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Structural color from basic principles to emerging applications
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作者 Dohyun Kang Junsuk Rho 《Opto-Electronic Advances》 2025年第4期1-3,共3页
Wenhao Wang and colleagues summarized the latest advancements in structural color research in Opto-Electronic Science. Their review explored the fundamental principles and fabrication methods of structural colors for ... Wenhao Wang and colleagues summarized the latest advancements in structural color research in Opto-Electronic Science. Their review explored the fundamental principles and fabrication methods of structural colors for photonic applications, including anti-counterfeiting, displays, sensors, and printing, along with their practical limitations. Recently, structural colors have received growing interest due to their advantages, including physical and chemical robustness, ecofriendliness, tunability, and high-resolution color. 展开更多
关键词 structural colors anti counterfeiting SENSORS DISPLAYS structural color nanofabrication PRINTING optical applications
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Intricate Fault Systems in Longmenshan Structural Belt's Northern End:Exploring Structural Evolution and Seismic Rupture Behavior in the Eastern Tibetan Plateau
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作者 Hanyu Huang Renqi Lu +3 位作者 Dengfa He Jinliang Gao Weikang Zhang Lingyu Kang 《Journal of Earth Science》 2025年第1期250-265,共16页
The Longmenshan structural belt on the eastern edge of the Tibetan Plateau experienced the impactful Mw7.92008 Wenchuan Earthquake,causing a 350 km surface rupture.Traditional models attribute this to the Beichuan and... The Longmenshan structural belt on the eastern edge of the Tibetan Plateau experienced the impactful Mw7.92008 Wenchuan Earthquake,causing a 350 km surface rupture.Traditional models attribute this to the Beichuan and Pengguan faults,but our research reveals a complex fault system at the northern end,with inconsistencies in surface rupture,aftershock distribution,and focal mechanisms.We integrate shallow geology,active source seismic reflection,and magnetotelluric profiling to establish a deep structural model for the northern end of the Longmenshan structural belt.This area exhibits dominant reverse thrust nappe tectonics,and analyzing the tectonic evolution history provides insights into deformation propagation from the orogenic belt toward the Sichuan Basin.Focal mechanism analysis and relocated aftershock data reveals two distinct types of seismogenic structures in the northern end of the Longmenshan structural belt.In the middle to northern segments,the reverse fault type is attributed to reactivated pre-existing faults.Conversely,at the northern end,the strike-slip fault type originates from high-angle co-seismic rupture cutting through pre-existing reverse faults.This study enhances our understanding of fault complexity and seismic mechanisms in the northeastern Longmenshan structural belt,providing new insights into regional tectonics. 展开更多
关键词 Longmenshan structural belt fault system structural evolution TECTONICS EARTHQUAKES focal mechanism
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Erratum to"GenomeSyn:a bioinformatics tool for visualizing genome synteny and structural variations"[J.Genet.Genom.(2022)49,11741176]
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作者 Zu-Wen Zhou Zhi-Guang Yu +4 位作者 Xiao-Ming Huang Jin-Shen Liu Yi-Xiong Guo Ling-Ling Chen Jia-Ming Song 《Journal of Genetics and Genomics》 2025年第8期1068-1069,共2页
Fig.1.The GenomeSyn tool for visualizing genome synteny and characterizing structural variations.A:The first synteny visualization map showed the detailed information of two or three genomes and can display structural... Fig.1.The GenomeSyn tool for visualizing genome synteny and characterizing structural variations.A:The first synteny visualization map showed the detailed information of two or three genomes and can display structural variations and other annotation information.B:The second type of visualization map was simple and only showed the synteny relationship between the chromosomes of two or three genomes.C:Multiplatform general GenomeSyn submission page,applicable to Windows,MAC and web platforms;other analysis files can be entered in the"other"option.The publisher would like to apologise for any inconvenience caused. 展开更多
关键词 two three genomes structural variations synteny relationship genomesyn visualizing genome synteny characterizing structural variationsa genome synteny synteny visualization map
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Mineralization at Different Structural Levels in the Crust
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作者 LI Saisai ZHANG Hongrui HOU Zengqian 《Acta Geologica Sinica(English Edition)》 2025年第4期1042-1058,共17页
