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人体手舟骨显微形态学特征的Micro CT成像技术分析
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作者 张德洲 吕远 +12 位作者 李琨 陈杰 杨向荣 赵海龙 张少杰 马渊 郝韵腾 杨洋 高明杰 王志强 李志军 史君 王星 《中国组织工程研究》 北大核心 2026年第21期5573-5581,共9页
背景:临床上,由于手舟骨的特殊解剖特点和内部骨小梁分布特征等往往使得骨折的治疗效果普遍不佳,常导致骨折不愈合和缺血性坏死,进而引发腕关节炎和功能丧失。目的:利用Micro CT技术对手舟骨标本进行扫描,分析其内部显微结构特征,测量... 背景:临床上,由于手舟骨的特殊解剖特点和内部骨小梁分布特征等往往使得骨折的治疗效果普遍不佳,常导致骨折不愈合和缺血性坏死,进而引发腕关节炎和功能丧失。目的:利用Micro CT技术对手舟骨标本进行扫描,分析其内部显微结构特征,测量各区域骨小梁显微结构参数值,以发现手舟骨骨小梁的区域差异,旨在为手舟骨骨折的预防、治疗及骨折机制研究提供科学依据。方法:选取5具成人尸体标本的双侧手舟骨(10例)进行Micro CT扫描,通过对手舟骨3个感兴趣区域(结节部、腰部、体部)内骨小梁的勾选与重建,详细观察手舟骨内部的显微形态特征,测量和比较各区域骨小梁显微结构参数值的差异。结果与结论:①Micro CT图像显示手舟骨表面皮质骨相对较薄,内部充满复杂的骨小梁微观结构;靠近皮质骨的板层状骨小梁相对密集,向内部延伸成杆状骨小梁;从矢状面、冠状面和横断面上观察,腰部内骨小梁分布较为稀疏,而体部和结节部内骨小梁分布则更为致密;②手舟骨结节部的骨体积分数、骨表面积、骨表面积组织体积比、骨小梁分离度、骨小梁数目、骨小梁连通性、骨小梁连接密度、分形维数、骨矿物质密度和骨矿物质含量在左右侧别间比较差异均有显著性意义(P<0.05);腰部和体部的各骨小梁显微结构参数值在左右侧别间比较差异均无显著性意义(P>0.05);③手舟骨的骨体积、骨体积分数、骨表面积、骨表面积组织体积比、骨表面积骨体积比、骨矿物质密度和骨矿物质含量在体部与结节部、腰部之间比较差异有显著性意义(P<0.05);手舟骨的骨小梁厚度在体部与结节部之间比较差异有显著性意义(P<0.05);手舟骨的骨小梁分离度、分形维数在体部与结节部、腰部,结节部与腰部之间差异有显著性意义(P<0.05);手舟骨的骨小梁数目、骨小梁连通性、骨小梁连接密度在腰部与结节部、体部之间比较差异有显著性意义(P<0.05);手舟骨的组织体积、各向异性程度在体部、结节部、腰部之间比较差异均无显著性意义(P>0.05);④结果显示,手舟骨的骨小梁显微结构参数值存在区域性差异,其中腰部的骨密度和强度较低,是最容易发生骨折的部位,该发现从骨小梁微观结构角度为理解手舟骨骨折机制提供了理论依据;同时,此次研究揭示的手舟骨不同部位的骨小梁结构特征也为设计针对性的内固定器械提供了理论依据。 展开更多
关键词 手舟骨 Micro CT 显微形态 骨小梁 区域差异 骨小梁显微结构
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High-throughput structure determination of polycrystalline functional materials:a platform for automated 3DED/MicroED data collection
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作者 Zhenghan Zhang Zhengyin Liang +2 位作者 Chao Ma Cong Lin Jian Li 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第12期4158-4166,共9页
Structure determination plays the most crucial role in the discovery of novel functional materials,because only by knowing the intrinsic structures can we accurately and completely understand their properties and appl... Structure determination plays the most crucial role in the discovery of novel functional materials,because only by knowing the intrinsic structures can we accurately and completely understand their properties and applications.However,most new materials are obtained in polycrystalline form or even as mixtures with multiple phases when first synthesized,presenting significant challenges in their structure determination and phase elucidation.Fortunately,the developed three-dimensional electron diffraction(3DED/MicroED)has provided a promising solution to overcome these challenges.In this study,we have constructed a state-of-the-art 3DED/MicroED data acquisition equipment by integrating a hybrid-pixel detector with a script developed for Serial EM,and thus successfully developed an automated 3DED/MicroED method for the high-throughput structure determination.To demonstrate its effectiveness,a multiphase sample with complex porous structures is employed,showcasing that individual phases and their structures can be identified and determined,respectively.One remarkable finding is the identification of an impurity metal-organic framework(MOF)that is completely invisible to traditional powder X-ray diffraction in a supposedly“pure”commercial MOF sample.Additionally,our method also enables the atomic-resolution structure determination of flexible covalent organic framework materials,which are highly sensitive to electron beams.Moreover,a new microporous aluminoborate is discovered using this rapid structure determination method.These experimental results highlight the enormous potential of our 3DED/MicroED method in the field of new materials discovery,offering a powerful tool for the structure determination of polycrystalline functional materials. 展开更多
关键词 3DED/microed high-throughput structure determination mixed phase porous materials
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MicroED as a powerful technique for the structure determination of complex porous materials
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作者 Chao Ma Cong Lin Jian Li 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2024年第3期41-54,共14页
