Moisture electricity generation(MEG)has emerged as a sustainable and versatile energy-harvesting technology capable of converting ubiquitous environmental moisture into electrical energy,which holds great promise for ...Moisture electricity generation(MEG)has emerged as a sustainable and versatile energy-harvesting technology capable of converting ubiquitous environmental moisture into electrical energy,which holds great promise for renewable energy and constructing self-powered electronics.In this review,we begin by outlining the fundamental mechanisms—ion diffusion,electric double layer formation,and streaming potential—that govern charge transport for MEG in moist environments.A comprehensive survey of material innovations follows,highlighting breakthroughs in carbon-based materials,conductive polymers,hydrogels,and bio-inspired systems that enhance MEG performance,scalability,and biocompatibility.We then explore a range of device architectures,from planar and layered systems to flexible,miniaturized,and textile-integrated designs,engineered for both energy conversion and sensor integration.Key challenges are analyzed,along with strategies for overcoming them.We conclude with a forward-looking perspective on future directions,including hybrid energy systems,AI-assisted material design,and real-world deployment.This review presents a timely and comprehensive overview of MEG technologies and their trajectory toward practical and sustainable energy solutions.展开更多
Investments in eco-friendly,recyclable material solutions and innovation in bio-based nonwovens are increasingly shaping the next generation of automotive interiors.The development of nonwoven materials and associated...Investments in eco-friendly,recyclable material solutions and innovation in bio-based nonwovens are increasingly shaping the next generation of automotive interiors.The development of nonwoven materials and associated technologies is likely to lead to even wider adoption in the automotive industry,driven by rising global vehicle production,particularly in the growing electric vehicle(EV)segment,and an intensified focus on sustainable solutions.展开更多
In the context of diminishing energy resources and worsening greenhouse effect,thermoelectric materials have great potential for sustainable development due to their green and environmentally friendly characteristics....In the context of diminishing energy resources and worsening greenhouse effect,thermoelectric materials have great potential for sustainable development due to their green and environmentally friendly characteristics.Among inorganic thermoelectric materials,copper sulfide compounds have greater potential than others due to their abundant element reserves on Earth,lower usage costs,non-toxicity,and good biocompatibility.Compared to organic thermoelectric materials,the"phonon liquid-electron crystal"(PLEC)feature of copper sulfide compounds makes them have stronger thermoelectric performance.This review summarizes the latest research progress in the synthesis methods and thermoelectric modification strategies of copper sulfide compounds.It first explains the importance of the solid-phase method in the manufacture of thermoelectric devices,and then focuses on the great potential of nanoscale synthesis technology based on liquid-phase method in the preparation of thermoelectric materials.Finally,it systematically discusses several strategies for regulating the thermoelectric performance of copper sulfide compounds,including adjusting the chemical proportion of Cu_(2-x)S and introducing element doping to regulate the crystal structure,phase composition,chemical composition,band structure,and nanoscale microstructure of copper sulfide compounds,and directly affecting ZT value by adjusting conductivity and thermal conductivity.In addition,it discusses composite engineering based on copper sulfide compounds,including inorganic,organic,and metal compounds,and discusses tri-component compounds derived from sulfide copper.Finally,it discusses the main challenges and prospects of the development of copper sulfide-based thermoelectric materials,hoping that this review will promote the development of copper sulfide-based thermoelectric materials.展开更多
Ultrasonic-Assisted Grinding(UAG)is a novel manufacturing technology that shows promising promise for use in processing Ceramic Matrix Composites(CMCs).Nevertheless,analyzing the material removal process of CMCs with ...Ultrasonic-Assisted Grinding(UAG)is a novel manufacturing technology that shows promising promise for use in processing Ceramic Matrix Composites(CMCs).Nevertheless,analyzing the material removal process of CMCs with multidirectional structure during UAG is challenging,impeding the progress and improvement of the UAG process.This work examined the impact of ultrasonic vibration on the dynamic mechanical characteristics during processing.Additionally,we experimentally elucidated the material removal mechanism of CMCs during the scratching process under the influence of vertical vibration.The results indicate that the introduction of ultrasonic vibration causes a strain rate effect,resulting in a modification of the material removal mechanism,subsequently impacting the processing quality.Ultrasonic vibration increases the dynamic strength and brittleness of the fibers in CMCs,leading to more cracks at fracture,which changes from the original bending fracture to shear fracture.In addition,ultrasonic vibration can effectively inhibit the impact of scratching depth and anisotropy on the removal mechanism of CMCs,resulting in a more uniform surface of CMCs after processing.展开更多
Standardization is necessary for the early industrialization of the new materials and technology.It is achieved by having agreed practices for the measurement of properties and other characteristics.The promising use ...Standardization is necessary for the early industrialization of the new materials and technology.It is achieved by having agreed practices for the measurement of properties and other characteristics.The promising use of graphene-based materials in fields like electronics,energy,and composites has resulted in standards for their nomenclature,the measurement of key characteristics,and their specification,etc.Among these,standards for measuring the key characteristics are crucial.The critical parameters are the number of layers,the type and concentration of defects and functional groups,elemental composition,sheet resistance,and carrier mobility.Standards for characterizing these have been analyzed by the International Organization for Standardization Technical Committee in ISO/TC229 and the International Electrotechnical Commission Technical Committee in IEC/TC113.These give details of applicable or preferred samples,the fundamental principles of the techniques,specific precautions,and points for attention in the relevant standards.The pivotal role of the ISO/TC229 and IEC/TC113 standards is considered and challenges and future trends are outlined.展开更多
