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Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 148-155页

作者： Yunhan Yang han Jia Tuo liu Yuzhen Yang Jun Yang Key Laboratory of Noise and Vibration Research Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

The phenomenon of induced transparency, characterized by a high quality(Q) factor, holds significant importance in the fields of high-precision sensing, energy storage and wave manipulation. Conventional transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters, thereby hindering advanced research on high-Q effects. Here we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection spectrum. By virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom, we achieve the manipulation of induced transparency in a decoupled, wide-ranging, and elaborate manner. Exploiting the diverse evolutions across the intrinsic parameter space, we show experimentally a counter-intuitive increase in the Q-factor of the transparency window, which is attributed to the enhanced dissipation of the bright ***, a constant group delay at the center frequency is observed accompanying this evolution. Our work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon, and paves the way towards applications in programmable acoustic sensors, filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter

基于面元法的分布式涵道推进系统进气道优化设计

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推进技术 2021年第11期42卷 2465-2473页

作者：王海童王掩刚周芳刘汉儒西北工业大学动力与能源学院陕西西安710129 西北工业大学深圳研究院广东深圳518057

分布式涵道推进系统被认为是一种高效率的动力布局形式,其中进气道如何使气流低损失地快速过渡到数个圆形截面的涵道风扇进口是一个亟需探索的设计问题。以分布式涵道推进系统进气道过渡段为研究对象,基于面元计算方法,发展了一种进气... 详细信息

分布式涵道推进系统被认为是一种高效率的动力布局形式,其中进气道如何使气流低损失地快速过渡到数个圆形截面的涵道风扇进口是一个亟需探索的设计问题。以分布式涵道推进系统进气道过渡段为研究对象,基于面元计算方法,发展了一种进气道内流动的快速数值预测手段。应用所发展面元法数值方法结合进气道的超椭圆参数化方法、自适应优化算法,建立了分布式涵道推进系统进气道的无经验优化设计方法。以某型悬停状态的分布式涵道推进垂直起降飞行器为例,使用该设计方法实现了从无圆滑过渡的简单初始几何到气动指标符合优化预期的光顺几何的优化设计。基于RANS的三维数值分析表明:所优化设计的进气道相比于初始几何总压畸变系数(DC)从0.0086降低到0.0067,低于基于经验设计的参考几何(DC=0.0073),且流场无明显分离及旋涡,确认了这种具有高时间效率的无经验设计方法的有效性。

关键词：面元法分布式推进进气道优化畸变

Preparation and applications of calcium ferrite as a functional material:A review

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 292-310页

作者： Xiuli han Bowen Duan Lei liu Shilong Fang Weiwei Wang College of Mining Engineering North China University of Science and TechnologyTangshan 063210China Collaborative Innovation Center of Green Development and Ecological Restoration of Mineral Resources of Hebei Province Tangshan 063210China Key Laboratory of Mining Development and Security Technology of Hebei Province Tangshan 063210China

Calcium ferrite(CF)is recognized as a potential green and efficient functional material because of its advantages of magnetism,electrochemistry,catalysis,and biocompatibility in the fields of materials chemistry,environmental engineering,and ***-fore,the obtained research results need to be systematically summarized,and new perspectives on CF and its composite materials need to be *** on the presented studies of CF and its composite materials,the types and structures of the crystal are *** addition,the current application technologies and theoretical mechanisms with various properties in different fields are ***,the various preparation methods of CF and its composite materials are elaborated in *** importantly,the advantages and disadvantages of the synthesis methods of CF and its composite materials are discussed,and the existing problems and emerging challenges in practical production are ***,the key future research directions of CF and its composite materials have been prospected from the potential application technologies to provide references for its synthesis and efficient utilization.

