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Organic-inorganic composite coatings of PU-SMP@ZrO_(2)with enhancing corrosion/wear resistances
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作者 Zun-shuo Li Zhong-shan Wang +2 位作者 Ming-ming Liu Yong-ling Wu Hong-yu Zheng 《Journal of Iron and Steel Research International》 2025年第5期1212-1225,共14页
Metal wear and corrosion require a protective coating with good corrosion and wear resistance.The inorganic adhesive of methyltriethoxysilane modified silica sol(SMP)was first synthesized by the dehydration condensati... Metal wear and corrosion require a protective coating with good corrosion and wear resistance.The inorganic adhesive of methyltriethoxysilane modified silica sol(SMP)was first synthesized by the dehydration condensation of silica sol(S30)with methyltriethoxysilane in propyl alcohol.Then,SMP was used to modify the organic polyurethane(PU)by adjusting the volume ratio.The optimal ratio of the organic–inorganic hybrid adhesive PU-SMP was obtained by measuring its film-forming,mechanical,and corrosion-resistant properties.Then,PU-SMP and zirconia nanoparticles(ZrO_(2))were used as an adhesive and functional filler to prepare the organic–inorganic composite coating of PU-SMP@ZrO_(2)via spraying on various substrates.The fabricated PU-SMP@ZrO_(2)performed superior mechanical strength,good wear performance,and excellent anti-corrosion property.The pencil hardness of the coating PU-SMP@2.5ZrO_(2)is 7H,the wear mass is reduced from 0.7 to 0.2 mg,and the impedance modulus reached 10^(7)Ωcm^(2).The synthesized organic–inorganic hybrid adhesive and its composite coatings provide a promising approach for constructing functional protective coatings on mechanical engineering material. 展开更多
关键词 Metal protection composite resin coating ANTICORROSION Wear resistance Nano filler
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Nuclear magnetic resonance studies of organic-inorganic composite solid electrolytes 被引量:1
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作者 Xueyan Zhang Hua Huo 《Magnetic Resonance Letters》 2021年第2期142-152,共11页
Solid electrolytes have received widespread attention due to their higher safety than liquid electrolytes in the past decades.In particular,organic-inorganic composite solid electro-lytes(CSEs)in which inorganic fller... Solid electrolytes have received widespread attention due to their higher safety than liquid electrolytes in the past decades.In particular,organic-inorganic composite solid electro-lytes(CSEs)in which inorganic fllers dispersed in polymer solid electrolytes are consid-ered to be one of the most promising candidate electrolytes for high-performance solid-state lithium batteries.Understanding the local environments and the conduction pathway/dynamics of Lit is essential for the design of high-performance CSEs.Nuclear magnetic resonance(NMR)is a non-invasive quantitative technique that has unique ca-pabilities in providing molecular structure information,morphological evolution,and measuring the movement of ions at different time scales.Therefore,for battery re-searchers,an accurate and comprehensive under standing of the basic principles and experimental design of solid-state NMR(SSNMR)is of great significance for investigating the abundant molecular structure and dynamics information in CSEs.The specific appli-cations of the SSNMR technique in CSEs are briefly introduced in this present review. 展开更多
关键词 composite solid electrolytes(CSEs) Conduction pathway Solid-state NMR(SSNMR) Solid-state lithium batteries
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Development of an oral organic-inorganic hybrid nanocomposite for prolonged sustained release of nifedipine
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作者 Jia Yan Yanqin Liang +1 位作者 Cuishuan Wu Qiang Zhang 《Journal of Chinese Pharmaceutical Sciences》 2025年第7期605-621,共17页
