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Acta Metallurgica Sinica(English Letters) 2021年第3期34卷 383-389页

作者： Junke ou Shugen Wu Hao Wang Institute for Advanced Study Chengdu UniversityChengdu 610106China Zhanglan Honors College Chengdu UniversityChengdu 610106China School of Mechanical Engineering Chengdu UniversityChengdu 610106China

In this study,uniform Co_(3)O_(4) nanoparticles are prepared via a simple and facile hydrothermal synthesis without calcination *** the Co_(3)O_(4)nanomaterials are investigated as anodes for lithium ion batteries,a good electrochemical property is ***,the reversible capacity of the as-synthesized Co_(3)O_(4) nanoparticle has a significant growth from383 mAh g^(-1)of the initial cycle to 471 mAh g^(-1)of the 300 th cycle at 2 A g^(-1).Moreover,when it recovers to 50 mA g^(-1)after different current densities,a superior reversible capacity of 695 mAh g^(-1)can be *** favorable electrochemical properties will make the as-obtained Co_(3)O_(4) have a good application prospect as anode material for lithium ion batteries.

关键词： Co3O4 Hydrothermal synthesis Anode Lithium ion batteries

The low Mach number limit of non-isentropic magnetohydrodynamic equations with large temperature variations in bounded domains

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Science China Mathematics 2024年第4期67卷 787-818页

作者： Min Liang Yaobin ou School of Mathematics Renmin University of ChinaBeijing 100872China

This paper verifies the low Mach number limit of the non-isentropic compressible magnetohydrodynamic(MHD)equations with or without the magnetic diffusion in a three-dimensional bounded domain when the temperature variation is large but *** uniform estimates of strong solutions are established in a short time interval independent of the Mach number,provided that the slip boundary condition for the velocity and the Neumann boundary condition for the temperature are imposed and the initial data is well-prepared.

关键词： low Mach number limit non-isentropic compressible magnetohydrodynamic equations large temperature variations bounded domains

Infinite Conservation Laws for Nonlinear Integrable Couplings of Toda Hierarchy

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Chinese Physics Letters 2012年第9期29卷 1-4页

作者： YU fa-Jun School of Mathematics and Systematic Sciences Shenyang Normal UniversityShenyang 110034

We construct nonlinear integrable couplings of discrete soliton hierarchy,then the infinite conservation laws for the nonlinear integrable couplings of the lattice hierarchy are *** explicit application of the method proposed,the infinite conservation laws of nonlinear integrable couplings of the Toda lattice hierarchy are *** obtained integrable couplings of the Toda lattice equations and conservation laws can be used to describe the possible formation mechanisms for hydrodynamics,solid state physics and plasma physics,respectively.

关键词： integrable nonlinear lattice

Pressure distributions on prism-shaped buildings in experimentally simulated downburst

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Science China(Technological Sciences) 2014年第10期57卷 2070-2081页

作者： LI HongHai ou JinPing School of Civil Engineering Harbin Institute of Technology

Wind loading is one of the most significant factors in civil engineering that influences the structural design *** this paper,a group of manufacturing equipments for downburst simulation based on impinging jet model was developed for investigating the wind loads on structures:including the centrifugal air bellows to generate airflow,a movable platform to realize multiple locations of the building and a freely rotatable turntable to implement alterable building *** of transducers were used to measure the wind action on all surfaces of the *** pressure coefficients calculated from the observed data were utilized to evaluate the downburst wind *** distributions on three prism-shaped building models with different placements and angles were investigated to obtain the maximum wind action and mean pressure *** results showed that the maximum pressure coefficient would reach 1.0 on the top surface if the downburst just broke out over the *** that the building was in the developing field of the downburst,the top and the front surfaces would be under high wind pressure and only the back surface would endure wind *** the downdraft happens away from the prismatic building,all surfaces,except the front surface,would subject to suction with different *** was also found that the pressure coefficient on the right surface would get its negative peak at first and then go straight up to 0.6 as the angle changed from 0°to 45°and the wind pressure on the front surface would decrease slightly through the whole *** assertive results provide elemental data for structural wind-resistant design in civil engineering for the downburst-prone areas.