CO_(2) capture and utilization(CCU)technologies have been recognized as crucial strategies for mitigating global warming,reducing carbon emission,and promoting resource circularity.As such,the design and development o...CO_(2) capture and utilization(CCU)technologies have been recognized as crucial strategies for mitigating global warming,reducing carbon emission,and promoting resource circularity.As such,the design and development of related materials have attracted considerable research attention.Carbon-based materials,characterized by tunable pore structures,abundant active sites,high specific surface area,and excellent chemical stability,demonstrate significant potential for applications in CO_(2) capture and utilization.This review systematically analyzes the adsorption behaviors and performance variations of typical carbon materials,including activated carbon,porous carbon,graphene,and carbon nanotubes during CO_(2) capture processes.Concerning CO_(2) utilization,emphasis is placed on recent advances in the catalytic applications of carbon-based materials in key reactions such as methanation,reverse water-gas shift,dry reforming of methane,and alcohol synthesis.Moreover,the benefits and drawbacks of carbon materials in terms of CO_(2) adsorption capacity,catalytic activity,and stability are thoroughly evaluated,and their potential applications in integrated CO_(2) capture and utilization technologies are discussed.Finally,key strategies for enhancing the performance of carbonaceous materials through structural modulation and surface modification are elucidated.This review aims to provide theoretical guidance for the future development and large-scale implementation of carbon-based materials in CCU technologies.展开更多
The capture of atmospheric carbon dioxide by adsorbents is an important strategy to deal with the greenhouse effect.Compared with traditional CO_(2) adsorption materials like activated carbon,silica gel,and zeolite mo...The capture of atmospheric carbon dioxide by adsorbents is an important strategy to deal with the greenhouse effect.Compared with traditional CO_(2) adsorption materials like activated carbon,silica gel,and zeolite molecular sieves,covalent organic frameworks(COFs)have excellent thermal and chemical stabilities and can be produced in many different forms.Using their different possible construction units,ordered structures for specific applications can be produced,giving them broad prospects in fields such as gas storage.This review analyzes the different types of COFs that have been synthesized and their different methods of CO_(2) capture.It then discusses different ways to increase CO_(2) adsorption by changing the internal structure of COFs and modifying their surfaces.The limitations of COF-derived carbon materials in CO_(2) capture are reviewed and,finally,the key role of machine learning and computational simulation in improving CO_(2) adsorption is mentioned,and the current status and future possible uses of COFs are summarized.展开更多
Magnesium(Mg)and its alloys have been identified as one of the most promising structural,energy and biomaterials owing to their exceptional combination of properties.These include low density,high specific strength,go...Magnesium(Mg)and its alloys have been identified as one of the most promising structural,energy and biomaterials owing to their exceptional combination of properties.These include low density,high specific strength,good damping,high castability,high capacity of hydrogen storage。展开更多
The reactive materials filled structure(RMFS)is a structural penetrator that replaces high explosive(HE)with reactive materials,presenting a novel self-distributed initiation,multiple deflagrations behavior during pen...The reactive materials filled structure(RMFS)is a structural penetrator that replaces high explosive(HE)with reactive materials,presenting a novel self-distributed initiation,multiple deflagrations behavior during penetrating multi-layered plates,and generating a multipeak overpressure behind the plates.Here analytical models of RMFS self-distributed energy release and equivalent deflagration are developed.The multipeak overpressure formation model based on the single deflagration overpressure expression was promoted.The impact tests of RMFS on multi-layered plates at 584 m/s,616 m/s,and819 m/s were performed to validate the analytical model.Further,the influence of a single overpressure peak and time intervals versus impact velocity is discussed.The analysis results indicate that the deflagration happened within 20.68 mm behind the plate,the initial impact velocity and plate thickness are the crucial factors that dominate the self-distributed multipeak overpressure effect.Three formation patterns of multipeak overpressure are proposed.展开更多
Drill string vibration during drilling plays a vital and potentially decisive role in maintaining wellbore stability,as repeated impacts may lead to fatigue and borehole collapse.While drilling through geological laye...Drill string vibration during drilling plays a vital and potentially decisive role in maintaining wellbore stability,as repeated impacts may lead to fatigue and borehole collapse.While drilling through geological layers,a material contrast may act as a localization point for wellbore damage.The hypothesis tested in this paper is that wellbore instability is focused on the boundary between the layers and that mechanical contrasts accelerate the wellbore collapse.In this study,an elastic-plastic damage model was employed to investigate the effects of repeated mechanical impacts on wellbore stability.A 2-dimensional(2D)model of a wellbore surrounded by contrasting materials was developed,and the accumulated damage caused by repeated lateral impacts was monitored.It was found that damage develops not only around the wall of the wellbore but also along the material boundaries.A sensitivity analysis was carried out to identify the impact of contrasts in both elastic(Young's modulus and Poisson's ratio)and plastic(cohesion,friction angle,and dilation angle)parameters between layers.Four damage patterns were identifiedin the simulated models.The results also suggested that the number of impacts required to reach the critical damage was highly affected by the contrast in elastic parameters,while cohesion and friction angle contrasts had a lesser effect.Additionally,increasing the contrast in the dilation angle localized the damage,thus reducing the number of impacts required to trigger wellbore failure.展开更多
Responsive colorimetric materials exhibit significant potential for application in fields such as smart food packaging and wound monitoring.The functional integration of pH-indicators with material carriers enables br...Responsive colorimetric materials exhibit significant potential for application in fields such as smart food packaging and wound monitoring.The functional integration of pH-indicators with material carriers enables breakthrough applications in nontraditional domains.In this study,we developed a novel material covalently grafted with a pH indicator that exhibited naked-eye pH-responsive color shifts.The covalent grafting of pH-responsive bromothymol blue onto carboxymethyl cellulose(CMC)was confirmed using advanced characterization techniques,including Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy.The pH-sensitive chromophore was covalently immobilized onto the CMC matrix through esterification,thereby establishing firm chemical conjugation.Moreover,a superior color-changing performance was achieved within several minutes in response to different pH values.The reusability and stability of this material offer distinct advantages over single-use pH test strips.pH-responsive colorimetric materials hold promise for efficient,noninvasive monitoring in intelligent packaging(food freshness),medical diagnostics(wound status,infections),biosensing,and environmental applications.展开更多
