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Nano Research 2023年第12期16卷 13509-13515页

作者： Yang Song wen-han dong Kuan-Rong Hao Shixuan Du Lizhi Zhang Laboratory of Theoretical and Computational Nanoscience National Center for Nanoscience and TechnologyBeijing 100190China Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijing 100084China

Magnetic materials could realize the intriguing quantum anomalous Hall effect and metal-to-insulator transition when combined with band topology or electronic correlation,which have broad prospects in quantum information,spintronics,and ***,we propose the approach of designing novel two-dimensional(2D)magnetic states via d-orbital-based superatomic ***,we chose triangular zirconium dichloride disks as superatoms to construct the honeycomb superatomic *** first-principles calculations,we identified a series of 2D magnetic states with varying sizes of *** found the non-uniform stoichiometries and geometric effect of superatomic lattice give rise to spin-polarized charges arranged in different magnetic configurations,containing ferromagnetic coloring triangles,antiferromagnetic honeycomb,and ferromagnetic kagome ***,these magnetic states are endowed with nontrivial band topology or strong correlation,forming an ideal Chern insulator or antiferromagnetic Dirac Mott *** work not only reveals the potential of d-orbital-based superatoms for generating unusual magnetic configurations,but also supplies a new avenue for material engineering at the nanoscale.

关键词： topological state Chern insulator Dirac Mott insulator zirconium dichloride superatomic lattice kagome lattice

Superconductivity and topological aspects of two-dimensional transition-metal monohalides

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npj Computational Materials 2022年第1期8卷 1763-1770页

作者： wen-han dong Yu-Yang Zhang Yan-Fang Zhang Jia-Tao Sun Feng Liu Shixuan Du Beijing National Center for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing100049China CAS Center for Excellence in Topological Quantum Computation Beijing100190China School of Integrated Circuits and Electronics MIIT Key Laboratory for Low-Dimensional Quantum Structure and DevicesBeijing Institute of TechnologyBeijing100081China Department of Materials Science and Engineering University of UtahSalt Lake CityUtah84112USA Songshan Lake Materials Laboratory Dongguan523808China

Two-dimensional(2D)superconducting states have attracted much recent interest,especially when they coexist with nontrivial band topology which affords a promising approach towards Majorana *** first-principles calculations,we predict van der Waals monolayered transition-metal monohalides MX(M=Zr,Mo;X=F,Cl)as a class of 2D superconductors with remarkable transition temperature(5.9–12.4 K).Anisotropic Migdal-Eliashberg theory reveals that ZrCl have a single superconducting gap∆~2.14 meV,while MoCl is a two-gap superconductor with∆~1.96 and 1.37 *** Z_(2)band topology of 2D MX is further demonstrated that MoF and MoCl are candidates for realizing topological ***,the Dirac phonons of ZrCl and MoCl contribute w-shape phononic edge states,which are potential for an edge-enhanced electron-phonon *** findings demonstrate that 2D MX offers an attractive platform for exploring the interplay between superconductivity,nontrivial electronic and phononic topology.

关键词： topological transition nontrivial

Manipulation of Dirac Fermions in Nanochain-Structured Graphene

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Chinese Physics Letters 2021年第9期38卷 74-79页

作者： wen-han dong De-Liang Bao Jia-Tao Sun Feng Liu Shixuan Du Institute of Physics and University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100190China School of Information and Electronics MIIT Key Laboratory for Low-Dimensional Quantum Structure and DevicesBeijing Institute of TechnologyBeijing 100081China Department of Materials Science and Engineering University of UtahSalt Lake CityUtah 84112USA CAS Center for Excellence in Topological Quantum Computation Beijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China

Graphene has afforded an ideal 2D platform for investigating a rich and fascinating behavior of Dirac ***,we develop a theoretical mechanism for manipulating the Dirac fermions in graphene,such as from type- Ⅰ to type-Ⅱ and type-Ⅲ,by a top-down nanopatterning *** demonstrate that by selective chemical adsorption to pattern the 2D graphene into coupled 1D armchair chains(ACs),the intrinsic isotropic upright Dirac cone becomes anisotropic and strongly *** on model analyses and first-principles calculations,we show that both the shape and tilt of Dirac cone can be tuned by the species of chemisorption,e.g.,halogen vs hydrogen,which modifies the strength of inter-AC ***,the topological edge states and transport properties of the engineered Dirac fermions are *** work sheds lights on understanding the Dirac fermions in a nanopatterned graphene platform,and provides guidance for designing nanostructures with novel functionality.

