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距骨不同区域骨小梁形态特征的Micro-CT评估
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作者 李磊 张凤珍 +10 位作者 尹兆正 伊钰营 申晓科 段博 王志强 任小燕 李琨 李志军 王奇娇 王星 张少杰 《中国组织工程研究》 北大核心 2026年第15期3946-3952,共7页
背景:距骨骨折治疗难度大,易出现多种并发症,导致预后不良,故需进一步了解距骨内骨小梁分布特征及其与骨折发生的关系。目的:利用Micro-CT技术对距骨标本进行扫描,观测骨小梁结构特征及形态计量学参数,探讨距骨不同区域的骨小梁差异,为... 背景:距骨骨折治疗难度大,易出现多种并发症,导致预后不良,故需进一步了解距骨内骨小梁分布特征及其与骨折发生的关系。目的:利用Micro-CT技术对距骨标本进行扫描,观测骨小梁结构特征及形态计量学参数,探讨距骨不同区域的骨小梁差异,为距骨骨折的预防、治疗及骨折机制研究提供依据。方法:选取53例成人距骨标本进行Micro-CT扫描,将影像资料导入Avata软件进行三维重建,通过对距骨头部、颈部、体部3个感兴趣区域内骨小梁的勾选与重建,观察其形态特征,并测量分析不同区域骨小梁形态计量学参数的差异。结果与结论:①距骨的Micro-CT扫描影像显示其头部和体部的皮质骨较薄,而颈部的皮质骨则相对较厚;颈部的骨小梁分布较为稀疏,而头部和体部的骨小梁则相对致密;②距骨骨小梁的骨体积、骨体积分数、骨小梁模式因子在头部与颈部、体部间比较差异均有显著性意义(P<0.05);距骨骨小梁的骨表面积、骨表面积组织体积比、骨小梁分离度、分形维数在颈部与头部、体部间比较差异均有显著性意义(P<0.05);距骨骨小梁的骨小梁厚度在体部与头部、颈部之间比较差异有显著性意义(P<0.05);距骨骨小梁的骨表面积骨体积比、骨小梁厚度、骨小梁连通性、骨小梁连接密度、各向异性程度、结构模型指数在颈部与头部、体部,头部与体部间比较差异均有显著性意义(P<0.05);③提示Micro-CT技术能够定量分析距骨不同区域骨小梁形态的计量学参数,距骨的骨小梁形态计量学参数存在区域性差异,颈部的骨小梁数量和强度较低,是最容易发生骨折的部位,从骨小梁分布特征说明了距骨骨折好发于颈部。 展开更多
关键词 距骨 micro-CT 骨小梁 区域差异 形态计量学参数
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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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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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Microassembly:A Review on Fundamentals,Applications and Recent Developments
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作者 Yujian An Bingze He +2 位作者 Zhuochen Ma Yao Guo Guang-Zhong Yang 《Engineering》 2025年第5期323-346,共24页
Microassembly platforms have attracted significant attention recently because of their potential for developing microsystems and devices for a wide range of applications.Despite their considerable poten-tial,existing ... Microassembly platforms have attracted significant attention recently because of their potential for developing microsystems and devices for a wide range of applications.Despite their considerable poten-tial,existing techniques are mainly used in laboratory research settings.This review provides an over-view of the fundamentals,techniques,and applications of microassemblies.Manipulation techniques based on magnetic,optical,acoustic fields,and mechanical systems are discussed,and control systems that rely on machine vision and force feedback are introduced.Additionally,recent applications of microassemblies in microstructure fabrication,microelectromechanical operation,and biomedical engi-neering are examined.This review also highlights unmet technical demands and emerging trends,as well as new research opportunities in this expanding field of research driven by allied technologies such as microrobotics. 展开更多
关键词 microASSEMBLY microROBOTICS micro/nano-systems microelectromechanical systems Manipulation and control
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Micro-LED新型显示技术的现状、挑战及展望 被引量:2
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作者 庄喆 刘斌 《科技导报》 北大核心 2025年第2期42-51,共10页
微型发光二极管(Micro-LED)具有较好的稳定性,是当前高亮显示应用的最佳选择,其具有高对比度、低响应时间、宽工作温区、低能耗和广视角等优势,成为当前产业界和学术界比较看好的新型显示技术。综述了Micro-LED新型显示技术的原理,对比... 微型发光二极管(Micro-LED)具有较好的稳定性,是当前高亮显示应用的最佳选择,其具有高对比度、低响应时间、宽工作温区、低能耗和广视角等优势,成为当前产业界和学术界比较看好的新型显示技术。综述了Micro-LED新型显示技术的原理,对比其与现有技术的性能,从材料、器件、集成和成本良率等几个角度探讨了Micro-LED新型显示技术的关键技术挑战。未来3~5年内,Micro-LED显示技术仍然会在材料、器件、集成等技术方面存在技术创新和重大突破的关键机会,该技术支撑着未来显示产业的发展,也是中国科技创新引领全球的一次重要科技革命。建议鼓励创新,营造良好的科技创新环境,通过产学研合作解决当前Micro-LED新型显示技术的关键问题。同时发挥市场和社会资本的作用,引导产业遵循技术发展和商业发展规律。Micro-LED显示产业尽管仍面临技术挑战,但增强现实等近眼显示设备的推出,可能彻底革新现有的显示产品形态,Micro-LED显示产业市场将可能迎来爆发式增长。 展开更多
