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891.
892.
针对离散型制造车间电子装备生产调测线中存在的多品种批量测试压力大的问题,结合制造物联技术的应用重新定义当前测试过程,设计具有实时测试信息特征的工作模式和通信手段,以适应车间数字化改造升级的要求。以离散车间自动测试系统为研究对象,通过搭建面向实时测试过程的工业物联识别环境,构建自动测试系统信息化体系框架,详细分析了基于开关切换和自动化流水线的多被测件测试技术、现场设备在线互操作协同技术、基于实时跟踪的数据通信技术等关键技术,给出了基于浏览器/服务器结构的网络化柔性测试生产线实现方法,为提升制造车间的整体测试服务水平提供了基础。 相似文献
893.
Perovskite solar cell has emerged as a promising candidate in flexible electronics due to its high mechanical flexibil-ity,excellent optoelectronic properties,light weight and low cost.With the rapid development of the device structure and mater-ials processing,the flexible perovskite solar cells (FPSCs) deliver 21.1% power conversion efficiency.This review introduces the latest developments in the efficiency and stability of FPSCs,including flexible substrates,carrier transport layers,perovskite films and electrodes.Some suggestions on how to further improve the efficiency,environmental and mechanical stability of FPSCs are provided.Specifically,we considered that to elevate the performance of FPSCs,it is crucial to substantially improve film quality of each functional layer,develop more boost encapsulation approach and explore flexible transparent electrodes with high conductivity,transmittance,low cost and expandable processability. 相似文献
894.
895.
Yang Jiang Kai Dong Xin Li Jie An Dequan Wu Xiao Peng Jia Yi Chuan Ning Renwei Cheng Pengtao Yu Zhong Lin Wang 《Advanced functional materials》2021,31(1):2005584
Accompanying the boom in multifunctional wearable electronics, flexible, sustainable, and wearable power sources are facing great challenges. Here, a stretchable, washable, and ultrathin skin-inspired triboelectric nanogenerator (SI-TENG) to harvest human motion energy and act as a highly sensitive self-powered haptic sensor is reported. With the optimized material selections and structure design, the SI-TENG is bestowed with some merits, such as stretchability ( ≈ 800%), ultrathin ( ≈ 89 µ m), and light-weight ( ≈ 0.23 g), which conformally attach on human skin without disturbing its contact. A stretchable composite electrode, which is formed by homogenously intertwining silver nanowires (AgNWs) with thermoplastic polyurethane (TPU) nanofiber networks, is fabricated through synchronous electrospinning of TPU and electrospraying of AgNWs. Based on the triboelectrification effect, the open-circuit voltage, short-circuit current, and power density of the SI-TENG with a contact area of 2 × 2 cm2 and an applied force of 8 N can reach 95 V, 0.3 µ A, and 6 mW m−2, respectively. By integrating the signal-processing circuits, the SI-TENG with excellent energy harvesting and self-powered sensing capability is demonstrated as a haptic sensor array to detect human actions. The SI-TENG exhibits extensive applications in the fields of human–machine interface and security systems. 相似文献
896.
Gwangmin Bae Gwang-Mun Choi Changui Ahn Sang-Min Kim Wonsik Kim Youngjun Choi Dawon Park Dongchan Jang Jung-Wuk Hong Seung Min Han Byeong-Soo Bae Seokwoo Jeon 《Advanced functional materials》2021,31(18):2010254
Emerging flexible optoelectronics requires a new type of protective material that is not only hard but also flexible. Organic–inorganic (O–I) hybrid materials have been used as a flexible cover window to increase wear resistance and polymer-like flexibility. However, the hardness of O–I hybrid materials is much lower than that of metals and ceramics due to the low intrinsic hardness of the organic matrix and limited volume fraction of inorganic reinforcement. Herein, a new type of hybrid nanocomposite combining an O–I hybrid material with continuous and ordered 3D inorganic nanoshell as an additional reinforcement is proposed. The 3D alumina nanoshell uniformly embedded in the epoxy-siloxane molecular hybrid (ESMH) enables a rule of mixture without a loss in flexibility. Two types of reinforcements comprising siloxane molecules and 3D alumina shell ensure a metal-like hardness (1.3 GPa), which is significantly higher than that of the typical polymers and polymer nanocomposites. The 3D hybrid nanocomposite films show superb impact resistance due to the 3D alumina nanoshell that effectively suppresses crack propagation. Inch-scale 3D hybrid nanocomposite films also endure 20 000 bending cycles without failure and maintain high transparency (>82.0% at 550 nm) in the visible regions. 相似文献
897.
