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【新文速递】2024年2月26日复合材料SCI期刊最新文章

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

Composite Structures

A modified equally-spaced method (MEQS) for fibre placement in additive manufacturing of topology-optimised continuous carbon fibre-reinforced polymer composite structures

Shuai Wang, Haoqi Zhang, Aonan Li, Junaid Ahmad Abdul Qayyum, Yongxing Wang, Zhelong He, Jie Liu, Dongmin Yang

doi:10.1016/j.compstruct.2024.117998

拓扑优化连续碳纤维增强聚合物复合材料结构增材制造中纤维铺放的改良等距法 (MEQS)

This study proposes a modified equally-spaced (MEQS) method for the path design of continuous fibres in additive manufacturing (AM) of topologically optimised composite structures. The MEQS method addresses the low fibre infill rate issue of the traditional Equally-Spaced (EQS) method by utilising the Offset method to generate looped printing paths around the internal cavities and gaps between continuous fibre paths. The developed MEQS method was first illustrated against EQS and Offset methods using an open-hole composite plate in which topology and material orientation were simultaneously optimised using the discrete–continuous parameterisation (DCP) method. Actual printing path-based finite element modelling showed that the MEQS method achieves a 25.32% increase in stiffness compared to the Offset method. Experimental testing of the additively manufactured open-hole composite plates showed that the MEQS method improves the stiffness and strength by 15.52% and 27.38%, respectively, compared to the Offset method. The proposed MEQS was further demonstrated through two other case studies by finite element modelling, showing that the stiffness of MEQS has increased by an average of 66.71% and 14.95% compared to EQS and Offset, respectively.

本研究提出了一种改进的等间距(MEQS)方法,用于拓扑优化复合材料结构的增材制造(AM)中连续纤维的路径设计。MEQS 方法利用 "偏移 "方法在内部空腔和连续纤维路径之间的间隙周围生成循环打印路径,从而解决了传统等间距 (EQS) 方法中纤维填充率低的问题。开发的 MEQS 方法首先使用开孔复合板与 EQS 和偏移法进行了对比,其中拓扑结构和材料取向同时使用离散连续参数化 (DCP) 方法进行了优化。基于实际印刷路径的有限元建模显示,与偏移法相比,MEQS 法的刚度提高了 25.32%。对添加制造的开孔复合板进行的实验测试表明,与偏移法相比,MEQS 法的刚度和强度分别提高了 15.52% 和 27.38%。通过有限元建模进行的另外两个案例研究进一步证明了所提出的 MEQS,结果表明,与 EQS 和偏移法相比,MEQS 的刚度平均分别提高了 66.71% 和 14.95%。


Composites Part A: Applied Science and Manufacturing

Damage failure analysis of flexible-oriented three dimensional woven composites with void defects: An experimental and numerical study

Hao Huang, Zhongde Shan, Jianhua Liu, Zitong Guo, Zheng Sun, Dong Wang, Chenchen Tan, Juncheng Luo

doi:10.1016/j.compositesa.2024.108106

具有空隙缺陷的柔性导向三维编织复合材料的损伤失效分析:实验和数值研究

Three-dimensional woven structures have garnered significant interest due to their enhanced mechanical properties and structural integrity. This study delves into a detailed analysis of progressive damage failure in multi-structured, flexible-oriented three-dimensional woven composites (FO3DWC), with a specific focus on the effects of voids. Employing the flexible-oriented three-dimensional woven process (FO3DWP), four distinct structures were fabricated and subjected to uniaxial tensile tests. The study integrates an progressive damage failure model coupled with a random element selection method to investigate the effects of void defects on mechanical properties. The results show that significant variations occur in the strength of the L45135 structure due to the void defects, with a maximum decrease of up to 4.37% when the porosity is 5%. This research provides a quantitative understanding of how voids impact the mechanical performance of FO3DWC, offering valuable guidance for material design and application in various engineering fields.