The mechanical performance of exceedingly soft materials such as Ag is significantly influenced by various working conditions.Therefore,this study systematically investigates the effects of crack geometry,substrate cr...The mechanical performance of exceedingly soft materials such as Ag is significantly influenced by various working conditions.Therefore,this study systematically investigates the effects of crack geometry,substrate crystal orientation,and indenter shape on crack propagation.The mechanical response of Ag is analyzed using the quasi-continuum(QC)method.A pre-crack with a predefined depth and angle was introduced to initiate fracture behavior.The results show that when the pre-crack height is 50 A,the crack propagates rapidly as the imprint depth increases from0 to 7 A,grows steadily up to 15 A,and then accelerates sharply between 15 and 20 A.For other pre-crack heights,crack propagation occurs at a relatively faster rate.Substrates with[100],[010],and[001]crystal orientations promote crack extension,while the onset of plastic deformation(referred to as the yield point in this study)and the fracture strength both increase with increasing pre-crack height.The yield point,fracture strength,and stress intensity factors are highly sensitive to the pre-crack height.When the pre-crack angle is 90○,the fracture strength reaches its maximum of 0.2%higher than that of the uncracked sample-whereas at 0○,it reaches its minimum,still 53.8%higher than that of the uncracked sample.The sample model is conducted using AutoCAD software.The optimized quasicontinuum(QC)method is used to investigate the effects of different crack geometries,substrate crystal orientations,and indenter shapes on the crack extension of Ag material.Baskes and Dow(FBD)potential is borrowed to describe the interaction forces between Ag-Ag,Ni-Ag,and Ni-Ni.展开更多
Lattice materials have demonstrated promising potential in engineering applications owing to their exceptional lightweight,high specific strength,and tunable mechanical properties.However,the traditional homogenizatio...Lattice materials have demonstrated promising potential in engineering applications owing to their exceptional lightweight,high specific strength,and tunable mechanical properties.However,the traditional homogenization methods based on the classical elasticity theory struggle to accurately describe the non-classical mechanical behaviors of lattice materials,especially when dealing with complex unit-cell geometries featured by non-symmetric configurations or non-single central node connections.In response to this limitation,this study establishes a generalized homogenization model based on the micropolar theory framework,employing Hill's boundary conditions to precisely predict the equivalent moduli of complex lattice materials.By introducing the independent rotational degree of freedom(DOF)characteristic of the micropolar theory,the proposed model successfully overcomes the limitation of conventional methods in accurately describing the asymmetric deformation and scale effects.We initially calculate the constitutive relations of two-dimensional(2D)cross-shaped multi-node chiral lattices and subsequently extend the method to three-dimensional(3D)lattices,successfully predicting the mechanical properties of both traditional and eccentric body-centered cubic(BCC)lattices.The theoretical model is validated through the finite element numerical verification which shows excellent consistency with the theoretical predictions.A further parametric study investigates the influence of geometric parameters,revealing the underlying size-effect mechanism.This paper provides a reliable theoretical tool for the design and property optimization of complex lattice materials.展开更多
Coal cinder is an abundant byproduct of the extensive consumption of coal in industrial production and daily life.Making full use of the cinder is conducive to a low-carbon economy.In this study,inspired by the burnin...Coal cinder is an abundant byproduct of the extensive consumption of coal in industrial production and daily life.Making full use of the cinder is conducive to a low-carbon economy.In this study,inspired by the burning of coal,a new method for constructing a silica-based composite porous material(SiO_(2)-CPM)was developed by combusting a siloxane-modified anthracite coal gel(CSiO_(2) gel).During this process,the combustion product was directly converted into a porous material,and the calorific value of the coal remained nearly unchanged(~98%of the original calorific value was retained),demonstrating the viability of this method for energy-efficient applications.The SiO_(2)-CPM exhibited an ultra-low thermal conductivity(0.036 W/(m·K)at room temperature),outperforming conventional insulation materials(e.g.,cotton~0.05 W/(m·K)).Additionally,it showed enhanced mechanical strength(fracture stress of 41.8 kPa)compared to the powder state of the coal cinder.Experimental results indicate that the amount of siloxane,structure-directing agent,and an acidic environment were critical for mechanical enhancement.The SiO_(2)-CPM showed good dimensional stability against thermal expansion and exhibited excellent thermal insulation and fire resistance even at 900℃.Meanwhile,the SiO_(2)-CPM with complex geometry could be easily fabricated using this method owing to the excellent shaping ability of the CSiO_(2) gel.Compared to conventional methods such as sol-gel synthesis or freeze-drying,this approach for fabricating SiO_(2)-CPM is simpler and cost-effective and allows the direct utilization of coal cinder post-combustion.展开更多
Protective hardware is essential for mitigating damage caused by unavoidable falls in humanoid robots.Despite notable progress in fall protection hardware,the theoretical foundation for modeling and the feasibility of...Protective hardware is essential for mitigating damage caused by unavoidable falls in humanoid robots.Despite notable progress in fall protection hardware,the theoretical foundation for modeling and the feasibility of conducting full-scale fall experiments on robots or their surrogates remain somewhat limited.This paper proposes a method for optimizing the thickness of Expandable Polyethylene(EPE),which is used as back protection for the Chubao humanoid robot,based on small-scale impact test data to predict full-scale behavior.The optimal thickness is defined as a balance between compact design and protective effectiveness.An equivalent impact model characterized by four parameters:contact area S,mass m,fall height h,and cushioning material thickness d is introduced to describe impact conditions.The relationship between the peak impact acceleration ap and material thickness d,which forms the core of the method and gives rise to the name AP-D,is analyzed through their plotted curves.After introducing three characteristic parameters and two correction fac-tors,the relationship among the aforementioned variables is derived.Subsequently,both the optimal thickness do and its corresponding peak impact acceleration aop are predicted via nonlinear and linear regression models.Finally,the accuracy and effectiveness of the theoretically derived optimal thickness are validated on both a dummy and the actual robot.With the cushioning material applied,the peak chest acceleration is reduced to 41.57g for the dummy and 32.08g for the robot.展开更多