关键词 micro-LED新型显示 micro-LED芯片 技术挑战 产业发展
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Microwave biosensors utilizing metamaterial enhancement: Design and application
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作者 Jiaxu Wang Rongheng Wang +3 位作者 Zhou Shen Bohua Liu Chongling Sun Qiannan Xue 《Nanotechnology and Precision Engineering》 2025年第1期101-131,共31页
Microwave sensing technology has become increasingly widely applied in the biomedical field,playing a significant role in medical diagnosis,biological monitoring,and environmental warning.In recent years,the introduct... Microwave sensing technology has become increasingly widely applied in the biomedical field,playing a significant role in medical diagnosis,biological monitoring,and environmental warning.In recent years,the introduction of metamaterials has brought new possibilities and opportunities to microwave biosensors.This paper aims to explore the applications of microwave sensors in biosensing,with a particular emphasis on analyzing the crucial role of metamaterials in enhancing sensor performance and sensitivity.It provides a thorough examination of the fundamental principles,design strategies,fabrication techniques,and applications of microwave biosensors leveraging metamaterial enhancement.Moreover,it meticulously explores the latest applications spanning biomedical diagnostics,environmental monitoring,and food safety,shedding light on their transformative potential in healthcare,environmental sustainability,and food quality assurance.By delving into future research directions and confronting present challenges such as standardization and validation protocols,cost-effectiveness and scalability considerations and exploration of emerging applications,the paper provides a roadmap for advancing microwave biosensors with metamaterial enhancement,promising breakthroughs in multifaceted bioanalytical realms. 展开更多
关键词 microwave sensing METAMATERIAL Bioanalytical research Biomedical diagnostics micro-biosensor micro/NANOSTRUCTURE
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超声引导下甲状腺结节细针穿刺活检联合microRNA-221检测对甲状腺肿瘤检出率及肿瘤良恶性分级的价值研究
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作者 徐斌胜 占承志 汪倩 《影像科学与光化学》 2026年第1期87-93,共7页
目的:分析超声引导下甲状腺结节细针穿刺活检联合微小核糖核酸-221(microRNA-221)检测对甲状腺肿瘤的检出效能及对肿瘤良恶性分级的价值。方法:选取甲状腺肿瘤患者120例,分为良性组和恶性组,手术前均行超声引导下甲状腺结节细针穿刺活检... 目的:分析超声引导下甲状腺结节细针穿刺活检联合微小核糖核酸-221(microRNA-221)检测对甲状腺肿瘤的检出效能及对肿瘤良恶性分级的价值。方法:选取甲状腺肿瘤患者120例,分为良性组和恶性组,手术前均行超声引导下甲状腺结节细针穿刺活检,并检测microRNA-221表达。比较两组超声引导下细针穿刺活检结果、microRNA-221表达;比较不同超声表现及超声引导下细针穿刺活检分级患者microRNA-221表达;分析各指标单独及联合鉴别甲状腺肿瘤良恶性分级的效能。结果:有42例甲状腺恶性肿瘤、78例甲状腺良性肿瘤;两组超声引导下细针穿刺活检分级比较差异有统计学意义(P<0.05),恶性组Ⅱ级占比低于良性组(P<0.05),Ⅳ级、Ⅴ级、Ⅵ级占比均高于良性组(P<0.05),形态不规则、边界模糊、不均匀低回声、微小钙化患者血清、组织microRNA-221表达均更高(P<0.05),且恶性组血清、组织microRNA-221表达均高于良性组(P<0.05);超声引导下细针穿刺活检分级越高,血清、组织microRNA-221表达也越高;超声引导下细针穿刺活检、血清及组织microRNA-221表达结合诊断甲状腺肿瘤良恶性分级的灵敏度、准确率和AUC均高于单独诊断,特异度与单独诊断基本一致。结论:超声引导下甲状腺结节细针穿刺活检联合血清、组织microRNA-221检测可提高对甲状腺肿瘤良恶性分级的诊断灵敏度、准确率,且效能优于单一诊断。 展开更多
关键词 超声 甲状腺结节 细针穿刺活检 微小核糖核酸-221 甲状腺肿瘤 良恶性分级
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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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基于micro-LED的波分复用高速水下可见光通信系统研究