三维编织结构因其更高的机械性能和结构完整性而备受关注。本研究详细分析了多结构柔性导向三维编织复合材料(FO3DWC)的渐进破坏失效,重点关注空隙的影响。采用柔性导向三维编织工艺(FO3DWP)制造了四种不同的结构,并对其进行了单轴拉伸试验。该研究将渐进式损伤失效模型与随机元素选择方法相结合,研究了空隙缺陷对机械性能的影响。结果表明,由于空隙缺陷,L45135 结构的强度发生了显著变化,当孔隙率为 5%时,强度最大下降达 4.37%。这项研究提供了对空隙如何影响 FO3DWC 机械性能的定量理解,为各种工程领域的材料设计和应用提供了宝贵的指导。


Composites Part B: Engineering

A comprehensive review of hydrogen-induced swelling in rubber composites

Chilou Zhou, Xianhui Liu, Yiran Zheng, Zhengli Hua

doi:10.1016/j.compositesb.2024.111342

 

橡胶复合材料中氢诱导溶胀的综合评述

Rubber sealing components are crucial and highly vulnerable parts in high-pressure hydrogen systems, which represent the weakest link where seal failure becomes the crucial factor limiting the increase in working pressure of hydrogen energy equipment. Prolonged exposure to hydrogen environments causes rubber materials to experience volumetric expansion, resulting in decreased sealing reliability and durability, posing significant safety risks. This review focuses on rubber sealing materials used in hydrogen energy equipment. Firstly, the current mainstream mechanisms of hydrogen-induced swelling are introduced, covering the hydrogen exposure and decompression stages. Subsequently, the impact of hydrogen-induced swelling on the micromorphology damage, mechanical performance deterioration and sealing performance reduction of rubber is elucidated. Furthermore, the primary influencing factors of rubber hydrogen-induced swelling are explored and summarized. Based on the analysis of the current state of researches, several recommendations are proposed for the study of hydrogen-induced swelling of rubber sealing materials, including broadening the influencing factors and constructing the correlations between hydrogen-induced swelling and other damages such as frictional wear to contributing the safe application of rubber seal in high-pressure hydrogen systems.

在高压氢气系统中,橡胶密封部件是非常脆弱的关键部件,是最薄弱的环节,密封失效成为限制氢能设备工作压力提高的关键因素。长期暴露在氢气环境中会导致橡胶材料发生体积膨胀,从而降低密封可靠性和耐用性,带来重大安全风险。本综述侧重于氢能设备中使用的橡胶密封材料。首先,介绍当前氢气诱导膨胀的主流机制,包括氢气暴露阶段和减压阶段。随后,阐明了氢致膨胀对橡胶微观形貌损伤、机械性能恶化和密封性能降低的影响。此外,还探讨并总结了橡胶氢致溶胀的主要影响因素。在分析研究现状的基础上,对橡胶密封材料的氢致溶胀研究提出了若干建议,包括拓宽影响因素,构建氢致溶胀与摩擦磨损等其他损伤之间的相关性,以促进橡胶密封在高压氢气系统中的安全应用。


Fabrication of hollow Ni/NiO/C/MnO2@polypyrrole core-shell structures for high-performance electromagnetic wave absorption

Shixuan Feng, Haowen Wang, Jian Ma, Zhongtai Lin, Chuanjin Wang, Xue Li, Mingliang Ma, Tingxi Li, Yong Ma

doi:10.1016/j.compositesb.2024.111344

 

制备用于高性能电磁波吸收的中空 Ni/NiO/C/MnO2@polypyrrole 核壳结构

In response to the increasingly serious problem of electromagnetic wave pollution, there is a growing demand for materials capable of absorbing electromagnetic waves. A crucial strategy involves optimizing the microstructure and composition of these materials. In this study, the Ni/NiO/C/MnO2@PPy (NCMP) composites are successfully fabricated through the combination of hydrothermal method, high-temperature calcination process, chemical method and in situ polymerization. Due to the strong synergistic effect of the dielectric and magnetic components, and good impedance match, the NCMP-40 exhibits excellent electromagnetic wave absorption properties, with an optimal reflection loss (RLmin) of −56.23 dB at a thickness of 3.87 mm, and a high effective absorption bandwidth (EAB) of 6.86 GHz (10.68–17.54 GHz) at a thickness of 1.97 mm covering the entire Ku-band part of the X-band. Moreover, the radar cross section (RCS) attenuation is obtained through a simulation procedure. Compared to the sole perfect electrically conductive (PEC) layer, the PEC layer coated with NCMP-40 achieves an RCS value consistently below −10 dB m2 in the range of −60° < θ < 60°, and an RCS value is −22.0 dB m2 at θ = 0°. The prepared NCMP-40 presented herein shows excellent electromagnetic wave absorption performances. And this study provides a new method for the structural design of electromagnetic wave absorption materials.