As electronic technology continues to evolve towards miniaturization and integration,the demand for micro-refrigeration technology in microelectronic systems is increasing.Ferroelectric(FE)refrigeration technology bas...As electronic technology continues to evolve towards miniaturization and integration,the demand for micro-refrigeration technology in microelectronic systems is increasing.Ferroelectric(FE)refrigeration technology based on the electrocaloric effect(ECE)has emerged as a highly promising candidate in this field,due to its advantages of high energy efficiency,simple structure,easy miniaturization,low cost,and environmental friendliness.The EC performance of FE materials essentially depends on the phase transition features under the coupled electric and thermal fields,making the E–T phase diagram a core tool for decoding the underlying mechanism of ECE.This paper reviews the development of EC materials,focusing on the comprehensive study of E–T phase diagrams.By correlating the microscopic phase structure of FE materials with the macroscopic physical properties,it clarifies the manipulation mechanism for enhanced ECE performance,providing theoretical support for the targeted design of high-performance EC materials.In the future,the introduction of data-driven methods is expected to enable the high-throughput construction of FE phase diagrams,thereby accelerating the optimization of high-performance EC materials and promoting the practical application of FE refrigeration technology.展开更多
We present the first systematic experimental validation of return-current-driven cylindrical implosion scaling in micrometer-sized Cu and Al wires irradiated by J-class femtosecond laser pulses.Employing XFEL-based im...We present the first systematic experimental validation of return-current-driven cylindrical implosion scaling in micrometer-sized Cu and Al wires irradiated by J-class femtosecond laser pulses.Employing XFEL-based imaging with sub-micrometer spatial and femtosecond temporal resolution,supported by hydrodynamic and particle-in-cell simulations,we reveal how return current density depends precisely on wire diameter,material properties,and incident laser energy.We identify deviations from simple theoretical predictions due to geometrically influenced electron escape dynamics.These results refine and confirm the scaling laws essential for predictive modeling in high-energy-density physics and inertial fusion research.展开更多
Understanding the shakedown behavior of fill material is paramount to estimate the deformation stability of railway subgrade.Especially for red mudstone fill material(RMF),the noticeable overestimation of bearing capa...Understanding the shakedown behavior of fill material is paramount to estimate the deformation stability of railway subgrade.Especially for red mudstone fill material(RMF),the noticeable overestimation of bearing capacity would be encountered if the conventional strength method is used.This paper presents the shakedown analysis on RMF,with a specific emphasis on the effect of water content.A series of cyclic triaxial tests with 50,000 loading cycles was conducted.Two-stage behavior of permanent deformation and dissipated energy responses was clearly characterized,from which an energy-based criterion was proposed to determine the shakedown limits.The proposed energy-based criterion was validated by examining its performance to various geomaterials including cohesive soils and unbound granular materials(UGMs).By applying the proposed method to RMF,the S-shape evolution curve was obtained in terms of shakedown limits with initial suction.Microfabric difference was believed as the main consequence of the S-shape mode.Demonstration was confirmed by the mercury intrusion porosimetry(MIP)and scanning electron microscope(SEM)analyses.By applying the proposed method to different geomaterials,an extensive comparison was made between the shakedown limits and the static shear strength.The ratio of shakedown limits to the static shear strength for saturated RMF specimen fell within the range of soft clays,while that of unsaturated specimen lies within the range of UGMs.展开更多
Conventional ignition methods are proving to be ineffective for low-sensitivity energetic materials,highlighting the need to investigate alternative ignition systems,such as laser-based techniques.Over the past decade...Conventional ignition methods are proving to be ineffective for low-sensitivity energetic materials,highlighting the need to investigate alternative ignition systems,such as laser-based techniques.Over the past decade,lasers have emerged as a promising solution,providing focused energy beams for controllable,efficient,and reliable ignition in the field of energetic materials.This study presents a comparative analysis of two state-of-the-art ignition approaches:direct laser ignition and laser-driven flyer ignition.Experiments were performed using a Neodymium-doped Yttrium Aluminum Garnet(Nd:YAG)laser at different energy beam levels to systematically evaluate ignition onset.In the direct laser ignition test setup,the laser beam was applied directly to the energetic tested material,while laserdriven flyer ignition utilized 40 and 100μm aluminum foils,propelled at velocities ranging from 300 to 1250 m/s.Comparative analysis with the Lawrence and Trott model substantiated the velocity data and provided insight into the ignition mechanisms.Experimental results indicate that the ignition time for the laser-driven flyer method was significantly shorter,with the pyrotechnic composition achieving complete combustion faster compared to direct laser ignition.Moreover,precise ignition thresholds were determined for both methods,providing critical parameters for optimizing ignition systems in energetic materials.This work elucidates the advantages and limitations of each technique while advancing next-generation ignition technology,enhancing the reliability and safety of propulsion systems.展开更多
基金supported by the National Natural Science Foundation of China(52305388,BE0200030)Shanghai Pujiang Program(22PJ1407600)+1 种基金SJTU Explore X programShanghai Jiao Tong University Initiative Scientific Research Program(WH220402021)。
文摘Moisture electricity generation(MEG)has emerged as a sustainable and versatile energy-harvesting technology capable of converting ubiquitous environmental moisture into electrical energy,which holds great promise for renewable energy and constructing self-powered electronics.In this review,we begin by outlining the fundamental mechanisms—ion diffusion,electric double layer formation,and streaming potential—that govern charge transport for MEG in moist environments.A comprehensive survey of material innovations follows,highlighting breakthroughs in carbon-based materials,conductive polymers,hydrogels,and bio-inspired systems that enhance MEG performance,scalability,and biocompatibility.We then explore a range of device architectures,from planar and layered systems to flexible,miniaturized,and textile-integrated designs,engineered for both energy conversion and sensor integration.Key challenges are analyzed,along with strategies for overcoming them.We conclude with a forward-looking perspective on future directions,including hybrid energy systems,AI-assisted material design,and real-world deployment.This review presents a timely and comprehensive overview of MEG technologies and their trajectory toward practical and sustainable energy solutions.