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作者 应红 张涛 +3 位作者 王彬峰 刘涛 唐堂 惠天宇 《照明工程学报》 2025年第5期60-73,共14页
本文研究了一种基于2个商用LED和5个自行设计micro-LED的波分复用(Wavelength Division Multiplexing,WDM)超高速水下可见光通信概念验证系统。通过预均衡和正交频分复用调制技术,在0.6 m水下环境中实现了28.82 Gbps的聚合通信速率,这... 本文研究了一种基于2个商用LED和5个自行设计micro-LED的波分复用(Wavelength Division Multiplexing,WDM)超高速水下可见光通信概念验证系统。通过预均衡和正交频分复用调制技术,在0.6 m水下环境中实现了28.82 Gbps的聚合通信速率,这是目前所知基于micro-LED的水下可见光通信(Underwater Visible Light Communication,UVLC)的破纪录传输速率,较现有最高纪录(20.09 Gbps)提升43%。相对单通道455 nm micro-LED(7.23 Gbps),容量增益达4倍。此外,本研究还分析了各波长光源的调制带宽与光功率特性,并利用63%和40%衰减片模拟扩展距离传输环境。采用63%衰减片的WDM-UVLC系统可获得聚合速率为18.35 Gbps,其中最短的估算传输距离为650 nm波长的光源,仅为1.81 m。使用40%衰减片的WDM-UVLC获得了15.36 Gbps的总通信速率,最短估算传输距离为2.75 m,而对于在水环境衰减特性小的蓝绿光则能够获得超过8 m的估算传输距离。尤其对于455 nm通道SNR仅下降5 dB即可维持BER<3.8×10^(-3),验证了方案在功率波动下的鲁棒性与潜力。该研究不仅验证了波分复用技术结合micro-LED在水下高速通信中的潜力,更表明多色micro-LED是波分复用UVLC发射器的绝佳候选器件,通过特定的光学滤波器和光学设计,未来可实现更集成的波分复用系统。 展开更多
关键词 水下可见光通信 波分复用 micro-LED 正交频分复用
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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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Micro-amplitude vibration-assisted scratching:a new method for one step and controllable fabrication of the microscale V-groove and nanoscale ripples
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作者 Haoxiang Wu Hu Huang +1 位作者 Zhiyu Zhang Jiwang Yan 《International Journal of Extreme Manufacturing》 2025年第3期398-421,共24页
Micro/nano hierarchical structures could endow materials with various surface functions.However,the multilayer and multiscale characteristics of micro/nano hierarchical structures bring difficulties for their one step... Micro/nano hierarchical structures could endow materials with various surface functions.However,the multilayer and multiscale characteristics of micro/nano hierarchical structures bring difficulties for their one step and controllable fabrication.Accordingly,based on tip-based fabrication techniques,this study proposed a micro-amplitude vibration-assisted scratching method by introducing a periodic backward displacement into the conventional scratching process,which enabled the synchronous creation of the microscale V-groove and nanoscale ripples,i.e.a typical micro/nano hierarchical structure.The experiments and finite element modeling were employed to explore the formation process and mechanism of the micro/nano hierarchical structures.Being different from conventional cutting,this method was mainly based on the plow mechanism,and it could accurately replicate the shape of the indenter on the material surface.The microscale V-groove was formed due to the scratching action,and the nanoscale ripple was formed due to the extrusion action of the indenter on the microscale V-groove’s surface.Furthermore,the relationships between the processing parameters and the dimensions of the micro/nano hierarchical structures were established through experiments,and optimized processing parameters were determined to achieve regular micro/nano hierarchical structures.By this method,complex patterns constructed by various micro/nano hierarchical structures were fabricated on both flat and curved surfaces,achieving diverse surface structural colors. 展开更多
关键词 vibration-assisted scratching tip-based micro/nano fabrication micro/nano hierarchical structure structural color
