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Electrically driven motion, destruction, and chirality change of polar vortices in oxide superlattices

Science China(Physics,Mechanics & Astronomy) 2022年第3期65卷 77-84页

作者： Pan Chen Congbing Tan Zhexin Jiang peng Gao Yuanwei Sun lifen {2. Xiaomei li Ruixue Zhu Lei liao Xu Hou Ke Qu {2. li Xiaomin li Zhi Xu Kaihui liu Wenlong {2. Jinbin {2. Xiaoping Ouyang Xiangli Zhong Jie {2. Xuedong Bai beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China International Center for Quantum Materials Electron Microscopy LaboratorySchool of PhysicsPeking UniversityBeijing 100871China Hunan Provincial Key Laboratory of Intelligent Sensors and Advanced Sensor Materials School of Physics and ElectronicsHunan University of Science and TechnologyXiangtan 411201China Department of Engineering Mechanics Zhejiang UniversityHangzhou 310027China Collaborative Innovation Center of Quantum Matter Beijing 100871China school of Physical sciences University of Chinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China State Key Laboratory for Artificial Microstructure&Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871China school of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Zhejiang UniversityHangzhou 310027China

Topological polar vortices, which are electric analogs of magnetic objects, present great potential in applications of future nanoelectronics because of their nanometer size, anomalous dielectric response, and chirality. To enable the functionalities, it is prerequisite to manipulate the polar states and chirality by using external stimuli. Here, we probe the evolutions of polar state and chirality evolutions of topological polar vortices in Pb TiO;/Sr TiO;superlattices under an electric field by using atomically resolved in situ scanning transmission electron microscopy and phase-field simulations. We find that, under electric field, the chiral vortex cores can be moved laterally to form close-pair structures, transform into a/c domain stripes, and finally become a nonchiral c-domain. Such transition is reversible and spontaneous after bias removal. Interestingly, during switching and backswitching events, the vortex rotation can be changed, offering a potential strategy to manipulate vortex chirality. The revealed dynamic behavior of individual polar vortices at the atomic scale provides fundamentals for future device applications.

关键词： chirality polar vortex ferroelectrics in situ transmission electron microscopy phase-field simulations

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中国广西、云南、贵州及东盟十国河流、湖库面域矢量及其覆盖率数据集

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中国科学数据（中英文网络版） 2024年第2期9卷 3-16页

作者：彭崇泰邱玉宝赵宁贾国强钟万洋王昭程桂林电子科技大学信息与通信学院广西桂林541004 可持续发展大数据国际研究中心北京100094 中国科学院空天信息创新研究院中国科学院数字地球重点实验室北京100094 中国–东盟地球大数据区域创新中心南宁530022

径流是水循环中的重要过程,流域中河流的分布信息对该区域的水资源、生态、环境及其社会经济活动具有重要意义。我国广西、云南、贵州和东盟十国属于多云雨、山地特点突出的区域,对比已有的河流面域数据产品,发现对该区域的河流信息表... 详细信息

径流是水循环中的重要过程,流域中河流的分布信息对该区域的水资源、生态、环境及其社会经济活动具有重要意义。我国广西、云南、贵州和东盟十国属于多云雨、山地特点突出的区域,对比已有的河流面域数据产品,发现对该区域的河流信息表征不足。为获得更为精确的河流分布数据,满足水资源及生态环境评估,本文采用欧亚大陆河流矢量数据(2.10)及欧空局(ESA)全球土地分类数据(2.2.)陆表水体产品,通过融合形成综合河流矢量数据,再采用膨胀和收缩缓冲分析方法,解决河流不连续问题,并制作了中国广西、云南、贵州及东盟十国河流面域矢量数据。通过对ESA土地分类数据的进一步处理,获得了同区域的湖泊面域矢量数据。最终,本文计算了河流和湖泊的覆盖率,并生成1 km格网的河流和湖库覆盖率数据集。与Hydro RIVERS数据集,以及4种水体遥感数据集(Global Surface water,Esri Land Cover,Dynamic World V1,GRWL)的对比结果显示,本数据集在研究区对河流水系的表征能力更强,比原始输入数据集具有更丰富的细节,表现为:本数据集填补了欧亚大陆河流矢量数据(2.10)中缺少的山区支流部分,解决了河流不连续、缺失等问题。本数据集为我国广西、云南、贵州及东盟十国的水体提取提供基础的先验数据,在洪水预报、水资源管理等方面具有重要价值,可服务于生态环境、交通运输、农业灌溉、能源等社会经济活动。