文摘Investments in eco-friendly,recyclable material solutions and innovation in bio-based nonwovens are increasingly shaping the next generation of automotive interiors.The development of nonwoven materials and associated technologies is likely to lead to even wider adoption in the automotive industry,driven by rising global vehicle production,particularly in the growing electric vehicle(EV)segment,and an intensified focus on sustainable solutions.
文摘In the context of diminishing energy resources and worsening greenhouse effect,thermoelectric materials have great potential for sustainable development due to their green and environmentally friendly characteristics.Among inorganic thermoelectric materials,copper sulfide compounds have greater potential than others due to their abundant element reserves on Earth,lower usage costs,non-toxicity,and good biocompatibility.Compared to organic thermoelectric materials,the"phonon liquid-electron crystal"(PLEC)feature of copper sulfide compounds makes them have stronger thermoelectric performance.This review summarizes the latest research progress in the synthesis methods and thermoelectric modification strategies of copper sulfide compounds.It first explains the importance of the solid-phase method in the manufacture of thermoelectric devices,and then focuses on the great potential of nanoscale synthesis technology based on liquid-phase method in the preparation of thermoelectric materials.Finally,it systematically discusses several strategies for regulating the thermoelectric performance of copper sulfide compounds,including adjusting the chemical proportion of Cu_(2-x)S and introducing element doping to regulate the crystal structure,phase composition,chemical composition,band structure,and nanoscale microstructure of copper sulfide compounds,and directly affecting ZT value by adjusting conductivity and thermal conductivity.In addition,it discusses composite engineering based on copper sulfide compounds,including inorganic,organic,and metal compounds,and discusses tri-component compounds derived from sulfide copper.Finally,it discusses the main challenges and prospects of the development of copper sulfide-based thermoelectric materials,hoping that this review will promote the development of copper sulfide-based thermoelectric materials.
基金supported by the National Science Foundation for Distinguished Young Scholars of China(No.52325506)the Fundamental Research Funds for the Central Universities(No.DUT22LAB501)。
文摘Ultrasonic-Assisted Grinding(UAG)is a novel manufacturing technology that shows promising promise for use in processing Ceramic Matrix Composites(CMCs).Nevertheless,analyzing the material removal process of CMCs with multidirectional structure during UAG is challenging,impeding the progress and improvement of the UAG process.This work examined the impact of ultrasonic vibration on the dynamic mechanical characteristics during processing.Additionally,we experimentally elucidated the material removal mechanism of CMCs during the scratching process under the influence of vertical vibration.The results indicate that the introduction of ultrasonic vibration causes a strain rate effect,resulting in a modification of the material removal mechanism,subsequently impacting the processing quality.Ultrasonic vibration increases the dynamic strength and brittleness of the fibers in CMCs,leading to more cracks at fracture,which changes from the original bending fracture to shear fracture.In addition,ultrasonic vibration can effectively inhibit the impact of scratching depth and anisotropy on the removal mechanism of CMCs,resulting in a more uniform surface of CMCs after processing.
文摘Standardization is necessary for the early industrialization of the new materials and technology.It is achieved by having agreed practices for the measurement of properties and other characteristics.The promising use of graphene-based materials in fields like electronics,energy,and composites has resulted in standards for their nomenclature,the measurement of key characteristics,and their specification,etc.Among these,standards for measuring the key characteristics are crucial.The critical parameters are the number of layers,the type and concentration of defects and functional groups,elemental composition,sheet resistance,and carrier mobility.Standards for characterizing these have been analyzed by the International Organization for Standardization Technical Committee in ISO/TC229 and the International Electrotechnical Commission Technical Committee in IEC/TC113.These give details of applicable or preferred samples,the fundamental principles of the techniques,specific precautions,and points for attention in the relevant standards.The pivotal role of the ISO/TC229 and IEC/TC113 standards is considered and challenges and future trends are outlined.
