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LIMIT CYCLES AND BIFURCATION CURVES FOR THE QUADRATIC DIFFERENTIAL SYSTEM (III)_(m=0) HAVING THREE ANTI-SADDLES (I)

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Chinese Annals of Mathematics,Series B 1996年第2期17卷 167-174页

作者： ye yanqian Department of Mathematics, Nanjing University, Nanjing 210008, China. 南京大学数学系江苏南京

For the quadratic system: x=-y+δx + lx2 + ny2, y=x(1+ax-y) under conditions -10 the author draws in the (a, ()) parameter plane the global bifurcationdiagram of trajectories around O(0,0). Notice that when na2+l < 0 ... 详细信息

关键词： Quadrtic systen Anti-saddle Bifurcation curve Limit cycle

ANTI-SADDLES OF A POLYNOMIAL SYSTEM

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Chinese Annals of Mathematics,Series B 1995年第4期16卷 453-458页

作者： ye yanqian (Departmellt of Mathematics, Naming University, Naming 210008, China.) NANJING UNIV DEPT MATHNANJING 210008PEOPLES R CHINA

By using the generalized PoincarE index theorem it is proved that if the n2 critical points of an n-polynomial system form a configuration of type (2n -1) - (2n - 3) +(2n- 5) -…+ (- 1 )n- 1, and the 2n -1 outmost anti-saddles form the venices of a convex (2n -1)-polygon, then among these 2n-1 anti-saddles at least one must be a node.

关键词： Polynomial system Anti-saddle Poincare index theorem Equator.

SUPPLEMENT　TO“PASSAGE，BLOCKADE，SINK　AND　SOURCE　OF　A　PLANAR　DYNAMICAL　SYSTEMS”

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Chinese Annals of Mathematics,Series B 1994年第4期15卷 489-492页

作者： ye yanqian(Department of Mathematics, Nanjing University, Nanjing 210008,China.) 南京大学数学系江苏南京

A Theorem is given on the number of passages passing throgh a multiply-connected region,which corrects a wrong conjecture in a former paper of the author.

关键词： Passage Multiply-connected region Critical point Saddle point.

N3[1^3，2^2，3^3，…]的元素之间的线性关系

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南京大学学报（数学半年刊） 2004年第1期21卷 21-26页

作者：叶彦谦南京大学数学系，南京，210093

对N3[1^3，2^3，3^3，…]，1≤n≤200，除了1^3，2^3，3^3，4^3，5^3，7^3等6个数以外，我们得到只含4，5或6项的N3中具有不同元素的线性关系，使6，8，9，10，11，…，200分别是每一关系中的最大元素，并由此导出一个合理的猜想．此外... 详细信息

对N3[1^3，2^3，3^3，…]，1≤n≤200，除了1^3，2^3，3^3，4^3，5^3，7^3等6个数以外，我们得到只含4，5或6项的N3中具有不同元素的线性关系，使6，8，9，10，11，…，200分别是每一关系中的最大元素，并由此导出一个合理的猜想．此外，还得到6种不同类型的Diophantine不定方程的解组．

关键词： N3 线性关系丢番都方程猜想

Three-dimensional fracture of UO2 ceramic pellets by phase field modeling

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 169-180页

作者： Wei Xiong Xuan ye Hongzhang Cheng Xiaoming Liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

Fracture is the primary failure type for the UO2ceramic pellets,which are operated under irradiation and thermal processes,and physically confined by the *** this work,by combining closely coupled physical processes of heat conduction,heat transfer,and mechanical deformation with the cohesive phase field framework,we proposed a high-precision modeling of quasistatic cracking of three-dimensional （3D） UO2ceramic fuel pellets under high temperature and *** simulation results agree well with the experimental results,indicating that the proposed method has the potential to capture 3D crack modes in the interested time ***,we studied the relation of the 3D fracture patterns of fuel pellets with the peak power *** was found that the power level plays a critical role in determining the competition between radial and circumferential cracks,as well as transverse penetrating cracks.

