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光固化3D打印钇铝石榴石透明陶瓷及其微结构调控

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硅酸盐学报 2024年第3期52卷 882-889页

作者：胡松唐雨馨周国红王士维中国科学院上海硅酸盐研究所高性能陶瓷和超微结构国家重点实验室上海201899 中国科学院大学材料科学与光电技术学院北京100049 中国科学院大学北京100049

成型是钇铝石榴石(YAG)透明陶瓷研制的关键环节,对透明陶瓷的致密化过程及其力学、热学和光学性能有重要影响。本工作围绕YAG透明陶瓷的基于数字光处理(DLP)技术的光固化3D打印成型,系统地开展了YAG陶瓷浆料的研制、陶瓷生坯的构筑及坯... 详细信息

成型是钇铝石榴石(YAG)透明陶瓷研制的关键环节,对透明陶瓷的致密化过程及其力学、热学和光学性能有重要影响。本工作围绕YAG透明陶瓷的基于数字光处理(DLP)技术的光固化3D打印成型,系统地开展了YAG陶瓷浆料的研制、陶瓷生坯的构筑及坯体脱脂和烧结工艺研究。采用流变仪分析了固含量对陶瓷浆料流变特性的影响,借助分析曝光参数对单层陶瓷膜特性的影响,确立了最佳的光固化工艺参数。结合TG–DTA分析,对陶瓷坯体脱脂制度进行了精准控制。采用真空高温烧结工艺制备得到高致密YAG透明陶瓷,讨论了固含量、烧结温度等工艺参数对YAG透明陶瓷微结构演变及光学质量的影响,基于DLP光固化成型技术成功制备出可见光透过率高达82.9%的高性能YAG透明陶瓷。

关键词： 3D打印钇铝石榴石透明陶瓷微结构调控

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C/C复合材料高熵氧化物涂层抗烧蚀性能

无机材料学报 2024年第1期39卷 61-70,I0001,I0002页

作者：郭凌翔唐颖黄世伟肖博澜夏东浩孙佳西北工业大学超高温结构复合材料国防科技重点实验室纤维增强轻质复合材料陕西省重点实验室西安710072

新一代高超声速飞行器热端部件服役温度不断提高,对表面防护涂层的相稳定性和抗烧蚀性能提出了更高的要求。本工作针对传统过渡金属氧化物ZrO_(2)、HfO_(2)涂层开展高熵化设计,采用高温固相反应结合超音速大气等离子喷涂制备(Hf_(0.125)... 详细信息

新一代高超声速飞行器热端部件服役温度不断提高,对表面防护涂层的相稳定性和抗烧蚀性能提出了更高的要求。本工作针对传统过渡金属氧化物ZrO_(2)、HfO_(2)涂层开展高熵化设计,采用高温固相反应结合超音速大气等离子喷涂制备(Hf_(0.125)Zr_(0.125)Sm_(0.25)Er_(0.25)Y_(0.25))O_(2-δ)(M1R3O)、(Hf_(0.2)Zr_(0.2)Sm_(0.2)Er_(0.2)Y_(0.2))O_(2-δ)(M2R3O)、(Hf_(0.25)Zr_(0.25)-Sm_(0.167)Er_(0.167)Y_(0.167))O_(2-δ)(M3R3O)三种高熵氧化物涂层,探究稀土组元含量对高熵氧化物涂层的相结构演变规律、相稳定性以及抗烧蚀性能的影响。M2R3O涂层和M3R3O涂层呈现优异的相稳定性和抗烧蚀性能,涂层经热流密度为2.38~2.40 MW/m^(2)的氧–乙炔焰烧蚀后仍保持物相结构稳定,未发生固溶体分解或析出稀土组元。其中M2R3O涂层循环烧蚀180 s后的质量烧蚀率与线烧蚀率分别为0.01 mg/s和–1.16μm/s,相比M1R3O涂层(0.09 mg/s、–1.34μm/s)以及M3R3O涂层(0.02 mg/s、–4.51μm/s),分别降低了88.9%、13.4%以及50.0%、74.3%,表现出最优异的抗烧蚀性能。M2R3O涂层的抗烧蚀性能优异归因于其兼具较高的熔点(>2200℃)和较低的热导率((1.07±0.09)W/(m•K)),使其有效防护内部的SiC过渡层以及C/C复合材料免受氧化损伤,避免了界面SiO_(2)相形成所导致的界面开裂。

