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Science China(Information Sciences) 2021年第2期64卷 192-201页

作者： Pengying CHANG Gang DU xiaoyan LIU Institute of Microelectronics Peking University

Polarization evolution with space and time in HfO2based metal-ferroelectric-insulator-metal（MFIM） structure is studied based on the phase field model by self-consistently solving the two-dimensional time-dependent Ginzburg-Landau and Poisson equations. Through examining the domain wall and electrostatic（depolarization） energies compared with the negative ferroelectric（FE） anisotropy energy, the correlation between the domain pattern（phase transition） and negative capacitance（NC） effect is revealed for different structure parameters and material properties, including FE thickness and gradient coefficient,dielectric permittivity and thickness, and operation frequency of applied voltage. The design space for stabilized NC with（near） hysteresis-free operation accompanied with voltage amplification is limited by phase transition, implying the potentials and limitations of FE HfO2for energy-efficient steep-slope devices.

关键词： ferroelectric polarization dynamics hysteresis negative capacitance depolarization field

Cotorsion Pairs in CN（A）

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Algebra Colloquium 2017年第4期24卷 577-602页

作者： xiaoyan Yang Tianya Cao Department of Mathematics Northwest Normal University Lanzhou 730070 China

Given a cotorsion pair （X, Y） in an abelian category A, we define cotorsion pairs （XN,dgYN） and （dgXN, YN） in the category CN（A） of N-complexes on A. We prove that if the cotorsion pair （X, Y） is complete and hereditary in a bicomplete abelian category, then both of the induced cotorsion pairs are complete, compatible and hereditary. We also create complete cotorsion pairs （dwXN, （dwXN）⊥）, （eXXN, （exXN）⊥） and （⊥（dwYN）, dwYN）, （X（exYN）, exYN） in a termwise manner by starting with a cotorsion pair （X,Y） that is cogenerated by a set. As applications of these results, we obtain more abelian model structures from the cotorsion pairs.

关键词： N-complex cotorsion pair model structure Hovey pair

Synthesis of a sulfur-graphene composite as an enhanced metal-free photocatalyst

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Nano Research 2013年第4期6卷 286-292页

作者： Wenchao Peng xiaoyan Li Environmental Engineering Research Centre Department of Civil Engineering The University of Hong Kong Pokfulam Hong Kong China

A novel metal-free photocatalyst--sulfur/graphene （S/GR） composite--has been synthesized using a facile one-pot, two-step hydrothermal method with thiosulfate and graphene oxide （GO） as precursors. A green reductant--L-ascorbic add--was used to transform GO to GR under mild conditions. The photocatalyst powders were characterized by Fourier transform infrared spectroscop, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and energy dispersive spectroscopy. Experimental tests were conducted on the photocatalytic decomposition of methyl orange （MO） by different catalysts. Compared to pure oL-S, the as-prepared S/GR composite showed much enhanced photocatalytic activity for the degradation of MO under both UV and solar light. The presence of GR also greatly increased the hydrophilicity and adsorption capacity of the catalyst material. The results indicate that the incorporation of GR with a-S results in a synergistic effect for the S-based photocatalysts offering more effective environmental applications.

关键词： metal-free catalyst a-sulfur graphene photocatalysis methyl orange organic degradation

Further study on Horozov-Iliev's method of estimating the number of limit cycles

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Science China Mathematics 2022年第11期65卷 2255-2270页

作者： xiaoyan Chen Maoan Han Department of Computer Science and Mathematics Changsha UniversityChangsha 410022China Department of Mathematics Zhejiang Normal UniversityJinhua 321004China

In the study of the number of limit cycles of near-Hamiltonian systems,the first order Melnikov function plays an important *** paper aims to generalize Horozov-Iliev’s method to estimate the upper bound of the numbe... 详细信息

关键词： near-Hamiltonian system piecewise smooth system Melnikov function limit cycle

Distributed energy trading with transmission cost: a Stackelberg game approach

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Science China(Information Sciences) 2021年第2期64卷 249-251页

作者： xiaoyan ZHANG Shanying ZHU Department of Automation Shanghai Jiao Tong University Key Laboratory of System Control and Information Processing Ministry of Education of China

Dear editor,Distributed generation combines different renewable energy sources at the edge of the grid, such as wind and solar *** helps manage energy demand more efficiently and further relax the stress on the grid if these energy sources are properly utilized. This can be mainly realized by engaging the end-users to actively participate in energy trading.

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Proteomics of spermatogenesis： from protein lists to understanding the regulation of male fertility and infertility

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Asian Journal of Andrology 2011年第1期13卷 18-23页

作者： xiaoyan Huang Jiahao Sha Lab of Reproductive Medicine Department of Histology and Embryology Nanjing Medical University Nanjing 210029 China

Proteomic technologies have undergone significant development in recent years, which has led to extensive advances in protein research. Currently, proteomic approaches have been applied to many scientific areas, including basic research, various disease and malignant tumour diagnostics, biomarker discovery and other therapeutic applications. In addition, proteomics-driven research articles examining reproductive biology and medicine are becoming increasingly common. The key challenge for this field is to move from lists of identified proteins to obtaining biological information regarding protein function. The present article reviews the available scientific literature related to spermatogenesis. In addition, this study uses two-dimensional electrophoresis mass spectrometry （2DE-MS） and liquid chromatography （LC）-MS to construct a series of proteome profiles describing spermatogenesis. This large-scale identification of proteins provides a rich resource for elucidating the mechanisms underlying male fertility and infertility.

