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Syntheses,crystal structures,and catalytic properties of three zinc(Ⅱ),cobalt(Ⅱ)and nickel(Ⅱ)coordination polymers constructed from 5⁃(4⁃carboxyphenoxy)nicotinic acid 被引量:1
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作者 LING Weizhong CHEN Xiangyun +2 位作者 LIU Wenjing HUANG Yingkai LI Yu 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1803-1810,共8页
Three zinc(Ⅱ),cobalt(Ⅱ),and nickel(Ⅱ)coordination polymers,namely[Zn(μ^(3-)cpna)(μ-dpea)_(0.5)]_(n)(1),[Co(μ^(3-)cpna)(μ-dpey)_(0.5)]_(n)(2),and[Ni(μ^(3-)cpna)(μ-dpey)_(0.5)(H_(2)O)]_(n)(3),have been construc... Three zinc(Ⅱ),cobalt(Ⅱ),and nickel(Ⅱ)coordination polymers,namely[Zn(μ^(3-)cpna)(μ-dpea)_(0.5)]_(n)(1),[Co(μ^(3-)cpna)(μ-dpey)_(0.5)]_(n)(2),and[Ni(μ^(3-)cpna)(μ-dpey)_(0.5)(H_(2)O)]_(n)(3),have been constructed hydrothermally using H_(2)cpna(5-(4-carboxyphenoxy)nicotinic acid),dpea(1,2-di(4-pyridyl)ethane),dpey(1,2-di(4-pyridyl)ethylene),and zinc,cobalt,and nickel chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and single-crystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that three compounds crystallize in the triclinic system,space group P1.Compounds 1-3 show 2D layer structures.The catalytic activities in the Knoevenagel condensation reaction of these compounds were investigated.Compounds 1 and 2 exhibit effective catalytic activities in the Knoevenagel condensa-tion reaction at room temperature.For this reaction,various parameters were optimized,followed by the investiga-tion of the substrate scope.CCDC:2335676,1;2335677,2;2335678,3. 展开更多
关键词 coordination polymer dicarboxylic acid catalytic property Knoevenagel condensation reaction
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Achieving Synergistic Improvement in Dielectric and Energy Storage Properties of All-Organic Poly(Methyl Methacrylate)-Based Copolymers Via Establishing Charge Traps
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作者 Guanghu He Huang Luo +5 位作者 Chuanfang Yan Yuting Wan Dang Wu Hang Luo Yuan Liu Sheng Chen 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期308-319,共12页
How to achieve synergistic improvement of permittivity(ε_(r))and breakdown strength(E_(b))is a huge challenge for polymer dielectrics.Here,for the first time,theπ-conjugated comonomer(MHT)can simultaneously promote ... How to achieve synergistic improvement of permittivity(ε_(r))and breakdown strength(E_(b))is a huge challenge for polymer dielectrics.Here,for the first time,theπ-conjugated comonomer(MHT)can simultaneously promote theε_(r)and E_(b)of linear poly(methyl methacrylate)(PMMA)copolymers.The PMMA-based random copolymer films(P(MMA-co-MHT)),block copolymer films(PMMA-b-PMHT),and PMMA-based blend films were prepared to investigate the effects of sequential structure,phase separation structure,and modification method on dielectric and energy storage properties of PMMA-based dielectric films.As a result,the random copolymer P(MMA-coMHT)can achieve a maximumε_(r)of 5.8 at 1 kHz owing to the enhanced orientation polarization and electron polarization.Because electron injection and charge transfer are limited by the strong electrostatic attraction ofπ-conjugated benzophenanthrene group analyzed by the density functional theory(DFT),the discharge energy density value of P(MMA-co-PMHT)containing 1 mol%MHT units with the efficiency of 80%reaches15.00 J cm^(-3)at 872 MV m^(-1),which is 165%higher than that of pure PMMA.This study provides a simple and effective way to fabricate the high performance of polymer dielectrics via copolymerization with the monomer of P-type semi-conductive polymer. 展开更多
关键词 dielectric capacitor electrical properties energy density polymer dielectric semiconductor polymer
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Syntheses,structures,and properties of three coordination polymers based on 5⁃ethylpyridine⁃2,3⁃dicarboxylic acid and N⁃containing ligands
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作者 TANG Long BIAN Yaxin +3 位作者 CHEN Luyuan HOU Xiangyang WANG Xiao WANG Jijiang 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第10期1975-1985,共11页
Three coordination polymers[Mn(epda)(2,2'⁃bipy)(H_(2)O)](1),[Mn(epda)(phen)](2),and[Co_(2)(epda)2(bpe)2(H_(2)O)_(4)]·5H_(2)O(3)(H2epda=5⁃ethyl⁃pyridine⁃2,3⁃dicarboxylic acid,2,2'⁃bipy=2,2'⁃bipyridine,... Three coordination polymers[Mn(epda)(2,2'⁃bipy)(H_(2)O)](1),[Mn(epda)(phen)](2),and[Co_(2)(epda)2(bpe)2(H_(2)O)_(4)]·5H_(2)O(3)(H2epda=5⁃ethyl⁃pyridine⁃2,3⁃dicarboxylic acid,2,2'⁃bipy=2,2'⁃bipyridine,phen=phenanthroline,bpe=1,2⁃bis(4⁃pyridyl)ethylene)were synthesized by solvothermal reactions and characterized by single⁃crystal X⁃ray diffraction,thermogravimetric analyses,IR spectroscopy and elemental analysis.1 displays a 1D chain struc⁃ture,and these chains are joined by O-H…O hydrogen bonding andπ⁃πstacking interactions to generate a 2D layer structure.2 displays a 2D layer structure,and adjacent layers are generated 3D architecture throughπ⁃πstacking interactions.3 displays a 1D chain structure,and adjacent chains are generated double layer structure through O-H…O hydrogen bonding.The fluorescent properties of 1 and 3 indicate that they can potentially be used as a luminescent sensor.1 was highly selective and sensitive towards o⁃nitrophenol through different detection mechanisms,however,3 was highly selective and sensitive towards 2,4,6⁃trinitrophenol.In addition,the magnetic behavior of 2 has also been investigated.CCDC:2172533,1,2355773,2,2355774,3. 展开更多
