期刊文献+
共找到252,520篇文章
< 1 2 250 >
每页显示 20 50 100
Impact of pitch fraction oxidation on the structure and sodium storage properties of derived carbon materials 被引量:1
1
作者 QI Su-xia YANG Tao +6 位作者 SONG Yan ZHAO Ning LIU Jun-qing TIAN Xiao-dong WU Jin-ru LI Hui LIU Zhan-jun 《新型炭材料(中英文)》 北大核心 2025年第2期421-439,共19页
Pitch produced by the lique-faction of coal was divided into two frac-tions:soluble in toluene(TS)and insol-uble in toluene but soluble in pyridine(TI-PS),and their differences in molecu-lar structure and oxidation ac... Pitch produced by the lique-faction of coal was divided into two frac-tions:soluble in toluene(TS)and insol-uble in toluene but soluble in pyridine(TI-PS),and their differences in molecu-lar structure and oxidation activity were studied.Several different carbon materi-als were produced from them by oxida-tion in air(350℃,300 mL/min)fol-lowed by carbonization(1000℃ in Ar),and the effect of the cross-linked structure on their structure and sodium storage properties was investigated.The results showed that the two pitch fractions were obviously different after the air oxidation.The TS fraction with a low degree of condensation and abundant side chains had a stronger oxidation activity and thus introduced more cross-linked oxygen-containing functional groups C(O)―O which prevented carbon layer rearrangement during the carbonization.As a result,a disordered hard carbon with more defects was formed,which improved the electrochemical performance.Therefore,the carbon materials derived from TS(O-TS-1000)had an obvious disordered structure and a larger layer spacing,giving them better sodium storage perform-ance than those derived from the TI-PS fraction(O-TI-PS-1000).The specific capacity of O-TS-1000 was about 250 mAh/g at 20 mA/g,which was 1.67 times higher than that of O-TI-PS-1000(150 mAh/g). 展开更多
关键词 Pitch fractions Air oxidation Derived carbon materials Na^(+)storage
在线阅读 下载PDF
Nanograting‑Based Dynamic Structural Colors Using Heterogeneous Materials
2
作者 Jingang Wang Haibo Yu +6 位作者 Jianchen Zheng Yuzhao Zhang Hongji Guo Ye Qiu Xiaoduo Wang Yongliang Yang Lianqing Liu 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期138-151,共14页
Dynamic structuralcolors can change in response todifferent environmental stimuli.This ability remains effectiveeven when the size of the speciesresponsible for the structural coloris reduced to a few micrometers,prov... Dynamic structuralcolors can change in response todifferent environmental stimuli.This ability remains effectiveeven when the size of the speciesresponsible for the structural coloris reduced to a few micrometers,providing a promising sensingmechanism for solving microenvironmentalsensing problems inmicro-robotics and microfluidics.However, the lack of dynamicstructural colors that can encoderapidly, easily integrate, and accuratelyreflect changes in physical quantities hinders their use in microscale sensing applications. Herein, we present a 2.5-dimensionaldynamic structural color based on nanogratings of heterogeneous materials, which were obtained by interweaving a pH-responsive hydrogelwith an IP-L photoresist. Transverse gratings printed with pH-responsive hydrogels elongated the period of longitudinal grating in the swollenstate, resulting in pH-tuned structural colors at a 45° incidence. Moreover, the patterned encoding and array printing of dynamic structuralcolors were achieved using grayscale stripe images to accurately encode the periods and heights of the nanogrid structures. Overall, dynamicstructural color networks exhibit promising potential for applications in information encryption and in situ sensing for microfluidic chips. 展开更多
关键词 Dynamic structural colors Four-dimensional printing PH-RESPONSIVE Nanogrid Heterogeneous materials
在线阅读 下载PDF
Investigation of mixing performance and safety characteristics of polymer-based energetic materials simulant via screw-pressing blending extrusion charges 被引量:1
3
作者 Gaoming Lin Huzeng Zong +6 位作者 Suwei Wang Huang Chen Siyu Yu Xiaojie Hao Kang Wang Yuanyuan Li Guohui Zhang 《Defence Technology(防务技术)》 2025年第2期287-305,共19页
The present study introduces a screw-pressing charging method to tackle deficiencies in automation and charge uniformity during the melt-casting of polymer-based energetic materials.To ensure the safety of the experim... The present study introduces a screw-pressing charging method to tackle deficiencies in automation and charge uniformity during the melt-casting of polymer-based energetic materials.To ensure the safety of the experiments,this study used inert materials with similar physical properties to partially substitute for the actual energetic components in the preparation of simulant materials.By thoroughly analyzing slurry physical properties,a simulation framework and an extensive performance evaluation method were developed.Such tools guide the design of the structure and configuration of process parameters.Results demonstrate that employing the Pin element significantly enhances radial mixing within the screw,minimizes temperature variations in the slurry,and improves both efficiency and safety in the mixing process.Further,adjustments such as widening the cone angle of the barrel,modifying the solid content of the slurry,and varying the speed of the screw can optimize the mechanical and thermal coupling in the flow field.These adjustments promote higher-quality slurry and create a safer production environment for the extrusion process. 展开更多
