期刊文献+
共找到554篇文章
< 1 2 28 >
每页显示 20 50 100
A review of the standardized measurement of the characteristics of graphene-based materials
1
作者 Zhang Donghui Li Wan +2 位作者 Ou Bingxian Wang Liangwang Ge Guanglu 《新型炭材料(中英文)》 北大核心 2026年第1期91-108,共18页
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
关键词 Nanotechnology Graphene-based materials Measurement standards Critical characteristics Quality control
在线阅读 下载PDF
Broadband high-extinction-ratio nonvolatile optical switch based on phase change material
2
作者 LIANG Kai YUE Wen-Cheng +4 位作者 XU Fan ZHU Qian-Nan ZHANG Jian-Min WANG Shu-Xiao CAI Yan 《红外与毫米波学报》 北大核心 2026年第1期36-41,共6页
In this paper,we present a broadband,high-extinction-ratio,nonvolatile 2×2 Mach-Zehnder interfer⁃ometer(MZI)optical switch based on the phase change material Sb_(2)Se_(3).The insertion loss(IL)is 0.84 dB and the ... In this paper,we present a broadband,high-extinction-ratio,nonvolatile 2×2 Mach-Zehnder interfer⁃ometer(MZI)optical switch based on the phase change material Sb_(2)Se_(3).The insertion loss(IL)is 0.84 dB and the extinction ratio(ER)reaches 28.8 dB at the wavelength of 1550 nm.The 3 dB bandwidth is greater than 150 nm.Within the 3 dB bandwidth,the ER is greater than 20.3 dB and 16.3 dB at bar and cross states,respectively.The power consumption for crystallization and amorphization of Sb_(2)Se_(3) is 105.86 nJ and 49 nJ,respectively.The switch holds significant promise for optical interconnects and optical computing applications. 展开更多
关键词 photonic integration optical switch phase change materials
在线阅读 下载PDF
Recent advances in carbon-based materials for CO_(2) capture and utilization
3
作者 FU Lang YAO Dingding +2 位作者 HU Qiang YAN Shuiping YANG Haiping 《燃料化学学报(中英文)》 北大核心 2026年第3期15-32,共18页
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
关键词 CO_(2)capture and utilization carbon materials ADSORPTION CATALYSIS
在线阅读 下载PDF
A review of covalent organic framework materials for CO_(2) adsorption
4
作者 Zeng Fanqiang Ji Changchun +1 位作者 Wang Yudong Li Yousheng 《新型炭材料(中英文)》 北大核心 2026年第1期44-66,共23页
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
关键词 CO_(2)capture Modification of COFs COF-derived carbon materials Machine learning Computational simulation
在线阅读 下载PDF
Study on the reactive material filled structure under impact loading:The self-distributed multipeak overpressure effect
5
作者 Jing'an Xiang Haifu Wang +2 位作者 Yueguang Yan Aoxin Liu Chao Ge 《Defence Technology(防务技术)》 2026年第1期193-209,共17页
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
关键词 Reactive material Impact Self-distributed OVERPRESSURE Multipeak
在线阅读 下载PDF
Advancing ignition techniques for energetic materials:A comparative study of direct laser ignition and laser-driven flyer methods
6
作者 Razvan-Marian Mircioaga Baptiste Reynier +4 位作者 Tudor Prisecaru Adrian-Nicolae Rotariu Florin-Marian Dîrloman Liviu-Cristian Matache Laviniu Haller 《Defence Technology(防务技术)》 2026年第1期180-192,共13页
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
关键词 Energetic material Laser ignition Laser-driven flyer ignition High-velocity impact Laser fluence
在线阅读 下载PDF
Dynamic fracture behavior and coupled impact effect of as-cast W-Zr-Ti energetic structural material
7
作者 Yuxuan Qi Liang Mao +3 位作者 Chunlan Jiang Guitao Liu Kongxun Zhao Mengchen Zhang 《Defence Technology(防务技术)》 2026年第1期422-435,共14页
This paper prepared a novel as-cast W-Zr-Ti metallic ESM using high-frequency vacuum induction melting technique.The above ESM performs a typical elastic-brittle material feature and strain rate strengthening behavior... This paper prepared a novel as-cast W-Zr-Ti metallic ESM using high-frequency vacuum induction melting technique.The above ESM performs a typical elastic-brittle material feature and strain rate strengthening behavior.The specimens exhibit violent chemical reaction during the fracture process under the impact loading,and the size distribution of their residual debris follows Rosin-Rammler model.The dynamic fracture toughness is obtained by the fitting