关键词 coordination polymers 5⁃ethyl⁃pyridine⁃2 3⁃dicarboxylate ligand crystal structures fluorescent properties magnetic behavior
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Influence of Mass Ratio of Resin and Stabilizer on Mechanical Properties of Mo Fiber-reinforced Granite Polymer Composite
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作者 张超 任秀华 +6 位作者 BA Dongzhe ZHANG Jianhua LI Jianyong GUO Mengnan GAO Yinghao WANG Guixin LI Jiayang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期912-920,共9页
Because inferior mechanical strength of granite polymer composite(GPC)has become the main drawback limiting its application and popularization,Mo fibers were added into(GPC)to improve its mechanical strength.Mechanica... Because inferior mechanical strength of granite polymer composite(GPC)has become the main drawback limiting its application and popularization,Mo fibers were added into(GPC)to improve its mechanical strength.Mechanical properties of matrix materials with different mass ratio of resin and stabilizer(MRRS)were investigated systematically.The influences of MRRS on interface bonding strength of Mo fiber-matrix,wettability and mechanical strength of GPC were discussed,respectively,and the theoretical calculation result of MRRS k was obtained,with the optimal value of k=4.When k=4,tensile strength,tensile strain and fracture stress of the cured resin achieve the maximum values.But for k=7,the corresponding values reach the minimum.With the increase of MRRS k,surface free energy of the cured resin first increases and then decreases,while contact angles between Mo sample and matrix have displayed the opposite trend.Wettability of resin to Mo fiber is the best at k=4.Pulling load of Mo fiber and interface bonding strength appear the maximum at k=4,followed by k=5,k=3 the third,and k=7 the minimum.When k=4,mechanical properties of Mo fiber-reinforced GPC are optimal,which is consistent with the result of theoretical calculation.This study is of great significance to get better component formulas of Mo fiber reinforced GPC and to improve its application in machine tools. 展开更多
关键词 polymer composite FIBER mechanical strength interface bonding
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Physical-Rheological Properties and Performances of Rejuvenated(Styrene-Butadiene-Styrene)Asphalt with Polymerized-MDI and Aromatic Oil
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作者 Ao Lu Ming Xiong +3 位作者 Chen Chen Liangjiang Li Haibei Tan Xiong Xu 《Fluid Dynamics & Materials Processing》 EI 2024年第7期1633-1646,共14页
Traditional asphalt rejuvenators,like aromatic oil(AO),are known to be effective in improving the low-temperature properties and fatigue performances of aged SBS(styrene-butadiene-styrene)modified asphalt(SBSMA)binder... Traditional asphalt rejuvenators,like aromatic oil(AO),are known to be effective in improving the low-temperature properties and fatigue performances of aged SBS(styrene-butadiene-styrene)modified asphalt(SBSMA)binders and mixtures.However,these rejuvenators inevitably compromise their high-temperature properties and deformation resistances because they dilute asphalt binder but do not fix the damaged structures of aged SBS.In this study,a highly-active chemical called polymerized 4,4-diphenylmethane diisocyanate(PMDI)was used to assist the traditional AO asphalt rejuvenator.The physical and rheological characteristics of rejuvenated SBSMA binders and the moisture-induced damage and rut deformation performances of corresponding mixtures were comparatively evaluated.The results showed that the increasing proportion of AO compromises the hightemperature property and hardness of aged SBSMA binder,and an appropriate amount of PMDI works to compensate such losses;3%rejuvenator at mass ratio of AO:PMDI=70:30 can have a rejuvenated SBSMA binder with a high-temperature performance similar to that of fresh binder,approximately at 71.4°C;the use of AO can help reduce the viscosity of PMDI rejuvenated SBSMA binder for improving its workability;PMDI can help improve the resistance of AO rejuvenated SBSMA binder to deformation,especially at elevated temperatures,through its chemical reactions with aged SBS;moisture induction can enhance the resistance to damage of rejuvenated mixtures containing AO/PMDI or only PMDI;and the rejuvenator with a mass ratio of AO:PMDI=70:30 can lead the rejuvenated mixture to meet the application requirement,with a rut depth of only 2.973 mm,although more PMDI can result in a higher resistance of rejuvenated mixtures to high-temperature deformation. 展开更多