关键词 Polymer-based energetic materials Screw-pressing charging process Structural design Process safety Mixing performance
在线阅读 下载PDF
Advanced Functional Electromagnetic Shielding Materials:A Review Based on Micro‑Nano Structure Interface Control of Biomass Cell Walls
4
作者 Yang Shi Mingjun Wu +14 位作者 Shengbo Ge Jianzhang Li Anoud Saud Alshammari Jing Luo Mohammed A.Amin Hua Qiu Jinxuan Jiang Yazeed M.Asiri Runzhou Huang Hua Hou Zeinhom M.El‑Bahy Zhanhu Guo Chong Jia Kaimeng Xu Xiangmeng Chen 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期98-134,共37页
Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and... Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and hierarchical.Due to their porous nature,interfacial compatibility,and electrical conductivity,biomass materials hold significant potential as EMI shielding materials.Despite concerted efforts on the EMI shielding of biomass materials have been reported,this research area is still relatively new compared to traditional EMI shielding materials.In particular,a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment,preparation process,and micro-control would be valuable.The preparation methods and characteristics of wood,bamboo,cellulose and lignin in EMI shielding field are critically discussed in this paper,and similar biomass EMI materials are summarized and analyzed.The composite methods and fillers of various biomass materials were reviewed.this paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field. 展开更多
关键词 Biomass materials Electromagnetic interference shielding Micro-nano structure interface control CONDUCTIVITY
在线阅读 下载PDF
Microstructure and Properties of Fe-Mo Functionally Graded Materials Fabricated by Electron Beam-Directional Energy Deposition
5
作者 Li Danni Yao Zhengjun +6 位作者 Yao Mengxin Zhang Shuxian Moliar Oleksandr Soloviova Tetiana Trosnikova Iryna Loboda Petro Zhang Shasha 《稀有金属材料与工程》 北大核心 2025年第3期554-568,共15页
Fe-Mo functionally graded materials(FGMs)with different composition-change rates from 100%304 stainless steel to 100%Mo along the composition gradient direction were prepared by electron beam-directed energy depositio... Fe-Mo functionally graded materials(FGMs)with different composition-change rates from 100%304 stainless steel to 100%Mo along the composition gradient direction were prepared by electron beam-directed energy deposition(EB-DED)technique,including three samples with composition mutation of 100%,composition change rate of 10%and 30%.Results show that the composition-change rate significantly affects the microstructure and mechanical properties of the samples.In the sample with abrupt change of composition,the sharp shift in composition between 304 stainless steel and Mo leads to a great difference in the microstructure and hardness near the interface between the two materials.With the increase in the number of gradient layers,the composition changes continuously along the direction of deposition height,and the microstructure morphology shows a smooth transition from 304 stainless steel to Mo,which is gradually transformed from columnar crystal to dendritic crystal.Elements Fe,Mo,and other major elements transform linearly along the gradient direction,with sufficient interlayer diffusion between the deposited layers,leading to good metallurgical bonding.The smaller the change in composition gradient,the greater the microhardness value along the deposition direction.When the composition gradient is 10%,the gradient layer exhibits higher hardness(940 HV)and excellent resistance to surface abrasion,and the overall compressive properties of the samples are better,with the compressive fracture stress in the top region reaching 750.05±14 MPa. 展开更多
关键词 functionally graded materials EB-DED microstructure evolution mechanical properties
原文传递
Microstructure modulation strategies from pitch molecules to derived carbon materials for electrochemical energy storage
6
作者 MENG Chao ZHANG Yan +4 位作者 WANG Ning ZHENG Xue-qing KONG De-yu HU Han WU Ming-bo 《新型炭材料(中英文)》 北大核心 2025年第4期837-859,共23页
