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金属膜圆孔阵列异常透射特性的波导机制

光学学报 2022年第4期42卷 220-228页

作者：薛润玉王正宇王正岭江苏大学物理与电子工程学院江苏镇江212013

对线偏振平面波垂直入射到亚微米金属膜圆孔阵列的透射谱进行了研究,优化结构参数后得到的最大透射率可达0.896,远大于圆孔阵列的孔填充比,突破了传统理论的预期。对金属膜圆孔阵列的电场分布、波导模式、相位特征及色散关系等进行了分... 详细信息

对线偏振平面波垂直入射到亚微米金属膜圆孔阵列的透射谱进行了研究,优化结构参数后得到的最大透射率可达0.896,远大于圆孔阵列的孔填充比,突破了传统理论的预期。对金属膜圆孔阵列的电场分布、波导模式、相位特征及色散关系等进行了分析,研究了基于金属膜圆孔波导的异常透射机制。研究发现,表面Bloch波的存在使得金属膜圆孔阵列的上方形成了一套二维周期性的光晶格,并且光晶格的电场分布中心正好在金属膜圆孔部分的上方。当光晶格的电场模式与圆孔中的横向本征电场模式匹配时,将导致较大的耦合效率。如果电场模式沿着圆孔传播时满足相位匹配条件,就能保证圆孔中的光能从圆孔中有效地耦合出来,进而形成较大的透射率。该机制不但可以解释较厚的二维金属膜圆孔阵列的光频段异常透射现象,而且适用于太赫兹波段。如果在圆孔中填充大折射率介质,还可以实现波长远大于孔半径情况下的较大透射率。

关键词：薄膜圆孔阵列透射机制模式特性圆孔波导

Construction of a Metallacyclopentadiene Ring through the Attack of Carbanions to M≡C Bond Followed by C—H Activation

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Chinese Journal of Chemistry 2024年第3期42卷 235-242页

作者： Chun Tang Shengjie Zhang zhengyu Lu Qian Li Ming Luo Dafa Chen Haiping Xia State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringCollaborative Innovation Center of Chemistry for Energy MaterialsXiamen UniversityXiamenFujian361005 China Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis Department of ChemistrySouthern University of Science and TechnologyShenzhenGuangdong518055 China

Metallacyclopentadienes are important metallacycles and regarded as intermediates in many reactions,therefore,new methods to achieve them are *** this study,a formal[3+2]method,through the reactions of an osmapentalyne with benzyl carbanions,was *** reactions underwent a nucleophilic attack of carbanions to the Os≡C bond,followed by C—H activation to form the five-membered osmacyclopentadiene *** of the reactions were carried out at room temperature,the substituents on the aromatic rings of benzyl carbanions are diverse,and the resulting products contain an Os—H bond,representing a novel type of 10C-carbolong *** work provides a new convenient route to construct metallacyclopentadienes,which is expected to further promote the development of such a type of substances.

关键词： Metallacyclopentadiene Carbolong chemistry Osmium C–H activation Nucleophilic addition

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我国农村金融发展对城乡收入差距的影响

改革与战略 2017年第10期33卷 129-132页

作者：王正宇湖北文理学院湖北襄阳441053

我国城乡发展失调,有历史、政策、制度、金融等方面的原因。经济发展与金融发展密切相关。农村金融的发展能够有效提升农村地区资本的集聚,带动该地区资源配置效率与技术的提高,从而推动农村地区的经济发展,增加农民经济收入。为此,应... 详细信息

我国城乡发展失调,有历史、政策、制度、金融等方面的原因。经济发展与金融发展密切相关。农村金融的发展能够有效提升农村地区资本的集聚,带动该地区资源配置效率与技术的提高,从而推动农村地区的经济发展,增加农民经济收入。为此,应制定适合农村金融发展的政策制度,扩大农村资金投放,制定农村金融激励制度,取消金融机构对农民的贷款门槛等,以抑制城乡差距继续扩大。

关键词：农村金融发展城乡收入差距影响作用

Toward understanding the role of genomic repeat elements in neurodegenerative diseases

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Neural Regeneration Research 2025年第3期20卷 646-659页

作者： zhengyu An Aidi Jiang Jingqi Chen Institute of Science and Technology for Brain-Inspired Intelligence Fudan UniversityShanghaiChina MOE Frontiers Center for Brain Science Fudan UniversityShanghaiChina MOE Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence Fudan UniversityShanghaiChina Zhangjiang Fudan International Innovation Center ShanghaiChina

Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage sequencing technology, researchers have started to notice that genomic repeat regions, previously neglected in search of disease culprits, are active contributors to multiple neurodegenerative diseases. In this review, we describe the association between repeat element variants and multiple degenerative diseases through genome-wide association studies and targeted sequencing. We discuss the identification of disease-relevant repeat element variants, further powered by the advancement of long-read sequencing technologies and their related tools, and summarize recent findings in the molecular mechanisms of repeat element variants in brain degeneration, such as those causing transcriptional silencing or RNA-mediated gain of toxic function. Furthermore, we describe how in silico predictions using innovative computational models, such as deep learning language models, could enhance and accelerate our understanding of the functional impact of repeat element variants. Finally, we discuss future directions to advance current findings for a better understanding of neurodegenerative diseases and the clinical applications of genomic repeat elements.

关键词： Alzheimer's disease ataxia deep learning long-read sequencing neurodegeneration neurodegenerative diseases Parkinson's disease repeat element structural variant

Unraveling the role of formate in improving nitrogen removal via coupled partial denitrification-anammox

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Frontiers of Environmental Science & Engineering 2024年第9期18卷 79-90页

作者： Wanlu Zhu Rui Xiao Min Xu Wenbo Chai Wenlong Liu zhengyu Jin David Ikumi Huijie Lu Key Laboratory of Environmental Remediation and Ecological Health(Ministry of Education) College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China China National Nuclear Corporation Beijing Research Institute of Chemical Engineering and MetallurgyBeijing 100029China College of Environment Zhejiang University of TechnologyHangzhou 310014China Key Laboratory of Ecology and Environment in Minority Areas National Ethnic Affairs CommissionCollege of Life&Environmental SciencesMinzu University of ChinaBeijing 100081China Water Research Group Department of Civil EngineeringUniversity of Cape TownRondebosch 7700South Africa Key Laboratory of Water Pollution Control and Environmental Safety Hangzhou 310058China

The addition of traditional carbon sources(e.g.,acetate)could favor heterotrophic overgrowth in partial denitrification coupled with anammox(PD–A)systems,thus hindering the performance and stability of this novel wastewater nitrogen removal ***,it is necessary to develop an effective,environmentally friendly,and inexpensive *** study demonstrated the potential of formate to enhance the performance and community stability of PD–A under mainstream *** a laboratory-scale biofilm reactor,formate addition(COD/NO_(3)^(–)–N=1.75)improved nitrogen removal efficiency(from 72.1±3.5%to 81.7±2.7%),EPS content(from 106.3±8.1 to 163.0±15.5 mg/gVSS)and increased anammox bacteria growth(predominantly Candidatus Brocadia,from 29.5±0.7%to 34.5±5.4%)while maintaining stable heterotrophs dominated by methylotrophic ***–NanoSIMS revealed a formate uptake using *** and Desulfobacillus,with *** being the major contributor to partial nitrate reduction to *** can synthesize diverse hydrophobic amino acids and provide key nutrients for *** achieve comparable nitrogen removal,the cost of the formate-driven PD–A process should be 11.2%lower than that of *** results greatly enrich our understanding of C1 metabolism represented by formate in anammox communities and its application in the context of coupling partial denitrification–anammox toward enhanced nitrogen removal in global wastewater treatment systems.

关键词： Formate Mixotrophic growth Partial denitrification-anammox Metabolic interaction FISH-NanoSIMS

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HXFA299型精梳机工艺试验探讨

棉纺织技术 2009年第10期37卷 38-40页

作者：汪振宇山东德源纱厂有限公司

探讨HXFA299型精梳机工艺性能。通过分析HXFA299型精梳机机构特点，对细绒棉CJ 9．7 tex及长绒棉CJ 7．3tex两类品种在SXFA289型精梳机上进行对比试验。结果表明：HXFA299型精梳机表现出较好的工艺性能，在保证精梳及成纱质量的前提下... 详细信息

探讨HXFA299型精梳机工艺性能。通过分析HXFA299型精梳机机构特点，对细绒棉CJ 9．7 tex及长绒棉CJ 7．3tex两类品种在SXFA289型精梳机上进行对比试验。结果表明：HXFA299型精梳机表现出较好的工艺性能，在保证精梳及成纱质量的前提下，可降低精梳落棉率1．5个百分点～4个百分点。加工细绒棉时能在400钳次/min下稳定运行，加工长绒棉时能在380钳次／min下稳定运行，精梳条质量无明显恶化。

关键词：精梳机落棉率速度短绒率 AFIS检测

External Characteristics Simulation of High-speed Rail Anti-snake Shock Absorber

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External Characteristics Simulation of High-speed Rail Anti-...