关键词 Aged SBS modified asphalt polymerized 4 4-diphenylmethane diisocyanate aromatic oil physical properties rheological properties mixture performance
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Synthesis of polyfarnesene based on aqueous free-radical polymerization and molecular dynamics simulation of its properties
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作者 WU Ming-li JIANG Jing +2 位作者 WANG Xiao-yu WANG Can-cai WANG Qing-fu 《合成橡胶工业》 CAS 2024年第6期507-507,共1页
Farnesene monomer,obtained through the bio-fermentation,offered a unique long side chain structure that served as an excellent platform for the synthesis of“bottlebrush-like”polymers with exceptional thermal propert... Farnesene monomer,obtained through the bio-fermentation,offered a unique long side chain structure that served as an excellent platform for the synthesis of“bottlebrush-like”polymers with exceptional thermal properties.Such polymers had immense potential in the production of polyurethane elastomers and adhesives.Hydroxyl-terminated polyfarnesene(PFD),which was safe,environmentally-friendly and pollution-free,was synthesized with farnesene as the monomer and industrial grade product hydrogen peroxide as the initiator by aqueous free-radical polymerization. 展开更多
关键词 properties. RADICAL MONOMER
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Compressive properties of glue-laminated timber circular post modified by basalt fiber reinforced polymer
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作者 WEI Peixing GUO Wenzhen +2 位作者 ZHAO Mingjing GUO Zhensheng WANG Jianhe 《林业工程学报》 CSCD 北大核心 2024年第5期67-74,共8页
Glued timber structure is one of the main forms of modern wood architecture,which has gradually developed towards mid-and high-rise buildings.Glue-laminated timber(GLT)is comprised of several laminates of parallel-to-... Glued timber structure is one of the main forms of modern wood architecture,which has gradually developed towards mid-and high-rise buildings.Glue-laminated timber(GLT)is comprised of several laminates of parallel-to-grain dimension lumber that are bonded together with durable,moisture resistant structural adhesives.GLT can be used in horizontal applications as a beam and in vertical applications as a post.So,its compressive performance has a significant impact on structural safety.Fiber reinforced polymers(FRPs)were commonly used to improve the bearing capacity of GLT components,and the structural and process parameters largely determined the reinforcement effect.This study was aimed at investigating the influence of structural and process parameters on the axial compression performance of GLT components.Three wrapping methods(middle-part,end-part and full wrapping)and three lengths(0.6,0.8,and 1.0 m)of wood post specimens were designed in this work and the axial compression performance and ductility of GLT post specimens modified by basalt fiber reinforced polymer(BFRP)were studied.The results showed that the effect of different BFRP wrapping methods on the compressive strength and elastic modulus of laminated wood was not statistically significant(P>0.05).The compressive bearing capacity of unreinforced GLT posts decreased with the increase of aspect ratio.The GLT posts with middle-part and end-part wrapping still followed this pattern,while the compressive bearing capacity of GLT posts with full wrapping showed a pattern of first decreasing and then increasing.For GLT with low aspect ratios(4.0 or 5.3),there was no correlation between the wrapping method and the compressive bearing capacity,while the compressive bearing capacity of GLT with a high aspect ratio(6.7)for middle-part,end-part and full wrapping increased by 3.5%,7.5%and 9.7%,respectively.Compared to the unreinforced group,the ultimate axial compressive strength and modulus of elasticity(MOE)of the 6-E series specimens reinforced at both ends decreased by 2.58%and 6.70%,respectively.The ultimate axial compressive strength of the 8-E specimens reinforced at both ends increased by 8.62%and the MOE decreased by 1.91%.The compressive strength of the 10-E specimens reinforced at both ends increased by 7.51%and the MOE increased by 8.14%.The failure modes of GLT with different aspects were consistent under the same BFRP wrapping,while the failure modes of GLT with the same aspect ratio were different for different BFRP wrapping methods.The ductility performance of GLT with different aspects ratio was improved by the BFRP wrapping. 展开更多
关键词 basalt fiber reinforced polymer(BFRP) GLT circular post bearing performance
