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Equilibrium Phase Constituents and Discontinuous Precipitation Behavior of Al-Zn-Cu Alloy with Symmetrical Composition

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Journal of materials Science & technology 2003年第5期19卷 419-421页

作者： Shiming HAO, Yuping REN, Hua DING, Dapeng WANG, Gang ZHAO and Hongxiao LIschool of materials and Metallurgy, Northeastern university, shenyang 110004, china Sch. of Mat. and Metall. Northeastern Univ. Shenyang 110004 China

Through microstructure observation and X-ray diffraction analysis, the equilibrium phase constituents of Al-Zn alloy that contains 2 at. pct Cu at room temperature have been determined as Al-based solid solution (α), Zn-based solid solution and AI4Cu3Zn phase (T'-phase), which are different from a phase, Zn phase and CuZn4 phase originally believed. It is determined that the products of discontinuous precipitation transformation below 277℃ are not the equilibrium phase constituents, but the metastable phases made up of a phase, Zn phase and CuZn4 phase. The phase constituents after discontinuous precipitation of AIZn-2Cu alloy would transform to the ones in equilibrium status: Al-based solid solution (α) in fcc structure, Zn-based solid solution in hcp structure and AI4Cu3Zn phase (T'-phase) ultimately through plastic deformation at room temperature and re-heating treatment below 277℃.

关键词： Al-Zn-Cu alloy Discontinuous precipitation Phase constituents Deformation

Effect of Preparation Methods on Mechanical Properties of PVA/HA Composite Hydrogel

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Journal of Bionic Engineering 2010年第3期7卷 235-243页

作者： Dekun Zhang~1, Junjie Duan~1, Dagang Wang~2, Shirong Ge~2 1. school of materials Science and Engineering, china university of Mining and technology Xuzhou 221116, P. R. china 2. school of Mechanical and Electrical Engineering, china university of Mining and technology, Xuzhou 221116, P. R. china [a] school of materials Science Engineering China University of Mining technology Xuzhou 221116 P. R. China [b] School of Mechanical Electrical Engineering China University of Mining technology Xuzhou 221116 P. R. China

Poly(vinyl alcohol) (PVA)/hydroxyapatite (HA) composite hydrogel specimens were prepared with 15% PVA and 1%,2%, 3%, 4% and 5% HA by repeated freezing-thawing. The tests of static and dynamic mechanical properties were carried out todiscuss the influence of different contents of HA and freezing-thawing cycles on the mechanical properties of PVA/HA compositehydrogel. The results of static mechanical tests showed that the PVA/HA composite hydrogel with 3% HA and ninefreezing-thawing cycles had excellent stress relaxation properties, higher relaxation ratio, lower stress equilibrium value andpresented better properties of creep and recovery. The results of dynamic mechanical test showed that the PVA/HA compositehydrogel with nine freezing-thawing cycles had higher storage modulus and loss modulus, so was the PVA/HA compositehydrogel with 3% HA.

关键词： composite hydrogel HA contents freezing-thawing cycles static properties dynamic properties

Detection of CD2 expression in chicken hematogenic embryo yolk sac lymphoid cells prior to thymus genesis

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Progress in Natural Science:materials International 2008年第12期18卷 1589-1594页

作者： Dongyu Zhou~a Jigui Wang~b Weiquan Liu~b Rongxiu Liu~c Yuehu Pei~a a College of Traditional Chinese Materia Medica,shenyang Pharmaceutical university,shenyang 110016,china b College of Biological Sciences,china Agricultural university,Beijing 100094,china c liaoning Tianhe Biotechnology Co.Ltd,Room 1203,100-1 Dongbinhe Road,shenyang District,shenyang 110016,china [a]College of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China [b]College of Biological Sciences China Agricultural University Beijing 100094 China [c]liaoning Tianhe Biotechnology Co. Ltd Room 1203 100-1 Dongbinhe Road Shenyang District Shenyang 110016 China

Lymphoid mononuclear cells from chick embryos at stage 16 were collected prior to fetal liver and thymus genesis to study the dif- ferentiation and function of the hematogenic yolk sac and to detect whether CD2 occurs on the surface of lymphoid mononuclear cells. The phenotype and functional activity of the cell surface protein E receptor and the ultrastructure of embryonic E~+ cells were compared with those of mature T *** results indicate 99.36% homology between the E receptors of embryonic lymphocytes and mature T *** similarities,including molecular distribution,motivation,the ability to form an erythrocyte rosette,the structure of the receptor-ligand complex,and the conformation of the signal channel,were detected between embryonic lymphocytes and mature CD2-expressing T *** results indicate that CD2 is already expressed prior to fetal liver and thymus genesis and that its expression is not dependent on the thymic microenvironment.

