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Journal of Wuhan university of technology(materials science) 2011年第3期26卷 519-522页

作者：江金国崔崇 Department of materials science and engineering Nanjing University of Science & Technology

Xonotlite-type insulation material was prepared by hydrothermal synthesis technology using industrial zirconium waste residue in this paper,and the phase analysis together with the observation of micro–morphology were also carried out by XRD,SEM and *** density and thermal conductivity were measured *** results indicate,chlorine ion impurity contained in zirconium waste residue can be removed effectively via water washed process,and the reactive activity of silicon dioxide is almost not affected,which make it be a good substitution of silicon material for the preparation of calcium silicate insulation material by hydrothermal synthesis *** density and thermal conductivity of xonotlite-type calcium silicate insulation material obtained by hydrothermal synthesis technique can reach 159 kg/m3,0.049 W/（m·° C）,respectively,meeting with National Standard well,when synthesis conditions are selected as follows：Ca/Si molar ratio equal to 1,synthesis temperature at 210°C and kept for 8 *** provides a new approach to realize lightweight and low thermal conductivity of calcium silicate insulation material.

关键词： zirconium waste residue calcium silicate xonotlite hydrothermal synthesis

Research on stability of the accumulated rock-soil body of reservoir bank under rainfall condition

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science china(Technological sciences) 2009年第9期52卷 2528-2535页

作者： GU ChongShi1,2,WU HaiZhen1,2 & SU HuaiZhi1,2 1 college of Water Resources and Hydropower engineering,Hohai university,nanjing 210098,china 2 National engineering Research Center of Water Resources Efficient Utilization and engineering Safety,Hohai university,nanjing 210098,china 3 Jiangxi Water Conservancy Research Institute,Nanchang 330029,china 1. college of Water Resources and Hydropower engineering Hohai University Nanjing 210098 China 2. National engineering Research Center of Water Resources Efficient Utilization and engineering Safety Hohai University Nanjing 210098 China 3. Jiangxi Water Conservancy Research Institute Nanchang 330029 China

The shear strength parameters property of rock-soil aggregates in embankment slope of reservoir,that is,the relationship between cohesion and gravel content,between friction angle and gravel content,and the relationship between cohesion and water content,between friction angle and water content,is studied based on the direct shear test results,the shear strength change law of the rock-soil aggregates is given,and the unsaturated shear strength formulation of rock-soil aggregates that could consider suction and saturation degree influence is put forward in this paper,through which the sliding or failure physical mechanism of this type of slope under the condition of rainfall infiltration is studied. Also the 3D unsteady saturated-unsaturated seepage field and its FEM resolving mode are established based on the analysis of the slope rainfall infiltration process. Case study with this method indicates that the minimum safety factor of the accumulated rock-soil aggregates dose not arrive at the moment of rainfall cessation,but appears several hours after the rainfall cessation,this phenomenon is in accordance with the practical slope engineering's failure process and could explain appropriately the slope failure caused by rainfall infiltration. Research results in this paper have an important reference value for the research on stability of the accumulated rock-soil aggregates in embankment slope of reservoir,and can enrich the stability analysis method and relevant theory of reservoir embankment slope.

关键词： reservoir bank slope rock-soil aggregates rainfall infiltration saturated/unsaturated seepage

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 university, Changsha 410082, china 2 college of Mechanical engineering, South china university of technology, Guangzhou 510641, china 1. Center for High Resolution Electron Microscopy College of Materials Science and Engineering Hunan University Changsha 410082 China 2. college of Mechanical engineering South China University of Technology Guangzhou 510641 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 20, nitriding, composite chromizing

3D mathematical model for suspended load transport by turbulent flows and its applications

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science china(Technological sciences) 2004年第2期47卷 237-256页

作者： LU Yongjun1,DOU Guoren1,HAN Longxi2,SHAO Xuejun3 & YANG Xianghua1,3 1.nanjing Hydraulic Research Institute,nanjing 210029,china 2.college of Environmental engineering of Hohai university,nanjing 210098,china 3.Department of Hydraulic engineering,Tsinghua university,Beijing 100084,china 1. nanjing Hydraulic Research Institute 210029 Nanjing China 2. college of Environmental engineering of Hohai university 210098 Nanjing China 3. Department of Hydraulic engineering Tsinghua University 100084 Beijing China

This paper presents a 3D mathematical model for suspended load transport in turbulent flows. Based on Dous stochastic theory of turbulent flow, numerical schemes of Reynolds stresses for anisotropic turbulent flows were obtained. A refined wall function was employed to treat solid wall boundaries. The equations for 2D suspended load motion and sorting of bed material have been expanded into 3D cases. Numerical results are validated by the measured data of the Gezhouba Project, and proved to be in good agreement with the experimental. The present method has been employed to simulate sediment erosion and deposition in the dam area of Three Gorges Project, and for the operation of the project, siltation process and deposition pattern in the near-dam area of the reservoir, size distribution of the deposits and bed material, and flow fields and sediment concentration fields at different time and elevations are predicted. The predicted results are close to the experimental observations in physical model studies. Thus, a new method is established for 3D simulation of sediment motion in dam areas of multi-purpose water projects.