Porous materials have garnered significant attention in recent years.Understanding the intrinsic relationship between their structures and properties requires precise knowledge of their atomic structures.Single-crysta... Porous materials have garnered significant attention in recent years.Understanding the intrinsic relationship between their structures and properties requires precise knowledge of their atomic structures.Single-crystal X-ray diffraction(SCXRD)has traditionally been the primary method for elucidating such structures,but it demands large,high-quality crystals,often exceeding 5μm in size.The growth of these crystals can be a time-consuming process,especially for one-and two-dimensional materials.To explore structures at the nanoscale,MicroED(microcrystal electron diffraction(ED))offers unprecedented insights into the realm of nanomaterials.This revolutionary technique enables researchers to uncover intricate details within nanoscale structures,promising to reshape our fundamental understanding of materials.In this review,we delve into the applications of MicroED in the study of various porous materials,including zeolites,metal-organic frameworks(MOFs),and covalent organic frameworks(COFs).We emphasize the pivotal role of MicroED in nanomaterial characterization,enabling precise crystallographic analysis and phase identification. 展开更多
关键词 Atomic structure microed Porous materials Three-dimensional electron diffraction
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Tunable Optical Metamaterial Enables Steganography,Rewriting,and Multilevel Information Storage
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作者 Jianchen Zheng Yuzhao Zhang +7 位作者 Haibo Yu Jingang Wang Hongji Guo Ye Qiu Xiaoduo Wang Yu Feng Lianqing Liu Wen Jung Li 《Nano-Micro Letters》 2026年第2期553-568,共16页
In the realm of secure information storage,optical encryption has emerged as a vital technique,particularly with the miniaturization of encryption devices.However,many existing systems lack the necessary reconfigurabi... In the realm of secure information storage,optical encryption has emerged as a vital technique,particularly with the miniaturization of encryption devices.However,many existing systems lack the necessary reconfigurability and dynamic functionality.This study presents a novel approach through the development of dynamic optical-to-chemical energy conversion metamaterials,which enable enhanced steganography and multilevel information storage.We introduce a micro-dynamic multiple encryption device that leverages programmable optical properties in coumarin-based metamaterials,achieved through a direct laser writing grayscale gradient strategy.This methodology allows for the dynamic regulation of photoluminescent characteristics and cross-linking networks,facilitating innovative steganographic techniques under varying light conditions.The integration of a multi-optical field control system enables real-time adjustments to the material’s properties,enhancing the device’s reconfigurability and storage capabilities.Our findings underscore the potential of these metamaterials in advancing the field of microscale optical encryption,paving the way for future applications in dynamic storage and information security. 展开更多
关键词 Micro/nano-device Optical encryption METAMATERIALS Photoluminescence 4D printing
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Superelastic and Washable Micro/Nanofibrous Sponges Based on Biomimetic Helical Fibers for Efficient Thermal Insulation
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作者 Fengjin Yang Zhifei Wang +7 位作者 Wei Zhang Sai Wang Yi‑Tao Liu Fei Wang Roman ASurmenev Jianyong Yu Shichao Zhang Bin Ding 《Nano-Micro Letters》 2026年第2期170-182,共13页
