【新文速递】2024年4月6日复合材料SCI期刊最新文章

   

今日更新：Composite Structures 8 篇，Composites Part A: Applied Science and Manufacturing 2 篇，Composites Part B: Engineering 3 篇，Composites Science and Technology 2 篇

Composite Structures

Deep learning uncertainty quantification for ultrasonic damage identification in composite structures

Houyu Lu, Sergio Cantero Chinchilla, Xin Yang, Konstantinos Gryllias, Dimitrios Chronopoulos

doi:10.1016/j.compstruct.2024.118087

复合材料结构超声波损伤识别的深度学习不确定性量化

In this paper, three state-of-the-art deep learning uncertainty quantification (UQ) methods —Flipout probabilistic convolutional neural network (CNN), deep ensemble probabilistic CNN, and Bayesian probabilistic CNN—based on the Visual Geometry Group 13 architecture are proposed. They are compared with a traditional Bayesian inference approach for localizing delamination damage in composite. The law of conditional covariance is used to separate and quantify the predictive variance of the three networks into aleatoric and epistemic uncertainty. The network models’ performance is enhanced through hyperparameter optimization using Hyperband and warm-up optimization algorithms. The performance of the three networks in measuring the uncertainty is assessed on an out-of-distribution (OOD) dataset and validated on an in-distribution (ID) dataset for localization of composite delamination damage. Results indicate high accuracy in predicting damage locations for all methods on the ID dataset. On the OOD dataset, the Flipout and deep ensemble network have better performance, stably measuring aleatoric uncertainty in both trained and untrained areas, while the Bayesian network’s aleatoric uncertainty shows a discernible change across both areas. All three networks effectively measure epistemic uncertainty. Overall in both ID and OOD datasets, the Flipout network provides an optimal balance among training efficiency, UQ effectiveness and accuracy in predicting damage locations.

本文基于 Visual Geometry Group 13 架构，提出了三种最先进的深度学习不确定性量化（UQ）方法--Flipout 概率卷积神经网络（CNN）、深度集 合概率 CNN 和贝叶斯概率 CNN。它们与传统的贝叶斯推理方法进行了比较，以定位复合材料中的分层损伤。利用条件协方差定律将这三种网络的预测方差分为不确定性和认识不确定性，并对其进行量化。通过使用 Hyperband 和预热优化算法进行超参数优化，提高了网络模型的性能。在一个分布外（OOD）数据集上评估了三个网络在测量不确定性方面的性能，并在一个分布内（ID）数据集上验证了复合材料分层损伤定位的性能。结果表明，在 ID 数据集上，所有方法预测损伤位置的准确性都很高。在 OOD 数据集上，Flipout 和深度集 合网络具有更好的性能，可以稳定地测量训练区域和未训练区域的不确定性，而贝叶斯网络的不确定性在两个区域都有明显的变化。这三个网络都能有效测量认识不确定性。总体而言，在 ID 和 OOD 数据集中，Flipout 网络在训练效率、UQ 效果和预测损坏位置的准确性之间实现了最佳平衡。

An experimental and parametrical study on repair of cracked titanium airframe structures with single-side bonded carbon fiber-reinforced polymer prepreg patches

Junshan Hu, Ruihao Kang, Jinrong Fang, Shizhan Chen, Shanyong Xuan, Jian Zhou, Wei Tian

doi:10.1016/j.compstruct.2024.118102

使用单面粘接碳纤维增强聚合物预浸料修补剂修复开裂钛机身结构的实验和参数研究

The present research aims to investigate efficient repair techniques of cracked Ti-alloy aircraft structures with adhesively bonded carbon fiber-reinforced polymer prepreg patches. The repaired specimens in the configuration of a Ti-alloy butt joint with one-side bonded composite patch were prepared under multiple repair factors including patch thickness, patch length, adhesive thickness, cure pressure, patch layup and surface treatment. The repair efficiency was evaluated by loading behavior, bonded interface microstructure and failure mode. The results reveals that the geometric factors affect the loading performance and alter failure modes by adjusting stress distribution in the repair system, whereas the cure pressure and surface treatment act on the bondline and change interfacial properties. A sensitivity-optimization model based on analysis of variance was established for parametrical study to quantify the contribution of repair factors and obtain optimal values. The optimum parameters were validated by repaired central-cracked specimens via static and fatigue tests, which proved that the repaired structure could restore 90.7% loading capacity of intact ones and endure more than 106 fatigue cycles of 25% ultimate failure load level of center-cracked ones. The proposed experimental and parametrical study possessed good efficacy in refurbishing strength and stiffness of cracked metallic structures.