基金Supported by National Key R&D Program of China(2025YFE0109700)the National Natural Science Foundation of China(52106150)。
文摘CO_(2) capture and utilization(CCU)technologies have been recognized as crucial strategies for mitigating global warming,reducing carbon emission,and promoting resource circularity.As such,the design and development of related materials have attracted considerable research attention.Carbon-based materials,characterized by tunable pore structures,abundant active sites,high specific surface area,and excellent chemical stability,demonstrate significant potential for applications in CO_(2) capture and utilization.This review systematically analyzes the adsorption behaviors and performance variations of typical carbon materials,including activated carbon,porous carbon,graphene,and carbon nanotubes during CO_(2) capture processes.Concerning CO_(2) utilization,emphasis is placed on recent advances in the catalytic applications of carbon-based materials in key reactions such as methanation,reverse water-gas shift,dry reforming of methane,and alcohol synthesis.Moreover,the benefits and drawbacks of carbon materials in terms of CO_(2) adsorption capacity,catalytic activity,and stability are thoroughly evaluated,and their potential applications in integrated CO_(2) capture and utilization technologies are discussed.Finally,key strategies for enhancing the performance of carbonaceous materials through structural modulation and surface modification are elucidated.This review aims to provide theoretical guidance for the future development and large-scale implementation of carbon-based materials in CCU technologies.
文摘The capture of atmospheric carbon dioxide by adsorbents is an important strategy to deal with the greenhouse effect.Compared with traditional CO_(2) adsorption materials like activated carbon,silica gel,and zeolite molecular sieves,covalent organic frameworks(COFs)have excellent thermal and chemical stabilities and can be produced in many different forms.Using their different possible construction units,ordered structures for specific applications can be produced,giving them broad prospects in fields such as gas storage.This review analyzes the different types of COFs that have been synthesized and their different methods of CO_(2) capture.It then discusses different ways to increase CO_(2) adsorption by changing the internal structure of COFs and modifying their surfaces.The limitations of COF-derived carbon materials in CO_(2) capture are reviewed and,finally,the key role of machine learning and computational simulation in improving CO_(2) adsorption is mentioned,and the current status and future possible uses of COFs are summarized.
文摘Magnesium(Mg)and its alloys have been identified as one of the most promising structural,energy and biomaterials owing to their exceptional combination of properties.These include low density,high specific strength,good damping,high castability,high capacity of hydrogen storage。
基金the support received from the National Natural Science Foundation of China(Grant No.12302460)the State Key Laboratory of Explosion Science and Safety Protection(Grant No.YBKT24-02)。
文摘The reactive materials filled structure(RMFS)is a structural penetrator that replaces high explosive(HE)with reactive materials,presenting a novel self-distributed initiation,multiple deflagrations behavior during penetrating multi-layered plates,and generating a multipeak overpressure behind the plates.Here analytical models of RMFS self-distributed energy release and equivalent deflagration are developed.The multipeak overpressure formation model based on the single deflagration overpressure expression was promoted.The impact tests of RMFS on multi-layered plates at 584 m/s,616 m/s,and819 m/s were performed to validate the analytical model.Further,the influence of a single overpressure peak and time intervals versus impact velocity is discussed.The analysis results indicate that the deflagration happened within 20.68 mm behind the plate,the initial impact velocity and plate thickness are the crucial factors that dominate the self-distributed multipeak overpressure effect.Three formation patterns of multipeak overpressure are proposed.
基金support from the Research Council of Norway,Equinor,and Sekal with NFR project(Grant No.308826).
文摘Drill string vibration during drilling plays a vital and potentially decisive role in maintaining wellbore stability,as repeated impacts may lead to fatigue and borehole collapse.While drilling through geological layers,a material contrast may act as a localization point for wellbore damage.The hypothesis tested in this paper is that wellbore instability is focused on the boundary between the layers and that mechanical contrasts accelerate the wellbore collapse.In this study,an elastic-plastic damage model was employed to investigate the effects of repeated mechanical impacts on wellbore stability.A 2-dimensional(2D)model of a wellbore surrounded by contrasting materials was developed,and the accumulated damage caused by repeated lateral impacts was monitored.It was found that damage develops not only around the wall of the wellbore but also along the material boundaries.A sensitivity analysis was carried out to identify the impact of contrasts in both elastic(Young's modulus and Poisson's ratio)and plastic(cohesion,friction angle,and dilation angle)parameters between layers.Four damage patterns were identifiedin the simulated models.The results also suggested that the number of impacts required to reach the critical damage was highly affected by the contrast in elastic parameters,while cohesion and friction angle contrasts had a lesser effect.Additionally,increasing the contrast in the dilation angle localized the damage,thus reducing the number of impacts required to trigger wellbore failure.
基金financially supported by the National Natural Science Foundation of China(No.52303209)the“Lingyan”Program of Zhejiang Province(No.2024C03076)+1 种基金Zhejiang University K.P.Chao’s High Technology Development Foundationthe generous support provided by the joint research fund from the Shaoxing Institute of Zhejiang University and Shaoxing Maternity and Child Health Care Hospital。
文摘Responsive colorimetric materials exhibit significant potential for application in fields such as smart food packaging and wound monitoring.The functional integration of pH-indicators with material carriers enables breakthrough applications in nontraditional domains.In this study,we developed a novel material covalently grafted with a pH indicator that exhibited naked-eye pH-responsive color shifts.The covalent grafting of pH-responsive bromothymol blue onto carboxymethyl cellulose(CMC)was confirmed using advanced characterization techniques,including Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy.The pH-sensitive chromophore was covalently immobilized onto the CMC matrix through esterification,thereby establishing firm chemical conjugation.Moreover,a superior color-changing performance was achieved within several minutes in response to different pH values.The reusability and stability of this material offer distinct advantages over single-use pH test strips.pH-responsive colorimetric materials hold promise for efficient,noninvasive monitoring in intelligent packaging(food freshness),medical diagnostics(wound status,infections),biosensing,and environmental applications.
