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【新文速递】2024年9月20日复合材料SCI期刊最新文章

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今日更新:Composite Structures 2 篇,Composites Part A: Applied Science and Manufacturing 1 篇,Composites Part B: Engineering 1 篇,Composites Science and Technology 3 篇

Composite Structures

Vibration characteristics and response behaviors of three-dimensional-four-directional knitted composite sandwich cylindrical shells with pyramidal latticed cellular cores

Bocheng Dong, Kaiping Yu, Rui Zhao

doi:10.1016/j.compstruct.2024.118582

具有锥体网格芯的三维四向编织复合材料夹层圆柱壳的振动特性及响应行为

Responding to the stringent lightweight and mechanical performance requirements of aerospace vehicle devices, a novel sandwich cylindrical shell structure with three-dimensional-four-directional knitted composite skins and pyramidal latticed cellular cores is tailored as a well-optioned scheme for the critical components. A desired dynamic model of the goal structure under free and forced vibration occasions is proposed first as a prediction tool for coping with the existing lack, and the virtual spring technique is filled in the developed model to extend arbitrary boundary conditions. In the framework of the theoretical formulations constructed, explicit expressions for the effective mechanical properties of spatially knitted composite skins and cellular cores are derived. Afterwards, the first-order shear deformation shell theory and Jacobi-Ritz approach are utilized to deduce energy expressions, and the mode shapes, inherent frequencies, response amplitude, and decay signature are solved by adopting the eigenvalue and Newmark-Beta techniques. Compliant model parameters with low running costs and guaranteed calculation precision are given in convergence analyses, which pave the path for efficient data output and numerical calibration. After undertaking the model validation work, the impact laws of key variables on the dynamic indicators are released, with some contributions being made conducive to upgrading the vibration resistance capabilities.

针对航空航天飞行器对轻量化和力学性能的严格要求,设计了一种新型的夹层圆柱壳结构,该结构具有三维四向针织复合材料蒙皮和锥体网格蜂窝芯,是关键部件的优选方案。首先提出了目标结构在自由振动和强迫振动情况下的理想动力学模型,作为一种预测工具,弥补了现有的不足,并在所建立的模型中填充了虚拟弹簧技术,扩展了任意边界条件。在构建的理论公式框架内,导出了空间编织复合材料表皮和蜂窝芯的有效力学性能的显式表达式。然后,利用一阶剪切变形壳理论和Jacobi-Ritz方法推导能量表达式,采用特征值和Newmark-Beta技术求解模态振型、固有频率、响应幅值和衰减特征。在收敛分析中给出了运行成本低、计算精度有保证的模型参数,为有效的数据输出和数值标定铺平了道路。在承担了模型验证工作后,发布了关键变量对动力指标的影响规律,为提升抗振能力做出了一定贡献。


Study on stable configurations and snap through of the rectangular VS bi-stable laminates with curvilinear fiber alignment

C.C. Wu, Y.X. Hao, W. Zhang

doi:10.1016/j.compstruct.2024.118588

曲线纤维对中矩形VS双稳态层合板的稳定构型及通断研究

With advances in fiber placement technology, variable stiffness bistable laminates (VSBL) composited by curvilinear fiber format become a subject of intense interest for morphing structures due to their lower weight, adjustable stiffness and a richer range of stable configurations compared to straight fiber bistable laminate. Merely conducting research on square laminates is not enough allowing for practical application scenarios. This article investigates the influence of geometrical parameters of VSBL on the stable state configuration and static snap through actuated by MFC systematically. A quadratic variable curvature polynomial is used to fit the transverse displacement according to classical laminate theory. By means of von-Karman geometrical relationship and the Rayleigh-Ritz method, stable configurations of the VS bistable laminate are solved. By comparing with finite element results, the reliability and precision of the current results are verified. It shows that changing fiber orientation leads to significant effects on the steady state configuration and critical bifurcation points. Theoretical analysis of VS bistable laminates containing the smart piezoelectric material MFC is followed by analytical modeling. The voltage threshold required for actuating snap through of two stable states is acquired by smart material layer MFC. The specific reasons for the differences in the configurations of VS bistable laminates are illustrated by analyzing distribution of the stiffness of VSBL in the plane.

随着纤维铺层技术的进步,曲线纤维复合的变刚度双稳态层压板(VSBL)由于其较直纤维双稳态层压板具有更轻的重量、可调的刚度和更丰富的稳定结构范围而成为变形结构研究的热点。仅仅对方形层压板进行研究是不够的,考虑到实际应用场景。本文系统地研究了由MFC驱动的VSBL的几何参数对其稳态结构和静态断裂的影响。根据经典层叠理论,采用二次变曲率多项式拟合横向位移。利用von-Karman几何关系和Rayleigh-Ritz方法,求解了VS双稳态层压板的稳定构型。通过与有限元计算结果的比较,验证了现有计算结果的可靠性和精度。结果表明,改变光纤取向对光纤的稳态结构和临界分岔点有显著影响。对含有智能压电材料MFC的VS双稳态层合板进行了理论分析,并进行了解析建模。通过智能材料层MFC获取两种稳定状态触发断通所需的电压阈值。通过分析VSBL在平面内的刚度分布,阐述了VS双稳层板构型差异的具体原因。


Composites Part A: Applied Science and Manufacturing

Modeling of multi-scale 3-D conductive network and electrical conductivity of carbon fiber braided composites

Yousong Xue, Zhiyong Li, Gen Li, Xin Xu, Jun Ding, Bohong Gu, Baozhong Sun

doi:10.1016/j.compositesa.2024.108479

碳纤维编织复合材料多尺度三维导电网络及导电性建模

The prediction of electrical conductivity and current conduction path of carbon fiber 3-D braided composites is challenging due to its complex microstructure. This paper presents a modeling approach for establishing the multi-scale 3-D conductive network to study the current conduction behavior of the braided composites. The real microstructures, including the random distribution and random contact of carbon fibers at the micro-scale, the spatial path of carbon fiber yarn, and the yarn contact at the meso-scale, have been considered in the model. The conductive network models are valid for the conductivity prediction of the yarn and the composites. The electric potential distribution and current conduction path inside the yarn and the composites have been obtained with the multi-scale 3-D conductive network. This work provides a modeling method with high computational efficiency and simple implementation to quickly predict and design the conductivity of 3-D braided composites.