Metallogenic research on structural levels can reveal vertical patterns of mineralization and facilitate the deep exploration of economic minerals.However,research focusing on the correlation between structural levels... Metallogenic research on structural levels can reveal vertical patterns of mineralization and facilitate the deep exploration of economic minerals.However,research focusing on the correlation between structural levels and mineralization remains limited.In this study,we summarize the deformation patterns and associated mineral deposits observed at different crustal levels(i.e.,surface,shallow,middle,and deep structural levels,corresponding to depths of<2,2-8,8-15,and>15 km,respectively).Furthermore,we examine the genetic association between structural levels and metallogenesis,demonstrating that distinct structural levels are linked to specific types of mineralization.Key factors that vary across crustal levels include temperature,pressure,and fluid circulation.Ore-forming processes involve interactions between structures and fluids under varying temperatures and pressures.Structural levels influence mineralization by controlling the temperatures,pressures,and deformation mechanisms that drive the activation,migration,and enrichment of ore-forming materials. 展开更多
关键词 deformation MINERALIZATION structural control structural level crustal level
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Preliminary hydrogeological implications using structural analysis and cave mapping:a case study of the Pachnes Thrust,Central Lefka Ori,Crete
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作者 Daniel Moraetis Aris Leontaritis +12 位作者 Andreas Scharf Charalampos Fassoulas Stylianos Zacharias Arnauld Malard Frank Mattern Asma Alnaqbi Hamdan Hamdan Markos Digenis Christos Pennos Kostas Adamopoulos Xuan Yu Nikolaos Nikolaidis Kosmas Pavlopoulos 《Episodes》 2025年第4期385-401,共17页
This multidisciplinary study integrates structural and cave mapping,3D geological modeling,and Geographical Information System(GIS)analysis to provide constraints of the hydrogeological model for the central Lefka Ori... This multidisciplinary study integrates structural and cave mapping,3D geological modeling,and Geographical Information System(GIS)analysis to provide constraints of the hydrogeological model for the central Lefka Ori Massif.Through 44 km of linear mapping,we discovered the new mid-Miocene Pachnes Thrust(PT)which plays a key role in the central Lefka Ori Massif structural framework. 展开更多
关键词 hydrogeological model structural analysis hydrogeological implications linear mappingwe structural cave mapping d geological modelingand D geological modeling cave mapping geographical information system gis analysis
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Acceleration Response Reconstruction for Structural Health Monitoring Based on Fully Convolutional Networks
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作者 Wenda Ma Qizhi Tang +2 位作者 Huang Lei Longfei Chang Chen Wang 《Structural Durability & Health Monitoring》 2025年第5期1265-1286,共22页
Lost acceleration response reconstruction is crucial for assessing structural conditions in structural health monitoring(SHM).However,traditional methods struggle to address the reconstruction of acceleration response... Lost acceleration response reconstruction is crucial for assessing structural conditions in structural health monitoring(SHM).However,traditional methods struggle to address the reconstruction of acceleration responses with complex features,resulting in a lower reconstruction accuracy.This paper addresses this challenge by leveraging the advanced feature extraction and learning capabilities of fully convolutional networks(FCN)to achieve precise reconstruction of acceleration responses.In the designed network architecture,the incorporation of skip connections preserves low-level details of the network,greatly facilitating the flow of information and improving training efficiency and accuracy.Dropout techniques are employed to reduce computational load and enhance feature extraction.The proposed FCN model automatically extracts high-level features from the input data and establishes a nonlinearmapping relationship between the input and output responses.Finally,the accuracy of the FCN for structural response reconstructionwas evaluated using acceleration data from an experimental arch rib and comparedwith several traditional methods.Additionally,this approach was applied to reconstruct actual acceleration responses measured by an SHM system on a long-span bridge.Through parameter analysis,the feasibility and accuracy of aspects such as available response positions,the number of available channels,and multi-channel response reconstruction were explored.The results indicate that this method exhibits high-precision response reconstruction capability in both time and frequency domains.,with performance surpassing that of other networks,confirming its effectiveness in reconstructing responses under various sensor data loss scenarios. 展开更多
