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The Cathaysia Flora and the Mixed Late Permian Cathaysian-Angaran Floras in East Asia

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Journal of Integrative Plant Biology 2006年第4期48卷 381-389页

作者： ke-Qin sun State key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of the Ministry of Education China University of Geosciences Beijing 100083 China

The Cathaysla flora, one of the most prominent floras of the Carboniferous and Permian, was mainly distributed In East Asia and was characterized by numerous endemic elements. China Is one of the most Important localities of the Cathaysla flora and It ;s also the center of origin of this flora. This paper reviews and discusses the characteristics of the Cathaysla flora and the blogeographlcally mixed Permian Cathayslan-Angaran floras of East Asia. In addition, the formative mechanism of the mixed Permian floras Is also discussed.

关键词： Cathaysia flora East Asia mixed floras Permian.

Existence of p-mean Almost Periodic Mild Solution for Fractional Stochastic Neutral Functional Differential Equation

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Acta Mathematicae Applicatae Sinica 2021年第3期37卷 645-656页

作者： Xiao-ke sun Ping HE School of Mathematics Shanghai University of Finance and EconomicsShanghai200433China

A class of fractional stochastic neutral functional differential equation is analyzed in this *** the utilization of the fractional calculations,semigroup theory,fixed point technique and stochastic analysis theory,a sufficient condition of the existence for p-mean almost periodic solution is obtained,which are supported by two examples.

关键词： p-mean almost periodic solution fractional stochastic neutral functional differential equation fixed point theorem sectorial operator analytic semigroup

Composite disturbance attenuation based saturated control for maintenance of low Earth orbit (LEO) formations

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第5期13卷 328-338页

作者： Jian-cheng FAN ke sun National key Laboratory of Inertial Technology Beihang University Beijing 100191 China Novel Inertial Instrument & Navigation System Technology key Laboratory of Fundamental Science for National Defense Beihang University Beijing 100191 China

Maintenance of high performance formation control is important for low Earth orbit (LEO) formation missions of small *** this paper,a model of nonlinear relative motion dynamics is built,and then nonlinear and important perturbations affecting the formation configuration,such as J 2 and atmospheric drag,are analyzed as *** navigation satellite system based relative positioning with nonlinear filtering is adopted to provide state information associated with the *** combining disturbance observer based control with H ∞ state feedback,a composite disturbance attenuation controller is proposed for maintenance of continuous and accurate *** consideration of precise control relying on micro thrusters,a composite disturbance attenuation based saturated controller is designed and its stability is ***,through numerical simulations,we demonstrate that control accuracy is improved after effectively avoiding perturbations and that stabilization can be satisfied using this method.

关键词： Formation maintenance Perturbation Disturbance attenuation H ∞ state feedback Saturated control

Effect of sintering process on microstructure and magnetic properties of high frequency power ferrite

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Rare Metals 2006年第z1期25卷 509-514页

作者： sun ke LAN Zhongwen CHEN Shengming sun Yueming YU Zhong State key Laboratory of Electronic Thin Films and Integrated Devices UESTCChengdu 610054China Jiangsu Research Center of Magnetic Materials and Devices Engineering and Technology Wuxi 214199China

An oxide ceramic process was adopted to prepare high frequency manganese-zinc(MnZn)power *** combination with the microstructure analysis of material,the influences of sintering process on initial permeability(μ_(i))and high frequency loss in unit volume(P_(cv))of MnZn power ferrite were *** results show that in order to obtain fine microstructure and high frequency properties,the preferable sintering temperature and atmosphere are 1230℃and oxygen partial pressure(P_(O_(2)))of 4%,respectively.

关键词： manganese-zinc ferrite microstructure initial permeability sintering process

Orientation distribution of fibers and rheological property in fiber suspensions flowing in a turbulent boundary layer

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Acta Mechanica Sinica 2008年第3期24卷 243-250页

作者： Jian Zhong Lin ke sun Weifeng Zhang China Jiliang University Hangzhou 310018 China Department of Mechanics Zhejiang UniversityHangzhou 310027 China Institute of Marine and Coastal Sciences Rutgers UniversityNew Brunswick N J USA

A model relating the translational and rotational transport of orientation distribution function （ODF） of fibers to the gradient of mean ODF and the dispersion coefficients is proposed to derive the mean equation for the ODE Then the ODF of fibers is predicted by numerically solving the mean equation for the ODF together with the equations of turbulent boundary layer flow. Finally the shear stress and first normal stress difference of fiber suspensions are obtained. The results, some of which agree with the available relevant experimental data, show that the most fibers tend to orient to the flow direction. The fiber aspect ratio and Reynolds number have significant and negligible effects on the orientation dis- tribution of fibers, respectively. The additional normal stress due to the presence of fibers is anisotropic. The shear stress of fiber suspension is larger than that of Newtonian solvent, and the first normal stress difference is much less than the shear stress. Both the additional shear stress and the first normal stress difference increase with increasing the fiber concentration and decreasing fiber aspect ratio.

