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基于双羊角钉型等离子宽带带阻滤波器研究

光电子·激光 2025年第1期36卷 1-8页

作者：王叶壮沈宏君陈俊坤宁夏大学物理学院

为了获得拥有滤波功能的带阻滤波器，并实现宽带滤波，本研究设计了一种金属-绝缘体-金属(metal-insulator-metal, MIM)混合等离子体波导，其结构由双羊角钉谐振腔与MIM直波导组成。本文采用时域有限差分法(finite difference time doma... 详细信息

为了获得拥有滤波功能的带阻滤波器，并实现宽带滤波，本研究设计了一种金属-绝缘体-金属(metal-insulator-metal, MIM)混合等离子体波导，其结构由双羊角钉谐振腔与MIM直波导组成。本文采用时域有限差分法(finite difference time domain, FDTD)计算了此结构的传输光谱特性和z方向磁场分布图，计算结果表明在两个法诺共振峰之间形成了有带阻滤波特性的U字型区域，其滤波的带阻宽度可达0.99μm,实现了宽带滤波功能。基于结构的可协调性，调节双羊角钉谐振腔之间的距离L、高度H以及半径R可以改变共振波长和带阻波段。此外，在添加新的羊角钉谐振腔并形成级联结构后，可以获得新的法诺共振峰，并提高了带阻滤波特性，本研究得到的结构特性可以为带阻滤波器与传感器等光学器件的设计提供思路。

关键词：等离子体波导双羊角钉型谐振腔法诺共振宽带滤波

SUBSTRATE MATERIALS FOR POLY-CSiTF SOLAR CELLS: OPTIMIzATION OF SILICON SHEET FROM POWDER

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 184-188页

作者： Q.Ban H.shen X.J.Wang X.W.zou z.C.Liang StateKeyLaboratoryofOptoelectronicMaterialsandTechnologies DepartmentofPhysicsandEngineeringZhongshan（SunYat-sen）UniversityGuangzhou510275China GuangzhouInstituteofEnergyConversion TheChineseAcademyofSciencesGuangzhou510275China

The optimization of silicon sheet from powder (SSP) technology as polycrystalli ne silicon thin film (poly-CSiTF) solar cells' substrate materials is studied by orthogonal design experimental method. Based on technological optimization of S SP prepared from electronic grade silicon powder, SSP solar cell devices with si mple structure are prepared and the effect of SSP substrate is discussed. Up to now, the conversion efficiency of the prepared solar cells on low purity SSP sub strate with fundamental structure has reached 8.25% (with area of 1cm×1cm).

关键词： poly-CSiTF SSP substrate material

Self-induced birefringence of white-light continuum generated by interaction of focused femtosecond laser pulses with fused silica

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High Power Laser Science and Engineering 2020年第2期8卷 71-76页

作者： J.Qian G.D.Wang K.Y.Lou D.Y.shen Q.Fu Q.z.zhao State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

White-light continuum can be induced by the interaction of intense femtosecond laser pulses with condensed *** using two orthogonal polarizers,a self-induced birefringence of continuum is observed when focusing femtosecond laser pulses into bulk fused *** is,the generated white-light continuum is synchronously modulated anisotropically while propagating in fused ***-resolved detection confirms that self-induced birefringence of continuum shows a growth and saturation feature with time *** adjusting laser energy,the transmitted intensity of continuum modulated by self-induced birefringence also varies *** analysis with time evolution indicates that it is the focused femtosecond laser pulses that induce anisotropic microstructures in bulk fused silica,and the anisotropic structures at the same time modulate the generated continuum.

关键词： femtosecond laser pulses fused silica self-induced birefringence white-light continuum

RHEOLOGY FEATURE OF SIMPLE METAL MELT

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Acta Metallurgica Sinica(English Letters) 2007年第3期20卷 181-186页

作者： C.J. Sun H.R. Geng Y.S. shen X.Y. Teng z.X. Yang Key Laboratory of Liquid Structure and Heredity of Materials Ministry of Education Shandong University Jinan 250061 China School of Material Science and Engineering Jinan University Jinan 250022 China

The rheology feature of Sb, Bi melt and alloys was studied using coaxial cylinder high-temperature viscometer. The results showed that the curve of torsion-rotational speed for Sb melt presents a linear relation in all measured temperature ranges, whereas for the Bi melt, the curve presents obvious non-Newtonian feature within the low temperature range and at relative high shear stress. The rheology feature of Sb80Bi20 and Sb20Bi80 alloy melts was well correlated with that of Sb and Bi, respectively. It is considered that the rheology behavior of Sb melt plays a crucial role in Sb80Bi20 alloy and that of Bi melt plays a crucial role in Sb20Bi80 alloy.