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Advances in micro/nanoparticle-enhanced Sn-based composite solders
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作者 Kaiming Liang Wenqiang Wan +4 位作者 Yifei Li Xin Zhang Xiangdong Ding Peng He Shuye Zhang 《International Journal of Minerals,Metallurgy and Materials》 2025年第9期2043-2064,共22页
Sn-based solder is a widely used interconnection material in the field of electronic packaging;however,the performance requirements for these solders are becoming increasingly demanding owing to the rapid development ... Sn-based solder is a widely used interconnection material in the field of electronic packaging;however,the performance requirements for these solders are becoming increasingly demanding owing to the rapid development in this area.In recent years,the addition of micro/nanoreinforcement phases to Sn-based solders has provided a solution to improve the intrinsic properties of the solders.This paper reviews the progress in Sn-based micro/nanoreinforced composite solders over the past decade.The types of reinforcement particles,preparation methods of the composite solders,and strengthening effects on the microstructure,wettability,melting point,mechanical properties,and corrosion resistance under different particle-addition levels are discussed and summarized.The mechanisms of performance enhancement are summarized based on material-strengthening effects such as grain refinement and second-phase dispersion strengthening.In addition,we discuss the current shortcomings of such composite solders and possible future improvements,thereby establishing a theoretical foundation for the future development of Sn-based solders. 展开更多
关键词 Sn-based composite solder micro/nanoparticles properties electronic packaging microstructure corrosion resistance
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Indentation-induced deformation twinning in magnesium:Phase-field modeling of microstructure evolution and size effects
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作者 Mohsen Rezaee-Hajidehi Przemysław Sadowski Stanisław Stupkiewicz 《Journal of Magnesium and Alloys》 2025年第4期1721-1742,共22页
Magnesium is distinguished by its highly anisotropic inelastic deformation involving a profuse activity of deformation twinning.Instrumented micro/nano-indentation technique has been widely applied to characterize the... Magnesium is distinguished by its highly anisotropic inelastic deformation involving a profuse activity of deformation twinning.Instrumented micro/nano-indentation technique has been widely applied to characterize the mechanical properties of magnesium,typically through the analysis of the indentation load-depth response,surface topography,and less commonly,the post-mortem microstructure within the bulk material.However,experimental limitations prevent the real-time observation of the evolving microstructure.To bridge this gap,we employ a recently-developed finite-strain model that couples the phase-field method and conventional crystal plasticity to simulate the evolution of the indentation-induced twin microstructure and its interaction with plastic slip in a magnesium single-crystal.Particular emphasis is placed on two aspects:orientation-dependent inelastic deformation and indentation size effects.Several