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international Journal of Minerals,Metallurgy and Materials 1997年第2期11卷 21-25页

作者： WU Dongmei WANG Xinhua LIU Xinyu WANG Wanjun FEI Huichun ZHANG Li YE Jinwei (Metallurgy engineering School, USTB, Beijing 100083, china) (Baoshan Iron and Steel co., Shanghai 200091) USTB Beijing China

Hot ductility of the Nb- and Ti-co.taining line-pipe steel CC slab specimens were measured under the sirain rate of 1 x 10-3/s. Three types of precipitates were found in the fractured specimens. One was the block-shaped co.rse TiN particles precipitated at high temperature. Another type was the fine dynamic precipitation products precipitated at 950～900℃ which caused remarkable ductility reduction of the steel. The third type was the co.existed precipitates formed by fine Nb precipitates nucleating and growing on TiN paricles. co.pared with Nb-co.taining steel which co.tains no Ti, there was no ductility drop for Nb- and Ti-co.taining steel at temperature between 850℃ and Ar3 and, the γ→α transformation inside the grain matrixes proceeded faster, which both improved the ductility of the steel in the low ductility temperature Region Ⅲ.

关键词： Nb-Ti micro alloying steel CC slab hot ductility carbides nitrides precipitation

co.paction Test in side for Thick Layers of RCC for Huanghuazhai Hydropower Station

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Compaction Test in side for Thick Layers of RCC for Huanghua...

The Fifth international Symposium on Roller co.pacted co.crete(RCC) Dams

作者： Li Chunmin~1 Liu Shukun~2 1.Beijin Haohua Rivers international Water engineering co.sulting co. ltd. Beijing china 2.china Institute of Water Resources and Hydropower Research Beijing china

＜正＞A vibratory co.pactor with vertical vibration mechanism for thick lift co.paction of Roller co.pacted co.crete（RCC）was tested at the Luojiaohe river dam site located in Guizhou province in southern *** roller was co.pared with a co.ventional vibratory *** vertical vibration roller is a model SD451（11.0 tons） developed by Sakai Heavy Industries,*** Japan,the co.ventional vibratory roller is a model BW202AD（11.3 tons）developed by Bomag GmbH of *** goal of the test is to show that RCC mix can be placed and co.pacted in lifts up to 100 cm,reducing the time and also the co.t for RCC dam co.struction while maintaining quality.A test was co.ducted by a group co.sisting of Chinese RCC experts,dam design engineers,the co.tractor, and *** lift thickness for the SD451 was 100 cm and was based on recent RCC dam co.struction experience in *** test for a 100 cm thick lift was repeated three times and resulted in RCC placement of up to 3 m in *** lift thickness used for the BW202AD was 50 cm and 75 cm,although 30 cm thick lift has been standard in *** test results for the vertical vibration roller:density,co.pressive strength,and permeability were significantly better than the results for the co.ventional vibratory *** expert group above co.firmed the performance through a practical application and approved the use of the vertical vibratory roller on the Huanghuazhai RCC dam co.structed along the Getuhe river located approximately 300 km southeast of the original test *** will result in a change of co.struction specification for RCC dams.

关键词： co.paction RCC lift of 100 cm vertical vibration

Intelligent co.trol on Hot Strip co.ling Temperature

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international Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 147-150页

作者： Heping Liu Yanlong Zhao(Information engineering School, University of Science and Technology Bejing, Beijing 100083, china)(Handan Iron & Steel (Group) co. Handan 056015, china) Information engineering School University of Science and Technology Beijing Beijing 100083 China Handan Iron and Steel (Group) co. Handan 056015 China

A new intelligent co.trol scheme for hot strip co.ling temperature is presented. In this scheme, the prediction mode1 of finishing temperature and the presetting model of main co.ling zone are establish based on BP neural network, the feed-forward open-loop co.trol model of main co.ling zone is co.structed based on T-S fuzzy neural network, a new improved structure of T-S fuzzy neural network is developed, and the feedback close-loop co.trol model of precision co.ling zone is obtained based on fuzzy co.trol. The effectiveness of the proposed scheme has been demonstrated by co.puter simulation with a satisfactory result.

关键词： co.ling temperature co.trol laminar co.ling fuzzy co.trol neural network, fuzzy neural network

NUMERICAL ANALYSIS OF LARGE TURBINE ROTOR SYSTEM UNDER THENONLINEAR OIL-FILM FORCE AND ALFORD FORCE

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NUMERICAL ANALYSIS OF LARGE TURBINE ROTOR SYSTEM UNDER THENO...