关键词： infertility male fertility proteomics spermatogenesis

Substantial study on the occupation development of gender equality

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International Journal of Mining Science and Technology 2012年第5期22卷 625-628页

作者： Zhang xiaoyan School of Management China University of Mining & Technology Xuzhou 221116 China Xuzhou College of Industrial and Vocational Technology Xuzhou 221140 China

Men and women participate in many social activities through professional *** main content of this study is the occupation development gender equality,which is a recessive change of ***,we cannot concretely measure it to some extent,but through the structure square distance model and employees' feeling about the process,we can reflect its *** results of studying the feelings of male and female employees show that the gender equality is a problem,and there is a difference for men and women in career development.

关键词： Occupation development Equality Substantial evidence research

Investigation and analysis of network psychology of college students

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International Journal of Mining Science and Technology 2013年第2期23卷 199-203页

作者： Zhang xiaoyan School of Management China University of Mining & Technology Xuzhou College of Industrial Technology

Based on basic situational research and analysis carried out on 638 college students using network, we found that as many as 20 percent of the students are not only largely dependent on internet, but also addicted to it. Further biography characteristics analyses for different individuals on the four dimensions of the network forced addiction, tolerance, and time management and interpersonal relationship and health, show that there are significant differences in grades, gender with different education levels of their parents. Further researches on discrepancy that addicted groups have in network entertainment addiction, network information, cyber porn, network relations and network transactions addictions also illustrate that significant discrepancies exist in gender, net age, different discipline and other factors. Finally we put forward some correlative measures to solve the problems of college students network psychology from individuals, schools, and society levels.

关键词： College student Network psychology Investigation and analysis Factor

A new skeleton based flying bird detection method for low-altitude air traffic management

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Chinese Journal of Aeronautics 2018年第11期31卷 2149-2164页

作者： Tianhang WU xiaoyan LUO Qunyu XU School of Electronic and Information Engineering Beihang University Image Processing Center School of AstronauticsBeihang University Department of Civil and Environmental Engineering University of Illinois

In low-altitude air traffic management, non-cooperation targets are the greatest threat to security of low-flying aircraft. Among various aviation fatalities, flying bird is the main factor with the highest risk and directs economic losses amounted to nearly 10 billion US dollars each ***, Flying Bird Detection(FBD) has attracted considerable attention in low-altitude air traffic management. In this paper, we propose a skeleton based FBD method via describing bird motion information with a set of key poses. To overcome the variability of birds, the skeleton feature is selected as a relatively fixed and common characteristic for the pose appearance of flying bird. Based on the geometric topology among some key parts of bird body, a set of key poses can be described by some extracted skeleton features, which are used to represent the bird motion information. Aimed at robustly handling with the pose variations, multiple pose-specific classifiers are individually trained to learn the representative poses of the flying bird. At the detection stage,the flying bird skeleton features are combined with extracted key-pose sets to perform the flying bird classification task from each image. Afterwards, the key-frame pose-change set and the consistency of the classification results from sequent images are employed to validate the final detection *** on flying bird datasets demonstrate the effectiveness and efficiency of the proposed method.

关键词： Bird-aircraft collisions Flight security Flying bird detection Low-Altitude Air Traffic Management(LAATM) Simplified skeleton descriptor

Implications from γ-globulin adsorption onto cation exchangers fabricated by sequential alginate grafting and sulfonation

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Chinese Journal of Chemical Engineering 2021年第1期34卷 121-125页

作者： Xianxiu Li Yan Sun xiaoyan Dong Department of Biochemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300354China Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education) Tianjin UniversityTianjin 300072China

Our previous work proved that high adsorption capacity and uptake rate of lysozyme were achieved on alginate(Alg)-grafted re sin with an ionic capacity(IC) of 240 mmol·L^(-1)(Alg-FF-240).Moreover,the salt-tolerant feature of Alg-FF-230 was improved by using sequential alginate grafting and sulfonation *** by the enhanced adsorption performance of lysozyme,we have herein proposed to investigate the static and dynamic adsorption behaviors of γ-globulin on a series of Alg-grafted resins with different grafting densities and sulfonation *** adsorption ca pacity of γ-globulin decreased with increa sing alginate-grafting density(IC) from 160 to 230 mmol·L^(-1) at 0 mmol·L^(-1) NaCl because of the steric hindrance caused by the alginate-grafting *** of ionic strength(IS) indicated that the adsorption capacities of the resins with the IC value of 230-370 mmol·L^(-1) were much higher than CM Sepharose FF at 50-100 mmol·L^(-1) NaCl,and the uptake rate of Alg-FF-230 was about twice as much as that of CM Sepharose *** work demonstrated the important effects of alginate-grafting layer and IS in γ-globulin adsorption behavior,which would be helpful in the design of Alggrafted resins and the selection of proper IS condition for protein purification.

关键词： Alginate Sulfonation γ-Globulin Adsorption capacity Uptake rate