关键词：高熵陶瓷过渡金属氧化物热喷涂热防护涂层抗烧蚀 C/C复合材料

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临空经济对区域创新的结构性影响研究

区域经济评论 2024年第1期 52-61页

作者：汤凯蔡晓培完世伟郑州大学商学院郑州450001 河南高质量发展研究院郑州450001 河南省社会科学院经济研究所郑州450002

临空经济在引导区域发展模式向创新驱动型转变中发挥着重要作用,以其独特的“技术—制度—产业—空间”属性,通过技术支撑、制度安排、产业延伸、空间极核等新的范式结构,为区域创新发展提供跃升条件。发展临空经济,能提升城市通达度和... 详细信息

临空经济在引导区域发展模式向创新驱动型转变中发挥着重要作用,以其独特的“技术—制度—产业—空间”属性,通过技术支撑、制度安排、产业延伸、空间极核等新的范式结构,为区域创新发展提供跃升条件。发展临空经济,能提升城市通达度和交通枢纽地位,影响城市创新层级;缩小城市间知识密集型服务业的差距,使城市群向创新多中心空间结构演化;为区域创新发展提供集聚与扩散叠加动力、制度创新变迁动力、政府与市场双向互动激活动力、中心极核与外围互补引领协同动力,影响区域创新的动力结构。各级政府应高度重视临空经济区在改革创新、先行先试中的引领作用,完善现代综合交通运输体系,差异化构建跨空间创新协作网络,促进创新要素流动和知识溢出,激发临空经济在区域创新中的功能。

关键词：临空经济区域创新结构性影响

Temperature-dependent optical resonance in a thin-walled tubular oxide microcavity

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Progress in Natural Science:Materials International 2017年第5期27卷 498-502页

作者： Yangfu Fang Xianyun Lin shiwei tang Borui Xu Jiao Wang Yongfeng Mei Department of Materials Science Fudan University Department of Physics Faculty of Science Ningbo University School of Information Science & Engineering Fudan University

This work proposes a temperature-response capability of optical resonance in tubular optical oxide microcavities. The thin wall thickness with a subwavelength scale enables these microcavities to interact with the environment effectively. By optimization of the geometries and materials, the tubular microcavities can be tuned into temperature-inert in vacuum, and the experiments support this design. The experiments prove the idea of utilizing them as temperature-inert microcavities. Contrary wavelength shifts from previous studies were observed, which can be explained with the theoretical model. Furthermore, the theoretical results of the present work suggest that novel rolled-up microtubes could act as an exceptional optical microcavity for the application in temperature response.

关键词： Microcavities Rolled-up Whispering gallery mode(WGM) Temperature-response Mie scattering method

High-efficiency broadband polarization-independent superscatterer using conformal metasurfaces

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Photonics Research 2018年第8期6卷 782-788页

作者： HE-XIU XU shiwei tang CHEN SUN LIANLIN LI HAIWEN LIU XINMI YANG FANG YUAN YUNMING SUN Air and Missile Defense College Air Force Engineering University Department of Physics Faculty of Science Ningbo University School of Electronic Engineering and Computer Sciences Peking University School of Information Engineering East China Jiaotong University School of Electronics and Information Engineering Soochow University Advanced Technique Department Key Laboratory of Aeronautics Computing Technique

Safe detection of an arbitrarily shaped platform is critical for survivability, rescue, or navigation safety in a remote region. Metasurfaces afford great potential due to their strong electromagnetic(EM) wave control. However,studies have mainly focused on the physics and design of metasurfaces on planar plates, which does not satisfy the current requirements of aerodynamics and aesthetics. Herein, we propose a sophisticated strategy to design a metasurface that can wrap over arbitrarily shaped objects with moderate curvature on which optical aberrations are commonly introduced. By designing each meta-atom on the basis of the required position and phase compensation, exact EM wavefronts are restored. For verification, several conformal metasurfaces were designed and numerically studied on metallic cylinders at the microwave spectrum. A proof-of-concept device is fabricated and is experimentally characterized. The results demonstrate the availability of the desirable dual-beam superscatterer with strong backscattering enhancement toward two directions, thus indicating that the distortions induced by an arbitrary platform can be efficiently corrected. Our method affords an efficient alternative for designing highperformance multifunctional optoelectronic devices equipped on a moderately curved platform.