outcomes of our 2D computational study are consistent with prior experimental observations.Chief among them is the intricate morphology of twin microstructure obtained at large spatial scales,which,to our knowledge,represents a level of detail that has not been captured in previous modeling studies.To further elucidate on size effects,we extend the model by incorporating gradient-enhanced crystal plasticity,and re-examine the notion of‘smaller is stronger’.The corresponding results underscore the dominant influence of gradient plasticity over the interfacial energy of twin boundaries in governing the size-dependent mechanical response. 展开更多
关键词 Magnesium alloys Deformation twinning micro/nano-indentation microstructure evolution Phase-field method Crystal plasticity
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Deciphering the potential mechanisms and influencing factors of the effects of micro(nano)plastics on microbe in sludge anaerobic digestion system
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作者 Weixin Zhao Shuocheng Shao +4 位作者 Hao Ma Jianyuan Zhen Shufei He Chuandong Wu Liangliang Wei 《Chinese Chemical Letters》 2025年第11期3-13,共11页
Approximately 99%of micro(nano)plastics in wastewater are retained in waste activated sludge,inhibiting anaerobic digestion,while their specific effects on functional microbes remain unclear.To break through the limit... Approximately 99%of micro(nano)plastics in wastewater are retained in waste activated sludge,inhibiting anaerobic digestion,while their specific effects on functional microbes remain unclear.To break through the limitations of current knowledge,in this review,we focused on summarizing the impacts of micro(nano)plastics on the microbial communities within anaerobic digestion systems,analyzing the toxicity mechanisms and developing strategies to mitigate their inhibitory effects.Firstly,the impacts of micro(nano)plastics on methane production and functional microbes were summarized,including direct cell pitting effects,inhibition caused by toxic leachates,and the adsorption of pollutants onto micro(nano)plastics surfaces,which further interfere with microbial activity and metabolic processes.Then,the specific performances and potential mechanisms by which micro(nano)plastics affect microbes were innovatively analyzed from the aspects of community variation,cellular activity and genetic expression.Moreover,various factors of micro(nano)plastics were found to influence their effects on microbes,including hormesis-like effects at different dosages,increased toxicity with decreasing particle size,enhanced biotoxicity due to surface functional groups,and variations in toxicity based on morphology and aggregation state.Furthermore,potential mitigation strategies,including activated carbon addition,thermal hydrolysis and cationic polyacrylamide application,were firstly summarized in here to alleviate inhibition on microbe.Finally,the current challenges and future directions were fully discussed and prospected.These insights could not only elucidate the biotoxic effects of micro(nano)plastics,but also provide a new avenue for helping to develop effective remediation techniques in micro(nano)plastic pollution management. 展开更多
关键词 micro(nano)plastics Mitigation strategy Biotoxicity microbial inhibition Anaerobic digestion