Nifedipine(NF),a widely prescribed antihypertensive agent,necessitates long-term administration to maintain therapeutic efficacy.Although osmotic pump formulations,such as Bayer’s Adalat^(®),are well-established... Nifedipine(NF),a widely prescribed antihypertensive agent,necessitates long-term administration to maintain therapeutic efficacy.Although osmotic pump formulations,such as Bayer’s Adalat^(®),are well-established for achieving zero-order drug release,their complex manufacturing requirements significantly elevate production costs.In this study,we employed mesoporous silica as a drug carrier for nifedipine and incorporated it with an organic polymer matrix to construct an organic-inorganic hybrid nanocomposite(OIN).This nanostructured system demonstrated robust sustained-release properties in both in vitro and in vivo evaluations,with the in vitro release profile exhibiting classical first-order kinetics.To further optimize the release behavior,we combined OIN with conventional tablet-forming techniques to create an oral nanocomposite system(ONS)capable of achieving near-zero-order release.Remarkably,the cumulative release profiles of ONS closely mirrored those of the commercially available Adalat^(®)osmotic formulation across multiple time points.Moreover,we conducted a theoretical analysis of the release mechanisms underlying both OIN and ONS systems,offering novel mechanistic insights that could inform the future design of advanced sustained-release drug delivery platforms. 展开更多
关键词 NIFEDIPINE organic-inorganic hybrid nanocomposite Zero-order release SILICA Eudragit^(®)RSPO
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Advances in controlled-release fertilizer encapsulated by organic-inorganic composite membranes 被引量:3
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作者 Xueping Wang Yongyan Yang +5 位作者 Shuangling Zhong Qingye Meng Yiwei Li Jia Wang Yan Gao Xuejun Cui 《Particuology》 SCIE EI CAS CSCD 2024年第1期236-248,共13页
Heavy use of conventional fertilizers can lead to negative environmental concerns.Controlled-release fertilizers(CRFs)can effectively reduce the amounts of fertilizers used,improve the availability of fer-tilizers,and... Heavy use of conventional fertilizers can lead to negative environmental concerns.Controlled-release fertilizers(CRFs)can effectively reduce the amounts of fertilizers used,improve the availability of fer-tilizers,and which is conducive to the protection of the ecological environment and sustainable devel-opment of agriculture.Therefore,it is imperative to develop and use CRFs as an alternative to traditional fertilizers.This review aims to present the classification,raw material composition,benefits,release process,release mode,and manufacturing methods of fertilizers coated with organic-inorganic com-posite membranes(OICMs)in order to provide an overall update and summarize CRFs encapsulated by OICMs and provide an insight for future trends in the field of fertilizers.It is expected that utilizing CRFs encapsulated by OICMs and their characteristics for agricultural applications can provide innovative ideas and suggestions for developing novel CRFs suitable for modern and sustainable agriculture. 展开更多
关键词 Controlled-release fertilizers organic-inorganic composite membranes Surface treatments
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CdS-enzyme composite promotes photobiocatalytic conversion of plastic-derived lactate to chiral chemicals
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作者 Willy W.L.See Phuc T.T.Nguyen +4 位作者 Heng Yih Tan Jie Fu Jeff Zhou Sie Shing Wong Kang Zhou Ning Yan 《Green Energy & Environment》 2026年第2期523-530,共8页
The combination of photo-and bio-catalysis in one-pot enables sustainable,visible-light driven cascade reactions for the synthesis of valueadded chiral chemicals under mild conditions.Despite the attractiveness of mer... The combination of photo-and bio-catalysis in one-pot enables sustainable,visible-light driven cascade reactions for the synthesis of valueadded chiral chemicals under mild conditions.Despite the attractiveness of merging the redox capability of heterogeneous photocatalysts with the excellent enantioselectivity of enzymes,developing such a reaction under one-pot conditions poses a challenge due to catalyst incompatibility.In this study,a cadmium sulfide(CdS)-enzyme composite was engineered for one-pot conversion of plastic-derived lactate into chiral compounds.By coating CdS onto alginate beads,its redox capability for the oxidation of lactate in water under visible light was preserved.The generated pyruvate subsequently underwent enantioselective transformation catalyzed by encapsulated enzymes within the beads,producing(R)-acetoin,L-alanine,or(R)-phenylacetylcarbinol.The core-shell structure of the CdS-enzyme composite protects the enzymes against radical attacks and facilitates recycling,yielding 81% of(R)-acetoin achieved after four reaction cycles.Additionally,we demonstrated an upcycling process converting post-consumer polylactic acid cups into(R)-acetoin.This work introduces a novel approach for integrating photocatalysts and enzymes to synthesize chiral chemicals from end-of-life plastics. 展开更多