Pitch is a complex mixture of polycyclic aromatic hydrocarbons and their non-metal derivatives that has a high carbon content.Using pitch as a precursor for carbon materials in alkali metal ion(Li^(+)/Na^(+)/K^(+))bat... Pitch is a complex mixture of polycyclic aromatic hydrocarbons and their non-metal derivatives that has a high carbon content.Using pitch as a precursor for carbon materials in alkali metal ion(Li^(+)/Na^(+)/K^(+))batteries has become of great interest.However,its direct pyrolysis often leads to microstructures with a high orientation and small interlayer spacing due to uncontrolled liquid-phase carbonization,resulting in subpar electrochemical performance.It is therefore important to control the microstructures of pitch-derived carbon materials in order to improve their electrochemical properties.We evaluate the latest progress in the development of these materials using various microstructural engineering approaches,highlighting their use in metal-ion batteries and supercapacitors.The advantages and limitations of pitch molecules and their carbon derivatives are outlined,together with strategies for their modification in order to improve their properties for specific applications.Future research possibilities for structure optimization,scalable production,and waste pitch recycling are also considered. 展开更多
关键词 Pitch precursor Carbon materials MICROSTruCTURE Modification strategies Electrochemical energy storage
在线阅读 下载PDF
Superstructured carbon materials:Progress and challenges in energy storage and conversion technologies
7
作者 ZUO Ming-xue HU Xia +6 位作者 KONG De-bin WEI Xin-ru QIN Xin LV Wei YANG Quan-Hong KANG Fei-yu ZHI Lin-jie 《新型炭材料(中英文)》 北大核心 2025年第4期962-972,共11页
Carbon materials are a key component in energy storage and conversion devices and their microstructure plays a crucial role in determining device performance.However,traditional carbon materials are unable to meet the... Carbon materials are a key component in energy storage and conversion devices and their microstructure plays a crucial role in determining device performance.However,traditional carbon materials are unable to meet the requirements for applications in emerging fields such as renewable energy and electric vehicles due to limitations including a disordered structure and uncontrolled defects.With an aim of realizing devisable structures,adjustable functions,and performance breakthroughs,superstructured carbons is proposed and represent a category of carbon-based materials,characterized by precisely-built pores,networks,and interfaces.Superstructured carbons can overcome the limitations of traditional carbon materials and improve the performance of energy storage and conversion devices.We review the structure-activity relationships of superstructured carbons and recent research advances from three aspects including a precisely customized pore structure,a dense carbon network framework,and a multi-component highly coupled interface between the different components.Finally,we provide an outlook on the future development of and practical challenges in energy storage and conversion devices. 展开更多
关键词 Carbon material application Superstructured carbons Energy storage and conversion
在线阅读 下载PDF
High voltage cathode materials for rechargeable magnesium batteries:Structural aspects and electrochemical perspectives
8
作者 Dedy Setiawan Jiwon Hwang +1 位作者 Munseok S.Chae Seung-Tae Hong 《Journal of Magnesium and Alloys》 2025年第9期4167-4188,共22页
Rechargeable magnesium batteries(RMBs)are a cutting-edge energy storage solution,with several advantages over the state-of-art lithiumion batteries(LIBs).The use of magnesium(Mg)metal as an anode material provides a m... Rechargeable magnesium batteries(RMBs)are a cutting-edge energy storage solution,with several advantages over the state-of-art lithiumion batteries(LIBs).The use of magnesium(Mg)metal as an anode material provides a much higher gravimetric capacity compared to graphite,which is currently used as the anode material in LIBs.Despite the significant advances in electrolyte,the development of cathode material is limited to materials that operate at low average discharge voltage(<1.0 V vs.Mg/Mg^(2+)),and developing high voltage cathodes remains challenging.Only a few materials have been shown to intercalate Mg^(2+)ions reversibly at high voltage.This review focuses on the structural aspects of cathode material that can operate at high voltage,including the Mg^(2+)intercalation mechanism in relation to its electrochemical properties.The materials are categorized into transition metal oxides and polyanions and subcategorized by the intrinsic Mg^(2+)diffusion path.This review also provides insights into the future development of each material,aiming to stimulate and guide researchers working in this field towards further advancements in high voltage cathodes. 展开更多