关键词： Newtonian liquid rheology melt Bi Sb

Location-and Relation-Based Clustering on Privacy-Preserving Social Networks

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Tsinghua Science and Technology 2018年第4期23卷 453-462页

作者： Dan Yin Yiran shen College of Computer Science and Technology Harbin Engineering University

Graph clustering has a long-standing problem in that it is difficult to identify all the groups of vertices that are cohesively connected along their internal edges but only sparsely connected along their external edges. Apart from structural information in social networks, the quality of the location-information clustering has been improved by identifying clusters in the graph that are closely connected and spatially compact. However, in real-world scenarios, the location information of some users may be unavailable for privacy reasons, which renders existing solutions ineffective. In this paper, we investigate the clustering problem of privacy-preserving social networks, and propose an algorithm that uses a prediction-and-clustering approach. First, the location of each invisible user is predicted with a probability distribution. Then, each user is iteratively assigned to different clusters. The experimental results verify the effectiveness and efficiency of our method, and our proposed algorithm exhibits high scalability on large social networks.

关键词： clustering location prediction privacy-preserving social networks

Low-Cycle Fatigue Properties of Nickel-Based Superalloys Processed by High-Gradient Directional Solidification

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Acta Metallurgica Sinica(English Letters) 2017年第9期30卷 878-886页

作者： z.D.Fan D.Wang C.Liu G.zhang J.shen L.H.Lou J.zhang Superalloys Division Institute of Metal ResearchChineseAcademy of SciencesShenyang 110016China shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Xi'an Thermal Power Research Institute Co. Ltd.Xi'an 710054China

The low-cycle fatigue （LCF） properties of DD10 （single-crystal） and Dz53 （columnar-grained） superalloys solidified by liquid-metal cooling （LMC） and high-rate solidification （HRS） processes have been systematically investi- gated. It was found that the LCF life of Dz53 solidified by LMC was obviously better than that solidified by HRS. In contrast, for DD10, LMC showed no remarkable influences on LCF properties at high temperature and only improved LCF properties at intermediate temperature. Microstructure examination showed that the cracks generally initiated at microp- ores in the subsurface at intermediate temperature. However, the cracks occurred on the surface due to oxidation, or persistent slip bands near script-MC at high temperature. Therefore, the benefits of LMC technique can be attributed to both of the reduced casting defects which significantly affect the LCF properties at intermediate temperature and the improved microstructural homogeneity which was strongly correlated to the LCF properties of alloys at high temperature.

关键词： Superalloys Rapid solidification Low-cycle fatigue Microstructure

ANTIMONY GRAIN BOUNDARY SEGREGATION AND ITS SUPPRESSION BY CERIUM IN Fe-2%Mn-Sb STRUCTURAL STEELS

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Acta Metallurgica Sinica(English Letters) 2003年第3期16卷 175-182页

作者： z.X.Yuan A.M.Guo J.Liu D.D.shen J.Jia S.H.Song School of Materials and Metallurgy Wuhan University of Science and Technology Wuhan 430081 China Research Institute of Wuhan Iron and Steel Company Wuhan 430080 China Materials Group Department of Mechanical EngineeringBrunel Uliversity Uxbridge Middlesex UBS 3PHUK

Antimony grain boundary segregation in Fe-2%Mn-Sb structure steels has been studied through measurements of the ductile-brittle transition temperature in conjunction with scanning electron microscopy, Auger electron spectroscopy and secondary ion mass spectroscopy. The research result reveals that during tempering or ageing after quenching at 980℃, Sb segregates to grain boundaries with both equilibrium and non-equilibrium natures and brings about temper embrittlement in the steels. Cerium can relieve temper embrittlement of the steels and its segregation to grain boundaries may play an important role in reducing this embrittlement.

关键词： segregation grain boundary rare-earth embrittlement

Rees-Shishikura's Theorem for Geometrically Finite Rational Maps

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Acta Mathematica Sinica,English Series 2017年第12期33卷 1587-1596页

作者： Wen Qiang shen Department of Mathematical Sciences Tsinghua University Beijing 100084 P. R. China

In this paper, we generalize Rees-Shishikura＇s theorem to the class of geometrically finite rational maps.

关键词： Geometrically finite rational map Rees-Shishikura's theorem homeomorphism

Preparation,crystallization,and wetting of znO-Al_2O_3-B_2O_3-SiO_2 glass-ceramics for sealing to Kovar

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International Journal of Minerals,Metallurgy and Materials 2009年第5期16卷 586-591页

作者： Mao Wu Xin-bo He zhuo-shen shen Xuan-hui Qu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

A novel type of znO-Al2O3-B2O3-SiO2 glass-ceramics sealing to Kovar in electronic packaging was developed, whose thermal expansion coefficient and electrical resistance are 5.2× 10^-6/℃ and over 1×10^13 Ω·cm, respectively. The major crystalline phases in the glass-ceramic seals were znAl2O4, znB2O4, and NaSiAl2O4. The dielectric resistance of the glass-ceramic could be remarkably enhanced through the control of alkali metal ions into crystal lattices. It was found that crystallization happened first on the surface of the sample, leaving the amorphous phase in the inner, which made the glass suitable for sealing. The glass-ceramic showed better wetting on the Kovar surface, and sealing atmosphere and temperature had great effect on the wetting angle. Strong interracial bonding was obtained, which was mainly attributed to the interracial reaction between SiO2 and FeO or Fe3O4.

关键词： electronic packaging materials glass-ceramic crystallization wetting sealing