of debris length scale,approximately 1.87 MPa·m~(1/2).Microstructure observation on residual debris indicates that the failure process is determined by primary crack propagation under quasi-static compression,while it is affected by multiple cracks propagation in both particle and matrix in the case of dynamic impact.Impact test demonstrates that the novel energetic fragment performs brilliant penetration and combustion effect behind the front target,leading to the effective ignition of fuel tank.For the brittleness of as-cast W-ZrTi ESM,further study conducted bond-based peridynamic(BB-PD)C++computational code to simulate its fracture behavior during penetration.The BB-PD method successfully captured the fracture process and debris cloud formation of the energetic fragment.This paper explores a novel as-cast metallic ESM,and provides an available numerical avenue to the simulation of brittle energetic fragment. 展开更多
关键词 Energetic structural material Dynamic fracture behavior Coupled impact effect Mechanical property Peridynamics As-cast W-Zr-Ti alloy
在线阅读 下载PDF
ReacNetwork: A method for large-scale reaction network analysis of energetic materials
8
作者 Zhonghui Chen Chengjie Tong +5 位作者 Qiang Gan Jie Li Yuhang Tao Gen Li Yajun Wang Changgen Feng 《Defence Technology(防务技术)》 2026年第3期202-216,共15页
The combustion and detonation processes of energetic materials exhibit remarkable complexity and ultra-fast transient characteristics.While reactive molecular dynamics has been extensively employed to investigate the ... The combustion and detonation processes of energetic materials exhibit remarkable complexity and ultra-fast transient characteristics.While reactive molecular dynamics has been extensively employed to investigate the reaction dynamics of energetic materials,its utility is often constrained to capturing only fundamental reaction events and species information,thereby limiting mechanistic investigations of complex reaction pathways.To elucidate the topological features of energetic material reaction networks and identify critical reaction pathways with high fidelity,this study presents ReacNetwork-an advanced large-scale reaction network analysis methodology that synergistically integrates complex network theory with molecular simulation techniques.Specifically,we have developed a multi-dimensional feature screening protocol based on node centrality metrics and K-shell decomposition algorithms.Takingα-Hexahydro-1,3,5-trinitro-1,3,5-triazine(α-RDX)as the subject,we successfully constructed a comprehensive high-temperature thermal decomposition reaction network consisting of 1,134 distinct chemical species and 3,626 elementary reactions.Through systematic application of community detection algorithms and global topological feature extraction techniques,we achieved effective dimensionality reduction and successfully identified the dominant reaction pathway within theα-RDX thermal decomposition network.The computational results not only validate the well-established initial reaction mechanism dominated by N-NO2 homolytic bond cleavage,but also provide unprecedented visualization ofα-RDX framework ring-opening dynamics and subsequent radical chain propagation networks. 展开更多
关键词 Energetic materials RDX reaction network Multi-dimensional feature screening Network dimensionality reduction and analysis
在线阅读 下载PDF
Ultra heat-resistant hydrogen-bonded organic framework:Breaking the thermal stability limit of high-energy materials
9
作者 Bojun Tan Jinkang Dou +13 位作者 Jing Zhang Xiong Yang Jiatong Ren Changwei Tang Jian Su Gen Zhang Siwei Song Qinghua Zhang Binghui Duan Hongchang Mo Minghui Xu Xianming Lu Bozhou Wang Ning Liu 《Defence Technology(防务技术)》 2026年第3期300-306,共7页
