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Relative Derived Equivalences and Relative Homological Dimensions

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Acta Mathematica Sinica,English Series 2016年第4期32卷 439-456页

作者： Sheng yong pan Department of Mathematics Beijing Jiaotong UniversityBeijing 100044P.R.China Beijing Center for Mathematics and Information Interdisciplinary Sciences Beijing 100048P.R.China

Let A be a small abelian *** a closed subbifunctor F of Ext_A^1（-,-）,Buan has generalized the construction of Verdier’s quotient category to get a relative derived category,where he localized with respect to F-acyclic *** this paper,the homological properties of relative derived categories are discussed,and the relation with derived categories is *** Artin algebras,using relative derived categories,we give a relative version on derived equivalences induced by F-tilting *** discuss the relationships between relative homological dimensions and relative derived equivalences.

关键词： Relative derived category F-tilting complex relative derived equivalence relative homological dimension

Convexity-preserving interpolation of trigonometric polynomial curves with a shape parameter

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第8期8卷 1199-1209页

作者： pan yong-juan WANG Guo-jin Department of Mathematics Zhejiang University Hangzhou 310027 China Department of Applied Mathematics Zhejiang University of Technology Hangzhou 310032 China

In computer aided geometric design(CAGD) ,it is often needed to produce a convexity-preserving interpolating curve according to the given planar data points. However,most existing pertinent methods cannot generate convexity-preserving in-terpolating transcendental curves;even constructing convexity-preserving interpolating polynomial curves,it is required to solve a system of equations or recur to a complicated iterative process. The method developed in this paper overcomes the above draw-backs. The basic idea is:first to construct a kind of trigonometric polynomial curves with a shape parameter,and interpolating trigonometric polynomial parametric curves with C2(or G1) continuity can be automatically generated without having to solve any system of equations or do any iterative computation. Then,the convexity of the constructed curves can be guaranteed by the appropriate value of the shape parameter. Performing the method is easy and fast,and the curvature distribution of the resulting interpolating curves is always well-proportioned. Several numerical examples are shown to substantiate that our algorithm is not only correct but also usable.

关键词： Computer aided geometric design (CAGD) α-trigonometric polynomial curves Interpolation Convexity-preserving Shape parameter

Mineral transition and formation mechanism of calcium aluminate compounds in CaO-Al2O3-Na2O system during high-temperature sintering

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International Journal of Minerals,Metallurgy and Materials 2020年第7期27卷 924-932页

作者： Hai-yan Yu Xiao-lin pan yong-pan Tian Gan-feng Tu School of Metallurgy Northeastern UniversityShenyang 110819China

The mineral transition and formation mechanism of calcium aluminate compounds in CaO-Al2O3-Na2O system during the hightemperature sintering process were systematically investigated using DSC-TG,XRD,SEM-EDS,FTIR,and Raman spectra,and the crystal structure of Na4Ca3(AlO2)10 was also simulated by Material Studio *** results indicated that the minerals formed during the sintering process included Na4Ca3(AlO2)10,CaO·Al2O3,and 12 CaO·7 Al2O3,and the content of Na4Ca3(AlO2)10 could reach 92 wt%when sintered at 1200°C for 30 *** main formation stage of Na4Ca3(AlO2)10 occurred at temperatures from 970 to 1100°C,and the content could reach82 wt%when the reaction temperature increased to 1100°*** crystal system of Na4Ca3(AlO2)10 was tetragonal,and the cells preferred to grow along crystal planes(110)and(210).The formation of Na4Ca3(AlO2)10 was an exothermic reaction that followed a secondary reaction model,and its activation energy was 223.97 kJ/mol.

