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High-Efficiency Dynamic Terahertz Deflector Utilizing a Mechanically Tunable Metasurface

Research 2024年第3期2023卷 585-594页

作者： Zhenci Sun Chao Liang Chen Chen xiayu wang Enze Zhou Xiaomeng Bian Yuanmu Yang Rui You Xiaoguang Zhao Jiahao Zhao Zheng You Department of Precision Instrument Tsinghua UniversityBeijing 100084China State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua UniversityBeijing 100084China Beijing Advanced Innovation Center for Integrated Circuits Beijing 100084China School of Instrument Science and Opto-Electronic Engineering Beijing Information Science and Technology UniversityBeijing 100016China.

Terahertz (THz) wave manipulation, especially the beam deflection, plays an essential role in various applications, such as next-generation communication, space exploration, and high-resolution imaging. Current THz optical components and devices are hampered by their large bulk sizes and passive responses, limiting the development of high-performance, miniaturized THz microsystems. Tunable metasurfaces offer a powerful dynamic optical platform for controlling the propagation of electromagnetic waves. In this article, we presented a mechanically tunable metasurface (MTM), which can achieve terahertz beam deflection and vary the intensity of the anomalous reflected terahertz wave by changing the air gap between the metallic resonator (MR) array with phase discontinuities and Au ground plane. The absence of lossy spacer materials substantially enhances deflection efficiency. The device was fabricated by a combination of the surface and bulk-micromachining processes. The THz beam steering capability was characterized using terahertz time domain spectroscopy. When the air gap is 50 μm, the maximum deflection coefficient reaches 0.60 at 0.61 THz with a deflection angle of ~44.5°, consistent with theoretical predictions. We further established an electrically tunable miniaturized THz device for dynamic beam steering by introducing a micro voice coil motor to control the air gap continuously. It is shown that our designed MTM demonstrates a high modulation depth of deflection coefficient (~ 62.5%) in the target steered angle at the operating frequency. Our results showcase the potential of the proposed MTM as a platform for high-efficiency THz beam manipulation.

关键词： tunable Efficiency resonator

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Dual-channel mechano-phosphorescence:a combined locking effect with twisted molecular structures and robust interactions

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Light(Science & Applications) 2024年第4期13卷 738-746页

作者： Zongliang Xie Zhu Mao Hailan wang Yuxin Xiao xiayu Zhang Tao Yu Zhongfu An Wei Huang Frontiers Science Center for Flexible Electronics Xi’an Institute of Flexible Electronics&Xi’an Institute of Biomedical Materials and EngineeringNorthwestern Polytechnical University127 West Youyi RoadXi’an 710072China. Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518100China. Shenzhen Institutes of Advanced Electronic Materials Shenzhen 518100China. Key Laboratory of Flexible Electronics&Institute of Advanced Materials Nanjing Tech University30 South Puzhu RoadNanjing 211816China

Organic mechanoluminescence materials,featuring dual emission and ultralong phosphorescence characteristics,exhibit significant potential for applications in real-time stress sensing,pressure-sensitive lighting,advanced security marking techniques,and material breakage ***,due to immature molecular design strategies and unclear luminescence mechanisms,these materials remain rarely *** this study,we propose a valuable molecular design strategy to achieve dual-channel *** introducing the arylphosphine oxide group into a highly twisted molecular framework,enhanced intra-and intermolecular interactions could be achieved within rigid structures,leading to dual-channel mechanoluminescence with greatly promoted ultralong *** investigations reveal the substantial boosting effect of intra-and intermolecular interactions on mechanoluminescence and ultralong phosphorescence properties by locking the highly twisted molecular *** work provides a concise and guiding route to develop novel smart responsive luminescence materials for widespread applications in material science.