为了应对日益严重的电磁波污染问题,人们对能够吸收电磁波的材料的需求与日俱增。其中一项重要策略就是优化这些材料的微观结构和成分。本研究结合水热法、高温煅烧法、化学法和原位聚合法,成功制备了 Ni/NiO/C/MnO2@PPy (NCMP)复合材料。由于介电成分和磁性成分的强协同效应以及良好的阻抗匹配,NCMP-40 表现出优异的电磁波吸收特性,在厚度为 3.87 毫米时的最佳反射损耗(RLmin)为 -56.23 dB,在厚度为 1.97 毫米时的有效吸收带宽(EAB)为 6.86 GHz(10.68-17.54 GHz),覆盖了整个 Ku 波段的 X 波段部分。此外,还通过模拟程序获得了雷达截面(RCS)衰减。与唯一的完美导电 (PEC) 层相比,涂有 NCMP-40 的 PEC 层在 -60° < θ < 60° 范围内的 RCS 值始终低于 -10 dB m2,在 θ = 0° 时的 RCS 值为 -22.0 dB m2。本文介绍的制备的 NCMP-40 具有优异的电磁波吸收性能。这项研究为电磁波吸收材料的结构设计提供了一种新方法。


Composites Science and Technology

Impact behaviour of bio-inspired sandwich panels integrally manufactured from 3D printed continuous carbon fibre reinforced polyamide

I. Sukia, A. Esnaola, B. Erice, J. Aurrekoetxea

doi:10.1016/j.compscitech.2024.110515

 

用 3D 打印连续碳纤维增强聚酰胺整体制造的生物启发夹层板的冲击性能

This paper studies the effect of several design parameters on the impact performance of fully 3D printed sandwich panels with a core cell unit inspired by the trabecular structure of the forewing of a beetle. The key finding is that the asymmetric sandwich panel, which featured a thicker face sheet at the back and a core with a variating cell wall thickness of weak-to-strong, exhibited the highest impact energy dissipation. Specifically, 98.1 J was dissipated with 6970 N of peak load. This surpassed the performance of the sandwich panel with homogeneous cell wall thickness and asymmetric face sheets, which dissipated only 72.1 J and failed at 5406 N. In general, asymmetric configurations were found to dissipate greater energy than symmetric face sheets, and for sandwich plates with homogenous cores, the configuration with the thickest back face sheet proved more resistant to damage than the opposite asymmetric configuration.

本文研究了几个设计参数对全三维打印夹层板冲击性能的影响,夹层板的核心单元灵感来自甲虫前翅的小梁结构。研究的主要发现是,非对称夹层板(背面面层较厚,核心单元壁厚由弱到强不断变化)的冲击能量耗散最高。具体来说,6970 牛顿的峰值载荷可耗散 98.1 焦耳的能量。总体而言,非对称结构比对称结构能耗散更大的能量,而对于具有同质芯材的夹芯板来说,具有最厚背面面板的结构比相反的非对称结构更能抵抗破坏。


The chemistry, properties and performance of flame-retardant rubber composites: Collecting, analyzing, categorizing, machine learning modeling, and visualizing

Paulina Wiśniewska, Elnaz Movahedifar, Krzysztof Formela, M.Z. Naser, Henri Vahabi, Mohammad Reza Saeb

doi:10.1016/j.compscitech.2024.110517

 

