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Nano Research 2018年第6期11卷 3031-3049页

作者： qiuyang li Tianquan lian Department of Chemistry Emory University 1515 Dickey Drive NE Atlanta GA 30322 USA

Solar-to-H2 conversion is attracting much research attention as a potential approach to meet global renewable energy demands. Although significant advances have been made using metal-tipped colloidal cadmium chalcogenide zero-dimensional （0D） quantum dots and one-dimensional （1D） nanorod heterostructures in solar-to-H2 conversion, their efficiency may be further enhanced using an emerging class of colloidal cadmium chalcogenide nanocrystals, namely two-dimensional （2D） nanoplatelets （NPLs）, because of their unique properties. In this review, we summarize the recent advances on exciton dissociation dynamics and light-driven H2 generation performance of colloidal nanoplatelet heterostructures. Following an introduction on the electronic structure of 2D NPLs, we discuss the dynamics of exciton dissociation by electron transfer to molecular acceptors. The exciton quenching dynamics of CdS NPL-Pt and CdSe NPL-Pt heterostructures are compared to highlight the effect of material properties on the relative contributions of the energy-transfer and electron- transfer pathways. Representative solar-to-H2 conversion performances of 2D NPL-metal heterostructures are discussed and compared with those of 1D nanorod-metal heterostructures. Finally, we discuss the challenges in further improving the solar-to-fuel conversion efficiencies of these systems.

关键词： colloidal nanoplatelets semiconductor-metal heterostructures exciton dissociation electron transfer hydrogen generation

A Novel Undulatory Propulsion Strategy for Underwater Robots

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Journal of Bionic Engineering 2021年第4期18卷 812-823页

作者： qiuyang li Jinhua Zhang Jun Hong Debin Hu Yuhan Yang Songzi Guo Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an710049China

Stingrays can undulate their wide pectoral fins to thrust themselves and swim freely *** researchers have used bionics to directly imitate their undulating mechanism and manufacture undulatory underwater *** on the limitations of the existing undulatory underwater robots,this paper proposes a novel undulatory propulsion strategy,which aims to use the stingray undulating mechanism more ***,the mathematical models of both traditional and novel structures are established to accurately describe their undulating ***,based on the dynamic mesh technology,the flow field vortex structure they generated is analyzed through fluid-structure interaction simulation,and the thrust force and lateral force generated by them are calculated,which verified that this novel propulsion strategy is indeed more ***,a prototype robot based on the improved propulsion strategy is *** with the existing stingray robots,the prototype has obvious advantages,thus verifying the accuracy of the simulation results.

关键词： bionic underwater robot stingray undulatory propulsion mechanism fluid-structure interaction

The most typical shape of oceanic mesoscale eddies from global satellite sea level observations

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Frontiers of Earth Science 2015年第2期9卷 202-208页

作者： Zifei WANG qiuyang li liang SUN Song li Yuanjian YANG Shanshan liU Key Laboratory of the Atmospheric Composition and Optical Radiation CAS School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography State Oceanic Administration HangZhou 310012 China Key Laboratory of Atmospheric Sciences and Satellite Remote Sensing of Anhui Province Anhui Institute of Meteorological Sciences Hefei 230031 China

In this research, we normalized the character- istics of ocean eddies by using satellite observation of the Sea Level Anomaly （SLA） data to determine the most typical shape of ocean eddies. This normalization is based on modified analytic functions with nonlinear optimal fitting. The most typical eddy is the Taylor vortex （~50%）, which exhibits a Gaussian-shaped exp（-r2） SLA and a vorticity distribution of （1-rZ）exp（-r2） as a function of the normalized radii r. The larger the amplitude of the eddy, the more likely the eddy is to be Gaussian-shaped. Furthermore, approximately 40% of ocean eddies are combinations of two Gaussian eddies with different parameters, but the composition of these types of eddies is more like a quadratic eddy than a Gaussian one. Only a small portion of oceanic eddies are pure quadratic eddies （〈 10%） with the same vorticity distribution as a Rankine vortex. We concluded that the Taylor vortex is a good approximation of the typical shape of ocean eddies.