关键词： turbulent flows, Dou's stochastic theory, nonuniform suspended load, riverbed erosion and deposition, 3D mathematical model, Three Gorges Project.

咪唑(啉)-2-羧酸盐作为潜在的/可热活化的有机小分子催化剂催化转酯反应(英文)

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催化学报 2012年第3期33卷 502-507页

作者：王燕芹李振江南京工业大学生物与制药工程学院材料化学工程国家重点实验室江苏南京210009 南京林业大学理学院江苏南京210037

采用咪唑(啉)-2-羧酸盐(ImCO2)作为催化剂前驱体,通过温度控制脱除ImCO2的2-位羧酸根,再原位释放出高活性的N-杂环卡宾(NHCs),进而催化转酯反应.研究了NHCs在苯甲酸乙酯与一元醇、二元醇及氨基醇反应体系中的催化活性.结果表明,在该体... 详细信息

采用咪唑(啉)-2-羧酸盐(ImCO2)作为催化剂前驱体,通过温度控制脱除ImCO2的2-位羧酸根,再原位释放出高活性的N-杂环卡宾(NHCs),进而催化转酯反应.研究了NHCs在苯甲酸乙酯与一元醇、二元醇及氨基醇反应体系中的催化活性.结果表明,在该体系中不需要选用活化酯为原料,无需加入分子筛或加大醇酯比提高产率,仅用少量催化剂(0.5mol%),在较短时间内(3h),即可使反应转化率达到95%.

关键词： N-杂环卡宾有机小分子催化剂咪唑(啉)-2-羧酸盐转酯反应非活性酯

Research on semi-solid slurry of a hypoeutectic Al-Si alloy prepared by low superheat pouring and weak electromagnetic stirring

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Rare Metals 2006年第2期25卷 177-183页

作者： LIU Zheng MAO Weiming ZHAO Zhengduo material of science and engineering School University of Science and Technology Beijing Beijing 100083 China Faculty of material and Chemical engineering Jiangxi University of Science and Technology Ganzhou 341000 China

The semi-solid slurry of a hypoeutectic Al-Si alloy was manufactured by low superheat pouring and weak electromagnetic stirring. The effects of pouting temperature and stirring power on the semi-solid slurry were investigated. The results indicated that the semi-solid slurry to satisfy rheocasting can be manufactured by low superheat pouring and weak electromagnetic stirring. The pouring temperature （or superheat） and the stirring power remarkably affected the morphology of primary α-Al and the size of primary α-Al, and there is no obvious effect of stirring time on primary α-Al. Compared with the samples made by low superheat pouring with no stirring, the nucleation rate, particle morphology and grain size of primary α-Al in A356 were markedly improved by low superheat pouring and weak electromagnetic stirring. On the condition of weak electromagnetic stirring, the pouring temperature with low superheat can be suitably raised to reach the effectiveness obtained from the lower pouring temperature without stirring.

关键词： semi-solid low superheat pouring weak electromagnetic stirring hypoeutectic Al-Si alloy A356 Al alloy

Synthesis of a novel centipede-like copolymer of styrene and methyl methacrylate

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science china Chemistry 2007年第2期50卷 253-257页

作者： LI AiXiang1 & LU ZaiJun2 1 School of material science and engineering,Shandong university of technology,Zibo 255049,china 2 School of Chemistry and Chemical engineering,Shandong university,Jinan 250100,china 1. School of material science and engineering Shandong University of Technology Zibo 255049 China 2. School of Chemistry and Chemical engineering Shandong University Jinan 250100 China

A well-defined,A2B-type,centipede-like copolymer of styrene and methyl methacrylate(PS-PS-PMMA) was synthesized by the combination of living anionic polymerization and atom transfer radical polym-erization(ATRP) . The synthetic approach involves the coupling reaction of polystyrene(PS) backbone bearing 1,1-diphenylethene(DPE) pendant groups,produced by ATRP and Wittig reaction,with living polystyryllithium(PSLi) ,and subsequent polymerization of the resulting 1,1-diphenylmethyl anions with methy methacrylate. The centipede-like copolymer was characterized by 1H NMR,IR,SEC,SLS,and DSC measurements.

