检索结果-南通市图书馆

Interaction of edge dislocations with voids in tungsten

在线全文

学校读者我要写书评

暂无评论

Tungsten 2024年第3期6卷 633-646页

作者： Arseny Kazakov Rita I.Babicheva Aleksandr Zinovev Dmitry Terentyev Kun Zhou Elena A.Korznikova Sergey V.Dmitriev Research Laboratory for Metals and Alloys under Extreme Impacts Ufa University of Science and Technology institute for Metals Superplasticity Problems of ras School of Mechanical and Aerospace Engineering Nanyang Technological University institute for Nuclear energy Technology Belgian Nuclear Research Center Technological Machines and Equipment Department Ufa State Petroleum Technological University institute of Mechanical Science Problems of ras institute of Molecule and Crystal Physics UFRC of Russian Academy of Sciences

Tungsten is widely used as a material capable of withstanding extreme operating conditions and is one of the candidates for use in fusion and Generation Ⅳ fission reactors.Atomistic modelling implemented to solve various material science problems is an indispensable approach for improving material properties.This work analyzes the interaction of an edge dislocation with a void in single-crystal tungsten with the help of molecular dynamics simulation.Two different approaches for studying the dynamics of dislocations in tungsten that differ in boundary conditions are compared.Multiple interactions of the dislocation and void at different temperatures are investigated,and based on the obtained stress-strain curves,the dislocation obstacle strength for voids having various diameters is defined.It is shown that when applied to a crystal with small voids,the model with the fixed boundary conditions returns incorrect results.Moreover,the influence of the cell size for the model with periodic boundary conditions is analyzed,and the case of a non-central interaction of a dislocation with a void is considered.The obtained results improve our understanding of the mechanical response of irradiated materials.

关键词： Tungsten Molecular dynamics method Dislocations Voids Boundary conditions

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

在线全文

同方期刊数据库

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 studied.Convection is driven by localized cooling at the center of the upper free surface and by rim heating at the bottom near the sidewall.The horizontal temperature difference in a rotating layer leads to the formation of a convective flow with a complex structure.The mean meridional circulation,consisting of three cells,provides a strongly non-uniform differential rotation.As a result of the instability of the main cyclonic zonal flow,the train of baroclinic waves appears in the upper layer.The baroclinic waves provide most of the heat transfer in the middle radii and are responsible for strong temperature and velocity fluctuations.It 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 waves.The increase in the inclination angle leads to a significant increase in the energy of the waves.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

Cobalt phthalocyanine promoted copper catalysts toward enhanced electro reduction of CO_(2)to C_(2):Synergistic catalysis or tandem catalysis?

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 energy Chemistry 2024年第5期92卷 499-507页

作者： Yan Luo Jun Yang Jundi Qin Kanghua Miao Dong Xiang Aidar Kuchkaev Dmitry Yakhvarov Chuansheng Hu Xiongwu Kang New energy Research institute School of Environment and EnergySouth China University of TechnologyHigher Education Mega CenterGuangzhou 510006GuangdongChina Guangdong University of Petrochemical Technology School of Chemical EngineeringMaoming 525000GuangdongChina Arbuzov institute of Organic and Physical Chemistry FRC Kazan Scientific Center of RASArbuzov Street 8Kazan 420088Russian Federation National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029AnhuiChina

