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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

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){3., 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

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

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{3. 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

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{3. 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

A new perturbation algorithm and enhancing security of SFLASH signature scheme

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Science China(Information Sciences) 2010年第4期53卷 760-768页

作者： WANG HouZhen1,2, ZHANG HuanGuo1,2*, GUAN HaiMing3.& HAN HaiQing1,2 1The Key Laboratory of Aerospace Information Security and Trusted Computing, Ministry of Education, Wuhan University, Wuhan 43.072, China 2School of Computer, Wuhan University, Wuhan 43.079, China 3.hinese Electronic Equipment System corporation, beijing 10003., China 1. The Key Laboratory of Aerospace Information Security and Trusted Computing Ministry of Education Wuhan University Wuhan 430072 China2. School of Computer Wuhan University Wuhan 430079 China3. Chinese Electronic Equipment System Corporation Beijing 100039 China

This paper introduces the concept of noise factor and noise operation, and constructs a noise group. We present a new perturbation algorithm for enhancing security of multivariate public key cryptosystems (MPKCs). European Consortium SFLASH which derives from Matsumoto-Imai scheme is a fast signature scheme intended for low cost smart cards. It was broken with the differential cryptanalysis by Dubois et al. in 2007. Taking Matsumoto-Imai system as an example, security analysis shows that the new algorithm can powerfully demolish its potential mathematical properties of the public key, and effectively avoid differential cryptanalysis without lowering the effciency of the original algorithm.

关键词： SFLASH differential cryptanalysis noise factor noise operation noise group

Effect of Welding Heat Inputs on Microstructure and Mechanical Properties of the Welding Affected Zone of 800MPa Grade Ultra Fine Microstructure Steel

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Effect of Welding Heat Inputs on Microstructure and Mechanic...

Antibiotic prescribing patterns for upper respiratory tract infections in rural Western China

第二届先进钢铁结构材料国际会议

作者： LIU Jibin~(1,2), HU Lunji~1, WANG Yutao~2, MIAO Kai~2, LIU ZhenQing~2, TIAN ZhiLing~3.(1. Huazhong University of Science and Technology, Wuhan 43.074, China 2.Technology Center of Wuhan Iron and Steel (group) corporation, Wuhan 43.080,China 3. Central Iron and Steel Research Institute, beijing 100080, China)

The microstructure and mechanical properties of the heat affected zone (HAZ) of 800MPa grade ultra fine microstructure steel was investigated by using simulated thermal cycles which represented different welding heat inputs. The analysis of HAZ microstructure found that the bainite was the main structure characteristic during different cooling time, and even in the fast cooling regime, the bainite sheaves consisted of bainite ferrite plates without carbide precipitation. The prior austenite grain of HAZ was coarsening rapidly at relatively lower cooling rate, and the bainite ferrite plates grew longer and almost developed in the same direction within a prior austenite grain. It was found that the HAZ toughness at -20℃deteriorated when the cooling time t was more than 20 seconds, and the Charpy V-notch (CVN) values was about 10J. The simulated HAZ became softer than the base metal when t was longer than 20 seconds. It was suggested that the welding heat input of this kind of 800MPa ultra fine microstructure steel should be controlled within t 15 seconds.

关键词： Ultra Fine Microstructure Steel Heat Affected Zone Heat Input Microstructure Mechanical Properties Bainite

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Journal of Pharmaceutical Analysis 2010年第4期22卷 247-251页

作者： Li-Fang Dong1,2,Hong Yan2,Jun-Hong Gao3.Duo-Lao Wang4 1.Shaanxi Center for Disease Control and Prevention,Xi’an 710054,China 2.Teaching & Research Section of Epidemiology and Health Statistics,Department of Public Health,Medical School of Xi’an Jiaotong University,Xi’an 710061,China 3.Institute of Health Research,China north industries group{3.,Xi’an 710065,China 4.Department of Epidemiology and Population Health,London School of Hygiene and Tropical Medicine,London,WC1E 7HT,UK. Shaanxi Center for Disease Control and Prevention Xi'an 710054 China Department of Public Health Medical School of Xi'An Jiaotong University Xi'an 710061 China Institute of Health Research China North Industries Group Corporation Xi'an 710065 China Department of Epidemiology and Population Health London School of Hygiene and Tropical Medicine London WC1E 7HT United Kingdom

Objective To explore the prescribing patterns of outpatients receiving antibiotics for upper respiratory tract infections(URTIs)in rural Western China and to identify the correlation in terms of doctors and patients *** Totally 7 678 prescriptions for URTIs were collected from 680 primary health village clinics of 40 counties across 10 provinces of Western *** outcome variables were used in the analysis:the occurrence of prescribing at least one antibiotic drug for an URTI and the occurrence of prescribing two or more antibiotics for an *** logistic regression models were used to examine the socioeconomic and demographic determinants of the above two outcome *** The percentage of prescribing at least one antibiotic for URTIs was 48.6% while the percentage of prescribing antibiotic combination(two or more antibiotics)was 4.6%.The two measurements of antibiotic utilization differed remarkably among the 10 *** diagnosed with tonsillitis and faucitis had higher odds(OR=8.86 for tonsillitis and OR=4.64 for faucitis)of antibiotic prescription than patients with other diagnosis of *** with tonsillitis and faucitis also had higher odds(OR=3.82 for tonsillitis and OR=2.71 for faucitis)of multiple antibiotic prescription than those with other diagnosis of *** number of drugs per prescription and injection in prescriptions were also significant predictors of antibiotic and multiple antibiotic utilization for *** It is concluded that the percentage of antibiotic prescription for URTIs is higher in rural Western China than in most of other countries with available data and that prescriptions of antibiotics for URTIs are associated with residence regions of patients,URTI diagnosis and background information on drug prescription.

关键词： antibiotics pharmacoepidemiology upper respiratory tract infection rural population