关键词 gravimetric capacity cathode material energy storage high voltage cathode materials anode material structural aspects lithiumion batteries libs rechargeable magnesium batteries
在线阅读 下载PDF
Very low Ru loadings boosting performance of Ni-based dual-function materials during the integrated CO_(2)capture and methanation process
9
作者 Anastasios I.Tsiotsias Eleana Harkou +8 位作者 Nikolaos D.Charisiou Victor Sebastian Dhanaji R.Naikwadi Bart van der Linden Atul Bansode Dragos Stoian George Manos Achilleas Constantinou Maria A.Goula 《Journal of Energy Chemistry》 2025年第3期309-328,共20页
Herein,the effect of the Ru:Ni bimetallic composition in dual-function materials(DFMs)for the integrated CO_(2)capture and methanation process(ICCU-Methanation)is systematically evaluated and combined with a thorough ... Herein,the effect of the Ru:Ni bimetallic composition in dual-function materials(DFMs)for the integrated CO_(2)capture and methanation process(ICCU-Methanation)is systematically evaluated and combined with a thorough material characterization,as well as a mechanistic(in-situ diffuse reflectance infrared fourier-transform spectroscopy(in-situ DRIFTS))and computational(computational fluid dynamics(CFD)modelling)investigation,in order to improve the performance of Ni-based DFMs.The bimetallic DFMs are comprised of a main Ni active metallic phase(20 wt%)and are modified with low Ru loadings in the 0.1-1 wt%range(to keep the material cost low),supported on Na_(2)O/Al_(2)O_(3).It is shown that the addition of even a very low Ru loading(0.1-0.2 wt%)can drastically improve the material reducibility,exposing a significantly higher amount of surface-active metallic sites,with Ru being highly dispersed over the support and the Ni phase,while also forming some small Ru particles.This manifests in a significant enhancement in the CH_(4)yield and the CH_(4)production kinetics during ICCU-Methanation(which mainly proceeds via formate intermediates),with 0.2 wt%Ru addition leading to the best results.This bimetallic DFM also shows high stability and a relatively good performance under an oxidizing CO_(2)capture atmosphere.The formation rate of CH_(4)during hydrogenation is then further validated via CFD modelling and the developed model is subsequently applied in the prediction of the effect of other parameters,including the inlet H_(2)concentration,inlet flow rate,dual-fu nction material weight,and reactor internal diameter. 展开更多
关键词 Dual-function materials Integrated CO_(2)capture and methanation Bimetallic materials Nickel-ruthenium Reducibility in-situ DRIFTS CFD modelling
在线阅读 下载PDF
Constructing the discrete gradient structure for enhancing interfacial bond strength of Ti6Al4V/NiTi heterostructured materials
10
作者 Xingran Li Qiang Li +4 位作者 Minghao Nie Pengfei Jiang Shenghong Yan Yue Jiang Zhihui Zhang 《Journal of Materials Science & Technology》 2025年第11期266-271,共6页
1.Introduction.The Ti6Al4V alloy is extensively utilized across various indus-trial sectors due to its favorable characteristics,such as lightweight design,high strength,and resistance to corrosion[1].In effort s to f... 1.Introduction.The Ti6Al4V alloy is extensively utilized across various indus-trial sectors due to its favorable characteristics,such as lightweight design,high strength,and resistance to corrosion[1].In effort s to further reduce weight,functional elements like electric actuators can be substituted with intelligent materials like shape memory alloys(SMAs)[2,3].Among SMAs,NiTi alloy stands out for its sens-ing and actuation capabilities,significantly enhancing the safety and reliability of engineering structures[4,5].Integrating Ti6Al4V and NiTi alloys within a single component holds the potential to provide precise feedback on mechanical,thermal,or environmen-tal conditions[6,7]. 展开更多
关键词 shape memory alloys smas ti al v alloy intelligent materials smasniti alloy NITI electric actuators engineering structu Heterostructured materials
原文传递
Nanosizing enhancement of hydrogen storage performance and mechanism in Mg-based materials:Nano-substrate modulation,nano-catalyst construction,and nano-catalytic mechanisms
11
作者 Duode Zhao Xiaojiang Hou +8 位作者 Yu Ge Dongfeng Sun Danting Li Chenlu Wang Xinlei Xie Peixuan Zhu Xiaohui Ye Guoquan Suo Yanling Yang 《Journal of Energy Chemistry》 2025年第10期609-636,共28页
