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Journal of Iron and Steel Research International 2021年第7期28卷 799-808页

作者： zhou Pu Feng zhou yue Sun Ming Zhang Bo-quan Li Department of Instrumentation Science and Technology Jiangsu UniversityZhenjiang 212013JiangsuChina

A mathematical model based on the computational fluid dynamics method,heat and mass transfer in porous media and the unreacted shrinking core model for the oxidation reaction of an individual magnetite pellet during preheating was *** commercial software COMSOL Multiphysics was used to simulate the change in the oxidation degree of the pellet at different temperatures and oxygen concentrations,and the simulated results were compared with the exper-imental *** model considered the influence of the exothermic heat of the reaction,and the enthalpy change was added to calculate the heat released by the *** results show that the oxidation rate on the surface of the pellet is much faster than that of the inside of the *** and oxygen concentration have great influence on the pellet oxidation ***,the exothermic calculation results show that there is a non-isothermal phenomenon inside the pellet,which leads to an increase in temperature inside the single *** the preheating condition of 873-1273 K(20%oxygen content),the heat released by the pellet oxidation reaction in a chain grate is 7.8×10^(6)-10.8×10^(6) kJ/h,which is very large and needs to be considered in the magnetite pellet oxidation modelling.

关键词： Magnetite pellet Oxidation Numerical simulation Unreacted shrinking core model Computational fluid dynamics

数字经济对城乡收入差距的影响机制与空间效应

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华东经济管理 2025年第1期39卷 84-94页

作者：徐维祥石柔刚周建平浙江工业大学经济学院浙江杭州310023 浙江工业大学现代化产业体系研究院浙江杭州310023

数字经济正在逐步成为重塑中国城乡发展格局的关键力量。文章选取2011—2022年中国30个省份的样本数据,在克服内生性问题的基础上,实证分析数字经济对城乡收入差距的影响。研究发现:数字经济发展显著缩小了城乡收入差距,但这种缩减效应... 详细信息

数字经济正在逐步成为重塑中国城乡发展格局的关键力量。文章选取2011—2022年中国30个省份的样本数据,在克服内生性问题的基础上,实证分析数字经济对城乡收入差距的影响。研究发现:数字经济发展显著缩小了城乡收入差距,但这种缩减效应会受到经济发展水平的制约。异质性检验表明,较之东部地区,数字经济对西部地区城乡收入差距的影响更大。作用机制检验表明,城镇化建设和产业结构升级是数字经济影响城乡收入差距的两条重要机制。进一步研究发现,数字经济具有显著的空间溢出效应,能够对邻近地区的城乡收入差距产生积极影响。由此,研究提出固本强基、因势利导、融合创新、辐射发展的政策建议。

关键词：数字经济城乡收入差距城镇化建设产业结构升级

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Theoretical analysis for the mechanical behavior caused by an electromagnetic cycle in ITER Nb3Sn cable-in-conduit conductors

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Acta Mechanica Sinica 2018年第4期34卷 614-622页

作者： Donghua yue Xingyi Zhang You-He zhou Department of Mechanics and Engineering Sciences College of Civil Engineering and MechanicsLanzhou UniversityLanzhou 730000China Key Laboratory of Mechanicson Disaster and Environmentin Western China attached to the Ministry of Education of China Lanzhou 730000China

The central solenoid（CS）is one of the key components of the International Thermonuclear Experimental Reactor（ITER）tokamak and which is often considered as the heart of this fusion *** solenoid will be built by using Nb3Sn cablein-conduit conductors（CICC）,capable of generating a 13 T magnetic *** order to assess the performance of the Nb3Sn CICC in nearly the ITER condition,many short samples have been evaluated at the SULTAN test facility（the background magnetic field is of 10.85 T with the uniform length of 400 mm at 1%homogeneity）in Centre de Recherches en Physique des Plasma（CRPP）.It is found that the samples with pseudo-long twist pitch（including baseline specimens）show a significant degradation in the current-sharing temperature（Tcs）,while the qualification tests of all short twist pitch（STP）samples,which show no degradation versus electromagnetic cycling,even exhibits an increase of *** behavior was perfectly reproduced in the coil experiments at the central solenoid model coil（CSMC）facility last *** this paper,the complex structure of the Nb3Sn CICC would be simplified into a wire rope consisting of six petals and a cooling *** analytical formula for the Tcs behavior as a function of the axial strain of the cable is *** on this,the effects of twist pitch,axial and transverse stiffness,thermal mismatch,cycling number,magnetic distribution,etc.,on the axial strain are discussed *** calculated Tcs behavior with cycle number show consistency with the previous experimental results qualitatively and ***,we focus on the relationship between Tcs and axial strain of the cable,and we conclude that the Tcs behavior caused by electromagnetic cycles is determined by the cable axial *** the cable is in a compression situation,this compression strain and its accumulation would lead to the Tcs *** experimental observation of the Tcs enhancement in the CS STP samples should be consid

