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Flatness and Profile Integration Control Model for Tandem Cold Mills

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Journal of Iron and Steel research International 2012年第3期19卷 31-37页

作者： SHAN Xiu-ying1,2.3, LIU Hong-min1,2. JIA Chun-yu1,2. SUN Jian-liang1,2.(1. engineering research {2. of Rolling Equipment and Complete Technology of Ministry of Education, Yanshan university, Qinhuangdao 066004, Hebei, China 2. State Key Laboratory of Metastable Materials Science and Technology, Yanshan university, Qinhuangdao 066004, Hebei, China 3. Hot Tandem Rolling Factory, Jinan Iron and Steel Co Ltd, Jinan 2.0101, Shandong, China) engineering research {2. of Rolling Equipment and Complete Technology of Ministry of Education Yanshan University Qinhuangdao Hebei China State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao Hebei China Hot Tandem Rolling Factory Jinan Iron and Steel Co Ltd Jinan Shandong China

Using the effective matrix methods of flatness and profile control synthetically, the flatness and profile in- tegration control scheme for tandem cold mills is built in order to increase flatness and profile control precision of tan- dem cold mills. Corresponding control strategies are adopted for various control objectives of different stands and the coordination control strategies of various stands are given, which makes the on-line flatness control cooperate with on-line profile control and implements the parallel control of different stands. According to the measured flatness and profile data of some 1550 mm tandem cold mills, the control scheme is verified and the result indicates that the scheme has high flatness and profile control precision with steady and reliable control process. A new way and method is supplied for researching shade control of tandem cold mills.

关键词： flatness profile shape effective matrix tandem cold mill

Microstructure and formation mechanism of twins of laths of austenite with high nitrogen

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Science China(Technological Sciences) 2007年第6期50卷 755-764页

作者： WU CuiLan1,2.& LUO ChengPing2.1 center for High Resolution Electron Microscopy, College of Materials Science and engineering, Hunan {2., Changsha 410082. China 2.College of Mechanical engineering, South China {2. of Technology, Guangzhou 510641, China center for High Resolution Electron Microscopy College of Materials Science and Engineering Hunan University Changsha China College of Mechanical engineering South China University of Technology Guangzhou China

The microstructure of composite diffusion layer of the nitrided and chromized 0.2. carbon steel is investigated using TEM and EDS. It is found that laths of austenite with high nitrogen (γ N) precipitate from α-ferrite matrix in the deeper zone of the diffusion layer. These γ N laths are all twins, with their {111} twinning planes parallel to the lath axis, thus forming a characteristic "back-to-back" morphology. There are two types of γN lath. The first is a genuinely {111} twin, and γ N and α keep the accurate K-S relationship, and each γ N and α form a sharp and smooth γ N/α inter- face of {335}γN//{341}α, namely habit plane {335}fcc. The second is a pseudo-twin, with micro-twins {111} or faults formed within the two twin components. Localized lattice deformation (relaxation) seems to have occurred at the interfaces of the second type of γ N due to the formation of micro-twins or faults within the twin components. These micro-twins or faults make the orientation relationship (OR) between each of the γN and the α-matrix deviate from the accurate K-S OR, and the OR between two γ N twin components deviate from the genuine {111} twin relation- ship. In addition, the γ N/α interface of the second type of γ N is not as sharp or smooth as that of the first one.

关键词： austenite containing nitrogen, twins, steel 2., nitriding, composite chromizing

Integrating MODFLOW and GIS technologies for assessing impacts of irrigation management and groundwater use in the Hetao Irrigation District,Yellow River basin

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Science China(Technological Sciences) 2009年第11期52卷 3257-3263页

作者： XU Xu1,2. HUANG GuanHua1,2.& QU ZhongYi3 1 center for Agriculture Water research, China Agricultural {2., Beijing 100083, China 2.Chinese-Israeli International center for research and Training in Agriculture, China Agricultural {2., Beijing 100083, China 3 Water Conservancy and Civil engineering College, Inner Mongolia Agricultural {2., Hohhot 010018, China center for Agriculture Water research China Agricultural University Beijing China Chinese-Israeli International center for {2. and Training in Agriculture China Agricultural University Beijing China Water Conservancy and Civil engineering College Inner Mongolia Agricultural University Hohhot China

Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district. Application of water-saving practices (WSPs) is required for the sustainable agricultural development. The human activities including WSPs and increase of groundwater abstraction can lower down the groundwater table, which is helpful to the salinity control. Meanwhile, an excessively large groundwater table depth may result in negative impact on crop growth and fragile ecological environment. In this paper, the Jiefangzha irrigation system in Hetao irrigation district was selected as a typical area, a groundwater flow model based on ArcInfo Geographic Information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area. The preand post-processing of model data was performed efficiently by using the available GIS tools. The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for Application (VBA). The model was calibrated and validated with independent data sets. Application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