Extreme cold weather seriously harms human thermoregulatory system,necessitating high-performance insulating garments to maintain body temperature.However,as the core insulating layer,advanced fibrous materials always... Extreme cold weather seriously harms human thermoregulatory system,necessitating high-performance insulating garments to maintain body temperature.However,as the core insulating layer,advanced fibrous materials always struggle to balance mechanical properties and thermal insulation,resulting in their inability to meet the demands for both washing resistance and personal protection.Herein,inspired by the natural spring-like structures of cucumber tendrils,a superelastic and washable micro/nanofibrous sponge(MNFS)based on biomimetic helical fibers is directly prepared utilizing multiple-jet electrospinning technology for high-performance thermal insulation.By regulating the conductivity of polyvinylidene fluoride solution,multiple-jet ejection and multiple-stage whipping of jets are achieved,and further control of phase separation rates enables the rapid solidification of jets to form spring-like helical fibers,which are directly entangled to assemble MNFS.The resulting MNFS exhibits superelasticity that can withstand large tensile strain(200%),1000 cyclic tensile or compression deformations,and retain good resilience even in liquid nitrogen(-196℃).Furthermore,the MNFS shows efficient thermal insulation with low thermal conductivity(24.85 mW m^(-1)K^(-1)),close to the value of dry air,and remains structural stability even after cyclic washing.This work offers new possibilities for advanced fibrous sponges in transportation,environmental,and energy applications. 展开更多
关键词 ELECTROSPINNING Micro/nanofibrous sponge Hierarchical structure SUPERELASTICITY Thermal insulation
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Joule heating activation-assisted full-depth doping enabling fast-kinetic and stable micro silicon anodes in solid-state batteries
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作者 Xin Qin Zuqiang Ge +7 位作者 Yafei Wang Guanzhong Ma Fei Yang Qian Xu Yanpeng Li Debin Kong Junwei Han Linjie Zhi 《Journal of Energy Chemistry》 2026年第1期208-218,I0006,共12页
Micro silicon(mSi)is a promising anode candidate for all-solid-state batteries due to its high specific capacity,low side reactions,and high tap density.However,silicon suffers from its poor electronic and ionic condu... Micro silicon(mSi)is a promising anode candidate for all-solid-state batteries due to its high specific capacity,low side reactions,and high tap density.However,silicon suffers from its poor electronic and ionic conductivity,which is particularly severe on a micro scale and in solid-state systems,leading to increased polarization and inferior electrochemical performance.Doping can broaden the transmission pathways and reduce the diffusion energy barrier for electrons and lithium ions.However,achieving effective,uniform doping in mSi is challenging due to its longer diffusion paths and higher energy barriers.Therefore,current doping research is primarily limited to nanosilicon.In this study,we successfully used a Joule-heating activated staged thermal treatment to achieve full-depth doping of germanium(Ge)in the mSi substrate.The Joule-heating process activated the mSi substrate,resulting in abundant vacancy defects that reduced the diffusion barrier of Ge into the silicon lattice and facilitated full-depth Ge doping.Surprisingly,the resulting Si-Ge anode exhibited significantly enhanced electrical conductivity(70 times).Meanwhile,the improved Li-ion conductivity in mSi and the reduced Young’s modulus enhance the electrode reaction kinetics and integrity after cycling.Ge-doped silicon anodes demonstrate excellent electrochemical performance when applied in sulfide solid-state half-cells and full-cells.This work provides substantial insights into the rational structural design of mSi alloyed anode materials,paving the way for the development of high-performance solid-state Li-ion batteries. 展开更多
关键词 Micro silicon Solid-state batteries Full-depth doping Sulfide solid-state electrolytes
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Micro/Nano‑Reconfigurable Robots for Intelligent Carbon Management in Confined‑Space Life‑Support Systems