关键词 structural health monitoring acceleration response reconstruction fully convolutional network experimental validation large-scale structural application
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Guided Wave Based Composite Structural Fatigue Damage Monitoring Utilizing the WOA-BP Neural Network
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作者 Borui Wang Dongyue Gao +2 位作者 Haiyang Gu Mengke Ding Zhanjun Wu 《Computers, Materials & Continua》 2025年第4期455-473,共19页
Fatigue damage is a primary contributor to the failure of composite structures,underscoring the critical importance of monitoring its progression to ensure structural safety.This paper introduces an innovative approac... Fatigue damage is a primary contributor to the failure of composite structures,underscoring the critical importance of monitoring its progression to ensure structural safety.This paper introduces an innovative approach to fatigue damage monitoring in composite structures,leveraging a hybrid methodology that integrates the Whale Optimization Algorithm(WOA)-Backpropagation(BP)neural network with an ultrasonic guided wave feature selection algorithm.Initially,a network of piezoelectric ceramic sensors is employed to transmit and capture ultrasonic-guided waves,thereby establishing a signal space that correlates with the structural condition.Subsequently,the Relief-F algorithm is applied for signal feature extraction,culminating in the formation of a feature matrix.This matrix is then utilized to train the WOA-BP neural network,which optimizes the fatigue damage identification model globally.The proposed model’s efficacy in quantifying fatigue damage is tested against fatigue test datasets,with its performance benchmarked against the traditional BP neural network algorithm.The findings demonstrate that the WOA-BP neural network model not only surpasses the BP model in predictive accuracy but also exhibits enhanced global search capabilities.The effect of different sensor-receiver path signals on the model damage recognition results is also discussed.The results of the discussion found that the path directly through the damaged area is more accurate in modeling damage recognition compared to the path signals away from the damaged area.Consequently,the proposed monitoring method in the fatigue test dataset is adept at accurately tracking and recognizing the progression of fatigue damage. 展开更多
关键词 structural health monitoring ultrasonic guided wave composite structural fatigue damage monitoring WOA-BP neural network relief-F algorithm
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AI-Driven Occupational Structural Transformation and Service-Oriented Manufacturing
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作者 Pan Shan Guo Kaiming 《China Economist》 2025年第4期56-79,共24页
Occupational structural transformation is a common pattern during the steady growth of GDP per capita in major economies worldwide.In recent years,there has been a decline in the employment share of goods occupation a... Occupational structural transformation is a common pattern during the steady growth of GDP per capita in major economies worldwide.In recent years,there has been a decline in the employment share of goods occupation and an increase in service occupation within the Chinese manufacturing industry,presenting a trend of occupational structural transformation and rapid development of service-oriented manufacturing.It is an important driving force and typical performance of the high-end,intelligent,and green development of the manufacturing industry.As a strategic general technology which leads the new round of technological revolution and industrial transformation,artificial intelligence(AI)has become a new fundamental force to accelerate the occupational structural transformation and service-oriented manufacturing development in China.Thus,this paper establishes a dynamic general equilibrium model with AI technology and occupational heterogeneity,showing the endogenous mechanism of occupational structural transformation.We find that when AI technology is biased towards goods occupation,and the elasticity of substitution between goods occupation and service occupation is less than 1,then AI will drive the transformation of occupational structure from goods to service within the manufacturing sector,increase the proportion of service-oriented manufacturing,improve labor productivity of manufacturing relative to service and stabilize the real output share of manufacturing.Promoting deeper integration of different occupations,intensifying R&D in AI technology and reducing labor mobility barriers between occupations can effectively accelerate the occupational structural transformation and industrial structural upgrading.We use theoretical analysis and numerical simulation method to show the theoretical mechanism by which AI affects occupational structural transformation and industrial structural transformation from a macroeconomic perspective,and put forward policy implications on how to promote the service-oriented manufacturing development and accelerate the construction of modern industrial system through AI innovation. 展开更多