关键词：中国广西、云南、贵州东盟十国河流水系面域矢量数据集覆盖率

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Effects of higher-order aberrations on contrast sensitivity in normal eyes of a large myopic population

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International Journal of Ophthalmology(English edition) 2017年第9期10卷 1407-1411页

作者： peng-Fei Zhao Shi-Ming li Jing Lu Hong-Min Song Jing Zhang Yue-Hua Zhou {2.-li {2. Ophthalmic Center Beijing Tongren Hospital Capital Medical University Beijing Ophthalmology and Visual Sciences Key Lab Department of Ophthalmology Affiliated Hospital of Hebei Medical University College of Applied Arts and Science Beijing Union University

AIM：To study the relation between higher-order aberrations（HOAs）and contrast sensitivity（CS）in normal eyes among a population of laser in situ keratomileusis（LASIK）***：In 662. eyes of 3315 LASIK candidates,CS were measured under dark environment at the spatial frequencies of 1.5,3,6,12.and 18 cycles per degree（c/d）,respectively,using an Optec 6500 visual function ***,ocular HOAs were measured for a 6.0 mm pupil with a Hartmann-Shack wavefront ***：In the study,the subjects with an average spherical equivalent of-4.86±2.07 D were *** decreased from the third to the sixth order aberrations with predominant aberrations of third-order coma,trefoil and fourth-order spherical *** low and moderate spatial frequencies,CS was negatively correlated with the third-order coma and trefoil aberrations,and decreased with increasing Z31,but increased with increasing Z3-3and *** high spatial frequencies,CS decreased with increasing Z3-3and increased with increasing ***：At a large pupil size of 6.0 mm,the thirdorder aberrations,but not the total aberrations,are the main factors affecting *** coma is negatively correlated with CS.

关键词： myopia contrast sensitivity higher-orderaberrations coma spherical aberration

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Operando surface science methodology reveals surface effect in charge storage electrodes

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National Science Review 2021年第3期8卷 70-77页

作者： Chao wang Yanxiao ning Haibo Huang Shiwen {2. Chuanhai Xiao Qi Chen {2. {2. Shuainan Guo Yifan {2. Conghui {2.u Zhong-Shuai Wu Xianfeng {2. {2.wei Chen Chao Gao Chuan Wu Qiang Fu State Key Laboratory of Catalysis iChEMDalian Institute of Chemical PhysicsChinese Academy of Sciences university of Chinese Academy of sciences Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University beijing Key Laboratory of Environmental Science and Engineering School of Materials Science &Engineering Beijing Institute of Technology

Surface and interface play critical roles in energy storage devices,calling for operando characterization techniques to probe the electrified surfaces/*** this work,surface science methodology,including electron spectroscopy and scanning probe microscopy,has been successfully applied to visualize electrochemical processes at operating electrode surfaces in an Al/graphite model *** of anions together with cations is directly observed in the surface region of a graphite electrode with tens of nanometers thickness,the concentration of which is one order higher than that in *** intercalation pseudocapacitance mechanism and a double specific capacity in the electrode surface region are expected based on the super-dense intercalants and anion/cation co-intercalation,which are in sharp contrast to the battery-like mechanism in the electrode *** distinct electrochemical mechanism at the electrode surface is verified by performance tests of real battery devices,showing that a surface-dominant,nanometer-thick graphite cathode outperforms a bulk-dominant,micrometer-thick graphite *** findings highlight the important surface effect of working electrodes in charge storage systems.