关键词： wind loading downburst pressure coefficient building structure impinging jet model

Modes of Shale-Gas Enrichment Controlled by Tectonic Evolution

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Acta Geologica Sinica(English Edition) 2018年第5期92卷 1934-1947页

作者： LI Chaochun ou Chenghua State-Owned Asset Management Office Southwest Petroleum University State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University

The typical characteristics of shale gas and the enrichment differences show that some shale gases are insufficiently explained by the existing continuous enrichment mode. These shale gases include the Wufeng–Longmaxi shale gas in the Jiaoshiba and Youyang Blocks, the Lewis shale gas in the San Juan Basin. Further analysis reveals three static subsystems（hydrocarbon source rock, gas reservoirs and seal formations） and four dynamic subsystems（tectonic evolution, sedimentary sequence, diagenetic evolution and hydrocarbon-generation history） in shale-gas enrichment systems. Tectonic evolution drives the dynamic operation of the whole shale-gas enrichment system. The shale-gas enrichment modes controlled by tectonic evolution are classifiable into three groups and six subgroups. Group I modes are characterized by tectonically controlled hydrocarbon source rock, and include continuous in-situ biogenic shale gas（Ⅰ_1） and continuous in-situ thermogenic shale gas（Ⅰ_2）. Group Ⅱ modes are characterized by tectonically controlled gas reservoirs, and include anticline-controlled reservoir enrichment（Ⅱ_1） and fracture-controlled reservoir enrichment（Ⅱ_2）. Group Ⅲ modes possess tectonically controlled seal formations, and include faulted leakage enrichment（Ⅲ_1） and eroded residual enrichment（Ⅲ_2）. In terms of quantity and exploitation potential, Ⅰ_1 and Ⅰ_2 are the best shale-gas enrichment modes, followed by Ⅱ_1 and Ⅱ_2. The least effective modes are Ⅲ_1 and Ⅲ_2. The categorization provides a different perspective for deep shale-gas exploration.

关键词： shale gas enrichment mode tectonic evolution hydrocarbon source gas reservoir seal formation

Conservation Laws and Self-Consistent Sources for a Super-Classical-Boussinesq Hierarchy

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Chinese Physics Letters 2011年第12期28卷 1-4页

作者： YU fa-Jun College of Maths and Systematic Science Shenyang Normal UniversityShenyang 110034

The super-classical-Boussinesq hierarchy with self-consistent sources is ***,infinitely many conservation laws for the integrable super-classical-Boussinesq hierarchy are established.

关键词： Boussinesq infinitely integrable

Spatial-temporal Analysis of Daily Air Quality Index in the Yangtze River Delta Region of China During 2014 and 2016

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Chinese Geographical Science 2019年第3期29卷 382-393页

作者： YE Lei ou Xiangjun School of Geographic Science Nantong University School of Geography Geomatics and PlanningJiangsu Normal University

Urban air pollution is a prominent problem related to the urban development in China, especially in the densely populated urban agglomerations. Therefore, scientific examination of regional variation of air quality and its dominant factors is of great importance to regional environmental management. In contrast to traditional air pollution researches which only concentrate on a single year or a single pollutant, this paper analyses spatiotemporal patterns and determinants of air quality in disparate regions based on the air quality index(AQI) of the Yangtze River Delta region(YRD) of China from 2014 to 2016. Results show that the annual average value of the AQI in the YRD region decreases from 2014 to 2016 and exhibit a basic characteristic of ‘higher in winter, lower in summer and slightly high in spring and autumn'. The attainment rate of the AQI shows an apparently spatial stratified heterogeneity, Hefei metropolitan area and Nanjing metropolitan area keeping the worst air quality. The frequency of air pollution occurring in large regions was gradually decreasing during the study period. Drawing from entropy method analysis, industrialization and urbanization represented by per capita GDP and total energy consumption were the most important factors. Furthermore, population agglomeration is a factor that cannot be ignored especially in some mega-cities. Limited to data collection, more research is needed to gain insight into the spatiotemporal pattern and influence mechanism in the future.