关键词： channel luminescence locking

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Preparation and rheological behaviors of PA6/SiO_(2) nanocompiste

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Frontiers of Chemical Science and Engineering 2007年第4期1卷 332-337页

作者： WEI Shanshan LIU Yuejun LI Xianggang HUANG Yugang wang xiayu ZHANG Ping College of Packaging and Printing Hunan University of TechnologyZhuzhou 412008China The Institute of Polymer Science Xiangtan UniversityXiangtan 411105China College of Civil Engineering and Mechanics Xiangtan UniversityXiangtan 411105China

The polyamide 6(PA6)/SiO_(2) nanocomposites were prepared by in situ polymerization and the rheological behaviors were *** morphology of resultant materials was characterized by scanning electron microscopy(SEM)and the rheological behaviors were characterized by capillary *** results showed that the SiO_(2) particle size was around 50 nm and the particles dispersed evenly in PA6 *** nanocomposites were pesudoplastic fluids and the apparent viscosities of nanocomposites increased initially and then decreased with the increase in nano-SiO_(2) content at the same *** non-Newtonian indexes of nanocomposites were smaller than those of pure *** the increase in nano-SiO_(2) content the apparent viscous activation energies of nanocomposites increased initially and then *** rheological behaviors revealed that there were strong interactions between PA6 macromolecule chains and nano-SiO_(2) particles.

关键词： Nylon 6 nano-silica rheological behavior nanocomposite

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Y型星形杂臂甲壳型液晶聚合物的合成及其液晶行为研究

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化学学报 2011年第8期69卷 993-998页

作者：陈建芳凌爱华王霞瑜湖南工程学院化学化工学院湘潭411104 湘潭大学化学学院高分子材料研究所湘潭411105

通过原子转移自由基聚合(ATRP)与ATRP衍生物化学修饰结合的方法,合成了含一条聚苯乙烯(PS)臂、两条聚[乙烯基对苯二甲酸二(对甲氧基苯酚)酯](PMPCS)臂的Y型星形杂臂甲壳型液晶聚合物PS(PMPCS)2.采用核磁共振谱(1H NMR)和凝胶渗透色谱(G... 详细信息

通过原子转移自由基聚合(ATRP)与ATRP衍生物化学修饰结合的方法,合成了含一条聚苯乙烯(PS)臂、两条聚[乙烯基对苯二甲酸二(对甲氧基苯酚)酯](PMPCS)臂的Y型星形杂臂甲壳型液晶聚合物PS(PMPCS)2.采用核磁共振谱(1H NMR)和凝胶渗透色谱(GPC)手段确定了聚合物的基本结构,所得聚合物为接近单分散的星形杂臂聚合物.采用热分析(DSC)、热台偏光显微镜(POM)和X衍射仪(WXAD)研究了此类星形杂臂共聚物的热致液晶行为.液晶性研究显示,其液晶性与刚性链段PMPCS的长度密切相关,只有当杂臂共聚物中刚性PMPCS链段达到一定长度后才出现液晶性.

关键词：星形杂臂原子转移自由基聚合(ATRP) 甲壳型液晶液晶行为

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互联网对个人健康的积极影响及其形成机制:社会关系网络的作用

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华东理工大学学报（社会科学版） 2022年第1期37卷 66-80页

作者：王元超王夏雨中国人民大学社会学理论与方法研究中心北京100872

随着互联网对于人类社会的影响愈加广泛,其对于个人健康状况的影响已成为亟须讨论的重要问题。本文基于中国综合社会调查(C G SS)2012年数据,使用倾向值加权法探究了互联网使用对于个人健康状况的影响及其形成机制。研究发现,互联网使... 详细信息

随着互联网对于人类社会的影响愈加广泛,其对于个人健康状况的影响已成为亟须讨论的重要问题。本文基于中国综合社会调查(C G SS)2012年数据,使用倾向值加权法探究了互联网使用对于个人健康状况的影响及其形成机制。研究发现,互联网使用对于个人健康状况具有显著的积极影响。这一影响机制是通过社会关系网络实现的:互联网使用有利于扩展社会关系网络的规模,从而为个人提供更多的社会支持和情感慰藉,也有助于缓解压力生活事件带来的紧张状态,帮助个人获得更多健康信息与医疗资源,进而提高个人健康水平。

