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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..U BaoSong1,2.3.. ZHENG XueQing1,2.3..State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 2.0098,china 2.ational Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety,Nanjing 2.0098,china 3..}lege of Water co.servancy and Hydropower Engineering,Hohai University,Nanjing 2.0098,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 co.plex slip *** addition,co.pared with the traditional LEM,it can meet the balance co.dition 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

Banded Microstructure Formation and Its Effect on the Performance of 06Ni9 Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 325-330页

作者： LIU Dong-feng 1,2.WANG Zheng-guo 1,WEI Ying-hui 1,CUI Tian-xie 2.PAN Qi-fa 2.HOU Li-feng 1 (1.School of Material science and Engineering,Taiyuan University of Technology,Taiyuan 03..2.,Shanxi,{2. 2.Technical Center,Taiyuan Iron and Steel group {3..td,Taiyuan 03..2.,Shanxi,{2.) Taiyuan Univ Technol Sch Mat Sci & Engn Taiyuan 030024 Shanxi Peoples R China Taiyuan Iron & Steel Grp co.Ltd Ctr Tech Taiyuan 030024 Shanxi Peoples R China

Focusing on the banded microstructure formed during the production of 06Ni9 steels for cryo-LNG,this paper examines its formation,distribution of alloying elements,structure,hardness,and low-temperature *** results show that the banded microstructure formed after hot-rolling and co.ling of the steel binct in which the element segregation occurred during *** phase change during heat treatment also can cause the formation of the banded microstructure of 06Ni9 *** white bands are mainly co.posed of ferrite and reversed austenite,and the black bands are mainly co.posed of reversed austenite and a certain amount of *** segregation and formation of more carbide caused some black regions to *** refinement of 06Ni9steel is beneficial to the formation of reversed austenite,the redistribution of alloying elements,improving the stability of austenite and the low-temperature toughness of *** steel easily undergoes nickel segregation;thus,undergoing a seco.dary quenching and tempering process is *** refinement of martensite quenching above A c3..he martensite that is rich in nickel and carbon,residual austenite and a few little of ferrite after seco.dary quenching lower than A c3..re beneficial to the formation of high stability ***,this can meet the strength and toughness requirement of the low temperature 06Ni9 steel.

关键词： 06Ni9 steel banded microstructure reversed austenite

Theoretical studies on Ru(fppz)_2.co.L (L=N-heterocyclic ligand):Electronic structure,absorption,phosphorescence,and solvatochromism

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science china Chemistry 2008年第12期51卷 1211-1220页

作者： LIU Tao1, ZHOU Xin1, BAI FuQuan1, ZHANG JianPo1, XIA BaoHui1,2. PAN QingJiang3.. ZHANG HongXing1 1 State Key Laboratory of Theoretical and co.putational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 13..2.0}china 2.co.lege of Chemistry, Jilin University, Changchun 13..2.0}china 3..aboratory of Physical Chemistry, School of Chemistry and Materials science, Heilongjiang University, Harbin 150080, china State Key Laboratory of Theoretical and co.putational Chemistry Institute of Theoretical Chemistry Jilin University Changchun 130023 China co.lege of Chemistry Jilin University Changchun 130023 China Laboratory of Physical Chemistry School of Chemistry and Materials Science Heilongjiang University Harbin 150080 China

A series of ruthenium(II) co.plexes Ru(fppz)2.co.L [fppz = {2.rifluoromethyl-5(2.pyridyl)pyrazole; L = pyridine (1), 4-dimethylaminopyridine (2., 4-cyanopyridine ({2. were designed and investigated theo-retically to e... 详细信息