碳纤维三维编织复合材料由于其复杂的微观结构,其电导率和电流传导路径的预测具有一定的挑战性。本文提出了一种建立多尺度三维导电网络的建模方法,用于研究编织复合材料的电流传导行为。模型考虑了碳纤维在微观尺度上的随机分布和随机接触、碳纤维纱线的空间路径以及纤维在中观尺度上的接触等真实微观结构。所建立的导电网络模型对纱线和复合材料的电导率预测是有效的。利用多尺度三维导电网络得到了纱线和复合材料内部的电势分布和电流传导路径。为三维编织复合材料电导率的快速预测和设计提供了一种计算效率高、实现简单的建模方法。


Composites Part B: Engineering

Performance-Tunable Thermal Barrier Coating for Carbon Fiber-Reinforced Plastic Composite Materials via Flame Spraying

Heejin Kim, Kandasamy Praveen, Min Wook Lee, Juhyeong Lee

doi:10.1016/j.compositesb.2024.111842

碳纤维增强塑料复合材料火焰喷涂性能可调热障涂层研究

Thermal barrier coatings (TBCs) are essential for improving the heat resistance of materials operating in high-temperature environments. This paper proposes a new method for manufacturing double-layered TBC with graded porosity for carbon fiber-reinforced plastic (CFRP) composites. The TBC was created by a flame spraying process, consisting of relatively dense and porous layers: (1) a dense layer was produced by spraying yttria-stabilized zirconia (YSZ) particles directly onto neat carbon fabric substrate and (2) a porous layer was prepared by co-spraying YSZ particles with sacrificial polyetheretherketone (PEEK) particles. The porosity of the porous layer was controlled by varying a PEEK injection distance (D) and a PEEK feed rate (R). The correlation between porosity and thermal conductivity of the TBC layer was investigated to assess its thermal barrier performance. The TBC was fabricated with the D of 5 cm and the R of 1.0 g/min, and double-layered/CFRP composites were manufactured using partially cured CFRP and vacuum forming. The 660-μm-thick TBC with 34% porosity and 0.27 W/m∙K thermal conductivity protected the CFRP substrate remarkably under the subjected torch at 500°C, as the TBC layer reduced the surface temperature of CFRP beyond (TCFRP) 230°C. Thermomechanical analysis, following thermal shock tests, revealed that the double-layered TBC/CFRP composite retained 87% and 75% of its pristine flexural strength and modulus, respectively, while the neat CFRP composite was completely burnt out. This study explored the application of flame spray technology to develop highly effective double-layered TBCs with tunable porosity to maximize their thermal barrier performances. All results from the current study provide new insights into the design and development of CFRP composites and, by extension, TBCs for fiber composites, which will benefit a wide range of lightweight high-temperature applications.

热障涂层对于提高材料在高温环境下的耐热性至关重要。提出了一种制备碳纤维增强塑料(CFRP)复合材料双层渐变孔隙度TBC的新方法。TBC采用火焰喷涂工艺制备,由致密层和多孔层组成:(1)将氧化钇稳定的氧化锆(YSZ)颗粒直接喷涂到整齐的碳织物基底上,形成致密层;(2)将YSZ颗粒与牺牲聚醚醚酮(PEEK)颗粒共喷涂,形成多孔层。通过改变PEEK注入距离(D)和PEEK进料速率(R)来控制多孔层的孔隙度。研究了TBC层孔隙度与导热系数之间的相关性,以评估其热障性能。采用D = 5 cm, R = 1.0 g/min制备TBC,采用CFRP部分固化和真空成型制备双层/CFRP复合材料。厚度为660 μm,孔隙率为34%,导热系数为0.27 W/m∙K的TBC层在500℃时对CFRP基板的保护作用显著,使CFRP在230℃以上的表面温度降低。热冲击试验后的热力学分析表明,双层TBC/CFRP复合材料分别保留了其原始抗弯强度和模量的87%和75%,而纯CFRP复合材料完全烧毁。本研究探索了应用火焰喷射技术开发具有可调孔隙度的高效双层tbc,以最大限度地提高其热障性能。目前研究的所有结果都为CFRP复合材料的设计和开发提供了新的见解,进而为纤维复合材料的tbc提供了新的见解,这将有利于广泛的轻质高温应用。


Composites Science and Technology

Hybrid-structured carbon fiber fabric/silk fiber non-woven fabric/carbonyl iron powder/epoxy composites with highly efficient electromagnetic interference shielding and mechanical properties

Lieran Huang, Yuxin He, Ziang Gao, Houyi Du, Ruilin Zhang, Li Zhang, Hu Liu, Chuntai Liu, Changyu Shen

doi:10.1016/j.compscitech.2024.110868

 

具有高效电磁干扰屏蔽和机械性能的混合结构碳纤维织物/丝纤维无纺布/羰基铁粉/环氧复合材料

In this study, carbonyl iron powder (CIP) was loaded onto the surfaces of carbon fiber fabric (CF) and silk non-woven fabric (SF) through a spraying process and surface micro-dissolve & adhesion (SMDA) process, respectively. Subsequently, CF/SF/CIP reinforced epoxy (CF/SF/CIP/EP) composites with different hybrid structures were fabricated using vacuum-assisted resin transfer molding (VARTM) technique. The effects of these hybrid structures on both the electromagnetic interference (EMI) shielding performance and mechanical properties of the composites were systematically assessed. The results reveal that with an increase in the layer fraction of CF, the mechanical properties of the modified hybrid fibers (HFs) composites demonstrate a positive hybrid effect. Particularly noteworthy is the observation that when the layer ratio of CF to SF is maintained at 1:1, the M-CSCS/EP composites featuring an interlayer hybrid structure exhibit the highest EMI shielding effectiveness of 34.9 dB within the X-band of 8.2-12.4 GHz. This enhancement is attributed to the improved interfacial polarization loss capability of incident electromagnetic waves, facilitated by the increased two-phase interface formed between CF and SF. Moreover, the composite exhibits excellent mechanical properties, including a tensile strength of 339.9 MPa, interlaminar shear strength of 32.1 MPa, and impact strength of 98.2 kJ/m2. Consequently, the HFs composites developed in this study offer a commendable balance between EMI shielding performance and mechanical properties, rendering them highly suitable for a wide array of applications in aerospace, rail transportation, and communication equipment.

本研究将羰基铁粉(CIP)分别通过喷涂工艺和表面微溶解与粘附(SMDA)工艺加载到碳纤维织物(CF)和真丝无纺布(SF)表面。随后,采用真空辅助树脂传递模塑(VARTM)技术制备了不同混杂结构的CF/SF/CIP增强环氧树脂(CF/SF/CIP/EP)复合材料。系统评价了这些杂化结构对复合材料电磁干扰屏蔽性能和力学性能的影响。结果表明,随着CF层数的增加,改性混杂纤维(HFs)复合材料的力学性能表现出积极的混杂效应。特别值得注意的是,当CF与SF的层比保持在1:1时,具有层间杂化结构的M-CSCS/EP复合材料在8.2-12.4 GHz的x波段内具有最高的34.9 dB的EMI屏蔽效能。这种增强是由于CF和SF之间形成的两相界面增加,提高了入射电磁波的界面极化损耗能力。复合材料具有优异的力学性能,抗拉强度为339.9 MPa,层间剪切强度为32.1 MPa,冲击强度为98.2 kJ/m2。因此,本研究中开发的高频复合材料在EMI屏蔽性能和机械性能之间提供了值得称赞的平衡,使其非常适合在航空航天,铁路运输和通信设备中的广泛应用。


Cold Crystallization Behavior of Poly(Lactic Acid) Induced by Poly(Ethylene Glycol)-Grafted Graphene Oxide: Crystallization Kinetics and Polymorphism

Yang Su, Si-Ru Li, Si-Yuan Zhou, Hao-Ran Yang, Ling Xu, Gan-Ji Zhong, Jia-Zhuang Xu, Zhong-Ming Li, Xiao-Ming Tao, Yiu-Wing Mai

doi:10.1016/j.compscitech.2024.110871

 

聚乙二醇接枝氧化石墨烯诱导聚乳酸冷结晶行为:结晶动力学和多态性

Cold crystallization between the glass transition and melt temperature is of particular significance for crystalline regulation due to the slow crystallization rate of poly(lactic acid) (PLA). Incorporation of nucleation agents can promote PLA crystallization by reducing the nucleation activation energy and offering nucleation sites. Herein, we investigated the cold crystallization behavior of PLA induced by poly(ethylene glycol)-grafted graphene oxide (PEGgGO) which was synthesized and identified as a powerful nucleation agent for melt crystallization. The obtained results showed that PEGgGO not only accelerated the cold crystallization kinetics of PLA, but also promoted the polymorphic transition kinetics during the heating process. The half crystallization time of PLA induced by PEGgGO was shortened by 51% and the final crystallinity increased by 57% compared to that induced by GO alone at the same loading of 0.5 wt.%. In addition, relative to GO, PEGgGO enabled the α′-to-α phase transition kinetics of PLA by a reduced transition temperature range of 26% due to its excellent nucleation ability even at cold crystallization. The flexible PEG chains on GO facilitated crystalline regulation of PLA owing to the improved chain mobility. This work provides a broader framework for fashioning semicrystalline PLA products with enhanced crystallinity and refined crystal structure towards prospective applications.