关键词： Mechanical behavior Nb3Sn cable in conduit conductor Electromagneti ccycle Sharing temperature

Effects of Wall Emissivity on Aerodynamic Heating in Scramjets

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Fluid Dynamics & Materials Processing 2020年第6期16卷 206-216页

作者： yue zhou Pengfei Ju School of Aeronautical Science and Technology Beihang UniversityBeijing100191China Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of TechnologyTianjin300384China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education(Tianjin University of Technology) Tianjin300384China

The effects of the wall emissivity on aerodynamic heating in a scramjet are *** supersonic turbulent combustion flow including radiation is solved in the framework of a decoupled strategy where the flow field is determined first and the radiation field *** particular,a finite difference method is used for solving the flow while a DOM(iscrete ordinates method)approach combined with a WSGGM(weighted sum of gray gases)model is implemented for radiative *** nonreactive turbulent channel flows are examined for a DLR hydrogen fueled scramjet changing parametrically the wall *** results indicate that the wall radiative heating rises greatly with increasing the wall *** the wall emissivity rises,the radiative source and total absorption increase,while the incident radiation decreases ***,although the radiative heating can reach a significant level,its contribution to the total aerodynamic heating is relatively limited.

关键词： Scramjet aerodynamic heating wall emissivity radiation

Preparation of Zinc-nickel-cobalt Ternary Oxide Nanosheets as Electrodes in Supercapacitors

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Chemical Research in Chinese Universities 2017年第6期33卷 939-945页

作者： shi Xue zhou Guowei Key Laboratory of Fine Chemicals in Universities of Shandong School of Chemistry and PharmaceutIcal Engineering Qilu University of Technology Jinan 250353 P. R. China

Novel zinc-nickel-cobalt ternary oxide nanosheets were successfully synthesized via an easy solvothermal method followed by calcination and were tailored to have different numbers of wrinkles by controlling the vohtrne ratio of the components in the mixed solvent. Nanosheets with more wrinkles yielded a large specific surface area（111.61 m2/g）, which improved their electrochemical properties. The resulting products were characterized using a three-electrode system in 6 mol/L KOH electrolyte solution. With unique structures, the nanosheets with more wrinkles displayed a good capacitive behavior and an excellent specific capacitance retention of 97.18% after 2000 continuous charge-discharge cycles. Considering their high electrochemical performance and simple fabrication, we proposed that these unique zinc-nickel-cobalt oxide nanosheets are promising supercapacitor electrodes for energy storage applications.

关键词： Zinc-nickel-cobalt Ternary oxide Nanosheet Wrinkle Supercapacitor

A Novel Wavelet-Homotopy Galerkin Method for Unsteady Nonlinear Wave Equations

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Advances in Applied Mathematics and Mechanics 2023年第4期15卷 964-983页

作者： yue zhou Hang Xu State Key Lab of Ocean Engineering School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The Coiflet wavelet-homotopy Galerkin method is extended to solve unsteady nonlinear wave equations for the first *** Korteweg-de Vries(KdV)equation,the Burgers equation and the Korteweg-de Vries-Burgers(KdVB)equation are examined as illustrative *** and accuracy of the proposed method are assessed in terms of relative variance and the maximum error *** results are found in good agreement with exact solutions and numerical solutions reported in previous ***,it is found that the solution accuracy is closely related to the resolution level and the convergence-control *** is also found that our proposed method is superior to the traditional homotopy analysis method when dealing with unsteady nonlinear *** is expected that this approach can be further used to solve complicated unsteady problems in the fields of science and engineering.

关键词： Coiflet wavelet homotopy analysis method wavelet-homotopy method wave equations unsteady

Alleviating the sluggish kinetics of all-solid-state batteries via cathode single-crystallization and multi-functional interface modification

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Journal of Energy Chemistry 2024年第11期98卷 123-133页

作者： Wen-Zhe Liu Xin-Hai Meng Zi-Yi zhou Qiang Zheng Ji-Lei shi yue Gong Yu-Guo Guo CAS Key Laboratory of Molecular Nanostructure and Nanotechnology Beijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China CAS Key Laboratory of Standardization and Measurement for Nanotechnology National Center for Nanoscience and TechnologyBeijing 100190China

The application of Li-rich Mn-based cathodes, the most promising candidates for high-energy-density Liion batteries, in all-solid-state batteries can further enhance the safety and stability of battery ***, the utilization of high-capacity Li-rich cathodes has been limited by sluggish kinetics and severe interfacial issues in all-solid-state batteries. Here, a multi-functional interface modification strategy involving dispersed submicron single-crystal structure and multi-functional surface modification layer obtained through in-situ interfacial chemical reactions was designed to improve the electrochemical performance of Li-rich Mn-based cathodes in all-solid-state batteries. The design of submicron single-crystal structure promotes the interface contact between the cathode particles and the solid-state electrolyte,and thus constructs a more complete ion and electron conductive network in the composite ***, the Li-gradient layer and the lithium molybdate coating layer constructed on the surface of single-crystal Li-rich particles accelerate the transport of Li ions at the interface, suppress the side reactions between cathodes and electrolyte, and inhibit the oxygen release on the cathode surface. The optimized Li-rich cathode materials exhibit excellent electrochemical performance in halide all-solid-state batteries. This study emphasizes the vital importance of reaction kinetics and interfacial stability of Lirich cathodes in all-solid-state batteries and provides a facile modification strategy to enhance the electrochemical performance of all-solid-state batteries based on Li-rich cathodes.