关键词：互联网健康生活方式社会关系网络

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马克思的全球化视野及其当代意义

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江西社会科学 2022年第2期42卷 13-20,206页

作者：陈劲松王夏雨中国人民大学社会与人口学院北京海淀100872

马克思关于全球化的系统论述,为我们参与全球化进程并积极应对各种“逆全球化”论调提供了深刻的理论指导。马克思用“世界历史”的概念充分表达了他对人类全球化进程及其水平的深刻洞察,即全球化意味着历史越来越多地呈现为世界历史。... 详细信息

马克思关于全球化的系统论述,为我们参与全球化进程并积极应对各种“逆全球化”论调提供了深刻的理论指导。马克思用“世界历史”的概念充分表达了他对人类全球化进程及其水平的深刻洞察,即全球化意味着历史越来越多地呈现为世界历史。马克思认为,创造世界历史的动力是人类的生产和交往活动,全球化的根本动力是生产和交往的普遍发展。马克思站在世界历史的高度,指出世界上一切落后民族或国家都将被迫纳入资本主义生产方式进行改造,深刻论述了资本主义的历史合理性及其局限性。马克思认为世界历史的未来与无产阶级的历史使命紧密相关,全球化的真正承担者是无产阶级,全球化为人类的最终解放和全球命运共同体的最终形成奠定了物质与精神基础。

关键词：马克思全球化人类命运共同体脱钩

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SYNTHESIS AND CHARACTERIZATION OF AMPHIPHILIC TRIBLOCK COPOLYMER PEO-b-PMMA-b-PS

SYNTHESIS AND CHARACTERIZATION OF AMPHIPHILIC TRIBLOCK COPOL...

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Third East Asian Polymer Conference

作者： Xiaovi Sun, Qiqun He, Hailiang Zhang, xiayu wang Institute of Polymer Science, Xiangtan University, Xiangtan 411105

Living polymerization procedures in the ideal case exert immediate initiation followed by propagation without termination and transfer reaction. Therefore these procedures are qualified synthetic tools for obtaining polymers with well defined architecture, especially block copolymers. Amphiphilic block copolymers have attracted special attention in fundamental and applied research for their unique chain architecture and physical properties. Poly(ethylene oxide) (PEO) which has superior properties for being nontoxic, flexible, hydrophilic and biocompatible, is widely used in research and application. Amphiphilic block copolymers consisting of PEO as the hydrophilic and crystallizable segments are particularly popular. The synthesis of ternary ABC triblock copolymers by living polymerizaion has been one of the most interesting field to study their rich morphological

关键词： Triblock copolymer atom transfer radical polymerization.

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岩溶区水生生态系统微藻的生物碳泵效应

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微生物学报 2019年第6期59卷 1012-1025页

作者：严壮汪夏雨李为余龙江华中科技大学生命科学与技术学院生物技术系资源生物学与生物技术研究所湖北武汉430074 分子生物物理教育部重点实验室湖北武汉430074

微藻在水生生态系统的碳固定中扮演重要角色。本文综述了岩溶区水生生态系统生物碳泵的提出、岩溶区微藻生物碳泵作用、影响微藻固碳的主要环境因素以及岩溶区微藻固碳的研究进展,并提出了亟待解决的关键科学问题,为深入研究岩溶区水生... 详细信息

微藻在水生生态系统的碳固定中扮演重要角色。本文综述了岩溶区水生生态系统生物碳泵的提出、岩溶区微藻生物碳泵作用、影响微藻固碳的主要环境因素以及岩溶区微藻固碳的研究进展,并提出了亟待解决的关键科学问题,为深入研究岩溶区水生生态系统微藻固碳能力及生物碳泵机制、科学认识岩溶生态系统的碳汇潜力、丰富和完善岩溶碳循环理论提供参考。