由于聚乳酸(PLA)的结晶速度慢,玻璃化转变和熔体温度之间的冷结晶对结晶调节具有特殊的意义。成核剂的加入通过降低成核活化能和提供成核位点来促进聚乳酸的结晶。本文研究了聚乙二醇接枝氧化石墨烯(PEGgGO)诱导聚乳酸的冷结晶行为。聚乙二醇接枝氧化石墨烯(PEGgGO)是一种强大的熔融结晶成核剂。结果表明,PEGgGO不仅加速了聚乳酸的冷结晶动力学,而且在加热过程中促进了聚乳酸的多晶转变动力学。在相同负载0.5% wt.%的情况下,PEGgGO诱导聚乳酸的半结晶时间比单独使用GO诱导聚乳酸的半结晶时间缩短51%,最终结晶度提高57%。此外,由于PEGgGO具有优异的成核能力,即使在冷结晶时,PEGgGO也能使PLA的α′-α相变动力学降低26%。氧化石墨烯上的柔性聚乙二醇链由于提高了链的迁移率而促进了聚乳酸的结晶调节。这项工作为塑造具有增强结晶度和精细晶体结构的半结晶PLA产品提供了更广泛的框架,以实现潜在的应用。


Interface reinforced by polymer binder for expandable carbon fiber structural lithium-ion battery composites

Jianxun Li, Xu Liu, Zihan Hu, Yuehua Liu, Hongfei Li, Limin Zhou

doi:10.1016/j.compscitech.2024.110873

 

聚合物粘结剂增强可膨胀碳纤维结构锂离子电池复合材料界面

Carbon fiber (CF) composite structural battery (SB) is a novel energy storage device that integrates electrochemical energy storage with mechanical load-bearing capability. Carbon fiber's inherent conjugated carbon network possesses excellent electronic conductivity, thus serving as a current collector for electrode active materials. The bonding between active materials and carbon fibers relies on their manufacturing processes, requiring optimization of their electrochemical performance and addressing the challenges of large-scale production. In this work, a LiFePO4/PEO-LiTFSI/CF composite cathode was fabricated using the direct coating method. Polyethylene oxide (PEO) acted as a binder to form a stable LiFePO4 (LFP) coating on the carbon fiber woven fabric, while multi-walled carbon nanotube (MWCNT) were employed to construct a conductive network. This significantly enhanced both the charge-discharge performance and interface stability of the composite cathode. This composite cathode achieved a first-cycle discharge-specific capacity of 133.21 mAh·g-1 at 0.1 C rate and retained 93.7% of its capacity after 200 cycles at 1 C rate. Based on this composite cathode, multiple active material coatings were integrated onto a carbon fiber woven fabric to manufacture an expandable multi-cell structural battery. Its advantage lies in the ability of multiple battery cells to disperse stress under load, thus achieving a higher capacity retention rate under bending loads. The structural battery possesses a high degree of customizability, allowing for adjustment of the area, position, and quantity of active material coatings to meet the demands of practical conditions.

碳纤维复合结构电池(SB)是一种集电化学储能与机械承载能力于一体的新型储能装置。碳纤维固有的共轭碳网络具有优异的电子导电性,可作为电极活性材料的集电流体。活性材料与碳纤维之间的粘合依赖于其制造工艺,需要优化其电化学性能并解决大规模生产的挑战。本文采用直接包覆法制备了LiFePO4/PEO-LiTFSI/CF复合阴极。聚乙烯氧化物(PEO)作为粘结剂在碳纤维织物上形成稳定的LiFePO4 (LFP)涂层,而多壁碳纳米管(MWCNT)则用于构建导电网络。这大大提高了复合阴极的充放电性能和界面稳定性。该复合阴极在0.1 C倍率下的第一次放电比容量为133.21 mAh·g-1,在1 C倍率下循环200次后仍保持93.7%的容量。基于这种复合阴极,将多种活性材料涂层集成到碳纤维编织织物上,制造出可膨胀的多电池结构电池。它的优点在于多个电池单元在负载下能够分散应力,从而在弯曲载荷下实现更高的容量保持率。结构电池具有高度的可定制性,允许调整活性物质涂层的面积、位置和数量,以满足实际条件的需求。



来源:复合材料力学仿真Composites FEM
ACTMechanicalSystemMAGNETDeform振动断裂复合材料化学航空航天核能电子通信理论材料多尺度控制
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【新文速递】2024年11月15日复合材料SCI期刊最新文章