关键词： All-solid-state Li-ion batteries Li-rich Mn-based cathode materials Kinetics Interface Anion redox

Bayesian neural network enhancing reliability against conductance drift for memristor neural networks

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Science China(Information Sciences) 2021年第6期64卷 100-111页

作者： yue zhou Xiaofang HU Lidan WANG Shukai DUAN College of Electronics and Information Engineering Southwest University College of Artificial Intelligence Southwest University

The hardware implementation of neural networks based on memristor crossbar array provides a promising paradigm for neuromorphic computing. However, the existence of memristor conductance drift harms the reliability of the deployed neural network, which seriously hinders the practical application of memristor-based neuromorphic computing. In this paper, the impact of different types of conductance drift on the weight realized by memristors is investigated and analyzed. Then, utilizing the weight uncertainty introduced by conductance drift, we propose a weight optimization method based on the Bayesian neural network, which can greatly improve the network performance. Furthermore, an ensemble approach is proposed to enhance network reliability without increasing training cost or crossbar array resources. Finally, the effectiveness of the proposed scheme is verified through a series of experiments. In addition, the proposed scheme can be easily integrated into the implementation of neuromorphic computing, which can provide a better guarantee for its large-scale application.

关键词： conductance drift neuromorphic computing Bayesian neural network memristor crossbar array network reliability

Simulation of urban expansion using geographical similarity transition rules and neighbourhood sizes

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Journal of Geographical Sciences 2024年第7期34卷 1394-1414页

作者： LI Yinqi AN yue zhou zhou REN Hui TAN Xuelan College of Resources Hunan Agricultural UniversityChangsha410128China College of Geographical Sciences Hunan Normal UniversityChangsha410081China

Most existing cellular automata(CA)models impose strict requirements on the number and spatial distribution of *** makes it a challenge to capture spatial heterogeneity in urban dynamics and meet the modeling needs of large and complex geographic *** paper presents a CA model based on geographically optimal similarity(GOS)transition rules and similarly sized neighborhoods(SSN).By comparing the similarity in geographical configuration between samples and predicted points,the model enables a comprehensive characterization of the driving mechanism behind urban expansion and its self-organizing *** helps to mitigate the impact of sample selection and assumptions about spatial stationarity on simulation *** performance of GOS-SSN-CA simulation was tested by taking the urban expansion in the Changsha-Zhuzhou-Xiangtan urban agglomeration in China as an *** results show that GOS can derive more accurate and reliable urban transition rules with fewer samples,thereby significantly reducing spatial prediction errors compared with logistic ***,SSN selects different neighborhood sizes to represent the difference between the local self-organizing range and surrounding cells,thus further improving the simulation accuracy and restricting urban expansion ***,GOS-SSN-CA effectively characterizes the geographical similarity of urban expansion,improves simulation accuracy while constraining the urban expansion form,and enhances the practical application value of CA.

关键词： urban growth cellular automata geographic similarity model optimization spatial nonstationarity

Self-powered and self-sensing devices based on piezoelectric energy harvesting

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Science China(Technological Sciences) 2024年第6期67卷 1631-1667页

作者： CHEN GanTong ZHU yue HUANG DongMei zhou ShengXi School of Aeronautics Northwestern Polytechnical UniversityXi’an710072China School of Mathematics and Statistics Xidian UniversityXi’an710071China

Wearable devices,interactive human-machine interface equipment,wireless sensors,and small-scale cleaning devices play crucial roles in biomedical implantation,disease treatment,health monitoring,environmental purification,*** devices require a sustainable energy source to work *** the consideration of the global energy crisis and environmental pollution,researchers are exploring new,stable,and environmentally friendly methods to power these low-powered *** energy is one of the most abundant natural energy *** mechanical energy from the ambient environment or host structures into electrical energy via the direct piezoelectric effect is an efficient energy harvesting *** paper reviews the application of advanced piezoelectric materials,and small-scale self-powered and self-sensing piezoelectric devices at the cubic centimeter scale in energy harvesting and health monitoring of human,animal,machinery,roads,bridges,as well as the pollutant degradation of the *** of these devices have the capability to not only harvest mechanical energy but also enable real-time monitoring and analysis of the electrical signals generated by the direct piezoelectric effect,facilitating prompt decision-making and appropriate *** addition,potential challenges and future prospects of small-scale self-powered and self-sensing piezoelectric devices are discussed.

关键词： piezoelectric energy harvesting self-powered self-sensing wearable devices implantable devices