The pursuit of heat-resistant energetic materials(HREMs)with thermal stability beyond 450℃ presents a significant challenge that has yet to be achieved.In this work,we develop an innovative electronic delocalization ... The pursuit of heat-resistant energetic materials(HREMs)with thermal stability beyond 450℃ presents a significant challenge that has yet to be achieved.In this work,we develop an innovative electronic delocalization strategy to design and synthesize a planar dizwitterionic diamino-bistriazolotetrazine,designated as TYX-1.The unique structural feature of TYX-1,including a nitrogen-rich fused ring system,planar conformation,and dizwitterionic configuration,combined with its hydrogen-bonded organic framework(HOF)structure,confer exceptional thermal stability(The onset temperature is 428℃,and the peak temperature is 473℃),high density(1.84 g/cm^(3)),and remarkable detonation performance(detonation velocity:8616 m/s).Furthermore,TYX-1 exhibits an impressive insensitivity(impact sensitivity>40 J;friction sensitivity>360 N),surpassing all previously reported HREMs.Theoretical calculations and single-crystal clearly indicate that the delocalizedπelectrons within the dizwitterionic bistriazolotetrazine rings and the HOF structure of TYX-1 are pivotal in ensuring its high thermal stability and high energy density.The discovery of TYX-1 marks a significant advancement in the field of HREMs and is anticipated to catalyze substantial progress in various high-temperature applications reliant on energetic materials. 展开更多
关键词 Ultra heat-resistant energetic materials Hydrogen-bonded organic framework A planar dizwitterionic structure Nitrogen-rich fused-ring skeleton
在线阅读 下载PDF
A review of carbon-based hybrid materials for supercapacitors 被引量:4
10
作者 Theodore Azemtsop Manfo Hannu Laaksonen 《新型炭材料(中英文)》 北大核心 2025年第1期81-110,共30页
Supercapacitors are gaining popularity due to their high cycling stability,power density,and fast charge and discharge rates.Researchers are ex-ploring electrode materials,electrolytes,and separat-ors for cost-effecti... Supercapacitors are gaining popularity due to their high cycling stability,power density,and fast charge and discharge rates.Researchers are ex-ploring electrode materials,electrolytes,and separat-ors for cost-effective energy storage systems.Ad-vances in materials science have led to the develop-ment of hybrid nanomaterials,such as combining fil-amentous carbon forms with inorganic nanoparticles,to create new charge and energy transfer processes.Notable materials for electrochemical energy-stor-age applications include MXenes,2D transition met-al carbides,and nitrides,carbon black,carbon aerogels,activated carbon,carbon nanotubes,conducting polymers,carbon fibers,and nanofibers,and graphene,because of their thermal,electrical,and mechanical properties.Carbon materials mixed with conducting polymers,ceramics,metal oxides,transition metal oxides,metal hydroxides,transition metal sulfides,trans-ition metal dichalcogenide,metal sulfides,carbides,nitrides,and biomass materials have received widespread attention due to their remarkable performance,eco-friendliness,cost-effectiveness,and renewability.This article explores the development of carbon-based hybrid materials for future supercapacitors,including electric double-layer capacitors,pseudocapacitors,and hy-brid supercapacitors.It investigates the difficulties that influence structural design,manufacturing(electrospinning,hydro-thermal/solvothermal,template-assisted synthesis,electrodeposition,electrospray,3D printing)techniques and the latest car-bon-based hybrid materials research offer practical solutions for producing high-performance,next-generation supercapacitors. 展开更多
关键词 Carbon-based hybrid material Structure design Electrode material Specific capacitance SUPERCAPACITORS
在线阅读 下载PDF
Progress in the Binding of Chloride Ions in Cement-based Materials
11
作者 DU Xixian LI Gang +2 位作者 WANG Aiqin CAO Aoli SUN Jianren 《材料导报》 北大核心 2025年第13期100-113,共14页