The magnesium-based materials are acknowledged as one of the most promising solid-state hydrogen storage mediums,attributed to their superior hydrogen storage capacity.Nevertheless,challenges such as sluggish kinetics... The magnesium-based materials are acknowledged as one of the most promising solid-state hydrogen storage mediums,attributed to their superior hydrogen storage capacity.Nevertheless,challenges such as sluggish kinetics,thermodynamic stability,inadequate cycling stability,and difficulties in activation impede the commercial utilization of Mg-based composites.Research indicates that reducing material dimensions to the nanoscale represents an efficacious strategy to address these issues.In this work,we systematically analyze the impact of nanosizing on Mg-based composites from three perspectives:nano-substrate modulation,nano-catalyst construction,and nano-catalytic mechanism.This analysis aims to provide guidance for the optimization and development of nanosizing strategies.For the regulation of nanosizing of Mg-based composites,the nanosizing of multi-element micro-alloyed Mg-rich systems,the integrated synthesis of multi-element multi-component nano-catalysts,and the coexistence of multiple nano-catalytic mechanisms are proposed in the light of the current state of the art research,artificial intelligence technology,and advanced characterization technology to achieve efficient,multidimensional,and simultaneous regulation of the hydrogen storage performance of Mg-based composites.This paper also envisions future directions and potential applications,emphasizing the importance of interdisciplinary approaches that integrate material science,chemistry,and computational modeling to overcome existing limitations and unlock the full potential of Mg-based hydrogen storage technologies. 展开更多
关键词 Nanosizing Mg-based materials Substrate modulation Catalyst Catalytic mechanism
在线阅读 下载PDF
Use of Polymeric Materials in Construction to Improve Durability & Sustainability
12
作者 Waseem Ahmad Khatri Mohammed Al Mehthel +2 位作者 Oscar Salazar Mirza Baig Saleh Al Wohaibi 《World Journal of Engineering and Technology》 2025年第1期12-38,共27页
Building and construction sector, including infrastructures, are facing many challenges which are scarcity of raw materials, CO2 emissions, lower construction efficiency, and deterioration under corrosive environment ... Building and construction sector, including infrastructures, are facing many challenges which are scarcity of raw materials, CO2 emissions, lower construction efficiency, and deterioration under corrosive environment that cost the world economy $2.5 trillion and this translates to 3.4% of world gross domestic product. This paper presents several examples that show how the use of the nonmetallic materials improved sustainability and life cycles in the built environment by removing the corrosion issue from its root and using durable NM polymers in construction. The paper details recently patented Aramco technology for the use of nonmetallic paving panels that could be used as an alternative to concrete and asphalt paving. Other case studies presented cover use of GFRP Poles for traffic signs and signal poles to replace traditional steel poles. Details of developments for specialist structural application in bridges, in architectural applications, polymers in soils, fibers in pavement manholes and bendable concrete are presented. 展开更多
关键词 Non-Metallic materials Corrosion DURABILITY Non-Metallic Paving Metals Building and Construction Paving Panels Bridges ARCHITECTURAL Polymers Glass Fiber Reinforced Polymers (GFRP)
在线阅读 下载PDF
Mechanical Performance Analysis of Rubber Elastic Polymer-Polyurethane Reinforced Cement-Based Composite Grouting Materials
13
作者 Baoping Zou Jiahao Yin +1 位作者 Chunhui Cao Xu Long 《Journal of Polymer Materials》 2025年第1期255-275,共21页
The ongoing operation of subway systems makes existing tunnels vulnerable to deformations and structural damage caused by adjacent foundation pit construction.Such deformations-manifesting as horizontal displacement,h... The ongoing operation of subway systems makes existing tunnels vulnerable to deformations and structural damage caused by adjacent foundation pit construction.Such deformations-manifesting as horizontal displacement,heightened lateral convergence,and internal force redistribution-may significantly compromise subway operational safety.Grouting remediation has become a widely adopted solution for tunnel deformation control and structural reinforcement.Developing optimized grouting materials is crucial for improving remediation effectiveness,ensuring structural integrity,and maintaining uninterrupted subway operations.This investigation explores the substitution of fine mortar aggregates with 0.1 mm discarded rubber particles at varying concentrations(0%,3%,6%,9%,12%,and 15%).Experimental parameters included three water-cement ratios(0.65,0.70,and 0.75)with constant 4%WPU content.Mechanical properties including compressive strength,flexural strength,and compression-to-bending ratio were evaluated across specified curing periods.Material characterization employed Fourier Transform Infrared Spectroscopy(FTIR)spectroscopy for molecular analysis and Scanning Electron Microscopy(SEM)for microstructural examination.Results indicate optimal toughness at 0.70 water-cement ratio with 6%rubber content,meeting mechanical pumping specifications while maintaining structural performance. 展开更多