今日更新:Composites Part A: Applied Science and Manufacturing 4 篇,Composites Part B: Engineering 11 篇Composites Part A: Applied Science and ManufacturingLiDFOB-based multifunctional electrolyte-enabled high cycling stability and rate capability of solid-state batteries for composite structural batteriesYu Fu, Yifan Chen, Hanmo Zhou, Yan Lidoi:10.1016/j.compositesa.2024.108589 复合结构电池中基于lidfob的多功能电解质高循环稳定性和倍率性能的固态电池Structural batteries have sparked widespread research interest for their potential to increase energy storage, reduce weight, and save space in electrified transportation. Achieving long-lasting performance and high rate capability is crucial for practical applications. Our work successfully developed a self-supported LiDFOB-based structural electrolyte (LSPE) thin film with exceptional tensile strength of 3.65 MPa, film formability, electrochemical stability, and ionic conductivity of 2.2 × 10-4 S cm−1. This enables solid-state Li/LiFePO4 batteries to achieve superior specific capacity of 160 mAh/g and high rate capability up to 1C. Additionally, LSPE-based multifunctional energy storage composite laminates successfully powered a hologram with a starting current of ∼ 30 mA (corresponding to ∼ 1C), demonstrating its practical feasibility. Our study offers a promising method for producing high-performance structural electrolytes for structural batteries.结构电池因其在电气化运输中增加能量储存、减轻重量和节省空间的潜力而引起了广泛的研究兴趣。实现持久的性能和高速率能力对于实际应用至关重要。我们的工作成功地开发了一种基于lidfob的自支撑结构电解质(LSPE)薄膜,其优异的抗拉强度为3.65 MPa,薄膜成形性,电化学稳定性和离子电导率为2.2 × 10-4 S cm−1。这使得固态锂/LiFePO4电池能够实现160 mAh/g的卓越比容量和高达1C的高倍率能力。此外,基于lspe的多功能储能复合材料层压板成功地以 ~ 30 mA(对应 ~ 1C)的启动电流为全息图供电,证明了其实际可行性。我们的研究为生产结构电池的高性能结构电解质提供了一种有前途的方法。Development of high-toughness aerospace composites through polyethersulfone composition optimization and mass production applicability evaluationByeong-Joo Kim, Chang-Bin Oh, Jong Sung Won, Hyung Ik Lee, Man Young Lee, Sung Hyun Kwon, Seung Geol Lee, Hyowon Park, Dong Gi Seong, Jong Min Jeong, Jeong Cheol Kimdoi:10.1016/j.compositesa.2024.108590 通过聚醚砜成分优化和量产适用性评估开发高韧性航空航天复合材料Owing to the necessity of developing airframe materials for military unmanned aerial vehicles (UAVs), capable of operating in extreme environments, aerospace-grade composite materials were developed using a high-toughness epoxy–resin system, and were subsequently analyzed and evaluated. The phase transition behavior of a high-toughness epoxy–resin system was modeled and simulated as a function of the toughening agent, polyethersulfone (PES), and its content to optimize the resin system. Reliability was ensured through experimental validation. At the maximum PES content compatible with the base epoxy–resin and curing agent contents, the epoxy–resin system exhibited the highest tensile strength and toughness. However, results from preliminary tests performed using the pilot process revealed that an increase in viscosity beyond a certain level due to the addition of PES rendered it unsuitable for application in mass-production processes. The optimal composition of the high-toughness epoxy–resin system suitable for mass production was determined based on the results of the resin paper production using the pilot process. High-toughness carbon fiber-reinforced plastics (CFRPs) were then mass produced, and their characteristics were compared with those of conventionally toughened CFRPs and the pilot products. The results confirmed that compared with the conventionally toughened CFRPs, the mass-produced CFRPs containing the high-toughness resin system showed 246%, 728%, 392% and 480% improvement in compression-after-impact strength, Mode-I interlaminar fracture toughness (ILFT), Mode-II ILFT for crack initiation, and Mode-II ILFT for crack propagation, respectively. In addition, these composites were used to manufacture UAV wings to evaluate their applicability in airframe structures.由于需要开发适用于极端环境的军用无人机(UAV)机身材料,因此开发了一种高韧性环氧树脂系统,并对其进行了分析和评估。通过将增韧剂聚醚砜(PES)及其含量作为模型变量,模拟和模拟了高韧性环氧树脂系统的相转变行为,以优化树脂系统。通过实验验证确保了可靠性。在与基体环氧树脂和固化剂含量兼容的最大PES含量下,环氧树脂系统具有最高的拉伸强度和韧性。然而,初步采用试生产工艺进行的试验结果表明,由于PES的加入导致的粘度增加,使其不适合在大规模生产过程中应用。根据试生产工艺中树脂纸生产的结果,确定了适用于大规模生产的高韧性环氧树脂系统的最优组成。随后大规模生产了高强度碳纤维增强塑料(CFRP),并比较了其特性与传统增韧CFRP和试制品的特性。结果表明,与传统增韧CFRP相比,含有高强度树脂系统的大规模生产CFRP在压缩后冲击强度、I型层间断裂韧性(ILFT)、II型ILFT(裂纹起始)和II型ILFT(裂纹扩展)方面分别提高了246%、728%、392%和480%。此外,这些复合材料被用于制造无人机机翼,以评估其在飞机结构中的适用性。Damage detection analysis of 3D braided carbon fiber composites with electro-mechanical behaviorTianwei Wu, Gen Li, Bohong Gu, Baozhong Sundoi:10.1016/j.compositesa.2024.108593 具有机电特性的三维编织碳纤维复合材料损伤检测分析The real-time detection of damage is critical for ensuring the safe application of 3D braided carbon fiber composites (3DBCFC) in both aviation and civilian sectors. In this study, we conducted an electro-mechanical behavior analysis of 3DBCFC using data processing tools to quantify various types of damage. The electro-mechanical behavior data were experimentally measured under tensile conditions. The damage detection capability of different electrical current injection methods was also experimentally validated. A mesoscale finite element model was utilized to investigate the damage mechanism of 3DBCFC under tension. Data processing tools, such as principal component analysis (PCA) and k-means clustering (k-MC), were employed to quantify the different types of damage. The study revealed that oblique current injection provided more comprehensive electrical information, making it more effective for damage detection. The electrical signals obtained through oblique current injection could be processed using data tools to quantify damage in 3DBCFC.损伤的实时检测对于确保3D编织碳纤维复合材料(3DBCFC)在航空和民用领域的安全应用至关重要。在这项研究中,我们使用数据处理工具对3DBCFC进行了机电行为分析,以量化各种类型的损伤。实验测量了拉伸条件下的电-机械行为数据。实验验证了不同电流注入方法的损伤检测能力。采用中尺度有限元模型研究了3DBCFC在拉伸作用下的损伤机理。采用主成分分析(PCA)和k-均值聚类(k-MC)等数据处理工具对不同类型的损伤进行量化。研究表明,斜电流注入提供了更全面的电气信息,使其更有效地进行损伤检测。通过斜电流注入获得的电信号可以使用数据工具进行处理,以量化3DBCFC的损伤。