关键词： calcium ferrite mineral functional materials preparation application perspectives

串列叶栅缝隙射流对分离流动及叶栅性能影响的研究

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推进技术 2018年第12期39卷 2728-2736页

作者：刘汉儒岳少原王掩刚张俊西北工业大学动力与能源学院陕西西安710072

为了研究串列叶栅前后叶缝隙流作用对流动分离和叶栅性能影响机制,通过非定常数值计算分析了串列叶栅轴向重合度和节距系数两种缝隙参数组合对高负荷压气机串列叶栅在大攻角11°下性能影响以及缝隙流掺混作用下前后叶流动分离的时空演... 详细信息

为了研究串列叶栅前后叶缝隙流作用对流动分离和叶栅性能影响机制,通过非定常数值计算分析了串列叶栅轴向重合度和节距系数两种缝隙参数组合对高负荷压气机串列叶栅在大攻角11°下性能影响以及缝隙流掺混作用下前后叶流动分离的时空演化机制的影响规律,并且提出了缝隙流对串列叶栅流动及性能影响的综合性参数-缝隙收缩比。研究结果表明:轴向重合度在-0.022～0.023,节距系数在0.6～0.9时,串列叶栅能取得较好气动性能;在缝隙非定常吹除作用下,后叶吸力面分离泡被周期性抑制,前叶吸力面分离泡受缝隙射流源的影响较弱;提出的缝隙收缩比作为综合匹配参数可以更清晰揭示出串列叶栅有效工作条件,在亚声速来流工况下,缝隙收缩比大于1是串列叶片能正常工作的前提,缝隙收缩比小于1,缝隙加速作用消失,叶栅性能较差,最佳的缝隙收缩比范围是1.1～1.4。

关键词：串列叶栅非定常流动分离泡压力波动特征缝隙收缩比

Performance Analysis of a Coupled System based on Organic Rankine Cycle and Double Effect Absorption Refrigeration for Waste Heat Recovery in Data Center

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Journal of Thermal Science 2025年第1期34卷 188-205页

作者： LI Peng XU Jiaqi WANG Binbin liu Jianyang ZHAO Wensheng han Zhonghe School of Energy Power and Mechanical Engineering North China Electric Power University Hebei Key Laboratory of Low Carbon and High Efficiency Power Generation Technology North China Electric Power University

During data center operation,it generates a significant volume of low-grade waste *** recover waste heat,a coupled system including solar collector,double effect absorption refrigeration and organic Rankine cycle is *** system performance is analyzed in *** the organic Rankine cycle,five organic working fluids(R245fa,R245ca,R123,R11,and R113) are selected.R245fa,R113 and R245ca obtain the maximum net power output,thermal efficiency and exergy efficiency,*** the double effect absorption refrigeration system,the evaporation temperature,condensation temperature,and generation pressure affect the COP and exergy *** the generator pressure is unchanged,the COP increases with increasing evaporation temperature and decreasing condensation *** the COP reaches 1.3,the COP slightly decreases as the evaporation temperature or condensation temperature ***,the exergy efficiency of refrigeration systems exhibits the same trend as the COP,and the exergy efficiency maximum value appears at approximately 0.32.A new performance indicator,rPUE,was defined to evaluate the data center power utilization *** flow distribution ratio and heat source temperature were optimized with multi-objective *** the mass flow distribution rate is 0.6 and the heat source temperature is 441.5 K,rPUE and the total unit production costs of the system obtain the optimal solution.

关键词： Exergy

Deep eutectic solvents for separation and purification applications in critical metal metallurgy:Recent advances and perspectives

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 1-19页

作者： Shuo Chen Shengpeng Su Yanfang Huang Bingbing liu Hu Sun Shuzhen Yang Guihong han School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China Zhongyuan Critical Metals Laboratory Henan ProvinceZhengzhou 450001China

Solvent extraction,a separation and purification technology,is crucial in critical metal *** solvents commonly used in solvent extraction exhibit disadvantages,such as high volatility,high toxicity,and flammability,causing a spectrum of hazards to human health and environmental *** solvents have been recognized as potential alternatives to these harmful organic *** the past two decades,several neoteric solvents have been proposed,including ionic liquids(ILs)and deep eutectic solvents(DESs).DESs have gradually become the focus of green solvents owing to several advantages,namely,low toxicity,degradability,and low *** this critical review,their classification,formation mechanisms,preparation methods,characterization technologies,and special physicochemical properties based on the most recent advancements in research have been systematically ***,the major separation and purification applications of DESs in critical metal metallurgy were comprehensively ***,future opportunities and challenges of DESs were explored in the current research *** conclusion,this review provides valuable insights for improving our overall understanding of DESs,and it holds important potential for expanding separation and purification applications in critical metal metallurgy.