关键词 rubber particles POLYMER POLYURETHANE grouting material mechanical properties
在线阅读 下载PDF
Research on the Application of Local Materials in the Environmental Design of Rural Kindergartens
14
作者 Liping Qin Baoxia Yu 《Journal of World Architecture》 2025年第3期141-145,共5页
As the development of rural kindergarten education continues,creating an appropriate kindergarten environment has become an important issue.This paper focuses on the application of local materials in the design of rur... As the development of rural kindergarten education continues,creating an appropriate kindergarten environment has become an important issue.This paper focuses on the application of local materials in the design of rural kindergarten environments.Through in-depth research,it was found that local materials not only offer the advantages of being easily accessible and cost-effective but also enable the creation of learning and growth spaces for young children that are rich in regional characteristics.From indoor space layout,activity area division,to outdoor landscape design,the paper explores how to skillfully integrate local materials into design to stimulate children’s curiosity and creativity,while enhancing their understanding and identification with local culture.This provides feasible strategies and methods for optimizing the environment of rural kindergartens,thereby contributing to the improvement of educational quality in rural kindergartens. 展开更多
关键词 Local materials rural kindergartens Environmental design Educational quality
在线阅读 下载PDF
Enhancing hydrogen storage performance of magnesium-based materials:A review on nanostructuring and catalytic modification
15
作者 Chengguang Lang Xiangdong Yao 《Journal of Magnesium and Alloys》 2025年第2期510-538,共29页
Magnesium-based hydrogen storage materials are gaining significant attention due to their high hydrogen storage capacity and abundant availability.However,they encounter challenges,including slow hydrogen absorption a... Magnesium-based hydrogen storage materials are gaining significant attention due to their high hydrogen storage capacity and abundant availability.However,they encounter challenges,including slow hydrogen absorption and desorption kinetics and elevated operating temperatures.To address these issues,researchers have employed two main strategies:nanostructuring and the introduction of catalysts.This review provides a comprehensive overview of recent advancements in the modification of MgH_(2),emphasizing the impact of nanostructuring on enhancing hydrogen storage performance.It also examines the role of various catalysts,including carbon-based materials,transition metals and alloys,their oxides and halides,and composites,in improving hydrogen absorption and desorption characteristics.Studies indicate that these modifications can substantially lower the hydrogen absorption and desorption temperatures while enhancing kinetic performance.Furthermore,the effectiveness of catalysts is influenced by their type,dispersion,and interaction with magnesium-based materials and the catalytic mechanism,thereby elucidating the underlying catalytic mechanisms.The review concludes by discussing the current challenges and future directions in this field,aiming to provide theoretical insights for the practical application of magnesium-based hydrogen storage materials. 展开更多
关键词 Mg-based materials Hydrogen storage CATALYSIS Nanostructuring kinetics
在线阅读 下载PDF
A micromechanical friction-damage fatigue model of rock materials under cyclic loadings using a fractional plastic flow rule
16
作者 Jin Zhang Ke Ren +3 位作者 Zhigang Tao Tao Ni Qi-Zhi Zhu Jianfu Shao 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第10期6248-6263,共16页
This study is devoted to a novel fractional friction-damage model for quasi-brittle rock materials subjected to cyclic loadings in the framework of micromechanics.The total damage of material describing the microstruc... This study is devoted to a novel fractional friction-damage model for quasi-brittle rock materials subjected to cyclic loadings in the framework of micromechanics.The total damage of material describing the microstructural degradation is decomposed into two parts:an instantaneous part arising from monotonic loading and a fatigue-related one induced by cyclic loading,relating to the initiation and propagation of microcracks.The inelastic deformation arises directly from frictional sliding along microcracks,inherently coupled with the damage effect.A fractional plastic flow rule is introduced using stress-fractional plasticity operations and covariant transformation approach,instead