关键词： surface science methodology aluminum ion battery operando characterization surface effect

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Dynamic Characteristic Analysis of HIV Mother to Child Transmission in China

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Biomedical and Environmental sciences 2010年第5期23卷 402-408页

作者： JUN-JIE wang KATHLEEN HEATHER REILLY HUA HAN ZHI-HANG peng {2. wang National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijing 100050China Tulane university Health sciences Center School of Public Health and Tropical MedicineNew OrleansLAUSA National ASIC Design Engineering Center Institute of AutomationChinese Academy of SciencesBeijing 100190China Department of Epidemiology and Biostatistics Nanjing Medical UniversityNanjing 210029China

Objective to explore dynamic characteristics of the HIV mother to child transmission （MTCT） epidemic in *** A deterministic dynamic transmission model was used to determine the effect of key parameters on the likely long-term trends of the HIV MTCT epidemic in *** 7.0 was used to develop the *** The number of the susceptibles （S）,the transmission rate （β）,and the screening proportion （α） of HIV positive pregnant women have the greatest impact on the HIV MTCT epidemic in *** growth of the MTCT epidemic in China could not be controlled only by decreasing the MTCT transmission *** prevalence of HIV positive women should be reduced and more pregnant women should be tested for *** Prevention of MTCT （PMTCT） should focus not only on the reduction of HIV transmission rates and incidences of HIV among women but also on the increase of HIV testing for pregnant *** most cost-effective PMTCT means for China should be investigated in future studies.

关键词： mother to child transmission dynamic model HIV China

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Atomic-scale structural and chemical evolution of li3V2.PO4)3 cathode cycled at high voltage window

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Nano Research 2019年第7期12卷 1675-1681页

作者： Shulin Chen Jian Zou Yuehui li {2. li Mei Wu Jinghuang lin Jingmin Zhang Jian Cao Jicai Feng Xiaobin Niu Jianming Bai Junlei Qi peng Gao liping {2. Hong li school of Materials and Energy State Key Laboratory of Electronic Thin Film and Integrated DevicesUniversity of Electronic Science and Technology oj ChinaChengdu 610054China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Electron Microscopy Laboratory School of PhysicsPeking UniversityBeijing 100871China National Synchrotron light Source II Brookhaven National LaboratoryUptonNew York 11973USA Collaborative Innovation Center of Quantum Matter Beijing 100871China International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Institute of Physics Chinese Academy of SciencesBeijing 100190China

Here,by using atomically resolved scanning transmission electron microscopy and electron energy loss spectroscopy,we investigate the structural and chemical evolution of li3V2.PO4)3 (LVP) upon the high-voltage window (3.0-4.8 V).We find that the valence of vanadium gradually increases towards the core corresponding to the formation of electrochemically inactive li3-xV2.PO4)3 (L3-xVP) *** li-deficient phases exhibit structure distortion with superstructure stripes,likely caused by the migration of the vanadium,which can slow down the lithium ion diffusion or even block the diffusion *** kinetic limitations lead to the formation of li-deficient phase along with capacity ***,the LVP continuously losses of electrochemical activity and li-deficient phases gradually grow from the particle core towards the surface during *** 500 cycles,the thickness of active LVP layer decreases to be - 5-2. ***,the micromorphology and chemical composition of solid electrolyte interphase (SEI) have been investigated,indicating the thick SEI film also contributes to the capacity *** present work reveals the structural and chemical evolution in the cycled electrode materials at an atomic scale,which is essential to understand the voltage fading and capacity decaying of LVP cathode.

