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Communications in Theoretical Physics 2006年第2期45卷 199-206页

作者： zhang yuan-yuan wang qi zhang hong-qing Department of Applied Mathematics Dalian University of Technology Dalian 116024 China

In this paper, a further extended Jacobi elliptic function rationM expansion method is proposed for constructing new forms of exact solutions to nonlinear partial differential equations by making a more general transformation. For illustration, we apply the method to （2＋1）-dimensionM dispersive long wave equation and successfully obtain many new doubly periodic solutions. When the modulus m→1, these sohitions degenerate as soliton solutions. The method can be also applied to other nonlinear partial differential equations.

关键词： doubly periodic solution soliton solution (2+1)-dimensional dispersive long wave equation

Negatons, Positons, and Complexiton Solutions of Higher Order for a Non-isospectral KdV Equation

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Communications in Theoretical Physics 2007年第3X期48卷 411-414页

作者： zhang yuan-yuan wang qi zhang hong-qing Department of Applied Mathematics Dalian University of Technology Dalian 116024 China

In this paper, negatons, positons, and complexiton solutions of higher order for a non-isospectral KdV equation, the KdV equation with loss and non-uniformity terms are obtained through the bilinear Baicklund transfor... 详细信息

关键词： bilinear Backlund transformation negatons positons complexiton solutions

Reduction of Carbon-bearing Pellets of Oolitic Hematite in a Shaft Furnace

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Journal of Iron and Steel Research International 2016年第3期23卷 210-219页

作者： Wei WU Jian-jun GAO Jia-qing ZENG yuan-hong qi Jian-chang wang Xi-dong zhang Metallurgical Technology Research Department Central Iron and Steel Research Institute State Key Laboratory for Advanced Iron and Steel Processes and Products Central Iron and Steel Research Institute WU Xi Zhao Shun Stainless Steel Middle Plate Co. Ltd.

When carbon-bearing pellets of oolitic hematite are treated in a shaft furnace,some problems are typically encountered：the metallization ratio of the metal pellets is low;the carbon-bearing pellets bond with each other at high temperatures;and the separation of phosphorus from iron is *** solve these problems,experiments were conducted on oolitic hematite reduction in a resistance furnace and semi-industrial test shaft *** results showed that the metallization rate reached 90% or greater under the conditions of a reduction temperature of 1 150℃,an atmosphere of simulated flue gas,and a reduction time between 1.5and *** problem of high-temperature bonding among pellets can be solved by increasing the strength of the pellets,coating their surface with a surface transfer agent and maintaining an even temperature inside the shaft *** basicity of the ore blend exerted no obvious effect on the magnetic concentrate and phosphorus *** phosphorus content in the magnetic concentrate can be further reduced by improving the grinding capacity of the ball mills used in the *** the basis of the experimental results related to oolitic hematite reduction with carbon-bearing pellets in a shaft furnace,the experimental requirements were satisfied with an average 88.27%total Fe content and 0.581% P content in the pellets.

关键词： oolitic hematite carbon-bearing pellet metallization rate high temperature bonding resistance furnace shaft furnace phosphorus separation

Quantitative Analysis of Non-Crystalline and Crystalline Solids in Blast Furnace Slag

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Journal of Iron and Steel Research International 2011年第1期18卷 8-10页

作者： wang Hai feng zhang Chun-xia qi yuan hong State Key l.aboratory ot Advanced Steel Processes and Products Central Iron and Steel Research Institute Beijing 100081 China

The granulation of blast furnace slag （BFS） with water quenching treatment has some disadvantages, such as high water consumption and difficulty for recovery heat. So developing a new dry granulation technique to treat BFS is very important. The applicability of BFS directly depends on the content of non-crystalline solids in the slag after treatment. So it is of theoretical and practical significance to analyze the content of non-crystalline solids in the slag quantitatively and simply. Metallographical test is mainly adopted to quantify the non-crystalline in BFS so far with the shortages such as complex sample, difficult determination, ect. The diffraction intensity of non-crystalline is proportionate to the content of non-crystalline in BFS, ~ray diffraction method was adopted to quantify the noncrystalline and the crystalline solids in BFS. The quantitative coefficient between the crystalline and the non-crystalline solids of BFS is 0.70 of BFS whose main composition （mass percent, %） is： CaO 38.2, SiO2 35.7, Al2Oa 16.3, and MgO 8.3. The relative error of X-ray diffractometer for quantitatively analyzing non-crystalline content of BFS is less than 1%.