关键词： Dirac Fermi topological

Nonvolatile electrical control of spin polarization in the 2D bipolar magnetic semiconductor VSeF

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npj Computational Materials 2023年第1期9卷 1838-1847页

作者： Yuhui Li Jun Deng Yan-Fang Zhang Xin Jin wen-han dong Jia-Tao Sun Jinbo Pan Shixuan Du Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of Sciences100190 BeijingChina University of Chinese Academy of Sciences Chinese Academy of Sciences100190 BeijingChina School of Integrated Circuits and Electronics MIIT Key Laboratory for Low-Dimensional Quantum Structure and DevicesBeijing Institute of Technology100081 BeijingChina Songshan Lake Materials Laboratory 523808 DongguanChina CAS Center for Excellence in Topological Quantum Computation 100190 BeijingChina

Nonvolatile electrical control of spin polarization in two-dimensional(2D)magnetic semiconductors is greatly appealing toward future low-dissipation spintronic ***,we report a 2D material VSeF,which is an intrinsic bipolar magnetic semiconductor(BMS)featured with opposite spin-polarized valence and conduction band *** then propose a general nonvolatile strategy to manipulate both spin-polarized orientations in BMS materials by introducing a ferroelectric gate with proper band *** spin-up/spin-down polarization of VSeF is successfully controlled by the electric dipole of ferroelectric bilayer Al_(2)Se_(3),verifying the feasibility of the design *** interfacial doping effect from ferroelectric gate also plays a role in enhancing the Curie temperature of the VSeF *** types of spin field effect transistors,namely multiferroic memory and spin filter,are further achieved in VSeF/Al_(2)Se_(3) and VSeF/Al_(2)Se_(3)/Al_(2)Se_(3) multiferroic heterostructures,*** work will stimulate the application of 2D BMS materials in future spintronic nanodevices.

关键词： ferroelectric volatile magnetic

Ontogenetic trait variation and metacommunity effects influence species relative abundances during tree community assembly

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Plant Diversity 2022年第4期44卷 360-368页

作者： Yun-Yun He Kwansupa Srisombut Ding-Liang Xing Nanthan G.Swenson Mengesha Asefa Min Cao Xiao-Yang Song han-dong wen Jie Yang CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla666303YunnanChina University of Chinese Academy of Sciences Beijing100049China School of Ecological and Environmental Sciences East China Normal UniversityShanghai200241China Department of Biological Sciences University of Notre DameNotre DameIN46556USA Center of Plant Ecology Core Botanical GardensChinese Academy of SciencesMengla666303YunnanChina

Predicting species abundance is one of the most fundamental pursuits of *** the information encoded in functional traits and metacommunities provides a new perspective to predict the abundance of species in *** applied a community assembly via trait selection model to predict quadrat-scale species abundances using functional trait variation on ontogenetic stages and metacommunity information for over 490 plant species in a subtropical forest and a lowland tropical forest in Yunnan,*** relative importance of trait-based selection,mass effects,and stochasticity in shaping local species abundances is evaluated using different null *** found both mass effects and trait selection contribute to local abundance *** selection was detectable at all studied spatial scales(0.04e1 ha),with its strength stronger at larger scales and in the subtropical *** contrast,the importance of stochasticity decreased with spatial scale.A significant mass effect of the metacommunity was observed at small spatial *** results indicate that tree community assembly is primarily driven by ontogenetic traits and metacommunity *** findings also demonstrate that including ontogenetic trait variation into predictive frameworks allows ecologists to infer ecological mechanisms operating in community assembly at the individual level.