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Recent research in mechanical properties of geopolymer-based ultrahigh-performance concrete:A review
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作者 G.Murali 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期67-88,共22页
Due to the growing need for sustainable and ultra-high-strength construction materials,scientists have created an innovative ultra-high-performance concrete called Geopolymer based ultra-highperformance concrete(GUHPC... Due to the growing need for sustainable and ultra-high-strength construction materials,scientists have created an innovative ultra-high-performance concrete called Geopolymer based ultra-highperformance concrete(GUHPC).Besides,in the last few decades,there have been a lot of explosions and ballistic attacks around the world,which have killed many civilians and fighters in border areas.In this context,this article reviews the fresh state and mechanical properties of GUHPC.Firstly,the ingredients of GUHPC and fresh properties such as setting time and flowability are briefly covered.Secondly,the review of compressive strength,flexure strength,tensile strength and modulus of elasticity of fibrous GUHPC.Thirdly,the blast and projectile impact resistance performance was reviewed.Finally,the microstructural characteristics were reviewed using the scanning electron microscope and X-ray Powder Diffraction.The review outcome reveals that the mechanical properties were increased when 30%silica fume was added to a higher dose of steel fibre to improve the microstructure of GUHPC.It is hypothesized that the brittleness of GUHPC was mitigated by adding 1.5%steel fibre reinforcement,which played a role in the decrease of contact explosion cratering and spalling.Removing the need for cement in GUHPC was a key factor in the review,indicating a promising potential for lowering carbon emissions.However,GUHPC research is still in its early stages,so more study is required before its full potential can be utilized. 展开更多
关键词 Mechanical properties BLAST Projectile impact FIBRE GEOpolymer Silica fume Alkaline activators
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Effect of neutral polymeric bonding agent on tensile mechanical properties and damage evolution of NEPE propellant
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作者 M.Wubuliaisan Yanqing Wu +3 位作者 Xiao Hou Kun Yang Hongzheng Duan Xinmei Yin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期357-367,共11页
Introducing Neutral Polymeric bonding agents(NPBA) into the Nitrate Ester Plasticized Polyether(NEPE)propellant could improve the adhesion between filler/matrix interface, thereby contributing to the development of ne... Introducing Neutral Polymeric bonding agents(NPBA) into the Nitrate Ester Plasticized Polyether(NEPE)propellant could improve the adhesion between filler/matrix interface, thereby contributing to the development of new generations of the NEPE propellant with better mechanical properties. Therefore,understanding the effects of NPBA on the deformation and damage evolution of the NEPE propellant is fundamental to material design and applications. This paper studies the uniaxial tensile and stress relaxation responses of the NEPE propellant with different amounts of NPBA. The damage evolution in terms of interface debonding is further investigated using a cohesive-zone model(CZM). Experimental results show that the initial modulus and strength of the NEPE propellant increase with the increasing amount of NPBA while the elongation decreases. Meanwhile, the relaxation rate slows down and a higher long-term equilibrium modulus is reached. Experimental and numerical analyses indicate that interface debonding and crack propagation along filler-matrix interface are the dominant damage mechanism for the samples with a low amount of NPBA, while damage localization and crack advancement through the matrix are predominant for the ones with a high amount of NPBA. Finally, crosslinking density tests and simulation results also show that the effect of the bonding agent is interfacial rather than due to the overall crosslinking density change of the binder. 展开更多
关键词 Solid propellant Bonding agent Mechanical properties Damage evolution Cohesive-zone model Interface debonding
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Effect of Ti Additions on Mechanical and Thermodynamic Properties of W-Ti Alloys: A First-principles Study
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作者 ZHANG Jian NIE Wei +5 位作者 HUANG Jin ZHU Ke LIU Ruxia ZHANG Ruizhi LUO Guoqiang SHEN Qiang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期246-257,共12页