Thermal characterization of Xenon-Arc flash lamp heating system for automated fiber placement (AFP) of thermoplastic compositesDevang Tavkari, Vishnu V. Ganesan, Sandesh Amgai, Ankur Jain, Paul Davidsondoi:10.1016/j.compositesa.2024.108568用于热塑性复合材料纤维自动铺放(AFP)的氙弧闪光灯加热系统的热特性In this study, a systematic experimental and simulations-based characterization of key thermal aspects of the arc-flash lamp based AFP heating is presented. Ex-situ measurements of heat flux output from the flash lamp as well as the resulting temperature field on a material sample are carried out in a geometry representative of actual manufacturing conditions, using a heat flux sensor and infrared thermography. A thermal simulation model is developed to predict the temperature field resulting from the measured heat flux data. Good agreement is found between experimental data and simulation predictions. This work contributes towards developing a fundamental understanding of heat transfer processes during AFP manufacturing. Data presented here may be of broad benefit to AFP-related research, and may contribute towards process design and optimization in order to further expand the capabilities of this promising additive manufacturing technology.在这项研究中,系统的实验和基于仿真的表征电弧闪光灯的AFP加热的关键热方面。使用热流传感器和红外热成像技术,在代表实际制造条件的几何形状中对闪光灯输出的热流以及材料样品上产生的温度场进行了非原位测量。建立了一个热模拟模型来预测由实测热通量数据产生的温度场。实验数据与模拟预测吻合较好。这项工作有助于发展对AFP制造过程中传热过程的基本理解。这里提供的数据可能对afp相关的研究有广泛的好处,并可能有助于工艺设计和优化,以进一步扩大这种有前途的增材制造技术的能力。Composites Part B: EngineeringEngineered dECM-based Microsystem Promotes Cartilage Regeneration in Osteoarthritis by Synergistically Enhancing Chondrogenesis of BMSCs and Anti-inflammatory EffectYing Chen, Lin-Fei Chen, Ying Wang, You-Yu Duan, Sheng-Chang Luo, Yi-Cheng Wang, Ranjith Kumar Kankala, Shi-Bin Wang, Ai-Zheng Chendoi:10.1016/j.compositesb.2024.111974基于decm的工程微系统通过协同促进骨髓间充质干细胞的软骨形成和抗炎作用促进骨关节炎软骨再生The cartilage defects in osteoarthritis (OA) often result in loss of supporting and cushioning functionalities. Along this line, tissue engineering strategies for microfluidics based on high-precision control capabilities have been developed as promising long-term therapeutic solutions for cartilage regeneration in OA towards implementing anti-inflammatory effects and subsequent chondroprotective regeneration. In this study, an engineered microcarrier comprising composite porous microspheres based on decellularized extracellular matrix (dECM) and poly(lactic-co-glycolic acid) (PLGA) encapsulating icariin (ICA) was fabricated by microfluidic technology. This microcarrier, co-cultured with bone marrow mesenchymal stem cells (BMSCs), was developed as an injectable engineered microsystem for cartilage regeneration in OA. Mechanistically, dECM effectively repaired cartilage defects by inducing the differentiation of encapsulated stem cells to a cartilage phenotype through microenvironmental effects. In addition to enhanced secretion of active anti-inflammatory substances from BMSCs by dECM, the gradual release of ICA from the degraded PLGA PMs synergized anti-inflammatory effects in vivo, resulting in effective cartilage regeneration in OA. Utilizing a rat OA model, the engineered anti-inflammatory and regenerative microsystem significantly suppressed articular inflammation. In short, the engineered microsystem indicated favorable effects in protecting and repairing cartilage, highlighting their potential as a promising therapeutic intervention for effectively ameliorating OA.骨关节炎(OA)的软骨缺损通常导致支撑和缓冲功能的丧失。沿着这条路线,基于高精度控制能力的微流体组织工程策略已被开发为OA软骨再生的有希望的长期治疗方案,以实现抗炎作用和随后的软骨保护再生。本研究采用微流控技术制备了一种由脱细胞胞外基质(dECM)和聚乳酸-羟基乙酸(PLGA)包封淫羊藿苷(ICA)的复合多孔微球组成的工程微载体。该微载体与骨髓间充质干细胞(BMSCs)共培养,作为OA软骨再生的可注射工程微系统。在机制上,dECM通过微环境效应诱导包膜干细胞向软骨表型分化,从而有效修复软骨缺损。除了dECM增强BMSCs中活性抗炎物质的分泌外,降解的PLGA pm中ICA的逐渐释放在体内协同抗炎作用,导致OA中有效的软骨再生。利用大鼠OA模型,工程抗炎和再生微系统显著抑制关节炎症。总之,工程微系统在保护和修复软骨方面显示出良好的效果,突出了它们作为有效改善OA的有希望的治疗干预措施的潜力。Gradient-Coated Radial-Structured Scaffolds for Rapid Dural Regeneration: Providing fast migration pathways and strong migration dynamicsMin Qi, Jie Liao, Bingbing Wang, Wei He, Shuyan Liu, Shuyu Liu, Yuntao Di, Qiang Cai, Zhiwei Xu, Xiaoming Lidoi:10.1016/j.compositesb.2024.111975 用于快速硬脑膜再生的梯度涂层径向结构支架:提供快速迁移路径和强迁移动力学The unique functions of the natural dura mater necessitate the design of dural restorations with a multilayered structure to achieve multifunctionality of anti-leakage, anti-adhesion, and pro-regenerative. Due to the barrier effect of the anti-leakage or anti-adhesion layer on cells, the pro-regenerative layer repairs dural defects mainly by inducing meningeal fibroblasts at the edge of defects. Hence, constructing scaffolds that provide fast and straight migration pathways and strong migration dynamics is the key to achieving fast defect repair. In this study, a radical-structured scaffold coated with concentration-gradient acellular small intestinal submucosa (SIS) is designed and constructed. The scaffold provides a straight channel with about 75 μm of width suitable for cell invasion and strong migration dynamics caused by SIS coating. Both in vitro and in vivo experiments demonstrate its superior efficacy in promoting cellular invasion and tissue regeneration compared to random-structured scaffold. Specifically, cell migration in the scaffolds at day 14 after implantation, and collagen deposition and angiogenesis at day 28 after implantation were elevated 4.43-, 0.51-, and 2.61-fold, respectively. These enhancement effects were further improved after being coated with SIS. Consequently, this radical-structured scaffold coated with concentration-gradient SIS is promising for promoting rapid dural regeneration.天然硬脑膜的独特功能要求设计多层结构的硬脑膜修复体,以实现防渗漏、防粘连、促再生等多功能。由于抗渗漏或抗粘附层对细胞的屏障作用,促再生层主要通过在缺损边缘诱导成纤维细胞修复硬脑膜缺损。因此,构建提供快速和直接的迁移路径和强迁移动力学的支架是实现快速缺陷修复的关键。本研究设计并构建了一种浓度梯度脱细胞小肠粘膜下层(SIS)包被的根状结构支架。该支架提供了一个宽约75 μm的直通道,适合于由SIS涂层引起的细胞侵袭和强迁移动力学。体外和体内实验均证明其在促进细胞侵袭和组织再生方面优于随机结构支架。其中,植入后第14天支架内的细胞迁移量、植入后第28天的胶原沉积和血管生成量分别提高了4.43倍、0.51倍和2.61倍。经SIS包覆后,这些增强效果进一步提高。因此,这种涂有浓度梯度SIS的自由基结构支架有望促进硬脑膜的快速再生。