关键词： Metacommunity Maximum entropy Ontogenetic trait variation Community assembly Trait-selected process

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Neural Regeneration Research 2023年第9期18卷 1968-1975页

作者： He-Mei Huang Gui-Sheng Chen Zhong-Yi Liu Qing-Lin Meng Jia-Hong Li han-wen dong Yu-Chen Chen Fei Zhao Xiao-Wu Tang Jin-Liang Gao Xi-Ming Chen Yue-Xin Cai Yi-Qing Zheng Department of Otolaryngology Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Institute of Hearing and Speech-Language Science Sun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Department of Otolaryngology Shenzhen-Shanwei Central HospitalSun Yat-sen Memorial HospitalSun Yat-sen UniversityShanweiGuangdong ProvinceChina Department of Radiology Guangdong Provincial Work Injury Rehabilitation HospitalGuangzhouGuangdong ProvinceChina Acoustics Lab of School of Physics and Optoelectronics and State Key Laboratory of Subtropical Building Science South China University of TechnologyGuangzhouGuangdong ProvinceChina Department of Radiology Nanjing First HospitalNanjing Medical UniversityNanjingJiangsu ProvinceChina Department of Speech and Language Therapy and Hearing Science Cardiff Metropolitan UniversityCardiffUK Department of Otolaryngology Shenzhen Baoan Maternal and Child Health HospitalShenzhenGuangdong ProvinceChina

Patients with age-related hearing loss face hearing difficulties in daily *** causes of age-related hearing loss are complex and include changes in peripheral hearing,central processing,and cognitive-related ***,the factors by which aging relates to hearing loss via changes in audito ry processing ability are still *** this cross-sectional study,we evaluated 27 older adults(over 60 years old) with age-related hearing loss,21 older adults(over 60years old) with normal hearing,and 30 younger subjects(18-30 years old) with normal *** used the outcome of the uppe r-threshold test,including the time-compressed thres h old and the speech recognition threshold in noisy conditions,as a behavioral indicator of auditory processing *** also used electroencephalogra p hy to identify presbycusis-related abnormalities in the brain while the participants were in a spontaneous resting *** timecompressed threshold and speech recognition threshold data indicated significant diffe rences among the *** patients with age-related hearing loss,information masking(babble noise) had a greater effect than energy masking(speech-shaped noise) on processing *** terms of resting-state electroencephalography signals,we observed enhanced fro ntal lobe(Brodmann’s area,BA11) activation in the older adults with normal hearing compared with the younger participants with normal hearing,and greater activation in the parietal(BA7) and occipital(BA19) lobes in the individuals with age-related hearing loss compared with the younger *** functional connection analysis suggested that compared with younger people,the older adults with normal hearing exhibited enhanced connections among networks,including the default mode network,sensorimotor network,cingulo-opercular network,occipital network,and frontoparietal *** results suggest that both normal aging and the development of age-related hearing loss have a negative effect on

关键词： age-related hearing loss aging electroencephalography fast-speech comprehension functional brain network functional connectivity restingstate sLORETA source analysis speech reception threshold

亚热带山地森林木质藤本和共生树木枝条和叶片性状的分化

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Journal of Plant Ecology 2024年第1期17卷 17-32页

作者： Xiao-Long Bai Da Yang Jan Sher Yun-Bing Zhang Ke-Yan Zhang Qi Liu han-dong wen Jiao-Lin Zhang Martijn Slot CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunMengla 666303China University of Chinese Academy of Sciences Beijing 100049China Forest Ecology and Forest Management Group Wageningen University and Research Centre6700 AA WageningenThe Netherlands Yuanjiang Savanna Ecosystem Research Station Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesYuanjiang 653300China Smithsonian Tropical Research Institute Apartado 0843-03092BalboaAnconRepublic of Panama

因缺少性状的比较,我们对亚热带山地森林木质藤本和树木的与生态适应策略有关的功能性状变异格局仍知之甚少。本文通过研究中国西南亚热带山地森林中不同叶片习性的33种植物(7种落叶和4种常绿木质藤本、10种落叶和12种常绿树木)的13个... 详细信息

因缺少性状的比较,我们对亚热带山地森林木质藤本和树木的与生态适应策略有关的功能性状变异格局仍知之甚少。本文通过研究中国西南亚热带山地森林中不同叶片习性的33种植物(7种落叶和4种常绿木质藤本、10种落叶和12种常绿树木)的13个性状的分化来填补此空白。研究结果表明,木质藤本的枝条木质部导管直径、理论导水率、比叶面积、叶片氮和磷含量显著高于树木,但其叶片干物质含量和氮磷比显著低于同域分布的树木,表明木质藤本采取获取的生态策略,具有更高效的枝条导水系统和生产力更强的叶片。与树木相比,木质藤本的导管直径变异更大,同时具有一些大导管和很多小导管,说明木质藤本具有较大的导管二型性。生长型解释了性状总变异的48.7%,叶片习性仅解释了3.8%的总变异,生长型和叶片习性之间没有显著的交互作用。此外,枝叶性状仅在树木中存在显著相关,木质藤本中不存在,表明亚热带木质藤本枝条的水力功能与叶片的性状是解耦的。上述结果表明,亚热带山地木质藤本和树木的枝条和叶片功能性状存在显著差异。加强对亚热带山地生态系统中木质藤本和树木生态策略差异机制的认识还需要深入研究。