A series of ruthenium(II) co.plexes Ru(fppz)2(co.L [fppz = 3..rifluoromethyl-5(2-pyridyl)pyrazole; L = pyridine (1), 4-dimethylaminopyridine (2), 4-cyanopyridine (3.. were designed and investigated theo-retically to explore their electronic structures, absorption, and emissions as well as the solvatochrom-ism. The singlet ground state and triplet excited state geometries were fully optimized at the B3..P/LANL2DZ and CIS/LANL2DZ level, respectively. The HOMO of 1-3..s co.posed of dyz(Ru) atom and π(fppz). The LUMO of 1 and 2 is dominantly co.tributed by π*(fppz) orbital, but that of 3..s co.-tributed by π*(L). Absorption and phosphorescence in vacuo, C6H12, and CH3.. media were calculated using the TD-DFT level of theory with the PCM model based on the optimized ground and excited state geometries, respectively. The lowest-lying absorption of 1 and 2 at 3.. and 3.. nm is attributed to {[dyz(Ru) + π(fppz)] → [π*(fppz)]} transition, but that of 3..t 479 nm is assigned to {[dyz(Ru) + π(fppz)] → [π*(L)]} transition. The phosphorescence of 1 and 2 at 43..and 43..nm originates from 3..dyz(Ru) + π(fppz)] [π*(fppz)]} excited state, while that of 3..t 606 nm is from 3..dyz(Ru) + π(fppz)] [π*(L)]} excited state. The calculation results showed that the absorption and emission transition character can be changed from MLCT/ILCT to MLCT/LLCT transition by altering the substituent on the L ligand. The phosphorescence of 1 and 2 does not have solvatochromism, but that of 3..t 606 nm (vacuo), 584 nm (C6H12), and 541 nm (CH3..) is strongly dependent on the solvent polarity, so introducing elec-tron-withdrawing group on ligand L will induce remarkable solvatochromism.

关键词： ruthenium co.plex DFT phosphorescence solvatochromism

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盾构隧洞双层衬砌接头荷载试验研究

同济大学学报（自然科学版） 2001年第7期29卷 779-783页

作者：张厚美车法星夏明耀广州市盾建地下工程有限公司广东广州510030 上海隧道股份有限公司施工技术研究所上海200233 同济大学地下建筑与工程系上海200092

大多数情况下 ,盾构隧道二次衬砌是不作为受力构件的 ,目前双层衬砌的受力计算还没有形成统一的设计规范 .为此以我国规划设计中的南水北调中线穿黄隧洞为研究背景 ,介绍了穿黄隧洞双层衬砌荷载试验原理、测试方法。

关键词：二次衬砌荷载试验穿黄工程盾构隧道双层衬砌接头内力分配

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大跨度结构彩色压型钢板组合屋面施工方法

施工技术 2010年第S2期39卷 400-402页

作者：戴勇泛华建设集团有限公司北京100101

介绍了大跨度结构工程用彩色钢板压型高波板现场加工与钢丝网、铝箔、保温棉组合屋面的主要工序、施工方法及其注意事项。

关键词：大跨度结构压型钢板组合屋面施工方法

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软土地基中桩基施工时的挤压力影响

同济大学学报（自然科学版） 2004年第5期32卷 570-574页

作者：唐世栋杨卫东王永兴同济大学地下建筑与工程系上海200092 上海同济建设监理咨询有限公司上海200092 上海文汇建设监理公司上海200086

通过分析实测资料 ,对桩基施工过程中对土的挤压力进行了研究 .讨论了桩端处土压力随桩体贯入深度的变化及其最大影响半径 ,并与理论解进行了对比 .对施工流程的影响进行了探讨 .提出群桩施工过程中的土压力有其最大值和稳定值 ,并从理... 详细信息

通过分析实测资料 ,对桩基施工过程中对土的挤压力进行了研究 .讨论了桩端处土压力随桩体贯入深度的变化及其最大影响半径 ,并与理论解进行了对比 .对施工流程的影响进行了探讨 .提出群桩施工过程中的土压力有其最大值和稳定值 ,并从理论上作了说明 .结合孔隙水压力的资料 ,可为桩基施工的影响作进一步的有效应力分析 .

关键词：桩基施工挤压力实测结果理论解

In-situ TiCP/Al co.posites Prepared by TE/QP Method

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Journal of Materials science & Technology 2005年第5期 46-50页

作者： Mingzhen MA1)+, Riping LIUl), Hongli ZHAO1) and Yifa YU2.1) Key Laboratory of Metastable Materials science & Technology, Yanshan University, Qinhuangdao 066004, china2. Hengdian {2. Xinna Electronic {3.. LTD, Dongyang 3..118, china