基金by the Industry–Academia Cooperation Project No.113A00262(Te-Hua Fang).URLs to the sponsor websites are available at:https://www.nstc.gov.tw.
文摘The mechanical performance of exceedingly soft materials such as Ag is significantly influenced by various working conditions.Therefore,this study systematically investigates the effects of crack geometry,substrate crystal orientation,and indenter shape on crack propagation.The mechanical response of Ag is analyzed using the quasi-continuum(QC)method.A pre-crack with a predefined depth and angle was introduced to initiate fracture behavior.The results show that when the pre-crack height is 50 A,the crack propagates rapidly as the imprint depth increases from0 to 7 A,grows steadily up to 15 A,and then accelerates sharply between 15 and 20 A.For other pre-crack heights,crack propagation occurs at a relatively faster rate.Substrates with[100],[010],and[001]crystal orientations promote crack extension,while the onset of plastic deformation(referred to as the yield point in this study)and the fracture strength both increase with increasing pre-crack height.The yield point,fracture strength,and stress intensity factors are highly sensitive to the pre-crack height.When the pre-crack angle is 90○,the fracture strength reaches its maximum of 0.2%higher than that of the uncracked sample-whereas at 0○,it reaches its minimum,still 53.8%higher than that of the uncracked sample.The sample model is conducted using AutoCAD software.The optimized quasicontinuum(QC)method is used to investigate the effects of different crack geometries,substrate crystal orientations,and indenter shapes on the crack extension of Ag material.Baskes and Dow(FBD)potential is borrowed to describe the interaction forces between Ag-Ag,Ni-Ag,and Ni-Ni.
基金Project supported by the National Natural Science Foundation of China(No.12472077)the supports from Shanghai Gaofeng Project for University Academic Program Development,Fundamental Research Funds for the Central Universities(No.22120240353).
文摘Lattice materials have demonstrated promising potential in engineering applications owing to their exceptional lightweight,high specific strength,and tunable mechanical properties.However,the traditional homogenization methods based on the classical elasticity theory struggle to accurately describe the non-classical mechanical behaviors of lattice materials,especially when dealing with complex unit-cell geometries featured by non-symmetric configurations or non-single central node connections.In response to this limitation,this study establishes a generalized homogenization model based on the micropolar theory framework,employing Hill's boundary conditions to precisely predict the equivalent moduli of complex lattice materials.By introducing the independent rotational degree of freedom(DOF)characteristic of the micropolar theory,the proposed model successfully overcomes the limitation of conventional methods in accurately describing the asymmetric deformation and scale effects.We initially calculate the constitutive relations of two-dimensional(2D)cross-shaped multi-node chiral lattices and subsequently extend the method to three-dimensional(3D)lattices,successfully predicting the mechanical properties of both traditional and eccentric body-centered cubic(BCC)lattices.The theoretical model is validated through the finite element numerical verification which shows excellent consistency with the theoretical predictions.A further parametric study investigates the influence of geometric parameters,revealing the underlying size-effect mechanism.This paper provides a reliable theoretical tool for the design and property optimization of complex lattice materials.
基金supported by the National Natural Science Foundation of China(No.52573220)the National Key R&D Program of China(No.2023YFC3404201)+1 种基金the Fundamental Research Funds for the Central Universities(No.FRF-IDRY-GD24-005)the State Key Laboratory of Solid Waste Reuse for Building Materials(No.SWR-2022-009).
文摘Coal cinder is an abundant byproduct of the extensive consumption of coal in industrial production and daily life.Making full use of the cinder is conducive to a low-carbon economy.In this study,inspired by the burning of coal,a new method for constructing a silica-based composite porous material(SiO_(2)-CPM)was developed by combusting a siloxane-modified anthracite coal gel(CSiO_(2) gel).During this process,the combustion product was directly converted into a porous material,and the calorific value of the coal remained nearly unchanged(~98%of the original calorific value was retained),demonstrating the viability of this method for energy-efficient applications.The SiO_(2)-CPM exhibited an ultra-low thermal conductivity(0.036 W/(m·K)at room temperature),outperforming conventional insulation materials(e.g.,cotton~0.05 W/(m·K)).Additionally,it showed enhanced mechanical strength(fracture stress of 41.8 kPa)compared to the powder state of the coal cinder.Experimental results indicate that the amount of siloxane,structure-directing agent,and an acidic environment were critical for mechanical enhancement.The SiO_(2)-CPM showed good dimensional stability against thermal expansion and exhibited excellent thermal insulation and fire resistance even at 900℃.Meanwhile,the SiO_(2)-CPM with complex geometry could be easily fabricated using this method owing to the excellent shaping ability of the CSiO_(2) gel.Compared to conventional methods such as sol-gel synthesis or freeze-drying,this approach for fabricating SiO_(2)-CPM is simpler and cost-effective and allows the direct utilization of coal cinder post-combustion.
基金Natural Science Foundation of Beijing Municipality under Grant L243004the National Natural Science Foundation of China under Grant 62403060.