关键词： deep eutectic solvents preparations properties separation and purification critical metal metallurgy

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募集资金投向变更对上市公司绩效的影响研究

中小企业管理与科技 2019年第27期3卷 52-55页

作者：刘函如石河子大学

融资是证券市场的一个基本功能,上市公司为了自身的可持续发展,都会选择在证券市场中募集资金。募集资金的使用效率会对企业自身的经营产生影响。论文以国内有关上市公司募集资金投向变更的研究为基础,分析了上市公司募集资金变更投向... 详细信息

融资是证券市场的一个基本功能,上市公司为了自身的可持续发展,都会选择在证券市场中募集资金。募集资金的使用效率会对企业自身的经营产生影响。论文以国内有关上市公司募集资金投向变更的研究为基础,分析了上市公司募集资金变更投向的现状,说明了其募集资金的实际使用情况,阐述了导致募集资金变更的原因,并进一步分析了变更募投项目对企业绩效的影响。最后得出变更募集资金投向是一种低效率的资金使用行为。

关键词：募集资金投向变更企业绩效

Flexible Graphene Field‑Effect Transistors and Their Application in Flexible Biomedical Sensing

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Nano-Micro Letters 2025年第2期17卷 252-313页

作者： Mingyuan Sun Shuai Wang Yanbo Liang Chao Wang Yunhong Zhang Hong liu Yu Zhang Lin han Institute of Marine Science and Technology Shandong UniversityQingdao 266237ShandongPeople’s Republic of China State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100ShandongPeople’s Republic of China School of Integrated Circuits Shandong UniversityJinan 250100ShandongPeople’s Republic of China Shandong Engineering Research Center of Biomarker and Artificial Intelligence Application Jinan250100ShandongPeople’s Republic of China

Flexible electronics are transforming our lives by making daily activities more *** to this innovation are field-effect transistors(FETs),valued for their efficient signal processing,nanoscale fabrication,low-power consumption,fast response times,and ***,known for its exceptional mechanical properties,high electron mobility,and biocompatibility,is an ideal material for FET channels and *** combination of graphene and FETs has given rise to flexible graphene field-effect transistors(FGFETs),driving significant advances in flexible electronics and sparked a strong interest in flexible biomedical ***,we first provide a brief overview of the basic structure,operating mechanism,and evaluation parameters of FGFETs,and delve into their material selection and patterning *** ability of FGFETs to sense strains and biomolecular charges opens up diverse application *** specifically analyze the latest strategies for integrating FGFETs into wearable and implantable flexible biomedical sensors,focusing on the key aspects of constructing high-quality flexible biomedical ***,we discuss the current challenges and prospects of FGFETs and their applications in biomedical *** review will provide valuable insights and inspiration for ongoing research to improve the quality of FGFETs and broaden their application prospects in flexible biomedical sensing.

关键词： Flexible Graphene Field-effect transistor Wearable Implantable Biosensor

Novel flexible and transparent microstrip low-pass filter design with Π-shaped DGS

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The Journal of China Universities of Posts and Telecommunications 2025年

作者： liu Zhaohan han Yunan Qiu Xianbo Li Xianli College of Information Science and Technology， Beijing University of Chemical Technology

This paper proposes a new design for a transparent low-pass filter (LPF) using a flexible PTFE material and metallic copper. The transparent microstrip filter employs an asymmetric Π-shaped structure with dimensions of 260 mm × 13 mm × 0.148 mm， which owns a narrow transition band and achieves an insertion loss of less than 1.0 dB below 0.26 GHz. Furthermore， the insertion loss of the transparent microstrip filter can exceed 30 dB in the stopband of 1.02 GHz to 6.50 GHz. Square holes are added to the copper layer to improve the transparency of the LPF， and the filter performance can be adjusted by changing the square hole area and resolution. Additionally， multiple identical structures are cascaded to increase the insertion loss in the stopband while maintaining the passband. The transparent microstrip LPF has the characteristics of flexibility， high transparency， and significant insertion loss in the stopband， making it suitable for applications that require electromagnetic protection in a clear field of vision.

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