Chloride ions(Cl^(-))have been shown to impact the long-lasting nature of reinforced concrete.However,Cl^(-)that are already bound inside the concrete will not lead to the deterioration of the concrete’s characterist... Chloride ions(Cl^(-))have been shown to impact the long-lasting nature of reinforced concrete.However,Cl^(-)that are already bound inside the concrete will not lead to the deterioration of the concrete’s characteristics.The composition of the cement-based material,including the type of cement and auxiliary materials,greatly influences the ability of the material to bind Cl^(-),and varied components result in varying binding beha-vior of the Cl^(-).Simultaneously,the Cl^(-)binding process in concrete is influenced by both the internal and exterior surroundings,as well as the curing practices.These factors impact the hydration process of the cement and the internal pore structure of the concrete.Currently,mathematical theories and molecular dynamics simulations have increasingly been employed as the prevalent methods for examining the binding behaviors of Cl^(-)in concrete.These techniques are extensively utilized for predicting the lifespan and conducting microscopic studies of reinforced concrete in Cl^(-)settings.This work proposes recommendations for future research based on a summary of experimental and simulation investigations on Cl^(-)binding.Which will offer theoretical guidance for studying the binding of Cl^(-)in cement-based materials. 展开更多
关键词 cement-based material chloride binding auxiliary material environment curing practice simulation
在线阅读 下载PDF
Corrosion resistance and modification mechanism of modified anchoring grouting material in carbonaceous mudstone environment
12
作者 QIU Xiang YIN Qian +5 位作者 XU Hong LI Yao CHEN Jing-cheng WU Yong XIA Xie-hui FU Si-ni 《Journal of Central South University》 2025年第11期4486-4499,共14页
In the corrosive environment of carbonaceous mudstone,the mechanical properties of grouting materials in the anchorage section of anchor bolts continue to deteriorate.In response,a cement-based modified anchoring grou... In the corrosive environment of carbonaceous mudstone,the mechanical properties of grouting materials in the anchorage section of anchor bolts continue to deteriorate.In response,a cement-based modified anchoring grouting material(MAGM)with high corrosion resistance was developed.The results reveal that compared with those of ordinary Portland cement(OPC)grouting material,the compressive strength,tensile strength,and shear stress peak of the MAGM increased by 85.9%,44.4%and 45.4%,respectively,after 28 d of corrosion in a carbonaceous mudstone solution.Waterborne epoxy resin and curing agent create a network membrane structure under the action of nano-Al_(2)O_(3)to protect the cement hydration products.In the corrosive environment of carbonaceous mudstone,corrosion products formed on the surface of the stone body have adsorbed onto the reticular membrane structure,filling the pores of the stone body and slowing the erosion rate of ions.After 365 d of application of MAGM and OPC in the corrosive environment of a carbonaceous mudstone slope,the peak shear stress of MAGM is,on average,55.3%greater than that of OPC. 展开更多
关键词 grouting material nanometer material water epoxy resin modification mechanism carbonaceous mudstone
在线阅读 下载PDF
A comprehensive comparison of hydro-elastoplastic-damage and capelastoplastic-damage material models for concrete subjected to impact and blast loadings
13
作者 Shufeng Shi Xiangzhen Kong +2 位作者 Junyu Fan Yong Peng Qin Fang 《Defence Technology(防务技术)》 2025年第5期83-104,共22页
Concrete material model plays an important role in numerical predictions of its dynamic responses subjected to projectile impact and charge explosion.Current concrete material models could be distinguished into two ki... Concrete material model plays an important role in numerical predictions of its dynamic responses subjected to projectile impact and charge explosion.Current concrete material models could be distinguished into two kinds,i.e.,the hydro-elastoplastic-damage model with independent equation of state and the cap-elastoplastic-damage model with continuous cap surface.The essential differences between the two kind models are vital for