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作者 Wei Lu Rimei Chen +5 位作者 Lianlong Zhan Qin Xiang Renting Huang Lei Wang Shuangfei Wang Hui He 《Nano-Micro Letters》 2026年第3期210-226,共17页
Strategically coupling nanoparticle hybrids and internal thermosensitive molecular switches establishes an innovative paradigm for constructing micro/nanoscale-reconfigurable robots,facilitating energyefficient CO_(2)... Strategically coupling nanoparticle hybrids and internal thermosensitive molecular switches establishes an innovative paradigm for constructing micro/nanoscale-reconfigurable robots,facilitating energyefficient CO_(2) management in life-support systems of confined space.Here,a micro/nano-reconfigurable robot is constructed from the CO_(2) molecular hunters,temperature-sensitive molecular switch,solar photothermal conversion,and magnetically-driven function engines.The molecular hunters within the molecular extension state can capture 6.19 mmol g^(−1) of CO_(2) to form carbamic acid and ammonium bicarbonate.Interestingly,the molecular switch of the robot activates a molecular curling state that facilitates CO_(2) release through nano-reconfiguration,which is mediated by the temperature-sensitive curling of Pluronic F127 molecular chains during the photothermal desorption.Nano-reconfiguration of robot alters the amino microenvironment,including increasing surface electrostatic potential of the amino group and decreasing overall lowest unoccupied molecular orbital energy level.This weakened the nucleophilic attack ability of the amino group toward the adsorption product derivatives,thereby inhibiting the side reactions that generate hard-to-decompose urea structures,achieving the lowest regeneration temperature of 55℃ reported to date.The engine of the robot possesses non-contact magnetically-driven micro-reconfiguration capability to achieve efficient photothermal regeneration while avoiding local overheating.Notably,the robot successfully prolonged the survival time of mice in the sealed container by up to 54.61%,effectively addressing the issue of carbon suffocation in confined spaces.This work significantly enhances life-support systems for deep-space exploration,while stimulating innovations in sustainable carbon management technologies for terrestrial extreme environments. 展开更多
关键词 Micro/nano RECONFIGURABLE Robot Confined space CO_(2)management Efficient regeneration
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Correction: Optimizing Exciton and Charge-Carrier Behavior in Thick-Film Organic Photovoltaics: A Comprehensive Review
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作者 Lu Wei Yaxin Yang +2 位作者 Lingling Zhan Shouchun Yin Hongzheng Chen 《Nano-Micro Letters》 2026年第1期608-608,共1页
Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.Th... Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.The published version showed“Hongzhen Chen”,whereas the correct spelling should be“Hongzheng Chen”.The correct author name has been provided in this Correction,and the original article[1]has been corrected. 展开更多
关键词 charge carrier behavior exciton behavior comprehensive review thick film organic photovoltaics nano micro letters
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Improving the interfacial strength of cement-polyacrylate grout and Ordovician limestone by graphene oxide
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作者 Zhiyang Wang Yingwei Li +3 位作者 Longji Wu He Chen Xiuliang Yin Zhijun Wu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期702-712,共11页