Ultra-high energy storage efficiency achieved through the construction of interlocking microstructure and excitation of depressor effectsYuxin Hao, Yongping Pu, Jinbo Zhang, Haochen Xie, Xiang Lu, Qiao Pan, Lei Zhang, Bo Wang, Haoze Lidoi:10.1016/j.compositesb.2024.111943 通过联锁结构的构建和抑制效应的激发,实现了超高的储能效率Glass-ceramic capacitors struggle to balance high energy storage efficiency (η>90%) and sufficient breakdown field strength (Eb), hindering their use in energy storage. Interface polarization, caused by the accumulation of free charge, reduces breakdown strength. We prepared glass-ceramic materials with varying contents of the glass phase using traditional melting techniques, adjusting the glass content to enhance an interlocking structure between the glass and crystal phases, reducing Interface polarization. Divalent metal oxide BaO in the glass stimulated a depressor effect, filling gaps and increasing resistivity. The optimal composition (x=0.2) achieved a 95% energy storage efficiency and an energy storage density of 4.4 J/cm3 at 680 kV/cm, while x=0.25 reached an ultra-high energy storage efficiency of 99%. Increasing glass content reduced activation energy for Interface polarization (Ei) from 1.27 eV to 1.08 eV. Samples with x=0.2 exhibited low dielectric loss (∼0.005), high dielectric constant (∼142), ultra-high power density (∼52.8 MW/cm3), and ultra-fast discharge speed (∼26 ns), suggesting future potential for high-performance glass-ceramic materials.玻璃陶瓷电容器努力平衡高储能效率(η>90%)和足够的击穿场强(Eb)阻碍了它们在能量储存中的应用。由自由电荷积累引起的界面极化降低了击穿强度。我们使用传统的熔融技术制备了不同玻璃相含量的玻璃陶瓷材料,通过调整玻璃含量来增强玻璃和晶体相之间的联锁结构,减少界面极化。二价金属氧化物BaO在玻璃中起到抑制作用,填充空隙,提高电阻率。最优组合(x=0.2)的储能效率为95%,在680 kV/cm下的储能密度为4.4 J/cm3,而x=0.25的超高储能效率为99%。增加玻璃含量降低了界面极化活化能(Ei)从1.27 eV到1.08 eV。x=0.2的样品表现出低介电损耗(~ 0.005)、高介电常数(~ 142)、超高功率密度(~ 52.8 MW/cm3)和超快放电速度(~ 26 ns),表明高性能玻璃陶瓷材料的未来潜力。Microchannels-enabled Vertical Alignment of Hexagonal Boron Nitride in Silicone Rubber Composites to Achieve High Through-plane Thermal ConductivityYuan Ji, Chunhai Li, Hong Wu, Shaoyun Guo, Fengshun Zhang, Jianhui Qiudoi:10.1016/j.compositesb.2024.111965硅橡胶复合材料中六方氮化硼的微通道垂直排列以实现高通平面导热性Hexagonal boron nitride (h-BN) with high vertical alignment in polymer composites is necessary to improve through-plane thermal conductivity (TC) for thermal management applications. However, how to achieve simple, efficient and precise control of h-BN vertical alignment in polymer composites remains a challenge. Herein, a novel concept of inducing vertical alignment of h-BN in silicone rubber (SR) composites via controlling flow patterns in specially designed microchannels was proposed. The extremely strong elongational and shear stresses provided by the narrow section of the microchannels induced h-BN to align perpendicular to the flow direction. In the subsequent channel, the weak shear stress manipulated h-BN to form a ladder structure in the SR composites, including the vertical core layer and horizontal skin layer. Such ladder structure not only improved the through-plane TC of SR composite but also prevented overheating in the face of local heat sources. Moreover, the obtained SR composites exhibit a through-plane TC of 5.08 W/mK at 34.3 vol % h-BN loading when the horizontal skin layer was removed, indicating excellent heat transfer efficiency for thermal management application. We believe that this work would strengthen both scientific and technological cognition of the filler alignment during polymer composites processing.高垂直取向的六方氮化硼(h-BN)是提高聚合物复合材料通过面导热性(TC)的必要材料。然而,如何实现聚合物复合材料中h-BN垂直取向的简单、高效和精确控制仍然是一个挑战。本文提出了一种通过控制特殊设计的微通道中的流动模式来诱导h-BN在硅橡胶(SR)复合材料中垂直排列的新概念。窄截面微通道提供的极强的拉伸和剪切应力诱导h-BN垂直于流动方向排列。在随后的通道中,弱剪切应力操纵h-BN在SR复合材料中形成阶梯结构,包括垂直的核心层和水平的表皮层。这种阶梯式结构既提高了SR复合材料的通面温度,又防止了在局部热源面前的过热。此外,在34.3%体积%的h-BN负载下,去除水平蒙皮层时,所获得的SR复合材料的通平面TC为5.08 W/mK,表明其具有良好的传热效率,可用于热管理应用。我们相信,这一工作将加强对聚合物复合材料加工过程中填料排列的科学和技术认识。Autologous myokine-loaded pre-vascularized bioactive scaffold enhances bone augmentationChunhui Wang, Yonghao Qiu, Yulian Yang, Qiyuan Dai, Xiaodong Cao, Longquan Shao, Fujian Zhaodoi:10.1016/j.compositesb.2024.111967 自体肌因子负载预血管化生物活性支架增强骨增强The poor angiogenic ability is the main reason for the failure of bone augmentation material implantation. Pre-vascularized culture is considered to be an effective method to accelerate early angiogenesis, while the immune rejection has limited clinical application. Herein, since bone augmentation is an elective procedure, an easily accessible pre-vascularized silk fibroin/bioactive glass (SF-BG) scaffold without immune rejection was prepared by autologous intramuscular implantation. The SF-BG scaffolds exhibited outstanding vascularization ability in muscle by enhancing the muscle endocrine function. Further mechanism study confirmed that BG improved the synthesis and secretion of myokine irisin by regulating PI3K/Akt/PGC-1α/FNDC5 signaling pathway. After implantation in the bone augmentation position, the pre-vascularized BG scaffold with irisin loaded fostered the early angiogenesis of implantation and increased bone augmentation at the late stage. This study proposed a new idea for bone augmentation by autologous intramuscular pre-vascularized scaffolds.血管生成能力差是骨增强材料植入失败的主要原因。预血管化培养被认为是促进早期血管生成的有效方法,而免疫排斥反应的临床应用有限。在此,由于骨增强是一种选择性手术,因此通过自体肌内植入制备了一种易于获取且无免疫排斥反应的预血管化丝素/生物活性玻璃(SF-BG)支架。SF-BG支架通过增强肌肉内分泌功能,表现出良好的肌肉血管化能力。进一步的机制研究证实,BG通过调节PI3K/Akt/PGC-1α/FNDC5信号通路,促进了肌因子鸢尾素的合成和分泌。在骨增强位植入后,载鸢尾素的预血管化BG支架促进了植入体早期血管生成和后期骨增强。本研究提出了自体肌内预血管化支架骨增强的新思路。Ultra-lightweight asymmetric hierarchical porous structure for high-efficiency absorption-dominated electromagnetic interference shieldingPengcheng Zhang, Haiyang Li, Haoyu Liang, Huanping Wang, Xiangkun Shan, Yuhang Wang, Xiaoyu Fan, Ke Xu, Qiuyu Zhang, Yanhui Chendoi:10.1016/j.compositesb.2024.111969超轻型非对称分层多孔结构,用于高效吸收为主的电磁干扰屏蔽In this work, ultra-lightweight composite aerogels with a hierarchical pore structure consisting of hollow Fe3O4 microspheres (∼250 nm), hollow MXene microspheres (∼580 nm) and pores (10–40 μm) in polyimide (PI) aerogel are developed through directional freezing, followed by freeze drying and thermal annealing. The composite aerogels exhibit a distinct asymmetric structure, with a top Fe3O4/PI aerogel layer designed for impedance matching and a bottom MXene/PI aerogel layer aimed at enhancing attenuation. This deliberate structure design not only reduces the density of the composite aerogels but also greatly enhances their absorption of electromagnetic waves. The composite aerogel demonstrates an impressive X-band EMI SE of 69.7 dB, a remarkable absorption coefficient (A) of 0.73, and an excellent surface-specific SE (SE divided by material density and thickness) of 13352 dB cm2 g−1, achieved at a density of just 0.034 g/cm³. Moreover, the composite aerogel exhibits outstanding stability in compression and shielding performance. Following 100 cycles of compression, the compressive strength remains at 94.9 % of the initial compressive strength (98 kPa), and its EMI SE maintains 68.5 dB with a retention rate of 98.2 %. Additionally, the composite aerogel presents outstanding thermal insulation (0.046 W m−1 K−1) and thermal resistance (initial decomposition temperature > 500 °C). This work provides novel insights into the design and fabrication of ultra-lightweight and absorption-dominated EMI shielding materials.