关键词：安全检测电磁波通讯技术发展现状

二维斑点追踪成像技术在甲型流感相关心肌炎患儿左室功能评估中的价值

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临床儿科杂志 2024年第7期42卷 648-653页

作者：陈晔朱善良杨世伟陈俊花立春唐颖南京医科大学附属儿童医院超声诊断科江苏南京210000 南京医科大学附属儿童医院心内科江苏南京210000

目的探讨二维斑点追踪成像技术在评估甲型流感相关心肌炎患儿左室功能和室壁运动障碍中的价值。方法选取30例甲流相关心肌炎患儿作为病例组,门诊正常体检患儿33例作为正常对照组,对其进行常规超声检查,并运用二维斑点追踪技术评价心功... 详细信息

目的探讨二维斑点追踪成像技术在评估甲型流感相关心肌炎患儿左室功能和室壁运动障碍中的价值。方法选取30例甲流相关心肌炎患儿作为病例组,门诊正常体检患儿33例作为正常对照组,对其进行常规超声检查,并运用二维斑点追踪技术评价心功能及左室整体纵向应变,进行对比分析。结果30例心肌炎患儿年龄、体表面积、左心室舒张末期内径(LVIDd)、舒张末期室间隔厚度(IVSd)、舒张早期与舒张晚期二尖瓣血流速度比值(E/A)、CK-MB指标与正常对照组差异无统计学意义(P>0.05),病例组心率、血hsTnI指标高于对照组,左室射血分数LVEF、舒张早期二尖瓣环运动速度的比值(E/E’)以及左室整体收缩期应变峰值(GLPS)均低于对照组,差异有统计学意义(P<0.05)。GLPS与LVEF呈显著的正相关,与IVSd呈显著的负相关,但与LVIDd、E/A、E/E’以及血hsTnI、CK-MB及心电指标相关性不明显。GLPS诊断小儿甲流相关心肌炎的最佳阈值为-19.9%。结论2 D-STE的左室长轴应变可较准确反映甲流病毒感染所致的心肌炎患儿的左室功能变化,可作为甲流相关心肌炎的早期诊断、随访及预后评估的一种简便安全、可靠的实用新手段。

关键词：甲型流感病毒心肌炎二维斑点追踪技术儿童

饱水裂隙砂岩动态力学特性与裂纹扩展规律研究

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岩石力学与工程学报 2024年第S1期43卷 3131-3139页

作者：平琦孙施佳高祺吴世伟李向阳徐一杰胡静唐庆林安徽理工大学深部煤矿采动响应与灾害防控国家重点实验室安徽淮南232001 安徽理工大学矿山地下工程教育部工程研究中心安徽淮南232001 安徽理工大学土木建筑学院安徽淮南232001

为研究饱水裂隙岩石动态力学特性及裂纹扩展规律,对预制0°,15°,30°,45°,60°,75°,90°共7种倾角裂隙的砂岩试件进行饱水处理,利用SHPB试验装置开展冲击压缩试验。结果表明:不同倾角预制裂隙的饱水砂岩和天然砂岩试件动应力-应变曲... 详细信息

为研究饱水裂隙岩石动态力学特性及裂纹扩展规律,对预制0°,15°,30°,45°,60°,75°,90°共7种倾角裂隙的砂岩试件进行饱水处理,利用SHPB试验装置开展冲击压缩试验。结果表明:不同倾角预制裂隙的饱水砂岩和天然砂岩试件动应力-应变曲线相似,大致分为3个阶段,试件动抗压强度、动应变和动弹性模量均随裂隙倾角增大整体呈先减小后增大的趋势;与预制裂隙天然砂岩试件相比,饱水砂岩试件动抗压强度和动弹性模量略有提升,而动应变减小,表现出动态加载条件下水作用的Stefan效应。随预制裂隙倾角变化,饱水砂岩试件破坏方式呈现为张拉、剪切和张拉剪切复合型等破坏模式,裂隙倾角0°和15°时为Ⅱ型破坏,30°~75°时为Ⅰ-Ⅱ复合型破坏,90°时为Ⅰ型破坏。预制裂隙砂岩试件裂纹起裂位置主要集中在裂隙尖端附近,起裂角随预制裂隙倾角增大而减小,且入射端起裂角大于透射端。