喷涂机器人矩形喷枪建模分析与迷彩图案全覆盖路径规划

2018中国汽车工程学会年会

作者： LIU Qiu SUN Jingwei HU Xu wang zhengyu GU Liang Beijing Institute of Technology

For the valve plate in high-speedrail anti-snake shock absorber,it is difficult to obtain analytical formulas for its deformation using only the principle of elastic ***,the finite element method and the principle of elastic mechanics are used to calculate the deformation of valve *** the same time,the mathematical model of shock absorber is established based on the actual structure of anti-snake shock absorber and the related theories of hydraulic fluid ***,the purpose of computer simulation of external characteristics of shock absorber is achieved by loading a certain excitation *** simulation and test results show that the calculation method of valve plate deformation and the established mathematical model are accurate and *** is of great significance to accurately calculate the deformation of valve plate under complex force conditions and to accurately model the shock absorber.

关键词： finite element method hydraulic shock absorbers parametric modeling simulation and experiment

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机器人 2023年第2期45卷 139-155,165页

作者：徐锋訾斌袁京然王正雨合肥工业大学机械工程学院安徽合肥230009

针对喷涂机器人迷彩涂装作业过程中边缘混色、圆弧过渡和无法实现多色精细化喷涂的问题,设计了一种具有直角边界、可防过喷的矩形喷枪,建立其涂料沉积模型。喷枪性能实验结果表明,改进后的矩形喷枪涂层厚度均匀,满足数码迷彩喷涂工艺需... 详细信息

针对喷涂机器人迷彩涂装作业过程中边缘混色、圆弧过渡和无法实现多色精细化喷涂的问题,设计了一种具有直角边界、可防过喷的矩形喷枪,建立其涂料沉积模型。喷枪性能实验结果表明,改进后的矩形喷枪涂层厚度均匀,满足数码迷彩喷涂工艺需求。其次,采用角点检测算法提取数码迷彩图案角点坐标,同时以角点坐标为基础,建立数码迷彩图案的平面栅格地图。然后,提出改进的生物激励神经网络(BINN)方法,引入融合数码迷彩喷涂工艺的机器人移动规则,将神经元活性传播方向限定为互相正交的4个方向,以缩小神经元动态激励场景范围,降低其计算复杂度。最后,采用基于矩阵变换的方法,将2维路径映射至车辆模型表面,生成3维迷彩喷涂路径。通过仿真与数码迷彩喷涂实验验证了所提方法的有效性,降低了生物激励神经网络的计算复杂度,解决了机器人喷涂过程中油漆过喷与数码迷彩喷涂路径难以规划的问题。

关键词：喷涂机器人数码迷彩全覆盖路径规划生物激励神经网络

一类不满足Pieper准则的机器人逆运动学解析解获取方法

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机器人 2016年第4期38卷 486-494页

作者：于凌涛王文杰王正雨谷庆王岚哈尔滨工程大学机电工程学院黑龙江哈尔滨150001

当机器人构型不满足Pieper准则的时候,传统的运动学建模方法通常无法求出机器人逆运动学解析解.针对不满足Pieper准则的机器人构型,基于相邻关节轴换位前后正运动学结果不变的准则,提出一种全新的运动学建模方法——相邻关节轴建立顺序... 详细信息

当机器人构型不满足Pieper准则的时候,传统的运动学建模方法通常无法求出机器人逆运动学解析解.针对不满足Pieper准则的机器人构型,基于相邻关节轴换位前后正运动学结果不变的准则,提出一种全新的运动学建模方法——相邻关节轴建立顺序换位法,并给出了适用该方法的机器人构型条件.以一种不满足Pieper准则的微创腹腔手术机器人为例,应用该方法求解出其精确的解析解,并通过Matlab Simulink仿真验证了该方法的正确性.

关键词： Pieper准则解析解逆运动学运动学建模