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Disturbance Rejection for Systems With Uncertainties Based on Fixed-Time Equivalent-Input-Disturbance Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第12期11卷 2384-2395页

作者： Qun Lu xiang wu Jinhua She Fanghong Guo Li Yu the School of Aeronautical Engineering Taizhou University the Zhejiang Dafeng Industry Co. Ltd. the Zhejiang Provincial United Key Laboratory of Embedded Systems Zhejiang University of Technology IEEE the School of Engineering Tokyo University of Technology

This paper presents a fixed-time equivalent-inputdisturbance(EID) approach to deal with the problem of robust output-feedback control for perturbed uncertain systems. This method uses the basic structure of the conventional EID approach and treats uncertainties and disturbances as a lumped disturbance on the control-input channel. A fixed-time state observer enables state estimation, which resolves the causality issue in an EID-based control system, is finished in a fixed time. An implicit Lyapunov function, the homogeneity with dilation, the input-tostate stability, and the small-gain theorem are used to analyze the convergence and robustness of the EID-based system with measurement noise. Numerical and experimental results are presented to demonstrate the effectiveness and superiority of the proposed method.

关键词： Disturbance rejection equivalent-input-disturbance (EID) approach fixed-time stability measurement noise output feedback control

On the Structure of Quantum Toroidal Superalgebraε_(m|n)

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Acta Mathematica Sinica,English Series 2023年第11期39卷 2117-2138页

作者： xiang Hua wu Hong Da LIN Hong Lian ZHANG Department of Mathematics Shanghai UniversityShanghai 200444P.R.China Newtouch Center for Mathematics of Shanghai University Shanghai 200444P.R.China

Recently the quantum toroidal superalgebraε_(m|n)associated with gl_(m|n)was introduced by *** and ***,which is not a quantum Kac-Moody *** quantum toroidal superalgebraε_(m|n)exploits infinite sequences of generators and relations of the form,which are called Drinfeld *** this paper,we use only finite set of generators and relations to define an associative algebraε'_(m|n)and show that there exists an epimorphism fromε'_(m|n)to the quantum toroidal superalgebraε_(m|n).In particular,the structure ofε'_(m|n)enjoys some properties like Drinfeld-Jimbo realization.

关键词： Quantum toroidal superalgebra Drinfeld realization Lie superalgebra

Flexible CuCo_(2)O_(4)@Ni-Co-S hybrids as electrode materials for high-performance energy storage devices

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Chinese Chemical Letters 2023年第3期34卷 512-517页

作者： Xiaowei Wang Yuchen Sun Wei-Chao Zhang xiang wu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China

Rational design of electrode meterials with unique core-shell nanostructures is of great significance for improving the electrochemical performance of supercapacitors. In this work, we prepare several CuCo_(2)O_(4)@Ni-Co-S composite electrodes by a controllable hydrothermal and electrodeposition route. Onedimensional nanowires can shorten the ions transport path, while two-dimensional nanosheets expose many active sites. This enables three-dimensional structured composite with high electrochemical activity. The as-prepared heterostructured materials show a specific of 1048 C/g at 1 A/g. It still maintains 75.6% of initial capacity after 20000 cycles at 10 A/g. The device delivers an energy density of 79.2 Wh/kg when the power density reaches to 2280 W/kg. Moreover, it possesses an excellent mechanical stability after repeated folding at different angles.

关键词： Core-shell structure CuCo_(2)O_(4)@Ni-Co-S Supercapacitor Energy density Mechanical stability

Rational Design of WO_3 Nanostructures as the Anode Materials for Lithium-Ion Batteries with Enhanced Electrochemical Performance

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Nano-Micro Letters 2015年第1期7卷 12-16页

作者： Yang Liu Yang Jiao Haiyue Zhou xiang Yu Fengyu Qu xiang wu Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of Education and College of Chemistry and Chemical Engineering Harbin Normal University

A facile, one-step hydrothermal method was employed to synthesize two kinds of WO3 nanostructures. By using different kinds of sylvine, tungsten trioxide(WO3) with different morphologies of microflowers and nanowires was obtained, respectively. The discharge capacities for microflowers and nanowires are 107 and 146 m Ah g-1 after 180 cycles, and their corresponding capacity retentions after the first cycle are 72 and 85 %, respectively. Even at a high current density of 1,600 m Ah g-1, the discharge capacities of WO3 microflowers and nanowires are as high as 433 and557 m Ah g-1 after 40 cycles, in which the current densities were increased stepwise. It is worth mentioned that the rate capability of the nanowires is superior to that of the microflowers. However, the cycle performance of the microflowers is better than nanowires, revealing that the morphology and structure of the as-synthesized WO3 products can exert great influence on the electrochemical performances.