关键词：岩溶区水生生态系统微藻固碳生物碳泵效应环境因素

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AB_2型星形杂臂偶氮液晶聚合物的合成及表征

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高分子学报 2006年第2期16卷 314-319页

作者：陈建芳张海良刘敏娜王霞瑜湘潭大学化学学院高分子材料研究所

通过原子转移自由基聚合(ATRP)与ATRP衍生物化学修饰结合的方法,合成了一系列AB2型星形杂臂偶氮液晶聚合物.其中,A为聚苯乙烯,B为聚6-[4-(4′-甲氧基苯基)偶氮苯氧基己酯](PMMAZO).合成分三步进行.首先,以ATRP方法得到ω-溴聚苯乙烯活性... 详细信息

通过原子转移自由基聚合(ATRP)与ATRP衍生物化学修饰结合的方法,合成了一系列AB2型星形杂臂偶氮液晶聚合物.其中,A为聚苯乙烯,B为聚6-[4-(4′-甲氧基苯基)偶氮苯氧基己酯](PMMAZO).合成分三步进行.首先,以ATRP方法得到ω-溴聚苯乙烯活性链PS(Br).然后对PS(Br)进行化学改性,得到带两个末端溴原子的聚苯乙烯活性链PS(Br)2·最后,以PS(Br)2作为双官能团大分子引发剂,引发6-[4-(4′-甲氧基苯基)偶氮苯氧基]己酯(MMAZO)发生ATRP聚合,得到星形杂臂PS(PMMAZO)2聚合物.进一步对聚合产物进行了GPC和1H-NMR分析.结果表明合成产物是预期的星形杂臂聚合物,产物分子量可控且分子量分布狭窄.同时,以DSC和POM表征了星形杂臂聚合物的液晶性.

关键词：星形杂臂聚合物原子转移自由基聚合(ATRP) 偶氮聚合物液晶

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MicroRNA-21, 204 and 125b Play Potential Roles in Tumorigenesis of Melanoma

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Advances in Bioscience and Biotechnology 2015年第12期6卷 677-692页

作者： Chengtan Li xiayu wang Ya’ni Chen Xiaohua Tan Wen Li Sheng Yan Weibin Cai Xianrong Xu Liangwen Xu Lei Yang Yutao Yan School of Medicine Hangzhou Normal University Hangzhou China IHRC Inc. Atlanta GA USA

Aim: The high mortality rate of melanoma is due to partially the lack of good diagnostic markers and treatment strategies. Over the past several years, several microRNA (miRNA) profiling studies have been performed on melanoma tissues, but with extremely inconsistency, the diagnostic value of miRNA candidates in melanoma remains under debate. Thus, this study aims to systematically evaluate the consistency of miRNAs tissue in multiple independent studies in melanoma. Method: Eligible studies were screened and selected from the PubMed, EMBASE, and Web of Science. A systematic analysis of published miRNA expression studies that compared the miRNA expression profiles between melanoma tissues and normal skin tissue was conducted. A vote-counting strategy was followed with the collection of information. Real time PCRs were employed to validate miRNA candidates with high consistency. Targets of consistent miRNAs were predicted by online programs (like miRTarBase, *** and TargetScanHuman 6.2). Enrichment analyses for gene ontology (GO) terms and Kyoto encyclopedia of genes and genomes (KEGG) pathways were carried out with Database for Annotation, Visualization, and Integrated Discovery (DAVID). Results: A total of 303 differentially expressed miRNAs were reported in the 10 miRNA-profiling studies during comparison of melanoma tissues with normal tissues;132 were up-regulated in melanoma, and 171 were down-regulated. However, in the group of consistently reported miRNAs (cutoff > 3 times), only moderate numbers of consistent and differentially expressed miRNAs were selected. miRNA-21 was found increased in 5 different studies, miRNA-146b, miRNA-17 and miRNA-18a were reported up-regulated in 4 profiling studies. Meanwhile, miRNA-204 and miRNA-125b were found down-regulated in 5 studies, miRNA-141, miRNA-149, miRNA-224, miRNA-200b, miRNA-200c were consistently decreased in just 4 out of 10 profiling studies in total. The directions of differential expression of these

关键词： Melanoma miRNA Systematic Analysis Programmed Cell Death Transcription

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