphene Manganese Oxide Spintronics

Mykert-Sanzheevka Field of Polycomponent Ores (Pb, Zn, Ag, Au, PGE): Geologic-Substance Characteristics and Formation Features of Ore-Forming System

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Geomaterials 2020年第1期10卷 1-23页

作者： Alexander Vasilyevich Tatarinov Lyubov Ilyinichna Yalovik anatoly Georgievich Mironov victor Fedorovich Posokhov Geological Institute Siberian Branch Russian Academy of Sciences Ulan-Ude Russia

The new results of geologic-structural, petrographic and mineralogic-geochemical researches of Mykert-Sanzheevka ore field—the Uda-Vitim mineragenic zone South-West ending of West Transbaikalia are given. Its main ore-controlling structure, represented by losange, consisting of rhombohedral and tetrahedral blocks-duplexes mosaic clusters, which are separated by narrow tectonic sutures, is specified. It is clarified that polycomponent ores clusters are confined with these small-block sutures, made by subvolcanic dykes of shoshonite-latite volcano-plutonic association (233 - 188 million years), apodyke dynamometamorphites (breccias, cataclasite, mylonites) and also mechanometasomatites. Four stages of the dynamometamorphites formation characterized by different species compositions of ore minerals appeared as a result of mechanochemical reactions are determined. A carbonyl model of mineral microaggregates formation with films containing noble metal nanoparticles is proposed. Ore-forming system features of Mykert-Sanzheevka field are considered.

关键词： Polycomponent Ores Dynamometamorphism Mechanometasomatites Noble Metals Microaggregates Nanophases Trace Minerals Ore-Forming System Carbonyl Compounds Geochemical Microanomalies

2D and 3D Analysis of Magnetocardiographic Data in the Evaluation of the Ventricular Repolarization Changes under Exercise Stress Test in Patients with CAD

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World Journal of Cardiovascular Diseases 2014年第8期4卷 399-404页

作者： Illya Chaikovsky Leonid Stadnyuk Georg Mjasnikov anatoly Kazmirchuk Sergy Sofienko victor Kozlovsky Tatjana Ryzenko Ekaterina Ryschlik Mykola Budnyk Volodymyr Sekretny Institute of Cybernetics of National Academy of Sciences Kiev Ukraine M.D. Strazesko National Scientific Center of Cardiology Kiev Ukraine Main Military Clinical Hospital Kiev Ukraine Shupyk Natioinal Medical Academy of Post-Graduated Education Kiev Ukraine

Objective: Non-invasive methods of evaluation of electrical activity of the heart are still the most important functional diagnostics methods in coronary artery disease (CAD) detection. It has been shown that magnetocardiography (MCG) appears to be rather sensitive in diagnostics of chronic CAD even in the patients at rest with unchanged ECG. The objective of present paper is to investigate the influence of non-invasive tests with a physical exerciseon MCG parameters in the patients with chronic CAD. Materials and Methods: In total, 10 patients were examined (mean age 41 ± 5 years) suffering from chronic stable angina (CAD). CAD was diagnosed by clinical evidences, bicycle ergometria positive data and coronary angiography (stenosis > 70% in at least onr main coronary angiography). The control group consisted of 14 healthy volunteers. MCG mapping was performed by means of a 7-channel SQUID-magnetometer installed in an unshielded room. The MCG examination was conducted twice, whilst patients were at rest and after exercise on the bicycle (in healthy persons it was conducted immediately after exercise and in the patients, after the ST depression and/or chest pain had disappeared). The homogeneity and electric motive force (EMF) direction disturbances on magnetic field distribution maps on an extent of ST-T interval have been evaluated. Results: Statistically significant differences between groups examined based both on 2D and 3D quantitative criteria were demonstrated. Conclusion: The application of a set of MCG criteria based on the analysis both of ventricular depolarization and repolarization will enable a greater degree of accuracy for the results of the exercise stress test, especially in doubtful cases.

关键词： Magnetocardiography Coronary Artery Disease Magnetic Field Distribution Maps Exercise Stress Test Equivalent Dipole

Study of Antimicrobial Activity of Medications for Wound Treatment

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Journal of Pharmacy and Pharmacology 2015年第7期3卷 350-355页

作者： Boyko N. Nick Zaytsev I. Alexander Osolodchenko P. Tatyana Melnik L. anatoly Nevmerzhitskiy V.Vitaliy Volkov O. Taras Kazmirchuk V. victor Department of Processes and Devices of Chemical-Pharmaceutical Industries National Pharmaceutical University Kharkov61140 Ukraine Biochemistry and Biotechnology Laboratory and Antibacterial Agents Laboratory State Institution LI. Mechnikov Institute ofMicrobiology and Immunology of the National Academy of Medical Sciences of Ukraine Kharkov 6105 7 Ukraine

This paper presents data on the study of antimicrobial activity of 16 medications used for wound treatment. Antimicrobial activity of medications has been studied by well diffusion method on standard microorganism test strains： S. aureus ATCC 25923, E. coli ATCC 25922, P. aeruginosa ATCC 27853, P. vulgaris ATCC 4636, B. subtilis ATCC 6633, and C. albicans ATCC 885/653. Integrated indexes of antimicrobial activity of medications using vector theory have been calculated, which allowed to place most active of them in the order of descending activity： Levomecolum A = 2.73, r2 = 0.82; Levosin A = 2.41, r2 = 0.83; Synthomycinum A = 2.33, r2 = 0.97; Methyluracilum cum myramistino A = 2.31, r2 = 0.83; Oflocainum-Darnitsa A = 2.25, 1-2 = 0.97; and Betadine A = 2.03, r2 = 0.97. The mean of integrated indexes of antimicrobial activity and the square of the correlation coefficient for the group of these medications are as follows： A = 2.02, and r2 = 0.91. Comparison of mean values of integrated indexes of antimicrobial activity of medicines for wound treatment with those of water-alcohol extracts from plant raw material containing alkaloids, tannins, hydroquinone, naphthoquinones, anthraquinones, and phenols has shown to be promising of further development of domestic agents having antimicrobial activity based on water-alcohol extracts from plant raw material.

关键词： Antimicrobial activity wound medications well diffusion method.

Heptadecane and Gallium Crystallization in Hydrodynamic Czochralski Model

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材料科学与工程（中英文A版） 2015年第9期5卷 351-360页

作者： Vladimir Berdnikov anatoly Prostomolotov Nataliya Verezub victor Vinokurov Institute of Thermophysics Siberian Branch of Russian Academy of Sciences Novosibirsk 630090 Russia Institute for Problems in Mechanics Russian Academy of Sciences Moscow 119526 Russia

The processes of convective heat transfer and crystallization were studied on basis of the simplified, but a unified calculation-experimental Czochralski model, using two materials with the melting temperature close to ambient room temperature: 1) heptadecane with a low thermal conductivity; 2) gallium with the high one. The transparency of heptadecane melt has permitted to visualize both the melt stream structures and geometry of its crystallized mass in the laboratory experiment and to provide data for verification of the corresponding calculation model. Numerical calculations have allowed to parametrically study the flow structure, heat fluxes on the cooled disk and to assess dependence of the melt-crystal interface for both these substances on the modes of convective heat exchange: thermal-gravitational and mixed (i. e., with an additional crystal rotation) convection.

关键词：水动力模型结晶过程对流传热计算模型镓熔融温度结晶质量流动结构