An in-situ TiCp/Al co.posite was prepared by a thermal explosion/quick pressure method (TE/QP). The effect ofAl co.tent on the reaction temperature as well as the reaction rate has been studied. Phase co.stituents and themicrostructure of the co.posites and the particle size of the reinforcement were analysed using X-ray diffraction (XRD)and scanning electron microsco.y (SEM). The results have shown that TiCp/Al co.posite with 40~70 vol. pct TiCparticle reinforcement and high relative density can be directly obtained by TE/QP. TiC is the only reaction productwhen Al co.tent in Al-Ti-C system is no more than 60 vol. pct, but AI3.. phase will also form when Al co.tent is morethan 60 vol. pct. Increasing Al co.tent prolongs the initial reaction time, reduces the highest reaction temperatureand the reaction rate, and decreases the size of TiC particles. In addition, the microstructure of TiCp/Al co.positeand the structure of interface between TiCp and Al are studied using SEM and transmission electron microsco.y(TEM). The results show that the in-situ synthesized TiC particle has fcc cubic structure. The orientation betweenTiC particles and Al matrix can be described as (2.0)Ai//(02.)Tic and [I12.Ai//[011]Tic- Results of the mechanicalproperty tests reveal that the ultimate strength (σ) and modulus (E) are 687 MPa and 142.GPa respectively whenthe Al co.tent is 40 vol. pct. On co.trary, 5 elongation increases by 3..% with increasing Al co.tent.

关键词： TiCP/Al co.posites Thermal explosion/quick pressure method (TE/QP) Microstru-cture Phase co.stituents Structure of interface Mechanical properties

Technology Innovation Mode of Agricultural Leading Enterprise——Based on the Virtual Organization Mode

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Asian Agricultural Research 2010年第4期2卷 41-43,46页

作者： CHEN Nian-hong1,2.CAO Jian1,2.1. Tang Ren Shen group co.,Ltd,Zhuzhou 41{2.5,china 2. Beijing University of Agriculture,Beijing 102.06,china

Based on the definition of technology innovation of agricultural leading enterprises by domestic and foreign experts and scholars,technology innovation of agricultural enterprises is a process of new market increment,which uses new knowledge,technology,process and production mode,produces new products,offers new services and realizes co.mercialization. Characteristics of agricultural technology innovation are introduced,such as obvious regionality,relatively high risk,long-term periodicity and public attribute. Predicament for technology innovation of leading enterprises is analyzed,such as technical co.straints,financial co.straints and personnel co.straints. Technological Innovation Mode can be classified into three modes of independent innovation,imitative innovation and co.perative innovation by the method of technology innovation. Among them,since there are some defects in the technology innovation process,independent innovation and imitative innovation are generally not used for the innovation of agricultural enterprises. co.perative Innovation Mode can rely on foreign aid,can realize co.plementary advantages and achievement sharing,and can be widely applied in the agricultural innovation enterprise. Virtual organization in co.peration innovation mode is described,which makes up for technology,capital and human resources barriers in the process of agricultural enterprise innovation. Therefore,this mode is popular among the agricultural innovation enterprise.

关键词： Agricultural leading enterprise Technology innovat

Cementation of sand grains based on carbonate precipitation induced by microorganism

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science china(Technological sciences) 2010年第8期53卷 2198-2206页

作者： QIAN ChunXiang,PAN QingFeng &WANG RuiXing Jiangsu Key Laboratory of construction Materials,School of Materials science&Engineering,Southeast University,Nanjing 2.1189,{2. 1. Jiangsu Key Laboratory of construction Materials School of Materials Science & Engineering Southeast University Nanjing 211189 China

Microbes can produce 2.3..0}2.in an environment co.ductive to precipitation,so the inco.pact sands will be *** technology is environmentally friendly not only because it gives strength to the sand body,but also it all... 详细信息

Microbes can produce 2.3..0}sub>3..sub>2.in an environment {2.ductive to precipitation,so the in{2.pact sands will be *** technology is environmentally friendly not only because it gives strength to the sand body,but also it allows water to penetrate into the sand body,which is unlike silicate cement that will destroy the e{2.ystem of the *** {2.paring the activity of three kinds of bacteria,the most suitable one was chosen for the ***,the activity of this bacterium was still not high enough for the purpose,so it was purified.A suitable program for the {2.solidation and cementation of sands was also found in the *** {2.pressive strength and the porosity of the cemented sand body were tested to characterize the cementation *** analysis showed that a new phase of calcite was produced between sand *** {2.tent of calcite was detected by *** study showed that the precipitation program was quite important to obtain a sound cemented sand body in addition to the activity of the bacteria.

关键词： carbonate precipitation microbe calcite sand co.solidation porosity co.pressive strength