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Journal of Wuhan university of Technology(Materials Science) 2009年第6期24卷 940-944页

作者：张武满 school of Transportation Science and engineering Beihang University Jiangsu Key Laboratory of Construction Materials Southeast University

Hardened cement paste was subjected to the flexural loading and wet-dry cycles in sea water. The degradation of microstructures was obtained using scanning electron microscope （SEM）, and the energy dispersive spectrum （EDS） analysis was carried to analyze the local composition. Mercury intrusion porosimetry （Poremaster GT-60） was used to analyze the degradation of pore structures. The experimental results show that the synergistic action of the flexural loading, wet-dry cycles and sea water leads to significant deterioration of hardened cement paste. The degradation of microstructures in the tensile region is more serious than that in the compressive region. The flexural loading and wet-dry cycles accelerate the chemical attack of sea water.

关键词： hardened cement paste pore structure microstructures flexural loading wet-dry cycles sea water

Inverse Modeling of Nonlinear Systems and Application

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International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 302-305页

作者： Jianping Wei Huade Li Datai Yu(Information engineering school, university’ of Science and Technology’ Beijng, beijing 1 00083, china) Information engineering school University of Science and Technology Beijing Beijing 100083 China

Inverse modeling is discussed based on neural networks. U-D factorization Kalman filter learning algorithm is introduced totrain a feed forward multilayer neural network, which is used as inverse models. A scheme of D... 详细信息

关键词： neural network modeling control DC EAF

Dynamics and control of a solar collector system for near Earth object deflection

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Research in Astronomy and Astrophysics 2011年第2期11卷 205-224页

作者： Shen-Ping Gong,Jun-Feng Li and Yun-Feng Gao school of Aerospace,Tsinghua university,beijing 100084,china school of Aerospace Tsinghua University Beijing 100084 China

A solar collector system is a possible method using solar energy to deflect Earth-threatening near-Earth *** investigate the dynamics and control of a solar collector system including a main collector （MC） and secondary collector （SC）.The MC is used to collect the sunlight to its focal point,where the SC is placed and directs the collected light to an *** the relative position and attitude of the two collectors should be accurately controlled to achieve the desired optical ***,the dynamical equation of the relative motion of the two collectors in the vicinity of the asteroid is ***,the nonlinear sliding-mode method is employed to design a control law to achieve the desired configuration of the two ***,the deflection capability of this solar collector system is compared with those of the gravitational tractor and solar sail gravitational *** results show that the solar collector is much more efficient with respect to deflection capability.

关键词： minor planets asteroids -- techniques: miscellaneous -- solar collector

Observer Based Delay-Dependent Robust H∞ Control of Nonlinear Uncertain Systems with State and Input Delays

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Observer Based Delay-Dependent Robust H∞ Control of Nonline...

Influence of Mo on Dynamic Continuous Cooling Transformation of 1000 MPa Cold Rolled Dual Phase Steel

2011 Chinese Control and Decision Conference（CCDC）

作者： Miaoxin Wang is with the school of Control and Computer engineering,north china electric Power university,beijing,102206,china.Xinzhi Liu is with the Department of Applied Mathematics,university of Waterloo,Waterloo,Ontario,Canada,N2L3G1.Jizhen Liu is with the school of Control and Computer engineering,north china electric Power university,beijing,102206,china.Miaomiao Ma is with the school of Control and Computer engineering,north china electric Power university,beijing,102206,china

Observer-based delay-dependent robust H∞ controller design problem for state and input time-delays systems with a class of nonlinear uncertainties is discussed in this *** that the nonlinear uncertain functions in the considered model are gain-bounded,we obtain a sufficient condition for robustly asymptotic stability and H∞ performance of the closed-loop system in the light of Lyapunov stability *** solving a pair of linear matrix inequalities （LMIs）,we construct delay-dependent state feedback control law which guarantees robustly asymptotic stability of the closed-loop system and reduce the effect of the disturbance input on the controlled output to a prescribed *** delay-bounds and the H∞ performance bound can be optimized.A numerical example is given to illustrate our results.

