检索结果-南通市图书馆

Friction 2024年第5期12卷 1042-1056页

作者： Anastasiya A.YAKOVENKO Irina G.GORYACHEVA Ishlinsky institute for Problems in Mechanics ras Moscow119526Russia

The contact of a rigid body with nominally flat rough surface and an elastic half-space is *** solve the contact problem,the Greenwood-Williamson statistical model and the localization principle are *** developed contact model allows us to investigate the surface approach and the real contact area with taking into account the asperities *** is shown that the mutual influence of asperities changes not only contact characteristics at the macroscale,but also the contact pressure distribution at the *** follows from the results,the inclusion in the contact model of the effect of the mutual influence of asperities is especially significant for studying the real contact area,as well as the contact characteristics at high applied *** results calculated according to the proposed approach are in a good agreement with the experimentally observed effects,i.e.,the real contact area saturation and the additional compliance exhaustion.

关键词： surface roughness elasticity Greenwood-Williamson model localization principle asperity interaction

Unravelling-based (auto)control of back-action in atomic Bose–Einstein condensate

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of physics 2024年第4期19卷 287-295页

作者： V.A.Tomilin L.V.Il’ichov institute of Automation and Electrometry SB ras 630090 NovosibirskRussia

We present a novel feedback control method for quantum *** does not affect the controlled system ***,it controls the unravelling of the quantum channel of interaction between the system and its *** interaction can be represented as a history of *** their informational content is changed,their back-action on the system is also *** action is trigged by the events,thus granting the system the degree of control over its own *** efficiency of the proposed scheme is demonstrated on the example of two-mode atomic Bose-Einstein condensate,with one of its modes subject to phase-contrast imaging in a Mach–Zehnder *** histories of photocounts in the output channels of the interferometer are used for *** capabilities of state engineering are studied for different settings of the feedback loop and different numbers of events in the recorded histories.

关键词： quantum feedback control quantum measurements twomode Bose-Einstein condensates

Study of asphaltene reaggregation in toluene/heptane mixture by dynamic and static light scattering

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Research 2024年第1期9卷 48-54页

作者： Vladimir N.Kuryakov Oil and Gas Research institute of ras(OGRI ras) Gubkina Str.3119333MoscowRussian Federation

This paper presents the study of the effect of multiple ultrasonic impacts on submicron asphaltene aggregates in a toluene/heptane solution,conducted with dynamic light scattering *** objects of the study were four samples of asphaltenes obtained from four different *** all samples,the change in the average size of the asphaltene submicron aggregates with time was measured after the addition of a precipitant(heptane)to a solution of asphaltenes in toluene at an amount above the threshold *** aggregates formed in solution after the addition of the precipitant and were subjected to ultrasonic treatment,which led to the destruction of the asphaltene *** of destroyed asphaltenes was *** kinetics of this aggregation were similar to the kinetics of aggregation of asphaltenes after the addition of a *** iterations of asphaltene aggregate destruction in the sample led to a significant change in the kinetics of aggregation:the growth of aggregates slowed and stabilized at a size of approximately 200 nm and 30 nm for the different studied samples.

关键词： Asphaltenes Aggregation Sonication Dynamic light scattering Re-aggregation Colloidal stability Resins

Interatomic Interaction Models for Magnetic Materials:Recent Advances

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2024年第6期41卷 54-66页

作者： Tatiana S.Kostiuchenko Alexander V.Shapeev Ivan S.Novikov Emanuel institute of Biochemical Physics ras 4 Kosygin StreetMoscow119334Russian Federation Independent investigator

Atomistic modeling is a widely employed theoretical method of computational materials *** has found particular utility in the study of magnetic ***,magnetic empirical interatomic potentials or spinpolarized density functional theory(DFT)served as the primary models for describing interatomic interactions in atomistic simulations of magnetic ***,in recent years,a new class of interatomic potentials known as magnetic machine-learning interatomic potentials(magnetic MLIPs)has *** MLIPs combine the computational efficiency,in terms of CPU time,of empirical potentials with the accuracy of DFT *** this review,our focus lies on providing a comprehensive summary of the interatomic interaction models developed specifically for investigating magnetic *** also delve into the various problem classes to which these models can be ***,we offer insights into the future prospects of interatomic interaction model development for the exploration of magnetic materials.