researchers to choose an appropriate kind of concrete material model for their concerned problems,while existing studies have contradictory conclusions.To resolve this issue,the constitutive theories of the two kinds of models are firstly overviewed.Then,the constitutive theories between the two kinds of models are comprehensively compared and the main similarities and differences are clarified,which are demonstrated by single element numerical examples.Finally,numerical predictions for projectile penetration and charge explosion experiments on concrete targets are compared to further demonstrate the conclusion made by constitutive comparison.It is found that both the two kind models could be used to simulate the dynamic responses of concrete under projectile impact and blast loadings,if the parameter needed in material models are well calibrated,although some discrepancies between them may exist. 展开更多
关键词 Concrete material model Hydro-elastoplastic-damage material model Cap-elastoplastic-damage model Projectile impact Charge explosion
在线阅读 下载PDF
Design,Synthesis and Optoelectronic Properties of Bipolar Host Materials Based on 9-penylcarbazole and Benzimidazole 被引量:1
14
作者 HUANG Hong XIONG Zhangqi +5 位作者 DENG Depeng XIA Weimin ZHANG Youming HUA Tao LI Nengquan XIE Guohua 《发光学报》 北大核心 2025年第12期2293-2301,共9页
Theoretically,blue phosphorescent materials are capable of achieving 100%internal quantum effi-ciency.Nevertheless,the mutual constraints among efficiency,color purity,and stability remain one of the key bottlenecks i... Theoretically,blue phosphorescent materials are capable of achieving 100%internal quantum effi-ciency.Nevertheless,the mutual constraints among efficiency,color purity,and stability remain one of the key bottlenecks in the industrialization of organic light-emitting diodes(OLEDs).In addition,the design and application of host materials also exert a significant impact on the overall performance of blue light-emitting de-vices.To address this issue,this study constructs a series of host materials with high triplet energy levels by designing different connection modes,based on 9-phenylcarbazole and benzimidazole units.Through a combi-nation of theoretical and experimental approaches,the correlation between the chemical structure and perfor-mance has been unraveled.It is found that the designed and synthesized blue phosphorescent bipolar host ma-terials based on different biphenyl linking sites,i.e.,9-(3'-(1-phenyl-1H-benzo[d]imidazol-2-yl)-[1,1'-bi-phenyl]-3-yl)-9H-carbazole(mCzmBI),9-(2'-(1-phenyl-1H-benzo[d]imidazol-2-yl)-[1,1'-biphenyl]-3-yl)-9H-carbazole(mCzoBI)and 9-(3'-(1-phenyl-1H-benzo[d]imidazol-2-yl)-[1,1'-biphenyl]-2-yl)-9H-carbazole(oCzmBI).The three compounds have a similar triplet energy level of 2.70 eV,accompanied with the glass transition temperatures of 92℃,103℃,and 93℃respectively.mCzmBI,mCzoBI and oCzmBI are regioiso-mers,but differ in the linking sites of carbazole and benzimidazole on the biphenyl linker.This difference in linking positions enables effective regulation of the host materials’properties.Constructed with the blue phos-phorescent material bis(4,6-difluorophenylpyridinato-N,C2)picolinatoiridium(Ⅲ)(FIrpic)as the guest,the influence of the three hosts on device performance is clarified.Overall,the device using mCzmBI,a host linked by biphenyl at double meta-positions,achieved a maximum current efficiency of 24.9 cd·A^(-1)and a max-imum external quantum efficiency exceeding 12.8%,it also demonstrates low efficiency roll-off under highbrightness conditions.This work offers an effective strategy to the development of high-efficiency blue phospho-rescent hosts. 展开更多
关键词 blue phosphorescent organic electroluminescence 9-phenylcarbazole BENZIMIDAZOLE host materials
在线阅读 下载PDF
Impact of pitch fraction oxidation on the structure and sodium storage properties of derived carbon materials 被引量:1
15
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