关键词 Artificial intelligence occupational structural transformation service-oriented manufacturing industrial structural transformation
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High efficiency electromagnetic waves absorption of ferrite/polypyrrole composite based on precise structural control of rare earth doping
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作者 Hao Shi Han Gao +7 位作者 Long Qin Jiang-Tao Yuan Lin-Xuan Tang Zhuo-Rui Wang Wei-Jin Li Zeng-Hui Feng Yang Wang A-Ming Xie 《Rare Metals》 2025年第8期5621-5632,共12页
Structural manipulation plays a crucial role in material design,exerting a significant influence on various aspects of material performance.However,the impact of material microstructure on electromagnetic waves absorp... Structural manipulation plays a crucial role in material design,exerting a significant influence on various aspects of material performance.However,the impact of material microstructure on electromagnetic waves absorption properties has not been thoroughly investigated.In this study,based on ferrites,we controlled the micros tructural morphology by doping with light rare earth element Nd,and then formed heterogeneous structures through composite polypyrrole to enhance its performance.The structural changes in neodymium-doped ferrites and their corresponding variations in performance were systematically analyzed.The results indicate that Nd^(3+)ions doping has a pronounced effect on the microstructure of ferrites,significantly improving their dielectric loss capability for electromagnetic waves.The sample with optimal performance,Sr_(0.75)Nd_(0.25)Co_(2)Fe_(16)O_(27)@PPy,has a value of minimum reflection loss that can reach-63.11 dB,and the effective absorption bandwidth achieves 6.40 GHz at2.27 mm.This study provides instructive thinking for the structural manipulation of MA materials. 展开更多
关键词 structural regulation Microstructural morphology FERRITE Rare earth element Electromagnetic wave absorption
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Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations:A Review 被引量:5
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作者 Chao Zhang Shang-Xi Lai Hua-Ping Wang 《Structural Durability & Health Monitoring》 EI 2025年第1期25-54,共30页
Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters accordi... Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientific basis for structural damage identification and dynamic model modification.In view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and briefly describes how to identify structural damages based on the derived modal parameters.The paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),briefly describes damage identification methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artificial intelligence(AI)methods in the direction of modal parameter recognition and damage identification is further discussed.Based on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identification methods are given to provide scientific references for the optimized design and functional upgrading of SHM systems. 展开更多
关键词 structural health monitoring data information modal parameters damage identification AI method
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Status and Development of Rapid Detection Technology for Tunnel Structural Defects 被引量:4
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作者 LIU Xuezeng FANG Maoliu +3 位作者 WU Dexing LI Yinping LIU Xingen LI Gang 《隧道建设(中英文)》 北大核心 2025年第4期657-676,I0005-I0024,共40页
Based on inspection data,the authors analyze and summarize the main types and distribution characteristics of tunnel structural defects.These defects are classified into three types:surface defects,internal defects,an... Based on inspection data,the authors analyze and summarize the main types and distribution characteristics of tunnel structural defects.These defects are classified into three types:surface defects,internal defects,and defects behind the structure.To address the need for rapid detection of different defect types,the current state of rapid detection technologies and equipment,both domestically and internationally,is systematically reviewed.The research reveals that surface defect detection technologies and equipment have developed rapidly in recent years.Notably,the integration of machine vision and laser scanning technologies have significantly improved detection efficiency and accuracy,achieving crack detection precision of up to 0.1 mm.However,the non-contact rapid detection of internal and behind-the-structure defects remains constrained by hardware limitations,with traditional detection remaining dominant.Nevertheless,phased array radar,ultrasonic,and acoustic vibration detection technologies have become research hotspots in recent years,offering promising directions for detecting these challenging defect types.Additionally,the application