关键词： phase field method nuclear fuel pellet coupled thermo-mechanical model thermal fracture

Prussian Blue Analogue‑Templated Nanocomposites for Alkali‑Ion Batteries:Progress and Perspective

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Nano-Micro Letters 2025年第1期17卷 216-261页

作者： Jian‑En Zhou Yilin Li Xiaoming Lin Jiaye ye Key Laboratory of Theoretical Chemistry of Environment Ministry of EducationSchool of ChemistrySouth China Normal UniversityGuangzhou 510006People’s Republic of China School of Chemistry and Physics Faculty of ScienceQueensland University of Technology2 George StreetBrisbaneQLD 4000Australia Centre for Materials Science Queensland University of Technology2 George StreetBrisbaneQLD 4000Australia

Lithium-ion batteries(LIBs)have dominated the portable electronic and electrochemical energy markets since their commercialisation,whose high cost and lithium scarcity have prompted the development of other alkali-ion batteries(AIBs)including sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs).Owing to larger ion sizes of Na^(+)and K^(+)compared with Li^(+),nanocomposites with excellent crystallinity orientation and well-developed porosity show unprecedented potential for advanced lithium/sodium/potassium *** enticing open rigid framework structures,Prussian blue analogues(PBAs)remain promising self-sacrificial templates for the preparation of various nanocomposites,whose appeal originates from the well-retained porous structures and exceptional electrochemical activities after thermal *** review focuses on the recent progress of PBA-derived nanocomposites from their fabrication,lithium/sodium/potassium storage mechanism,and applications in AIBs(LIBs,SIBs,and PIBs).To distinguish various PBA derivatives,the working mechanism and applications of PBA-templated metal oxides,metal chalcogenides,metal phosphides,and other nanocomposites are systematically evaluated,facilitating the establishment of a structure–activity correlation for these *** on the fruitful achievements of PBA-derived nanocomposites,perspectives for their future development are envisioned,aiming to narrow down the gap between laboratory study and industrial reality.

关键词： Prussian blue analogues Self-sacrificial template Lithium-ion batteries Sodium-ion batteries Potassium-ion batteries

Insight Into the Separation-of-Variable Methods for the Closed-Form Solutions of Free Vibration of Rectangular Thin Plates

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 329-355页

作者： Yufeng Xing ye Yuan Gen Li Institute of Solid Mechanics Beihang University(BUAA)Beijing100191China

The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical *** taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue ***,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are *** is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well.

关键词： Separation-of-variable method Rayleigh quotient nodal line eigenvalue equation bisection method

Netrin-1 signaling pathway mechanisms in neurodegenerative diseases

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Neural Regeneration Research 2025年第4期20卷 960-972页

作者： Kedong Zhu Hualong Wang Keqiang ye Guiqin Chen Zhaohui Zhang Department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina Department of Neurology The First Hospital of Hebei Medical UniversityBrain Aging and Cognitive Neuroscience Laboratory of Heibei ProvinceShijiazhuangHebei ProvinceChina Faculty of Life and Health Sciences Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina

Netrin-1 and its receptors play crucial roles in inducing axonal growth and neuronal migration during neuronal *** profound impacts then extend into adulthood to encompass the maintenance of neuronal survival and synaptic *** amounts of evidence highlight several key points:(1)Diminished Netrin-1 levels exacerbate pathological progression in animal models of Alzheimer’s disease and Parkinson’s disease,and potentially,similar alterations occur in humans.(2)Genetic mutations of Netrin-1 receptors increase an individuals’susceptibility to neurodegenerative disorders.(3)Therapeutic approaches targeting Netrin-1 and its receptors offer the benefits of enhancing memory and motor function.(4)Netrin-1 and its receptors show genetic and epigenetic alterations in a variety of *** findings provide compelling evidence that Netrin-1 and its receptors are crucial targets in neurodegenerative *** a comprehensive review of Netrin-1 signaling pathways,our objective is to uncover potential therapeutic avenues for neurodegenerative disorders.

关键词： Alzheimer’s disease axon guidance colorectal cancer Netrin-1 receptors Netrin-1 signaling pathways Netrin-1 neurodegenerative diseases neuron survival Parkinson’s disease UNC5C

The burden of upper motor neuron involvement is correlated with the bilateral limb involvement interval in patients with amyotrophic lateral sclerosis:a retrospective observational study

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Neural Regeneration Research 2025年第5期20卷 1505-1512页

作者： Jieying Wu Shan ye Xiangyi Liu Yingsheng Xu Dongsheng Fan Department of Neurology Peking University Third HospitalBeijingChina Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases BeijingChina Key Laboratory for Neuroscience National Health Commission/Ministry of EducationPeking UniversityBeijingChina

Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor *** bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to ***,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is *** address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral *** used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis *** factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb *** results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis *** findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis.

关键词： amyotrophic lateral sclerosis bilateral limb involvement Cox proportional hazards regression model horizontal spread restricted cubic spline analysis time interval upper motor neuron vertical spread