Investigation of mixing performance and safety characteristics of polymer-based energetic materials simulant via screw-pressing blending extrusion charges 被引量:2
16
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
Rapid removal of Cr(VI)from aqueous solution by novel sepiolite/Fe_(3)O_(4)/nZVI nanocomposite:Material characterizations,enhanced performance in Cr(VI)removal and mechanism 被引量:1
17
作者 HOU Kai HUANG Li +8 位作者 CHEN Wei LI Xue-lian HE Xi LIU Ai-fang DU Juan ZHAO Yue-jie YAO Shun WEI Yu-han FENG Guo-rui 《Journal of Central South University》 2025年第6期2071-2086,共16页
The novel magnetic sepiolite/Fe_(3)O_(4)/zero-valent iron(nZVI)nanocomposite(nZVI@SepH-Mag)was prepared and used to achieve the removal of Cr(VI)in this work.The nZVI@SepH-Mag composites were characterized by XRD,FTIR... The novel magnetic sepiolite/Fe_(3)O_(4)/zero-valent iron(nZVI)nanocomposite(nZVI@SepH-Mag)was prepared and used to achieve the removal of Cr(VI)in this work.The nZVI@SepH-Mag composites were characterized by XRD,FTIR,BET,SEM and TEM.The characterization results indicated that the structure of the composite consisted of small nanoscale nZVI and magnetite(Mag)particles uniformly anchoring on the surface of acid-activated sepiolite(SepH).Batch experiments were used to analyze the effects of main factors on Cr(VI)removal.A 100%removal efficiency in 60 min and enhanced reaction ratio were reached by the composite comparing other existing materials.The kinetic of the adsorption and possible Cr(VI)removal mechanism of the hybrids were also evaluated and proposed.Based on the removal products identified by Raman,XRD and XPS,a reduction mechanism was proposed.The results indicated that the SepH and Mag can inhibit the agglomeration and enhance the dispersibility of nZVI,and Mag and nZVI displayed good synergetic effects. 展开更多
关键词 magnetic adsorbent materials nanocomposites CR(VI) adsorption adsorption mechanism
在线阅读 下载PDF
Unprecedented energetic zwitterion integrating thermal stability,high energy density and low sensitivity:Overcoming performance trade-offs in conventional energetic materials 被引量:1
18
作者 Bojun Tan Xiong Yang +13 位作者 Jinkang Dou Jian Su Jing Zhang Siwei Song Changwei Tang Minghui Xu Shu Zeng Wenjie Li Jieyu Luan Gen Zhang Qinghua Zhang Xianming Lu Bozhou Wang Ning Liu 《Defence Technology(防务技术)》 2025年第10期220-229,共10页
The simultaneous integration of high energy density,low sensitivity,and thermal stability in energetic materials has constituted a century-long scientific challenge.Herein,we address this through a dualzwitterionic el... The simultaneous integration of high energy density,low sensitivity,and thermal stability in energetic materials has constituted a century-long scientific challenge.Herein,we address this through a dualzwitterionic electronic delocalization strategy,yielding TYX-3,the first bis-inner salt triazolo-tetrazine framework combining these mutually exclusive properties.Uniformπ-electron distribution and elevated bond dissociation energy confer exceptional thermal stability(T_(d)=365℃)with TATB-level insensitivity(impact sensitivity IS>40 J,friction sensitivity FS>360 N).Engineeredπ-stacked networks enable record density(1.99 g·cm^(-3))with detonation performance surpassing HMX benchmarks(detonation velocity 9315 m·s^(-1),detonation pressure 36.6 GPa).Practical implementation in Poly(3-nitratomethyl-3-methyloxetane)(PNMMFO)solid propellants demonstrates 5.4-fold safety enhancement over conventional HMX-based formulations while maintaining equivalent specific impulse.This work establishes a new design paradigm for energetic materials,overcoming the historical trade-offs between molecular stability and energy output through rational zwitterionic engineering. 展开更多
关键词 Energetic materials Triazolo-tetrazine framework High energy density Thermal stability Solid propellants
在线阅读 下载PDF
Analyzing fatigue behaviors and predicting fatigue life of cement-stabilized permeable recycled aggregate material 被引量:1
19
