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Chinese Journal of Polymer Science 2021年第7期39卷 849-855页

作者： Xiao-Lan Qiao Jie Yang Lian-He Han Ji-Dong Zhang mei-fang zhua State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Poly(3-hexylthiophene)(P3HT)thin films,obtained by normal spin-coating and solvent vapor assisted spin-coating(SVASP)before and after thermal annealing(TA),and the corresponding devices were prepared to unravel the microstructure-property relationship,which is of great importance for the development of organic *** SVASP-TA films were used as the active layers of the organic field-effect transistors,a hole mobility up to 0.38 cm^(2)·V^(-1)·s^(-1)was *** mobility was one of the highest values and one order of magnitude higher than that of the normal spin-coating films based *** relationship between the microstructure and the device performance was fully investigated by UV-Vis absorption spectra,grazing incident X-ray diffraction(GIXD),and atomic force microscopy(AFM).The impressive mobility was attributed to the high crystallinity and ordered molecule packing,which stem from the synergistic effects of SVASP and thermal annealing.

关键词： Poly(3-hexylthiophene) Polymer field-effect transistors Microstructure Polymer semiconductors

Perfect Matching in k-partite k-graphs and 3-uniform HM-bipartite Hypergraphs

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Acta Mathematicae Applicatae Sinica 2020年第3期36卷 636-641页

作者： Chun-qiu fang mei LU Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

Let H=(V,E)be an n-balanced k-partite k-graph with partition classes V1,...,*** for every legal(k-1)-tuple f contained in V\V1 and for every legal(k-1)-tuple g contained in V\Vk such that f∪g■E(H),we have d(f)+d(g)≥n+*** this paper,we prove that under this condition H must have a perfect *** result of this paper is about the perfect matching in 3-uniform hm-bipartite *** G be a 3-uniform hm-bipartite hypergraph with one of whose sides V1 has the size n,the another side V2 has size 2 *** for all the legal 2-tuple f with|f∩V1|=1 and for all the legal 2-tuple g with|g∩V1|=0,we have d(f)≥n-2 and d(g)>n/2,then G has a perfect matching.

关键词： Perfect matching k-partite k-graph hm-bipartite hypergraph

Two Interacting Electrons in a Vertically Coupled Quantum Dot

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Communications in Theoretical Physics 2004年第4期41卷 619-622页

作者： XIEWen-fang WANGAn-mei SchoolofScience GuangzhouUniversityGuangzhou510405China

We study a two-electron system in a double-layer quantum dot under a magnetic field by means of the exact diagonalization of the Hamiltonian *** find that discontinuous ground-state energy transitions are induced by an external magnetic field in the case of strong ***,in the case of weak coupling,the angular momentum L of the true ground state does not change in accordance with the change of the magnetic field B and remains L=0.

关键词： quantum dot few-body physics

Preparation of Zirconia-Ceria Powders with High Specific Surface Area

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Journal of Rare Earths 2004年第z1期22卷 46-48页

作者： Wang Enguo mei fang Department of Physics Zhanjiang Normal University Zhanjiang 524048 China Department of Physics Zhanjiang Normal University Zhanjiang 524048 China

Zirconia-ceria mixed oxide powders were prepared by high temperature aging *** effects of the temperature and the time of aging, cerium content and calcination on powder performance were *** result shows that high temperature aging is an efficient way of preparation of ZrO2-CeO2 mixed oxide powders with high specific surface area and good thermal stability, and that addition of a small amount of cerium to hydrous zirconia can promote the preparation of high specific surface area powders.

关键词： zirconia ceria high temperature aging high specific surface area rare earths

Catalytic Behavior of CO Oxidization over Pd/ZrO2 - CeO2 Catalyst

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Journal of Rare Earths 2004年第z1期22卷 185-187页

作者： Wang Enguo mei fang Department of Physics Zhanjiang Normal University Zhanjiang 524048 China Department of Physics Zhanjiang Normal University Zhanjiang 524048 China

The effects of Pd loading, cerium content, the special surface area of the support and calcination temperature on the catalytic properties of Pd-loaded zirconia-ceria mixed oxide were *** results show that loading Pd and increasing cerium content in the mixed oxides can enhance the catalytic *** is a little effect of calcination temperature on catalytic activities, implying that these catalysts are effective with good thermal stability.

关键词： mixed oxide CO oxidation ceria zirconia palladium rare earths

Mean square stability for Markov jump Boolean networks

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Science China(Information Sciences) 2020年第1期63卷 190-199页

作者： Liqing WANG mei fang Zheng-Guang WU State Key Laboratory of Industrial Control Technology Institute of Cyber-Systems and ControlZhejiang University College of Automation Harbin Engineering University

In this paper, one of the stability definitions of Markov jump Boolean networks(MJBNs), called mean square stability(MSS), is investigated. Some necessary and sufficient conditions are presented to guarantee the MSS of such MJBNs. Moreover, one of the necessary and sufficient conditions for MSS is obtained in terms of linear programming, which implies that MSS is equivalent to global stability with probability 1 for MJBNs. Furthermore, the construction of Lyapunov function is given and also another theorem based on the Lyapunov function is derived to ensure the MSS of MJBNs. Finally, a numerical example is provided to illustrate the profits of our results.