关键词： Nonlinear uncertain systems State and input delays Delay-dependent Robust H∞ control Observer LMI

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Journal of Iron and Steel Research International 2011年第S1期18卷 296-299页

作者： ZHAO Xian-meng,KANG Yong-lin,HAN Qi-hang (school of Material Science and engineering.university of Science and Technology beijing,beijing 100083,china) Univ Sci & Technol beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

The expanding curves of two kinds of 1000 MPa ultra-high strength cold rolled dual phase steels,which were C-Si-Mn-Cr and C-Si-Mn-Cr-Mo steel respectively,were detected on Gleeble-1500 thermal-mechanical simulator at different cooling *** with metallographic and hardness methods,the continuous cooling transformation curves (CCT) of the two steels were *** results showed that Mo could raise the A r3 temperature,and strongly restrain the pearlite and bainite *** reason for this was the interaction that the addition of Mo could increase the chemical driving force of ferrite transformation and the activation energy for the diffusion of carbon in austenite,which could decelerate the ferrite *** hardness of the two steels was similar in the cooling rates range of this experiment and got higher with the increase of the cooling *** the cooling rates were above 7 ℃/s,the hardness almost kept constant because the most part of the microstructure was martensite.

关键词： Mo dual phase steel cold rolled CCT ultra-high strength

energy recovery and abatement potential of CO_2 emissions for an integrated iron and steel making enterprise

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Science china(Technological Sciences) 2010年第1期53卷 129-133页

作者： LI HongFu1,2,BAO WeiJun3,LI HuiQuan3 & CANG DaQiang1 1 Ecology and Recycling Metallurgy Laboratory,Ministry of Education,school of Metallurgical and Ecological engineering,university of Science and Technology beijing,beijing 10083,china 2 Jinan iron & Steel Group Ltd.,Jinan 250101,china 3 National engineering Laboratory for Clean Production Technology of Hydrometallurgy,Institute of Process engineering,Chinese Academy of Sciences,beijing 100190,china 1. Ecology and Recycling Metallurgy Laboratory Ministry of Education School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 10083 China2. Jinan iron & Steel Group Ltd. Jinan 250101 China3. National Engineering Laboratory for Clean Production Technology of Hydrometallurgy Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China

The typical features for an integrated iron & steelmaking industry are high energy consumption and CO2 *** traditional BF-BOF process in an integrated Iron and steelmaking enterprise produces a large amount of residual heat and energy,which has great potential for recovery and abatement potential of CO2 *** this paper,for an integrated Iron & steelmaking enterprise of 10 million tons per year in capacity,the residual heat and energy recovery analysis was *** is indicateded that the residual heat and energy can be recovered as electric power by using present advanced process *** means of the distributed power generation,the residual heat and energy can be recovered,with a power generation capacity of 419.5 kWh per ton steel ***,the abatement potential of CO2 emissions for an integrated iron & steel making enterprise was also evaluated,which indicated that about 398.5 kg CO2 could be reduced per ton steel product.

关键词： Iron and Steelmaking enterprise residual heat and energy recovery distributed power generation abatement potential of CO2 emission

In-situ TEM observation of microstructural evolution in 18Cr-ODS steel induced by electron beam irradiation

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Progress in Natural Science:Materials International 2012年第5期22卷 509-513页

作者： Guang Ran a,b,Shenghua Wu a,Zhangjian Zhou c,Rui Qiang a,Ning Li a,Lumin Wang a,b a school of energy Research,Xiamen university,Xiamen,Fujian 361005,china b Department of Nuclear engineering and Radiological Sciences,university of Michigan,Ann Arbor,MI 48109,USA c school of Materials Science and engineering,university of Science and Technology beijing,beijing,100083,china [a] school of energy Research Xiamen University Xiamen Fujian 361005 China [b] Department of Nuclear engineering and Radiological Sciences University of Michigan Ann Arbor MI 48109 USA [c] school of Materials Science and engineering University of Science and Technology Beijing Beijing 100083 China

The microstructural evolution behaviors of 18Cr-ODS steel under electron beam irradiation were in-situ investigated in a high resolution transmission electron microscopy(HRTEM).Fe3O4 particle was induced by electron beam irradiation through a series of dynamic procedures including lattice relaxation of the steel matrix,Cr and Ni segregations,combination of iron and oxygen atoms,epitaxial growth as well as separation of Fe3O4 *** size of oxides increased with increasing electron irradiation fluence,and it reached up to about 6 nm at the fluence of 6.1×1023e/cm2.