关键词 Asymmetric synthesis BIOCATALYSIS PHOTOCATALYSIS Plastic upcycling organic-inorganic hybrid composites
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Recent Progresses in Synthesis of Cyclic Polymers in Large-scale and Some Functionalized Composites
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作者 QU Kairu GUO Lyuzhou +3 位作者 WANG Wenbin YAN Xuzhou CAO Xuezheng YANG Zhenzhong 《高等学校化学学报》 北大核心 2026年第1期42-57,共16页
Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynam... Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering. 展开更多
关键词 Cyclic polymer Large-scale synthesis Single-chain nanoparticle Performance composite
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Material removal mechanism of SiC_(f)/SiC composites during ultrasonic-assisted scratching with vertical vibration 被引量:1
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作者 Zhigang DONG Guoqing YUAN +3 位作者 Yichuan RAN Haiqi SUN Jiansong SUN Yan BAO 《Chinese Journal of Aeronautics》 2026年第1期584-600,共17页
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
关键词 Ceramic-matrix composites Ultrasonic assisted scratching(UAS) Strain rate effect Dynamic mechanical property Material removal mechanism
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CoMoNiO-S/nickel foam heterostructure composite for efficient oxygen evolution catalysis performance
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作者 YANG Hong SHAO Shengjuan +2 位作者 LI Baoyi LU Yifan LI Na 《无机化学学报》 北大核心 2026年第1期203-215,共13页
A composite electrocatalyst,CoMoNiO-S/NF-110(NF is nickel foam),was synthesized through electrodeposition,followed by pyrolysis and then the vulcanization process.CoMoNiO-S/NF-110 exhibited a structure where Ni3S2 and... A composite electrocatalyst,CoMoNiO-S/NF-110(NF is nickel foam),was synthesized through electrodeposition,followed by pyrolysis and then the vulcanization process.CoMoNiO-S/NF-110 exhibited a structure where Ni3S2 and Mo2S3 nanoparticles were integrated at the edges of Co3O4 nanosheets,creating a rich,heterogeneous interface that enhances the synergistic effects of each component.In an alkaline electrolyte,the synthesized CoMoNiO-S/NF-110 exhibited superior electrocatalytic performance for oxygen evolution reaction(OER),achieving current densities of 100 and 200 mA·cm^(-2) with low overpotentials of 199.4 and 224.4 mV,respectively,outperforming RuO2 and several high-performance Mo and Ni-based catalysts.This excellent performance is attributed to the rich interface formed between the components and active sites exposed by the defect structure. 展开更多
关键词 oxygen evolution reaction VULCANIZATION composite electrocatalyst MoNi-based catalyst
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Effect of Gradient Layer Thickness on Anti-penetration Properties of 2024 Al/TC4 Laminated Composites
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作者 Wang Kangan Li Muxi +1 位作者 Hou Hua Zhao Yuhong 《稀有金属材料与工程》 北大核心 2026年第5期1170-1183,共14页
A gradient structure was introduced into a metal laminated target plate,and the anti-penetration simulation of the gradient structure was compared with that of a uniform-layer-thickness target plate by finite element ... A gradient structure was introduced into a metal laminated target plate,and the anti-penetration simulation of the gradient structure was compared with that of a uniform-layer-thickness target plate by finite element simulation.The analysis was verified by an impact experiment.Results show that the high-level thickness and appropriate percentage of Ti alloy at the upper side of the gradient structure provide greater impact resistance against the bullet,which increases the warhead breakage and enhances the anti-penetration performance.In addition,during the impact process,the stress is transmitted and reflected in the form of waves in each layer of the target plate,and the interaction between the compression and tension waves causes non-synergistic deformation of the target plate and leads to delamination.The gradient target plate takes penetration resistance a step further through the higher energy absorption rate and more consumption of the bullet kinetic energy.This research provides a theoretical basis for the application of gradient structures in metallic laminated armor. 展开更多
