检索结果-南通市图书馆

Effects of Ultrasonic Field on Microstructures and Properties of Semi-solid AZ91D Magnesium Alloy

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Wuhan university of Technology(Materials Science) 2010年第4期25卷 555-560页

作者：陈国平 mechanical engineering Institute Hunan Industry University(Zhuzhou) mechanical and Electrical engineering Institute Nanchang University

The microstructure distribution rule of semi-solid AZ91D alloy treated by ultrasonic was researched, and mechanical properies of specimens before and after ultrasonic treatment were investigated ***-solid AZ91D melt specimens were processed by ultrasonic under different powers, and its microstructures and mechanical properties at different sampling points in specimens were obtained. The experimental results show that the microstructure of AZ91D alloy at different sampling points under the same ultrasonic power is different in grain size and shape, and there is also great difference among their microstructures at the same sampling point under different ultrasonic powers. AZ91D alloy treated by ultrasonic can obtain increment in both tensile strength and plasticity. Under same ultrasonic power, mechanical properties of specimen at different sampling points have obvious difference, and regularity for change of mechanical properties everywhere is similar to regularity for change of grain size and shape everywhere.

关键词： magnesium alloy AZ91D ultrasonic treatment semi-solid structure distribution rule

Effect of static magnetic field on activity of immobilized α-amylase

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1997年第2期42卷 127-130页

作者： YAN Liushui, ZHU Yuanbao, HE-Shuang’e and CAO Zhixiang1 Department of Chemical engineering, nanchang Institute of Aeronautical Technology, nanchang 330034, china 2. Department of Chemistry and Chemical engineering, Hunan university, Changsha 410082. china Department of Chemical engineering Nanchang Institute of Aenwututical Techndogy Nanchang China Department of Chemistry and Chemical engineering Hunan University Changsha China

BIOLOGICAL effect of magnetic field is one of the three major subjects of contemporary biomagnetism, and is also the basis of applied biomagnetism. In order to explore magnetic biological effects, the influence of various sorts of magnetic field on many living systems as well as their different constructural levels has been extensively studied. However, only a few studies with in vitro enzyme have been reported, and few researches concerning the influence of magnetic field on immobilized enzyme reactions have been published. This note describes

关键词： static magnetic field immobilized α-amylase enzyme activity oscillatory behaviour.

Research on Constructing a System of Cultivating Extracurricular Scientific and Technological Innovation in university Students—Based on the practical analysis of mechanical {2.

在线全文

学校读者我要写书评

暂无评论

Research on Constructing a System of Cultivating Extracurric...

A NEW TURBULENCE MODULATION IN SECOND-ORDER MOMENT TWO-PHASE MODEL AND ITS APPLICATION TO HORIZONTAL CHANNEL

第三届教学管理与课程建设学术会议

作者： Xiaoming SHI 1 , Wei QIAN 2.1 School of mechanical engineering, USST, Shanghai,{2. 2.School of mechanical engineering, USST, Shanghai,{2.

Cultivating the sense of innovation in university students is one of the aims for institutions of higher education in china. We attempt to explore a system of cultivating extracurricular scientific and technological innovation in the university of Shanghai for Science and Technology. The exploration is made from both the macro perspective and the micro procedures, in combination with taking advantage of the considerable teaching resources if necessary. General principles, specific methods and particular activities in this system are discussed in detail. The research serves to be supplementary work concerning the cultivation of the sense of innovation among university students given the success we have achieved.

关键词： Education Model university Students Innovation Cultivating System

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2008年第3期20卷 331-338页

作者： ZENG Zhuo-xiong Aeronautic and mechanical engineering College Nanchang Hangkong University Nanchang 330063 China

A new second-order moment two- phase turbulence model accounting for particle wake effect was established and used to simulate gas-particle flow in a horizontal channel for different values of wall roughness. The results show that compared with the model without considering the particle wake effect, the present model gives simulation results agreeing much better with the experimental results for the gas turbulence modulation, but the predicted results for particle motion with the two kinds of models are quite close.

关键词： gas-particle flows turbulence modification numerical simulation

Non-isothermal Melt Crystallization Kinetics of Anhydrite-Filled Polypropylene Composites

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan university of Technology(Materials Science) 2010年第1期25卷 12-19页

作者：王少会 Department of Chemistry and Chemical engineering East China JiaoTong University

The non-isothermal crystallization kinetics of polypropylene （PP）, PP/anhydrite composites were investigated by differential scanning calorimetry （DSC） with various cooling rates. The Avrami analysis modified by Jeziorny and a method developed by Mo were employed to describe the non-isothermal crystallization process of these samples. The difference in the exponent n between PP and PP/anhydrite composites indicated that non-isothermal kinetic crystallization corresponded to tri-dimensional growth with heterogeneous nucleation. The values of half-time, Zc and F（T） showed that the crystallization rate increased with the increasing of cooling rates for PP and PP/anhydrite composites, but the crystallization rate of PP/anhydrite composites was faster than that of PP at a given cooling rate. The method developed by Ozawa did not describe the non-isothermal crystallization process of PP very well. Moreover, the method proposed by Kissinger was used to evaluate the activation energy of the mentioned samples. The result showed that the activation energy of PP/anhydrite was greatly larger than that of PP.

