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Periodic Variation Studies of the Two Short Period W UMa-type Eclipsing Binaries: LX Lyn and V0853 Aur

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Research in Astronomy and Astrophysics 2024年第1期24卷 273-284页

作者： xu Zhang Bin Zhang School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550025China

In this paper,new light curves(LCs) of contact eclipsing binary(CEB) systems LX Lyn and V0853 Aur are presented and analyzed by using the 2015 version of the Wilson-Devinney(W-D) *** order to explain their asymmetric LCs,cool starspots on the components were *** is suggested that their fill-out degrees are f=12.0%(LX Lyn) and f=26.3%(V0853 Aur).At the same time,we found that LX Lyn is a W-type eclipsing binary(EB) with an orbital inclination of i=84°.88 and a mass ratio of q=2.31.V0853 Aur is also a W-type CEB with a mass ratio of q=2.77 and an orbital inclination of i= 79°.*** on all available times of light minimum,their orbital period changes are studied by using the O-C *** O-C diagram of LX Lyn reveals a cyclic oscillation with a period of about 14.84 yr and an amplitude of 0.0019 days,which can be explained by the light-travel time effect(LTTE) due to the presence of a third body with a minimum mass of0.06M_⊙.For V0853 Aur,it is discovered that the O-C diagram of the system also shows a cyclic oscillation with a period of 9.64 yr and an amplitude of 0.03365 *** cyclic oscillation of V0853 Aur can be attributed to the LTTE by means of a third body with a mass no less than 3.77M_⊙.The third body may play an important role in the formation and evolution of these systems.

关键词： stars:activity (stars:)binaries(including multiple):close (stars:)binaries:eclipsing (stars:)brown dwarfs stars:evolution stars:formation

Bio-inspired inorganic-protein coating on Mg-based biomaterials for bioengineering applications

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Science China Materials 2024年第5期67卷 1678-1680页

作者： xuwen Peng Haolan xu Department of Chemistry Engineering Tsinghua UniversityBeijing100084China Department of Chemical and Materials Engineering University of AlbertaEdmontonAlbertaT6G 1H9Canada Future Industries Institute UniSA STEMUniversity of South AustraliaMawson Lakes CampusAdelaideSouth Australia5095Australia

Developing smart and advanced functional materials inspired by the unparalleled complexity and efficiency of biological tissues has received much attention across various *** alloys,particularly pure magnesium,have emerged as notable candidates in orthopedics and dentistry due to their exceptional biocompatibility,degradability,and ability to promote bone regeneration[1].However,the highly reactive chemical nature of magnesium and its rapid degradation upon exposure to water.

关键词： coating alloys magnesium

Magnetic and electrical transport study of the intrinsic magnetic topological insulator MnBi_(2)Te_(4)with Ge doping

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Frontiers of physics 2024年第3期19卷 51-59页

作者： Qingwang Bai Mingxiang xu School of Physics Southeast UniversityNanjing 211189China

As an intrinsic magnetic topological insulator with magnetic order and non-trivial topological structure,MnBi_(2)Te_(4)is an ideal material for studying exotic topological states such as quantum anomalous Hall effect and topological axion insulating ***,we carry out magnetic and electrical transport measurements on(Mn1–xGex)Bi_(2)Te_(4)(x=0,0.15,0.30,0.45,0.60,and 0.75)single *** is found that with increasing x,the dilution of magnetic moments gradually weakens the antiferromagnetic exchange ***,Ge doping reduces the critical field of ferromagnetic ordering,which may provide a possible way to implement the quantum anomalous Hall effect at lower magnetic *** transport measurements suggest that electrons are the dominant charge carriers,and the carrier density increases with the Ge doping ***,the Kondo effect is observed in the samples with x=0.45,0.60,and *** results suggest that doping germanium is a viable way to tune the magnetic and electrical transport properties of MnBi_(2)Te_(4),opening up the possibility of future applications in magnetic topological insulators.

