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Mechanical,expansion and rheological properties of circulating fluidized bed fly ash based ecological cement:A critical review

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International Journal of Minerals,Metallurgy and Materials 2022年第9期29卷 1670-1682页

作者： Wei Zhang xiaoming liu Zengqi Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

Circulating fluidized bed fly ash(CFBFA)is a solid waste product from circulating fluidized bed(CFB)boilers in power plants,and the storage of CFBFA is increasingly become an environmental *** scholars have made contributions to improve the resource utilization of ***,ecological cement is prepared by CFBFA,which is more conducive to its large-scale *** recent years,a lot of effort has been paid to improve the properties of ecological cement containing *** this work,the physicochemical properties of CFBFA are introduced,and recent research progress on the mechanical,expansion,and rheological properties of CFBFA based ecological cement(CEC)is extensively *** problem of over-expansion of f-CaO is summarized,which limits the scale application of CFBFA in ecological ***,the challenge for f-CaO in CFBFA to compensate for cement volume shrinkage is proposed,which is beneficial to the utilization of CFBFA in ecological cement,and the reduction of CO_(2) emissions from the cement *** addition,the environmental performance,durability,and economy of CEC should be valued in future research,especially the environmental performance,because the CFBFA contains heavy metals,such as Cr,As,which may pollute groundwater.

关键词： circulating fluidized bed fly ash ecological cement expansion durability compensation shrinkage

Numerical Simulation for Arc Windshields of Aircrafts Subjected to Bird Impact

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上海交通大学学报 2004年第z2期38卷 147-151页

作者： Yao Xiaohu Zhao Longmao liu xiaoming Institute of Applied Mechanics Taiyuan University of Technology China College of Traffic and Communications South China University of Technology China Institute of Applied Mechanics Taiyuan University of Technology China Chengdu Aircraft Industry Company China

A finite element model including full-scale circular arc windshield glass and the relative parts of the military plane is established in this paper. The model is analyzed by using an explicit element code LS-DYNA3D for analyzing the nonlinear dynamic response of structures. The data in aspects of displacement, strain, stress and contact force in the process of deformation are obtained. The deformation and failure mechanism of circular arc windshield glass are discussed. The possible location at which failure may take place is given. The valuable data are provided for designing,researching and producing new windshields with high crashworthiness.

关键词： bird impact arc windshield dynamic response liquid-solid coupling

Analysis of axially displaced elliptical antenna using hybrid method

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The Journal of China Universities of Posts and Telecommunications 2015年第6期22卷 51-56,93页

作者： liu xiaoming Yu Junsheng Chen Xiaodong School of Electronic Engineering Beijing University of Posts and Telecommunications School of Electronic Engineering and Computer Science Queen Mary University of London

Axially displaced elliptical （ADE） antenna is an evolved version of Gregorian antenna, bearing advantages of minimized blockage and relatively uniform field distribution. However, the analysis of the electrical performance of this type of antenna is a difficulty to be addressed properly. To enable the simulation of such type of reflector antenna, a hybrid method is derived for predicting the farfield of ADE antennas. Closed formulae are firstly derived for the calculation of the near field of ADE antennas based on vector analysis and the law of energy conservation. These formulae avoid time-consuming surface current integration and the current singularity on the vertex of the sub-reflector. In addition, the nature of vector analysis makes the hybrid method be capable of predicting vector electric field precisely. Furthermore, since these formulae are in explicit manner, no ray tracing process is required. The farfield is then predicted using Huygens equivalent method, assuring the accuracy in the farfield. Compared to published experimental results in the literature, the proposed method agrees well with the measurement in the main beam region. In comparison to physical optic method, the computational efficiency is much improved.

