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The precipitation and effect of nano nitrides in HSLC steel

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Science china(Technological Sciences) 2008年第7期51卷 989-998页

作者： FU Jie1, LIU YangChun1,2 & WU HuaJie1,3.1 School of Metallurgical and Ecological Engineering, University of Science and Technology beijing, beijing 100083. china 2 Shougang Technology Research Institute, Shougang ({3.) corporation, beijing 100041, china 3.Metallurgical Engineering Research Institute, University of Science and Technology beijing, beijing 100083. china 1. School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China 2. Shougang Technology Research Institute Shougang (Group) Corporation Beijing 100041 China 3. Metallurgical Engineering Research Institute University of Science and Technology Beijing Beijing 100083 China

The existing forms of N and Al in HSLC (high strength low carbon) steel produced by TSCR (thin slab casting and rolling process), the precipitation thermodynamics and kinetics of AlN, and its effects on structure and mechanical property are studied. The experimental results show that only a small quantity of nitrogen is com- bined into AlN in HSLC steel produced by TSCR and most of the nitrogen in steel is still free nitrogen. Aluminum-nitride is mainly precipitated during the period of slow air cooling after coiling, but not during rolling and water cooling. The acid-soluble aluminum has no obvious effect on the grain size and mechanical property of HSLC steel produced by TSCR whose acid-soluble aluminum content is 0.005%―0.043.. The precipitation of AlN is not the main cause of grain refinement of HSLC steel produced by TSCR, nor is AlN the dominating precipitate that has precipitation strengthening effect. The nano nitrides are not pure AlN, but have complex compositions.

关键词： thin slab casting and rolling high strength low carbon steel AlN nano nitride precipitation strengthening

Application of backflush and micro-flow techniques to the analysis of C5—C13.hydrocarbons in crude oils and its geochemical significance

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Progress in Natural Science:Materials International 2007年第11期17卷 1382-1387页

作者： Wang Peirong1,2, Zhao Hong2,3. Xu Guanjun1,4, Zhu Cuishan2,3. Xiao Tingrong4, Zhang Min2,3.and Zhang Bin1,4(1. Key Laboratory of Petroleum Geochemistry, china National Petroleum corporation, beijing 100083. china 2. Geochemistry Department of Yangtze University, Jingzhou 43.023. china 3. Key Laboratory of Exploration Technologies for Oil and Gas Resources, Ministry of Education, Yangtze University, Jingzhou 43.023. china 4. Petroleum Geology Central Laboratory, Research Institute of Petroleum Exploration and Development, Petrochina, beijing 100083. china) Key Laboratory of Petroleum Geochemistry China National Petroleum Corporation Beijing 100083 China Geochemistry Department of Yangtze University Jingzhou 434023 China Key Laboratory of Exploration Technologies for Oil and Gas Resources Ministry of Education Yangtze University Jingzhou 434023 China Petroleum Geology Central Laboratory Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

An Agilent 6890N GC equipped with both FID and Agilent 5975 MSD analyzer has been employed to analyze C5—C13.hydrocarbon fractions of crude oils. A technical combination of program temperature volatilizer injection, backflush and micro-flow controller afforded a fine separation of C5—C13.compounds on a PONA column with the heavy part of crude oils being cut off before entering the analytical column. Both GC-FID chromatogram and GC-MS mass chromatograms (MID and full scan) could be obtained at the same time. The retension time differences of nC6—nC13.alkanes between GC and TIC were in the range of 0.02—0.58 minutes. Totally 286 peaks have been assigned group compositions. Results on 8 typical oil samples from CNPC Key Laboratory Crude Oil Library showed that the characteristics of C6—C13.hydrocarbon group composition could be used in oil-oil correlation studies.

关键词： GC analysis GC/MS analysis backflush micro-flow controller light fraction in crude oil

Corrosion and electrochemical behavior of as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloys in 5%NaCl aqueous solution

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Progress in Natural Science:Materials International 2011年第4期21卷 314-321页

作者： Xin ZHANG~(1,2,3.,Kui ZHANG~1,Xing-gang LI~1,Cong WANG~4,Hong-wei LI~(2,3.,Chang-shun WANG~(2,3.,Xia DENG~1 1.State Key Laboratory for Fabrication and Processing of Nonferrous Metals, beijing General Research Institute for Nonferrous Metals,beijing 100088,china 2.beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts,beijing 100072,china 3.Institute of Technology,beijing North Vehicle group corporation,beijing 100072,china 4.Fengtai Military Representative Office,beijing Military Representative Office,PLA,beijing 100072,china [a] State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China [b] beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts Beijing 100072 China [c] Institute of Technology Beijing North Vehicle Group Corporation Beijing 100072 China [d] Fengtai Military Representative Office Beijing Military Representative Office PLA Beijing 100072 China