of multisensor fusion technology in rapid detection equipment has further enhanced detection capabilities.Devices such as cameras,3D laser scanners,infrared thermal imagers,and radar demonstrate significant advantages in rapid detection.Future research in tunnel inspection should prioritize breakthroughs in rapid detection technologies for internal and behind-the-structure defects.Efforts should also focus on developing multifunctional integrated detection vehicles that can simultaneously inspect both surface and internal structures.Furthermore,progress in fully automated,intelligent systems with precise defect identification and real-time reporting will be essential to significantly improve the efficiency and accuracy of tunnel inspection. 展开更多
关键词 TUNNEL structural defect inspection techniques inspection equipment rapid inspection
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Role of iron ore in enhancing gasification of iron coke:Structural evolution,influence mechanism and kinetic analysis 被引量:1
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作者 Jie Wang Wei Wang +4 位作者 Xuheng Chen Junfang Bao Qiuyue Hao Heng Zheng Runsheng Xu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期58-69,共12页
The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the micro... The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was investigated.Furthermore,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric method.The findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and interconnect.This provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron coke.Accelerating the heating rate in non-isothermal gasification can enhance the reactivity of iron coke.The metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon atoms.The kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore structure.Moreover,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%. 展开更多
关键词 low-carbon ironmaking iron coke GASIFICATION structural evolution kinetic model
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Structural Color Dynamic Graphics Display Based on Microlens Array 被引量:1
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作者 LI Xue-han LIU Ling-zhi +1 位作者 HUANG Min LI Xiu 《印刷与数字媒体技术研究》 北大核心 2025年第2期162-168,共7页
It is of great scientific significance to construct a 3D dynamic structural color with a special color effect based on the microlens array.However,the problems of imperfect mechanisms and poor color quality need to be... It is of great scientific significance to construct a 3D dynamic structural color with a special color effect based on the microlens array.However,the problems of imperfect mechanisms and poor color quality need to be solved.A method of 3D structural color turning on periodic metasurfaces fabricated by the microlens array and self-assembly technology was proposed in this study.In the experiment,Polydimethylsiloxane(PDMS)flexible film was used as a substrate,and SiO2 microspheres were scraped into grooves of the PDMS film to form 3D photonic crystal structures.By adjusting the number of blade-coated times and microsphere concentrations,high-saturation structural color micropatterns were obtained.These films were then matched with microlens arrays to produce dynamic graphics with iridescent effects.The results showed that by blade-coated two times and SiO2 microsphere concentrations of 50%are the best conditions.This method demonstrates the potential for being widely applied in the anticounterfeiting printing and ultra-high-resolution display. 展开更多
关键词 structural color Microlens array Dynamic graphics display Moirémagnification Optical anti-counterfeiting
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Research progress of structural regulation and composition optimization to strengthen absorbing mechanism in emerging composites for efficient electromagnetic protection 被引量:4
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作者 Pengfei Yin Di Lan +7 位作者 Changfang Lu Zirui Jia Ailing Feng Panbo Liu Xuetao Shi Hua Guo Guanglei Wu Jian Wang 《Journal of Materials Science & Technology》 2025年第1期204-223,共20页
With the increasing complexity of the current electromagnetic environment,excessive microwave radi-ation not only does harm to human health but also forms various electromagnetic interference to so-phisticated electro... With the increasing complexity of the current electromagnetic environment,excessive microwave radi-ation not only does harm to human health but also forms various electromagnetic interference to so-phisticated electronic instruments.Therefore,the design and preparation of electromagnetic absorbing composites represent an efficient approach to mitigate the current hazards of electromagnetic radiation.However,traditional electromagnetic absorbers are difficult to satisfy the demands of actual utilization in the face of new challenges,and emerging absorbents have garnered increasing attention due to their structure and performance-based advantages.In this review,several emerging composites of Mxene-based,biochar-based,chiral,and heat-resisting are discussed in detail,including their synthetic strategy,structural superiority and regulation method,and final optimization of electromagnetic absorption ca-pacity.These insights provide a comprehensive reference for the future development of new-generation electromagnetic-wave absorption composites.Moreover,the potential development directions of these emerging absorbers have been proposed as well. 展开更多