本研究旨在探讨使用粘合碳纤维增强聚合物预浸料补片对开裂的钛合金飞机结构进行高效修复的技术。在多种修复因素（包括贴片厚度、贴片长度、粘合剂厚度、固化压力、贴片铺设和表面处理）的作用下，制备了钛合金对接接头与单面粘合复合材料贴片的修复试样。通过加载行为、粘接界面微观结构和失效模式对修复效率进行了评估。结果表明，几何因素通过调整修复系统中的应力分布影响加载性能并改变破坏模式，而固化压力和表面处理则作用于粘合线并改变界面特性。在参数研究中建立了基于方差分析的敏感性优化模型，以量化修复因素的贡献并获得最优值。修复后的中心裂纹试样通过静态和疲劳试验验证了最佳参数，证明修复后的结构可恢复完整试样 90.7% 的承载能力，并可承受中心裂纹试样 25% 极限破坏载荷水平的 106 次以上疲劳循环。所提出的实验和参数研究在修复开裂金属结构的强度和刚度方面具有良好的效果。

Study on the performance of aluminum matrix ceramic ball composite materials plate for hypervelocity impact protection based on FE-SPH adaptive method

YJ. Deng, YF. Ren, X. Liu, L. Li, M. Qin

doi:10.1016/j.compstruct.2024.118103

基于 FE-SPH 自适应方法的超高速冲击防护铝基陶瓷球复合材料板性能研究

Space debris is a major threat to the safety of spacecraft in orbit, and advanced protective materials with lightweight and high impact resistance are effective passive protection solutions. In order to investigate the hypervelocity impact protection performance of aluminum matrix ceramic ball composite materials plate, this paper has carried out the hypervelocity impact test of aluminum matrix ceramic ball composite materials plate, and verified the accuracy of the numerical model based on the FE-SPH adaptive method, and then carried out a comparative study on the hypervelocity impact protection performance of aluminum plate and aluminum matrix ceramic ball composite materials plate with the same area density. The results show that: compared with the aluminum plate conditions, the composite materials target has a better ability to broken the projectile. Compared with the aluminum target, the kinetic energy absorbed by the composite target is increased by 37.04%, and the kinetic energy of the generated debris cloud decreased by 69.57. The proportion of the internal energy dissipation of the composite materials impact system reaches up to 72.03%. The secondary pollution generated by the composite target is less and the hazardous debris have less threat to the rear wall. The research in this paper can provide reference for the selection of hypervelocity impact protection materials.

空间碎片是在轨航天器安全的主要威胁，轻质高抗冲击的先进防护材料是有效的被动防护解决方案。为了研究铝基陶瓷球复合材料板的超高速撞击防护性能，本文进行了铝基陶瓷球复合材料板的超高速撞击试验，验证了基于FE-SPH自适应方法的数值模型的准确性，进而对相同面积密度的铝板和铝基陶瓷球复合材料板的超高速撞击防护性能进行了对比研究。结果表明：与铝板条件相比，复合材料靶具有更好的破射能力。与铝靶相比，复合材料靶吸收的动能增加了 37.04%，产生的碎片云动能减少了 69.57。复合材料冲击系统的内能耗散比例高达 72.03%。复合材料靶材产生的二次污染较少，有害碎片对后壁的威胁较小。本文的研究可为超高速撞击防护材料的选择提供参考。

A new guided mode so-called minimum group velocity in viscoelastic sandwich plates: A parametric numerical study

Souhail Dahmen, Cherif Othmani, Sebastian Merchel, M. Ercan Altinsoy, Abir Rouis, Jian Xiong, Farid Takali

doi:10.1016/j.compstruct.2024.118106

粘弹性夹层板中所谓最小群速度的新引导模式：参数数值研究

Zero-Group-Velocity (ZGV) guided mode has recently received particular attention because of its highly sensitive to structural changes, such as defects. Parallel to ZGV, in the present work, we introduce a new guided mode so-called Minimum-Group-Velocity (MGV) that is a remarkable phenomenon in defect detection applications. Strictly speaking, when any two phase-velocity dispersion curves of Lamb modes approach each other without overlapping, we observe this new mode in group-velocity dispersion curves. It is worth noting that this MGV mode has never been addressed in literature. We compute the Lamb-like modes in asymmetric viscoelastic sandwich plates using the Stiffness Matrix Method (SMM). We show that the change in properties of this sandwich can dramatically affect frequency ranges associated with ZGV and MGV modes. However, a linear correlation between phase velocities and this change on viscoelastic properties is discussed, where we observed an interconnection phenomenon in the dispersion curves. This interconnection happens between specific points on the dispersion curves, each corresponding to a ZGV- or MGV-mode. On the other hand, we verify that the detection of changes in level of viscoelastic properties or variations in the thickness of the buffer viscoelastic layer is possible within a limited segment of the damped mode curve.