关键词： WO3 nanostructures Anode materials Li-ion batteries

Thermal Equation of State of Natural F-Rich Topaz up to 29 GPa and 750 K

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Journal of Earth Science 2023年第3期34卷 758-766页

作者： Yungui Liu xiang Li Haipeng Song Jingui Xu Dongzhou Zhang Junfeng Zhang xiang wu State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China College of Gems and Materials Hebei GEO UniversityShijiazhuang 050031China Hawai'i Institute of Geophysics and Planetology School of Ocean and Earth Science and TechnologyUniversity of Hawaii at ManoaHonolulu HI 96822USA

Subducting oceanic sediments and crusts,originating from the Earth's surface and descending into its deep interior,are important carriers of *** volatiles have significant effects on materials cycling and the dynamic evolution of the subduction zones.A simplified Al_(2)O_(3)-SiO_(2)-H_(2)O(ASH)ternary system models the relationship of minerals in the hydrated and alumina-silica rich sedimentary *** Al_(2)SiO_(4)(F,OH)_(2)is an important mineral in the ASH system and comprises two volatiles:H_(2)O and fluorine(F).In this study,the thermoelasticity of a natural F-rich topaz was investigated using synchrotron-based single-crystal X-ray diffraction combined with diamond anvil cells up to 29.1 GPa and 750 *** pressure-volume-temperature data were fitted to a third-order Birch-Murnaghan Equation of state with V_(0)=343.15(7)Å3,K_(0)=166(1)GPa,K_(0)'=3.0(1),(∂K_(0)/∂T)P=-0.015(9)GPa/K andα_(0)=3.9(5)×10^(-5)K^(-1).The isothermal bulk modulus increases with the F content in topaz,and the various F contents present significant effects on its anisotropic *** results further reveal that the isothermal bulk modulus K_(0)of the minerals in ASH system increases with density.F and H contents in hydrous minerals might greatly affect their properties(e.g.,compressibility and stability),providing more comprehensive constraints on the subduction zones.

关键词： topaz hydrous mineral water fluorine subduction zones

Early-age strength property improvement and stability analysis of unclassified tailing paste backfill materials

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International Journal of Minerals,Metallurgy and Materials 2020年第9期27卷 1191-1202页

作者： Qian Zhou Juan-hong Liu Ai-xiang wu Hong-jiang Wang School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Urban Underground Space Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of High-Efficient Mining and Safety of Metal Ministry of EducationUniversity of Science and Technology BeijingBeijing 100083China

High-density tailings,small cementitious materials,and additives are used for backfill materials with poor early compressive strength(ECS),which may greatly affect the mining and backfill cycle,to prepare paste backfill materials(PBMs)with a high *** effects and mechanisms of different early strength agents on the property of PBM are *** action mechanism of additives on the properties of PBM is also analyzed through X-ray diffraction,scanning electron microscope,and energy dispersive *** show that the effects of single-component additives 1,3,and 6 are better than those of the other additives,and their optimal dosages are 3wt%,1wt%,and 3wt%,*** optimum multicomponent combinations are 1wt%of additive 1 and 1.5wt%of additive *** ECS of the paste with additive 10 increases to a greater extent than that of the other pastes because of the synergistic action of additive 1 with additive *** hydration product of Ca(OH)2 is consumed,and more C-S-H gels are generated with the addition of additives to *** particles,ettringite crystals,and gels intertwined with one another form a dense net-like structure that fills the *** structure can significantly improve the ECS of PBM.

