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Comparative study on CO_2.corrosion behavior of N80,P110,X52.and 13Cr pipe lines in simulated stratum water

science china(Technological sciences) 2010年第9期53卷 2342-2349页

作者： CAI YiDong1,GUO PengChao1,LIU DaMeng1,CHEN ShiYu2.& LIU JunLai3 1 school of Energy Resources,china {2. of geosciences,beijing 100083.china 2.school of Materials science and engineering,{2. of science and technology beijing,beijing 100083.china 3 school of Earth sciences and Resources,china {2. of geosciences,beijing 100083.china 1. school of Energy Resources China University of Geosciences Beijing 100083 China2. School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China3. School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China

To better understand the carbon dioxide (CO2. corrosion behavior of carbon steel and its influence on petroleum development (including drilling,production and transportation) in the Daqing Oilfield,CO2.corrosion behaviors of N80,P110,X52.and 13Cr pipe lines in simulated solution at high temperature and high pressure condition are investigated by dynamic corrosion experiments,scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS) *** show that the corrosion rate of all pipe lines increases quickly when CO2.partial pressure increases from 0.5 to 1.5 MPa,but it slows down when CO2.partial pressure further increases from 1.5 to 4.5 MPa,during which localized corrosion is *** the experimental temperature ranges from 60 to 12.°C,localized corrosion *** corrosion rate of all pipe lines decreases sharply when the temperature changes from 60 to 100°C,and it becomes stable after the temperature is higher than 100°*** the flow rate is in the range of 0–1.5 m/s,the corrosion rate of sample X52.remains unchanged,but localized corrosion gradually becomes very serious when the flow rate further *** analyzing the corrosion product scales of sample 13Cr,some remarkable phenomena are *** the temperature range of 60–100°C,the corrosion product scales are loose and thick,but become very compact when the temperature increases above 100°*** the later case,localized corrosion is *** main components of the corrosion product scales are FeCO3 and Cr2.3.

关键词： CO2 corrosion pipe lines weight loss SEM EDS

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High Performance Speech Compression System

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Journal of university of science and {2. beijing 2001年第3期8卷 229-233页

作者： Ke Liu, Zhichun Mu, Zhong Wang Information engineering school, {2. of science & technology beijing, beijing 100083. china Univ Sci & Technol beijing Informat Engn Sch Beijing 100083 Peoples R China

Since Pulse Code Modulation emerged in 1937, digitized speech has experienced rapid development due to its outstanding voice quality, reliability, robustness and security in communication. But how to reduce channel width without loss of speech quality remains a crucial problem in speech coding theory. A new full-duplex digital speech communication system based on the Vocoder of AMBE-1000(TM) and microcontroller ATMEL 89C51 is introduced. It shows higher voice quality than current mobile phone system with only a quarter of channel width needed for the latter. The prospective areas in which the system can be applied include satellite communication, IP Phone, virtual meeting and the most important, defence industry.

关键词： digital signal processing digital speech compression digital communication full-duplex coding rate

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H~∞ Theory and its Application to the Position of Rolling Mill Control System

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 230-233页

作者： Jie Dong Chaonan Tong Kaixiang Peng(Information engineering school, {2. of science and technology beijing, beijing 100083. china) Information engineering school University of Science and Technology Beijing Beijing 100083 China

The controller designed according to classical or modern control theory will not satisfy the performance requirements when the controlled object in industrial field can not be described by exact mathematical model or the disturbance of the controlled system. In order to make the controlled system stable and having good performance, H∞ control theory was put forward to solve this practical problem. Taking the position of a rolling mill as the controlled object, it was rectified by optimal engineering way. Then, three different plans were put forward according to Bang-Bang control, LQ control and H∞ control, respectively. The result of the simulation shows that the controller designed according to H∞ method whose robust performance and ability to restrain colors disturbance is satisfactory.

