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Principle and Method of Optimization Design for Soft Soil Stabilizer

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Journal of Wuhan university of technology(Materials Science) 2009年第1期24卷 154-160页

作者：黄新李战国 Department of Civil Engineering BeiHang University

A stabilized soil structure formation model was introduced. In order to form compact stabilized soil structure, cementitious hydrates were needed to wrap and bind the soil aggregates. Meanwhile, expansible hydrates were needed to squeeze and fill the pores, especially the pores in the aggregates. The experimental results show that the influences of various chemical characteristic factors of soil on the strength of the stabilized soil are boiled down, for the influence on the concentration of Ca（OH）2 in the pore solution of the stabilized soil, and the amount of CSH generated by cement. Finally an optimization design method is proposed, with which the stabilizer can be designed according to characteristics of soil samples.

关键词： soil stabilization structure formation model filling pores cementing stabilizerdesign

Genesis of ^(230)Th excess in basalts from mid-ocean ridges and ocean islands:Constraints from the global U-series isotope database and major and rare earth element geochemistry

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Science china Earth Sciences 2010年第10期53卷 1486-1494页

作者： ZHANG GuoLiang1,2 & ZENG ZhiGang1 1 Key Laboratory of Marine Geology and Environment,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,china 2 Graduate university of Chinese Academy of Sciences,beijing 10004.,china 1. Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Based on 230Th-238U disequilibrium and major element data from mid-ocean ridge basalts(MORBs) and ocean island basalts(OIBs),this study calculates mantle melting parameters,and thereby investigates the origin of 230Th excess.(230Th/238U) in global MORBs shows a positive correlation with Fe8,Po,Na8,and Fmelt(Fe8 and Na8 are FeO and Na2O contents respectively after correction for crustal fractionation relative to MgO = 8 wt%,Po=pressure of initial melting and Fmelt=degree of melt),while 230Th excess in OIBs has no obvious correlation with either initial mantle melting depth or the average degree of mantle ***,compared with the MORBs,higher(230Th/238U) in OIBs actually corresponds to a lower melting *** suggests that the 230Th excess in MORBs is controlled by mantle melting conditions,while the 230Th excess in OIBs is more likely related to the deep garnet *** vast majority of calculated initial melting pressures of MORBs with excess 230Th are between 1.0 and 2.5 GPa,which is consistent with the conclusion from experiments in recent years that DU>DTh for Al-clinopyroxene at pressures of >1.0 *** initial melting pressure of OIBs is 2.2-3.5 GPa(around the spinel-garnet transition zone),with their low excess 226Ra compared to MORBs also suggesting a deeper mantle ***,excess 230Th in MORBs and OIBs may be formed respectively in the spinel and garnet stability *** addition,there is no obvious correlation of K2O/TiO2 with(230Th/238U) and initial melting pressure(Po) of MORBs,so it is proposed that the melting depth producing excess 230Th does not tap the spinel-garnet transition *** and MORBs in both(230Th/238U) vs.K2O/TiO2 and(230Th/238U) *** plots fall in two distinct areas,indicating that the mineral phases which dominate their excess 230Th are ***/Yb-Ce curves of fast and slow ridge MORBs are similar,while,in comparison,the Ce/Yb-Ce curve for OIBs shows more influence from *** mechanism

关键词： excess 230Th clinopyroxene garnet spinel-lherzolite mid-ocean ridge ocean island

Separation of Proteins by Electrophoretic Affinity Chromatography

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Chinese Journal of Chemical Engineering 1999年第4期7卷 315-320页

作者：酆韶骅刘铮丁富新袁乃驹 Tsing Hua Univ Dept Chem Engn Beijing 100084 Peoples R China

A new kind of electrophoretic affinity chromatography (EAC) for bioseparation was proposed. Separation by EAC was conducted in a multicompartment electrolyzer in which the affinity gel media were packed in one of the central compartments. The presence of an electric field accelerated the migration of proteins inside the gel matrix during adsorption and desorption processes. This led to the increase of the overall speed of separation. The present study was focused on the effect of the strength of the electric field on adsorption and desorption processes.

