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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

Energy of Grain Boundaries of Different Type in fcc Solid Solutions,Ordered Alloys and Intermetallics with L1_2 Superstructure

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Journal of Materials Science & Technology 2003年第6期19卷 593-596页

作者： O.B.Perevalova E.V.Konovalova N.A.Koneva E.V.Kozlov Institute of Strength Physics and Materials Science Russian Academy of Science Siberian Branch Russia TomskState University of Architecture and Building Russia TomskState University of Architecture and Building Russia TomskState University of Architecture and Building Russia Tomsk

The study of the triple junctions of the grain boundaries in some fee solid solutions, ordered alloys and intermetallics with L12 has been carried out using the optical metallography and TEM methods. Two-types of the triple junctions were found in the alloys investigated (1), consisting of the boundaries of the random (RT), and (2), consisting of the RT boundary and the special boundaries (ST). The relative values of the RT and ST boundary energy were determined on the basis of the measurements of the angles between the grain boundary planes. It has been shown that the energy of ST boundaries increases with the increase of the stacking fault (SF) energy. The energy of the RT boundaries does not depend on the SF energy.

关键词： Alloys Grain boundary energy Stacking fault Anti-phase-boundary

Rare and endangered plant species of the Chinese Altai Mountains

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Journal of Arid Land 2010年第3期2卷 222-230页

作者： Marina V.OLONOVA tomsk state university

Altai (also named Altay in China) Mountain Country (Mountain System) is a unique natural region,located on the border between different floristic regimes of the Boreal and ancient Mediterranean sub-kingdoms,where distribution of plant species is actually limited. It is known to have sufficient endemic floral biodiversity in the Northern Asia. Many plants of Altai Mountain System need effective care and proper conservation measures for their survival and longer-term protection. Important Plant Area identified as the IUCN (the International Union for Conservation of Nature),specified criteria attract global attention for protection of floral biodiversity across the world. The records of 71 plant species from the Chinese Altai Mountains attributed to the criterion A and the dark conifer forests of Chinese Altai Mountains satisfied the criterion C,which may help qualify to fulfill the national obligation of the Convention on Biological Diversity.

关键词： conservation Important Plant Area endemics Altai Mountain System

Fluorine-containing oxidizers for metal fuels in energetic formulations

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Defence Technology（防务技术） 2019年第1期15卷 1-22页

作者： Siva Kumar Valluri Mirko Schoenitz Edward Dreizin New Jersey Institute of Technology tomsk state university

Fluorine containing oxidizers, primarily polymers, are extensively used in pyrotechnic *** oxidizers are less explored for metalized propellants and explosives despite a potential advantage of substantial heat release combined with gaseous combustion products. This review summarizes different types of fluorinated oxidizers used in energetic formulations or of potential interest for such systems, including gases, polymers, and inorganic compounds. Types of energetic formulations employing metals and fluoropolymers are discussed in more detail, including methods used to prepare composites and resulting salient features of the obtained materials. laboratory experiments characterizing such materials, in particular, electron microscopy and thermal analysis, are discussed, showing characteristic morphologies and reaction sequences observed in different metal-fluorinated oxidizer composites. Striking similarities are noted in reaction sequences for diverse compositions hinting at possible similarities in the respective reaction mechanisms. Experiments probing ignition and combustion of metal-fluorinated oxidizer composites in laboratory conditions are also reviewed, including impact, flash heating and shock ignition. Finally, some practical performance tests for energetic formulations are described following by a brief discussion of the reaction mechanisms expected to govern ignition and combustion in various metal-fluorinated oxidizer composites. The conclusions are combined with recommendation for future research in the area of reactive metal-fluorinated oxidizer composites.

关键词： Reactive materials Composites Redox reactions Pyrotechnics Propellants Explosives

Formation of Nanoscale Intermetallic Phases in Ni Surface Layer at High Intensity Implantation of Al Ions

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Journal of Materials Science & Technology 2004年第5期20卷 583-586页

作者： I.A.Bozhko S.V.Fortuna I.A.Kurzina I.B.Stepanov E.V.Kozlov Yu.P.Sharkeev tomsk state university of Architecture & Building 2 Solyanaya pl.Tomsk 634003RussiaTomsk State University of Architecture & Building2 Solyanaya pl.Tomsk 634003RussiaTomsk State University of Architecture & Building2 Solyanaya pl.Tomsk 634003RussiaNuclear Physics InstituteTomsk Polytechnic University2a Lenin Str.Tomsk 634050RussiaTomsk State University of Architecture & Building2 Solyanaya pl.Tomsk 634003.RussiaInstitute of Strength Physics and Materials ScienceRussian Academy of Sciences2/1 Pr.AkademicheskiiTomsk 634021Russia

The results of experimental study of nanoscale intermetallic formation in surface layer of a metal target at ion implantation are presented. To increase the thickness of the ion implanted surface layer the high intensive ion implantation is used. Compared with the ordinary ion implantation, the high intensive ion implantation allows a much thicker modified surface layer. Pure polycrystalline nickel was chosen as a target. Nickel samples were irradiated with Al ions on the vacuum-arc ion beam and plasma flow source 'Raduga-5'. It was shown that at the high intensity ion implantation the fine dispersed particles of Ni3AI, NiAl intermetallic compounds and solid solution Al in Ni are formed in the nickel surface layer of 200 nm and thicker. The formation of phases takes place in complete correspondence with the Ni-AI phase diagram.