The activity and selectivity of electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to C_(2)products on metal catalysts can be regulated by molecular surfactants.However,the mechanism behind it remains elusive and debatable.Herein,copper nanowires(Cu NWs)were fabricated and decorated with cobalt phthalocyanine(CoPc).The electronic interaction between the Cu NWs,CoPc,CO_(2) and CO_(2)RR intermediates were explored by density functional theory(DFT)calculations.It was found that the selectivity and activity of CO_(2)RR towards C_(2)products on Cu NWs were considerably enhanced from 35.2%to 69.9%by surface decoration of CoPc.DFT calculations revealed that CO_(2)RR can proceed in the interphase between Cu substrate and CoPc,and the CO_(2)RR intermediates could synergistically bond with both Cu and Co metal centre in CuNWs-CoPc,which favours the adsorption of CO_(2),CO and CO_(2)RR intermediates,thus reducing the free energy for CO-COcoupling towards C_(2)products.The synergistic interaction was further extended to phthalocyanine(Pc)and other metal phthalocyanine derivatives(MPc),where a relatively weaker synergistic interaction of COintermediates with MPc and Cu substrate and only a slight enhancement of CO_(2)RR towards C_(2) products were observed.This study demonstrates a synergistic catalysis pathway for CO_(2)RR,a novel perspective in interpreting the role of CoPc in enhancing the activity and selectivity of CO_(2)RR on Cu NWs,in contrast to the conventional tandem catalysis mechanism.

关键词： CO_(2)reduction reaction Raman spectroscopy Synergistic catalysis DFT calculation

A method to predict rockburst using temporal trend test and its application

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3期16卷 909-923页

作者： Yarong Xue Zhenlei Li Dazhao Song Xueqiu He Honglei Wang Chao Zhou Jianqiang Chen Aleksei Sobolev School of Civil and Resources Engineering University of Science and Technology BeijingBeijing100083China Zhong-an Academy of Safety Engineering Beijing100083China China energy Group Xinjiang energy Co. LtdUrumqi830027China Khabarovsk Federal Research Center of the Far Eastern Branch of the Russian Academy of Sciences(KhFRC FEB ras) 51 Turgenev StreetKhabarovsk680000Russia

Rockbursts have become a significant hazard in underground mining,underscoring the need for a robust early warning model to ensure safety management.This study presents a novel approach for rockburst prediction,integrating the Mann-Kendall trend test(MKT)and multi-indices fusion to enable real-time and quantitative assessment of rockburst hazards.The methodology employed in this study involves the development of a comprehensive precursory index library for rockbursts.The MKT is then applied to analyze the real-time trend of each index,with adherence to rockburst characterization laws serving as the warning criterion.By employing a confusion matrix,the warning effectiveness of each index is assessed,enabling index preference determination.Ultimately,the integrated rockburst hazard index Q is derived through data fusion.The results demonstrate that the proposed model achieves a warning effectiveness of 0.563 for Q,surpassing the performance of any individual index.Moreover,the model’s adaptability and scalability are enhanced through periodic updates driven by actual field monitoring data,making it suitable for complex underground working environments.By providing an efficient and accurate basis for decision-making,the proposed model holds great potential for the prevention and control of rockbursts.It offers a valuable tool for enhancing safety measures in underground mining operations.

关键词： Rockburst Microseismicity Early warning Mann-Kendall trend test Confusion matrix Multi-indices fusion

A review of solid-state lithium metal batteries through in-situ solidification

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第1期67卷 67-86页

作者： Pan Xu Zong-Yao Shuang Chen-Zi Zhao Xue Li Li-Zhen Fan Aibing Chen Haoting Chen Elena Kuzmina Elena Karaseva Vladimir Kolosnitsyn Xiaoyuan Zeng Peng Dong Yingjie Zhang Mingpei Wang Qiang Zhang Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China National and Local Joint Engineering Laboratory for Lithium-ion Batteries and Materials Preparation Technology Key Laboratory of Advanced Battery Materials of Yunnan ProvinceFaculty of Metallurgical and Energy EngineeringKunming University of Science and TechnologyKunming 650093China institute of Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China College of Chemical and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018China Ordos Carbon Neutral Research and Application Co. Ltd.Ordos City 017010China Ufa institute of Chemistry UFRC ras Ufa 450054Russia institute for Carbon Neutrality Tsinghua UniversityBeijing 100084China Shanxi Research institute for Clean energy Tsinghua UniversityTaiyuan 030032China