关键词： affinity chromatography electrophoresis electrophoretic affinity chromatography human serum albumin Cibacron Blue F3G-A

Sequence Stratigraphy of Upper Proterozoic Glacigenous Rocks in Southeastern Margin of Yangtze Platform

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Journal of Earth Science 1996年第1期15卷 38-45页

作者： Jiang Ganqing Wang Ziqiang Zhang Linghua (Department of Geology and Mineral Resources, china university of Geosciences, beijing 100083)

The Upper Proterozoic glacigenous rocks in the southeastern margin of the Yangtze platform were accumulated in a glacially influenced marine environment with extension set- ting. Two type I depositional sequences have been identified in the glacioclastic sediments the their boundaries enhanced by both tectonism and the incision of glaciation. The lower sequence (SQ1), comprising Changan and Fulu formations (Guangxi Province), Jiangkou and Xiangmen formations(Hunan Province) and their equivalents, is bounded by erosional unconformities both at the base and on the top. The upper sequence (SQ2), composed mainly of Nantuo Formation and its equivalents, is confined by an erosional unconformity at the base and covered by an exposure surface of karstification on the top. The depositional systems tracts are difficult to be distinguished directly and mainly characterized by the variation in glacioclastic supplies. Two types of episodic parasequeuces can be identified in the glacigenous rocks and are related to the evolution of depositional systems tracts. Both the sequences and parasequences are caused by autocyclic mechanism. The present research shows that the Upper Proterozoic glacigenous deposits are of significance for the analysis of the tectonic evolution of the Late Precambrian basin in South china.

关键词： glacigenous rock sequence stratigraphy Upper Proterozoic Yangtze platform.

Pyridine-H_5PMo_(10)V_2O_(4.) hybrid catalysts for liquid-phase hydroxylation of benzene to phenol with molecular oxygen

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Science china Chemistry 2009年第8期52卷 1264-1269页

作者： GE HanQing1,LENG Yan1,ZHANG FuMin1,PIAO JiaRui2,ZHOU ChangJiang1 & WANG Jun1 1 State Key Laboratory of Materials-Oriented Chemical Engineering,College of Chemistry and Chemical Engineering,Nanjing university of technology,Nanjing 210009,china 2 Petrochemical Research Institute,Petrochina Company Ltd.,{4. 100083,china 1. State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009 China 2. Petrochemical Research Institute PetroChina Company Ltd. Beijing 100083 China

Pyridine(Py)-modified Keggin-type vanadium-substituted heteropoly acids(PynPMo10V2O4.,n=1 to 5) were prepared by a precipitation method as organic/inorganic hybrid catalysts for direct hydroxylation of benzene to phenol in a pressured batch reactor and their structures were detected by *** various catalysts,Py3PMo10V2O4. exhibits the highest catalytic activity(yield of phenol,11.5%),without observing the formation of catechol,hydroquinone and benzoquinone in the reaction with 80 vol% aqueous acetic acid,molecular oxygen and ascorbic acid used as the solvent,oxidant and reducing reagent,*** of reaction temperature,reaction time,oxygen pressure,amount of ascorbic acid and catalyst on yield of phenol were investigated to obtain the optimal reaction conditions for phenol *** can greatly promote the catalytic activity of the Py-free catalyst(H5PMo10V2O4.),mostly because the organic π electrons in the hybrid catalyst may extend their conjugation to the inorganic framework of heteropoly acid and dramatically modify the redox properties,at the same time,pyridine adsorbed on heteropoly acids can promote the effect of "pseudo-liquid phase",thus accounting for the enhancement of phenol yield.

关键词： hydroxylation benzene organic/inorganic hybrid catalyst phenol heteropoly acid pyridine

Developmetn stage threshold of watershed Landforms in Loess Plateau and separation of erosion mechanism

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Journal of Geographical Sciences 2002年第1期12卷 81-90页

作者： LU Zhong-chen1, CHEN Shao-feng2,YUAN Bao-yin3,CHEN Hao4.(1.Eco-Environment Research Center,CAS,beijing 100085,china 2.Institute of Policy andManagement Science,CAS,beijing 100080,china 3.Institute of Geology,CAS,beijing1000029,china 4.Institute of Geograp

Threshold is a limit and marginal point when a qualitative change takes place. Since threshold principle was firstly used in landform research by *** in the 1970s, the quantitative research on watershed landform development stage has come true. Davis proposed a three-stage model on landform evolution: young, mature and old stages. Thereafter Strahler quantified this model by hypsometric analysis method. The authors thought that the material movement stage cannot be expressed by hypsometric method in watershed landform at development stage, because of the uncertainty on stage delimitation. To meet this shortcoming, this paper presents an integral erosion value method. A clear delimitation on landform development stage in the Loess Plateau region has been tested by this method. The result shows that gullied loessial hilly area is at the mature stage, and gullied loessial tableland area is at the young stage. It is estimated that from the point of erosion related sediment yield, natural erosion accounts for 70% of the total erosion amount, and artificial accelerating erosion is 30%. Therefore soil and water conservation is very crucial for the Loess Plateau.