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Vat photopolymerization 3D printing of Al_(2)O_(3) ceramic cores with TPMS micro lattice structure
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作者 Xiao-fei Zhai Jing-yi Chen +4 位作者 Xue-qin Zhang Yuan-hong Qian Rong Chen Wei Zhang Ru-jie He 《China Foundry》 2025年第5期565-573,共9页
The complex ceramic core used for hollow turbine blades requires a high porosity and a high fiexural strength. For a better balance between porosity and fiexural strength, ceramic materials with porous structures are ... The complex ceramic core used for hollow turbine blades requires a high porosity and a high fiexural strength. For a better balance between porosity and fiexural strength, ceramic materials with porous structures are preferred. In order to achieve the transition from disordered pore formation to ordered pore formation, Al_(2)O_(3) ceramic cores with triply periodic minimal surface(TPMS) micro lattice structures with different structural configurations(gyroid, diamond, and neovius) and different volume fractions of lattice structures(30, 40, and 50, vol.%) were designed and prepared by vat photopolymerization 3D printing. The effects of structural configuration and volume fraction of the lattice structure on the following structural shrinkage, microstructure, and flexural strength were investigated. The shrinkage relationship of the three lattice configurations is: neovius>diamond>gyroid. Besides, it is found that with an increase in the volume fraction of the 3D printed Al_(2)O_(3) ceramic micro lattice structures, their fiexural strength correspondingly increases ranging from 54.95 MPa to 139.1 MPa. The maximum average fiexural strength of the 3D printed Al_(2)O_(3) ceramic micro lattice structures is obtained when the structural configuration is diamond and with a volume fraction of 50vol.%, which is 139.1 MPa. Even when the volume fraction of the lattice structure is 30vol.%, that is to say the porosity is 70%, the fiexural strength is as high as 50-70 MPa, which can still be maintained at a high level. In addition, when the volume fraction of the lattice structure is a certain value, the sample with diamond configuration has a higher strength. The internal pore morphology, pore size, and porosity of the cores are precisely controlled, achieving both a high porosity and a high strength. Therefore, this study maintains high porosity and high strength simultaneously, providing a new lattice structure design idea for 3D printed ceramic cores. 展开更多
关键词 alumina ceramic cores vat photopolymerization 3D printing micro lattice microstructure mechanical property
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Association among Noncoding-RNAs,APRO Family Proteins,and Gut Microbiota in the Development of Breast Cancer
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作者 Akari Fukumoto Satoru Matsuda 《Oncology Research》 2025年第9期2205-2219,共15页