关键词： calcium aluminate sodium oxide crystal structure formation kinetics sintering

Creep Behavior and Its Influence on the Mechanics of Electrodeposited Nickel Films

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Journal of Materials Science & Technology 2009年第1期25卷 90-94页

作者： Zengsheng Ma Shiguo Long yong pan Yichun Zhout Key Laboratory of Low Dimensional Materials ＆ Application Technology of Ministry of Education Faculty of Materials Optoelectronics and Physics Xiangtan University Xiangtan 411105 China

In order to improve the accuracy and comparability of hardness and elastic modulus measurements in nanoindentation, an evaluation of the creep behavior and its influence on the mechanical properties of the electrodeposited nickel film has been conducted. The influence of loading time and hold period on the hardness and elastic modulus results at maximum load 5000μN has also been examined. It is found that with increasing the loading time, the creep value is decreased. However, the creep value is increased when the hold period is increased. The elastic modulus results are more reliable if the hold period is longer. If the hold period is long enough, the loading time has no remarkable effect on the hardness and elastic modulus measured.

关键词： Nanoindentation Hardness Elastic modulus Creep

Confining sulfur in sandwich structure of bamboo charcoal and aluminum fluoride(BC@S@AlF3) as a long cycle performance cathode for Li-S batteries

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Journal of Materials Science & Technology 2020年第20期52卷 159-166页

作者： Zhenya Luo Xiao Wang Weixin Lei Pengtao Xia yong pan National-Provincial Laboratory of Special Function Thin Film Materials Xiangtan UniversityXiangtanHunan 411105China School of Materials Science and Engineering Xiangtan UniversityXiangtanHunan 411105China

The ’shuttle effect’ of polysulfide causing rapid capacity fade and low coulo mbic efficiency of high ene rgy storage lithium-sulfur(Li-S) ***,a sandwich structure of bamboo charcoal/sulfur coating by aluminum fluoride(BC@S@AlF3) composites is designed and fabricated for the first *** as-designed cathode exhibited excellent electrochemical properties and stable capacity *** initial capacity reaches 1119 mA h/g and the capacity after 100 cycles is 869 mA h/g at 0.5 C,which is much stable than that of composite materials without bamboo charcoal or AlF3 ***,the BC@S@AlF3 cathode presents excellent long-term capacity stability with a capacity decay of 0.073% per cycle during 500 charge/discharge cycles at 1 C,offering a potential for use in high energy Li-S *** physical confinement,chemical ancho ring,and catalysis conversion for active sulfur are achieved simultaneously with the AlF3 coating and bamboo charcoal core with porous structure.

关键词： AlF3 coating Strong polarity Sulfur immobilizers Lithium-sulfur batteries

Growth and Electronic Properties of Ag Nanoparticles on Reduced CeO2-x（111） Films

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Chinese Journal of Chemical Physics 2012年第6期25卷 713-718,I0004页

作者： Dan-dan Kong yong-he pan Guo-dong Wang Hai-bin pan Jun-fa Zhu National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei230029 China

Ag nanoparticles grown on reduced CeO2-x thin films have been studied by X-ray plhotoelec- tron spectroscopy and resonant photoelectron spectroscopy of the valence band to understand the effect of oxygen vacancies in the CeO2-x thin films on the growth and interracial elec- tronic properties of Ag. Ag grows as three-dimensional particles on the CeO2-x （111） surface at 300 K. Compared to the fully oxidized ceria substrate surface, Ag favors the growth of smaller particles with a larger particle density on the reduced ceria substrate surface, which can be attributed to the nucleation of Ag on oxygen vacancies. The binding energy of Ag3d increases when the Ag particle size decreases, which is mainly attributed to the final-state screening. The interracial interaction between Ag and CeO2_x（lll） is weak. The resonant enhancement of the 4f level of Ce3＋ species in RPES indicates a partial Ce4＋--＋Ce3＋ reduction after Ag deposited on reduced ceria surface. The sintering temperature of Ag on CeO 1.85 （111） surface during annealing is a little higher than that of Ag on CeO2 （111） surface, indicating that Ag nanoparticles are more stable on the reduced ceria surface.