关键词： groundwater flow modeling MODFLOW GIS water-saving practices irrigation district

Effects of Multiple Plastic Deformations on Microstruc-ture and Mechanical Properties of 7A04-T6

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稀有金属材料与工程 2011年第S3期40卷 69-72页

作者： Zhang Zhimin1,2. Yu Jianmin1, Wang Qiang2. Zhang Xing 2.1 engineering research {2. of Magnesium-base Material Processing Technology, Ministry of Education, Taiyuan 030051, China 2.North university of China, Taiyuan 030051, China Minist Educ Engn Res Ctr Magnesium Base Mat Proc Technol Taiyuan 030051 Peoples R China N Univ China Taiyuan 030051 Peoples R China

The influences of multiple plastic deformations on microstructure and mechanical properties of 7A04-T6 alloy by isothermal compression experiments in different passes deformation on the 6300 kN extrusion press. The experimental results showed that the strength and elongation of 7A04-T6 alloy were increased firstly and then decreased as the deformation pass increases at above 400 ℃. The grains of 7A04-T6 alloy was refined firstly and then grow, the grain was become refinement after four deformations under this experimental conditions. The second phase η (MgZn2. in the matrix would precipitate after solution, precipitation strengthening taking place. It is obvious that the number of second phase which dissolve into the matrix will increase as the deformation pass increasing. So the tensile strength reached the highest after four deformations, is 590.9 MPa, yield strength is 532.5 MPa, and elongation is 12.4%. After four deformations of 7A04-T6 alloy, tensile fracture surface of samples was composed of the deep and uniform dimples, belonging to ductile fracture. Therefore, 7A04-T6 alloy has better comprehensive mechanical properties after four deformations.

关键词： 7A04 high-strength aluminum alloy multiple deformations T6 heat treatment

Analysis of the carbon source for diamond crystal growth

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Chinese Science Bulletin 2008年第6期53卷 937-942页

作者： LI Li1,2. XU Bin2.3 & LI MuSen1,2.1 School of Materials Science & engineering, Shandong university, Jinan 2.0061, China 2.Shandong engineering research center for Super Hard Materials, Zoucheng 2.3500, China 3 School of Materials Science & engineering, Shandong Jianzhu university, Jinan 2.0101, China School of Materials Science & engineering Shandong University Jinan China Shandong engineering research {2. for Super Hard Materials Zoucheng China School of Materials Science & engineering Shandong Jianzhu University Jinan China

The lattice constants of diamond and graphite at high pressure and high temperature (HPHT) were calculated on the basis of linear expansion coefficient and elastic constant. According to the empirical electron theory of solids and molecules (EET), the valence electron structures (VESs) of diamond, graphite crystal and their common planes were calculated. The relationship between diamond and graphite structure was analyzed based on the boundary condition of the improved Thomas-Fermi-Dirac theory by Cheng (TFDC). It was found that the electron densities of common planes in graphite were not continuous with those of planes in diamond at the first order of approximation. The results show that during the course of diamond single crystal growth at HPHT with metal catalyst, the carbon sources forming diamond structure do not come from the graphite structure directly. The diamond growth mechanism was discussed from the viewpoint of valence electron structure.

关键词：钻石晶体生长石墨碳源价电子结构

Speciation of the elements and compositions on the surfaces of dust storm particles:The evidence for the coupling of iron with sulfur in aerosol during the long-range transport

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Chinese Science Bulletin 2005年第8期50卷 738-744页

作者： ZHANG Xingying1,2. ZHUANG Guoshun1,2.3, CHEN Jianmin2.& XUE Huaxin2.1. center for Atmospheric Environment Study, Department of Chemistry, Beijing Normal university, Beijing 100875, China 2. center for Atmospheric Chemistry Study, Department of Environ- mental Science and engineering, Fudan university, Shanghai 2.0433, China 3. LAPC/NZC, Institute of Atmospheric Physics, NZC/LAPC, Chinese Academy of Sciences, Beijing 10002., China center for Atmospheric Environment Study Department of Chemistry Beijing Normal University Beijing 100875 China center for Atmospheric Chemistry Study Department of Environmental Science and Engineering Fudan University Shanghai 200433 China LAPC/NZC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The speciation of the elements on the surface of the particles collected during dust storm and non-dust storm in Beijing and Inner Mongolia was studied by XPS. The ma- jor species of iron on the surface were oxides, sulfate, silicate, FeOOH and minor part sorbed on SiO2.Al2.3. Sulfate is the dominant species of sulfur on the surface. SiO2.and Al2.3 are the main components of Si and Al on the surface respectively. One of the most important findings was that the Fe(II) (FeS and FeSO4) produced could account for up to 44.3% and 45.6% of the total Fe on the surface in the aerosol sample collected at that night and next day of the “peak” time of the dust storm occurring on March 2., 2.02. while Fe2.SO4)3, one of the Fe(III) species on the surface decreased from 67.1% to 49.5% and 48.0% respectively. Both S and Fe en- riched on the surface of aerosol particles. Fe(II) accounted for 1.3%?5.3% of total Fe in bulk aerosol samples during dust storm. These results provided strong evidence to sup- port the hypothesis of the coupling between iron and sulfur in aerosols during the long-range transport, which would have important impact on the global biogeochemical cycle.