文摘Protective hardware is essential for mitigating damage caused by unavoidable falls in humanoid robots.Despite notable progress in fall protection hardware,the theoretical foundation for modeling and the feasibility of conducting full-scale fall experiments on robots or their surrogates remain somewhat limited.This paper proposes a method for optimizing the thickness of Expandable Polyethylene(EPE),which is used as back protection for the Chubao humanoid robot,based on small-scale impact test data to predict full-scale behavior.The optimal thickness is defined as a balance between compact design and protective effectiveness.An equivalent impact model characterized by four parameters:contact area S,mass m,fall height h,and cushioning material thickness d is introduced to describe impact conditions.The relationship between the peak impact acceleration ap and material thickness d,which forms the core of the method and gives rise to the name AP-D,is analyzed through their plotted curves.After introducing three characteristic parameters and two correction fac-tors,the relationship among the aforementioned variables is derived.Subsequently,both the optimal thickness do and its corresponding peak impact acceleration aop are predicted via nonlinear and linear regression models.Finally,the accuracy and effectiveness of the theoretically derived optimal thickness are validated on both a dummy and the actual robot.With the cushioning material applied,the peak chest acceleration is reduced to 41.57g for the dummy and 32.08g for the robot.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.U25A20232,52325208,52173217,52202128)the Interdisciplinary Research Project for Young Teachers of USTB(Grant No.FRF-IDRY24-002)。
文摘As electronic technology continues to evolve towards miniaturization and integration,the demand for micro-refrigeration technology in microelectronic systems is increasing.Ferroelectric(FE)refrigeration technology based on the electrocaloric effect(ECE)has emerged as a highly promising candidate in this field,due to its advantages of high energy efficiency,simple structure,easy miniaturization,low cost,and environmental friendliness.The EC performance of FE materials essentially depends on the phase transition features under the coupled electric and thermal fields,making the E–T phase diagram a core tool for decoding the underlying mechanism of ECE.This paper reviews the development of EC materials,focusing on the comprehensive study of E–T phase diagrams.By correlating the microscopic phase structure of FE materials with the macroscopic physical properties,it clarifies the manipulation mechanism for enhanced ECE performance,providing theoretical support for the targeted design of high-performance EC materials.In the future,the introduction of data-driven methods is expected to enable the high-throughput construction of FE phase diagrams,thereby accelerating the optimization of high-performance EC materials and promoting the practical application of FE refrigeration technology.
基金partially supported by the Center for Advanced Systems Understanding(CASUS)financed by Germany’s Federal Ministry of Education and Research(BMBF)+2 种基金the Saxon State Government out of the State Budget approved by the Saxon State Parliamentfunding from the European Union’s Just Transition Fund(JTF)within the project Röntgenlaser-Optimierung der Laserfusion(ROLF),Contract No.5086999001co-financed by the Saxon State Government out of the State Budget approved by the Saxon State Parliament.
文摘We present the first systematic experimental validation of return-current-driven cylindrical implosion scaling in micrometer-sized Cu and Al wires irradiated by J-class femtosecond laser pulses.Employing XFEL-based imaging with sub-micrometer spatial and femtosecond temporal resolution,supported by hydrodynamic and particle-in-cell simulations,we reveal how return current density depends precisely on wire diameter,material properties,and incident laser energy.We identify deviations from simple theoretical predictions due to geometrically influenced electron escape dynamics.These results refine and confirm the scaling laws essential for predictive modeling in high-energy-density physics and inertial fusion research.
基金support from the National Natural Science Foundation of China(Grant Nos.52278432 and 52478475)the Science and Technology Research and Development Plan of China National Railway Group Co.,Ltd.(Grant No.K2023G033)were greatly appreciated.
文摘Understanding the shakedown behavior of fill material is paramount to estimate the deformation stability of railway subgrade.Especially for red mudstone fill material(RMF),the noticeable overestimation of bearing capacity would be encountered if the conventional strength method is used.This paper presents the shakedown analysis on RMF,with a specific emphasis on the effect of water content.A series of cyclic triaxial tests with 50,000 loading cycles was conducted.Two-stage behavior of permanent deformation and dissipated energy responses was clearly characterized,from which an energy-based criterion was proposed to determine the shakedown limits.The proposed energy-based criterion was validated by examining its performance to various geomaterials including cohesive soils and unbound granular materials(UGMs).By applying the proposed method to RMF,the S-shape evolution curve was obtained in terms of shakedown limits with initial suction.Microfabric difference was believed as the main consequence of the S-shape mode.Demonstration was confirmed by the mercury intrusion porosimetry(MIP)and scanning electron microscope(SEM)analyses.By applying the proposed method to different geomaterials,an extensive comparison was made between the shakedown limits and the static shear strength.The ratio of shakedown limits to the static shear strength for saturated RMF specimen fell within the range of soft clays,while that of unsaturated specimen lies within the range of UGMs.
文摘Conventional ignition methods are proving to be ineffective for low-sensitivity energetic materials,highlighting the need to investigate alternative ignition systems,such as laser-based techniques.Over the past decade,lasers have emerged as a promising solution,providing focused energy beams for controllable,efficient,and reliable ignition in the field of energetic materials.This study presents a comparative analysis of two state-of-the-art ignition approaches:direct laser ignition and laser-driven flyer ignition.Experiments were performed using a Neodymium-doped Yttrium Aluminum Garnet(Nd:YAG)laser at different energy beam levels to systematically evaluate ignition onset.In the direct laser ignition test setup,the laser beam was applied directly to the energetic tested material,while laserdriven flyer ignition utilized 40 and 100μm aluminum foils,propelled at velocities ranging from 300 to 1250 m/s.Comparative analysis with the Lawrence and Trott model substantiated the velocity data and provided insight into the ignition mechanisms.Experimental results indicate that the ignition time for the laser-driven flyer method was significantly shorter,with the pyrotechnic composition achieving complete combustion faster compared to direct laser ignition.Moreover,precise ignition thresholds were determined for both methods,providing critical parameters for optimizing ignition systems in energetic materials.This work elucidates the advantages and limitations of each technique while advancing next-generation ignition technology,enhancing the reliability and safety of propulsion systems.