关键词： Silver Ceria Growth Electronic structure X-ray photoelectron spectroscopy Resonant photoelectron spectroscopy

The Critical Group of Km × Cn

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Acta Mathematica Sinica,English Series 2011年第1期27卷 169-184页

作者： Jian WANG yong Liang pan Jun Ming XU Department of Mathematics University of Science and Technology of China Hefei 230026 P. R. China

In this paper, the structure of the critical group of the graph Km × Cn is determined, where m, n ≥3.

关键词： Graph Laplacian matrix critical group invariant factor Smith normal form tree number

Revealing sodium storage mechanism of hard carbon anodes through in-situ investigation of mechano-electrochemical coupling behavior

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Journal of Energy Chemistry 2023年第11期86卷 227-236,I0006页

作者： Mei Yang Zhenya Luo Xiao Wang Xinxin Cao Weiguo Mao yong pan Cuiying Dai Junan pan College of Materials Science and Engineering Xiangtan UniversityXiangtan 411105HunanChina College of Materials Science and Engineering Zhejiang UniversityHangzhou 310058ZhejiangChina College of Materials Science and Engineering Central South UniversityChangsha 410083HunanChina College of Materials Science and Engineering Changsha University of Science&TechnologyChangsha 410076HunanChina

Hard carbon(HC)is considered a promising anode material for sodium-ion batteries due to its relatively low price and high specific ***,HC still suffers from unclear reaction mechanisms and unsatisfactory cycling *** study of mechano-electrochemical coupling behavior by in-situ measurement techniques is expected to understand the sodium storage and degradation *** this paper,the strain and stress evolution of HC anodes at different sodiation/desodiation depths and cycles are investigated by combining electrochemical methods,digital image correlation,and theoretical *** observation by monitoring the in-situ strain evolution during the redox process supports the“adsorption-intercalation/filling”mechanism in reduction and the“de-filling/de-intercalation-deso rption”mechanism in *** studies have demonstrated that the strain and stress of the electrode show periodic changes accompanied by a continuous accumulation of residual stress during cycles,explaining the capacity degradation mechanism of HC from a mechanical *** addition,when the higher current density is applied,the electrodes experience greater strain and stress associated with the Na+insertion *** work clarifies the Na-storage mechanism and the mechano-electrochemical coupling mechanism of HC anodes by in-situ strain measurement,which helps optimize and design the anode materials of sodium-ion batteries from the perspective of interface microstructure and multi-field coupling,such as in situ integrated interface structure design.

关键词： Hard carbon Sodium storage In-situ strain measurement Digital image correlation Mechano-electrochemical coupling

Recent progress on optomagnetic coupling and optical manipulation based on cavity-optomagnonics

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Frontiers of physics 2022年第4期17卷 115-133页

作者： Kai Wang yong-pan Gao Rongzhen Jiao Chuan Wang School of Science and the State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China School of Electronic Engineering and the State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China School of Artificial Intelligence Beijing Normal UniversityBeijing 100875China

Recently,the photon–magnon coherent interaction based on the collective spins excitation in ferromagnetic materials has been achieved *** the prospect,the magnons are proposed to store and process quantum ***,cavity-optomagnonics which describes the interaction between photons and magnons has been developing rapidly as an interesting topic of the cavity quantum *** in this short review,we mainly introduce the recent theoretical and experimental progress in the field of optomagnetic coupling and optical manipulation based on *** to the frequency range of the electromagnetic field,cavity optomagnonics can be divided into microwave cavity optomagnonics and optical cavity optomagnonics,due to the different dynamics of the photon–magnon *** the interaction between the electromagnetic field and the magnetic materials is enhanced in the cavity-optomagnonic system,it provides great significance to explore the nonlinear characteristics and quantum properties for different magnetic *** importantly,the electromagnetic response of optomagnonics covers the frequency range from gigahertz to terahertz which provides a broad frequency platform for the multi-mode controlling in quantum systems.

关键词： optomagnetic coupling manipulation cavity-optomagnonics photon–magnon interaction