关键词： position control H~∞ control LQ control Bang-Bang controll

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Prediction and Control of both Wrinkle Limit and Fracture Limiton Cylindrical Cup Deep-drawing(Ⅱ)

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 201-204页

作者： Junxiang Lei Yonglin Kang(Department of Mechanical engineering, Yantai university, Yantai 2.4005, {2.)(Material science and engineering school, university of science and technology beijing, beijing 100083. china) Department of Mechanical engineering Yantai University Yantai 264005 China Material science and engineering {2. University of Science and Technology Beijing Beijing 100083 China

The prediction and control criterion of both the wrinkle limit and fracture limit on the cylindrical cup deep-drawing are given, and the prediction and control diagram of both the wrinkle limit and fracture limit are also given. The results show that it is suitable for no-flange cylindrical cup deep-drawing, narrow-flange cylindrical cup deep-drawing, wide-flange cylindrical cup deep-drawing/expanding compound forming and rigid punch expanding forming.

关键词： cylindrical cup wrinkle limit fracture limit deep-drawing expanding forming compound forming

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Effects of Na/K ratio on the phase structure and electrical properties of Na_xK_(1-x)NbO_3 lead-free piezoelectric ceramics

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Rare Metals 2010年第2期29卷 220-225页

作者： ZHANG Qian, ZHANG Boping, Li Haitao, and SHANG Pengpeng school of Materials science and {2., university of science and technology beijing, beijing 100083. china school of Materials science and {2. University of Science and Technology Beijing

Lead-free piezoelectric NaxK1-xNbO3（x = 0.3-0.8）（NKN） ceramics were fabricated by normal sintering at 1060°C for 2.*** and electrical properties of the ceramics were investigated with a special emphasis on the influence of Na *** grain size of the produced dense ceramic was decreased by increasing Na content.A discontinuous change in the space distance was found at the composition close to Na0.7K0.3NbO3 ceramic, which indicates the presence of a transitional composition between two different orthorhombic phases, which is similar to the behavior of morphotropic phase boundary（MPB） in NaxK1-xNbO3 *** MPB-like behavior contributes to the enhanced piezoelectric coefficient d33 of 12. pC/N, planar-mode electromechanical coupling coefficient kP of 2..6%, and dielectric constant εr of 703, respectively for the Na0.7K0.3NbO3 *** temperature TC and the transitional temperature TO-T from orthorhombic to tetragonal phase are observed at around 42.°C and 2.0°C, respectively.

关键词： lead-free piezoelectric ceramics NKN sintering morphotropic phase boundary(MPB)

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Nonequilibrium Thermodynamic and Dissipative Structure Mechanism of Fluidized Beds

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 90-93页

作者： Maozhan Qi Li Wang Xuezi Ni (Mechanical engineering school, {2. of science and technology beijing, beijing 100083. china) Mechanical engineering school University of Science and Technology Beijing Beijing 100083 China

Fluidized beds are nonlinear dynamic systems that exchange mass and energy with outside. They are governed not only byfluid dynamics, but by thermodynamics, especially the second law of thermodynamics as well. According to Prigogine's dissipative structure theory, the following have been concluded: (l) a fixed bed is on thermodynamic blanch, and bubbling, turbulent and fast beds areon the dissipatve structure branches. (2. Entropy in fluidized beds is divided into tWo parts: entropy production and entropy flux. The latter increases with gas velocity and decreases with pressure of the systems. That means the entropy of a system may reduce and the systemwith higher gas velocity behaves as dissipative structure characteristics. (3) For a giVen velocity, a fluidized bed operates stably on thewhole, but it is unstable to local gas-solid phases. The unstable phases are described by fluid dynamic equations, While the minimum ofsystem energy function assures whole stability of the system. (4) A transition criterion of a bubbling bed is derived from Prigogine's stability theory.