阻燃橡胶复合材料的化学性质、特性和性能:收集、分析、分类、机器学习建模和可视化

Rubbers combine the flexibility with mechanical strength, supporting myriad applications, but suffer from inherent flammability. Development of flame-retardant rubber composites (FRRCs) has intensively practiced over years, but not comprehensively reviewed, which outlined collecting, analyzing, screening, classifying, and interpreting the literature aimed at classification of FRRCs. Herein, we quantify and visualize flame retardancy of natural and synthetic FRRCs by grouping FRRCs based on flame retardants (FRs) used among green, mineral, phosphorus-based, nitrogen-based, carbonaceous, and hybrids of two or more types. Available data on cone calorimetry, limited oxygen index (LOI), and UL-94 of FRRCs were carefully extracted and plotted. Flame Retardancy Index (FRI) specified the Poor, Good, or Excellent classes of flame retardancy in association with the chemistry and amount of FRs to broaden future innovation avenues. Machine Learning (ML) modeling further enabled to visualize flame retardancy landscapes of natural and synthetic rubbers per FRs chemistry and amount. Moreover, a downward trend in mechanical properties of FRRCS versus FR content and type was explored. Overall, this study proposed a general guideline for recognizing gaps in previous investigations and mechanics interpretations. In conclusion, the future FRRCs should take advantage of hybridizing FRs to meet fire safety requirements inspired by the innovative colorful checkered flame retardancy chart presented in this survey.

橡胶兼具柔韧性和机械强度,可支持多种应用,但也存在固有的易燃性问题。多年来,阻燃橡胶复合材料(FRRCs)的开发得到了深入实践,但并未得到全面回顾,其中包括收集、分析、筛选、分类和解释旨在对 FRRCs 进行分类的文献。在此,我们根据绿色、矿物、磷基、氮基、碳基以及两种或两种以上类型的混合物所使用的阻燃剂(FRs),对天然和合成 FRRCs 的阻燃性能进行了量化和可视化分组。我们仔细提取并绘制了有关 FRRC 的锥形量热仪、限氧指数(LOI)和 UL-94 的现有数据。阻燃指数(FRI)与阻燃剂的化学性质和数量相关联,规定了阻燃性的差、好或优等级,以拓宽未来的创新途径。通过机器学习(ML)建模,还可以根据阻燃剂的化学性质和用量直观地了解天然橡胶和合成橡胶的阻燃性。此外,还探讨了 FRRCS 机械性能随 FR 含量和类型的下降趋势。总之,本研究提出了一个总体指导原则,用于识别以往研究和力学解释中的不足之处。总之,未来的 FRRC 应利用混合 FR 的优势,以满足本次调查中提出的创新彩色方格阻燃图所激发的防火安全要求。


Bionic hierarchical metalized thermally responsive dynamic daytime passive radiative cooling nanocomposites

Junbao Yan, Mingyue Han, Liangbo Zhu, Xinyu Zhang, Mei Xu, Mengting She, Yuhan Cai, Xueyang Liu, Hua Wang, Siwei Xiong, Luoxin Wang

doi:10.1016/j.compscitech.2024.110518

 

仿生分层金属化热响应动态日间被动辐射冷却纳米复合材料

Passive heat management technology holds significant promise in mitigating the fossil energy crisis. However, most current passive radiative cooling textiles merely reflect sunlight, causing unnecessary cooling in cold regions during winter and lacking dynamic control. Herein, we were inspired by chameleons to develop a temperature-sensitive passive heat management nanocomposite using a multi-layered assembly strategy. This nanocomposite consisted of the core layer of metal-coated fabric and the surface layer composed of polydimethylsiloxane (PDMS), hexagonal boron nitride (h-BN), and organic temperature-variable material (OTM). When the nanocomposite contained 15 wt% OTM, the average reflectance in the cold (15 °C) and hot (30 °C) modes was 47.66% and 80.92%, respectively. Additionally, the average emissivity was found to be 91.64% and 91.31% in the cold and hot modes, respectively. Significantly, the nanocomposite demonstrated cyclic stability in multiple temperature response tests. In practical experiments, it effectively reduced the temperature within a car and a small wooden house model by 14.0 and 7.1 °C, respectively. Moreover, the nanocomposite facilitated the accelerated ice melting at a rate of 10.85 ± 0.3 g within 1 h. Additionally, the presence of a copper metal layer in the 15 wt% OTM nanocomposite was found to contribute to antimicrobial efficiencies of 56% and 38% against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), respectively. This nanocomposite possesses the potential to stimulate inventive designs in the forthcoming era of functional nanocomposites, owing to its dynamic radiative cooling, solar heating capabilities, and scalability.