关键词 Microwave absorption structural regulation Performance optimization Emerging composites Synthetic strategy
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Structural design in re duce d graphene oxide(RGO)metacomposites for enhanced microwave absorption in wide temperature spectrum 被引量:4
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作者 Haoxu Si Yi Zhang +5 位作者 Yuhao Liu Zhiyang Jiang Cuiping Li Jingwei Zhang Xiaoxiao Huang Chunhong Gong 《Journal of Materials Science & Technology》 2025年第3期211-220,共10页
High-temperature microwave absorbing materials(MAMs)and structures are increasingly appealing due to their critical role in stealth applications under harsh environments.However,the impedance mismatch caused by increa... High-temperature microwave absorbing materials(MAMs)and structures are increasingly appealing due to their critical role in stealth applications under harsh environments.However,the impedance mismatch caused by increased conduction loss often leads to a significant decline in electromagnetic wave absorp-tion(EMWA)performance at elevated temperatures,which severely restricts their practical application.In this study,we propose a novel approach for efficient electromagnetic wave absorption across a wide temperature range using reduced graphene oxide(RGO)/epoxy resin(EP)metacomposites that integrate both electromagnetic parameters and metamaterial design concepts.Due to the discrete distribution of the units,electromagnetic waves can more easily penetrate the interior of materials,thereby exhibiting stable microwave absorption(MA)performance and impedance-matching characteristics suitable across a wide temperature range.Consequently,exceptional MA properties can be achieved within the tem-perature range from 298 to 473 K.Furthermore,by carefully controlling the structural parameters in RGO metacomposites,both the resonant frequency and effective absorption bandwidth(EAB)can be optimized based on precise manipulation of equivalent electromagnetic parameters.This study not only provides an effective approach for the rational design of MA performance but also offers novel insights into achieving super metamaterials with outstanding performance across a wide temperature spectrum. 展开更多
关键词 Microwave absorbing materials Metacomposites Equivalent electromagnetic parameters structural parameters Wide temperature spectrum
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Structural designs and mechanism insights into electrocatalytic oxidation of 5-hydroxymethylfurfural 被引量:1
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作者 Jing Lei Huijie Zhang +4 位作者 Jian Yang Jia Ran Jiqiang Ning Haiyan Wang Yong Hu 《Journal of Energy Chemistry》 2025年第1期792-814,共23页
Biomass conversion offers an efficient approach to alleviate the energy and environmental issues.Electrochemical oxidation of 5-hydroxymethylfurfural(HMF)has attracted tremendous attention in the latest few years for ... Biomass conversion offers an efficient approach to alleviate the energy and environmental issues.Electrochemical oxidation of 5-hydroxymethylfurfural(HMF)has attracted tremendous attention in the latest few years for the mild synthesis conditions and high conversion efficiency to obtain 2,5-furan dicarboxylic acid(FDCA),but there still remain problems such as limited yield,short cycle life,and ambiguous reaction mechanism.Despite many reviews highlighting a variety of electrocatalysts for electrochemical oxidation of HMF,a detailed discussion of the structural modulation of catalyst and the underlying catalytic mechanism is still lacking.We herein provide a comprehensive summary of the recent development of electrochemical oxidation of HMF to FDCA,particularly focusing on the mechanism studies as well as the advanced strategies developed to regulate the structure and optimize the performance of the electrocatalysts,including heterointerface construction,defect engineering,single-atom engineering,and in situ reconstruction.Experimental characterization techniques and theoretical calculation methods for mechanism and active site studies are elaborated,and challenges and future directions of electrochemical oxidation of HMF are also prospected.This review will provide guidance for designing advanced catalysts and deepening the understanding of the reaction mechanism beneath electrochemical oxidation of HMF to FDCA. 展开更多
关键词 Electrochemical oxidation of 5- HYDROXYMETHYLFURFURAL 2 5-Furan dicarboxylic acid structural design MECHANISM ELECTROCATALYSTS