关键词： CD2 Chicken embryo Hematogenic yolk sac

Effects of Pre-Ageing Treatment on Subsequent Artificial Ageing Characteristics of an Al-1.01Mg-0.68Si-1.78Cu Alloy

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Journal of materials Science & technology 2010年第2期26卷 141-145页

作者： Lizi He , Haitao Zhang and Jianzhong Cui Key Lab of Electromagnetic Processing of materials, Ministry of Education, Northeastern university, shenyang 110004, china [a] Key Lab of Electromagnetic Processing of materials Ministry of Education Northeastern university shenyang 110004 china

The influences of pre-ageing temperature and natural ageing time on subsequent artificial age hardening behavior and precipitation sequence of new type Al-1.01Mg-0.O8Si-l.78Cu alloy were investigated by hardness test, differential scanning calorimetry （DSC） test and transmission electronic microscopy （TEM） observations. When pre-ageing temperature is 20℃ （natural ageing）, the peak hardness of subsequent artificial aged alloy is lower than that of T6 treated alloy （negative effect）, while a positive effect appears when pre-ageing temperature is above 80℃. The size of needlelike /3-precipitate in subsequent artificial aged alloy is much coarser when pre-ageing temperature is 20℃, which causes a decrease in peak-hardness. The positive effect occurs again when natural ageing time is longer than 3 weeks. There are seven exothermic peaks in DSC curve of as-quenched alloy, while the number and height of exothermic peak decrease with increasing pre-ageing temperature and natural ageing time.

关键词： Al-Mg-Si-Cu alloy Pre-ageing treatment Age hardening Differential scanning calorimetry (DSC) curve

Ferroelectric properties of Bi_(3.4)Ho_(0.6)Ti_3O_(12) thin films prepared by sol-gel method

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Science china(Technological Sciences) 2008年第9期51卷 1439-1444页

作者： FU ChengJu1, HUANG ZhiXiong1, LI Jie2 & GUO DongYun3 1 school of materials Science and technology, Wuhan university of technology, Wuhan 430070, china 2.school of Mechanical Engineering, Chongqing university of Science and technology, Chongqing 400050, china 3 Department of Physics, Wuhan university, Wuhan 430072, china school of materials Science and technology Wuhan University of Technology Wuhan 430070 China school of Mechanical Engineering Chongqing University of Science and Technology Chongqing 400050 China Department of Physics Wuhan University Wuhan 430072 China

We have prepared the Ho-substituted bismuth titanate (Bi3.4Ho0.6Ti3O12, BHT) thin films on Pt/Ti/SiO2/Si substrates using sol-gel method. The crystal structure and morphology of the films were characterized using X-ray diffraction and atomic force microscopy. The BHT film shows a single phase of Bi-layered Aurivillius structure and dense microstructure. The 2Pr and 2Ec of the 600-nm-thick BHT film were 38.4 μC/cm2 and 376.1 kV/cm, respectively at applied electric field 500 kV/cm. The dielectric constant and dielectric loss are about 310 and 0.015 at a frequency of 1 MHz, respectively. The Pr value decreased to 93% of its pre-fatigue values after 4.46×109 switching cycles at 1 MHz frenquency, and the BHT film shows good in-sulating behavior according to the test of leakage current.

关键词： Bi3.4Ho0.6Ti3O12 thin film sol-gel method ferroelectric property fatigue dielectric constant

A Single-machine Scheduling Problem with Two Agents and Decreasing Linear Deteriorating Jobs

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A Single-machine Scheduling Problem with Two Agents and Decr...