关键词： sea level anomaly ocean eddies Taylorvortex typical shape

Spin-Wave Dynamics in an Artificial Kagome Spin Ice

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Chinese Physics Letters 2021年第4期38卷 117-121页

作者： qiuyang li Suqin Xiong lina Chen Kaiyuan Zhou Rongxin Xiang Haotian li Zhenyu Gao Ronghua liu Youwei Du China Electric Power Research Institute Beijing 100192China School of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Physics Nanjing UniversityNanjing 210093China

Artificial spin ice(ASI) structures have significant technological potential as reconfigurable metamaterials and magnetic storage *** investigate the field/frequency-dependent magnetic dynamics of a kagome ASI made of 25-nm-thick permalloy nanomagnet elements,combining magnetoresistance(MR) and microscale ferromagnetic resonance(FMR) *** FMR spectra show a broadband absorption spectrum from 0.2 GHz to 3 GHz at H below 0.3 kOe,where the magnetic configuration of the kagome ASI is in the multidomain state,because the external magnetic field is below the obtained coercive field Hc~0.3 kOe,based on both the low-field range MR loops and simulations,suggesting that the low-field magnetization dynamics of kagome ASI is dominated by a multimode resonance ***,the FMR spectra exhibit five distinctive resonance modes at the highfield quasi-uniform magnetization ***,our micromagnetic simulations provide additional spatial resolution of these resonance modes,identifying the presence of two high-frequency primary modes,localized in the horizontal and vertical bars of the ASI,respectively;three other low-frequency modes are mutually exclusive and separately pinned at the corners of the kagome ASI by an edge-induced dipolar *** results suggest that an ASI structural design can be adopted as an efficient approach for the development of low-power filters and magnonic devices.

关键词： alloy magnetization corners

The Lateral Eddy Viscosity Derived from the Decay of Oceanic Mesoscale Eddies

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Open Journal of Marine Science 2018年第1期8卷 152-172页

作者： qiuyang li liang Sun Chi Xu School of Earth and Space Sciences University of Science and Technology of China Hefei China State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China

The relationship of lateral eddy viscosity depending on length scale is estimated with the decay rate of mesoscale eddies identified from sea level anomaly of satellite observations. The eddy viscosity is expressed in terms of the mesoscale eddy parameters according to vortex dynamics. The census of mesoscale eddies shows, in general, that the eddy numbers obey the e-folding decay laws in terms of their amplitude, area and lifetime. The intrinsic values in the e-folding laws are used to estimate the lateral eddy viscosity. Dislike the previous theory that diffusivities are proportional to the length square, the eddy mixing rates (diffusivity and viscosity) from satellite mesoscale eddy datasets are proportional to rs to power of 1.8 (slightly less than 2), where rs is the radius of eddy with radius larger than the Batchelor scale. Additionally, the extrapolation of the eddy mixing to the molecule scale implies that the above power laws may hold until the value of rs is less than O (1 m). These mixing rates with the new parameterizations are suggested to use in numerical schemes. Finally, the climatological distributions of eddy viscosity are calculated.

关键词： Eddy Mixing Eddy Viscosity Mesoscale Eddy

Experiments and SPICE simulations of double MgO-based perpendicular magnetic tunnel junction

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Chinese Physics B 2021年第4期30卷 518-525页

作者： qiuyang li Penghe Zhang Haotian li lina Chen Kaiyuan Zhou Chunjie Yan liyuan li Yongbing Xu Weixin Zhang Bo liu Hao Meng Ronghua liu Youwei Du China Electric Power Research Institute Beijing 100192China School of Physics Nanjing UniversityNanjing 210093China School of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Electronics Science and Engineering Nanjing UniversityNanjing 210093China State Grid Tianjin Electric Power Company Tianjin 300384China Key Laboratory of Spintronics Materials Devices and Systems of Zhejiang ProvinceZhejiang 311300China

We investigate properties of perpendicular anisotropy magnetic tunnel junctions(pMTJs) with a stack structure MgO/CoFeB/Ta/CoFeB/MgO as the free layer(or recording layer),and obtain the necessary device parameters from the tunneling magnetoresistance(TMR) *** loops and current-driven magnetization switching *** on the experimental results and device parameters,we further estimate current-driven switching performance of pMTJ including switching time and power,and their dependence on perpendicular magnetic anisotropy and damping constant of the free layer by SPICE-based circuit *** results show that the pMTJ cells exhibit a less than 1 ns switching time and write energies lity factor■73 can be easily transformed into spin-torque nano-oscillators from magnetic memory as microwave sources or detectors for telecommunication devices.