零群速度（ZGV）制导模式因其对结构变化（如缺陷）的高度敏感性最近受到了特别关注。与 ZGV 同时，我们在本研究中引入了一种新的导波模式，即最小群速度（MGV），它在缺陷检测应用中是一种显著现象。严格来说，当任何两个 Lamb 模式的相位速度频散曲线相互接近而不重叠时，我们就能在群速度频散曲线中观察到这种新模式。值得注意的是，这种 MGV 模式从未在文献中出现过。我们使用刚度矩阵法（SMM）计算了非对称粘弹性夹层板中的类 Lamb 模式。结果表明，夹层性质的改变会极大地影响与 ZGV 和 MGV 模式相关的频率范围。然而，我们讨论了相位速度与粘弹特性变化之间的线性相关关系，并观察到频散曲线中的互连现象。这种相互连接发生在频散曲线上的特定点之间，每个点都对应一个 ZGV 或 MGV 模式。另一方面，我们验证了在阻尼模式曲线的有限段落内检测粘弹性特性水平的变化或缓冲粘弹性层厚度的变化是可能的。

A coupled 3D morphological reconstruction method for point microcrack defects in Si3N4 ceramic bearing rollers

Dahai Liao, Jianfei Yang, Xianqi Liao, Weiwen Hu, Jiao Li, Nanxing Wu

doi:10.1016/j.compstruct.2024.118107

Si3N4 陶瓷轴承滚子点状微裂纹缺陷的耦合三维形态重建方法

The features of shallow depth and gradual blurring are characterized by the point microcrack defects in Si3N4 ceramic bearing rollers. Point clouds accuracy and mesh correctness of 3D morphological reconstruction are affected. A coupled method is proposed for reconstructing the 3D morphology, based on small-scale structure from motion and nonlinear image clustering vision. The fine-tuning motion supply system is designed based on the shallow depth characteristics of point microcrack defects. The sparse point clouds of point microcrack defects are obtained. The gradually blurring of the point microcrack defects is analyzed. Thus, the nonlinear image clustering and convergence functions are established. The dense point clouds and texture mesh of point microcrack defects are reconstructed. The experimental results show the diameter of the circular region containing the point microcrack defects is 17.798 μm. The maximum local longitudinal span of the point microcrack defects is 239 nm. The number of sparse point clouds vertex, dense point clouds vertex and texture mesh face is 535, 13206, 21086, respectively. The reconstructed results are in well agreement with the raw image segmentation results. The theoretical basis for the research on the mechanism of point microcrack defects propagation and the prediction of bearing life is provided.

Si3N4 陶瓷轴承滚子的点状微裂纹缺陷具有深度浅、逐渐模糊的特征。三维形态重建的点云精度和网格正确性受到影响。本文提出了一种基于运动小尺度结构和非线性图像聚类视觉的三维形态重建耦合方法。根据点状微裂纹缺陷的浅深度特征，设计了微调运动供给系统。获得了点状微裂纹缺陷的稀疏点云。分析了点状微裂纹缺陷的逐渐模糊现象。从而建立了非线性图像聚类和收敛函数。重建了点状微裂纹缺陷的稠密点云和纹理网格。实验结果表明，包含点状微裂纹缺陷的圆形区域直径为 17.798 μm。点状微裂纹缺陷的最大局部纵向跨度为 239 nm。稀疏点云顶点、密集点云顶点和纹理网格面的数量分别为 535、13206 和 21086。重建结果与原始图像分割结果完全一致。为研究点状微裂纹缺陷传播机理和预测轴承寿命提供了理论依据。

Meso-FE modelling for homogenization of the nonlinear orthotropic behavior of PTFE-coated fabric based on virtual fiber method

Junhao Xu, Yan Zhang, Yingying Zhang, Wei Song, Hao Xu, Yushuai Zhao

doi:10.1016/j.compstruct.2024.118093

基于虚拟纤维法的用于 PTFE 涂层织物非线性各向同性行为均质化的 Meso-FE 模型

Compared to traditional textile composites, the coated fabric used in fabric membrane structures is much more flexible. Its macroscopic mechanical behavior is highly nonlinear, anisotropic, and shows stress ratio dependence during the loading process. The main reason is that the yarns within the coated fabric are not completely solidified, and there is a significant crimp interchange process in the yarns under load. This paper proposes a novel mesoscopic finite element (FE) model to predict the nonlinear orthotropic mechanical behavior of PTFE-coated fabric using the virtual fiber method (VFM). By comparing with experimental data, it is shown that the virtual fiber defined by the truss element can visually and effectively simulate the mechanical behavior of the internal fibers and reflect the crimp interchange process between two-way yarns. Combined with PBCs, it can effectively predict the uniaxial and biaxial tensile behaviors of the PTFE-coated fabric. Moreover, a new multi-scale model suitable for structural scale analysis of fabric membrane structures has been attempted by combining the direct FE2 (D-FE2) method with the proposed mesoscopic FE model. Local deformation mechanisms and macro response of fabric membrane structures can be observed simultaneously from these analyses, which provide a better understanding of the mechanical behavior of the fabric membrane structures.