关键词： mean square stability MSS Boolean network BN stochastic stability Markovian jump parameters semi-tensor product STP Lyapunov function

Ground State Transitions in Vertically Coupled Four-Layer Single Electron Quantum Dots

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Communications in Theoretical Physics 2005年第1X期44卷 183-187页

作者： WANGAn-mei XIEWen-fang DepartmentofPhysics GuangzhouUniversityGuangzhou510405China

We study a four-electron system in a vertically coupled four-layer quantum dot under a magnetic field by the exact diagonalization of the Hamiltonian matrix. We find that discontinuous ground-state energy transitions are induced by an external magnetic field. We find that dot-dot distance and electron-electron interaction strongly affect the low-lying states of the coupled quantum dots. The inter-dot correlation leads to some sequences of possible disappearances of ground state transitions, which are present for uncoupled dots.

关键词：量子理论四层量子点磁场 Hamiltonian矩阵

Determination of Scaling Parameter and Dynamical Resonances in Complex-Rotated Hamiltonian Ⅰ:Theory

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Communications in Theoretical Physics 2008年第3期49卷 599-606页

作者： ZHAO fang ZHAO mei-Shan Department of Mathematics and Department of Chemistry The University of Chicago Chicago Illinois 60637 USA The James Pranck Institute and Department of Chemistry The University of Chicago Chicago Illinois 60637 USA

In this paper we present a theoretical analysis on the determination of the scaling parameter in the complex-rotated Hamiltonian, which has served as a basis for successful applications of the rigged Hilbert space theory for resonances. Based on the complex energy eigenvalue, E（θ） = ER（θ） - iГ（θ）/2, as a function of the scaling parameter θ, we find that for potential barrier scattering, the condition dГ（θI）/dθ = 0 uniquely determines the scaling parameter 8. The condition d ER （θR）/ dθ = 0 is merely a consequence of the Virial theorem and θI =θR is not a necessary condition for a resonance state. We also provide a harmonic approximation formMism for resonances in scattering over a potential barrier.

关键词： complex-rotated Hamiltonian potential scattering resonances rigged Hilbert space

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An automated method for glacial lake mapping in High Mountain Asia using Landsat 8 imagery

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Journal of Mountain Science 2018年第1期15卷 13-24页

作者： ZHANG mei-mei CHEN fang TIAN Bang-sen Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences No. 9 Dengzhuang South Road Beijing 100094 China University of Chinese Academy of Sciences Beijing 100049 China Hainan Key Laboratory of Earth Observation Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences Sanya 572029 China

Glacial lakes in the High Mountain Asia(HMA)are sensitive to global warming and can result in much more severe flood disasters than some largesized *** accurate and robust method for the extraction of glacial lakes is critical to effective management of these natural water *** methods often have limitations in terms of low spectral contrast and heterogeneous backgrounds in an *** study presents a robust and automated method for the yearly mapping of glacial lake over a large scale,which took advantage of the complementarity between the modified normalized difference water index(MNDWI)and the nonlocal active contour model,required only local homogeneity in reflectance features of *** cloud computing approach with the Google Earth Engine(GEE)platform was used to process the intensive amount of Landsat 8 images from 2015 (344 path/rows and approximately 7504 scenes).The experimental results were validated by very high resolution images from Chinese GaoFen-1 (GF-1) panchromatic multi-spectral(PMS)and appeared a general good *** is the first time that information regarding the spatial distribution of glacial lakes over the HMA has been derived automatically within quite a short period of *** integrating it with the relevant indices,it can also be applied to detect other land cover types such as snow or vegetation with improved accuracy.

关键词： Glacial lake Landsat 8 Modified Normalized Difference Water Index Nonlocal active contour

Genetic basis and biotechnological manipulation of sexual dimorphism and sex determination in fish

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Science China(Life Sciences) 2015年第2期58卷 124-136页

作者： mei Jie GUI Jian-fang College of Fisheries Key Laboratory of Freshwater Animal Breeding Ministry of Agriculture Freshwater Aquaculture Collaborative Innovation Center of Hubei Province Huazhong Agricultural University State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences University of the Chinese Academy of Sciences

Aquaculture has made an enormous contribution to the world food production,especially to the sustainable supply of animal *** utility of diverse reproduction strategies in fish,such as the exploiting use of unisexual gynogenesis,has created a typical case of fish genetic breeding.A number of fish species show substantial sexual dimorphism that is closely linked to multiple economic traits including growth rate and body size,and the efficient development of sex-linked genetic markers and sex control biotechnologies has provided significant approaches to increase the production and value for commercial *** with the rapid development of genomics and molecular genetic techniques,the genetic basis of sexual dimorphism has been gradually deciphered,and great progress has been made in the mechanisms of fish sex determination and identification of sex-determining *** review summarizes the progress to provide some directive and objective thinking for further research in this field.

关键词： reproduction strategies sexual dimorphism sex determination sex-determining gene sex chromosome sex controlbreeding