关键词： polypropylene anhydrite composites non-isothermal crystallization kinetics

SECOND-ORDER MOMENT TWO-PHASE TURBULENCE MODEL ACCOUNTING FOR TURBULENCE MODULATION IN SWIRLING SUDDEN-EXPANSION CHAMBER

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2008年第1期20卷 54-59页

作者： ZENG Zhuo-xiong Aeronautic and mechanical engineering College Nanchang Hangkong University Nanchang 330063 China

A semi-empirical turbulence enhancement model accounting for the particle-wake effect was incorporated into the second-order moment two-phase turbulence model and employed to simulate gas-particle flows in a swirling sudden-expansion chamber. The simulated results for two-phases mean velocities and fluctuation velocities coincide well with the experiment ones, which demonstrates that this model, in comparison with the turbulence model not accounting for the wake effect, leads to higher calculating accuracy.

关键词： gas-particle flows turbulence modulation particle wake effect

A SECOND-ORDER MOMENT TURBULENCE MODEL FOR POWER LAW FLUID WITH PARTICLES

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2007年第5期19卷 607-612页

作者： ZENG Zhuo-xiong PAN Yang ZHONG Chun QIU Guo-bin Aeronautic and mechanical engineering College Nanchang Hangkong University Nanchang 330063 China School of Civil engineering and Architecture East China Jiaotong University Nanchang 330013 China

The USM-θ model of power law fluid for dense two-phase turbulent flow was developed, which combines the unified second-order moment model for two-phase turbulence with the particle kinetic theory for the inter-particle collision. This model was used to simulate the turbulent flow of power law fluid single-phase in pipe. It is shown that the USM- θ model has better prediction result than the κf -κf - κ- εp -θ model. The USM-O model was then used to simulate the dense two-phase turbulent up flow of power law fluid with particles. With the increase of the flow exponent, the velocities of power law fluid and particles increase near the pipe centre. Comparison between the two-phase flow of power law fluid-particle and of liquid-particle indicates that the axial fluctuation velocity of fluid phase and particle phase in liquid-particle two-phase flow is smaller than that in the power law fluid two-phase flow, but the two-phase velocities of power law fluid-particle and liquid-particle are close to each other.

关键词： power law fluid two-phase flow second-ordermoment turbulence model

Analysis on the long term discharge of a catchment

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2000年第3期12卷 279-285页

作者： HONG Lin 1, TAKASE Keiji 2. SATO Koichi 2.(1. Wuhan university of Hydraulic and Electric engineering, Wuhan 430072.{2. 2. Ehime university, Japan) Wuhan university of Hydraulic and Electric engineering Wuhan 430072 China Ehime university Japan

In this study, the characteristics of the long term discharge of a Terraced Paddy Field Catchment are studied. 2.Kind of Tank Models are proposed and used to simulate the discharge of the catchment. The characteristics of the model simulations of the discharge of the catchment are analyzed and compared with those of a forest catchment.

关键词： long term discharge model simulation terraced paddy field catchment

Synthesis of vertically aligned carbon nanotube arrays on silicon substrates

在线全文

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2004年第5期47卷 616-624页

作者： ZHENG Ruiting1, CHENG Guoan1, PENG Yibin1, 2. ZHAO Yong1, 3, LIU Huaping1 & LIANG Changlin1 1. Key Laboratory of Radiation Beam Technology and Materials Modification of Ministry of Education, Department of Materials Science and engineering, Beijing Normal university, Beijing 100875,{2. 2. School of Science, Civil Aviation university of{2., Tianjin 300300,{2. 3. Department of Physics, nanchang university, nanchang 330047,{2. Correspondence should be addressed to Zheng Ruiting 1. Key Laboratory of Radiation Beam Technology and Materials Modification of Ministry of Education Department of Materials Science and Engineering Beijing Normal University 100875 Beijing China 2. School of Science Civil Aviation University of China 300300 Tianjin China 3. Department of Physics Nanchang University 330047 Nanchang China

The growth of well-aligned carbon nanotube (CNT) arrays using a heat chemical vapor deposition system on silicon substrates is reported. The growth properties of CNT arrays are studied as a function of synthesis conditions. It is found that 750°C and 10 nm Fe film are suitable conditions for the growth of well-aligned CNT arrays. CNT arrays with a uniform diameter, thick tube wall and firm cohesion to the Si substrate can be grown for C2.2.concentration of 2.%. Based on the experiment, the processes of improving the alignment of CNT arrays and cohesion between CNT arrays and Si substrates are discussed.

关键词： carbon nanotubes, vertically aligned, silicon substrate, chemical vapor deposition.