与传统的纺织复合材料相比，织物膜结构中使用的涂层织物要柔韧得多。它的宏观机械行为高度非线性、各向异性，并在加载过程中表现出应力比依赖性。其主要原因是涂层织物中的纱线没有完全凝固，在加载过程中纱线存在明显的卷曲交换过程。本文提出了一种新型介观有限元（FE）模型，利用虚拟纤维法（VFM）预测 PTFE 涂层织物的非线性各向同性力学行为。通过与实验数据的比较，表明由桁架元素定义的虚拟纤维能直观有效地模拟内部纤维的力学行为，并反映双向纱线之间的卷曲交换过程。结合 PBC，它能有效预测 PTFE 涂层织物的单轴和双轴拉伸行为。此外，通过将直接 FE2（D-FE2）方法与所提出的介观 FE 模型相结合，尝试了一种适用于织物膜结构尺度分析的新型多尺度模型。通过这些分析，可以同时观察到织物膜结构的局部变形机制和宏观响应，从而更好地理解织物膜结构的力学行为。

Hybridization of face sheet in sandwich composites to mitigate low temperature and low velocity impact damage

Jason P. Mack, Faizan Mirza, Arnob Banik, M.H. Khan, K.T. Tan

doi:10.1016/j.compstruct.2024.118101

夹层复合材料中的面片杂化可减轻低温和低速冲击损伤

In this study, the impact response and damage mechanisms of carbon fiber reinforced polymer (CFRP) and glass fiber reinforced polymer (GFRP) hybrid face sheet sandwich composites are investigated with the aim to provide an understanding and solution to mitigate the coupling effects of low temperature and low velocity impact damage. Hybridization of face sheet is achieved by stacking CFRP and GFRP in different thickness configurations. Samples are subjected to low-velocity impact at 23 °C and −70 °C to compare and understand the effect of cold temperature in the Arctic environment. Results show that hybridization improves the impact performance at −70 °C. CFRP layers and foam core become extremely brittle at low temperature, but GFRP layers maintain a certain extent of ductility and enhanced laminate strength at low temperature. Moreover, different damage modes (delamination, fiber breakage, core crushing, core shear, face sheet debonding, back face fiber splitting) are observed and characterized by X-ray micro-computed tomography. The additions of GFRP layers to CFRP face sheet mitigated the increased brittle fiber failure observed at low temperatures, however the impact characteristics and damage size was found to be dependent on the hybridization configuration.

本研究对碳纤维增强聚合物（CFRP）和玻璃纤维增强聚合物（GFRP）混合面片夹层复合材料的冲击响应和损伤机理进行了研究，旨在为减轻低温和低速冲击损伤的耦合效应提供一种理解和解决方案。通过以不同厚度配置堆叠 CFRP 和 GFRP，实现了面片的混合。样品在 23 °C 和 -70 °C 下受到低速冲击，以比较和了解北极环境中低温的影响。结果表明，杂化提高了-70 °C时的冲击性能。CFRP 层和泡沫芯材在低温下变得极脆，但 GFRP 层在低温下保持了一定的延展性并增强了层压强度。此外，X 射线微观计算机断层扫描还观察到不同的破坏模式（分层、纤维断裂、芯材挤压、芯材剪切、面片脱粘和背面纤维分裂），并对其进行了表征。在 CFRP 面板上添加 GFRP 层可减轻低温下观察到的纤维脆性破坏的增加，但发现冲击特性和破坏大小取决于杂化配置。

Shape memory behaviors of three-dimensional five-directional braided composites with different axial yarns arrangements

Yingying Qi, Shuwei Huang, Haoxuan Zhang, Bohong Gu, Baozhong Sun, Wei Zhang

doi:10.1016/j.compstruct.2024.118105

不同轴向纱排列的三维五向编织复合材料的形状记忆行为

The effect of braided structure on shape memory behaviors of 3D braided composites is critical to design the responses of the composite under external fields. Here we report the effect of axial yarn on shape memory behaviors of three-dimensional five-directional (3D5d) braided shape memory polymer composites (SMPCs) under bending. It was found that the axial yarns will improve bending stiffness and electro-thermal behaviors significantly. The thermomechanical deformation and shape memory effect of SMPCs are influenced by the braiding structural parameters. Specifically, the 3D5d SMPCs exhibits a 53.6% increase in bending recovery force and a faster shape recovery speed than those of 3D four-directional SMPCs. We found from finite element analyses (FEA) that the axial yarns positions influence the inner stress distribution and shape memory behaviors of SMPCs. The axial yarns distributed on both sides of SMPC influence the shape memory behaviors more than those of the middle layer.