关键词：功能性状叶片习性叶片形态木质藤本亚热带山地森林木质部解剖

基于Internet的网络控制系统端到端时延分析

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计算机工程 2007年第22期33卷 158-160页

作者：邬春学韩文冬上海理工大学计算机工程学院上海200093

端到端时延是影响基于Internet网络控制系统(NCS)稳定性的一个重要因素。该文通过OPNET建模仿真,分析了系统的端到端时延特征、时延组成及时延瓶颈。讨论了不同的数据包大小对端到端时延的影响及其原因,把该时延用于一个NCS仿真实例,分... 详细信息

端到端时延是影响基于Internet网络控制系统(NCS)稳定性的一个重要因素。该文通过OPNET建模仿真,分析了系统的端到端时延特征、时延组成及时延瓶颈。讨论了不同的数据包大小对端到端时延的影响及其原因,把该时延用于一个NCS仿真实例,分析了其对系统稳定性的影响。在NCS的设计过程中,明确端到端时延特征有助于提高系统的稳定性。

关键词：网络控制系统端到端时延 OPNET 不确定性稳定性

AODV在移动自组网络控制系统中的应用研究

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计算机应用 2007年第10期27卷 2388-2390页

作者：邬春学韩文冬上海理工大学计算机与电气工程学院上海200093

在对AODV的路由建立及路由维护机制分析的基础上,结合移动自组网络控制系统(NCS)中数据传输的特点,对AODV的路由维护机制做了改进,即当链路中断时立刻由影响到的源节点发起路由建立,以减少网络延时。NS2仿真结果表明,当网络规模不大时,... 详细信息

在对AODV的路由建立及路由维护机制分析的基础上,结合移动自组网络控制系统(NCS)中数据传输的特点,对AODV的路由维护机制做了改进,即当链路中断时立刻由影响到的源节点发起路由建立,以减少网络延时。NS2仿真结果表明,当网络规模不大时,改进后的协议能有效减少移动自组NCS端到端平均延时,有助于提高系统的可靠性。

关键词： AdHoc按需距离矢量路由协议端到端延时移动自组网络控制系统 NS2仿真

Effect of betaine on sustained hypertension induced learning and memory injury in SHR rats

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中国药理学与毒理学杂志 2021年第9期35卷 649-649页

作者： CHEN Jiang-yan han wen-dong GAO Shan Shandong First Medical University Jinan 271000China

OBJECTIVE To observe the effects of betaine on learning memory in SHR rats through behavioral experiments,and then to investigate the mechanisms of betaine to improve the cognitive impairment caused by hyperten⁃*** 4-month-old male SHR rats were randomly divided into 4 groups,including betaine 10,30 and 100 mg·kg-1 groups and SHR group,and administered by gavage,10 mL·kg-1 once a day for 4 *** control group was WKY rats,and the same amount of saline was given by *** learning and memory behaviors of the rats were analyzed and evaluated through behavioral *** The results of Morris water maze showed that persistent hypertension decreased the time in the target quadrant and the number of platform crossing of the rats,and the intervention with different con⁃centrations of betaine increased the time in the target quadrant and the number of platform crossing of SHR in a dose-dependent ***,persistent hypertension increased the escape latency of rats,and betaine inhibited this *** results of new object recognition showed that the recognition index of SHR group decreased,and the recognition index of SHR rats increased with different concentrations of betaine intervention in a dose-dependent *** Y-maze results showed that persistent hypertension decreased the alternation in rats,and the alternation in SHR rats increased after the intervention with different concentrations of betaine,and in a dose-dependent ***⁃CLUSION Persistent hypertension can cause learning memory impairment in *** intervention has an ameliorative effect on the reduction of learning memory ability in rats caused by hypertension.

关键词： betaine hypertension learning and memory