The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional theory.... The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional theory.The results indicate that W-Ti alloys except W_(8)Ti_(8) are thermodynamically stable.The modulus and hardness of W-Ti alloys are smaller than those of pure tungsten and gradually decrease with increasing Ti concentration.However,their B/G ratios and Poisson's ratios exceed those of pure tungsten,suggesting that the introduction of Ti decreases the mechanical strength while enhancing the ductility of W-Ti alloys.The thermal expansion coefficients for W-Ti alloys all surpass those of pure tungsten,indicating that the introduction of titanium exacerbates the thermal expansion behavior of W-Ti alloys.Nevertheless,elevated pressure has the capacity to suppress the thermal expansion tendencies in titanium-doped tungsten alloys.This study offers theoretical insights for the design of nuclear materials by exploring the mechanical and thermodynamic properties of W-Ti alloys. 展开更多
关键词 FIRST-PRINCIPLES mechanical properties thermodynamic properties tungsten-titanium alloys
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Effect of a Carbon Fibre-steel Fibre-graphite Conductive Filler on the Electrothermal Properties of Cementitious Materials
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作者 FAN Yanan WEI Hong +1 位作者 ZHENG Hongyong DU Hongxiu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期141-151,共11页
Carbon fibre,steel fibre and graphite were used as conductive fillers to prepare cementitious materials with excellent electrothermal properties.The electrically conductive cementitious materials with different volume... Carbon fibre,steel fibre and graphite were used as conductive fillers to prepare cementitious materials with excellent electrothermal properties.The electrically conductive cementitious materials with different volume dosages were analysed through compressive and flexural strength,electrochemical impedance spectroscopy and temperature rise tests.An equivalent circuit model was established to study the electrically conductive heat generation mechanism in the electrically conductive cementitious composites.The results indicate that the mechanical properties of cementitious composite materials with a ternary conductive phase are better than those of pristine cementitious materials because the fibrous filler improves their mechanical properties.However,the incorporation of graphite in the material reduces its strength.Introducing fibrous and point-like conductive phase materials into the cementitious material enhances the overall conductive pathway and considerably reduces the electrical resistance of the cementitious material,enhancing its conductive properties.The volume ratios of carbon fibre,steel fibre and graphite that achieve an optimal complex doping in the cementitious material were 0.35%,0.6%and 6%,respectively.This was determined using the mutation point of each circuit element parameter as the percolation threshold.In addition,at a certain safety voltage,there is a uniform change between the internal and surface temperatures of the conductive cementitious material,and the heating effect in this materialis is considerably better than that in the pristine cementitious material. 展开更多
关键词 cementitious composites conductive fillers electrothermal properties electrochemical impedance spectroscopy
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Poly(lactic acid)/Poly(butylene adipate-co-terephthalate)films with simultaneous high oxygen barrier and fast degradation properties
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作者 Mengjing Yang Yuxi Mao +4 位作者 Penghui Zhang Jie Li Zeming Tong Zhenguo Liu Yanhui Chen 《Green Energy & Environment》 SCIE EI CAS 2025年第1期1-10,共10页
Although poly(lactic acid)(PLA)is a good environmentally-friendly bio-degradable polymer which is used to substitute traditional petrochemical-based polymer packaging films,the barrier properties of PLA films are stil... Although poly(lactic acid)(PLA)is a good environmentally-friendly bio-degradable polymer which is used to substitute traditional petrochemical-based polymer packaging films,the barrier properties of PLA films are still insufficient for high-barrier packaging applications.In this study,oxygen scavenger hydroxyl-terminated polybutadiene(HTPB)and cobalt salt catalyst were incorporated into the PLA/poly(butylene adipate-co-terephthalate)(PLA/PBAT),followed by melting extrusion and three-layer co-extrusion blown film process to prepare the composite films.The oxygen permeability coefficient of the composite film combined with 6 wt%oxygen scavenger and 0.4 wt%catalyst was decreased significantly from 377.00 cc·mil·m^(-2)·day^(-1)·0.1 MPa^(-1) to 0.98 cc·mil·m^(-2)·day^(-1)·0.1 MPa^(-1),showing a remarkable enhancement of 384.69 times compared with the PLA/PBAT composite film.Meanwhile,the degradation behavior of the composite film was also accelerated,exhibiting a mass loss of nearly 60%of the original mass after seven days of degradation in an alkaline environment,whereas PLA/PBAT composite film only showed a mass loss of 32%.This work has successfully prepared PLA/PBAT composite films with simultaneously improved oxygen barrier property and degradation behavior,which has great potential for high-demanding green chemistry packaging industries,including food,agricultural,and military packaging. 展开更多