In coal mining on a high-pressure Ordovician limestone aquifer,grouting materials should have sufficient mechanical properties,particularly strong interfacial bonding performance to address stress concentration at the... In coal mining on a high-pressure Ordovician limestone aquifer,grouting materials should have sufficient mechanical properties,particularly strong interfacial bonding performance to address stress concentration at the grout-limestone interface induced by rock stress disturbances during mining.In this study,graphene oxide(GO)was integrated into cement-polyacrylate composite grout to improve its interfacial bonding.First,four-point bending tests were conducted,and the Monte Carlo method combined with the simplex search algorithm was employed to determine the variations in shear cohesion and static friction parameters.The results reveal that GO can significantly increase both the tensile and shear cohesion of the grout-limestone interface,but minimally affects the interfacial friction coefficient.Second,nuclear magnetic resonance(NMR)and scanning electron microscopy(SEM)tests were performed.The results indicate that GO nanosheets result in a squamaceous microstructure of the grout consolidation mass,increasing the adhesion of the grout-limestone interface.Moreover,spiny Aft(ettringite)clusters can be induced in limestone fracture surfaces by GO,which could serve as anchors for limestone and grout consolidation mass. 展开更多
关键词 Graphene oxide Cement-polyacrylate grout Grout-limestone interfacial strength Spiny cement hydration product crystals Micro anchoring
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CO_(2)nanobubble-enhanced cement-fly ash backfill:Optimizing aggregate gradation and microstructure
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作者 Xiaoxiao Cao Haoyan Lyu +4 位作者 Yanlong Chen Jiangyu Wu Hideki Shimada Takashi Sasaoka Akihiro Hamanaka 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期129-140,共12页
Mine filling materials urgently need to improve mechanical properties and achieve low-carbon transformation.This study explores the mechanism of the synergistic effect of optimizing aggregate fractal grading and intro... Mine filling materials urgently need to improve mechanical properties and achieve low-carbon transformation.This study explores the mechanism of the synergistic effect of optimizing aggregate fractal grading and introducing CO_(2)nanobubble technology to improve the performance of cement-fly ash-based backfill materials(CFB).The properties including fluidity,setting time,uniaxial compressive strength,elastic modulus,porosity,microstructure and CO_(2)storage performance were systematically studied through methods such as fluidity evaluation,time test,uniaxial compression test,mercury intrusion porosimetry(MIP),scanning electron microscopy-energy dispersive spectroscopy analysis(SEM-EDS),and thermogravimetric-differential thermogravimetric analysis(TG-DTG).The experimental results show that the density and strength of the material are significantly improved under the synergistic effect of fractal dimension and CO_(2)nanobubbles.When the fractal dimension reaches 2.65,the mass ratio of coarse and fine aggregates reaches the optimal balance,and the structural density is greatly improved at the same time.At this time,the uniaxial compressive strength and elastic modulus reach their peak values,with increases of up to 13.46%and 27.47%,respectively.CO_(2)nanobubbles enhance the material properties by promoting hydration reaction and carbonization.At the microscopic level,CO_(2)nanobubble water promotes the formation of C-S-H(hydrated calcium silicate),C-A-S-H(hydrated calcium aluminium silicate)gel and CaCO_(3),which is the main way to enhance the performance.Thermogravimetric studies have shown that when the fractal dimension is 2.65,the dehydration of hydration products and the decarbonization process of CaCO_(3)are most obvious,and CO_(2)nanobubble water promotes the carbonization reaction,making it surpass the natural state.The CO_(2)sequestration quality of cement-fly ash-based materials treated with CO_(2)nanobubble water at different fractal dimensions increased by 12.4wt%to 99.8wt%.The results not only provide scientific insights for the design and implementation of low-carbon filling materials,but also provide a solid theoretical basis for strengthening green mining practices and promoting sustainable resource utilization. 展开更多
