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

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 State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special vehicle Parts Beijing 100072 China institute of technology Beijing North Vehicle Group Corporation Beijing 100072 China 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

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Solving the input data in error correc-tion of optical fabrication by finite Fourier coefficient algorithm

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Science china(Technological Sciences) 2006年第1期49卷 50-60页

作者： CHENG Haobo1,2, SUN Guozheng3 & FENG Zhijing2 1. Department of Optical Engineering, beijing institute of technology, beijing 100081, china 2. Department of Precision Instruments and Mechanology, Tsinghua University, beijing 100084, china 3. china north Industries group corporation, beijing 100089, china Department of Optical Engineering Beijing Institute of Technology Department of Precision Instruments and Mechanology Tsinghua University china north Industries group corporation

A free-form lens (FFL) is a special surface that is difficult to be fabricated. FFL are usually fabricated by computer-controlled optical surfacing (CCOS) technique. During CCOS, the material removal amount is determined by the unit removal function (URF) convoluting with the input data――the dwell time. When the removal amount and the URF are known, how to solve the input data involves the special algorithm――deconvolution. Usually, the input data are solved by virtue of low pass filter or iterative methods. However, an approximation solution would destroy the machining stability nec-essary to perform precisely CCOS. In this paper, to solve the input data, a new method that is based on the finite Fourier coefficient is put forward. It can give a continuous and accurate solution for fabricating choice. Several parameters are simulated, which influ-ence the process of CCOS, and evaluating on the effect of the method is also carried out. Experimental results verify that this method is suitable for guiding the manufacturing of high precision FFL.

关键词： optical fabrication, computer controlled optical surfacing, free-form lens, finite Fourier coefficient, error correction.

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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 (group) corporation, beijing 100041, china 3 Metallurgical Engineering Research institute, University of Science and technology beijing, beijing 100083, china School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing China Shougang technology Research institute Shougang (Group) Corporation Beijing China Metallurgical Engineering Research institute University of Science and Technology Beijing Beijing 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

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Corrosion behavior of Mg-Y alloy in NaCl aqueous solution

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Progress in Natural Science:Materials International 2012年第2期22卷 169-174页

作者： Xin Zhang a,b,c,Kui Zhang a,Xia Deng a,Hongwei Li b,c,Yongjun Li a,Minglong Ma a,Ning Li b,c,Yanlong Wang b,c 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 Center of technology,beijing north vehicle group corporation,beijing 100072,china State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special vehicle Parts Beijing 100072 China Center of technology Beijing North Vehicle Group Corporation Beijing 100072 China

The corrosion behavior of Mg-(0.25,2.5,5,8 and 15)Y alloys in 3.5wt.%NaCl aqueous solution was *** was found that the degree of corrosion deterioration increased with increasing immersion time up to 2 *** modes for the alloys with low and high content of Y element were general corrosion and pitting corrosion,respectively,and the threshold content for the corrosion mode change was 2.5%for the tested *** experimental results showed that the addition of Y refined the grain of the alloy,and the distribution,i.e.,continuous or not,of the Mg24Y5 phases had great effect on the corrosion rate and corrosion mode.

关键词： Mg-Y Corrosion Microstructure

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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 china north Industries group corporation,beijing 100081,china Department of Electronic Engineering Beijing Institute of Technology Science Research institute of china north Industries group corporation

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

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Synthesis of α-Bromine-Terminated Polystyrene Macroinitiator and Its Initiation of MMA Polymerization by ATRP

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Chemical Research in Chinese Universities 2000年第1期16卷 72-77页

作者： LIU Feng LIU Bing LUO Ning and YING Shengkang (The Laboratoric of Living Polymerization, East china University of Science and technology, Shanghai 200237, P. R. china) LIU Qing (Research institute of beijing Yanshan Petrochemical corporation, beijing 1 华东理工大学上海 200237 燕山石油化工公司研究院北京 102550

In the present paper the synthesis of block copolymers via the transformation from living anionic polymerization (LAP) to atom transfer radical polymerization (ATRP) was described. α-Bromine-terminated polystyrenes(PStBr) in the LAP step was prepared by using n-BuLi as initiator, tetrahydrofuran (THF) as the activator, α-methylstyrene (α-MeSt) as the capping group and liquid bromine (Br_2) as the bromating agent. The effects of reaction conditions such as the amounts of α-MeSt, THF, and Br_2 as well as molecular weight of polystyrene on the bromating efficiency (BE) and coupling extent (CE) were examined. The present results show that the yield of PStBr obtained was more than 93. 8% and the coupling reaction was substantially absent. PStBr was further used as the macroinitiator in the polymerization of methyl-methacrylate (MMA) in the presence of copper (I ) halogen and 2, 2' -bipyridine (bpy) complexes. It was found that the molecular weight of the resulted PSt-b-PMMA increased linearly with the increase of the conversion of MMA and the polydispersity was 1. 2-1.6. The structures of PStBr and P(St-b-MMA) were characterized by ~1H NMR spectra.