of classical plastic flow function.Additionally,the progression of fatigue damage is intricately tied to subcracks and can be calculated through application of a convolution law.The number of loading cycles serves as an integration variable,establishing a connection between inelastic deformation and the evolution of fatigue damage.In order to verify the accuracy of the proposed model,comparison between analytical solutions and experimental data are carried out on three different rocks subjected to conventional triaxial compression and cyclic loading tests.The evolution of damage variables is also investigated along with the cumulative deformation and fatigue lifetime.The improvement of the fractional model is finally discussed by comparing with an existing associated fatigue model in literature. 展开更多
关键词 Fractional model MICROMECHANICS Fatigue damage Rock material Cyclic loadings
在线阅读 下载PDF
Integration of Biopolyesters and Natural Fibers in Structural Composites:An Innovative Approach for Sustainable Materials
17
作者 Nasmi Herlina Sari Suteja Widya Fatriasari 《Journal of Renewable Materials》 2025年第8期1521-1546,共26页
Composites made from biopolymers and natural fibers are gaining popularity as alternative sustainable structural materials.Biopolyesters including polylactic acid(PLA),polybutylene succinate(PBS),and polyhydroxyalkano... Composites made from biopolymers and natural fibers are gaining popularity as alternative sustainable structural materials.Biopolyesters including polylactic acid(PLA),polybutylene succinate(PBS),and polyhydroxyalkanoate(PHA),when mixed with natural fibers such as kenaf,hemp,and jute,provide an environmentally acceptable alternative to traditional fossil-based materials.This article examines current research on developments in the integration of biopolymers with natural fibers,with a focus on enhancing mechanical,thermal,and sustainability.Innovative approaches to surface treatment of natural fibers,such as biological and chemical treatments,have demonstrated enhanced adhesion with biopolymer matrices,increasing attributes such as tensile strength and rigidity.Furthermore,nano filling technologies such as nanocellulose and nanoparticles have improved the attributes of multifunctional composites,including heat conductivity and moisture resistance.According to performance analysis,biopolymernatural fiber-based composites may compete with synthetic composites in construction applications,particularly in lightweight buildings and automobiles.However,significant issues such as degradation in humid settings and longtermendurancemust be solved.To support a circular economy,solutions involve the development ofmoisture-resistant polymers and composite recycling technology.This article examines current advancements and identifies problems and opportunities to provide insight into the future direction of more inventive and sustainable biocomposites,and also the dangers they pose to green technology and industrial materials.These findings are significant in terms of the development of building materials which are not only competitive but also contribute to global sustainability. 展开更多
关键词 Biopolymers natural fibers sustainable composites material innovation green technology
在线阅读 下载PDF
High entropy nanomaterials for zero-emission energy systems:Advanced structural design,catalytic performance and functional mechanisms
18
作者 Zibo Zhai Yan-Jie Wang +2 位作者 Dan Liu Biao Wang Baizeng Fang 《Journal of Energy Chemistry》 2025年第8期512-532,共21页
High entropy materials(HEMs)are the promising electrocatalysts for anion exchange membrane electrolyser(AEMs)and proton exchange membrane fuel cells(PEMFCs)due to the intriguing cocktail effect,wide design space,tailo... High entropy materials(HEMs)are the promising electrocatalysts for anion exchange membrane electrolyser(AEMs)and proton exchange membrane fuel cells(PEMFCs)due to the intriguing cocktail effect,wide design space,tailorable electronic structure,and entropy stabilization effect.The precise fabrication of HEMs with functional nanostructures provides a crucial avenue to optimize the adsorption strength and catalytic activity for electrocatalysis.This review comprehensively summarizes the development of HEMs,focusing on the principles and strategies of structural design,and the catalytic mechanism towards hydrogen evolution reaction,oxygen evolution reaction and oxygen reduction reaction for the development of high-performance electrocatalysts.The complexity inherent in the interactions between different elements,the changes in the d-band center and the Gibbs free energies during the catalytic progress,as well as the coordination environment of the active sites associated with the unique crystal structure to improve the catalytic performance are discussed.We also provide a perspective on the challenges and future development direction of HEMs in electrocatalysis.This review will contribute to the design and development of HEMs-based catalysts for the next generation of electrochemical applications. 展开更多