关键词 cement-fly ash-based backfill CO_(2)nanobubble fractal dimension macro and micro performance carbon sequestration
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基于原位动态Micro CT的针刺预制体结构表征及工艺改进
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作者 张文奇 任志鹏 +4 位作者 邹艳玲 耿巍麟 陈伟 王孝锋 蒋云 《棉纺织技术》 2026年第3期42-47,共6页
采用原位动态Micro CT技术对某梯度密度针刺预制体进行无损检测与分析,通过高分辨率扫描和三维重构技术,实现了材料内部三维组织结构的精确表征,并定量统计了针刺纤维束的长度、直径等参数。结果表明:原工艺加工的产品均匀性存在缺陷;... 采用原位动态Micro CT技术对某梯度密度针刺预制体进行无损检测与分析,通过高分辨率扫描和三维重构技术,实现了材料内部三维组织结构的精确表征,并定量统计了针刺纤维束的长度、直径等参数。结果表明:原工艺加工的产品均匀性存在缺陷;结合统计数据,对织物层间及面内针刺工艺参数优化后,针刺纤维束平均直径提升约36%,表明纤维间的结合更加紧密;针刺纤维束长度下降约6%,说明纤维分布更加均匀。认为:通过原位动态Micro CT技术优化针刺工艺,可实现从结构表征到工艺改进的闭环优化,具有重要的工程应用价值。 展开更多
关键词 原位动态Micro CT 预制体 无损检测 三维结构 针刺均匀性 针刺纤维束
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How will the first structural interest rate cut in 2026 empower small and medium-sized textile enterprises to achieve high-quality development?
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作者 Qiu Shuchen 《China Textile》 2026年第1期16-17,共2页
On January 19,2026,China's first structural interest rate cut of the year took effect.The People's Bank of China announced a 0.25 percentage point reduction in relending and rediscount rates,targeting key sect... On January 19,2026,China's first structural interest rate cut of the year took effect.The People's Bank of China announced a 0.25 percentage point reduction in relending and rediscount rates,targeting key sectors like small and micro enterprises(SMEs),technological innovation,and green transition.For the textile industry,where small and medium-sized enterprises account for over 90%of traditional manufacturing,the policy benefits will inject strong momentum into the high-quality development from multiple dimensions,including reduced financing costs,support for transformation funds,and expansion of foreign trade markets. 展开更多
关键词 structural interest rate cut small micro enterprises smes technological foreign trade markets financing costs high quality development textile industry transformation funds small medium sized enterprises
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基于专利视角的Micro LED产业技术态势分析
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作者 胡思思 李贞贞 《世界科技研究与发展》 2025年第5期651-662,共12页
Micro LED作为新一代显示技术,凭借高亮度、高分辨率、低功耗等特性成为全球显示产业竞争焦点。本文基于专利计量与BERTopic模型方法,对全球Micro LED技术开展专利分析,从技术分布、创新主体、技术主题、法律状态、价值分布等多个维度,... Micro LED作为新一代显示技术,凭借高亮度、高分辨率、低功耗等特性成为全球显示产业竞争焦点。本文基于专利计量与BERTopic模型方法,对全球Micro LED技术开展专利分析,从技术分布、创新主体、技术主题、法律状态、价值分布等多个维度,系统梳理了该领域的发展现状与趋势。研究表明:中国的专利申请量占据全球主导地位,但高价值专利仍集中于美国和日本等发达国家;显示设备、量子点/全彩化、显示应用、材料与元器件、芯片及显示屏六大领域是专利技术重点细分方向;巨量转移、全彩显示等关键技术仍处于突破阶段,产业生态需进一步完善;光电子与集成电路、人工智能等电子信息技术的深度融合进一步驱动Micro LED技术向高精度、高集成度方向发展。基于分析结果,本文从核心技术突破、产学研协同机制、差异化应用场景、国际竞争力提升等方面提出建议,为中国Micro LED产业高质量发展提供参考。 展开更多
关键词 Micro LED 专利分析 BERTopic 巨量转移 全彩显示
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Structure elucidation of plumerubradins A-C:Correlations between^(1)H NMR signal patterns and structural information of[2+2]-type cyclobutane derivatives
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作者 Yu Xiong Li-Jun Hu +7 位作者 Jian-Guo Song Di Zhang Yi-Shuang Peng Xiao-Jun Huang Jian Honga Bin Zhu Wen-Cai Ye Ying Wang 《Chinese Chemical Letters》 2025年第5期369-374,共6页
[2+2]-Type cyclobutane derivatives comprise a large family of natural products with diverse molecular architectures.However,the structure elucidation of the cyclobutane ring,including its connection mode and stereoche... [2+2]-Type cyclobutane derivatives comprise a large family of natural products with diverse molecular architectures.However,the structure elucidation of the cyclobutane ring,including its connection mode and stereochemistry,presents a significant challenge.Plumerubradins A-C(1-3),three novel iridoid glycoside[2+2]dimers featuring a highly functionalized cyclobutane core and multiple stereogenic centers,were isolated from the flowers of Plumeria rubra.Through biomimetic semisynthesis and chemical degradation of compounds 1-3,synthesis of phenylpropanoid-derived[2+2]dimers 7-10,combined with extensive spectroscopic analysis,single-crystal X-ray crystallography,and microcrystal electron diffraction experiments,the structures with absolute configurations of 1-3 were unequivocally elucidated.Furthermore,quantum mechanics-based^(1)H NMR iterative full spin analysis successfully established the correlations between the signal patterns of cyclobutane protons and the structural information of the cyclobutane ring in phenylpropanoid-derived[2+2]dimers,providing a diagnostic tool for the rapid structural elucidation of[2+2]-type cyclobutane derivatives. 展开更多