关键词： ADE antenna hybrid method Huygens equivalent method

Yielding behavior of copper nanowire in the presence of vacancies

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Science China(Physics,Mechanics & Astronomy) 2012年第6期55卷 1010-1017页

作者： liu xiaoming YANG XiaoBin WEI YueGuang The State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Resources and Safety Engineering China University of Mining&TechnologyBeijing 100083China

In the present research,the measurement fluctuations of mechanical properties in nanowires (NWs) are investigated by using the molecular dynamics *** large numbers of simulations are performed to study the yield behaviors of the *** results have shown that the yield behavior of the smaller diameter NW is more sensitive to the presence of vacancies,and the dispersion of the measured mechanical properties for the small scale NW is larger than that for the large scale *** results have also shown that vacancies escape from the bulk to the free surfaces as a result of high stress applied at the small scale systems similar to the dislocation starvation phenomenon observed in the compression test of nano-pillars,and dislocation nucleation induced by surface defect occurs after the vacancy reaches free surface leading to lower yield ***,the strong surface vacancy interactions at the nanoscale level are also investigated.

关键词： nanowire yield strength vacancies size effect

Robust entry guidance using multi-segment linear pseudospectral model predictive control

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Journal of Systems Engineering and Electronics 2017年第1期28卷 103-125页

作者： Liang Yang Wanchun Chen xiaoming liu Hao Zhou School of Astronautics Beihang UniversityBeijing 100191China

This paper presents a robust entry guidance algorithm for the high lift-to-drag ratio entry vehicle that employs the recently developed pseudospectral model predict control in a segmented manner. Here, the guidance commands are the longitudinal lift-to-drag (L/D) and bank reversal commands, which are calculated by successively solving multiple segment linear algebraic equations. These equations are derived using the linear pseudospectral method, control parametrization and calculus of variations. The method uses orthogonal polynomials and computes the updates through a series of analytical formulae, which makes it accurate and computationally effective. Moreover, it is able to adjust the number of bank reversals by providing the precise bank reversal point so as to fully exploit the potential of lateral maneuver. The method also employs proportional navigation and polynomial guidance after the last bank reversal to meet multiple terminal constraints. High-fidelity numerical simulations with various destinations are carried out to demonstrate its applicability. Furthermore, Monte Carlo simulations are also conducted to show that the proposed algorithm consistently offers very stable and robust performances and has superior performances in computational efficiency, guidance accuracy and lateral trajectory shaping capability in comparison with other typical methods. © 1990-2011 Beijing Institute of Aerospace Information.

关键词： Calculations Computational efficiency Drag Electronic guidance systems Intelligent systems Lift drag ratio Linear algebra Linear equations Monte Carlo methods

Hydrometallurgical detoxification and recycling of electric arc furnace dust

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International Journal of Minerals,Metallurgy and Materials 2023年第11期30卷 2076-2094页

作者： Yang Xue xiaoming liu Chunbao(Charles)Xu Yonghui Han State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Department of Chemical&Biochemical Engineering Western UniversityLondonON N6A 5B9Canada Hebei Technology Innovation Centre of Solid Wastes Utilization Hebei University of Science and TechnologyShijiazhuang 050091China

Electric arc furnace dust(EAFD)is a hazardous waste but can also be a potential secondary resource for valuable metals,such as Zn and *** the increased awareness of carbon emission reduction,energy conservation,and environmental protection,hydrometallurgical technologies for the detoxification and resource use of EAFD have been developing *** work summarizes the generation mechanisms,compositions,and characteristics of EAFD and presents a critical review of various hydrometallurgical treatment methods for EAFD,e.g.,acid leaching,alkaline leaching,salt leaching,and pretreatment–enhanced leaching ***,the phase transformation mechanisms of zinc-containing components in acid and alkali solutions and pretreatment processes are ***,two novel combined methods,i.e.,oxygen pressure sulfuric acid leaching combined with composite catalyst preparation,and synergistic roasting of EAFD and municipal solid waste incineration fly ash combined with alkaline leaching,are proposed,which can provide future development directions to completely recycling EAFD by recovering valuable metals and using zinc residue.