The corrosion mechanism of the as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloy immersed in 5%NaCl aqueous solution was investigated by electrochemical test and *** electrochemical results indicate that the corrosion resistance of Mg-5Y-7Gd-1Nd-0.5Zr alloy in 5%NaCl aqueous solution gradually deteriorates with immersion time increasing from 2 h,24 h,60 h,to 108 h,which is consistent with the SEM observation of corrosion *** Cl-anion leads to the initiation and development of the corrosion pits,and Mg-5Y-7Gd-1Nd-0.5Zr alloy exhibits filiform type of attack under significant anodic control of magnesium solution *** corrosion potential becomes noble with increasing immersion time.

关键词： magnesium alloys Mg-5Y-7Gd-1Nd-0.5Zr corrosion electrochemical behavior

Modeling and characteristic analysis of underwater acoustic signal of the accelerating propeller

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Science china(Information Sciences) 2012年第2期55卷 270-280页

作者： FENG Yuan1,2,TAO Ran1 & WANG Yue11Department of Electronic Engineering,beijing Institute of Technology,beijing 100081,china 2Science Research Institute of{3. North industries group corporation,beijing 100081,china 1. Department of Electronic Engineering Beijing Institute of Technology Beijing 100081 China2. Science Research Institute of China North Industries Group Corporation Beijing 100081 China

The signal feature of propeller cavitation noise during acceleration or deceleration procedure can be used to passively detect and classify moving vessels and underwater vehicles in the port *** analyzing the chirp periodicity of the variation of propeller wake velocity under acceleration situation,this paper presents a time domain expression of the modulation envelope signal of the accelerating propeller noise,treating the signal as a Gaussian-shaped chirp periodic pulse train with increasing trend and fluctuating pulse *** paper investigates the characteristics of simplified fractional Fourier transform(SFRFT)spectrum of the chirp periodic signal,and thus obtains the relation between the chirp periodic signal and its chirp harmonics under the conditions of underwater passive ***,the experimental data of the cavitation tunnel satisfy the results obtained by simulation,which verifies the correctness of the proposed signal model.

关键词： accelerating propeller modeling of underwater acoustic signal chirp periodic signal simplified fractional Fourier transform

Spatio-temporal model for soil characteristic of reclamation land

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中国有色金属学会会刊：英文版 2005年第S1期15卷 45-48页

作者： CHEN Qiu-ji~(1, 2), HU Zhen-qi~1, FU Mei-chen~3. XIE Hong-quan~4, HAO Hai-fu~5 (1. china University of Mining and Technology(beijing Campus), beijing 100083. china 2. Henan Polytechnic University, Jiaozuo 454000, china 3. china University of Geosciences, beijing 100083. china 4. Hebei Polytechnic University, Tangshan 063.09, china 5. china Railway Shiqiju group corporation, Taiyuan 03.600, china) china Univ Min & Technol Beijing 100083 Peoples R China Henen Polytech Univ Jiaozuo 45400 Peoples R China china Univ Geosci Beijing 100083 Peoples R China Hebei Polytech Univ Tangshan 063009 Peoples R China china Railway Shiqiju Grp Corp Taiyuan 030600 Peoples R China

The development of spatio-temporal data model is introduced. According to the soil characteristic of reclamation land, we adopt the base state with amendments model of multi-layer raster to organize the spatio-temporal data, using the combined data structure on linear quadtree and linear octree to code. The advantage of this model is that it can easily obtain the information of certain layer and integratedly analyze the data with other methods. Then, the methods of obtain and analyses are introduced. The method can provide a tool for the research of the soil characteristic change and spatial distribution in reclamation land.