关键词 gradient structure laminated composites finite element analysis anti-penetration mechanism
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Design and synthesis of KIT-5/Beta composites under varied hydrothermal temperatures and evaluation of their hydrodenitrogenation performance
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作者 LIU Xing GUO Shaoqing +7 位作者 CUI Haitao LI Zhenrong LI Xin WANG Lei WU Xingjie WANG Xiaoxiao YUAN Lijing ZHAO Liangfu 《燃料化学学报(中英文)》 北大核心 2026年第1期46-57,共12页
KIT-5/Beta composite supports were synthesized using an in situ self-assembly hydrothermal method,and NiW/KIT-5/Beta catalysts were prepared by impregnation.A series of characterization techniques were utilized to eva... KIT-5/Beta composite supports were synthesized using an in situ self-assembly hydrothermal method,and NiW/KIT-5/Beta catalysts were prepared by impregnation.A series of characterization techniques were utilized to evaluate the influence of varying hydrothermal synthesis temperatures on the physicochemical properties of both the KIT-5/Beta supports and the resulting catalysts.The catalytic performances of catalysts were evaluated under reaction conditions of 320℃,4 MPa H_(2)pressure,and a weight hourly space velocity(WHSV)of 4.8 h^(-1)for hydrodenitrogenation(HDN)of quinoline.The results indicated that the specific surface area and pore structure of the materials could be effectively regulated by adjusting the hydrothermal synthesis temperature,which in turn influenced the number of active sites on the catalyst.The NiW/KB-125 catalyst,synthesized at 125℃,presented the highest quinoline HDN efficiency(96.8%),which can be attributed to its favorable pore channel structure,greater Brønsted acid number,higher degree of metal sulfidation(80.12%)and appropriate metal-support interaction(MSI). 展开更多
关键词 mesoporous-microporous material KIT-5/Beta composite NiWS QUINOLINE HYDRODENITROGENATION
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Facile Fabrication of Ceramic-resin Coatings on C/CA Composites for Oxidation Protection at Medium Temperatures
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作者 TIAN Hongwang LUO Longfei +4 位作者 HU Chenglong YAN Meng PANG Shengyang LI Jian TANG Sufang 《无机材料学报》 北大核心 2026年第3期401-408,I0008-I0011,共12页
Carbon fiber-reinforced carbon aerogel(C/CA)composites are one of the most promising candidates for applications requiring both thermal insulation and load bearing capabilities.The preparation of anti-oxidation coatin... Carbon fiber-reinforced carbon aerogel(C/CA)composites are one of the most promising candidates for applications requiring both thermal insulation and load bearing capabilities.The preparation of anti-oxidation coatings on C/CA to address its susceptibility to oxidation is a feasible approach to promote its application in oxidative environments.However,the currently reported coatings on C/CA mainly focus on improving the ablation performance and coating preparation process typically necessitating high-temperature heat treatment.This procedure can increase its thermal conductivity and reduce its thermal insulation ability.In this study,a series of ceramic-resin coatings were fabricated on C/CA through a simple slurry brushing-drying approach at room temperature.The effects of phenolic resin content on the coating structure,residual stress,thermal shock,and oxidation behaviors were investigated.Due to the adhesive properties and curing-induced shrinkage,the PR-7.5 coating(containing 7.5%(in mass)phenolic resin in the slurry)exhibits bonding strength close to fracture strength of the substrate and residual compressive stress of 0.853 GPa,which is beneficial for resisting thermal shock cracking.However,excessive resin content(PR-10.0 containing 10.0%(in mass)phenolic resin in the slurry)induces tensile stress due to uneven curing shrinkage,thereby leading to thermal shock cracking.Meanwhile,oxidation tests reveal significantly reduced weight losses for PR-7.5(17.46%at 800℃/100 min,8.15%at 1000℃/120 min,3.15%at 1200℃/120 min)versus uncoated C/CA’s 44.60%loss at 800℃/20 min.This work provides a brand-new and simple approach to improving the anti-oxidation performance of C/CA and expands its application in mild oxidative environments. 展开更多