关键词 Barrier property Oxygen scavenging Blow molding Eco-packaging Degradable composite film
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Mechanical Properties of Railway High-strength Manufactured Sand Concrete: Typical Lithology, Stone Powder Content and Strength Grade
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作者 WANG Zhen LI Huajian +3 位作者 HUANG Fali YANG Zhiqiang WEN Jiaxin SHI Henan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期194-203,共10页
In order to achieve the large-scale application of manufactured sand in railway high-strength concrete structure,a series of high-strength manufactured sand concrete(HMC)are prepared by taking the manufactured sand li... In order to achieve the large-scale application of manufactured sand in railway high-strength concrete structure,a series of high-strength manufactured sand concrete(HMC)are prepared by taking the manufactured sand lithology(tuff,limestone,basalt,granite),stone powder content(0,5%,10%,15%)and concrete strength grade(C60,C80,C100)as variables.The evolution of mechanical properties of HMC and the correlation between cubic compressive strength and other mechanical properties are studied.Compared to river sand,manufactured sand enhances the cubic compressive strength,axial compressive strength and elastic modulus of concrete,while its potential microcracks weaken the flexural strength and splitting tensile strength of concrete.Stone powder content displays both positive and negative effects on mechanical properties of HMC,and the stone powder content is suggested to be less than 10%.The empirical formulas between cubic compressive strength and other mechanical properties are proposed. 展开更多
关键词 manufactured sand concrete RAILWAY mechanical property LITHOLOGY stone powder content
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Bioinspired Passive Tactile Sensors Enabled by Reversible Polarization of Conjugated Polymers
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作者 Feng He Sitong Chen +3 位作者 Ruili Zhou Hanyu Diao Yangyang Han Xiaodong Wu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期361-377,共17页
Tactile perception plays a vital role for the human body and is also highly desired for smart prosthesis and advanced robots.Compared to active sensing devices,passive piezoelectric and triboelectric tactile sensors c... Tactile perception plays a vital role for the human body and is also highly desired for smart prosthesis and advanced robots.Compared to active sensing devices,passive piezoelectric and triboelectric tactile sensors consume less power,but lack the capability to resolve static stimuli.Here,we address this issue by utilizing the unique polarization chemistry of conjugated polymers for the first time and propose a new type of bioinspired,passive,and bio-friendly tactile sensors for resolving both static and dynamic stimuli.Specifically,to emulate the polarization process of natural sensory cells,conjugated polymers(including poly(3,4-ethylenedioxythiophen e):poly(styrenesulfonate),polyaniline,or polypyrrole)are controllably polarized into two opposite states to create artificial potential differences.The controllable and reversible polarization process of the conjugated polymers is fully in situ characterized.Then,a micro-structured ionic electrolyte is employed to imitate the natural ion channels and to encode external touch stimulations into the variation in potential difference outputs.Compared with the currently existing tactile sensing devices,the developed tactile sensors feature distinct characteristics including fully organic composition,high sensitivity(up to 773 mV N^(−1)),ultralow power consumption(nW),as well as superior bio-friendliness.As demonstrations,both single point tactile perception(surface texture perception and material property perception)and two-dimensional tactile recognitions(shape or profile perception)with high accuracy are successfully realized using self-defined machine learning algorithms.This tactile sensing concept innovation based on the polarization chemistry of conjugated polymers opens up a new path to create robotic tactile sensors and prosthetic electronic skins. 展开更多
关键词 Passive tactile sensors Reversible polarization of conjugated polymers Tactile perception Machine learning algorithm Object recognition
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Merging polymers of intrinsic microporosity and porous carbon-based zinc oxide composites in novel mixed matrix membranes for efficient gas separation
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作者 Muning Chen Jiemei Zhou +7 位作者 Jing Ma Weigang Zheng Guanying Dong Xin Li Zhihong Tian Yatao Zhang Jing Wang Yong Wang 《Green Energy & Environment》 SCIE EI CAS 2025年第1期203-213,共11页