关键词： landform development stage hypsometric analysis method integral erosion value natural erosion artificial accelerating erosion

Efficiency of sediment transport by flood and its control in the Lower Yellow River

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Science china(Technological Sciences) 2004年第z1期47卷 173-185页

作者： NI Jinren1, LIU Xiaoyong2, LI Tianhong1, ZHAO Ye’an3 & JIN Ling1 1. Department of Environmental Engineering, Peking university The Key Laboratory of Water and Sedi- ment Sciences, Ministry of Education, beijing 100871, china 2. General Institute of Water Resources and Hydropower Planning and Design, Ministry of Water Re- sources, beijing 100011, china 3. The Yellow River Conservancy Commission, Zhengzhou 4.0003, china 1. Department of Environmental Engineering Peking University 100871 Beijing China 2. The Key Laboratory of Water and Sediment Sciences Ministry of Education 100871 Beijing China 3. General Institute of Water Resources and Hydropower Planning and Design Ministry of Water Resources 100011 Beijing China 4. The Yellow River Conservancy Commission 450003 Zhengzhou China

This paper presents the characteristics of sediment transport by flood in the Lower Yellow River with the reach from Huayuankou to Gaocun, which is regarded as a typical braided pattern. The Artificial Neural Network Model on Water Use for Sediment Transport (WUST) by flood was established based on the measured data from 1980 to 1998. Consequently, simulations of controlling process of sediment transport by flood were made in terms of the control theory under different scenarios. According to the situation of sediment transport by flood in the Lower Yellow River, Open-Loop control system and feedback control system were adopted in system design. In the Open-Loop control system, numerical simulations were made to reveal the relationship between average discharge of flood and the WUST with varying sediment concentrations. The results demonstrate that sediment concentration has significant influence on the controlling process of flood flow to WUST. It is practical and efficient to control WUST if sediment concentration is less than 20 kg/m3. In the feedback control system, controlling processes of sediment concentration and flood discharge for sediment transport were simulated respectively under given conditions, and it was found that sediment transport process could be controlled completely by sediment concentration and discharge at the inlet of the reach from Huayuankou to Gaocun. Using the same method, controlling processes of sediment transport by flood in other reaches in the Lower Yellow River were also simulated. For the case of sediment concentration being 20 kg/m3, the optimized controlling discharge ranges from 2390 to 2900 m3/s in the lower reach of Huayuankou. This study is also of significance to flood control and flushing sediment in the Lower Yellow River with proper operation modes of Xiaolangdi Reservoir.

关键词： the Lower Yellow River, flood, sediment transport, efficiency, simulation, control.

A Cold Adhesion for Self-fused Alloy Coat by High Frequency Induction

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A Cold Adhesion for Self-fused Alloy Coat by High Frequency ...

Studies on the Synthesis of Sesamin-Group Lignans Ⅷ. A Simplified Sythesis of 2-Aryl-4.phenyloxazoles and 2-Alkyl-4.phenyloxazoles

14.(th) Congress of International Federation for Heat Treament and Surface Engineering

作者： ZHANG Zeng-zhi AI BoResearch Institute of Ecological and Functional Material china university of Mining and technology (beijing) beijing china

＜正＞ In this study, a method to prepare self-fused alloy coat, which started with a cold adhesion precoating and then induction fusing plus, is presented. It also intended to analyze the mechanism, microstructure and anitwear ability of the coat. The workpiece was precoated with Ni60 powder through an adhesion agent. The oven-dried precoat was then heated by a high frequency induction generated by 100kw power with a frequency of 250kHz. The technological parameters of the method were determined through analysis of the thermal magnetism, thermal resistivity and anti-induction mechanism. By comparing the microstructures and properties of the coat produced by cold adhesion, thermal spraying and laser refusing, it is concluded that: （1） One side of the workpiece should be preheated to 200℃before induction fusion, and the range of induction frequency should be 200-250kHz. （2） The microstructure of the coat by cold adhesion is superior to that by thermal spraying, but the particle size range should be 0.04.-0.04.mm （200-320 meshes）（3） The corrosion resistance of Ni60 coat by cold adhesion is better than that by thermal spraying, and the cold adhesion is the best method to prepare the antiwear coat.

关键词： Cold adhesion High frequency induction Ni60 coat

来源： cnki会议评论

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Chinese Chemical Letters 1997年第8期8卷 689-690页

作者： Xiao Ping NIE Zhen Qiang WANG Xiu Lin YE(Department of Chemistry,Peking university, beijing, 100871) Department of Chemistry Peking University Beijing 100871 China

The reaction of phenacyl benzoate derivatives with acetamide at about 14.°in the presence of BF3 catalyst gave 2-aryl-4.phenyloxazoles. This method can be applied to the preparation of 2-alkyl-4.phenyloxazoles as well.

关键词： Studies on the Synthesis of Sesamin-Group Lignans A Simplified Sythesis of 2-Aryl-4.phenyloxazoles and 2-Alkyl-4.phenyloxazoles