关键词： Turbulent fiber suspensions Fiber orientation Rheological property Boundary layer Numericalsimulation

Intermetallic interphases in lithium metal and lithium ion batteries

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InfoMat 2021年第10期3卷 1083-1109页

作者： ke sun Zhangquan Peng Laboratory of Advanced Spectro-electrochemistry and Li-ion Batteries Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianChina School of Applied Physics and Materials Wuyi UniversityJiangmenChina Tianmu Lake Institute of Advanced Energy Storage Technologies Co.Ltd. LiyangChina

A robust electrode-electrolyte interface is the cornerstone for every battery system,as demonstrated in the meandering history of the development of Li-ion batteries(LIBs).In the thrust to replace the graphite anode with more energetic ones in LIBs,the effectual strategy for stabilizing the original graphite-electrolyte interface becomes obsolete and a new anode-electrolyte interface needs ***,this interface has become the Achilles'heel for those anodes,such as Li-metal anode(LMA)and Si-based anode owing to their excessive reductivity,enormous volume change,and so ***,in the last decade,impressive progress has been made on taming these extremely unstable interfaces and on the solid-state batteries(SSBs)that are reported to be less susceptible to parasitic *** of the distinguished strategies is the application of artificial Li-alloying intermetallic interphases onto the surface of LMA,via the direct introduction of foreign metals to the Li anode or indirect hetero-cations doping in the electrolyte,to regulate the Li deposition/stripping behavior,which has markedly improved the stability of the LMA-electrolyte *** parallel,the intermetallic interphases are also witnessed to profoundly enhance the anode-solid electrolyte contact and the corresponding charge transfer kinetics in various *** review will provide a panoramic overview of the application of the intermetallic interphases at the anode-electrolyte interfaces in the lithium metal batteries(LMBs),SSBs,and also derivative works in the conventional LIBs,which will focus on different concepts,methodologies,and understandings from the encircled studies.

关键词： anode-electrolyte interface intermetallic interphase Li-alloying interphase lithiophilic interphase lithium metal anode

Microstructure and magnetic performance of Ni-substituted high density MnZn ferrite

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Rare Metals 2006年第z1期25卷 584-587页

作者： YU Zhong LAN Zhongwen CHEN Shengming sun Yueming sun ke State key Laboratory of Electronic Thin Films and Integrated Devices UESTCChengdu 610054China Jiangsu Research Center of Magnetic Materials and Devices Engineering and Technology Wuxi 214199China

The effects of NiO on microstructure and magnetic properties of Mn-Zn ferrite with a nominal composition of Zn_(0.32)Mn_(0.60-x)Ni_(x)Fe_(2.08)O_(4)were *** calcined powder of Mn-Zn ferrite was characterized by X-ray diffraction(XRD),the fracture surface of Mn-Zn ferrite was checked by scanning electronic microscope(SEM),and then the magnetic properties were *** a result,the substitution of Ni can cause the crystal lattice constant of MnZn ferrite to decline,and the grain size to decrease,therefore improve the magnetic performance of MnZn ferrite whose density exceeds 5.0 g·cm^(-3).

关键词： MnZn ferrite Ni-substitution microstructure magnetic performance

User Decision-based Analysis of Urban Electric Vehicle Loads

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CSEE Journal of Power and Energy Systems 2021年第1期7卷 190-200页

作者： Lei Dong Chunfei Wang Mengting Li ke sun Tianyi Chen Yingyun sun the State key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(North China Electric Power University) Changping DistrictBeijing 102206China the State Grid Economic and Technological Research Institute Co. Ltd.

The grid load attributable to electric vehicles (EVs)is affected by the choice behaviors of EV users. To analyze theeffects of factors such as travel demand and electricity priceson user behavior, a logit discrete choice model is introducedto simulate the users decisions to charge/travel. Based on aquasi-steady-state traffic network, a model for cluster electricvehicles considering the user’s behavior is designed to obtain theprobability distribution of the user’s behavior and the chargeand discharge curves of cluster EVs under various scenarios. Thevalidity of the proposed model is verified using an IEEE 9-nodetraffic network case and an urban traffic network case. Furthermore,the impact of the electricity price, traffic conditions, andother factors on the load curves of urban EVs is analyzed.

关键词： Cluster electric vehicles discrete choice model quasi-steady traffic network model vehicle-to-grid(V2G)

Eulerian-Lagranigan simulation of aerosol evolution in turbulent mixing layer

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Applied Mathematics and Mechanics(English Edition) 2016年第10期37卷 1305-1314页

作者： Kun ZHOU Xiao JIANG ke sun Zhu HE The State key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Clean Combustion Research Center King Abdullah University of Science and Technology

The formation and evolution of aerosol in turbulent flows are ubiquitous in both industrial processes and nature. The intricate interaction of turbulent mixing and aerosol evolution in a canonical turbulent mixing layer was investigated by a direct numerical simulation （DNS） in a recent study （Zhou, K., Attili, A., Alshaarawi, A., and Bisetti, F. Simulation of aerosol nucleation and growth in a turbulent mixing layer. Physics of Fluids, 26, 065106 （2014））. In this work, Monte Carlo （MC） simulation of aerosol evolution is carried out along Lagrangian trajectories obtained in the previous simulation, in order to quantify the error of the moment method used in the previous simulation. Moreover, the particle size distribution （PSD）, not available in the previous works, is also investigated. Along a fluid parcel moving through the turbulent flow, temperature and vapor concentration exhibit complex fluctuations, triggering complicate aerosol processes and rendering complex PSD. However, the mean PSD is found to be bi-modal in most of the mixing layer except that a tri-modal distribution is found in the turbulent transition region. The simulated PSDs agree with the experiment observations available in the literature. A different explanation on the formation of such PSDs is provided.

关键词： turbulent mixing layer aerosol dynamics Monte Carlo (MC) simulation