Mixed matrix membranes(MMMs)have demonstrated significant promise in energy-intensive gas separations by amalgamating the unique properties of fillers with the facile processability of polymers.However,achieving a sim... Mixed matrix membranes(MMMs)have demonstrated significant promise in energy-intensive gas separations by amalgamating the unique properties of fillers with the facile processability of polymers.However,achieving a simultaneous enhancement of permeability and selectivity remains a formidable challenge,due to the difficulty of achieving an optimal match between polymers and fillers.In this study,we incorporate a porous carbon-based zinc oxide composite(C@ZnO)into high-permeability polymers of intrinsic microporosity(PIMs)to fabricate MMMs.The dipole–dipole interaction between C@ZnO and PIMs ensures their exceptional compatibility,mitigating the formation of non-selective voids in the resulting MMMs.Concurrently,C@ZnO with abundant interconnected pores can provide additional low-resistance pathways for gas transport in MMMs.As a result,the CO_(2) permeability of the optimized C@ZnO/PIM-1 MMMs is elevated to 13,215 barrer,while the CO_(2)/N_(2) and CO_(2)/CH_(4) selectivity reached 21.5 and 14.4,respectively,substantially surpassing the 2008 Robeson upper bound.Additionally,molecular simulation results further corroborate that the augmented membrane gas selectivity is attributed to the superior CO_(2) affinity of C@ZnO.In summary,we believe that this work not only expands the application of MMMs for gas separation but also heralds a paradigm shift in the application of porous carbon materials. 展开更多
关键词 Mixed matrix membranes polymers of intrinsic microporosity CO_(2)separation Porous carbon materials
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Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile
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作者 XU Jian-Qiang MA Zhao-Peng +2 位作者 CHENG Si LIU Zhi-Cong ZHU Guang-Lai 《原子与分子物理学报》 CAS 北大核心 2025年第4期27-32,共6页
The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this wo... The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this work.The following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution function.The results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient decreases.Additionally,the excess molar volume initially decreases,reaches a minimum,and then increases.The rules of radial distribution functions(RDFs)of characteristic atoms are different.With increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then decreases.This indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently. 展开更多
关键词 Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions
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Effects of aggregate size distribution and carbon nanotubes on the mechanical properties of cemented gangue backfill samples under true triaxial compression
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作者 Qian Yin Fan Wen +7 位作者 Zhigang Tao Hai Pu Tianci Deng Yaoyao Meng Qingbin Meng Hongwen Jing Bo Meng Jiangyu Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期311-324,共14页
The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compressio... The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of aggregates.The mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically analyzed.The results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,respectively.However,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the aggregates.Theσ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite trend.Theε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse aggregates.With increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure. 展开更多
关键词 cemented gangue backfill materials particle size distribution true triaxial compression test carbon nanotubes mechanical properties failure modes
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Processing,microstructure,and mechanical properties of wire arc additively-manufactured AZ91 magnesium alloy using cold arc process
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作者 Bai-hao CAI Ji-kang FAN +3 位作者 Jie LI Dong-qing YANG Yong PENG Ke-hong WANG 《中国有色金属学报》 北大核心 2025年第1期91-104,共14页