关键词： air quality index(AQI) spatial-temporal evolution contributing factors Yangtze River Delta(YRD)

A New Chaotic Parameters Disturbance Annealing Neural Network for Solving Global Optimization Problems

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Communications in Theoretical Physics 2003年第4期39卷 385-392页

作者： MAWei WANGZheng－ou InstituteofSystemsEngineering TianJinUniversityTranjin300072China

Since there were few chaotic neural networks applicable to the global optimization, in this paper, we propose a new neural network model ? chaotic parameters disturbance annealing (CPDA) network, which is superior to other existing neural networks, genetic algorithms, and simulated annealing algorithms in global optimization. In the present CPDA network, we add some chaotic parameters in the energy function, which make the Hopfield neural network escape from the attraction of a local minimal solution and with the parameter annealing, our model will converge to the global optimal solutions quickly and steadily. The converge ability and other characters are also analyzed in this paper. The benchmark examples show the present CPDA neural network's merits in nonlinear global optimization.

关键词： Hopfield neural network global optimization chaotic parameters disturbance simulated annealing

Heat Transfer Model with Two Heat Transfer Coefficients Along a M ultiperforated Plate-Application to Combustion Chamber Wall Cooling

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Journal of Thermal Science 2003年第4期12卷 363-366页

作者： brice Petre Eva Dorignac Jean Jacques Vullierme Laboratoire d'Etudes Thermiques U.M.R C.N.R.S 6608-ENSMA BP 40109 86961 Futuroscope Chasseneuil Cedex FRANCELaboratoire d'Etudes Thermiques U.M.R C.N.R.S 6608-ENSMA BP 40109 86961 Futuroscope Chasseneuil Cedex FRANCELaboratoire d'Etudes Thermiques U.M.R C.N.R.S 6608-ENSMA BP 40109 86961 Futuroscope Chasseneuil Cedex FRANCE

Walls' cooling of aeronautic propeller combustion chamber is performed with the injection, through the combustion chamber wall, of a part of the air coming from compressors placed upstream. Measurements of the wall thermal fields are made by infrared thermography along the injection wall. This injection wall is pierced by 9 rows of 8 holes (α=90°) in staggered configuration (p/D=s/D=6). We propose a model using two heat transfer coefficients to represent the convective exchanges. The results are non-dimensioned and presented in comparison with the case without holes. The use of this model allows us to define 4 zones. Those 4 zones exist for the 5 blowing rates.

关键词： multiperforation cooling heat transfer coefficients infrared thermography.

Online Magnetic Flux Leakage Detection System for Sucker Rod Defects Based on LabVIEW Programming

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Computers, Materials & Continua 2019年第2期58卷 529-544页

作者： ou Zhang Xueye Wei School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing100044China

Aiming at the detection of the sucker rod defects,a real-time detection system is designed using the non-destructive testing technology of magnetic flux leakage(MFL).An MFL measurement system consists of many parts,and this study focuses on the signal acquisition and processing *** of all,this paper introduces the hardware part of the acquisition system in detail,including the selection of the Hall-effect sensor,the design of the signal conditioning circuit,and the working process of the single chip computer(SCM)control serial *** on LabVIEW,a graphical programming software,the software part of the acquisition system is written,including serial port parameter configuration,detection signal recognition,original signal filtering,real-time display,data storage and ***,an experimental platform for the MFL detection is set up,and the MFL measurement is carried out on the transverse and longitudinal defects of the sucker rod *** experimental result shows that the designed acquisition and processing system has good detection performance,simple design and high flexibility.

关键词： flux leakage testing real-time detection sucker rod LabVIEW acquisition and processing