关键词： reclamation soil spatio-temporal data model linear quad-tree linear octree

New synthesis of amphiphilic copolymers PE-g-PEO via esterfication

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Chinese Science Bulletin 2003年第6期48卷 523-525页

作者： L?Yingying1, MA Zhi1,2, HU Youliang1, XU G. X.3.& CHUNG T. C.3.1. State Key Laboratory of Engineering Plastics, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Bei-jing beijing Lab of Catalysis, Key Lab of Catalysis of china Na-tional Petroleum corporation, beijing 100080, china 2. Graduate School of Chinese Academy of Sciences, beijing 10003., china 3. Department of Material Science and Engineering, Pennsylvania State University, University Park, PA 16802, USA State Key Laboratory of Engineering Plastics Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing Beijing Lab of Catalysis Key Lab of Catalysis of China National Petroleum Corporation Beijing China Graduate School of Chinese Academy of Sciences Beijing China Department of Material Science and Engineering Pennsylvania State University PA USA

A new series of high molecular weight amphi-philic graft copolymers PE-g-PEO has been prepared. The esterifications between PE-p-MS-g-MA and PEO with OH group at the chain end are carried out under different condi-tions. The compositions of these graft copolymers are studied by NMR and FTIR. It is found to be a convenient and effi-cient way to prepare high molecular weight PE-g-PEO graft copolymers.

关键词：聚乙烯聚(乙烯氧化物) 酯化反应合成方法亲油亲水两性片断共聚物 PE-g-PEO

Thermal Behaviors of Work Roll in Finishing Trains of Hot Rolling

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Journal of University of Science and Technology beijing 2001年第1期8卷 59-62页

作者： Anrui He, Jie Zhang, Chen Zhang, Qingdong Zhang, Gangcheng Wei, Siqing Huang Mechanical Engineering School, University of Science and Technology beijing, beijing 100083. china Wuhan Iron and Steel {3. corporation, Wuhan 43.083. china Univ Sci & Technol beijing Sch Mech Engn Beijing 100083 Peoples R China Wuhan Iron & Steel Grp Corp Wuhan 430083 Peoples R China

In order to analyze the thermal field and thermal contour of work roll in finishing trains of hot rolling in rolling process, a quasi two-dimension implicit finite difference model is developed. To improve the calculating speed and precision, some special solutions are introduced, including the development of this model, the simplification of boundary conditions and the computation of heat transfer coefficients. The results show that these solutions of thermal behaviors of work roll are very much efficient and the model can be used as an on-line profile and fatness control model of large industrial mills.

关键词： hot rolling work roll thermal behaviors finite difference method

Impact of typical environments in china’s western mountainous areas on the durability of railway concrete:a review

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Railway Sciences 2024年第5期3卷 650-669页

作者： Jiahe Wang Yanbin Tan Huajian Li Xinhua Zhong Jiaxuan Wang Yu Gao china Academy of Railway Sciences corporation Limited Railway Engineering Research InstitutionBeijingChina and State Key Laboratory of High Speed Railway Track SystemBeijingChina

Purpose–This study aims to analyze the impact mechanism of typical environments in china’s western mountainous areas on the durability of railway concrete and propose measures to improve ***/methodology/approach–With the continuous promotion of infrastructure construction,the focus of china’s railway construction has gradually shifted to the western *** four typical environments of large temperature differences,strong winds and dryness,high cold and low air pressure unique to the western mountainous areas of china have adverse effects on the durability of typical railway structure concrete(bridges,ballastless tracks and tunnels).This study identified the characteristics of four typical environments in the western mountainous areas of china through on-site *** impact mechanism of the four typical environments on the durability of concrete in different structural parts of railways has been explored through theoretical analysis and experimental research;Finally,a strategy for improving the durability of railway concrete suitable for the western mountainous areas of china was ***–The daily temperature difference in the western mountainous areas of china is more than twice that of the plain region,which will lead to significant temperature deformation and stress in the multi-layered structure of railway ballastless *** will result in *** wind speed in the western plateau region is about 2.5 to 3.times that of the plain region,and the average annual rainfall is only 1/5 of that in the plain *** drying effect on the surface of casting concrete will significantly accelerate its cracking process,leading to serious durability *** environmental temperature in the western mountainous areas of china is generally low,and there are more freeze-thaw cycles,which will increase the risk of freeze-thaw damage to railway *** environmental air pressure in the western plateau region is only 60%of that in

关键词： Western mountainous areas Concrete Durability Environment

FACTORS ANALYSIS ON IMPROVING THE PRODUCTIVITY OF THE NONFERROUS METALS INDUSTRY(2)

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中国有色金属学会会刊：英文版 1993年第2期3卷 84-87页

作者： Productivity Research group of the china National Nonferrous Metals Industry corporation,{3. 100814,china

Our research and investigation proves thatthe growth rate of the productivity of thenonferrous metals industry is much lower thanthat of investment,and that the potential for in-creasing productivity iS very grear,in spite of thecompplicated influence of multiple weak joints re-strieting the increase of the *** solvethese problems,following policies should

关键词： spite productivity creasing joints administrative hardly planned smelting accounting nonferrous