关键词： paste backfill unclassified tailings binder powder early-age strength microstructure

Agglomeration and leaching behaviors of copper oxides with different chemical binders

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International Journal of Minerals,Metallurgy and Materials 2021年第7期28卷 1127-1134页

作者： Sheng-hua Yin Lei-ming Wang Xun Chen Ai-xiang wu Key Laboratory of the Ministry of Education of China for High-Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Department of Materials Engineering University of British Columbia309-6350 Stores RoadVancouverBC V6T 1Z4Canada

The chemical binder is one of the critical factors affecting ore agglomeration behavior and leaching *** this study,we in-vestigated the effect of the type of binder and mass fraction of the H_(2)SO_(4)solution used on the curing,soaking,and leaching behavior of *** results revealed that Portland cement(3CaO·SiO_(2),2CaO·SiO_(2),and 3CaO·Al_(2)O_(3))was the optimal binder for obtaining a well-shaped,stable agglomeration structure.A higher extraction rate was achieved when using Portland cement than that obtained using sodi-um silicate,gypsum,or acid-proof *** excessive geometric mean size is not conducive to obtaining well-shaped agglomerations and desirable *** computed tomography(CT)and MATLAB,the porosity of two-dimensional CT images in sample concentrations L1-L3 was observed to increase at least 4.5vol%after acid *** agglomerations began to be heavily destroyed and even to disinteg-rate when the sulfuric acid solution concentration was higher than 30 g/L,which was caused by the excessive accumulation of reaction products and residuals.

关键词： agglomeration binder acid leaching copper oxide sulfuric acid solution

Use of high-resolution X-ray computed tomography and 3D image analysis to quantify mineral dissemination and pore space in oxide copper ore particles

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International Journal of Minerals,Metallurgy and Materials 2017年第9期24卷 965-973页

作者： Bao-hua Yang Ai-xiang wu Guillermo A.Narsilio Xiu-xiu Miao Shu-yue wu Information Science and Engineering School Hunan International Economics UniversityChangsha 410205China Department of Infrastructure Engineering The University of MelbourneVictoria 3010Australia Key Laboratory of High-efficient Mining and Safety of Metal Mines(Ministry of Education) University of Science and Technology BeijingBeijing 100083China

Mineral dissemination and pore space distribution in ore particles are important features that influence heap leaching performance. To quantify the mineral dissemination and pore space distribution of an ore particle, a cylindrical copper oxide ore sample (I center dot 4.6 mm x 5.6 mm) was scanned using high-resolution X-ray computed tomography (HRXCT), a nondestructive imaging technology, at a spatial resolution of 4.85 mu m. Combined with three-dimensional (3D) image analysis techniques, the main mineral phases and pore space were segmented and the volume fraction of each phase was calculated. In addition, the mass fraction of each mineral phase was estimated and the result was validated with that obtained using traditional techniques. Furthermore, the pore phase features, including the pore size distribution, pore surface area, pore fractal dimension, pore centerline, and the pore connectivity, were investigated quantitatively. The pore space analysis results indicate that the pore size distribution closely fits a log-normal distribution and that the pore space morphology is complicated, with a large surface area and low connectivity. This study demonstrates that the combination of HRXCT and 3D image analysis is an effective tool for acquiring 3D mineralogical and pore structural data.

关键词： high-resolution X-ray computed tomography 3D image analysis ore particles mineral dissemination pore space

4-Amino-1,2,4-triazole Resin-supported Palladium Complex as Phosphine-free Catalyst for Suzuki Reaction in Aqueous Phase

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Chemical Research in Chinese Universities 2010年第2期26卷 331-334页

作者： wu xiang-mei WANG Yan GUO Sheng-rong College of Chemistry and Life Science Lishui University Lishui 323000 P. R. China

1 Introduction The Suzuki cross-coupling reaction is a powerful and versatile method for the generation of unsymmetrical biaryls from arylboronic acids and aryl halides in a single step. However, the reaction is usually performed in the presence of Pd catalyst along with phosphine ligand, which sometimes creates practical problems because organophosphines tend to be expensive, poisonous, and air sensitive. Recently, phos-phine-free ligands,

关键词： Suzuki reaction Phosphine-free ligand Palladium 4-Amino-1,2,4-triazole resin