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Vibrational Suspension of Two Cylinders in a Rotating Liquid-Filled Cavity with a Time-Varying Rotation Rate

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Fluid Dynamics & Materials Processing 2024年第9期20卷 2127-2137页

作者： Olga Vlasova Laboratory of Vibrational Hydromechanics Perm State Humanitarian Pedagogical UniversityPermSibirskaya614990Russia

The dynamics of rotating hydrodynamic systems containing phase inclusions are interesting due to the related widespread occurrence in nature and *** influence of external force fields on rotating systems can be used to control the dynamics of inclusions of various *** inclusions is of current interest for space *** low gravity,even a slight vibration effect can lead to the appearance of a force acting on phase inclusions near a solid *** vibrations are applied to multiphase hydrodynamic systems,the oscillating body intensively interacts with the fluid and introduces changes in the related flow *** in the fluid flow lead to the appearance of an averaged *** a result,the body is repelled from the cavity boundary and takes a position at a certain distance from *** vibrationally-induced movement of phase inclusions in liquids can be used to improve various technological processes(for example,when degassing and cleaning liquids from solid inclusions,mixing various components,etc.).This study presents a relevant methodology to study the averaged vibrational force acting on a pair of free cylindrical bodies near the oscillating wall of a *** is paid to the region of moderate and low dimensionless frequencies when the size of the inclusion is consistent with the thickness of the Stokes boundary *** dynamics of these bodies is considered in a horizontal cylindrical cavity with a fluid undergoing modulated *** average lift force of a vibrational nature is measured by the method of quasi-stationary suspension of bodies whose density differs from the density of the liquid in a static centrifugal force *** developed technique makes it possible to determine the dependence of the lift force on vibration parameters and the distance from the oscillating boundary at which solid inclusions are *** is shown that in the region of moderate dimensionless frequencies,the averag

关键词： Solid bodies rotational oscillations viscous fluid lift force

Oscillatory Dynamics of a Spherical Solid in a Liquid in an Axisymmetric Variable Cross Section Channel

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Fluid Dynamics & Materials Processing 2024年第6期20卷 1219-1232页

作者： Ivan Karpunin Laboratory of Vibrational Hydromechanics Perm State Humanitarian Pedagogical UniversityPerm614990Russia

The dynamics of a solid spherical body in an oscillating liquid flow in a vertical axisymmetric channel of variable cross section is experimentally *** is shown that the oscillating liquid leads to the generation of intense averaged flows in each of the channel *** intensity and direction of these flows depend on the dimensionless oscillating *** the region of studied frequencies,the dynamics of the considered body is examined when the primary vortices emerging in the flow occupy the whole region in each *** a fixed frequency,an increase in the oscillation amplitude leads to a phase-inclusion holding effect,i.e.,the body occupies a quasi-stationary position in one of the cells of the vertical channel,while oscillating around its average *** is also shown that the oscillating motion of a liquid column generates an averaged force acting on the body,the magnitude of which depends on the properties of the body and its position in the *** quasi-stationary position is determined by the relative density and size of the body,as well as the dimensionless *** behavior of the body as a function of the amplitude and frequency of fluid oscillation and relative size is discussed in *** findings may be used in the future to control the position of a phase inclusion and/or to strengthen mass transfer effects in a channel of variable cross section by means of fluid oscillations.

关键词： Phase inclusion axisymmetric channel variable cross section oscillations dimensionless frequency averaged force viscous boundary layer

Olefin Polymerization Behavior of Titanium(IV) Complexes with Fluorinated and Non-fluorinated Aliphatic Phenoxyimine Ligands

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Chinese Journal of Polymer Science 2024年第1期42卷 52-62,I0007页

作者： Vladislav A.Tuskaev Kasim F.Magomedov Svetlana Ch.Gagieva Dmitry A.Kurmaev Yulia V.Nelyubina Evgenii K.Golubev Maria D.Evseeva Viktor G.Vasil'ev Galina G.Nikiforova Mikhail I.Buzin Vyacheslav S.Bogdanov Boris M.Bulychev Department of Chemistry M.V.Lomonosov Moscow State UniversityMoscow 119992Russian Federation A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesMoscow119991Russian Federation Enikolopov Institute of Synthetic Polymer Materials Russian Academy of SciencesMoscow 117393Russian Federation