关键词： architecture atom transfer radical polymerization centipede-like copolymer coupling reaction living anionic polymerization

Coupling analysis of unsteady seepage and stress fields in discrete fractures network of rock mass in dam foundation

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science china(Technological sciences) 2011年第S1期54卷 133-139页

作者： CHAI JunRui 1,2 & XU WeiSheng 2 1 college of Hydraulic and Environmental engineering,china Three Gorges university,Yichang 443002,china 2 college of Hydropower engineering,Xi’an university of technology,Xi’an 710048,china 1. college of Hydraulic and Environmental engineering China Three Gorges University Yichang 443002 China2. College of Hydropower Engineering Xi’an University of Technology Xi’an 710048 China

The drag force of water flow through single fracture and the coupling characteristics of seepage and stress in single fracture surface are analyzed,and a three dimensional model of coupled unsteady seepage and stress fields is *** model is used to the analysis of foundation rock mass of a high *** the coupling effects are considered,the changes of boundary heads have less influence on the inner head of rock mass,and the strong permeability of main fractures *** the coupling effects are not considered,the fractures distribution affects the inner head more *** the upstream water head declines,the inner head of dam foundation slightly declines and the hydraulic gradient distribution becomes smoother.A bigger upstream water level declining velocity has a stronger lag effect,meanwhile the values of stress components change more *** the upstream water level declining velocity directly affects the stability of rock mass in dam foundation and we should take into account the above factors to make sure the safety of the dam during reservoir level fluctuation period.

关键词： hydraulic engineering unsteady seepage stress coupling fractures network rock mass

Hybrid method of limit equilibrium and finite element internal force for analysis of arch dam stability against sliding

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science china(Technological sciences) 2011年第4期54卷 793-798页

作者： BAO TengFei1,2,3,XU BaoSong1,2,3 & ZHENG XueQing1,2,3 1State Key Laboratory of Hydrology-Water Resources and Hydraulic engineering,Hohai university,nanjing 210098,china 2National engineering Research Center of Water Resources Efficient Utilization and engineering Safety,nanjing 210098,china 3college of Water Conservancy and Hydropower engineering,Hohai university,nanjing 210098,china 1. State Key Laboratory of Hydrology-Water Resources and Hydraulic engineering Hohai University Nanjing 210098 China2. National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Nanjing 210098 China3. College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

A hybrid method of limit equilibrium and finite element internal force for analysis of arch dam stability against sliding is *** finite element internal force method(FEIFM) is used to provide more accurate thrust forces acting on the faces of a slip body,and the limit equilibrium method(LEM) is employed to evaluate the factor of safety of the slip *** method presented can deal with a slip body with large amount of geometrically complex slip *** addition,compared with the traditional LEM,it can meet the balance condition of the forces in the slip *** example shows that the factor of safety obtained by the method presented agrees well with the theoretical solution.A practical example is also presented to demonstrate the application of the method in the stability analysis of an arch dam *** results from the examples show that the method is promising in analysis of arch dam stability against sliding.

关键词： arch dam stability against sliding limit equilibrium method finite element internal force method

Special Orientation Relationships Observed at the Early Stages of Recrystallization in Pure AlMn Alloy

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International Journal of Minerals,Metallurgy and materials 1998年第3期12卷 140-146页

作者： Ping Yang(material science and engineering School, university of science and technology Beijing, Beijing 100083, china)(Institute for Metal science and Metal Physics, Aachen university of technology, D-52056, Aachen, Germany) material science and engineering School University of Science and Technology Beijing Beijing 100083 China Institute for Metal science and Metal Physics Aachen University of Technology D-52056 Aachen Germany

Electron Back Scattering Diffraction (EBSD) technique in a SEM was used to obtain local orientationalinformation on new grains and their surrounding deformed matrices at the early stages of recrystallization in pureA1-1 .3%Mn alloy. Results show that special orientation relationships including twin-relationship often exist betweennew grains, between new grains and deformed grains or between deformed grains. The occurrence of such specialorientation relationships is attributed to the special deformation behavior in the samples with large initial grain *** formation of recrystallization twins is discussed in a different way to those of traditional ones.

关键词： Orientation relationship recrystallization AlMn, EBSD