关键词： hazardous waste recycling separation zinc hydrometallurgical technologies

Thermodynamic evolution of lithosphere of the North China craton:Records from lower crust and upper mantle xenoliths from Hannuoba

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Chinese Science Bulletin 2003年第21期48卷 2371-2377页

作者： liu Yongsheng GAO Shan liu xiaoming CHEN xiaoming ZHANG Wenlan WANG Xuance Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China The State Key Lab for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 2 10093 China Key Laboratory of Continental Dynamics Department of GeologyNorthwest University Xi'an 710069 China

Major element compositions of garnet, clino-pyroxene, orthopyroxene and spinel in the garnet-bearing lower crust and upper mantle xenoliths from Hannuoba, North China craton are analyzed by the electron microprobe (EMP). The pressure-temperature estimates reveal the in-creasing temperature and pressure from core to rim for granulites. In contrast, mantle xenoliths with core tempera-ture > 930℃ recorded a history of decrease in temperature and pressure. However, those with core temperature < 930℃ show a negligible change. The final pressures recorded by these xenoliths cluster at 0.9—1.5 GPa. The presence of high- Na2O cpx in granulite xenoliths suggests that they are prod-ucts of the transition from granulite to eclogite metamor-phism corresponding to the increasing temperature and pressure. Together with previous studies, it is suggested that the P-T changes preserved in the xenoliths are related to lithospheric thickening and subsequent thinning prior to their eruption in the Cenozoic.

关键词：热力学中国北方地区岩石圈捕虏岩岩石层位学

Novel Concise Synthesis of （-）-Clausenamide1

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Chinese Journal of Chemistry 2013年第3期31卷 344-348页

作者： Di liu xiaoming Yu Liang Huang State Key Laboratory of Bioactive Substance and Function of Natural Medicine Beijing Key Laboratory of ActiveSubstance Discovery and Drugability Evaluation Institute of Materia Medica Chinese Academy of Medical Sci-ences & Peking Union Medical College Beijing 10050 China

A six-step synthesis of （-）-clausenamide is described. Optically pure （R,E）-1,3-diphenylallylic alcohol was ac-etylated and then subjected to an Ireland-Claisen rearrangement, giving the γ,δ-unsaturated acid, which underwent a substrate-induced stereoselective bromolactonization to afford the expected all-equatorial substituted bromo-δ-lac-one. An unusual chemo-selective aminolysis of the lactone resulted in the formation of a γ,δ-epoxy-amide in stereospecific manner. Base-promoted cyclization of this intermediate and the subsequent Davis oxidation furnished the synthesis, delivering the final product in 〉99% ee and up to 34% overall yield.

关键词： (-)-clausenamide diastereoselective synthesis Ireland-Claisen rearrangement diastereoselectivebromo|actonization bromo-c^-lactone aminolysis

Fast Cycle Structure Detection for Power Grids Based on Graph Computing

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CSEE Journal of Power and Energy Systems 2023年第6期9卷 2204-2213页

作者： Xinqiao Wang Kewen liu Weijiang Lu Ting Zhao Baohua Zhao xiaoming liu the Computing&Application Technology Research Division Global Energy Interconnection Research InstituteBeijing 102209China

The cycle structure in a power grid may lower the stability of the network;thus,it is of great significance to accu-rately and timely detect cycles in power grid ***,detecting possible cycles in a large-scale network can be highly time consuming and computationally *** addition,since the power grid's topology changes over time,cycles can appear and disappear,and it can be difficult to monitor them in real *** traditional computing systems,cycle detection requires considerable computational resources,making real-time cycle detection in large-scale power grids an impossible *** computing has shown excellent performance in many areas and has solved many practical graph-related problems,such as power flow calculation and state *** this article,a cycle detection method,the Paton method,is implemented and optimized on a graph computing *** cases are used to test its performance in an actual power grid topology *** results show that the graph computing-based Paton method reduces the time consumption by at least 60%compared to that of other methods.

关键词： Cycle detection graph computing power grid distribution grid