被动式热管理技术在缓解化石能源危机方面大有可为。然而,目前大多数被动辐射降温纺织品只是反射太阳光,在冬季寒冷地区会造成不必要的降温,而且缺乏动态控制。在此,我们受到变色龙的启发,利用多层组装策略开发出一种温度敏感型被动热管理纳米复合材料。这种纳米复合材料的核心层是金属涂层织物,表层由聚二甲基硅氧烷(PDMS)、六方氮化硼(h-BN)和有机变温材料(OTM)组成。当纳米复合材料含有 15 wt% 的 OTM 时,在冷(15 °C)和热(30 °C)模式下的平均反射率分别为 47.66% 和 80.92%。此外,冷模式和热模式下的平均发射率分别为 91.64% 和 91.31%。值得注意的是,纳米复合材料在多重温度响应测试中表现出了周期稳定性。在实际实验中,它能有效地将汽车和小木屋模型内的温度分别降低 14.0 ℃ 和 7.1 ℃。此外,该纳米复合材料还能在 1 小时内以 10.85 ± 0.3 g 的速率促进冰的加速融化。此外,15 wt% OTM 纳米复合材料中的金属铜层对大肠杆菌(E. coli)和金黄色葡萄球菌(S. aureus)的抗菌效率分别为 56% 和 38%。这种纳米复合材料具有动态辐射冷却、太阳能加热功能和可扩展性,有望在即将到来的功能纳米复合材料时代激发创新设计。



来源:复合材料力学仿真Composites FEM
ACTMechanicalAdditiveSystemInspire复合材料化学拓扑优化汽车增材材料太阳能仿生控制试验纺织
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首次发布时间:2024-11-06
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【新文速递】2024年2月13日复合材料SCI期刊最新文章