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Dynamic Structural Colors in Helical Superstructures:from Supramolecules to Polymers 被引量:1
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作者 Bo Ji Lang Qin Yan-Lei Yu 《Chinese Journal of Polymer Science》 2025年第3期406-428,共23页
Cholesteric liquid crystals(CLCs)exhibit unique helical superstructures that selectively reflect circularly polarized light,enabling them to dynamically respond to environmental changes with tunable structural colors.... Cholesteric liquid crystals(CLCs)exhibit unique helical superstructures that selectively reflect circularly polarized light,enabling them to dynamically respond to environmental changes with tunable structural colors.This dynamic color-changing capability is crucial for applications that require adaptable optical properties,positioning CLCs as key materials in advanced photonic technologies.This review focuses on the mechanisms of dynamic color tuning in CLCs across various forms,including small molecules,cholesteric liquid crystal elastomers(CLCEs),and cholesteric liquid crystal networks(CLCNs),and emphasizes the distinct responsive coloration each structure provides.Key developments in photochromic mechanisms based on azobenzene,dithienylethene,and molecular motor switches,are discussed for their roles in enhancing the stability and tuning range of CLCs.We examine the color-changing behaviors of CLCEs under mechanical stimuli and CLCNs under swelling,highlighting the advantages of each form.Following this,applications of dynamic color-tuning CLCs in information encryption,adaptive camouflage,and smart sensing technologies are explored.The review concludes with an outlook on current challenges and future directions in CLC research,particularly in biomimetic systems and dynamic photonic devices,aiming to broaden their functional applications and impact. 展开更多
关键词 structural colors Cholesteric liquid crystals Elastomers Polymer network
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Hydrodynamic Performance and Structural Response of a Sharp Eagle Wave Energy Converter Platform Under Extreme Sea States 被引量:1
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作者 YUE Wan-zhen WANG Kun-lin +4 位作者 JIANG Jia-qiang SHENG Song-wei LU Wen-zhao HE Teng YANG Xian-yuan 《China Ocean Engineering》 2025年第2期373-382,共10页
This paper presents a new type of triangular Sharp Eagle wave energy converter(WEC)platform.On the basis of the linear potential flow theory and the finite element analysis method,the hydrodynamic performance and stru... This paper presents a new type of triangular Sharp Eagle wave energy converter(WEC)platform.On the basis of the linear potential flow theory and the finite element analysis method,the hydrodynamic performance and structural response of the platform are studied,considering the actual platform motion and free surface rise under extreme sea states.First,the effects of the wave frequency and direction on the wave-induced loads and dynamic responses were examined.The motion at a wave direction angle of 0°is relatively low.On this basis,the angle constrained by the two sides of the Sharp Eagle floaters should be aligned with the main wave direction to avoid significant platform motion under extreme sea states.Additionally,the structural response of the platform,including the wave-absorbing floaters,is investigated.The results highlighted that the conditions or locations where yielding,buckling,and fatigue failures occur were different.In this context,the connection area of the Sharp Eagle floaters and platform is prone to yielding failure under oblique wave action,whereas the pontoon and side of the Sharp Eagle floaters are prone to buckling failure during significant vertical motion.Additionally,fatigue damage is most likely to occur at the connection between the middle column on both sides of the Sharp Eagle floaters and the pontoons.The findings of this paper revealed an intrinsic connection between wave-induced loads and the dynamic and structural responses of the platform,which provides a useful reference for the improved design of WECs. 展开更多
关键词 wave energy converter extreme sea states finite element analysis dynamic response structural response
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True triaxial unloading test on the mechanical behaviors of sandstone:Effects of the intermediate principal stress and structural plane 被引量:1
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作者 Fan Feng Zhiwei Xie +3 位作者 Shaojie Chen Diyuan Li Siyu Peng Tong Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2208-2226,共19页