The non-coding RNAs(ncRNAs)are a family of single-stranded RNAs that have become recognized as crucial gene expression regulators in normal and cancer cell biology.The gut microbiota,which consists of several differen... The non-coding RNAs(ncRNAs)are a family of single-stranded RNAs that have become recognized as crucial gene expression regulators in normal and cancer cell biology.The gut microbiota,which consists of several different bacteria,can actively contribute to the regulation of host metabolism,immunity,and inflammation.Roles of ncRNAs and gut microbiota could significantly interact with each other to regulate the growth of various types of cancer.In particular,a causal relationship among ncRNAs,gut microbiota,and immune cells has been shown for their potential importance in the development of breast cancer.Alteration of ncRNA expression and/or gut microbiota profiles could also influence several intracellular signaling pathways with the function of anti-proliferative(APRO)family proteins associated with the malignancy.Targeting ncRNAs and/or APRO family proteins for the treatment of various cancers has been revealed with novel immune therapies.Here,the most recent studies to underline the key role of ncRNAs,APRO family proteins,and gut microbiota in breast cancer progression have been discussed.For more effective breast cancer therapy,it would be imperative to figure out the collective mechanism of ncRNAs,APRO family proteins,and gut microbiota. 展开更多
关键词 Breast cancer cancer therapy non-coding RNAs(ncRNAs) micro RNA gut microbiota anti-proliferative(APRO)family protein
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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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基于Micro-CT分析大豆种子结构表型及构建种子重量预测模型 被引量:1
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作者 刘长斌 李远鲲 +3 位作者 郭民坤 樊江川 郭新宇 卢宪菊 《大豆科学》 北大核心 2025年第1期11-21,共11页
大豆是重要的粮油兼用作物,是植物蛋白质的重要来源,为明确大豆种子结构特征并构建种子重量预测模型,以42个不同大豆品种为材料,利用Micro-CT技术扫描测试样本,通过CT图像的处理解析,获取大豆种子的长度、宽度、厚度、体积、表面积、种... 大豆是重要的粮油兼用作物,是植物蛋白质的重要来源,为明确大豆种子结构特征并构建种子重量预测模型,以42个不同大豆品种为材料,利用Micro-CT技术扫描测试样本,通过CT图像的处理解析,获取大豆种子的长度、宽度、厚度、体积、表面积、种胚体积、表面积及空腔体积特征,人工称重测定单粒重量指标。系统分析种子形态特征及其与重量的相关关系,并对不同品种进行聚类分析,通过对多项形态表型和重量指标进行主成分分析,确定主要贡献指标,基于机器学习算法构建重量预测模型。结果表明:种子形态特征与种子重量显著相关,但种子形状特征对重量无显著影响;42个大豆品种可以分为4类,其中第一类品种蒙豆375和蒙豆60的种子大小和重量指标均显著高于其他3类品种。利用随机森林模型和偏最小二乘回归方法构建的重量预测模型效果优于单一指标的简单线性回归效果。其中,随机森林回归模型训练集和测试集的R^(2)分别为0.80和0.66,RMSE分别为0.017和0.021 g,偏最小二乘回归模型训练集和测试集的R^(2)分别为0.75和0.72,RMSE分别为0.019和0.020 g。研究结果为大豆种子外部形态和内部结构的研究提供了新的技术和方法,为大豆品种分类、产量和品质性状的评价提供理论和技术参考。 展开更多
关键词 micro-CT 大豆 结构表型 重量预测 模型构建 机器学习
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应用Micro-CT对老年人股骨头近端三柱骨微结构三维数字化测量
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作者 赵彬 李灿然 +8 位作者 张涛 如意 乌日汗 崔通力嘎 李筱贺 丁良甲 张凯 王海燕 王志强 《中国临床解剖学杂志》 北大核心 2025年第6期645-652,共8页
目的 研究老年人股骨近端三柱骨微结构相关参数,为临床人工股骨头设计和髋关节置换改良提供参考。方法 收集内蒙古医科大学人体解剖学实验室教学用(正常组)股骨标本30例,不讨论男女性别差异,年龄为60~80岁(平均68岁)均无骨盆、股骨手术... 目的 研究老年人股骨近端三柱骨微结构相关参数,为临床人工股骨头设计和髋关节置换改良提供参考。方法 收集内蒙古医科大学人体解剖学实验室教学用(正常组)股骨标本30例,不讨论男女性别差异,年龄为60~80岁(平均68岁)均无骨盆、股骨手术史,同时选取2023年内蒙古医科大学第二附属医院行CT检查为病例股骨头9例(为坏死组),其中3例标本为ARCOⅢ期,6例标本为ARCOⅣ期标本,采用Micro-CT扫描,扫描后利用重建软件进行三维重建并测量股骨头三柱结构(基于中日友好医院提出的CJFH分型,将股骨头分为外侧柱、中间柱、内侧柱,其中外侧柱占30%,中间柱占40%,内侧柱占30%)的总体积、骨体积、骨表面密度、骨小梁厚度、间隙、数量、连通性、体积分数等8项参数,分析不同区域骨质微观结构的差别。结果 正常组三柱间连通性差异无统计学意义,总体积、骨体积、骨密度、骨小梁间隙、骨小梁厚度、骨小梁数量、骨体积分数等参数差异均有统计学意义(P<0.05),总体积:中间柱、外侧柱>内侧柱;骨体积、骨表面密度:中间柱>内、外侧柱(P<0.05);骨小梁厚度:中间柱<内、外侧柱(P<0.05);体积分数、骨小梁数量:外侧柱<中间柱、内侧柱;骨小梁间隙:外侧柱>中间柱、内侧柱(P<0.05)。ARCOⅢ期坏死组内侧柱的总体积、骨体积、体积分数>正常组(P<0.05);ARCOⅢ期坏死组连通性<正常组。ARCOⅣ期坏死组中间柱的骨小梁厚度、骨小梁间隙>正常组;骨表面密度、骨小梁数量、连通性<正常组;内侧柱的总体积、骨体积、骨小梁厚度>正常组;骨表面密度、骨小梁数量<正常组。结论 正常组股骨头三柱结构中除连通性以外均有差异,坏死组与正常组股骨头三柱结构中骨微参数均有差异。 展开更多
关键词 股骨头 骨显微结构 micro-CT 数字化测量 老年
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