关键词 C/CA composite coating OXIDATION residual stress interfacial bonding
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Post-synthetic modification strategy to construct Co-MOF composites for boosting oxygen evolution reaction activity
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作者 ZHENG Haifeng GUO Xingzhe +5 位作者 WEI Yunwei WANG Xinfang QI Huimin YAN Yuting ZHANG Jie LI Bingwen 《无机化学学报》 北大核心 2026年第1期193-202,共10页
The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecul... The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecules and{[Co2(BINDI)(DMA)_(2)]·DMA}_(n)(Co-MOF,H4BINDI=N,N'-bis(5-isophthalic acid)naphthalenediimide,DMA=N,N-dimethylacetamide)was synthesized via a one-pot method,leveragingπ-πinteractions between pyrene and Co-MOF to modulate electrical conductivity.Results demonstrate that the Py@Co-MOF catalyst exhibited significantly enhanced OER performance compared to pure Co-MOF or pyrene-based electrodes,achieving an overpotential of 246 mV at a current density of 10 mA·cm^(-2) along with excellent stability.Density functional theory(DFT)calculations reveal that the formation of O*in the second step is the rate-determining step(RDS)during the OER process on Co-MOF,with an energy barrier of 0.85 eV due to the weak adsorption affinity of the OH*intermediate for Co sites.CCDC:2419276. 展开更多
关键词 PYRENE metal-organic frameworks composite catalyst oxygen evolution reaction density functional theory
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Research Progress on High Thermal Conductivity Graphene/Copper-Based Composite Heat Sinks for Electronic Equipment
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作者 Li Hongzhao Jiang Haojie +3 位作者 Pan Jiabao Jia Hongsheng Chen Minghe Chen Yang 《稀有金属材料与工程》 北大核心 2026年第3期636-654,共19页
Graphene/copper-based composite heat sinks demonstrate extensive application potential in military equipment thermal management,high-power electronic packaging,new energy vehicles,and 5G communication systems,due to t... Graphene/copper-based composite heat sinks demonstrate extensive application potential in military equipment thermal management,high-power electronic packaging,new energy vehicles,and 5G communication systems,due to their outstanding properties,including high thermal conductivity,tunable thermal expansion coefficients,excellent mechanical strength,and low density.However,the industrial-scale application of these composites faces critical challenges during the fabrication of components with complex structures,such as inhomogeneous dispersion of graphene within the copper matrix and poor interfacial bonding between the two phases,which substantially undermine the overall performance of graphene/copper-based composites.To address these issues,the preparation methods for graphene/copper-based composite heat sinks were reviewed.For each method,a rigorous analysis was presented to clarify its inherent advantages and unavoidable restrictions.Furthermore,the latest research progress in addressing three core scientific challenges was synthesized,including uniform dispersion of graphene,interfacial optimization mechanisms,and molecular dynamics simulations for elucidating the structure-property relationships.Finally,the future development directions of graphene/copper-based composite heat sinks in engineering applications were prospected. 展开更多
关键词 graphene/copper-based composite heat sinks preparation methods interfacial bonding MECHANISM molecular dynamics
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Hybrid organic-inorganic modification on tunnel-structured α-MnO_(2) for high-performance aqueous zinc-ion battery
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作者 Mengdan Tian Chuanzheng Zhu Kun Luo 《Chinese Chemical Letters》 2026年第3期716-721,共6页