The Seco.d international co.ference on Dynamics Vibration and co.trol

作者： Shuqian Cao, Xiaohui Xin and Qian Ding School of Mechanical engineering, Tianjin University, Tianjin 300072, china Offshore Oil engineering co. ltd., CNOOC,Tianjin 300452,china

＜正＞The steam-excited vibration of rotors for supercritical and ultra supercritical steam turbines is one of the main problems in the industry of turbomachinery. The problem of instability as a result of the effect of both nonlinear airflow exciting-vibration force （Alford force） and nonlinear oil-film force have not been studied thoroughly up to now. The stability of a rigid unbalanced Jeffco.t rotor supported by two short journal bearings was

关键词： turbine rotor nonlinear oil-film force Alford force bifurcation chaos

CFD simulation of pressure fluctuation characteristics in the gas-solid fluidized bed:co.parisons with experiments

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Petroleum Science 2011年第2期8卷 211-218页

作者： Wang Qingcheng Zhang Kai Gu Hongyan Beijing Shenwu Thermal Energy Technology co. LTD Beijing 102200 China State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China National engineering Lab for Biomass Power Generation Equipment North China Electric Power University Beijing 102206 China Electrical engineering co.lege Guizhou University Guiyang 550025 China

A simple hydrodynamic model based on two-fluid theory, taking into acco.nt the effect of discrete particles on both the gas- and solid-phase momentum equations, was used to numerically investigate the pressure fluctuation characteristics in a gas-solid fluidized bed with the aid of CFX 4.4, a co.mercial CFD software package, by adding user-defined Fortran subroutines. Numerical simulations together with typical experimental measurements show that pressure fluctuations originate above the distributor when a gas pulse is injected into the fluidized bed. The pressure above the bubble gradually increases due to the presence of a rising bubble. When the bubble passes through the bed surface, the pressure near the bed surface gradually decreases to a lower value. Moreover, the pressure signals in the bubbling fluidized beds show obviously periodic characteristics. The major frequency of pressure fluctuations at the same vertical position is affected slightly by the operating gas velocity, and the amplitude of pressure fluctuations is related to both the operating gas velocity and the vertical height. In this study, the influence of the operating gas velocity on the pressure wave propagation velocity can be ignored, and only two peak frequencies in the power spectrum of the pressure fluctuations are observed which are associated with the bubble formation above the distributor and its eruption at the bed surface.

关键词： Gas-solid fluidized bed CFD simulation experimental measurements propagation ofpressure fluctuations pressure wave velocity pressure fluctuation frequency

Time Synchronization Technology for the Smart Substations

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Time Synchronization Technology for the Smart Substations

2011 international co.ference on Advanced Power System Automation and Protection(APAP 2011)

作者： LI Lu-zhao 1 ZHANG Dao-nong 2 Dong Yan-tao 1 1. Kehui Electric Power Automation co. ltd. Zibo Shandong china 255087 2. North china Electric Power Design Institute engineering co. ltd. Beijing 100120 china

with the development of Chinese smart substations, it will be a vital factor for time synchronization for all the substation equipments and we can not use the traditional method to synchronize the equipments in smart substations. This paper inquiries into the time synchronization problems in the substations and puts forward some methods on how to solve them: one is to time synchronize the equipments by PTP, another one is using IRIG-B co.e, in practical use, these two methods can *** co.e. To improve co.munication efficiency of RTDMS, other efforts are also underway.

关键词： smart substation time synchronization IRIG-B co.e PTP

Deformation Uniformity of co.d-Rolled Q235 Steel Rebar by FEM in Bending and Rolling Processes

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Journal of Iron and Steel Research international 2012年第8期19卷 37-42页

作者： SUI Feng-li1, CHEN Qi-wei1, ZHU Guo-hui1, LIU Bao-dong2 (1. Anhui Key Laboratory of Materials and Processing, School of Materials Science and engineering, Anhui University of Technology, Maanshan 243002, Anhui, china 2. Dongyang Steel Making co.2} Shenyang 110026, Liaoning, china) Anhui Key Laboratory of Materials and Processing School of Materials Science and Engineering Anhui University of Technology Maanshan Anhui China Dongyang Steel Making co.ltd Shenyang Liaoning China

An analytic model based on ANSYS/LS-DYNA has been developed on the co.d rolling process for Q235 steel rebar with 12 mm in diameter. The elastic-plastic finite element method (FEM) and the co.d deformation resistance model of Q235 steel were adopted in this model. Deformation uniformity of the final product has been analyzed using this model. The results indicate that the uniformity of the final product is obtained only as the centerline of the bending rolls is vertical to the centerline of the driven roll and parallel to the centerline of the drive roll in the whole rolling process. Besides, the number of the bending rolls must even realize the co.tinuous bending and reverse bending process. Also, the number of the bending rolls must match the deformation degree of the workpiece in the co.d rolling process. The validity of this finite element model was verified by the size and distribution of grains from the billet to the rebar in a practical co.d rolling process.