作者 YANG Tao XIAO Yuan-jie +6 位作者 LI Yun-bo WANG Xiao-ming HUA Wen-jun HE Qing-yu CHEN Yu-liang ZHOU Zhen MENG Fan-wei 《Journal of Central South University》 2025年第4期1481-1502,共22页
Permeable roads generally exhibit inferior mechanical properties and shorter service life than traditional dense-graded/impermeable roads.Furthermore,the incorporation of recycled aggregates in their construction may ... Permeable roads generally exhibit inferior mechanical properties and shorter service life than traditional dense-graded/impermeable roads.Furthermore,the incorporation of recycled aggregates in their construction may exacerbate these limitations.To address these issues,this study introduced a novel cement-stabilized permeable recycled aggregate material.A total of 162 beam specimens prepared with nine different levels of cement-aggregate ratio were tested to evaluate their permeability,bending load,and bending fatigue life.The experimental results indicate that increasing the content of recycled aggregates led to a reduction in both permeability and bending load.Additionally,the inclusion of recycled aggregates diminished the energy dissipation capacity of the specimens.These findings were used to establish a robust relationship between the initial damage in cement-stabilized permeable recycled aggregate material specimens and their fatigue life,and to propose a predictive model for their fatigue performance.Further,a method for assessing fatigue damage based on the evolution of fatigue-induced strain and energy dissipation was developed.The findings of this study provide valuable insights into the mechanical behavior and fatigue performance of cement-stabilized permeable recycled aggregate materials,offering guidance for the design of low-carbon-emission,permeable,and durable roadways incorporating recycled aggregates. 展开更多
关键词 cement-stabilized permeable recycle aggregate materials PERMEABILITY fatigue life prediction fatigue damage energy dissipation
在线阅读 下载PDF
Carbonated water erosion characteristics and mechanism of tunnel lining cement-based materials in karst environment 被引量:1
20
作者 ZOU Min LIU Juan-hong LI Kang 《Journal of Central South University》 2025年第8期3015-3034,共20页
The study aims to investigate the carbonated water erosion mechanism of lining concrete in tunnels traversing karst environment and enhance its resistance.In this study,dynamic carbonated water erosion was simulated t... The study aims to investigate the carbonated water erosion mechanism of lining concrete in tunnels traversing karst environment and enhance its resistance.In this study,dynamic carbonated water erosion was simulated to assess erosion depth,microstructure,phase migrations,and pore structure in various tunnel lining cement-based materials.Additionally,Ca^(2+)leaching was analyzed,and impact of Ca/Si molar ratio in hydration products on erosion resistance was discussed by thermodynamic calculations.The results indicate that carbonated water erosion caused rough and porous surface on specimens,with reduced portlandite and CaCO_(3) content,increased porosity,and an enlargement of pore size.The thermodynamic calculations indicate that the erosion is spontaneous,driven by physical dissolution and chemical reactions dominated by Gibbs free energy.And the erosion reactions proceed more spontaneously and extensively when Ca/Si molar ratio in hydration products was higher.Therefore,cement-based materials with higher portlandite content exhibit weaker erosion resistance.Model-building concrete,with C-S-H gel and portlandite as primary hydration products,has greater erosion susceptibility than shotcrete with ettringite as main hydration product.Moreover,adding silicon-rich mineral admixtures can enhance the erosion resistance.This research offers theory and tech insights to boost cement-based material resistance against carbonated water erosion in karst tunnel engineering. 展开更多
关键词 tunnel lining cement-based materials carbonated water erosion phase analysis pore structure Ca/Si molar ratio
在线阅读 下载PDF
上一页 1 2 28 下一页 到第
使用帮助 返回顶部