关键词： MnBi_(2)Te_(4) intrinsic magnetic topological insulator transition points Kondo effect

Near-Field Heat Transfer Enhancement of SiC-hBN-InSb Thermophotovoltaic System by Graphene Strong Coupling Effects

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Journal of Thermal Science 2024年第4期33卷 1409-1420页

作者： xu Zhiguo HU Zhifang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240China

Near-field thermophotovoltaic(NTPV)devices comprising a SiC-hBN-graphene emitter and a graphene-InSb cell with gratings are designed to enhance the performance of the NTPV *** electrodynamics and rigorous coupled-wave analysis are employed to calculate radiative heat transfer *** is found that the NTPV systems with two graphene ribbons perform better due to the graphene strong coupling *** effects of graphene chemical potential are *** is demonstrated that near-field radiative heat transfer of thermophotovoltaic devices is enhanced by the coupling of surface plasmon polaritons,surface phonon polaritons,hyperbolic phonon polaritons,and magnetic polaritons caused by the graphene strong coupling *** splitting frequency of different polaritons is calculated to quantify the mutual interaction of graphene strong coupling ***,the effects of cell grating filling ratio are *** excitation of magnetic polaritons is affected by the graphene ribbon and the cell filling *** investigation provides a new explanation of the enhancement mechanism of graphene-assisted thermophotovoltaic systems and a novel approach for improving the output power of the near-field thermophotovoltaic system.

关键词： near-field radiative heat transfer thermophotovoltaics strong coupling effect multiple magnetic polaritons graphene-hbn heterostructures

Tracked robot with underactuated tension-driven RRP transformable mechanism:ideas and design

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Frontiers of Mechanical Engineering 2024年第1期19卷 85-104页

作者： Ran xu Chao LIU School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Key Laboratory of Vehicle Advanced Manufacturing Measuring and Control Technology(Ministry of Education)Beijing Jiaotong UniversityBeijing 100044China

Robots with transformable tracked mechanisms are widely used in complex terrains because of their high adaptability,and many studies on novel locomotion mechanisms have been conducted to make them able to climb higher *** underactuated transformable mechanisms for tracked robots could decrease the number of actuators used while maintaining the flexibility and obstacle-crossing capability of these robots,and increasing their cost ***,the underactuated tracked robots have appreciable research *** this paper,a novel tracked robot with a newly proposed underactuated revolute‒revolute‒prismatic(RRP)transformable mechanism,which is inspired by the sit-up actions of humans,was *** newly proposed tracked robot has only two actuators installed on the track pulleys for moving and does not need extra actuators for ***,it could concentrate the track belt’s tension toward one side,and the unbalanced tension would drive the linkage mechanisms to change its *** this method,the proposed underactuated design could change its external shape to create support points with the terrain and move its center of mass actively at the same time while climbing obstacles or crossing other kinds of terrains,thus greatly improving the climbing capability of the *** geometry and kinematic relationships of the robot and the crossing strategies for three kinds of typical obstacles are *** the basis of such crossing motions,the parameters of links in the robot are designed to make sure the robot has sufficient stability while climbing ***-crossing dynamic simulations were run and analyzed to prove the feasibility of the robot.A prototype was built and *** show that the proposed robot could climb platforms with heights up to 33.3%of the robot’s length or cross gaps with widths up to 43.5%of the robot’s length.

关键词： mechanical design tracked robot underactuated mechanisms RRP mechanism obstacle crossing strategy

Effect of Skeleton Grain Size on the Saturation of Gas Hydrate in Natural Sediments

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Journal of Ocean University of China 2024年第3期23卷 676-682页

作者： xu Zhenqiang LI Yang College of Marine Sciences Ocean University of ChinaQingdao 266100China China Petroleum&Chemical Corporation Beijing 100728China

Natural gas hydrate is prospected as a new and promising,highly clean energy resource that mainly occurs in perma-frost or at continental *** formation is subject to many soil conditions,such as grain size,matrix materials,pore morphology,and *** this study,we propose that grain size is the most decisive parameter that affects the saturation of gas hydrate in sediments based on data from Ocean Drilling Program Leg 164 and Mallik 5L-38,which represent marine sediments and terrestrial sediments,*** study reveals that high gas hydrate saturation generally occurs in coarse-grained sand,regardless of whether sediment formation is homogeneous or inhomogeneous,and the sorting of sediments may affect the hydrate saturation to a certain *** grain size and sorting of sediments may be the most intuitive proxy method for a rough estimation of hydrate *** study is necessary to fully understand the relationship between hydrate morphology and sediment grain size,even though massive hydrates are typically found in fine clayey-rich sediments.