编织结构对三维编织复合材料形状记忆行为的影响对于设计复合材料在外力作用下的响应至关重要。在此，我们报告了轴向纱线对三维五向（3D5d）编织形状记忆聚合物复合材料（SMPC）在弯曲下的形状记忆行为的影响。研究发现，轴向纱线能显著改善弯曲刚度和电热行为。SMPC 的热机械变形和形状记忆效应受编织结构参数的影响。具体而言，与三维四向 SMPC 相比，三维五向 SMPC 的弯曲恢复力增加了 53.6%，形状恢复速度更快。我们通过有限元分析（FEA）发现，轴向纱线的位置会影响 SMPC 的内部应力分布和形状记忆行为。分布在 SMPC 两侧的轴向纱线比中间层的纱线对形状记忆行为的影响更大。

Composites Part A: Applied Science and Manufacturing

Improving the thermal conductivity of an epoxy composite with chemically boron nitride-grafted carbon fiber

Wonyoung Yang, Jihoon Kim, Pei-Chen Su, Jooheon Kim

doi:10.1016/j.compositesa.2024.108192

 

用化学氮化硼接枝碳纤维改善环氧树脂复合材料的导热性能

The rapid progress of electronic devices like electric vehicles, smartphones, and IoT systems has fueled the demand for compact, high-performance batteries. However, a critical challenge arises from heat accumulation within these devices, leading to malfunctions and reduced efficiency. To address this, efficient heat dissipation is crucial, with thermal interface materials (TIMs) widely used for heat transfer. While polymers are favored for TIMs due to their ease of processing and electrical insulation, their low thermal conductivity poses limitations. In this study, a solution is proposed by chemically grafting boron nitride (BN), a ceramic-based filler, onto carbon fiber (CF) surfaces. This BN-g-CF hybrid filler, formed through a reaction between acyl chlorides and amine groups, exhibits superior compatibility with polymer matrix. Characterization confirms successful treatment, and thermal conductivity measurements show a remarkable enhancement, positioning the BN-g-CF/epoxy resin composite as a promising solution for efficient thermal management in various electronic industries.

电动汽车、智能手机和物联网系统等电子设备的快速发展，刺 激了对紧凑型高性能电池的需求。然而，这些设备内部的热量积累带来了严峻的挑战，导致故障和效率降低。为解决这一问题，高效散热至关重要，热界面材料（TIM）被广泛用于热传递。虽然聚合物因其易于加工和电气绝缘性能而成为热界面材料的首选，但其较低的热传导率却带来了局限性。本研究提出了一种解决方案，即通过化学方法将氮化硼（BN）这种陶瓷基填料接枝到碳纤维（CF）表面。这种 BN-g-CF 混合填料是通过酰基氯和胺基反应形成的，与聚合物基体具有极佳的兼容性。表征结果表明处理成功，热导率测量结果表明显著提高，BN-g-CF/环氧树脂复合材料有望成为各种电子工业高效热管理的解决方案。

Multi-DORGP for fast uncertainty quantification of multi-scale irregular defects in super large-scale fiber-reinforced composite

Yunguo Cheng, Timon Rabczuk, Chensen Ding

doi:10.1016/j.compositesa.2024.108196

用于快速量化超大尺度纤维增强复合材料中多尺度不规则缺陷的 Multi-DORGP

The presence of randomly distributed irregular defects in fiber-reinforced composites significantly impacts the structural response, yet traditional machine learning schemes often require an extensive number of samples, resulting in time-consuming processes. Therefore, this paper introduces a novel approach, termed the dual order-reduced Gaussian Process emulators (Multi-DORGP), aimed at efficiently quantifying the uncertainty of multi-scale irregular defects in fiber-reinforced composites. This is achieved by accurately characterizing the multi-scale irregular defects through precise geometric representations, utilizing massive discrete nodes and fine meshes to address the limitations of parameterization methods that may overlook shape and size differences of defects. Moreover, we comprehensively quantify uncertainty across micro, meso, and macro scales, considering spatially randomly distributed locations, sizes, and irregular shapes of defects. Notably, the Multi-DORGP scheme is presented to alleviate the computational burden associated with extremely high-dimensional data (e.g., up to 23.3 million variables). In which, we decouple and build the latent spaces for raw data assisted by principal component analysis, and Gaussian Process regression is built and trained by the coefficients between the latent spaces. Through illustrative examples, including a real-life application involving an airplane wing, we validate the proposed scheme's capability to accurately quantify the uncertainty of multi-scale irregular defects in large-scale fiber-reinforced composites using significantly few samples (e.g., 100).