A series of Ti(Ⅳ) dichloride and dialkoxide com plexes with phenoxyimine ligands containing fluorinated and nonfluorinated aliphatic imine fragments have been *** molecular structures of complexes 1 and 4 were established by single-crystal X-ray diffraction *** complexes adopt a distorted octahedral coordination structure around the titanium atom and two oxygen atoms are situated in trans position while two nitrogen atoms and two outgoing ligands(Cl or iPrO) are situated in cis *** of activators(MMAO-12 and combinations Et_nAICl_(3-n)+Bu_(2)Mg) and outgoing ligand(Cl or iPrO) nature on the catalytic activity and properties of the resulting polymers was *** Ti complexes,despite the nature of the outgoing ligands(Cl or iPrO) in the presence of Al/Mg activators,was found to display a high ethylene polymerization activity in the range 1600-3830 kg_(polymer)·mol_(Ti)^(-1)·h^(-1)·atm^(-1) with a viscosity average molecular weight(M_v) value in the range 1.1×10~6-7.1×10~6 Dalton(Da).The resulting UHMWPE can be processed by a solventless method into high-strength and high-modulus oriented *** rheological characteristics of a polymer melt have been *** absence of a cross-over point did not allow to compare the values of the molecular weight distribution of polymers obtained on fluorinated and non-fluorinated pre-catalysts,however,the estimation of the entanglement density is in good agreement with the mechanical characteristics of oriented film *** activation with methylalumoxane,the activity of the com plexes decreased very significantly;however,a polymer with a molecular weight of about 12 million Da was *** the process of ethylene/octene-1 copolymerization,fluorine-containing precatalysts showed a clear advantage over non-fluorinated analogues both in activity and in comonomer content.

关键词： FI catalysts Titanium(IV) (Co)polymerization Al/Mg co-catalyst Ultra-high molecular weight polyethylene

Structural Stability of the Financial Market Model: Continuity of Superhedging Price and Model Approximation

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Journal of the Operations Research Society of China 2024年第1期12卷 215-241页

作者： Sergey N.Smirnov Faculty of Computational Mathematics and Cybernetics Lomonosov Moscow State UniversityMoscow119991Russian Federation

The present paper continues the topic of our recent paper in the same journal,aiming to show the role of structural stability in financial *** the context of financial market modeling,structural stability means that a specific“no-arbitrage”property is unaffected by small(with respect to the Pompeiu–Hausdorff metric)perturbations of the model’s *** formulate,based on our economic interpretation,a new requirement concerning“no arbitrage”properties,which we call the“uncertainty principle”.This principle in the case of no-trading constraints is equivalent to structural *** demonstrate that structural stability is essential for a correct model approximation(which is used in our numerical method for superhedging price computation).We also show that structural stability is important for the continuity of superhedging prices and discuss the sufficient conditions for this continuity.

关键词： Uncertainty Structural stability No arbitrage Continuity of superhedging price Compact-valued multifunction Financial market model approximation Trading constraints

A Note on Transition Kernels for the Most UnfavourableMixed Strategies of the Market

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Journal of the Operations Research Society of China 2024年第1期12卷 35-50页

作者： Sergey N.Smirnov Faculty of Computational Mathematics and Cybernetics Lomonosov Moscow State UniversityMoscowRussian Federation 119991

We consider a deterministic model of market evolution with trading constraints andapply a game-theoretic approach to the superhedging *** obtain sufﬁcientconditions for the game equilibrium and prove under these conditions the existenceof a Borel-measurable transition kernel describing dependence on price prehistory ofthe most unfavourable mixed strategy of the market.

关键词： Superhedging Guaranteed deterministic approach Optimal mixedstrategies of the market Borel-measurable transition kernel Game equilibrium

Linear and Non-Linear Dynamics of Inertial Waves in a Rotating Cylinder with Antiparallel Inclined Ends

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Fluid Dynamics & Materials Processing 2024年第4期20卷 787-802页

作者： Mariya Shiryaeva Mariya Subbotina Stanislav Subbotin Laboratory of Vibrational Hydromechanics Perm State Humanitarian Pedagogical UniversityPerm614000Russia The Department for Construction Engineering and Material Science Perm National Research Polytechnic UniversityPerm614990Russia

This work is devoted to the experimental study of inertial wave regimes in a non-uniform rotating cylinder with antiparallel inclined *** this setting,the cross-section of the cylinder is divided into two regions where the fluid depth increases or decreases with *** different regimes are found:inertial wave attractor,global oscillations(the cavity’s resonant modes)and regime of symmetric reflection of wave *** linear wave regimes,a steady single vortex elongated along the rotation axis is *** location of the wave’s interaction with the sloping ends determines the vortex position and the vorticity *** non-linear regimes several pairs of the triadic resonance subharmonics are detected *** instability of triadic resonance is accompanied by the periodic generation of mean vortices drifting in the azimuthal ***,the appearance frequency of the vortices is consistent with the low-frequency subharmonic of the triadic *** experimental results shed light on the mechanisms of the inertial wave interaction with zonal flow and may be useful for the development of new methods of mixing.

关键词： Rotation inertial wave attractor triadic resonance zonal flow instability

Phosphine/Benzocyclone-based Neutral Nickel Catalysts for Ethylene Polymerization and Copolymerization with Polar Monomers

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Chinese Journal of Polymer Science 2024年第2期42卷 202-212,I0007页

作者： Fei Wang Li Pan Vladislav A.Tuskaev Svetlana Ch.Gagieva Yue-Sheng Li Tianjin Key Lab of Composite&Functional Materials School of Material Science and EngineeringTianjin UniversityTianjin300072China Department of Chemistry Lomonosov Moscow State UniversityRussian Federation InstitutionLeninskie Gory 1Moscow119991Russian Federation A N Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesVavilova st.28Moscow119991Russian Federation