关键词： grain size saturation gas hydrates ODP Leg 164 Mallik 5L-38

Single-Nucleus RNA Sequencing Reveals Cardiac Macrophage Landscape in Hypoplastic Left Heart Syndrome

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Congenital Heart Disease 2024年第2期19卷 233-246页

作者： Xiaozhuo xu Yilin Huang xu Han First Clinical Medical College Affiliated Hospital of Nanjing University of Chinese MedicineNanjing210008China Department of Geriatrics Affiliated Hospital of Nanjing University of Chinese MedicineNanjing210029China

Background:Hypoplastic left heart syndrome(HLHS)is one of the most challenging congenital heart diseases in clinical *** cardiac tissues,resident macrophages fulfill critical functions in maintaining a stable cardiac state and have strong regenerative capacity and organ ***,the molecular mechanisms of macro-phages in HLHS remained ***:Single-nucleus RNA sequencing(snRNA-seq)data of HLHS and healthy control(donors)samples obtained from the Gene Expression Omnibus(GEO)database were normalized and clustered using the Seurat ***“FindMarkers”function was used to screen differentially expressed genes(DEGs)between the HLHS and donor groups and to analyze the functional enrichment of the set of genes of ***,cell-cell communication,pseudotime,and single-cell regulatory network inference and cluster-ing(SCENIC)analyses were used to study the mechanisms of macrophages in ***:Based on the snRNA-seq data of HLHS and donors,we identified a total of 9 cell clusters,among which the proportion of macrophages was significantly less in the HLHS group than in the control *** of macrophage subpopulations(Macrophages 1,2,and 3)showed that Macrophages 1 was mainly involved in nervous system development,angiogenesis,and apoptotic *** addition,analysis of communication between Macro-phages 1 and cardiomyocytes revealed that ligand-acceptor pairs such as GAS6/AXL,IL6,IGF1,THY1,and L1CAM were present only in the donor ***,pesudotime and SCENIC analyses demonstrated that FOXO3 and ELF2 played a critical role for Macrophages 1 to maintain cardiac function in patients with ***:Our study improved the current understanding of the molecular mechanisms of macrophage devel-opment in HLHS,showing that manipulating the regulatory role of macrophages in the heart can be a novel treat-ment for HLHS.

关键词： Hypoplastic left heart syndrome single-nucleus RNA sequencing macrophage cellular subpopulation transcription factor

Global Tangentially Analytical Solutions of the 3D Axially Symmetric Prandtl Equations

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Chinese Annals of Mathematics,Series B 2024年第4期45卷 573-596页

作者： Xinghong PAN Chaojiang xu School of Mathematics and Key Laboratory of MIIT Nanjing University of Aeronautics and Astronautics Laboratoire de Mathématiques Rapha?l Salem UMR 6085 CNRSUniversité de Rouen Normandie

In this paper,the authors will prove the global existence of solutions to the three dimensional axially symmetric Prandtl boundary layer equations with small initial data,which lies in H1Sobolev space with respect to the normal variable and is analytical with respect to the tangential *** main novelty of this paper relies on careful constructions of a tangentially weighted analytic energy functional and a specially designed good unknown for the reformulated *** result extends that of Paicu-Zhang in[Paicu,*** Zhang,P.,Global existence and the decay of solutions to the Prandtl system with small analytic data,***.,241（1）,2021,403–446].from the two dimensional case to the three dimensional axially symmetric case,but the method used here is a direct energy estimates rather than Fourier analysis techniques applied there.

关键词： Axially symmetric Global existence Prandtl equations Tangentially analytical solutions

The Essential 2-rank for Classical Groups

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2169-2186页

作者： Jian Bei AN Yong xu Department of Mathematics University of AucklandAucklandNew Zealand School of Mathematics and Statistics He’nan University of Science and TechnologyLuoyang 471023P.R.China

Let G be a symplectic or orthogonal group defined over a finite field with odd characteristic and let D≤G be a Sylow *** this paper,we classify the essential 2-subgroups and determine the essential 2-rank of the Frobenius category FD(G).Together with the results of An–Dietrich and Cao–An–Zeng,this completes the work of essential subgroups and essential ranks of classical groups.

关键词： Frobenius category conjugation families essential 2-rank symplectic groups orthogonal groups