纤维增强复合材料中随机分布的不规则缺陷会严重影响结构响应，但传统的机器学习方案往往需要大量样本，导致过程耗时。因此，本文介绍了一种新方法，即双阶还原高斯过程仿真器（Multi-DORGP），旨在有效量化纤维增强复合材料中多尺度不规则缺陷的不确定性。为此，我们通过精确的几何表征来准确描述多尺度不规则缺陷，利用大规模离散节点和精细网格来解决参数化方法可能忽略缺陷形状和尺寸差异的局限性。此外，考虑到缺陷在空间上随机分布的位置、尺寸和不规则形状，我们全面量化了微观、中观和宏观尺度上的不确定性。值得注意的是，我们提出了多 DORGP 方案，以减轻与极高维数据（如多达 2330 万个变量）相关的计算负担。在该方案中，我们通过主成分分析对原始数据进行解耦并建立潜在空间，然后通过潜在空间之间的系数建立并训练高斯过程回归。通过示例（包括涉及飞机机翼的实际应用），我们验证了所提出方案的能力，即使用极少的样本（如 100 个）就能准确量化大规模纤维增强复合材料中多尺度不规则缺陷的不确定性。

Composites Part B: Engineering

Tailor-made Co3O4@CeO2 based nanofibrous membrane with enhanced catalytic reactivity for efficient degradation of antibiotic

Dong Wang, Siping Ding, Zhenzhen He, Tonghui Zhang, Xuefen Wang

doi:10.1016/j.compositesb.2024.111424

 

基于 Co3O4@CeO2 的定制纳米纤维膜具有更强的催化反应活性，可高效降解抗生素

In this work, a novel Co3O4@CeO2 nanofibrous membrane was prepared by the combination of interfacial defect engineering strategy and coaxial electrospinning for unusual levofloxacin degradation. Implanting active Co3O4 into CeO2 derived from Ce-UiO-66 created more oxygen vacancies and improved the interfacial interaction (electron transfer and specific surface area). In addition, accelerated redox recycling occurred on the catalyst surface because of the cooperation of Co sites and Ce sites. As a result, the optimal Co3O4@CeO2 nanocomposite showed an unexpectedly improved degradation efficiency of levofloxacin with a rate constant higher than 6.9 times (CeO2) and 2.6 times (Co3O4), superior elimination (>98%) of antibiotic (norfloxacin, tetracycline and doxycycline hydrochloride) and dyes (methylene blue, rhodamine b, methyl orange and crystal violet). Moreover, C-type hollow structure nanofibers with increased reaction area were prepared by coaxial electrospinning to support nanoparticles for consecutive wastewater treatment. The prepared nanofibrous membrane with loading 50 wt% Co3O4@CeO2 (PC50 NFMs) exhibited loose structure, resulting in 168.2 ± 12 L m−2 h−1 of permeability driven by gravity, while 164.2 L·m−2 of levofloxacin was efficiently treated. Besides, the PC50 NFMs had satisfactory reusability and stability in real water bodies. This work paved a new avenue to control water pollution through the design of membranous catalysts.

本研究结合界面缺陷工程策略和同轴电纺丝技术，制备了一种新型 Co3O4@CeO2 纳米纤维膜，用于不寻常的左氧氟沙星降解。将活性 Co3O4 植入 Ce-UiO-66 制备的 CeO2 中，可产生更多的氧空位，改善界面相互作用（电子传递和比表面积）。此外，由于 Co 位点和 Ce 位点的合作，催化剂表面的氧化还原循环加快。因此，最佳的 Co3O4@CeO2 纳米复合材料出乎意料地提高了左氧氟沙星的降解效率，其速率常数高于 6.9 倍（CeO2）和 2.6 倍（Co3O4），对抗生素（诺氟沙星、四环素和盐酸多西环素）和染料（亚甲基蓝、罗丹明 b、甲基橙和结晶紫）的消除效果也很好（大于 98%）。此外，还利用同轴电纺丝技术制备了具有更大反应面积的 C 型中空结构纳米纤维，以支持纳米颗粒连续处理废水。所制备的负载量为 50 wt% Co3O4@CeO2 的纳米纤维膜（PC50 NFMs）结构疏松，在重力作用下的渗透率为 168.2 ± 12 L m-2 h-1，可有效处理 164.2 L-m-2 的左氧氟沙星。此外，PC50 NFM 在实际水体中的重复使用性和稳定性也令人满意。这项工作为通过设计膜催化剂来控制水污染开辟了一条新途径。

Electromagnetic wave absorption of polymer derived ceramic composites tuned by multi-component oxide solid solution