A series of true triaxial unloading tests are conducted on sandstone specimens with a single structural plane to investigate their mechanical behaviors and failure characteristics under different in situ stress states... A series of true triaxial unloading tests are conducted on sandstone specimens with a single structural plane to investigate their mechanical behaviors and failure characteristics under different in situ stress states.The experimental results indicate that the dip angle of structural plane(θ)and the intermediate principal stress(σ2)have an important influence on the peak strength,cracking mode,and rockburst severity.The peak strength exhibits a first increase and then decrease as a function ofσ2 for a constantθ.However,whenσ2 is constant,the maximum peak strength is obtained atθof 90°,and the minimum peak strength is obtained atθof 30°or 45°.For the case of an inclined structural plane,the crack type at the tips of structural plane transforms from a mix of wing and anti-wing cracks to wing cracks with an increase inσ2,while the crack type around the tips of structural plane is always anti-wing cracks for the vertical structural plane,accompanied by a series of tensile cracks besides.The specimens with structural plane do not undergo slabbing failure regardless ofθ,and always exhibit composite tensile-shear failure whatever theσ2 value is.With an increase inσ2 andθ,the intensity of the rockburst is consistent with the tendency of the peak strength.By analyzing the relationship between the cohesion(c),internal friction angle(φ),andθin sandstone specimens,we incorporateθinto the true triaxial unloading strength criterion,and propose a modified linear Mogi-Coulomb criterion.Moreover,the crack propagation mechanism at the tips of structural plane,and closure degree of the structural plane under true triaxial unloading conditions are also discussed and summarized.This study provides theoretical guidance for stability assessment of surrounding rocks containing geological structures in deep complex stress environments. 展开更多
关键词 True triaxial unloading Dip angle of structural plane Intermediate principal stress Mechanical behaviors Cracking modes Failure criterion
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Accumulation mechanism and enrichment model of deep tight sandstone gas in second member of Upper Triassic Xujiahe Formation,Xinchang structural belt,Sichuan Basin,SW China 被引量:1
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作者 XIONG Liang CHEN Dongxia +3 位作者 YANG Yingtao ZHANG Ling LI Sha WANG Qiaochu 《Petroleum Exploration and Development》 2025年第4期907-920,共14页
Taking the second member of the Xujiahe Formation of the Upper Triassic in the Xinchang structural belt as an example,based on data such as logging,production,seismic interpretation and test,a systematic analysis was ... Taking the second member of the Xujiahe Formation of the Upper Triassic in the Xinchang structural belt as an example,based on data such as logging,production,seismic interpretation and test,a systematic analysis was conducted on the structural characteristics and evolution,reservoir diagenesis and densification processes,and types and stages of faults/fractures,and revealing the multi-stage and multi-factor dynamic coupled enrichment mechanisms of tight gas reservoirs.(1)In the early Yanshan period,the paleo-structural traps were formed with low-medium maturity hydrocarbons accumulating in structural highs driven by buoyancy since reservoirs were not fully densified in this stage,demonstrating paleo-structure control on traps and early hydrocarbon accumulation.(2)In the middle-late Yanshan period,the source rocks became mature to generate and expel a large quantity of hydrocarbons.Grain size and type of sandstone controlled the time of reservoir densification,which restricted the scale of hydrocarbon charging,allowing for only a small-scale migration through sand bodies near the fault/fracture or less-densified matrix reservoirs.(3)During the Himalayan period,the source rocks reached overmaturity,and the residual oil cracking gas was efficiently transported along the late-stage faults/fractures.Wells with high production capacity were mainly located in Type I and II fault/fracture zones comprising the late-stage north-south trending fourth-order faults and the late-stage fractures.The productivity of the wells was controlled by the transformation of the late-stage faults/fractures.(4)The Xinchang structural belt underwent three stages of tectonic evolution,two stages of reservoir formation,and three stages of fault/fractures development.Hydrocarbons mainly accumulated in the paleo-structure highs.After reservoir densification and late fault/fracture adjustment,a complex gas-water distribution pattern was formed.Thus,it is summarized as the model of“near-source and low-abundance hydrocarbon charging in the early stage,and differential enrichment of natural gas under the joint control of fault-fold-fracture complex,high-quality reservoirs and structural highs in the late stage”.Faults/fractures with well-coupled fault-fold-fracture-pore are favorable exploration targets with high exploration effectiveness. 展开更多
关键词 Upper Triassic second member of the Xujiahe Formation tight sandstone gas reservoir enrichment mechanism hydrocarbon accumulation model Xinchang structural belt Sichuan Basin
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