在这项工作中,通过定向冷冻,然后冷冻干燥和热退火,开发了具有分层孔隙结构的超轻质复合气凝胶,该气凝胶由中空Fe3O4微球(~ 250 nm),中空MXene微球(~ 580 nm)和聚酰亚胺(PI)气凝胶中的孔隙(10-40 μm)组成。复合气凝胶表现出明显的不对称结构,顶部的Fe3O4/PI气凝胶层用于阻抗匹配,底部的MXene/PI气凝胶层旨在增强衰减。这种精心设计的结构不仅降低了复合气凝胶的密度,而且大大增强了复合气凝胶对电磁波的吸收。复合气凝胶的x波段EMI SE为69.7 dB,吸收系数(a)为0.73,表面比SE (SE除以材料密度和厚度)为13352 dB cm2 g−1,密度仅为0.034 g/cm³。此外,复合气凝胶在压缩和屏蔽性能方面表现出优异的稳定性。经过100次循环压缩后,抗压强度保持在初始抗压强度(98 kPa)的94.9%,EMI SE保持在68.5 dB,保留率为98.2%。此外,复合气凝胶具有良好的绝热性(0.046 W m−1 K−1)和耐热性(初始分解温度> 500℃)。这项工作为超轻量和吸收为主的电磁干扰屏蔽材料的设计和制造提供了新的见解。An injectable antibacterial wet-adhesive for meniscal cartilage regeneration via immune homeostasis mediated by SMSC-derived extracellular vesiclesMoran Huang, Zhengchao Yuan, Guojian Fu, Jize Dong, Yaying Sun, Wenxin Wang, Muhammad Shafiq, Huiliang Cao, Xiumei Mo, Jiwu Chendoi:10.1016/j.compositesb.2024.111970通过smsc来源的细胞外囊泡介导的免疫稳态介导的半月板软骨再生的可注射抗菌湿胶Surgical repair is recommended for meniscus tear to avoid knee degeneration. However, postoperative meniscal healing remains challenging due to limited blood supply, particularly the avascular zone. Tissue-engineering techniques had limited outcomes in meniscus repair due to the highly irregular interface of meniscus and the wet joint environment. Additionally, it was proved that the inflammation status and the recruitment of endogenous cells are crucial for meniscal healing. This study represents a versatile extracellular vesicles (EVs)-based wet-adhesive employed in meniscus repair. A novel injectable hydrogel adhesive, designated as oxidized dextran/carboxymethyl chitosan/poly-L-lysine/synovial mesenchymal stem cell-derived EVs (OD/CS-PL@EVs), was fabricated and demonstrated effective antibacterial activity against S. aureus and E. coli. This adhesive also exhibited effective adhesion to the waterish meniscus with a lap shear strength of 134 KPa. Additionally, it promoted the proliferation, migration, chondrogenic differentiation, and extracellular matrix formation of SMSCs and meniscus cells and induced the polarization of macrophages towards the M2 phenotype in vitro. The RNA sequencing results further proved that four inflammation-related signaling pathways were inhibited by the prepared products. After being administered into the rabbit meniscal defect model, OD/CS-PL@EVs hydrogel adhesive effectively regulated the inflammatory balance and facilitated the meniscal cartilage regeneration in the avascular area, further remarkably delaying the progression of osteoarthritis. In summary, OD/CS-PL@EVs hydrogel adhesive provided a promising strategy to promote meniscal repair in avascular zone repair of meniscus for future clinical applications, holding great potential in preventing osteoarthritis.半月板撕裂建议手术修复,以避免膝关节退变。然而,由于血液供应有限,特别是无血管区,半月板术后愈合仍然具有挑战性。由于半月板和潮湿关节环境的界面高度不规则,组织工程技术在半月板修复中的效果有限。此外,研究证明炎症状态和内源性细胞的募集对半月板愈合至关重要。本研究介绍了一种多功能细胞外囊泡(ev)基湿胶用于半月板修复。制备了氧化葡聚糖/羧甲基壳聚糖/聚l- lysine/滑膜间充质干细胞衍生EVs (OD/CS-PL@EVs)的新型可注射水凝胶粘合剂,并对金黄色葡萄球菌和大肠杆菌具有有效的抗菌活性。该胶粘剂对水性半月板也有较好的粘接效果,其搭接抗剪强度可达134 KPa。此外,它还能促进SMSCs和半月板细胞的增殖、迁移、成软骨分化和细胞外基质的形成,并诱导巨噬细胞向M2表型极化。RNA测序结果进一步证明,制备的产物抑制了四种炎症相关的信号通路。OD/CS-PL@EVs水凝胶粘接剂给药兔半月板缺损模型后,有效调节炎症平衡,促进半月板无血管区软骨再生,进一步显著延缓骨关节炎的进展。综上所述,OD/CS-PL@EVs水凝胶粘接剂在半月板无血管区修复中促进半月板修复为未来的临床应用提供了一种很有前景的策略,在预防骨关节炎方面具有很大的潜力。Personalized customization of in-plane thermal conductive networks by a novel electrospinning methodWei-Hua Han, Qing-Yu Wang, Yu Long, Meng Xin, Yun-Ze Long, Chun-Cheng Haodoi:10.1016/j.compositesb.2024.111971基于新型静电纺丝方法的面内导热网络个性化定制Using one-dimensional (1D) nanofibers to induce the assembly of two-dimensional (2D) nanosheets is of great practical significance; naturally, electrospinning, as the most effective method to prepare long nanofibers, has attracted widespread attention. In this paper, a novel electrospinning method that can induce the directional deposition of nanofibers through electrode arrays has been proposed, optimized, and further applied to regulate the aligned assembly of boron nitride nanosheets (BNNSs) to prepare highly thermally conductive and electrically insulating polyvinylidene fluoride (PVDF)/BNNS composites. In particular, the intermittent-contact collection mode of electrospun nanofibers has further enriched the electrospinning system. The composites prepared by our strategy possess high in-plane thermal conductivity (18.86 W/(m·K)), volume resistivity (nearly 1015 Ω·cm), and breakdown strength (nearly 380 kV/mm). Furthermore, excellent mechanical properties, flexibility, and thermal conduction capability are vividly demonstrated. The proposed electrospinning method and the prepared PVDF/BNNS composites have great potential in the thermal management application of electronic devices in the 5G era.利用一维(1D)纳米纤维诱导二维(2D)纳米片的组装具有重要的现实意义;静电纺丝作为制备长纳米纤维最有效的方法,自然受到了广泛的关注。本文提出了一种新的静电纺丝方法,通过电极阵列诱导纳米纤维定向沉积,并对其进行了优化,并进一步应用于调控氮化硼纳米片(BNNSs)的排列组装,以制备高导热、高绝缘的聚偏氟乙烯(PVDF)/BNNS复合材料。特别是电纺丝纳米纤维的间歇接触收集方式,进一步丰富了电纺丝体系。通过我们的策略制备的复合材料具有较高的面内导热系数(18.86 W/(m·K)),体积电阻率(接近1015 Ω·cm)和击穿强度(接近380 kV/mm)。此外,还表现出优异的机械性能、柔韧性和导热性能。所提出的静电纺丝方法和制备的PVDF/BNNS复合材料在5G时代电子器件的热管理应用中具有很大的潜力。