关键词： lithium-ion batteries li-deficient lithium vanadium phosphate capacity fading solid electrolyte interphase scanning transmission electron microscopy electron energy loss spectroscopy

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Retinal vessels caliber changes after strabismus surgery：results of 6mo follow-up

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International Journal of Ophthalmology(English edition) 2016年第9期9卷 1325-1328页

作者： Ji-peng li Jing Fu Jin-Qiong Zhou Xiao-Zhen {2. Wen-Ying {2. ning-Pu liu beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical University beijing Ophthalmology &Visual sciences Key Lab Beijing 100005 China

AIM：To evaluate the effect of strabismus surgery on retinal vessels calibers with digital color fundus ***：Two hundred consecutive strabismus patients underwent surgery,and 118 patients（female/male,55/63） who finished 6-month follow-up were finally included in this *** disc-centered digital color fundus photographs of both eyes of all patients were taken prior to surgery and 6mo post *** retinal vascular caliber of 116 operated eyes were measured using the computer program *** operated eyes were divided into 3 groups according to the surgical methods,recession of one muscle,one muscle recession and one muscle folding,one muscle resection and one muscle *** effect of number of altered muscles on retinal vessels was analyzed using statistic software SPSS ***：The mean age was 12.4±*** central retinal artery equivalent（CRAE） of all patients was 12..31 ±2..02.μm preoperatively,and 12..87 ±15.93 μm six months after *** central retinal vein equivalent（CRVE） was 171.11 ±31.73 μm preoperatively and175.02.2..00 μm *** was no significant difference of averaged CRAE（P=0.2.） or CRVE（P=0.19）before and after *** arteriole to venule ratio（AVR） was 0.71 ±0.07 before surgery and 0.70±0.07 after *** of preoperative and postoperative retinal vessels calibers among different surgical groups did not show significant ***,there was no advantage of rectus muscle folding to muscle ***：Up to 6mo after strabismus surgery,the retinal vascular calibers were not *** more than two muscles in one surgery are safe for retinal perfusion.

关键词： strabismus retinal vascular caliber image processing computer-assisted

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基于环剪试验的蠕变型滑坡滑带力学性质——以甘肃舟曲地区锁儿头滑坡为例

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地球科学与环境学报 2024年第5期46卷 677-688页

作者：路昌明王祚鹏吴靓权烨孜宁瑞浩甘良橙中国地质大学(北京)工程技术学院北京100083 青海省地质环境监测总站青海西宁810008

蠕变型滑坡的变形与滑带力学性质关联十分紧密,研究不同含水率和不同砾石含量下滑带力学性质变化规律,对理解蠕变型滑坡的变形机制具有重要意义。以甘肃舟曲地区锁儿头滑坡滑带岩土体为研究对象,通过环剪试验探究滑带在不同含水率(15%、... 详细信息

蠕变型滑坡的变形与滑带力学性质关联十分紧密,研究不同含水率和不同砾石含量下滑带力学性质变化规律,对理解蠕变型滑坡的变形机制具有重要意义。以甘肃舟曲地区锁儿头滑坡滑带岩土体为研究对象,通过环剪试验探究滑带在不同含水率(15%、19%和2.%)、不同砾石含量(0%、5%和15%)和不同剪切速率(0.5、3.0和30.0 mm·min^(-1))下的力学性质变化规律。结果表明:①在长距离剪切下,滑带抗剪强度随含水率的增加而减小,而滑带达到峰值强度所需位移随含水率的增加而增加,同时滑带的残余黏聚力随含水率的升高而显著降低;②滑带抗剪强度随砾石含量的增加而增加;③随着剪切速率的增加,滑带抗剪强度逐渐减小,并且内摩擦角也呈现明显下降趋势。结合区域背景,甘肃舟曲地区锁儿头滑坡的蠕变速率与季节性降雨及断裂活动有关。

关键词：滑坡滑带环剪试验含水率砾石含量剪切速率残余强度甘肃

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Transcriptomic analyses reveal new genes and networks response to H5N1 influenza viruses in duck(Anas platyrhynchos)

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Journal of Integrative Agriculture 2019年第7期18卷 1460-1472页