关键词 High entropy materials Structural design Electrocatalytic performance Functional mechanism
在线阅读 下载PDF
Advanced Bismuth-Based Anode Materials for Efficient Potassium Storage:Structural Features,Storage Mechanisms and Modification Strategies
19
作者 Yiye Tan Fanglan Mo Hongyan Li 《Nano-Micro Letters》 2025年第6期1-39,共39页
Potassium-ion batteries(PIBs)are considered as a promising energy storage system owing to its abundant potassium resources.As an important part of the battery composition,anode materials play a vital role in the futur... Potassium-ion batteries(PIBs)are considered as a promising energy storage system owing to its abundant potassium resources.As an important part of the battery composition,anode materials play a vital role in the future development of PIBs.Bismuth-based anode materials demonstrate great potential for storing potassium ions(K^(+))due to their layered structure,high theoretical capacity based on the alloying reaction mechanism,and safe operating voltage.However,the large radius of K^(+)inevitably induces severe volume expansion in depotassiation/potassiation,and the sluggish kinetics of K^(+)insertion/extraction limits its further development.Herein,we summarize the strategies used to improve the potassium storage properties of various types of materials and introduce recent advances in the design and fabrication of favorable structural features of bismuth-based materials.Firstly,this review analyzes the structure,working mechanism and advantages and disadvantages of various types of materials for potassium storage.Then,based on this,the manuscript focuses on summarizing modification strategies including structural and morphological design,compositing with other materials,and electrolyte optimization,and elucidating the advantages of various modifications in enhancing the potassium storage performance.Finally,we outline the current challenges of bismuth-based materials in PIBs and put forward some prospects to be verified. 展开更多
关键词 Bismuth-based materials Potassium-ion batteries ANODE Potassium storage mechanism Modification strategies
在线阅读 下载PDF
Enhancement of Mechanical Properties of Natural Rubber Filled Activated Carbon Materials from Agricultural Waste
20
作者 Pollawat Charoeythornkhajhornchai Piyamas Saehia +2 位作者 Thidaporn Butchan Nawapol Lertumpai Worawut Muangrat 《Journal of Renewable Materials》 2025年第4期817-827,共11页
Herein,cure characteristics,morphology,and mechanical properties of natural rubber filled with activated carbon-based materials were investigated.Carbon-based materials were prepared from bagasse,coffee grounds and pi... Herein,cure characteristics,morphology,and mechanical properties of natural rubber filled with activated carbon-based materials were investigated.Carbon-based materials were prepared from bagasse,coffee grounds and pineapple crowns by the pyrolysis method at temperatures in the range of 300℃.As-synthesized carbon materials were characterized by optical microscopy(OM),scanning electron microscopy(SEM),and Fourier-transform infrared spectroscopy(FTIR)to analyze size distribution,morphology,and functional groups,respectively.OM and SEM analysis revealed that particles,flakes,and a small quantity of fiber-like carbon were obtained using bagasse and pineapple crown as raw materials,while honeycomb-like carbon materials can be derived from coffee grounds.To investigate the mechanical properties,natural rubber was filled with carbon black and as-synthesized carbon materials by the internal mixing and compression molding process.Transmission electron microscopy(TEM)was utilized to characterize the dispersion of carbon materials in the rubber matrix.The results of tensile testing showed that the natural rubber mixed with as-synthesized carbon materials from pineapple crowns exhibited 54%and 74%improvement in the ultimate tensile strength and Young’s modulus,respectively,compared with natural rubber without filled carbon materials.The enhancement in mechanical properties by activated carbon materials derived from pineapple crowns can be attributed to the flake-and fiber-like structures and good dispersion of carbon materials in the rubber matrix.In addition,it is higher than that of rubber mixed with carbon black.The results demonstrated that as-synthesized carbon materials from pineapple crowns have the potential materials to substitute carbon black in the rubber compound industry. 展开更多
关键词 Carbon materials agricultural waste natural rubber cure characteristics mechanical properties
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部