Rechargeable aqueous zinc-ion batteries(AZIBs)draw intensive attention due to their high security,low price and the abundant zinc source.However,the electrochemical behaviors of AZIBs are seriously affected by the cat... Rechargeable aqueous zinc-ion batteries(AZIBs)draw intensive attention due to their high security,low price and the abundant zinc source.However,the electrochemical behaviors of AZIBs are seriously affected by the cathode materials.Mn-based oxide cathodes have been extensively investigated owing to the superior electrochemical performances such as large theoretical capacity and high working voltage.In this work,we rationally design a high-performance cathode material using organic-inorganic comodification strategy.The inorganic Al^(3+)ions and organic poly-vinylpyrrolidone(PVP)are successfully incorporated into the tunnel α-MnO_(2)structure.Structural characterizations and DFT calculations indicates that the Zn^(2+)adsorption energy in the Al^(3+)/PVP co-intercalated tunnel α-MnO_(2)is effectively lowered when compared with the original material,facilitating fast ion diffusion and stable Zn^(2+)ion storage.Electrochemical tests indicate that the PVP-Al-MnO_(2)electrode exhibits excellent electrochemical performances,a capacity of 306.8 mAh/g at 0.3 A/g and 93.1%capacity retention over 2000 cycles at 1.0 A/g.In addition,the aqueous PVP-Al-MnO_(2)‖ZnClO_(4)‖Zn battery is able to operate properly at low temperature(-45℃).This work shows an encouraging strategy to the modification of materials for AZIBs and other multivalent ion systems. 展开更多
关键词 Aqueous zinc-ion batteries Hybrid organic-inorganic modification MnO_(2)electrode material Synergistic effect Stability
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Influence of Composite Microbial Self-healing Materials on the Repair of Mortar Cracks
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作者 WANG Hailiang ZHANG Yan +8 位作者 RONG Hui LIU Dee ZHANG Yiming DING Longhui GAI Qingshan QIU Peng HU Liping XU Feng AI Fengquan 《Journal of Wuhan University of Technology(Materials Science)》 2026年第2期427-434,共8页
We mixed Bacillus subtilis and brewing yeast to prepare composite microbial self-healing materials,and studied the self-healing effect of composite microorganisms in mortar cracks of different widths and cracking ages... We mixed Bacillus subtilis and brewing yeast to prepare composite microbial self-healing materials,and studied the self-healing effect of composite microorganisms in mortar cracks of different widths and cracking ages.The experimental results show that the performance and self-healing effect of composite micro-organisms are significantly better than those of single microorganisms.For cracks with widths of 0.2-0.4 mm,the repair effect of the composite microorganisms at 28 days is 42.7%and 71.2%higher than that of pure Bacillus and pure yeast,respectively.The repairing rate of the area with the widths of the cracks of 0.2-0.4,0.4-0.6,and 0.6-0.8 mm are 100%,77.3%,and 53.4%,respectively.The area repair rates corresponding to cracking ages of 56,90,and 180 days are 73.3%,55.4%,and 30.8%,respectively. 展开更多
关键词 MORTAR composite microorganisms cracks SELF-HEALING
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Dynamical analysis and nonlinear vibration control of integrated composite beam structure in thermal environment
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作者 Donghui LI Faming ZHANG +4 位作者 Qunfang LI Shang GAO Jian ZANG Yewei ZHANG Fengtian YANG 《Chinese Journal of Aeronautics》 2026年第1期278-300,共23页
Traditional dynamic analysis of mechanical structures,often limited to individual beams or plates,fails to fully capture their dynamic behaviors.In systems where space and mass are constrained,such as the battery supp... Traditional dynamic analysis of mechanical structures,often limited to individual beams or plates,fails to fully capture their dynamic behaviors.In systems where space and mass are constrained,such as the battery support structures in electric aircraft,conventional absorbers and isolators are insufficient for effective vibration control.This study simplifies the battery support structure of electric aircraft as an integrated composite beam consisting of three interconnected beams,and investigated its structural dynamics properties and nonlinear vibration control under thermal conditions caused by battery heat.The nonlinear vibration control is performed using the Nitinol steel wire ropes(Ni Ti-ST),with nonlinear damping properties.The natural frequencies of system are determined using the Rayleigh-Ritz technique.Theoretical results are validated through both Finite Element Method(FEM)and hammer tests.Moreover,the dynamic equations are derived using the Lagrange method and discretized via the Galerkin Truncation Method(GTM).The Harmonic Balance Method(HBM)is used to evaluate the vibration responses of the integrated model,with further verification through the Runge-Kutta Method(RKM).The experiments are conducted to corroborate the theoretical analysis.The results show that the system frequency changes in stages with the increase of the stiffness of the integrated composite beam connection.Especially in the case of varying environments,as the temperature increases,the frequency of system will first increase to a certain maximum value and then gradually decrease.Furthermore,the NiTi-ST effectively reduces vibration in the integrated composite beam,particularly under varying temperatures and external excitations. 展开更多