The efficient copolymerization of olefin with polar monomers using nickel-based catalysts presents a longstanding challenge. In this contribution, three phosphine-benzocyclone ligands and corresponding neutral nickel catalysts(Ni1: Ar = Ph;Ni2: Ar = 2-(C_(6)H_(5))C_(6)H_(4);Ni3: Ar = 2-[2',6'-(Me O)_(2)-C_(6)H3]C_(6)H_(4)) were prepared and applied for the ethylene polymerization and copolymerization with polar monomers without any cocatalyst. The bulky substituent groups in complexes Ni2 and Ni3 contributed to high catalytic activities(up to 7.24×10^(6) and 9.04×10^(6)g·mol Ni^(-1)·h^(-1), respectively), and produced high-molecular-weight polyethylene(Mw up to 545.7 k Da). Complex Ni3 exhibited high activities for ethylene polymerization at the level of 10^(6) g·mol Ni^(-1)·h^(-1) across a wide range from 30 ℃ to 120 ℃, exhibiting excellent high temperature tolerance. These nickel complexes were also effectively employed in the copolymerization of ethylene with methyl acrylate, ethyl acrylate, butyl acrylate and lauryl acrylate, producing copolymers with high molecular weights(Mw up to 80.5 k Da) and high polar monomer incorporation(up to 8.2 mol%). Microstructure analyses revealed that the introduction of large sterically hindered substituents facilitated the incorporation of polar functional units into the polymer backbone. This study demonstrates the potential of these nickel-based catalysts for efficient copolymerization of olefin with polar monomers.

关键词： Neutral nickel catalyst Ethylene polymerization Copolymerization Polar acrylate monomers

Dynamics of Low-Viscosity Liquids Interface in an Unevenly Rotating Vertical Layer

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Fluid Dynamics & Materials Processing 2024年第4期20卷 693-703页

作者： Victor Kozlov Vladimir Saidakov Nikolai Kozlov Laboratory of Vibrational Hydromechanics Perm State Humanitarian Pedagogical UniversityPerm614990Russia Institut de Mécanique des Fluides de Toulouse Toulouse INPToulouse31400France

The behavior of two immiscible low-viscosity liquids differing in density and viscosity in a vertical flat layer undergoing modulated rotation is experimentally *** layer has a circular axisymmetric *** the absence of modulation of the rotation speed,the interphase boundary has the shape of a short axisymmetric cylinder.A new effect has been discovered,under the influence of rotation speed modulation,the interface takes on a new dynamic equilibrium state.A more viscous liquid covers the end boundaries of the layer in the form of thin films,which have the shape of round spots of almost constant radius;with increasing amplitude of the velocity modulation,the wetting boundary *** is found that upon reaching the critical amplitude of oscillations,the film of a viscous liquid loses stability,and the outer edge of the wetting spot collapses and takes on a feathery *** is shown that this threshold is caused by the development of the Kelvin-Helmholtz oscillatory instability of the *** spreading radius of a spot of light viscous liquid and its stability are studied depending on the rotation rate,amplitude,and frequency of rotation speed *** discovered averaged effects are determined by different oscillatory interaction of fluids with the end-walls of the cell,due to different *** effect of films forming can find application in technological processes to intensify mass transfer at interphase boundaries.

关键词： Rotation oscillations immiscible fluids contact line interface film dynamic equilibrium Nomenclature frot

A New Generation of Rules-based Approach:Mivar-based Intelligent Planning of Robot Actions(MIPRA)and Brains for Autonomous Robots

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Machine Intelligence Research 2024年第5期21卷 919-940页

作者： Oleg Varlamov Dmitry Aladin Department of Information Processing and Management Systems RI MIVARBauman Moscow State Tchnical University(BMSTU)Moscow105005Russian Federation

To create autonomous robots,both hardware and software are *** enormous progress has already been made in the field of equipment,then robot software depends on the development of artificial *** article proposes a solution for creating“logical”brains for autonomous robots,namely,an approach for creating an intelligent robot action planner based on Mivar expert *** application of this approach provides opportunities to reduce the computational complexity of solving planning problems and the requirements for the computational characteristics of hardware platforms on which intelligent planning systems are *** theoretically and practically justify the expediency of using logically solving systems,in particular Mivar expert systems,to create intelligent planners,the MIPRA(Mivar-based Intelligent Planning of Robot Actions)planner was created to solve problems such as STRIPS for permutation cubes in the Blocks World *** planner is based on the platform for creating expert systems of the *** a result,the Mivar planner can process information about the state of the subject area based on the analysis of cause-effect relationships and an algorithm for automatically constructing logical inference(finding a solution from“Given”to“Find”).Moreover,an important feature of the MIPRA is that the system is built on the principles of a“white box”,due to which the system can explain any of its decisions and provide justification for the actions performed in the form of a retrospective of the stages of the decision-making *** preparing a set of robot actions aimed at changing control objects,expert knowledge is used,which is the basis for the functioning algorithms of the *** approach makes it possible to include an expert in the process of organizing the work of the intelligent planner and use existing knowledge about the subject *** experiments of this study have shown that instead of many hours and powerfu

关键词： Autonomous robot blocks world decision-making system expert systems intelligent planning