关键词： fluidized bed nonequilibrium thermodynamics dissipative structure energy extremum

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Synthetical Control of AGC/LPC System Based on Neural Networks Internal Model Control

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Journal of university of science and {2. beijing 2001年第1期8卷 75-77页

作者： Hu He, Xiaodong Luan, Yikang Sun Information engineering school, {2. of science and technology beijing, beijing 100083. china Univ Sci & Technol beijing Informat Engn Sch Beijing 100083 Peoples R China

One synthetical control method of AGC/LPC system based on intelligence control theory-neural networks internal model control method is presented. Genetic algorithm (GA) is applied to optimize the parameters of the neu... 详细信息

关键词： hot strip rolling AGC looper neural networks internal model control GA

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Water-affinity of Perlite Products and Its Anti-water Mechanism after Being Modified

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 196-198页

作者： Cunyi Song Wen Ni Deping Chen(Resources engineering school, {2. of science and technology beijing, beijing, 100083. china) Resources engineering school University of Science and Technology Beijing Beijing 100083 China

The structure modification and its mechanism have been studied when perlite products changed from water-affinity state to anti-water state. The structure of fused perlite and its surface physicochemical properties have also been studied. The modification of perlite products has provided the products with anti-water property, which not only enhanced the quality of thermal insulating function, reduced the lost of heat energy, but also made the products water-proof These modified perlite products are used as ideal thermal insulating layers for the thermodynamic equipment and heat transporting conducts.

关键词： water-affinity anti-water property perlite surface sodification

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Short-term load forecasting based on fuzzy neural network

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International Journal of Minerals,Metallurgy and Materials 1997年第3期11卷 46-48,53页

作者： DONG Liang MU Zhichun (Information engineering school, {2. of science and technology beijing, beijing 100083. china) Univ of science and technology Beijing Beijing China

The fuzzy neural network is applied to the short-term load forecasting. The fuzzy rules and fuzzy membership functions of the network are obtained through fuzzy neural network learming. Three inference algorithms, i.e. themultiplicative inference, the maximum inference and the minimum inference, are used for comparison. The learningalgorithms corresponding to the inference methods are derived from back-propagation algorithm. To validate the fuzzyneural network model, the network is used to Predict short-term load by compaing the network output against the realload data from a local power system supplying electricity to a large steel manufacturer. The experimental results aresatisfactory.

关键词： short-term load forecasting fuzzy control fuzzy neural networks

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Mechanical Property and Microstructural Characterization of C-Mn-Al-Si Hot Dip Galvanizing TRIP Steel

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Journal of Iron and Steel Research International 2012年第8期19卷 29-36页

作者： JIANG Hai-tao1, DING Wei1,2. TANG Di1, HUANG Wei1 (1. National engineering Research Center for Advanced Rolling technology, {2. of science and technology beijing, beijing 100083. china 2. school of Material and Metallurgy, Inner Mongolia {2. of science and technology, Baotou 014010, Inner Mongolia, china) [a] National engineering Research Center for Advanced Rolling technology University of Science and Technology Beijing Beijing 100083 China [b] school of Material and Metallurgy Inner Mongolia University of Science and Technology Baotou 014010 Inner Mongolia China

Mechanical properties and microstructure in high strength hot dip galvanizing TRIP steel were investigated by optical microscope (OM), transmission electron microscope (TEM), X-ray diffraction (XRD), dilatometry and mechanical testing. On the heat treatment process of different intercritical annealing (IA) temperatures, isothermal bainitic transformation (IBT) temperatures and IBT time, this steel shows excellent mechanical properties with tensile strength over 780 MPa and elongation more than 2.%. IBT time is a crucial factor in determining the mechanical properties as it confirms the bainite transformation process, as well as the microstructure of the steel. The microstructure of the hot dip galvanizing TRIP steel consisted of ferrite, bainite, retained austenite and martensite during the short IBT time. The contents of ferrite, bainite, retained austenite and martensite with different IBT time were calculated. The results showed that when IBT time increased from 2. to 60 s, the volume of bainite increased from 14.31% to 16.95% and the volume of retained austenite increased from 13.64% to 16.2.%; meanwhile, the volume of martensite decreased from 7.18% to 1.89%. Both the transformation induced plasticity of retained austenite and the hardening of martensite are effective, especially, the latter plays a dominant role in the steel containing 7.18% martensite which shows similar strength characteristics as dual-phase steel, but a better elongation. When martensite volume decreases to 1.89%, the steel shows typical mechanical properties of TRIP, as so small amount of martensite has no obvious effect on the mechanical properties.

关键词： TRIP steel isothermal bainitic transformation martensite mechanical property

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