Towards scarless repair: MMP-2 responsive drug releasing nanofibrous mat restores homeostasis via fibroblasts’ activationWei Nie, Eric J. Marrotte, Rongyuan Xie, Hans-Günther Machens, Arndt F. Schilling, Yi Shen, Michael Seeds, Anthony Atala, Xinyi Daidoi:10.1016/j.compositesb.2024.111972 迈向无疤痕修复:MMP-2反应性药物释放纳米纤维垫通过成纤维细胞的激活恢复体内平衡The failure of wound repair, particularly in cases of refractory wounds, is closely associated with immune disorders, leading to serious consequences such as scarring and ulcers. To address this issue, Poly [octanediol-co- (citric acid)] (POCA)/gelatin curcumin-loaded nanofibrous mats responsive to inflammatory microenvironments are developed. POCA serves as a cross-linker for gelatin, providing the nanofibrous mat with skin-like J-shaped stress-strain behavior. Moreover, the pendant carboxyl groups of POCA enable adhesion ability in the wet state, thereby increasing wound sealing. Most importantly, the as-prepared nanofibers are sensitive to MMP-2. Amorphous curcumin is responsively released in response to high MMP levels present in inflammatory wounds. This significantly enhances curcumin's efficiency. The mat exhibits substantial therapeutic effects on chronic diabetic wounds and tension-loaded wounds, nudging wound healing toward regenerative repair. Moreover, it was also shown to promote basement membrane renewal by activating wound fibroblasts, which mitigates the immune response and reinstate homeostasis.伤口修复失败,特别是难治性伤口的修复失败,与免疫功能紊乱密切相关,导致结疤和溃疡等严重后果。为了解决这个问题,聚辛二醇-柠檬酸(POCA)/明胶姜黄素负载纳米纤维垫对炎症微环境有反应。POCA作为明胶的交联剂,为纳米纤维垫提供了类似皮肤的j形应力-应变行为。此外,POCA的垂坠羧基使其在湿润状态下具有粘附能力,从而增加了伤口的密封性。最重要的是,制备的纳米纤维对MMP-2敏感。无定形姜黄素在炎性伤口中对高MMP水平的反应性释放。这大大提高了姜黄素的效率。该材料对慢性糖尿病伤口和张力伤口有显著的治疗作用,促进伤口愈合向再生修复方向发展。此外,它还被证明通过激活伤口成纤维细胞来促进基底膜的更新,从而减轻免疫反应并恢复体内平衡。Exceptional Damping of CFRPs: Unveiling the Impact of Carbon Fiber Surface TreatmentsJigang Feng, Chuang Gao, Babak Safaei, Zhaoye Qin, Haihong Wu, Fulei Chu, Fabrizio Scarpadoi:10.1016/j.compositesb.2024.111973 碳纤维纤维的特殊阻尼:揭示碳纤维表面处理的影响A significant body of research has concentrated on augmenting the interfacial slippage between carbon fiber (CF) fabrics and resin to improve the damping properties of CF reinforced plastics (CFRPs). However, a critical but commonly overlooked issue lies in the fact that a higher number of mutual slippage interfaces may lead to potential debonding at the interface. This, in turn, not only influences mechanical properties but also escalates the risk of structural damage. In this study, three distinct modification methods are proposed to alter the surface characteristics of CFs, achieving simultaneous enhancement of the damping and mechanical properties of CFRPs. Specifically, the polymerization of dopamine on the CF surface results in CFRPs with a loss factor of 0.227 at 1 Hz, which is 180% higher than the 0.081 of referenced CFRP. Additionally, using this modification method, the tensile modulus and strength of the CFRP are increased by about 11.3% and 6.7%, respectively. More importantly, the subtle relationships within the CFRPs interface are explored through the different surface modification methods. The interactions between surface wettability, specific surface area, roughness, and interfacial chemical bonding on the mechanical and damping properties are redefined and elucidated. This study demonstrates that surface modification can simultaneously enhance both the damping and mechanical properties of CFRPs, and a satisfactory balance of multiple enhancement effects can be achieved by adjusting the surface modification factors.通过增加碳纤维织物与树脂之间的界面滑移来改善碳纤维增强塑料(CFRPs)的阻尼性能,已成为国内外研究的热点。然而,一个关键但通常被忽视的问题在于,较高数量的互滑界面可能导致界面上潜在的脱粘。反过来,这不仅会影响机械性能,还会增加结构损坏的风险。在本研究中,提出了三种不同的改性方法来改变碳纤维的表面特性,从而同时增强碳纤维的阻尼和力学性能。具体来说,多巴胺在CF表面的聚合导致CFRP在1 Hz时的损耗因子为0.227,比参考CFRP的0.081高出180%。改性后CFRP的拉伸模量和强度分别提高了约11.3%和6.7%。更重要的是,通过不同的表面改性方法,探索了CFRPs界面内部的微妙关系。重新定义和阐明了表面润湿性、比表面积、粗糙度和界面化学键对机械和阻尼性能的相互作用。研究表明,表面改性可以同时增强碳纤维纤维的阻尼性能和力学性能,并且通过调整表面改性因子可以实现多种增强效果的良好平衡。Nitrogen-doped porous carbon skeleton derived from glycine boosting superior rate capability and long lifespan for Na3V2(PO4)3 with high thermal safetyRui Du, Changcheng Liu, Que Huang, Baofeng Zhang, Hongyuan Ding, Jianghui Xie, Shengnan He, Yaxiong Yang, Chao Zheng, Yanjun Chendoi:10.1016/j.compositesb.2024.111977 甘氨酸衍生的氮掺杂多孔碳骨架提高了Na3V2(PO4)3的优越速率性能和长寿命,具有高热安全性Currently, the both low electronic and ionic conductivity have seriously hindered the further application of Na3V2(PO4)3 (NVP). Nevertheless, traditional carbon materials modification only improves the electronic conductive property, rather than modifying the ionic conductivity. Herein, N-rich carbon resources of glycine (GLY) is introduced to synthesize NVP, which can act as reducing agent and morphology inducer to optimize NVP sample. Notably, GLY supplies favourable N-doped carbon skeleton, and this defective carbon structure benefits for the accelerated electronic conductivity. Besides, porous construction is established after introducing GLY. This unique morphology significantly improves the infiltration effects of electrolyte, thus providing more electrochemical active sites for Na+ de-intercalation to improve the ionic conductivity. Meanwhile, porous framework supplies enough space for the shrinkage of crystal cells, so the stress-strain effect is highly restrained, which is demonstrated by Ex-situ XRD. The stabilized crystal and morphological structure of NVP@GLY-2 has been verified by after-cycled XRD/SEM/XPS. Highly improved kinetic characteristics are also investigated by In-situ EIS. Moreover, Accelerating Rate Calorimeter (ARC) measurements indicate that NVP@GLY-2-based half and full cells also have excellent thermal safety properties. Comprehensively, NVP@GLY-2 reveals a high capacity of 119 mAh g-1 at 0.1 C. It reveals 84.5 and 71.2 mAh g-1 at 10 and 50 C, with capacity retention rates of 88.9% and 85.8% after 1000 cycles.目前,Na3V2(PO4)3 (NVP)的电子电导率和离子电导率均较低,严重阻碍了其进一步应用。然而,传统的碳材料改性只能提高其电子导电性,而不能改变其离子电导率。本文引入富n碳源甘氨酸(GLY)合成NVP,作为还原剂和形态诱导剂对NVP样品进行优化。值得注意的是,GLY提供了有利的n掺杂碳骨架,这种缺陷的碳结构有利于加速电子导电性。此外,引入GLY后,建立了多孔结构。这种独特的形态显著提高了电解质的渗透效果,从而为Na+脱插提供了更多的电化学活性位点,从而提高离子电导率。同时,多孔骨架为晶胞的收缩提供了足够的空间,因此应力-应变效应受到了高度的抑制。通过后循环XRD/SEM/XPS验证了NVP@GLY-2稳定的晶体结构和形态结构。通过原位EIS研究了高改进的动力学特性。此外,加速速率量热计(ARC)测量表明NVP@GLY-2-based半电池和全电池也具有优异的热安全性能。综合而言,NVP@GLY-2在0.1℃时显示出119 mAh g-1的高容量,在10℃和50℃时显示出84.5和71.2 mAh g-1,在1000次循环后容量保持率分别为88.9%和85.8%。来源:复合材料力学仿真Composites FEM

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