High-energy-density lithium metal batteries are the next-generation battery systems of choice,and replacing the flammable liquid electrolyte with a polymer solid-state electrolyte is a prominent conduct towards realizing the goal of high-safety and high-specific-energy devices.Unfortunately,the inherent intractable problems of poor solid-solid contacts between the electrode/electrolyte and the growth of Li dendrites hinder their practical applications.The in-situ solidification has demonstrated a variety of advantages in the application of polymer electrolytes and artificial interphase,including the design of integrated polymer electrolytes and asymmetric polymer electrolytes to enhance the compatibility of solid–solid contact and compatibility between various electrolytes,and the construction of artificial interphase between the Li anode and cathode to suppress the formation of Li dendrites and to enhance the high-voltage stability of polymer electrolytes.This review firstly elaborates the history of in-situ solidification for solid-state batteries,and then focuses on the synthetic methods of solidified electrolytes.Furthermore,the recent progress of in-situ solidification technology from both the design of polymer electrolytes and the construction of artificial interphase is summarized,and the importance of in-situ solidification technology in enhancing safety is emphasized.Finally,prospects,emerging challenges,and practical applications of in-situ solidification are envisioned.

关键词： in-situ solidification polymer electrolyte artificial solid electrolyte interphase rechargeable lithium metal batteries dendrite-free lithium metal anode

Optimization Problem for the Integral Model of Developing systems

在线全文

学校读者我要写书评

暂无评论

Journal of the Operations Research Society of China 2022年第4期10卷 817-833页

作者： Evgeniia Markova Inna Sidler Victor Trufanov melentiev energy systems institute of Siberian Branch of the Russian Academy of Sciences Irkutsk664033Russia

This paper addresses an integral model of development a large electric power system using the example of the Unified energy System of Russia.The model takes account of the age structure of the plants main equipment.Besides,generating equipment is divided into components depending on the types of energy resources used.The mathematical model is presented by a system of nonclassical Volterra integral equations of the first kind.One of the equations describes the balance between the total available capacity of the electric power system,commissioning of new equipment,and dismantling of obsolete one.The other equations define the shares of different types of power plants in the total composition of the electric power system equipment.Based on the considered model,we set a problem that searches the optimal lifetimes of electric power system capacities for a given demand for electricity.The optimality criterion is a functional reflecting cost of commissioning and operating the capacities.The specifics of the optimization problem are that the optimization parameter is in the lower limit of integration.An algorithm for solving of this optimal control problem numerically is developed.The influence of economic indices on the solution to the optimal control problem is studied.Calculations of the optimal development of the Unified energy System of Russia until 2050 are carried out using real-life data.

关键词： Optimization problem Integral model Lifetime

Characterization of bright betatron radiation generated by direct laser acceleration of electrons in plasma of near critical density

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Matter and Radiation at Extremes 2024年第2期9卷 26-35页

作者： J.Cikhardt M.Gyrdymov S.Zähter P.Tavana M.M.Günther N.Bukharskii N.Borisenko J.Jacoby X.F.Shen A.Pukhov N.E.Andreev O.N.Rosmej Faculty of Electrical Engineering Czech Technical University in Prague16627 Prague 6Czech Republic Goethe University FrankfurtMax-von-Laue-Straße 160438 Frankfurt am MainGermany GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany Focused energy GmbH Im Tiefen See 4564293 DarmstadtGermany National Research Nuclear University MEPhI Kashirskoe shosse 31115409 MoscowRussian Federation Lebedev Physical institute ras Leninskiy Prospekt 53119991 MoscowRussian Federation Heinrich-Heine-University Düsseldorf Universitätsstrasse 1DüsseldorfGermany Joint institute for High Temperatures RASIzhorskaya st.13Bldg.2125412 MoscowRussian Federation Moscow institute of Physics and Technology Institutskiy Pereulok 9141700 DolgoprudnyRussia