今日更新:Composites Science and Technology 2 篇Composites Science and TechnologyElectrostatically self-assembled three-dimensional conductive network for highly sensitive and reliable skin-like strain sensorShengkai Li, Jian Tang, Yudong Liu, Jing Hua, Jinhui Liudoi:10.1016/j.compscitech.2024.110493 静电自组装三维导电网络,用于制造高灵敏度、高可靠性的类肤应变传感器In recent years, flexible strain sensors have garnered significant attention in industrial manufacturing and daily life. Sensitivity and reliability are two crucial characteristics of flexible strain sensors in practical applications, and they depend on the development of the sensor&#39;s internal conductive network. However, the aggregation phenomenon of conductive fillers in the elastic matrix has a serious impact on the construction of a developed conductive network. In this work, we have designed electropositive amino-functionalized carbon nanotubes (CNTs-p) based on the electrostatic self-assembly of electronegative MXene in the aqueous phase. Compared to the use of surfactants, the electrical modulation of carbon nanotubes through chemical bonding modification is more robust and the electrostatic self-assembly with MXene is more stable. CNTs-p and MXene were self-assembled by electrostatic attraction in butyl latex and uniformly dispersed in the latex. Following demulsification, the polymer composite film (MXene&amp;CNTs-p/IIR) with a three-dimensional conductive network was obtained. The skin-like strain sensor, which utilizes the conductive composite film, demonstrates high sensitivity (gauge factor (GF) = 35137 that is among the highest values for the reported strain sensor), remarkable reliability (The signal monitoring capability remains after 15000 cycles), and excellent responsiveness (62 ms). Additionally, the skin-like strain sensor boasts a wide detection range (0–431%) and unprecedented stability, enabling strain sensing functionality in a wide temperature range of -10—100 °C, as well as strong acid (pH = 1) and strong alkali (pH = 11) environment. The preparation of MXene&amp;CNTs-p/IIR provides a safe, environmentally friendly and effective method for improving the sensitivity and reliability of flexible sensors in wearable intelligent electronics and health detection.近年来,柔性应变传感器在工业制造和日常生活中备受关注。灵敏度和可靠性是柔性应变传感器在实际应用中的两个关键特性,而这两个特性取决于传感器内部导电网络的发展。然而,导电填料在弹性基体中的聚集现象严重影响了导电网络的构建。在这项工作中,我们基于电负性 MXene 在水相中的静电自组装,设计出了电正性氨基功能化碳纳米管(CNTs-p)。与使用表面活性剂相比,通过化学键修饰对碳纳米管进行电学调制的效果更强,与 MXene 的静电自组装也更稳定。CNTs-p 和 MXene 通过静电吸引在丁基胶乳中自组装,并均匀地分散在胶乳中。破乳后,得到了具有三维导电网络的聚合物复合薄膜(MXene&amp;CNTs-p/IIR)。利用该导电复合薄膜制成的类肤应变传感器具有高灵敏度(测量系数 (GF) = 35137,是目前已报道的应变传感器中最高值之一)、卓越的可靠性(15000 次循环后仍能保持信号监测能力)和出色的响应速度(62 毫秒)。此外,这种类似皮肤的应变传感器还具有很宽的检测范围(0-431%)和前所未有的稳定性,可在 -10-100 °C 的宽温度范围以及强酸(pH = 1)和强碱(pH = 11)环境中实现应变传感功能。MXene&amp;CNTs-p/IIR 的制备为提高可穿戴智能电子产品和健康检测领域柔性传感器的灵敏度和可靠性提供了一种安全、环保和有效的方法。Construction of micro-nano hybrid structure based on carbon nanotube whisker and alumina for thermally conductive yet electrically insulating silicone rubber compositesXiaowang Ji, Zhaoyu Lu, Junyan Wang, Neng Ye, Huan Zhang, Letian Zhou, Jingchao Li, Yonglai Ludoi:10.1016/j.compscitech.2024.110495 构建基于碳纳米管晶须和氧化铝的微纳混合结构,用于导热和绝缘硅橡胶复合材料High-performance electronics urgently need more effective thermally conductive rubber composites to solve interfacial heat transfer problems in the thermal management systems. Tiny amounts nanocarbon materials (NCM) can significantly improve the thermal conductivity of conventional ceramic-filled rubber composites, but the volume exclusion effect of micrometer ceramic fillers makes NCM highly susceptible to the formation of the conductive pathways, which inevitably leads to the substantial decrease in the volume resistivity of the materials, posing a safety hazard, such as short circuits, to electronic devices. Here, we report an electrostatic self-assembly method to prepare CNW@n-Al2O3 hybrids by loading nano-alumina (n-Al2O3) onto carbon nanotube whiskers (CNW) and co-filling them with micrometer alumina (m-Al2O3) to silicone rubber, constructing a micro-nano-multi-level hybrid network structure, which can fully utilize the high thermal conductivity while shielding the electrical conductivity of CNW. The resulting composite filled with 2 phr of CNW@n-Al2O3 exhibits a significantly enhanced thermal conductivity of 1.137 W/(m·K) and a high volume resistance of 1.323 × 109 Ω cm, and is proved to be used as an excellent thermal interface material to assist the heat dissipation of the microelectronic chip. This study provides a facile and effective strategy for the design of thermally conductive yet electrically insulating rubber composites filled with CNW, which shows a bright application prospect in the thermal management of high-performance electronic devices.高性能电子产品迫切需要更有效的导热橡胶复合材料来解决热管理系统中的界面传热问题。微量纳米碳材料(NCM)可显著提高传统陶瓷填充橡胶复合材料的导热性能,但微米级陶瓷填料的体积排斥效应使 NCM 极易形成导电通路,从而不可避免地导致材料的体积电阻率大幅下降,给电子设备带来短路等安全隐患。在此,我们报告了一种制备 CNW@n-Al2O3 混合材料的静电自组装方法,即在碳纳米管晶须(CNW)上负载纳米氧化铝(n-Al2O3),并在硅橡胶中共同填充微米氧化铝(m-Al2O3),构建微纳多层次混合网络结构,从而在屏蔽 CNW 导电性的同时充分利用其高热传导性。填充了 2 phr 的 CNW@n-Al2O3 的复合材料的热导率显著提高,达到 1.137 W/(m-K),体积电阻高达 1.323 × 109 Ω cm,可用作优良的热界面材料,帮助微电子芯片散热。该研究为设计填充了氯化萘的导热绝缘橡胶复合材料提供了一种简便有效的策略,在高性能电子设备的热管理方面具有广阔的应用前景。来源:复合材料力学仿真Composites FEM

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