关键词： deformation uniformity Q235 steel rebar finite element method co.d rolling mechanical descaling

The Study on the Microstructure and Mechanical Properties of 400MPa Grade Bar Prepared by co.trolled co.ling After Finish Rolling

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Journal of Iron and Steel Research international 2011年第S1期18卷 610-614页

作者： ZHANG Jun-wei 1,DING Lei 1,XIAO Yi 2,3,HU Xiao-dong 1,HU Lin 1 (1.School of Materials and Metallurgy,University of Science and Technology Liaoning,Anshan 114051,Liaoning,china 2.Baosteel Nantong co.1},Nantong 226002,Jiangsu,china 3.School of Electrical engineering,Anhui University of Technology,Maanshan 243002,Anhui,china) Univ Sci & Technol Liaoning Sch Met & Mat Anshan 114051 Liaoning Peoples R China Baosteel Nantong co.ltd Nantong 226002 Jiangsu Peoples R China Anhui Univ Technol Sch Elect Engn Maanshan 243002 Anhui Peoples R China

The production process of bars in Baosteel Nantong *** adjusted by both decreasing heating temperature and adding co.trolling co.ling procedure after finish rolling for upgrade of bars.A set of water co.ling system was also installed behind the finishing ***-line tests were co.ducted,and then the microstructure and mechanical properties of the bars with HRB335 co.position and φ22mm diameter were *** results showed that the microstructures of the bar co.led by water were ferrite and pearlite with grain sizes of 8.5 to 12 grades,which were finer than that of the bar without water *** the thin outer layer microstructures of the bar co.led by water were mainly tempered sorbite with small amount of tempered *** average yield strength R eL and tensile strength R m of the bars with water co.ling increased 105MPa and 73MPa respectively co.pared with those of the bars without water *** reason of this strengthening was attributed to the synthetic role of fine grains and phase transformation and precipitation *** addition,The ration of R m /R eL co.ld be higher than 1.25,which is the request of earthquake-proof performance for HRB400E,only when the self-tempering temperatures of the bars were higher than 640℃.

关键词： co.trolled co.ling hot rolling bar fine grain strengthening self-tempering

ANALYSIS AND TREATMENT OF CRACKS ON OVERFLOW FACE co.CRETE IN TAIPINGWAN HYDROPOWER STATION DAM

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ANALYSIS AND TREATMENT OF CRACKS ON OVERFLOW FACE CONCRETE I...

international co.ference of Hydropower

作者： GUO Huimin Jiangsu Pumped Storage Power Generation ltd. co.

＜正＞The cracking on co.crete of overflow face is seldom seen. This paper analyzes the causes of cracking and introduces the treatment method. The dam has operated normally for 20 years and no abnormal phenomenon is ... 详细信息

关键词： Overflow face co.crete Cracks Analysis Treatment

Motion behavior of particles in air-solid magnetically stabilized fluidized beds for separation

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international Journal of Mining Science and Technology 2012年第5期22卷 725-729页

作者： Song Shulei a,,Zhao Yuemin a,Luo Zhenfu a,Tang Ligang b a School of Chemical engineering and Technology,china University of Mining & Technology,Xuzhou 221116,china b co.l Mining and Designing Department,Tiandi Science & Technology co.pany co.ltd.,Beijing 100013,china School of Chemical engineering and Technology China University of Mining & Technology Xuzhou 221116 China co.l Mining and Designing Department Tiandi Science & Technology Company Co. Ltd. Beijing 100013 China

In order to study the settling mechanism of particles in an air-solid magnetically stabilized fluidized bed(MSFB) for separation,we carried out free settling and quasi-zero settling tests on the tracing *** results show that the main resistance forces as the tracing particles settled in an air-solid MSFB were motion resistance force and yield *** motion resistance and yield forces greatly hindered the free settling of the particles by greatly decreasing the acceleration for settling process of the *** acceleration decreased from 3022.62 cm/s 2 to zero in 0.1 s,and in the end,the particles stopped in the air-solid *** yield force on particles increased with increasing the magnetic field intensity,resulting in decrease of the quasi-zero settling ***,the yield force on particles decreased with increasing the fluidized air velocity,leading to increase of the quasi-zero settling *** the structure and operating parameters of the air-solid MSFB were set up,the yield stress on particles stopped in an air-solid MSFB was a function of diameter and density of *** settling displacements of equal diameter particles increased with increasing their densities,and the settling displacements of equal density particles increased with increasing their diameters.

关键词： Air-solid MSFB Free settling Quasi-zero velocity settling Motion of particles