关键词 Plumeria rubra CYCLOBUTANE Biomimetic semisynthesis microed QM-HiFSA Empirical rule for structure elucidation
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Micro LED表面缺陷的快速高精度检测 被引量:3
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作者 赵天元 董登峰 +2 位作者 王国名 王博 周维虎 《光学精密工程》 北大核心 2025年第9期1434-1445,共12页
为了满足Micro LED缺陷检测对实时性和高精度的要求,结合轻量化的设计和增强的特征提取能力,提出了一种快速高精度的检测算法LED-YOLO。该方法通过设计图像采集系统并结合多种数据增广策略,模拟工业环境中的实际干扰,增强了训练数据的... 为了满足Micro LED缺陷检测对实时性和高精度的要求,结合轻量化的设计和增强的特征提取能力,提出了一种快速高精度的检测算法LED-YOLO。该方法通过设计图像采集系统并结合多种数据增广策略,模拟工业环境中的实际干扰,增强了训练数据的多样性。针对Micro LED缺陷的低区分度问题,提出了轻量级动态融合模块(Lightweight Dynamic Fusion Module,LDFM),该模块结合动态卷积、深度卷积和通道混合操作,在保持模型轻量化的同时,提升了特征表达能力。为了进一步加强缺陷区域的关注,设计了增强协调注意力模块(Enhanced Coordinate Attention Module,ECAM),通过结合通道和空间注意力机制及残差连接,增强了特征提取的准确性。最后,考虑到Micro LED图像的纵横比变化较小,引入动态聚焦机制,提出了DIoU_W回归损失函数,显著提高了模型的收敛速度和稳定性。实验结果表明,LED-YOLO的检测准确率、召回率、mAP、F1值均优于目前最先进的YOLOv11s模型,在参数量减少1.6 M的情况下,检测速度和检测精度均有明显提升,可以有效满足实际Micro LED面板制造过程的质量检验需求。 展开更多
关键词 深度学习 Micro LED 缺陷检测 动态卷积 注意力机制
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基于量子点颜色转换层的Micro LED研究进展
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作者 程旭东 陈祖康 +3 位作者 张针霖 朱艳青 徐刚 徐雪青 《新能源进展》 北大核心 2025年第1期107-120,共14页
微发光二极管(Micro LED)显示器是由微米级半导体发光像元阵列所组成的新型显示技术,是显示技术与LED技术复合集成的综合性技术。与液晶显示器和有机发光二极管显示器相比,Micro LED具有对比度高、功耗低、寿命长、响应时间短等优点。然... 微发光二极管(Micro LED)显示器是由微米级半导体发光像元阵列所组成的新型显示技术,是显示技术与LED技术复合集成的综合性技术。与液晶显示器和有机发光二极管显示器相比,Micro LED具有对比度高、功耗低、寿命长、响应时间短等优点。然而,由于LED芯片尺寸缩小至20μm以下,导致其吸收截面减小,使得传统的荧光粉颜色转换技术无法提供足够的亮度和产量,以满足高分辨率显示的需求。而量子点材料凭借其高量子产率、宽色域、颜色可调等优点,有望成为代替荧光粉的最佳材料。结合了量子点颜色转换技术的Micro LED光电器件具有高亮度、高效率和宽色域的优势,在显示领域具有广阔的应用前景。目前许多学界和产业界的研究者对全彩显示的Micro LED进行了深入研究,逐步实现了Micro LED的商业化。简要回顾了广泛应用于显示领域的量子点材料合成和优异性能的重要研究成果,然后以印刷技术、光刻技术、微流控技术、激光写入技术这四种效果突出的颜色转换层沉积工艺分类总结了基于量子点颜色转换技术Micro LED的全彩显示策略与性能优劣。最后,对基于量子点颜色转换层的Micro LED光电器件的应用前景进行了展望。 展开更多
关键词 量子点 Micro LED 颜色转换层 全彩显示
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急性痛风性关节炎小鼠模型^(18)F-NaF micro PET/CT显像的实验研究
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作者 游智骁 朱焓钰 +5 位作者 石野宽 李沛琳 黄晓红 张曾 李素平 游金辉 《生物医学工程学杂志》 北大核心 2025年第6期1251-1256,共6页
本研究旨在探究^(18)F-NaF micro PET/CT显像对急性痛风性关节炎(AGA)小鼠模型的诊断价值。选取雄性Balb/c小鼠正常组(A组)3只,AGA模型组(B组)18只;A组与模型组B组(B_(1h)、B_(3h)、B_(6h)、B_(8h)、B_(12h)、B_(24h))均于注射显像剂40 ... 本研究旨在探究^(18)F-NaF micro PET/CT显像对急性痛风性关节炎(AGA)小鼠模型的诊断价值。选取雄性Balb/c小鼠正常组(A组)3只,AGA模型组(B组)18只;A组与模型组B组(B_(1h)、B_(3h)、B_(6h)、B_(8h)、B_(12h)、B_(24h))均于注射显像剂40 min后进行micro PET/CT显像。各组小鼠均行血常规分析、血尿酸检测和踝关节病理组织活检。本研究结果显示:B组血常规炎性细胞数均高于A组,其中B_(6h)、B_(8h)组与A组差异有统计学意义(P<0.05)。^(18)F-NaF micro PET/CT显像示B组右侧踝关节可见异常显像剂聚集灶,但病灶处CT并未见骨质破坏;A组左侧踝关节均未见明显显像剂异常聚集灶。B组右侧与左侧踝关节最大标准化摄取值(SUVmax)比值(R/LSUVmax)均高于A组,其中B_(6h)组与A组差异有统计学意义(P<0.05)。R/LSUVmax比值与血常规白细胞数、中性粒细胞数及病理组织镜下炎性细胞数呈正相关(分别为R=0.79,P<0.01;R=0.72,P<0.01;R=0.79,P<0.01)。综上,^(18)F-NaF micro PET/CT显像可早期检测AGA骨代谢改变,可实现AGA病理生理动态改变的可视化监测。 展开更多
关键词 micro PET/CT 痛风性关节炎 ^(18)F-NaF 骨关节 尿酸钠 小鼠
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3D printed hybrid rocket fuels with μAl core-shell particles coated with polyvinylidene fluoride and polydopamine: Enhanced combustion characteristics 被引量:2
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作者 Qihang Chen Xiaolong Fu +6 位作者 Weitao Yang Suhang Chen Zhiming Guo Rui Hu Huijie Zhang Lianpeng Cui Xu Xia 《Defence Technology(防务技术)》 2025年第4期59-70,共12页
