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Effective spin dephasing mechanism in confined two-dimensional topological insulators

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Science China(Physics,Mechanics & Astronomy) 2016年第7期59卷 70-75页

作者： junjie Qi HaiWen Liu Hua Jiang XinCheng Xie Institute of Physics Chinese Academy of Sciences Beijing 100190 China Center for Advanced Quantum Studies Department of Physics Beijing Normal University Beijing 100875 China College of Physics optoelectronics and Energy Soochow University Suzhou 215006 China International Center for Quantum Materials and School of Physics Peking University Beijing 100871 China Collaborative Innovation Center of Quantum Matter Beijing 100871 China

A Kramers pair of helical edge states in quantum spin Hall effect （QSHE） is robust against normal dephasing but not robust to spin dephasing. In our work, we provide an effective spin dephasing mechanism in the puddles of two-dimensional （2D） QSHE, which is simulated as quantum dots modeled by 2D massive Dirac Hamiltouian. We demonstrate that the spin dephasing effect can originate from the combination of the Rashba spin-orbit coupling and electron-phonon interaction, which gives rise to inelastic backscattering in edge states within the topological insulator quantum dots, although the time-reversal symmetry is preserved throughout. Finally, we discuss the tunneling between extended helical edge states and local edge states in the QSH quantum dots, which leads to backscattering in the extended edge states. These results can explain the more robust edge transport in InAs/GaSb QSH systems.

关键词： quantum spin Hall effect bound helical states spin dephasing Rashba spin-orbit coupling electron-phonon interaction

Evolution and impacts of the United States’Arctic strategy and China’s responses

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Advances in Polar Science 2023年第2期34卷 144-152页

作者： LIAO junjie PAN Min School of Political Science and International Relations Tongji UniversityShanghai 200092China

On 7 October,2022,the Biden administration released an updated version of the National Strategy for the Arctic Region based on new developments in the Arctic region and global *** strategy emphasizes traditional security issues in the Arctic,attaches great importance to climate governance in the region,and advocates for restoring American leadership through international *** view of the strong influence of the United States(U.S.)in the Arctic region,the changes of the *** strategy will inevitably have an impact on China’s scientific researchrights,economic interests,and governance rights in the Arctic *** respond to the new situation brought about by the changes in the *** strategy,China should take the initiative to maintain positive relationships with all Arctic countries,and continue its active participation in Arctic affairs.

关键词： the United States’Arctic strategy Arctic security Arctic governance

Effects of Rare Earth Pr/Ce on Tribological Behavior of ADC12 Alloy

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Journal of Wuhan University of Technology(Materials Science) 2021年第1期36卷 136-142页

作者： XU Lixiao YAN Hong LIU Wei XIONG junjie School of Mechanical and Electrical Engineering Nanchang UniversityNanchang 330031China Key Laboratory of Light Alloy Preparation and Processing Nanchang 330031China

The microstructure and microhardness of ADC12 alloy that was mixed with 0,0.3,0.6,and 0.9 wt.% rare earth praseodymium/cerium (Pr/Ce) were *** addition of Pr/Ce improved the microhardness of the *** ADC12+0.6 wt% Pr/Ce alloy displayed the smallest grain size and maximal *** tribological behavior of the alloys was tested by the pin-on-disc dry sliding friction pair with a sliding velocity of 0.21 m/s under various loads (20,40,60,80 N).The wear morphology was observed by a scanning electron microscope (SEM) and the wear mechanism was *** result indicated that the wear resistance of ADC12+0.6 wt% Pr/Ce alloy was the most *** wear rate relative to the matrix is reduced by 67.5% under a load of 20 *** wear mechanism is adhesive wear.

关键词： Pr/Ce ADC12 microstructure microhardness wear mechanism

EDITORIAL SPECIAL ISSUE ON SERVICE SYSTEMS AND SERVICE MANAGEMENT

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Journal of Systems Science and Systems Engineering 2018年第4期27卷 394-398页

作者： Chunguang Bai junjie Wu Yongbo Xiao School of Management and Economics University of Electronic Science and Technology of China Chengdu 610054 China School of Economics and Management Beihang University Beijing 100191 China School of Economics and Management Tsinghua University Beijing 100084 China

Service system or service management is a value coproduction configuration of person, facilities, tools, organizational network, technology, internal and external service systems connected via value propositions, and shared information that satisfy the needs or aspirations of customers. The mankind has entered the era of globalization in 21st century, the interdependence of things in service system becomes closer and the interaction is more complex. The service system is a complex system that is affected by the demand forecasting, customer relationship, public relations, customer behavior, satisfaction, and retention, service cost, profitability of service investment, risk, and so on.