作者： HUANG Yin-hua FENG Hua-peng HUANG li-ren YI Kang RONG En-guang CHEN Xiao-yun li Jian-wen wang Zeng ZHU peng-yang liU Xiao-juan wang Xiao-xue HU Jia-xiang liU Xin CHEN Hua-lan wang Jun li ning State Key Laboratory for Agrobiotechnology China Agricultural UniversityBeijing 100193P.R. China State Key Laboratory of Veterinary Biotechnology Harbin Veterinary Research InstituteChinese Academy of Agricultural SciencesHarbin 150069P.R.China BGI-Shenzhen Shenzhen 518083P.R.China China Veterinary Culture Collection Center China Institute of Veterinary Drug ControlBeijing 100081P.R.China

H5N1 influenza represents one of the great challenges to public *** H5N1 viruses(i.e.,A/goose/Hubei/65/05,GS/65) are weakly pathogenic,while the others(i.e.,A/duck/Hubei/49/05,DK/49) are highly pathogenic to their natural ***,we performed brain and spleen transcriptomic analyses of control ducks and ones infected by the DK/49 or the GS/65 H5N1 *** demonstrated that,compared to the GS/65 virus,the DK/49 virus infection changed more numerous immune genes’ expression and caused continuous increasing of immune pathways(i.e.,RIG-I and MDA5) in *** found that both H5N1 virus strains might escape or subvert host immune response through affecting alternative translation of immune genes,while the DK/49 virus seemed to induce alternative translation of more immune genes than the GS/65 *** also identified five co-expressional modules associated with H5N1 virus replication through the weight correlation network analysis(WGCNA).Moreover,we first demonstrated that the duck BCL2.L15 and DCSTAMP in one of these five modules inhibited both the highly pathogenic and weakly pathogenic H5N1 virus replication *** analyses,in combination with our comprehensive transcriptomic data,provided global view of the molecular architecture for the interaction between host and H5N1 viruses.

关键词： duck innate immune genes H5N1 influenza viruses transcriptomes

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Traffic Clustering Algorithm of Urban Data Brain Based on a Hybrid-Augmented Architecture of Quantum Annealing and Brain-Inspired Cognitive Computing

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清华大学学报：自然科学版（英文版） 2020年第6期25卷 813-825页

作者： ning wang Gege Guo Baonan wang Chao wang Key laboratory of Specialty Fiber Optics and Optical Access Networks Joint International Research Laboratory of Specialty Fiber Optics and Advanced CommunicationShanghai Institute for Advanced Communication and Data ScienceShanghai UniversityShanghai 200444China State Key Laboratory of Cryptology.beijing 100878 China Center for Quantum Computing Peng Cheng LaboratoryShenzhen 518000China

In recent years,the urbanization process has brought modernity while also causing key issues,such as traffic congestion and parking ***,cities need a more intelligent"brain"to form more intelligent and efficient transportation *** present,as a type of machine lear{2.,the traditional clustering algorithm still has limitations.K-means algorithm is widely used to solve traffic clustering problems,but it has limitations,such as sensitivity to initial points and poor ***,based on the hybrid architecture of Quantum Annealing(QA)and brain-inspired cognitive computing,this study proposes QA and Brain-Inspired Clustering Algorithm(QABICA)to solve the problem of urban taxi-stand *** on the traffic trajectory data of Xi’an and Chengdu provided by Didi Chuxing,the clustering results of our algorithm and K-means algorithm are *** find that the average taxi-stand location bias of the final result based on QABICA is smaller than that based on K-means,and the bias of our algorithm can effectively reduce the tradition K-means bias by approximately 42.,up to approximately 83%,with higher *** algorithm is able to jump out of the local suboptimal solutions and approach the global optimum,and brain-inspired cognitive computing provides search feedback and ***,we will further consider applying our algorithm to analyze urban traffic flow,and solve traffic congestion and other key problems in intelligent transportation.

关键词： cluster analysis intelligent transportation quantum annealing and brain-inspired clustering algorithm K-means

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