关键词： 18Cr-ODS steel Electron irradiation In-situ TEM Nuclear reactor

Numerical simulations of the bi-level and branched structure of intracloud lightning flashes

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Science china Earth Sciences 2006年第6期49卷 661-672页

作者： TAN Yongbo1, TAO Shanchang1, ZHU Baoyou1, MA Ming2 & LU Weitao2 1. school of Earth and Space Sciences, university of Science and Technology of china, Hefei 230026, china 2. Chinese Academy of Meteorological Sciences, beijing 100081, china 1. school of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China 2. Chinese Academy of Meteorological Sciences Beijing 100081 China

Intracloud (IC) lightning flashes have been simulated in fine resolution (12.5 m) by using a bidirectional stochastic lightning parameterization scheme within 2-dimensional domain. The simu-lated results show that the IC flashes have a bilevel channel structure and the altitudes of the hori-zontal channels are at the same heights of potential wells, which are supported by the previous VHF source observations and balloon soundings of electric field profile in the thundercloud. Further con-clusions are: (1) After an IC flash is initiated near the boundary between positve and nagetive charge zone, the negative (or positive) leader tends to propagate into the positive (or negative) charge zone. Both types of positive and negative IC flashes have been reproduced and their polarity depends on the up and down disposition of the positive and negative charge regions. (2) The extension range of leaders is correlative with the cloud charge distribution. The leader is possible to extend through the inverted charge region all over where it is extending, but keeps away from the isolated charge area of the same polarity. (3) The channel structures also depend on the electric potential distributions in the thundercloud. Before propagating into the central area of potential wells, the leader tends to extend along the direction with the maximum of potential gradient. Once extending away from the center of potential wells, the leader tends to extend along the direction with the slowest potential change. (4) The IC flash channels have the fractal feature with fractal dimension 1.45 before leaders pass through the central area of charge regions. The exponent decreases rapidly once leaders extend into the low-density charge regions. (5) The induced charges of opposite polarity are deposited in the leader channels within preexisting positive and negative charge regions during IC flash discharges. This causes a new and complicated charge distribution in the thundercloud, and the potential

关键词： IC, lightning parameterization, branched bilevel structure, fractal feature, propagation tendency.

Simulation on the Melt Flow in Laser Full Penetration Welding with a Model Including a Non-Rotational Symme-try Keyhole Based on energy Balance

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稀有金属材料与工程 2011年第S4期40卷 120-124页

作者： Zhang L J1,Zhang J X1,Wu B1,2,Chen L2,Gong S L2,Wang H R3 1 State Key Laboratory of Mechanical Behavior for Materials,Xi’an Jiaotong university,Xi’an 710049,china2 Power Beam Processing Dept.,Avic beijing Aeronautical Manufacturing Technology Research Institute,beijing 100024,china3 school of energy and Power engineering,Xi’an Jiaotong university,Xi’an 710049,china Xi An Jiao Tong Univ Sch Energy & Power Engn Xian 710049 Peoples R China Xi An Jiao Tong Univ State Key Lab Mech Behav Mat Xian 710049 Peoples R China Avic beijing Aeronaut Mfg Technol Res Inst Power Beam Proc Dept Beijing 100024 Peoples R China

A three dimensional model including a non-rotational symmetry keyhole of which the geometry is calculated base on the energy balance at keyhole wall is created to simulate the heat transfer and fluid flow within the molten pool during laser full penetration welding of titanium alloy *** order to take into account the effects of multiple reflections within the keyhole,a ray tracing method is employed and the coordinate dependent heat flux obtained is exerted on keyhole wall during the simulation on the heat transfer and fluid flow within molten ***,the computed weld cross sectional profile is compared with the experimental result to verify the model and it is fond that the simulation result is consists with experimental result.

关键词： laser welding titanium alloy non-rotational symmetry keyhole simulation

Modified Fuzzy Adaptive PID Algorithm and Its Application in Power Plant

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Modified Fuzzy Adaptive PID Algorithm and Its Application in...