关键词： Service system service management complex system

Preparation and characterization of carbon pillared clay material

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Science China(Technological Sciences) 2009年第1期52卷 210-214页

作者： ZHANG ZengZhi YANG ChunWei NIU junjie Institute of Ecological and Functional Materials China University of Mining and TechnologyBeijing 100083China

Carbon pillared clay material was prepared from montmorillonite modified by C19H42BrN and C10H16ClN. SEM, FT-IR, XRD, N2 adsorption-desorption, thermal-gravimetric analysis and differential scanning calorimetry were employed to characterize the pore structure and test the effect of surfactant. The results show that organic modifier combines with montmorillonite particles by covalent bond and ion embedded. The microstructure of carbon pillared material looks like needle slice. The most probable pore size distribution is about 1.7 nm. The clay material slice mainly consists of two-dimensional aperture supported by a carbonization pillar. The high-temperature stability of carbon pillared clay is im- proved.

关键词： carbon pillared modified montmorillonite two-dimensional aperture surfactant

Convex optimization of virtual storage system scheduling in market environment

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Journal of Modern Power Systems and Clean Energy 2019年第6期7卷 1735-1739页

作者： Peng HOU junjie HU Guangya YANG Center of Electrical Engineering Technical University of DenmarkElektrovejBuilding 325LyngbyDenmark State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China

Due to the popularization of distributed energy resources(DERs),the aggregated prosumer effect excels a general energy storage system *** energy storage system(VESS)concept is proposed hereby that mimics an actual storage unit and incorporates the same charging(consumer)and discharging(producer)*** is possible to provide ancillary services via VESS by exploiting the flexibility and thus much research has been proposed on the optimization of the VESS *** general,the charging and discharging efficiencies of VESS are different and there can be only one status at a time *** achieve the optimal schedule while considering the constraints above,binary terms should be introduced into the optimization problem which end up with a nonconvex *** this paper,a complimentary mathematical proof is given for the convexification of this mixed-integer linear programming(MILP)problem so that the linear programming(LP)method can be applied instead if the objective function is *** proposed proof is validated through a case study and the simulation results show the effectiveness of the proposed method.

关键词： Virtual energy storage system(VESS) Convexification Mixed linear programming(MILP) Complimentary mathematical proof

When the Exotic Met the Erotic： The Representation of the Foreign in Ruyijun zhuan and ＂Jinhailing zongyu wangshen＂

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2014年第2期8卷 277-301页

作者： junjie Luo Department of East Asian Studies Dickinson College Carlisle PA 17013 USA

Erotic fiction produced during the 16th and the early 17th centuries used different strategies to create settings for subversive sexual desires. This article examines one of these strategies： Authors of Ming erotic stories often associated the sexual expressions that challenged the existing social order with portrayals of the foreign. This article demonstrates that historical accounts and literary traditions informed the representations of the foreign in Ming erotic stories produced during the mid- and late Ming period through the examination ofRuyijun zhuan and ＂Jinhailing zongyu wangshen.＂ I argue that both narratives exoticized the erotic in order to exclude unsettling elements of sexual desire from China. However, due to their different views of sexual desire, they depicted the foreign differently. This paper concludes that the different strategies for appropriating sexual desire into foreign settings may be related to the historical contexts within which the two works of fiction were created.