关键词： Atom transfer radical polymerization, Living anionic polymerization, Block copolymer, Macroinitiator, Bromation, α-Methylstyrene Capping reaction

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基于闭环形式的车辆减振器热学特性研究

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中国公路学报 2012年第4期25卷 153-158页

作者：么鸣涛龙凯贺李平中国航天科工集团公司第四研究院北京100854 北京理工大学机械与车辆学院北京100081 华北电力大学新能源电力系统国家重点实验室北京102206 中国航天科工集团公司北京无线电测量研究所北京100854

为了解决某车辆被动悬架系统中减振器由于温升过高而漏油失效的问题,提出了车辆悬架系统机械特性与其热学特性相互耦合的模型。采用MATLAB/Simulink建立闭环正反馈系统的热-机耦合模型,并通过仿真计算得到某车辆在多种工况以及不同悬架... 详细信息

为了解决某车辆被动悬架系统中减振器由于温升过高而漏油失效的问题,提出了车辆悬架系统机械特性与其热学特性相互耦合的模型。采用MATLAB/Simulink建立闭环正反馈系统的热-机耦合模型,并通过仿真计算得到某车辆在多种工况以及不同悬架参数条件下减振器的温升特性曲线。研究结果表明:随着路面等级的下降、车速的提高、簧上质量的增大以及悬架刚度的减小,减振器的温度升高;车轮刚度对减振器温升特性影响较小;簧下质量对减振器温升特性无影响。

关键词：汽车工程减振器仿真闭环温升

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Research on Alloying Design and Process Control for X100 Hot-Rolled Strips

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Journal of Iron and Steel Research International 2011年第S1期18卷 675-680页

作者： JIA Shu-jun 1,LIU Qing-you 1,PENG Ling-li 1,QU Peng 2 (1.china Iron and Steel Research institute group,beijing 100081,china 2.Benxi Steel group corporation,Benxi 100083,Liaoning,china) china Iron & Steel Res Inst Grp Beijing 100081 Peoples R China Benxi Steel Grp Corp Benxi 100083 Liaoning Peoples R China

The influence of alloying design,controlled rolling technology and cooling system of X100 hot-rolled strips on microstructure and micro-hardness has been discussed in detail in this *** results show that optimal chemical composition range of X100 hot-rolled strips is obtained on the basis of X80 by increasing contents of C,Mn,Ni and Mo of *** granular bainite microstructure could be refined and the volume fraction and size of M-A islands could be controlled in a reasonable range by reasonably regulating cooling rate and coiling temperature of X100 pipeline steel,which ensure high strength and toughness of X100 pipeline steel.

关键词： alloying design deformation cooling rate final cooling temperature granular bainite

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A special intermediate-low temperature PGE-As-Co mineralization

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Chinese Science Bulletin 1999年第S2期44卷 42-44页

作者： WANG Jingbin, WANG Yuwang and WANG Lijuan beijing institute of Geology for Mineral Resources, china National Nonferrous Metal Industry corporation, beijing 100012 china Research Center of Mineral Resources Exploration, Chinese Academy of Sciences, beijing 100101, china

THIS paper introduces a new type of platinum-group elements (PGE) mineralization formed under a special condition of intermediate to low temperature, i. e. Huanggang PGE-As-Co deposit related to cryptoex-plosive hornblendite, Inner Mongolia, of which the proven reserves of arsenic reached small size. 1 Geology of mineral district Huanggang PGE-As-Co deposit, located at the margin of Huanggang Mesozoic volcanic basin in thesouthern part of Da Hinggan Range, was controlled by both Huanggang-Ganzhuermiao deep fracture andvolcanic apparatus. The volcanic apparatus in a protruding cupola land-form is about 0.25 km^2. It wasfilled with rhyolitic volcanic breccia, brecciated tuff, subvolcanic dacite porphyry and brecciated lava ofvolcanic neck facies. The host hornblendite, of which Rb-Sr isochron age (bulk rock) is (90.66 ±14.44) Ma, intruded into the apparatus in the form of irregular dike (figure 1).

关键词： intermediate-low temperature PGE-As-Co mineralization Inner Mongolia.

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Application of C5-C13 light hydrocarbons in depositional environment diagnosis

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Progress in Natural Science:Materials International 2008年第9期18卷 1129-1137页

作者： Peirong Wanga,b,, Guanjun Xu a,c, Tingrong Xiaoc, Dajiang Zhanga,c, Bin Zhanga,c a Key Laboratory of Petroleum Geochemistry, china National Petroleum corporation, beijing 100083, china b Department of Organic Geochemistry, Yangtze University, Jingzhou 434023, china c Central Laboratory of Petroleum Geology, Research institute of Petroleum Exploration and Development, Petrochina, beijing 100083, china Key Laboratory of Petroleum Geochemistry China National Petroleum Corporation Beijing 100083 China Department of Organic Geochemistry Yangtze University Jingzhou 434023 China Central Laboratory of Petroleum Geology Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

Based on the geological background and Gammacerane/C31H(S + R) ratios, source rock depositional environments of the studied oil samples (194) from 13 oilfields were classified into three groups according to salinity:saline-lacustrine facies, fresh to brackish lacustrine facies (including limnetic facies), and semi-saline to saline facies (including marine facies of the Tarim Basin).C5-C13 compound groups in the crude oils were separated by GC, and about 286 compounds were qualitatively *** geochemical application of the C6-C13 compound groups and their ratios between each group with individual carbon number was *** studies show that (1) C6-C13 compound groups and their ratios in the crude oils could serve as new reliable parameters for oil-oil correlation because the C6-C13 light fractions are the major oil component, especially in light oil or condensate, in which they account for almost 90% of the whole oil;(2) the compound groups of C7 light hydrocarbons in oils derived from difierent depositional environments with difierent salinity have difierent characteristics;(3) C6-C13 compound groups and ratios may be afiected by other factors such as maturity, but they are mainly controlled by salinity of depositional waters.

关键词： Light hydrocarbons Crude oil Depositional environment Salinity

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