关键词：物种形成原理 XPS 大气悬浮物 Fe-S结合粒子集合

Dam risk assistant analysis system design

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Science China(Technological Sciences) 2008年第S2期51卷 101-109页

作者： HE XianFeng1,2.3,GU ChongShi3,4,WU ZhongRu3,4 & SU HuaiZhi3,4 1 Yellow River Institute of Hydraulic research,Zhengzhou 450003,China 2.Embankment Security Defect Prevention and Control engineering research center of MWR,Zhengzhou 45000,China 3 College of Water Resources and Hydropower engineering,Hohai university,Nanjing 2.0098,China 4 national engineering research center of Water Resources Efficient Utilization and engineering Safety,Hohai university,Nanjing 2.0098,China Yellow River Institute of Hydraulic research Zhengzhou China Embankment Security Defect Prevention and Control engineering research {2. of MWR Zhengzhou China College of Water Resources and Hydropower engineering Hohai University Nanjing China national engineering {2. center of Water Resources Efficient Utilization and engineering Safety Hohai University Nanjing China

In order to reduce the labor intensity and task difficulty of dam risk analysis and to meet the actual requirement of dam risk analysis,it is necessary to establish a dam risk assistant analysis *** program structure and the implementation ways of the dam risk assistant analysis system are analyzed,and a procedural framework with "three-tier and multi-database" structure and "level structure" is *** concept of dam risk assessment system modular development is proposed and the coupled mode of function module and data is ***,the dam risk assistant analysis system is developed using Delphi visual programming language.

关键词： dam risk risk analysis assistant analysis system

Adsorption of surfactants onto acrylic ester resins with different pore size distribution

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Science China Chemistry 2006年第5期49卷 445-453页

作者： YANG Weiben1,2.3,LI Aimin1,3,CAI Jianguo1,3,MENG Guanhua1,3 & ZHANG Quanxing1,3 1. State Key Laboratory of Pollution Control and Resource Reuse,School of the Environment,Nanjing university,Nanjing 2.0093,China 2. Nanjing College of Chemical Technology,Nanjing 2.0048,China 3. Jiangsu engineering & Technology {2. center for Organic Toxicant Control and Resource Reuse,Nanjing 2.0038,China State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing China Nanjing College of Chemical Technology Nanjing China Jiangsu engineering & Technology research {2. for Organic Toxicant Control and Resource Reuse Nanjing China

In this study, a series of acrylic ester resins with different pore size distribution were prepared successfully by varying the type and the amount of pore-forming agents. In order to inves-tigate the adsorption behavior and mechanism of surfactants on acrylic ester resins, three kinds of surfactants were utilized as adsorbates that were sodium 6-dodecyl benzenesulfonate (6-NaDBS), sodium 1-dodecyl benzene sulfonate (1-NaDBS) and sodium 1-dodecyl sulfonate, respectively. It was observed that the surface area was available in a particular pore size and an appropriate pore size of resins appeared to be more important for the adsorption of surfactants. As compared to commercial acrylic ester resins XAD-7 and HP2.G, 50# and 38# resins exhibited more excellent adsorption properties toward 1-NaDBS and 6-NaDBS. The experimental equilibrium data were fitted to the Langmuir, and double-Langmuir models. Two models provided very good fittings for all resins over the temperature range studied. The investigation indicated that electrostatic attraction and hydrogen bond between resins and surfactants were the main forces and had an obvious effect on adsorption proc-ess.

关键词： acrylic ester resin, surfactant, adsorption, pore size distribution, isotherm.

NEURAL NETWORK APPROACH TO SURFACE BLENDING BASED ON DIGITIZED POINTS

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Chinese Journal of Mechanical engineering 2001年第4期14卷 322-324页

作者： Xing Yuan,Jiang Hongfan,Wang Yu (national Die & Mold CAD engineering {2. center, Shanghai Jiaotong university) 上海交通大学模具CAD国家工程研究中心上海

A neural network approach is employed to deal with blending problem with surface construction based on digitized points, and some related computational cases are presented. Compared with the NURBS method, this neural network based approach doesn't need the complex formula derivation as long as a limited number of offset points are got, and its accuracy can meet the general engineering needs.

关键词： Surface Blending Neural networks