关键词： magnetic tunnel junctions magnetic tunnel junction(MTJ)model switching time spin torque nano-oscillator

基于分支定界法的电能表计量电路容差设计方法

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电力自动化设备 2016年第5期36卷 102-107页

作者：李求洋李新王淑娟哈尔滨工业大学电气工程及自动化学院黑龙江哈尔滨150001 哈尔滨建成集团有限公司黑龙江哈尔滨150030

结合单相智能电能表计量电能准确度要求高的特点,建立描述批次单相智能电能表基本误差一致性的模型,提出相应的容差设计优化目标及约束条件。利用整数规划思想,提出一种面向离散型设计变量的容差设计方法。在此基础上,以加工成本作为优... 详细信息

结合单相智能电能表计量电能准确度要求高的特点,建立描述批次单相智能电能表基本误差一致性的模型,提出相应的容差设计优化目标及约束条件。利用整数规划思想,提出一种面向离散型设计变量的容差设计方法。在此基础上,以加工成本作为优化目标、计量误差的变化范围作为约束条件,对某型号单相智能电能表的计量电路进行容差设计优化。通过设置不同的误差变化范围界限值,获得相应的元器件公差等级和成本值。优化结果表明,所提方法在控制误差变化范围的同时,有效地将成本最小化,适用于单相智能电能表计量电路的容差设计。

关键词：单相智能电能表容差设计整数规划分支定界算法设计优化 “成本-公差”模型

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周刚水彩画的本土与现实追求

美术 2021年第8期644卷 142-143页

作者：李秋阳黑龙江工程学院艺术与设计学院

在西方绘画思潮的影响下,中国水彩画艺术的边界不断延伸,绘画题材与创作态度也愈加丰富、包容。但在传统认知里,水彩画因其水的流动性、颜料的透明性等特质,不宜制作大幅作品,只适合创作如风景、静物等清新明快的小幅画作。水彩画媒材... 详细信息

在西方绘画思潮的影响下,中国水彩画艺术的边界不断延伸,绘画题材与创作态度也愈加丰富、包容。但在传统认知里,水彩画因其水的流动性、颜料的透明性等特质,不宜制作大幅作品,只适合创作如风景、静物等清新明快的小幅画作。水彩画媒材的独特、技法的繁难,以及其通透、明澈的绘画效果使其在表现厚重、深刻的社会现实主题上略显单薄,而这一切也导致了水彩画艺术一直处于绘画领域的边缘地位。

关键词：水彩画艺术绘画领域绘画题材绘画效果西方绘画创作态度边缘地位清新明快

考虑寄生参数影响的芯片RC-HBM静电测试模型

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电力系统保护与控制 2022年第4期50卷 172-179页

作者：熊素琴李求洋肖志强中国电力科学研究院有限公司北京100192 湖南大学电气与信息工程学院湖南长沙410082

采用常规的人体模型(Human Body Model,HBM)进行静电释放(Electro-Static Discharge,ESD)测试时往往容易受到寄生参数的影响,使得电源芯片抗静电能力测量值与实际抗静电能力存在偏差,导致劣质产品通过HBM ESD测试,影响电源芯片产品良品... 详细信息

采用常规的人体模型(Human Body Model,HBM)进行静电释放(Electro-Static Discharge,ESD)测试时往往容易受到寄生参数的影响,使得电源芯片抗静电能力测量值与实际抗静电能力存在偏差,导致劣质产品通过HBM ESD测试,影响电源芯片产品良品率的提升。为此,提出了一种RC-HBM模型,通过引入RC并联支路,校正因寄生参数引起的静电放电电流的偏差,满足电源芯片静电可靠性测试的要求。首先阐述了静电对电源芯片的损坏机理。其次,分析了寄生参数对ESD电流的影响,阐述了常规HBM ESD测试的局限性。并提出了一种新型的RC-HBM模型,给出了RC并联支路参数的设计依据。最后,通过批量实验验证了所提RC-HBM模型的准确性和合理性。

关键词：电源芯片 HBM模型 ESD 寄生参数静电放电电流

Transformative Learning:Intercultural Adaptation of Chinese Teachers at the Confucius Institute in Spain

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Chinese Journal of Applied linguistics 2022年第2期45卷 294-315,318页

作者： Óscar FERNÁNDEZ-ÁLVAREZ qiuyang li Chen CHEN Faculty of Humanity León UniversitySpain School of Foreign Languages Tianjin Normal University College of International Education and Exchange Tianjin Normal University

In recent years there has been a proliferation of studies demonstrating the value of teaching abroad as much for its benefits for the training and professional development of these teachers,as for its impact and beneficial effects on *** article uses transformative learning as a theoretical framework to interpret the achievements associated with the experience of teaching abroad,and to identify and analyze different motivational factors,adjustments,changes,challenges,and perspectives of Chinese teachers linked to a Confucius Institute in Spain,through a qualitative analysis of narratives elicited through in-depth interviews and focus *** highlights the role and potential of the transnational,intercultural experience of these teachers as authentic actors in the part played by the Confucius Institutes in language teaching and the promotion of Chinese culture,indicating many issues including language difficulties,professional adjustment,ideas about education,beliefs of teachers and the management of the program.

关键词： Confucius Institute intercultural adaptation transformative learning teacher training