Yujun Jia, Xiaopeng Wu, Bin Ren, Jiaying Ti, Yumeng Deng, Qian Wang, Hejun Li

doi:10.1016/j.compositesb.2024.111431

用多组分氧化物固溶体调节聚合物衍生陶瓷复合材料的电磁波吸收率

Polymer-derived ceramics (PDCs) are important ceramics for high temperature electromagnetic wave (EMW) absorption because of their tunable conductivity with the pyrolysis temperature. However, it is usually difficult to tune the dielectric properties of the PDCs by only controlling the content of absorption phase in the material system for the purpose of acquiring a wide EMW absorption band. In this work, we illustrate that the PDCs with wide-band high temperature absorption can be obtained through the synergistical tuning by multi-component oxide solid solution (MOS), nano ZrB2 and the metamaterial structure design. The PDCs were prepared by co-pyrolyzing the SiOC precursor, nano ZrB2 and MOS. The MOS helps to tune the permittivity of the PDCs without decreasing the conduction loss of the composites. The effective absorption band (lower than −10dB) of the metamaterial structure made by the prepared ceramic composites exceeds 12 GHz at the frequency range of 2–18 GHz from room temperature (RT) to 1000 °C, revealing a stable high temperature EMW absorption. The metamaterial structure shows good absorption in low frequency range at high temperatures, almost covering the entire S band from RT to 700 °C. The average EM absorption of the ceramic composites is lower than −15dB in the range of 2–18 GHz from RT to 1000 °C. The lowest reflection loss (RL) of the metamaterial is −45dB at 1000 °C. This study successfully address the challenge of simultaneously keeping impedance matching and retaining the strong attenuation of ceramic composites, greatly widening the high temperature EMW absorption band of PDC composites.

聚合物衍生陶瓷（PDCs）的电导率可随热解温度的变化而调整，因此是用于高温电磁波（EMW）吸收的重要陶瓷。然而，为了获得较宽的电磁波吸收带，仅通过控制材料体系中吸收相的含量通常很难调整 PDC 的介电性能。在这项工作中，我们通过多组分氧化物固溶体（MOS）、纳米 ZrB2 和超材料结构设计的协同调谐，说明了具有宽带高温吸收的 PDCs 是可以获得的。PDC 是由 SiOC 前驱体、纳米 ZrB2 和 MOS 共同热解制备的。MOS 有助于调节 PDC 的介电常数，同时不会降低复合材料的传导损耗。在室温（RT）至 1000 °C 的 2-18 GHz 频率范围内，由制备的陶瓷复合材料制成的超材料结构的有效吸收带（低于 -10dB）超过了 12 GHz，显示了稳定的高温电磁波吸收。超材料结构在高温低频范围内表现出良好的吸收性，几乎覆盖了从室温到 700 °C 的整个 S 波段。陶瓷复合材料在 2-18 GHz（从室温到 1000 °C）范围内的平均电磁吸收率低于-15dB。超材料的最低反射损耗（RL）在 1000 °C 时为 -45dB。这项研究成功地解决了同时保持阻抗匹配和陶瓷复合材料强衰减的难题，大大拓宽了 PDC 复合材料的高温电磁波吸收带。

Selective detection of norfloxacin using MIP/PEDOT modified electrode: A study on sensing performance

Yaolong Zhang, Ruxangul Jamal, Abdukeyum Abdurexit, Tursun Abdiryim, Yu Zhang, Yanqiang Zhou, Yajun Liu, Nana Fan, Zhigang Wang

doi:10.1016/j.compositesb.2024.111432

使用 MIP/PEDOT 修饰电极选择性检测诺氟沙星：传感性能研究

Developing an analytical technique for selectively detecting trace antibiotics in complex environments is essential for food safety and environmental protection. Using poly(3,4-ethylenedioxythiophene) (PEDOT) as a matrix material, we employed molecular self-assembly electropolymerization to imprint poly-o-phenylenediamine (PoPD) in the presence of norfloxacin. The study reveals that the modified GCE features a worm-like microstructure, providing a larger surface area for the construction of additional recognition sites. This modified electrode demonstrated excellent sensing performance for NOR, wide linear range (2 nmol L−1–21.11 μmol L−1), low detection limit (173 pmol L−1) (S/N = 3), and high selectivity. It effectively detected norfloxacin in different samples, yielding satisfactory results.

开发一种在复杂环境中选择性检测痕量抗生素的分析技术对于食品安全和环境保护至关重要。我们以聚（3,4-亚乙二氧基噻吩）（PEDOT）为基质材料，采用分子自组装电聚合技术，在诺氟沙星存在的情况下压印聚邻苯二胺（PoPD）。研究发现，修饰后的 GCE 具有蠕虫状的微观结构，为构建额外的识别位点提供了更大的表面积。这种改性电极对 NOR 具有优异的传感性能，线性范围宽（2 nmol L-1-21.11 μmol L-1），检测限低（173 pmol L-1）（S/N = 3），选择性高。该方法能有效检测不同样品中的诺氟沙星，结果令人满意。

Composites Science and Technology

Effect of blind-bolt repair method on vibration and compression characteristics of delaminated composite aircraft panels

Shiqing Mi, Junshan Hu, Shanyong Xuan, Jinyi Shen, Lei Xu, Wei Tian

doi:10.1016/j.compscitech.2024.110580

 