关键词： blast furnace slag non crystalline crystalline quantitative analysis

Effects of metallic microstructures on fatigue fracture of Q345 steel

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Journal of Iron and Steel Research International 2020年第6期27卷 702-709页

作者： Han-qing Liu Chun-ming wang hong zhang Zhi-yong Huang qing-yuan wang qiang Chen School of Aeronautics and Astronautics Sichuan UniversityChengdu 610065SichuanChina Failure Mechanics and Engineering Disaster Prevention and Mitigation Key Laboratory of Sichuan Province Sichuan UniversityChengdu 610065SichuanChina Department of Mechanical Engineering Kyushu UniversityFukuoka 819-0395Japan School of Materials Science and Engineering Jiangxi University of Science and TechnologyGanzhou 341000JiangxiChina

Effects of high-frequency cyclic loading on the banded ferrite-pearlite steel were analyzed through crack initiation and propagation. Interfaces of ferrite and pearlite colony with a small angle deviation from the loading axis were verified to be the most potential sites to fabricate the microcracks caused by the high strain gradient. The initial crack extension inside ferrite grain was driven by shear stress in model II along the direction with a 45° angle to the loading axis. Banded pearlite colony and the high-angle grain boundaries were considered as the dominant factors that promote the fatigue resistance of the material through arousing crack deflection in short crack propagation range and crack branching in long crack propagation range to reduce the crack propagation driving force in the crack tip. P-S-N curves were used to quantify the dispersion of fatigue lifetimes and evaluate the effect of elevated volume content of pearlite colony on the fatigue performance of the material.

关键词： Ferrite-pearlite steel High-cycle fatigue Crack propagation Crack branching High-angle grain boundary P-S-N curve

Readout system for ground-based tests of BGO calorimeter of DAMPE satellite

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Nuclear Science and Techniques 2017年第10期28卷 45-50页

作者： Jun-Bin zhang Chang-qing Feng Si-yuan Ma qi wang Shu-Bin Liu qi An State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science andTechnology of ChinaHefei 230026China

A readout system for ground-based tests of the bismuth germanium oxide(BGO) calorimeter of the Dark Matter Particle Explorer satellite is described in this *** system mainly consists of a data acquisition board with a field-programmable gate array to implement the control logic, and a graphical user interface software based on LabWindows/CVI. The system has been successfully applied in a series of ground-based environmental experiments and almost all the performance tests throughout the entire manufacturing processes. These contribute significantly to the development of the BGO calorimeter before being submitted for satellite-level integration.

关键词：卫星地面测试读出系统 BGO LabWindows/CVI 现场可编程门阵列阻尼图形用户界面暗物质粒子

Bimodal microstructure – A feasible strategy for high-strength and ductile metallic materials

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Journal of Materials Science & Technology 2018年第2期34卷 257-264页

作者： Min Zha hong-Min zhang Zhi-yuan Yu Xuan-He zhang Xiang-Tao Meng Hui-yuan wang qi-Chuan Jiang State Key Laboratory of Automotive Simulation and Control Jilin University Key Laboratory of Automobile Materials of Ministry of Education & School of Materials Science and Engineering Nanling Campus Jilin University

Introducing a bimodal grain-size distribution has been demonstrated an efficient strategy for fabricating high-strength and ductile metallic materials, where fine grains provide strength, while coarse grains enable strain hardening and hence decent ductility. Over the last decades, research activities in this area have grown enormously, including interesting results onfcc Cu, Ni and Al-Mg alloys as well as steel and Fe alloys via various thermo-mechanical processing approaches. However, investigations on bimodal Mg and other hcp metals are relatively few. A brief overview of the available approaches based on thermo- mechanical processing technology in producing bimodal microstructure for various metallic materials is given, along with a summary of unusual mechanical properties achievable by bimodality, where focus is placed on the microstructure-mechanical properties and relevant mechanisms. In addition, key factors that influencing bimodal strategies, such as compositions of starting materials and processing parameters, together with the challenges this research area facing, are identified and discussed briefly.