关键词 composite laminated beam Dynamics characteristic Integrated composite beam Modal experiment NiTiNOL steel wire rope Nonlinear vibration control
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Influence of Processing Route on the Mechanical Properties of Poly(Lactic Acid)-Poly(Caprolactone)-Basalt Fiber Composites Prepared via Planetary Extrusion
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作者 Declan Mary Colbert Eyman Manaf +9 位作者 Zeeshan Ali Steven Rowe Chris Doran Trevor Howard Vlasta Chyzna Evan Moore Alan J.Murphy Patrick Doran Golnoosh Abdeali Declan M.Devine 《Journal of Polymer Materials》 2026年第1期146-163,共18页
A comparative analysis was performed on poly(lactic acid)(PLA),poly(caprolactone)(PCL),basalt fiber(BF)composites produced using two distinct approaches:direct blending and masterbatching.The limitations of PLA-BF com... A comparative analysis was performed on poly(lactic acid)(PLA),poly(caprolactone)(PCL),basalt fiber(BF)composites produced using two distinct approaches:direct blending and masterbatching.The limitations of PLA-BF composites with regard to distribution and adhesion are well-documented,as are chemical treatment methods(addition of compatibilisers,surface treatments,silanization).This work aimed to study an industrially relevant potential solution of utilising a PCL-BF masterbatch,prepared as a 50/50 wt.%blend using planetary roller extrusion(PEX)to both improve the distribution and homogeneity of the fibers as well as provide a secondary adhesion site to facilitate improved mechanical properties of the final PLA-PCL-BF composite.The resultant materials were injection moulded to prepare ISO standard test specimens and tested on the basis of their physical properties via tensile testing,impact strength testing,flexural analysis,Fourier transforminfrared spectroscopy and water absorption capability.The results displayed that the incorporation of PCL and BF led to an increase in ductility of the composite materials,allowing for improvements in the inherent brittleness of virgin PLA.Major increases in the impact strength were achieved with the utilisation of a 25% PCL/BF masterbatch,allowing for a greater than 50%increase.As an overall observation,the use of a masterbatching process,opposed to direct blending of the constituent materials allows for a greater consistency of composite to be achieved at the expense of increased gains. 展开更多
关键词 PLA natural fibers composites planetary extrusion
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Optimal Structure Determination for Composite Laminates Using Particle Swarm Optimization and Machine Learning
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作者 Viorel Mînzu Iulian Arama 《Computers, Materials & Continua》 2026年第4期628-647,共20页
This work addresses optimality aspects related to composite laminates having layers with different orientations.RegressionNeuralNetworks can model the mechanical behavior of these laminates,specifically the stressstra... This work addresses optimality aspects related to composite laminates having layers with different orientations.RegressionNeuralNetworks can model the mechanical behavior of these laminates,specifically the stressstrain relationship.If this model has strong generalization ability,it can be coupled with a metaheuristic algorithm–the PSO algorithm used in this article–to address an optimization problem(OP)related to the orientations of composite laminates.To solve OPs,this paper proposes an optimization framework(OFW)that connects the two components,the optimal solution search mechanism and the RNN model.The OFW has two modules:the search mechanism(Adaptive Hybrid Topology PSO)and the Prediction and Computation Module(PCM).The PCM undertakes all the activities concerning the OP at hand:the stress-strain model,constraints