关键词： eroticism foreign "Jinhailing zongyu wangshen," Ruyo'un zhuan,Ming dynasty

人工智能在脊髓神经损伤与修复领域研究热点的可视化分析

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中国组织工程研究 2025年第4期29卷 761-770页

作者：杨彬陶广义杨顺许俊杰黄俊卿河南省中医院/河南中医药大学第二附属医院疼痛科河南省郑州市450000 河南中医药大学骨伤学院河南省郑州市450000

背景:近年来人工智能逐渐兴起,在多方面应用于脊髓神经损伤与修复领域,对临床治疗也有诸多积极影响。目的:研究人工智能在脊髓神经损伤与修复领域的诊断、治疗和康复中的应用进展,明确该领域的研究热点和不足,为今后研究工作提供建议。... 详细信息

背景:近年来人工智能逐渐兴起,在多方面应用于脊髓神经损伤与修复领域,对临床治疗也有诸多积极影响。目的:研究人工智能在脊髓神经损伤与修复领域的诊断、治疗和康复中的应用进展,明确该领域的研究热点和不足,为今后研究工作提供建议。方法:在Web of Science核心集数据库检索建库至2023年收录的人工智能在脊髓神经损伤与修复领域相关文献,使用CiteSpace 6.1.R6和VOSviewer 1.6.19软件对文献数据进行一般文献学分析、文献共被引、期刊共被引、期刊双图叠加及关键词聚类等可视化分析。结果与结论:①共筛选出1713篇文章,此领域年发文量呈波动上升趋势,其中美国占据主导地位,Kadone Hideki是发文量最多的作者,《ARCH PHYS MED REHAB》是被引用次数最多的期刊。②关键词共现和聚类分析显示,去除与检索词相近的关键词后,主要关键词被分为3个主要集群:外骨骼与运动康复(为最大核心热点)、机器学习和神经可塑性、机器人和康复训练。③关键词爆发分析显示,深度学习和人工智能在过去5年中已成为突发术语。④文献共被引和高被引文献分析结果显示,人工智能在脊髓神经损伤与修复领域热点集中于动力外骨骼(powered exoskeleton)、步态(gait)、神经电刺激(electrical nerve stimulation)、皮质内脑机接口(intracortical brain-computer interface,IBCI)、机器人(robot)、高分子生物材料(polymer biomaterials)及神经干细胞(neural stem cell)等内容。⑤人工智能在脊髓神经损伤与修复领域的研究近年来呈现上升趋势,该领域的关注点从外骨骼、电刺激等单一的治疗手段,逐渐向智能化、精准化和个性化等方向转变。⑥该领域存在一些局限性,例如数据缺失或不平衡的后果、数据准确性和可重复性低以及伦理问题(如隐私、研究透明度和临床可靠性等),未来的研究应该解决数据收集的问题,需要大样本、高质量的临床数据集来建立有效的人工智能模型;同时该领域的基因组学等机制研究十分薄弱,未来可利用类脑芯片等多种机器学习技术,运用基因编辑治疗及单细胞空间转录组等方法,进行再生相关基因上调和轴突生长结构蛋白产生等基础机制研究。

关键词：人工智能神经再生脊髓损伤机器外骨骼脑机接口神经电刺激脑皮质重组深度学习机器学习神经网络

Effect of Current Density on Microstructure and Corrosion Behavior of Plasma Electrolytic Oxidation Coated 6063 Aluminum Alloy

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Journal of Wuhan University of Technology(Materials Science) 2018年第6期33卷 1503-1510页

作者： ZHUANG junjie SONG Renguo School of Materials Science and Engineering Changzhou University Jiangsu Key Laboratory of Materials Surface Science and Technology Changzhou University Jiangsu Collaborative Innovation Center of Photovolatic Science and Engineering Changzhou University School of Materials Science and Engineering Jiangsu University of Science and Technology

Plasma electrolytic oxidation(PEO) coatings were fabricated on 6063 aluminum alloy in a cheap and convenient electrolyte. The effect of different current densities, i e, 5, 10, 15, and 20 A/dm2on the microstructure and corrosion behavior of coatings was comprehensively studied by scanning electron microscopy(SEM), stereoscopic microscopy, potentiodynamic polarization and electrochemical impedance spectroscopy(EIS), respectively. It is found that the pore density decreases and the pore size increases with increasing current density. The XRD results show that the coatings are only composed of α-Al2O3and γ-Al2O3. Potentiodynamic polarization test proves that the coating formed under 10 A/dm2possesses the best anticorrosion property. The long time EIS test shows that the coating under 10 A/dm2is able to protect the aluminum alloy substrate after long time of immersion in 0.59 M NaCl solution, which confirms the salt solution immersion test results in 2 M NaCl solution.

关键词： coating 6063 aluminum alloy plasma electrolytic oxidation (PEO) current density corrosion resistance