关键词： materials interaction empirical

Changes in filtration and capacitance properties of highly porous reservoir in underground gas storage:CT-based and geomechanical modeling

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 2982-2995页

作者： Valerii Khimulia Vladimir Karev Yury Kovalenko Svyatoslav Barkov Ishlinsky institute for Problems in Mechanics ras Moscow119526Russia

The paper presents the results of comprehensive studies of filtration and capacitance properties of highly porous reservoir rocks of the aquifer of an underground gas storage *** geomechanical part of the research included studying the dependence of rock permeability on the stress-strain state in the vicinity of the wells,and physical modeling of the implementation of the method of increasing the permeability of the wellbore zone-the method of directional unloading of the *** digital part of the research included computed tomography(CT)-based computer analysis of the internal structure,pore space characteristics,and filtration properties before and after the *** to the results of physical modeling of deformation and filtration processes,it is found that the permeability of rocks before fracture depends on the stress-strain state insignificantly,and this influence is ***,when downhole pressure reaches 7-8 MPa,macrocracks in the rock begin to grow,accompanied by irreversible permeability ***,geodesic tortuosity and permeability values were obtained based on digital studies and numerical modeling.A weak degree of transversal anisotropy of the filtration properties of rocks was *** on the analysis of pore size distribution,pressure field and flow velocities,high homogeneity and connectivity of the rock pore space is *** absence of pronounced changes in pore space characteristics and pore permeability after non-uniform triaxial loading rocks was *** the basis of geometrical analysis of pore space,the reasons for weak permeability anisotropy were *** filtration-capacitance properties obtained from the digital analysis showed very good agreement with the results of field and laboratory *** physical modeling has confirmed the efficiency of application of the directional unloading method for the reservoir under *** necessary parameters of its application were calcu

关键词： Permeability anisotropy Reservoir porosity Rocks computed tomography(CT) Digital core analysis Filtration flow numerical modeling

Age and geochemical evolution of granite magmatism in Olkhon region from Caledonian syncollisional ore-free granite to the rare metal granite and pegmatite of Middle Paleozoic intraplate setting

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Geology 2024年第1期7卷 63-79页

作者： Viktor Antipin Valentina Makrygina Larisa Kushch Nataliya Sheptyakova Vinogradov institute of Geochemistry SB RAS664033 IrkutskRussia

The detailed description of two granite complexes in the Olkhon subterrane is *** Early Paleozoic Sharanur complex was formed by granitization of gneisses of the Olkhon *** includes migmatites,granite-gneisses,granites and pegmatites of normal alkalinity;they belong to the type of syncollisional *** Middle Paleozoic Aya granite complex includes mother Aya massif of amazonite-bearing granites and several types of rare-metal *** have elevated alkalinity,low of Ba,Sr,and high LILE and HFSE elements *** Aya pegmatites lie in northwest cracks of stretching and associated with the rise of the territory under the influence of the North Asian *** cracks and pegmatites mark the beginning of a new intraplate geodynamic *** geochemical types are distinguished among the pegmatites of this *** are amazonite pegmatites of Li-F type with Ta mineralization and complex type pegmatite with Be-Rb-Nb-Ta and Li-F mineralization(the Ilixin vein).The Tashkiney pegmatite vein is similar to Ilixin,but lies in the gneisses of the Olkhon *** shows high concentrations of Be,Nb,Ta,as well as W,Sn,but lacks Li and F,due to a greater depth and higher temperature of the melt crystallization of this pegmatite.

关键词： Pegmatite Geochemistry Submantle plume Magmatism Caledonian collision Middle Paleozoic intraplate setting Be-Rb-Nb-Ta-Li-F mineralization Olkhon region Russia

Influence of Bottom Inclination on the Flow Structure in a Rotating Convective Layer

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Fluid Dynamics & Materials Processing 2024年第4期20卷 739-748页

作者： Andrei Vasiliev Andrei Sukhanovskii Elena Popova Laboratory of Turbulence Institute of Continuous Media Mechanics UB RASPerm614013Russia

The formation of convective flows in a rotating cylindrical layer with an inclined bottom and free surface is *** is driven by localized cooling at the center of the upper free surface and by rim heating at the bottom near the *** horizontal temperature difference in a rotating layer leads to the formation of a convective flow with a complex *** mean meridional circulation,consisting of three cells,provides a strongly non-uniform differential *** a result of the instability of the main cyclonic zonal flow,the train of baroclinic waves appears in the upper *** baroclinic waves provide most of the heat transfer in the middle radii and are responsible for strong temperature and velocity *** is shown that the inclination of the bottom is a crucial factor for the structure of the convective cells and the dynamics of the baroclinic *** increase in the inclination angle leads to a significant increase in the energy of the *** obtained results may be important for heat and mass transfer in various geophysical and industrial systems,including transport of various additives and impurities in rotating crucibles,and crystallization processes.