checking,and computation of the objective function.Two case studies about the layers’orientations of laminated specimens are conducted to validate the proposed framework.The specimens belong to“Off-axis oriented specimens”and are subjects of two OPs.The algorithms for AHTPSO and for the two PCMs(one for each problem)are proposed and implemented by MATLAB scripts and functions.Simulations are carried out for different initial conditions.The solutions demonstrated that the OFW is effective and has a highly acceptable computational complexity.The limitation of using the OFWis the generalization ability of the RNN model or any other regression models.To harness the RNN model efficiently,it must have a very good generalization power.If this condition ismet,the OFWcan be integrated into any design process to make optimal choices of the layers’orientations. 展开更多
关键词 composite laminates metaheuristics PSO regression models
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Regulation of Microstructure,Mechanical Properties,and Corrosion Properties of Laser-Melting-Deposited B_(4)C/TC4 Composite by Heat Treatment
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作者 Zhao Cenya Zheng Yang +4 位作者 Xiong Ruize Ji Wenkang Zhang Daohong Liu Wei Tao Hailin 《稀有金属材料与工程》 北大核心 2026年第2期285-291,共7页
The TiB+TiC dual-reinforced B_(4)C/TC4 composite was in-situ fabricated via incorporating 0.5wt%B_(4)C reinforcement during the laser melting deposition process.Different heat treatments of annealing and solid solutio... The TiB+TiC dual-reinforced B_(4)C/TC4 composite was in-situ fabricated via incorporating 0.5wt%B_(4)C reinforcement during the laser melting deposition process.Different heat treatments of annealing and solid solution were used to regulate the microstructure,mechanical properties,and corrosion properties of B_(4)C/TC4 composite.Results show that with the increase in temperature from 500℃to 800°C,partial lamellarα-Ti in the as-deposited sample is gradually transformed into equiaxedα-Ti,accompanied by the disappearance of basketweave microstructure.At 1100°C,a small portion of TiC phase suffers fusion.This composite exhibits the optimal combination of strength and plasticity after annealing at 500℃for 4 h followed by furnace cooling,which is attributed to the stress release effect and the refined basketweave microstructure.However,this composite shows a decline in corrosion resistance after various heat treatments due to grain coarsening and micro-galvanic corrosion. 展开更多
关键词 B_(4)C/TC4 composite laser melting deposition heat treatment mechanical property corrosion property
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Flexible Gd‑MOF@PMMA/BMA composite film fluorescent sensor for highly sensitive detection of tyramine in bananas
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作者 ZHANG Xin JIAO Xinyi +4 位作者 BAI Wanqiao SUN Xuehua CUI Huali REN Yixia CHAI Hongmei 《无机化学学报》 北大核心 2026年第2期217-226,共10页
In this study,using 3,5‑di(3′,5′‑dicarboxylphenyl)‑1H‑1,2,4‑triazole(H4L)as ligands,a gadolinia‑based organic framework complex{[GdNa(L)(H_(2)O)3]·2H_(2)O}_(n)(Gd‑Na‑MOF)was successfully designed and synthesize... In this study,using 3,5‑di(3′,5′‑dicarboxylphenyl)‑1H‑1,2,4‑triazole(H4L)as ligands,a gadolinia‑based organic framework complex{[GdNa(L)(H_(2)O)3]·2H_(2)O}_(n)(Gd‑Na‑MOF)was successfully designed and synthesized by hydrothermal method.The structure and properties were systematically characterized and tested by techniques such as single‑crystal X‑ray diffraction,powder X‑ray diffraction,thermogravimetric analysis,infrared spectroscopy,and fluorescence spectroscopy.The results indicate that this complex has a unique 3D structure,excellent thermal stability,and outstanding luminescent performance.Based on its luminescent properties,a polymer‑embedding method was employed to fabricate the Gd‑Na‑MOF into a flexible,washable composite fluorescent film,Gd‑Na‑MOF@PMMA/BMA(PMMA=polymethyl methacrylate,BMA=butyl methacrylate).This fluorescent film exhibited highly sensitive recognition capability for tyramine,with a low detection limit of 1.66μmol·L^(-1).It was used for the detection of tyramine in bananas,with a recovery rate of 96.92%‑100.26%.CCDC:2466949. 展开更多
关键词 metal‑organic frameworks Gd‑Na‑MOF@PMMA/BMA composite fluorescent film fluorescent sensing TYRAMINE
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