关键词： Nanocrystalline and ultrafine-grained metals Mechanical milling Severe plastic deformation Bimodal microstructure Strength and ductility

Unsteady aerodynamics modeling for flight dynamics application

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Acta Mechanica Sinica 2012年第1期28卷 14-23页

作者： qing wang Kai-Feng He. Wei-qi qian Tian-Jiao zhang Yan-qing Cheng Kai-yuan Wu State Key Laboratory of Aerodynamics 621000 MianyangChina Computational Aerodynamics Institute China Aerodynamics Research and Development Center621000 MianyangChina Scientific Research Base of Flight Technology and Safety Civil Aviation Flight University of China618307 GuanghanChina

In view of engineering application, it is practicable to decompose the aerodynamics into three components： the static aerodynamics, the aerodynamic increment due to steady rotations, and the aerodynamic increment due to unsteady separated and vortical flow. The first and the second components can be presented in conventional forms, while the third is described using a one-order differential equation and a radial-basis-function （RBF） network. For an aircraft configuration, the mathematical models of 6- component aerodynamic coefficients are set up from the wind tunnel test data of pitch, yaw, roll, and coupled yawroll large-amplitude oscillations. The flight dynamics of an aircraft is studied by the bifurcation analysis technique in the case of quasi-steady aerodynamics and unsteady aerodynam- ics, respectively. The results show that：（1） unsteady aerodynamics has no effect upon the existence of trim points, but affects their stability; （2） unsteady aerodynamics has great effects upon the existence, stability, and amplitudes of periodic solutions; and （3） unsteady aerodynamics changes the stable regions of trim points obviously. Furthermore, the dynamic responses of the aircraft to elevator deflections are inspected. It is shown that the unsteady aerodynamics is beneficial to dynamic stability for the present aircraft. Finally, the effects of unsteady aerodynamics on the post-stall maneuverability

关键词： Unsteady aerodynamics High angle of attack Mathematical model Flight dynamics - Bifurcation analysis Post-stall maneuver

Emission Mitigation of CO_2 in Steel Industry: Current Status and Future Scenarios

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Journal of Iron and Steel Research International 2006年第6期13卷 38-42,52页

作者： HU Chang-qing CHEN Li-yun zhang Chun-xia qi yuan-hong YIN Rui-yu School of Metallurgy and Energy Hebei Polytechnic University Tangshan 063009 Hebei China State KeyLaboratory of Advanced Steel Process and Products Central Iron and Steel Research Institute Beijing 100081 China

The sustainable development against global warming is a challenge faced by societies at global level. For steel industry; the pressure of reducing CO2 emission is likely to last many years. During the past decades, the CO2 emission per ton steel has been reduced mainly due to the improvement of energy efficiency. Entering the 21st century, the steel manufacturing route must have three functions, namely, production of high performance steel products, conversion of energy, and treatment of waste. In the near future, it is expected that existing BF-BOF and EAF routes will be improved, in order to produce high performance steels, increase the use of scrap, and integrate steel industry with other industries for mitigating CO2 emission. In the long term, using carbon-free energy, reducing agents, and storing CO2 securely or converting CO2 into a harmless substance can be presumed for tremendous reduction in CO2 emission.

关键词： global warming CO2 emission steel industry emission mitigation

New Explicit Rational Solitary Wave Solutions for Discretized mKdV Lattice Equation

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Communications in Theoretical Physics 2005年第6X期44卷 1011-1014页

作者： YU Ya-Xuan wang qi zhang hong-qing Department of Applied Mathematics Dalian University of Technology Dalian 116024 China Key Laboratory of Mathematics Mechanization the Chinese Academy of Sciences Beijing 100080 China

In this letter, we study discretized mKdV lattice equation by using a new generalized ansatz. As a result,many explicit rational exact solutions, including some new solitary wave solutions, are obtained by symbolic co... 详细信息

关键词： differential-difference equations discretized mKdV lattice equation solitary wave solution rational expand method