关键词： High intensive ion implantation Ion-plasma source Intermetallic nanophases

Rapid destruction of sarin surrogates by gas phase reactions with focus on diisopropyl methylphosphonate(DIMP)

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Defence Technology（防务技术） 2021年第3期17卷 703-714页

作者： Elif Irem Senyurt Mirko Schoenitz Edward L.Dreizin New Jersey Institute of Technology NewarkNJ07102USA tomsk state university TomskRussia

Rapid destruction of stockpiles of sarin and other chemical weapon agents(CWA)requires understanding and quantitative description of the relevant chemical *** reactions at elevated temperatures are of particular interest for prompt agent defeat *** methylphosphonate(DIMP)is a sarin surrogate particularly well suited to model sarin thermal decomposition and is often used in *** article is a review of different experimental methods addressing decomposition of gasified DIMP,respective results and their *** early decomposition products are propene,methylphosphonic acid,methyl(oxo)phosphoniumolate,and *** computational work using available kinetic data for fluorine and the phosphorus-fluorine bond predicted the decomposition under incineration *** using an isothermal flow reactor operated at 700-800 K were used to model DIMP decomposition as unimolecular reaction with results that were consistent with the earlier theoretical *** in dynamic environments was studied using DIMP supported on rapidly heated *** results showed different decomposition products and product sequences forming at different heating rates,suggesting the need for revised reaction ***,species quantification in such experiments is difficult because of inherent large temperature *** produced in a corona discharge was also reported to lead to rapid DIMP decomposition at low *** products were distinct from those observed at high *** tube experiments may be well suited to study decomposition of organophosphorus compounds like DIMP following their rapid heating in diverse ***,presently,only sarin surrogates other than DIMP have been investigated,and no intermediate reaction products,important for developing a validated mechanism,could be detected.

关键词： Chemical weapon agent Agent defeat Thermal decomposition Incineration Prompt reactions

Laser speckle contrast imaging for monitoring of acutepancreatitis at ischemia-reperfusion injury of thepancreas in rats

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Journal of Innovative Optical Health Sciences 2022年第1期15卷 90-102页

作者： P.A.Dyachenko(Timoshina) A.N.Bashkatov D.A.Alexandrov V.I.Kochubey V.V.Tuchin Saratov state university SaratovRussia Laboratories of biophotonics and Laser Molecular Imaging and Machine Learning National Research tomsk state university TomskRussia Saratov state Medical university SaratovRussia Institute of Precision Mechanics and Control Russian Academy of SciencesRussia A.N.Bach Institute of Biochemistry Research Center of Biotechnology of the Russian Academy of Sciences MoscowRussia

The influence of ischemia-reperfusion(I/R)action on pancreatic blood flow(PBF)and the development of acute pancreatitis(AP)in laboratory rats is evaluated in vivo by using the laser speckle contrast imaging(LSCI).Additionally,the optical properties in norm and under condition of AP in rats were assessed using a modied integrating sphere spectrometer and inverse Monte Carlo(IMC)*** results of the experimental study of microcirculation of the pancreas in 82 rats in the ischemic model are *** data obtained conrm the fact that local ischemia and changes in the blood°ow velocity of the main vessels cause and provoke acute pancreatitis.

关键词： Laser speckles contrast of speckle images adaptive algorithm microcirculation blood flow acute pancreatitis pancreas rats optical properties integrating sphere spectroscopy

Active control of friction by transverse oscillations

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Friction 2019年第1期7卷 74-85页

作者： J.BENAD K.NAKANO V.L.POPOV M.POPOV Technische Universit?t Berlin Yokohama National university National Research tomsk Polytechnic university National Research tomsk state university

The present paper is devoted to a theoretical analysis of sliding friction under the influence of in-plane oscillations perpendicular to the sliding direction. Contrary to previous studies of this mode of active control of friction, we consider the influence of the stiffness of the tribological contact in detail and show that the contact stiffness plays a central role for small oscillation amplitudes. In the present paper we consider the case of a displacement-controlled system, where the contact stiffness is small compared to the stiffness of the measuring system. It is shown that in this case the macroscopic coefficient of friction is a function of two dimensionless parameters— a dimensionless sliding velocity and dimensionless oscillation amplitude. In the limit of very large oscillation amplitudes, known solutions previously reported in the literature are reproduced. The region of small amplitudes is described for the first time in this paper.

关键词： sliding friction in-plane oscillation contact stiffness coefficient of friction active control of friction

Reduction of friction by normal *** of contact stiffness

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Friction 2017年第1期5卷 45-55页

作者： M.POPOV V.L.POPOV N.V.POPOV Berlin university of Technology Berlin 10623 GermanyTomsk Polytechnic University Tomsk 634050 RussiaTomsk State University Tomsk 634050 Russia Berlin university of Technology Berlin 10623 Germany

The present paper is devoted to a theoretical analysis of sliding friction under the influence of oscillations perpendicular to the sliding *** contrast to previous works we analyze the influence of the stiffness of the tribological contact in detail and also consider the case of large oscillation amplitudes at which the contact is lost during a part of the oscillation period,so that the sample starts to 'jump'.It is shown that the macroscopic coefficient of friction is a function of only two dimensionless parameters-a dimensionless sliding velocity and dimensionless oscillation *** function in turn depends on the shape of the contacting *** the present paper,analysis is carried out for two shapes:a flat cylindrical punch and a parabolic *** we consider 'stiff systems',where the contact stiffness is small compared with the stiffness of the *** role of the system stiffness will be studied in more detail in a separate paper.

关键词： sliding friction out-of-plane oscillation contact stiffness coefficient of friction active control of friction