Directed x-rays produced in the interaction of sub-picosecond laser pulses of moderate relativistic intensity with plasma of near-critical density are investigated. Synchrotron-like (betatron) radiation occurs in the process of direct laser acceleration (DLA) of electrons in a relativisticlaser channel when the electrons undergo transverse betatron oscillations in self-generated quasi-static electric and magnetic fields. In anexperiment at the PHELIX laser system, high-current directed beams of DLA electrons with a mean energy ten times higher than the ponderomotive potential and maximum energy up to 100 MeV were measured at 10^(19) W/cm^(2)laser intensity. The spectrum of directed x-raysin the range of 5–60 keV was evaluated using two sets of Ross filters placed at 0°and 10°to the laser pulse propagation axis. The differential x-ray absorption method allowed for absolute measurements of the angular-dependent photon fluence. We report 10^(13) photons/sr withenergies >5 keV measured at 0°to the laser axis and a brilliance of 10^(21) photons s^(−1) mm^(−2) mrad−2(0.1%BW)−1. The angular distributionof the emission has an FWHM of 14°–16°. Thanks to the ultra-high photon fluence, point-like radiation source, and ultra-short emissiontime, DLA-based keV backlighters are promising for various applications in high-energy-density research with kilojoule petawatt-class laserfacilities.

关键词： laser acceleration critical

Environmental performance assessments of different methods of coal preparation for use in small-capacity boilers: experiment and theory

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Coal Science & Technology 2023年第5期10卷 57-71页

作者： A.N.Kozlov E.P.Maysyuk I.Yu.Ivanova melentiev energy systems institute of Siberian Branch of the Russian Academy of Sciences Irkutsk130Lermontov664033Russia

The purpose of this article is to receive environmental assessments of combustion of different types of coal fuel depending on the preparation(unscreened,size-graded,briquetted and heat-treated)in automated boilers and boilers with manual load-ing.The assessments were made on the basis of data obtained from experimental methods of coal preparation and calculated methods of determining the amount of pollutant and greenhouse gas emissions,as well as the mass of ash and slag waste.The main pollutants from coal combustion are calculated:particulate matter,benz(a)pyrene,nitrogen oxides,sulfur dioxide,carbon monoxide.Of the greenhouse gases carbon dioxide is calculated.As a result of conducted research it is shown that the simplest preliminary preparation(size-graded)of coal significantly improves combustion efficiency and environmental performance:emissions are reduced by 13%for hard coal and up to 20%for brown coal.The introduction of automated boil-ers with heat-treated coal in small boiler facilities allows to reduce emissions and ash and slag waste by 2-3 times.The best environmental indicators correspond to heat-treated lignite,which is characterized by the absence of sulfur dioxide emissions.

关键词： Coal preparation Automated and hand-fed coal boilers Environmental performance metrics

Development of a methodology for assessing the adequacy of electric power 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

Global energy Interconnection 2022年第5期5卷 543-550页

作者： Dmitry S.Krupenev Denis A.Boyarkin Dmitrii V.Iakubovskii melentiev energy systems institute of Siberian Branch of the Russian Academy of Sciences Lermontov str.130Irkutsk664033Russia

This study presents the results of a research into the developing a methodology for assessing the adequacy of advanced electric power systems characterized by the integration of various innovative technologies,which complicates their analysis.The methodology development is aimed at solving two main problems:(1)increase the adequacy of modeling the processes that occur in the electric power system and (2)enhance the computational efficiency of the adequacy assessment methodology.This study proposes a new mathematical model to minimize the power shortage and enhance the adequacy of modeling the processes.The model considers quadratic power transmission losses and network coefficients.The computational efficiency of the adequacy assessment methodology is enhanced using efficient random-number generators to form the calculated states of electric power systems and machine learning methods to assess power shortages and other reliability characteristics in the calculated states.

关键词： Electric power systems Adequacy Power shortage minimization Pseudo-and quasi-random number generation Machine learning methods.