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Valentin Launay Aurore Caron Guillaume Noirbent Didier Gigmes Frédéric Dumur Jacques Lalevée 《Advanced functional materials》2021,31(7):2006324
Photoinduced thermal polymerization upon Near-InfraRed (NIR) light has been recently reported in the literature as an efficient tool for polymer synthesis. In this work, a completely different approach is developed since polymeric materials containing a very low amount of a stimuli-responsive compound are prepared by using a benchmark UV photoinitiator. As the stimuli-responsive compound, an organic dye strongly absorbing in the near-infrared region is selected. The heat released by its irradiation with an inexpensive and highly penetrating NIR light source allows the development of an unprecedented approach for reprocessing, reshaping, recycling, and self-healing. Several parameters have been studied in order to determine their influence on the polymer temperature: the wavelength of the NIR irradiation, the irradiance of the NIR light source, the choice of heater (IR-813 p-toluenesulfonate or a squaraine dye), and the heater concentration. The thermoplastics bonding and debonding has also been studied and showed promising results since two pieces of polymers could be pasted together after a short time of NIR irradiation. Finally, self-healing ability of the thermoplastic is investigated and furnished impressive results even for large scratches. 相似文献
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Chunhua An Fengmin Nie Rongjie Zhang Xinli Ma Dahao Wu Yang Sun Xiaodong Hu Dong Sun Li Pan Jing Liu 《Advanced functional materials》2021,31(22):2100136
Flexible photodetectors are fundamental elements to develop flexible/wearable systems, which can be widely used for in situ health and environmental monitoring, human–machine interacting, flexible displaying, etc. However, the degraded performance or even malfunction under severe mechanical deformation and/or damage remains a key challenge for current flexible photodetectors. In this article, a flexible photodetector is developed with strong self-healing capability and stable performance under large deformation. This photodetector is made of the 2D material self-healing film by mixing 2D materials homogenously with the self-healing polymer of imidazolium-based norbornene polymerized with ionic liquids and counterions. The 2D material self-healing films show enhanced light absorption, and thus, decent photoresponse as compared to the pure self-healing film. The achieved photoresponse remains stable and even increases under small tensile strain within 150%, while decreases slightly under large tensile strain up to 1000%. Moreover, the photodetector not only can be fully recovered from repeated mechanical cuttings, but also presents excellent long-term stability in ambient condition for 500 days without showing any obvious degraded performance. Furthermore, a large-area 2D material self-healing photodetection array is designed with adjustable pixel size, which successfully recognizes the patterns of “T”, “J”, and “U”. 相似文献
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从理论和实验两个方面研究角向偏振无衍射光束在自由空间和障碍物空间中的传输特性. 理论上模拟了角向偏振无衍射光束在自由空间以及障碍物空间传播过程中的光强分布与偏振态变化情况. 实验中利用高斯光束先通过偏振转换仪, 再入射到轴棱锥上产生角向偏振无衍射光束. 进而研究其在空间中的传输情况, 并通过分析其经过扇形障碍物后光强分布变化情况讨论障碍物对偏振态的影响和光束的自重建特性. 结果表明: 障碍物遮挡区域光强沿z轴方向逐渐恢复, 且阴影区域沿障碍物所在位置的相反方向移动; 光束的偏振态局部发生变化, 该变化与障碍物所在位置有关. 理论仿真和实验结果一致. 相似文献
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路由的自愈性是指在网络故障发生后,路由系统能够自动恢复或重建路由,保证分组转发不受影响的能力.虽然目前的域内路由协议都具备一定的自愈能力,但是它们的自愈时间通常在几秒到上百秒之间,难以完全满足用户的需求.在自愈过程中,网络路由可能是错误的,甚至会出现"路由黑洞"或"路由环路",导致分组丢失,影响网络应用.为了解决这个问题,研究者设计了很多域内自愈路由方案.本文在总结和分析了当前域内自愈路由的问题后,提出了自愈路由模型,依据模型将这些方案分成五类:调整设置权值、限制洪泛、快速重路由、多路径和本地重路由.在分析每类中典型算法的基础上,总结对比了各类方案的特点,详细分析了算法的有效性.最后探讨了域内自愈路由研究中需要进一步考虑的问题. 相似文献
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SDH自愈环网特性分析及应用 总被引:3,自引:0,他引:3
随着数据通信业务的迅猛发展,现代社会对网络的安全性要求越来越高,SDH自愈保护是提高光网络安全性的重要手段之一。通过对SDH自愈环的结构特性及环网保护机制的介绍,分析比较了4种常用SDH自愈环的优缺点,为网络安全建设提供依据。结合山西某地区网通SDH光传输网络特点介绍应用实例,最后对SDH传输网的保护技术进行展望。 相似文献
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Weiting Ma Shuang Wan Xiurui Cui Guolin Hou Ying Xiao Junfeng Rong Shimou Chen 《Advanced functional materials》2023,33(15):2212821
Lithium batteries (LBs) are developed tremendously owing to their excellent energy density as well as cyclic persistence, exhibiting promising applications from portable devices to e-transportation and grid fields. However, with the ever-increasing demand for intelligent wearable electronics, more requests are focused on high safety, good durability, and satisfied reliability of LBs. The self-healing route, which can simulate the ability of organic organisms to repair damage and recover initial function through its intrinsic vitality, is believed to be an efficient strategy to alleviate the unavoidable physical or chemical fatigue and damage issues of LBs, beneficial for the realization of the above mentioned high requests. In this review, the applicability and development of self-healing materials are summarized in electrodes, electrolytes, and interfacial layers in recent years, focusing on exploring the feasibility of different self-healing strategies in LBs, discussing the advantages and disadvantages of existing strategies in different parts of batteries, and indicating the possible research directions for beginners who are interested in this field. Finally, the critical challenges and the future research directions as well as opportunities are prospected. 相似文献