关键词： Laboratory modeling global atmospheric circulation baroclinic waves beta-effect

Convection and Stratification of Temperature and Concentration

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Fluid Dynamics & Materials Processing 2024年第6期20卷 1351-1364页

作者： Alexey Fedyushkin Laboratory of Complex Fluid Mechanics Ishlinsky Institute for Problems in Mechanics RASMoscow119526Russia

This study is devoted to an analysis of natural convection and the emergence of delamination in an incompressible fluid encapsulated in a closed region heated from the ***,medium and intensive modes of stationary laminar thermal and thermo-concentration convection are *** is shown that nonlinear flow features can radically change the flow structure and characteristics of heat and mass ***,the temperature and concentration segregation in the center of the square region display a non-monotonic dependence on the Grashof number(flow intensity).The formation of a nonstationary periodic structure of thermal convection in boundary layers and in the core of a convective flow in the closed region is also *** of the formation of countercurrents inside the region with the direction opposite to the main convective flow are ***,the influence of vertical and horizontal vibrations on oscillatory convection is analyzed in detail.

关键词： Natural convection stratification segregation numerical simulation vibrations

Architecture of Graphics System with 3D Acceleration Support for Embedded Operating Systems

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2024年第3期29卷 863-873页

作者： Alexander Giatsintov Kirill Mamrosenko Pavel Bazhenov Center of Visualization and Sattelite Information Technologies Scientific Research Institute for System Analysis of the Russian Academy of Sciences(SRISA RAS)Moscow 117218Russia

An increasing number of tasks now require the use of hardware accelerators to reduce the time required for computation and display the computational *** paper presents a new graphics system architecture for operating systems(OSs)with microkernel architecture,including real-time *** proposed system architecture provides capabilities for displaying graphical images on various information display devices and for accelerating graphical operations on *** architecture of the graphics system uses a concept of allocators to manage system and video memory,provides an abstraction of memory operations with a single interface for video memory management,and simplifies memory handling where incorrect operation is the cause of many failures.A comparison between the performance of a real-time OS and Linux OS implementing the graphics system using the example of a glmark2 benchmark is presented,thereby the superiority of the proposed architecture in several scenarios is demonstrated.

关键词： real-time operating system(RTOS) graphics system rendering system architecture operatingsystem visualization system programming

Major- and Trace- Element Chemistry of Clinopyroxene and Amphibole from High-Mg Diorite in Chelyabinsk Massif(Urals): Insights into Petrogenesis and Magma Source Constraints

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Earth Science 2024年

作者： Tatiana Osipova Gennadiy Kallistov Maria Chervyakovskaya Vasiliy Chervyakovskiy Zavaritsky institute of Geology and Geochemistry Ural Branch of ras

Field- and petrographic investigations， together with microanalytical major- and trace-element studies， were carried out on clinopyroxene and amphibole from high-Mg diorite in the subduction-related Chelyabinsk granitic massif to understand its petrogenesis and source. The clinopyroxene composition (high Mg#， Cr-content， sum of REE and Ti/Eu ratio; depletion in HREE; negative Eu-anomaly) indicates that it formed from a reduced melt derived from a mantle source metasomatized by fluids/melts having crustal affinity. Melt compositions in equilibrium with clinopyroxene and amphibole were calculated using solid/liquid partition coefficients. The high Nb/Y and Zr/Y ratio values of a liquid simulated from clinopyroxene， which appears to have very similar characteristics to sanukitoid melts， indicate a low degree of melting of the mantle source. Melt simulated from amphibole is more evolved and more felsic (dacitic). It displays a geochemical “amphibole fractionation” signature， indicating the peritectic transformation of clinopyroxene to amphibole in the lower crust. Rock textures and major element mineral compositions suggest that further amphibole was precipitated directly from the melt in the middle crust. The results show that the Chelyabinsk high-Mg diorite was probably formed as a cumulate from sanukitoid-like melt during its ascent and cooling below dacitic liquidus inside the amphibole stability field.

关键词：