盲螺栓修复法对分层复合材料飞机面板振动和压缩特性的影响

The paper investigates the validity and reliability of the blind-bolt repair method for repairing delaminated composite aircraft panels. The delaminated specimens are prepared by inserting Teflon film during the manufacturing process to simulate interlayer damage. Subsequently, these specimens are repaired using the blind-bolt method. Modal and uniaxial compression tests are conducted to quantitatively evaluate the natural frequency, mode shape and load-bearing strength of both delaminated and bolt-repaired specimens. Digital image correlation and ultrasonic phased array techniques are employed to characterize buckling instability and damage evolution of specimens. The results reveal that the natural frequency and compressive buckling strength of delaminated specimens significantly decrease. The mode shape also changes nonlinearly with the stiffness reduction. This variation is proportional to the size and the quantity of delaminations. The blind-bolt repair method effectively restores the vibration and mechanical properties of the delaminated composite structure by reconnecting separated sub-laminates. A repair tolerance of 20 mm–60 mm is recommended for a single blind-bolt. When the delamination length is 35 mm, the repair efficiency for the critical buckling load and the ultimate load is the highest, at 58.3% and 64.4%, respectively.

本文研究了盲螺栓修复法在修复分层复合材料飞机面板方面的有效性和可靠性。分层试样是在制造过程中插入特氟龙薄膜来模拟层间损伤的。随后，使用盲孔螺栓法对这些试样进行修复。通过模态和单轴压缩试验，对分层试样和螺栓修复试样的固有频率、模态振型和承载强度进行定量评估。采用数字图像相关和超声相控阵技术来描述试样的屈曲不稳定性和损伤演变。结果表明，分层试样的固有频率和压缩屈曲强度明显降低。模态形状也随着刚度的降低而发生非线性变化。这种变化与分层的大小和数量成正比。盲螺栓修复法通过重新连接分离的子层板，有效恢复了分层复合结构的振动和机械性能。建议单个盲孔螺栓的修复公差为 20 毫米至 60 毫米。当分层长度为 35 毫米时，临界屈曲载荷和极限载荷的修复效率最高，分别为 58.3% 和 64.4%。

One-pot strategy for the preparation of nanoparticles grafted with bimodal polymers: An in-silico insight

Jinyuan Mao, Jiajia Zhou, Hong Liu

doi:10.1016/j.compscitech.2024.110583

用双峰聚合物接枝制备纳米颗粒的一锅策略：从分子内的角度看问题

Polymer nanocomposites composed of polymer-grafted nanoparticles (NPs) have garnered significant interest due to their diverse functional applications in various domains. The emerging concept of bimodal polymer brushes within the grafting-nanoparticle framework offers control over interfacial entropic and enthalpic interactions. Here, we introduce a novel one-pot strategy that integrates “grafting-to” and “grafting-from” methods to create polymer-grafted bimodal NPs. Utilizing coarse-grained molecular dynamics simulations with a stochastic reaction model, we explore the factors influencing grafting density and polydispersity in these NPs. Our findings demonstrate that this one-pot strategy achieves a polydispersity similar to the two-step “grafting-from then grafting-to” process, while attaining a moderate grafting density comparable to the “grafting-to then grafting-from” approach. Consequently, we analyze factors such as “grafting-from” reaction rates, and initial feeding ratios, step-addition techniques which collectively influence the final grafting density and polydispersity index within this one-pot strategy. This comprehensive investigation enhances our understanding of the kinetics behind synthesizing bimodal polymer-grafted NPs and offers insights for designing polymer-based nanocomposites with improved performance.

由聚合物接枝纳米粒子（NPs）组成的聚合物纳米复合材料因其在不同领域的多种功能应用而备受关注。在接枝纳米颗粒框架内的双模聚合物刷这一新兴概念提供了对界面熵和焓相互作用的控制。在这里，我们介绍了一种新颖的一锅策略，该策略将 "接枝到 "和 "接枝自 "方法整合在一起，以创建聚合物接枝的双峰 NPs。利用随机反应模型进行粗粒度分子动力学模拟，我们探索了影响这些 NPs 接枝密度和多分散性的因素。我们的研究结果表明，这种一锅策略所实现的多分散性与 "先接枝-再接枝-再接枝-再接枝 "的两步法相似，而达到的适度接枝密度与 "先接枝-再接枝-再接枝-再接枝 "的方法相当。因此，我们分析了 "从接枝到接枝 "反应速率、初始进料比、步骤添加技术等因素，这些因素共同影响了这种一锅策略的最终接枝密度和多分散指数。这项全面的研究加深了我们对合成双峰聚合物接枝 NPs 动力学的理解，并为设计性能更佳的聚合物基纳米复合材料提供了启示。