3D printing technology enhances the combustion characteristics of hybrid rocket fuels by enabling complex geometries. However, improvements in regression rates and energy properties of monotonous 3D printed fuels have... 3D printing technology enhances the combustion characteristics of hybrid rocket fuels by enabling complex geometries. However, improvements in regression rates and energy properties of monotonous 3D printed fuels have been limited. This study explores the impact of poly(vinylidene fluoride) and polydopamine-coated aluminum particles on the thermal and combustion properties of 3D printed hybrid rocket fuels. Physical self-assembly and anti-solvent methods were employed for constructing composite μAl particles. Characterization using SEM, XRD, XPS, FTIR, and μCT revealed a core-shell structure and homogeneous elemental distribution. Thermal analysis showed that PVDF coatings significantly increased the heat of combustion for aluminum particles, with maximum enhancement observed in μAl@PDA@PVDF(denoted as μAl@PF) at 6.20 k J/g. Subsequently, 3D printed fuels with varying pure and composite μAl particle contents were prepared using 3D printing. Combustion tests indicated higher regression rates for Al@PF/Resin composites compared to pure resin, positively correlating with particle content. The fluorocarbon-alumina reaction during the combustion stage intensified Al particle combustion, reducing residue size. A comprehensive model based on experiments provides insights into the combustion process of PDA and PVDF-coated droplets. This study advances the design of 3D-printed hybrid rocket fuels, offering strategies to improve regression rates and energy release, crucial for enhancing solid fuel performance for hybrid propulsion. 展开更多
关键词 Hybrid propulsion Regression rate 3D print fuels Micro aluminum CORE-SHELL mAl@PDA@PVDF
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In situ preparation of nano cone-like structures on 3D printed titanium alloy implants via one-step femtosecond laser manufacturing for better osseointegration,anti-corrosion,and anti-fatigue 被引量:2
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作者 Yazhou Hu Hongshui Wang +5 位作者 Donghui Wang Xiaomei Xia Ning Liu Tai Yang Baoe Li Chunyong Liang 《Journal of Materials Science & Technology》 2025年第3期88-99,共12页
The poor surface conditions and osseointegration capacity of 3D printed Ti6Al4V implants(3DPT)significantly influence their performance as orthopedic and dental implants.In this work,we creatively introduce a one-step... The poor surface conditions and osseointegration capacity of 3D printed Ti6Al4V implants(3DPT)significantly influence their performance as orthopedic and dental implants.In this work,we creatively introduce a one-step femtosecond laser treatment to improve the surface conditions and osteointegration.The surface characterization,mechanical properties,corrosion resistance,and biological responses were investigated.These results found that femtosecond laser eliminated defects like embedded powders and superficial cracks while forming the nano cones-like structures surface on 3DPT,leading to enhanced osseointegration,anti-corrosion,and anti-fatigue performance.Molecular dynamics simulations revealed the ablation removal mechanism and the formation of nano cone-like structures.These findings were further supported by the in vivo studies,showing that the FS-treated implants had superior bone-implant contact and osseointegration.Hence,the one-step femtosecond laser method is regarded as a promising surface modification method for improving the functional performance of Ti-based orthopedic implants. 展开更多
关键词 3D printed Femtosecond laser Surface modification MICRO/NANOSTRUCTURE OSSEOINTEGRATION
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医用PDA常见故障分析与维护 被引量:1
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作者 张建楠 《设备管理与维修》 2025年第2期70-73,共4页
医用PDA是病房中对患者及其治疗过程进行管理不可或缺的设备,使用范围可覆盖全医院各科室病房。针对N1s型医用PDA,分析设备工作原理,提出常见故障分析与维修思路,并结合实际使用场景分析导致PDA损坏的原因,总结易损配件的日常维护及注... 医用PDA是病房中对患者及其治疗过程进行管理不可或缺的设备,使用范围可覆盖全医院各科室病房。针对N1s型医用PDA,分析设备工作原理,提出常见故障分析与维修思路,并结合实际使用场景分析导致PDA损坏的原因,总结易损配件的日常维护及注意事项。 展开更多
关键词 PDA 按键 micro USB 扫描头
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