Thin walls of an AZ91 magnesium alloy with fine equiaxed grains were fabricated via cold arc-based wire arc additive manufacturing(CA-WAAM),and the droplet transfer behaviours,microstructures,and mechanical properties... Thin walls of an AZ91 magnesium alloy with fine equiaxed grains were fabricated via cold arc-based wire arc additive manufacturing(CA-WAAM),and the droplet transfer behaviours,microstructures,and mechanical properties were investigated.The results showed that the cold arc process reduced splashing at the moment of liquid bridge breakage and effectively shortened the droplet transfer period.The microstructures of the deposited samples exhibited layered characteristics with alternating distributions of coarse and fine grains.During layer-by-layer deposition,the β-phase precipitated and grew preferentially along grain boundaries,while the fineη-Al_(8)Mn_(5)phase was dispersed in the α-Mg matrix.The mechanical properties of the CA-WAAM deposited sample showed isotropic characteristics.The ultimate tensile strength and elongation in the building direction(BD)were 282.7 MPa and 14.2%,respectively.The microhardness values of the deposited parts were relatively uniform,with an average value of HV 69.6. 展开更多
关键词 AZ91 magnesium alloy droplet transfer MICROSTRUCTURE mechanical properties cold arc process
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Characterization and correlation of engineering properties with microstructure in peanuts:A microscopic to macroscopic analysis
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作者 Fei Xiang Zhenyuan Li +9 位作者 Yichen Zheng Caixia Ding Benu Adhikari Xiaojie Ma Xuebing Xu Jinjin Zhu Bello Zaki Abubakar Aimin Shi Hui Hu Qiang Wang 《Journal of Integrative Agriculture》 2025年第1期339-352,共14页
Peanut varieties are diverse globally,with their characters and nutrition determining the product quality.However,the comparative analysis and statistical analysis of key quality indicators for peanut kernels across t... Peanut varieties are diverse globally,with their characters and nutrition determining the product quality.However,the comparative analysis and statistical analysis of key quality indicators for peanut kernels across the world remains relatively limited,impeding the comprehensive evaluation of peanut quality and hindering the industry development on a global scale.This study aimed to compare and analyze the apparent morphology,microstructure,single-cell structure,engineering and mechanical properties,as well as major nutrient contents of peanut kernels from 10 different cultivars representing major peanut-producing countries.The surface and cross-section microstructure of the peanut kernels exhibited a dense“blocky”appearance with a distinct cellular structure.The lipid droplets were predominantly spherical with a regular distribution within the cells.The single-cell structure of the kernels from these 10 peanut cultivars demonstrated varying morphologies and dimensions,which exhibited correlations with their mechanical and engineering properties.Furthermore,the mass loss versus temperature profiles of the peanut kernels revealed five distinct stages,corresponding to moisture loss,volatile loss,protein denaturation,and the degradation of various biomacromolecules.Variations were also observed in the lipid,protein,and sucrose contents,texture,bulk density,true density,porosity,geometric mean diameter,and sphericity among the diferent peanut varieties.This study establishes relationships and correlations among microstructure,engineering properties,and nutritional composition of commonly grown peanut varieties in major peanut-processing countries.The findings provide valuable insights into peanut quality evaluation,empowering the peanut industry to enhance their processing and product development efforts. 展开更多
关键词 peanut kernels apparent morphology MICROSTRUCTURE engineering properties mechanical properties
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Corrosion resistance and antibacterial properties of Ti−3Cu alloy prepared by selective laser melting
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作者 Meng-zhen ZHU Jing-lei MIAO +3 位作者 Xiong-wen ZHOU Er-lin ZHANG Zhi-lin LIU Hai-lin YANG 《中国有色金属学报》 北大核心 2025年第1期143-156,共14页
The corrosion resistance and antibacterial properties of Ti−3Cu alloy prepared by selective laser melting were evaluated using electrochemical experiments and a variety of antibacterial characterization.It is found th... The corrosion resistance and antibacterial properties of Ti−3Cu alloy prepared by selective laser melting were evaluated using electrochemical experiments and a variety of antibacterial characterization.It is found that the charge transfer resistance of Ti−3Cu alloy was 4.89×10^(5)Ω∙cm^(2),which was doubled the data obtained by CP-Ti alloy.The antibacterial rates of Ti−3Cu alloy against S.mutans and P.gingivalis were 45.0%and 54.5%.And the antibacterial rates increased with the prolongation of cultivation time,reaching up to 62.8%and 68.6%,respectively.The in-situ nano Ti_(2)Cu precipitates were homogeneously distributed in the matrix of the Ti−3Cu alloy,which was the key reason of increasing the corrosion resistance.Additionally,the microscale electric fields between theα-Ti matrix and the Ti_(2)Cu was responsible for the enhancement of the antibacterial properties. 展开更多
关键词 selective laser melting Ti−3Cu alloy MICROSTRUCTURE corrosion resistance antibacterial properties
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