关键词：岩石力学饱水状态裂隙砂岩冲击压缩 SHPB试验装置

Effects of nanoparticle structural features on the light-matter interactions in nanocermet layers and cermet-based solar absorbers

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Journal of Materiomics 2021年第5期7卷 1103-1111页

作者： Xiaoyu Wang Houjin He Junhua Gao Haibo Hu shiwei tang Xiaoyun Li Xiuhong Li Hongtao Cao Ningbo Institute of Materials Technology&Engineering Chinese Academy of SciencesNingbo 315201China School of Physical Science and Technology Ningbo UniversityNingbo 315211China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China

Metallic nanoparticle(NP)/ceramic composite cermets present desirable broadband absorption of the solar spectrum and thus are the preferred material scheme for constructing cermet-based solar absorbers.However,the effects of fine nanoparticle structural features on the light-matter interactions in nanocermet layers and corresponding cermet-based solar absorbers are still not well clear until now.Herein,we report a systematical investigation on the effects of W(tungsten)nanoparticle sizes,its concentrations and configurations in an alumina matrix on the optical responses of WeAl_(2)O_(3) nanocermet layers and a solar absorber with double-cermet layers.It is found that to possess admirable light absorption features at high temperatures,it is better to maintain the fine particle size of less than 10 nm,isolated states and suitable separations between them for WeAl_(2)O_(3) nanocermets.Thus,the dominated intrinsic absorption of W NPs,their plasmonic excitation and coupling effects among each other all contribute significantly to the broadband optical performance of the cermet layers and the whole absorber.More importantly,this study demonstrates a valuable criterion for maintaining optical performances of nanocermet layers and cermet-based solar absorbers under heating and thus their thermal robustness.

关键词： Nanocermet Solar absorbers Tungsten Plasmonic interaction Thermal stability

Ultrawideband chromatic aberration-free meta-mirrors

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Advanced Photonics 2021年第1期3卷 47-56页

作者： Tong Cai shiwei tang Bin Zheng Guangming Wang Wenye Ji Chao Qian Zuojia Wang Erping Li Hongsheng Chena Zhejiang University College of Information Science and Electronic EngineeringInterdisciplinary Center for Quantum InformationState Key Laboratory of Modern Optical InstrumentationHangzhouChina Air Force Engineering University Air and Missile Defend CollegeXi’anChina Zhejiang University ZJU-Hangzhou Global Science and Technology Innovation CenterKey Laboratory of Advanced Micro/Nano Electronic Devices and Smart Systems of ZhejiangHangzhouChina Ningbo University Department of PhysicsFaculty of ScienceNingboChina

Chromatic aberration-free meta-devices(e.g.,achromatic meta-devices and abnormal chromatic meta-devices)play an essential role in modern science and technology.However,current efforts suffer the issues of low efficiency,narrow operating band,and limited wavefront manipulation capability.We propose a general strategy to design chromatic aberration-free meta-devices with high-efficiency and ultrabroadband properties,which is realized by satisfying the key criteria of desirable phase dispersion and high reflection amplitudes at the target frequency interval.The phase dispersion is tuned successfully based on a multiresonant Lorentz model,and high reflection is guaranteed by the presence of the metallic ground.As proof of the concept,two microwave meta-devices are designed,fabricated,and experimentally characterized.An achromatic meta-mirror is proposed within 8 to 12 GHz,and another abnormal chromatic meta-mirror can tune the reflection angle as a linear function.Both meta-mirrors exhibit very high efficiencies(85%to 94%in the frequency band).Our findings open a door to realize chromatic aberration-free meta-devices with high efficiency and wideband properties and stimulate the realizations of chromatic aberration-free metadevices with other functionalities or working at higher frequency.

关键词： chromatic aberration-free meta-devices ultrabroadband metasurface phase and dispersion control multiresonant Lorentz model