Study on Hot Deformation Cracks of Steel D2 Using Processing Map

2011 Chinese Control and Decision Conference（CCDC）

作者： Peng Liu is with the school of Management,shenyang university of technology,shenyang,110870,china .Na Yi is with the school of Sciences,liaoning Shihua university,Fushun,113001,china .Xiaoye Zhou is with the school of Management,shenyang university of technology,shenyang,110870,china.

This paper deals with the two-agent scheduling problem with decreasing linear deteriorating jobs on a single machine,where the goal is to minimize the total completion time of the first agent with the restriction that the maximum cost of the second agent cannot exceed a given upper *** agents compete to perform their respective jobs on a common single machine,and each agent has his own criterion to *** introduce a decreasing linear deterioration model into the two-agent single-machine scheduling where the processing times of jobs are defined as a decreasing linear function of their starting *** propose the optimal properties and present the optimal polynomial time algorithm to solve the scheduling problem.

关键词： Scheduling Two-agent Decreasing linear deterioration Single machine

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Journal of Iron and Steel Research International 1997年第2期4卷 46-51页

作者： Gao Shan, Liu Xianghua, Wang GuodongNortheastern university, shenyang (110006), china Northeastern university

The hot deformation behaviors of steel D2 in the range of 900 ℃ to 1 160 ℃ and strain rate range of 0.01 s -1 to 10 s -1 have been studied by using Processing Map developed on the basis of dynamic materials model. The efficiency of energy dissipation η is taken as a function of temperature and strain rate to obtain a Processing Map. In the Processing Map of steel D2, there are two zones of cracking susceptivity with high dissipation efficiency η of 46 % and 63 % respectively. One zone is in the range of 900 ℃ to 980 ℃ and the strain rate range of 0.01 s -1 to 0.06 s -1 , and the other from 1 140 ℃ to 1 160 ℃ and 8 s -1 to 10 s -1 . The experiment proves that there are microstructural brittle transgranular fractures and macroscopic thermal cracks in the two zones respectively. The map also revealed that deformation in these two zones is of instable flowing , so these two zones should be avoided when choosing hot deformation conditions.

关键词： crack,hot deformation Processing Map steel D2

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Design and Application of Decoupled Controller Based on the BP Neural Network

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Design and Application of Decoupled Controller Based on the ...

Mechanical and Frost-resistance Properties of Rural Area Building Waste Hollow Bricks

2011 Chinese Control and Decision Conference（CCDC）

作者： CUI Baoxia is the school of Information Science and Engineering,shenyang university of technology,shenyang,liaoning,110870 SUN Deyuan is the school of Information Science and Engineering,shenyang university of technology,shenyang,liaoning,110870

Composed by the neural network and traditional PID controller,a new BP neural network PID parameter self-adjustment decoupled controller is designed to realize the control of multi-input and multi-output systems in this paper,as well as to solve the problem such that the traditional PID controller can not achieve satisfied control effectiveness in multi-input and multi-output strong coupled control *** BP neural network PID controller is not only owning non-linear mapping capability,but also owning the PID capability of dealing with dynamical *** of the simple structure and algorithm,the BP neural network PID control method is more suitable for industry application.

关键词： PID Control BP Neural Network Decouple Control MIMO System

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Journal of Wuhan university of technology(materials Science) 2010年第6期25卷 1017-1021页

作者：刘军 school of Material Science and Engineering Shenyang Jianzhu University

Serving as recycled coarse aggregate,the pretreated rural building waste was added into the concrete hollow bricks in the varying replacement of 0,20%,40%,60%,80% and 100%.By testing its compressive strength,flexural strength,mass and strength loss after freeze-thaw cycles,the impact of the different replacement on mechanical and frost-resistance properties of concrete hollow bricks was presented through SEM *** experimental results show that,with the increase in recycled coarse aggregate replacement rate,the mechanical and frost-resistance properties show a downward trend;when the replacement rate is 40%,28 d compressive strength and flexural strength of concrete hollow brick demonstrate the good peak value which meet the requirement of the national standard for ordinary small concrete hollow bricks;the interfacial structures of the pretreated recycled concrete is more complicated than those of concrete made of natural aggregate,but the former enjoys better interface bonding and tight structure.

关键词： replacement rate waste clay brick mechanical properties frost-resistance properties microstructure