Gang Xu Yanli Lu Chen Cheng Xin Li Jie Xu Zhaoyang Liu Jinglong Liu Guang Liu Zhenghan Shi Zetao Chen Fenni Zhang Yixuan Jia Danfeng Xu Wei Yuan Zheng Cui Sze Shin Low Qingjun Liu 《Advanced functional materials》2021,31(26):2100852
Real-time monitoring wound status and providing timely therapies with smart wound dressing is a promising way to treat wound infections and accelerate the healing process. Herein, to establish a closed-loop monitoring and treatment system, a fully integrated, battery-free, and wireless smart wound dressing for wound infection detection and on-demand drug delivery is developed using flexible electronics. The smart wound dressing integrated with the near field communication module can realize wireless power harvest and data transmission, on-site signal processing, and drug delivery control, through the miniaturized circuit and smartphone. The temperature, pH, and uric acid of the wound is detected simultaneously by the developed sensors to assess wound conditions. Meanwhile, the drug delivery electrode in the dressing is used to provide on-demand infection treatment by the electrically controlled antibiotics delivery. Through in vitro antibacterial experiments and in situ animal studies, it is shown that the dressing can effectively inhibit bacterial growth and accelerate wound healing, which fully validates its effectiveness in the wound treatment. Utilizing the advantages of near-field communication and flexible electronics, the battery-free and integrated design of sensing and treatment provides a promising solution for the development of a closed-loop biomedical system integrating monitoring, diagnosis, and therapy. 相似文献
898.
Gang Ge Qian Wang Yi-Zhou Zhang Husam N. Alshareef Xiaochen Dong 《Advanced functional materials》2021,31(52):2107437
In the booming development of flexible electronics represented by electronic skins, soft robots, and human–machine interfaces, 3D printing of hydrogels, an approach used by the biofabrication community, is drawing attention from researchers working on hydrogel-based stretchable ionotronic devices. Such devices can greatly benefit from the excellent patterning capability of 3D printing in three dimensions, as well as the free design complexity and easy upscale potential. Compared to the advanced stage of 3D bioprinting, 3D printing of hydrogel ionotronic devices is in its infancy due to the difficulty in balancing printability, ionic conductivity, shape fidelity, stretchability, and other functionalities. In this review, a guideline is provided on how to utilize the power of 3D printing in building high-performance hydrogel-based stretchable ionotronic devices mainly from a materials’ point of view, highlighting the systematic approach to balancing the printability, printing quality, and performance of printed devices. Various 3D printing methods for hydrogels are introduced, and then the ink design principles, balancing printing quality, printed functions, such as elastic conductivity, self-healing ability, and device (e.g., flexible sensors, shape-morphing actuators, soft robots, electroluminescent devices, and electrochemical biosensors) performances are discussed. In conclusion, perspectives on the future directions of this exciting field are presented. 相似文献
899.
Xiongxin Luo Laipan Zhu Yi-Chi Wang Jiayu Li Jiajia Nie Zhong Lin Wang 《Advanced functional materials》2021,31(38):2104928
Triboelectric nanogenerators (TENGs) represent an emerging technology in energy harvesting, medical treatment, and information technology. Flexible, portable, and self-powered electronic devices based on TENGs are much desired, whereas the complex preparation processes and high cost of traditional flexible electrodes hinder their practical applications. Here, an MXene/polyvinyl alcohol (PVA) hydrogel TENG (MH-TENG) is presented with simple fabrication, high output performance, and versatile applications. The doping of MXene nanosheets promotes the crosslinking of the PVA hydrogel and improves the stretchability of the composite hydrogel. The MXene nanosheets also form microchannels on surfaces, which not only enhances the conductivity of the hydrogel by improving the transport of ions but also generates an extra triboelectric output via a streaming vibration potential mechanism. The measured open-circuit voltage of the MH-TENG reaches up to 230 V even in a single-electrode mode. The MH-TENG can be stretched up to 200% of the original length and demonstrates a monotonical increasing relationship between the stretchable length and the short-circuit voltage. By utilizing the MH-TENG's outstanding stretchable property and ultrahigh sensitivity to mechanical stimuli, applications in wearable movement monitoring, high-precision written stroke recognition, and low-frequency mechanical energy harvesting are demonstrated. 相似文献
900.
快速反射镜(FSM) 凭借其高精度、高带宽、高分辨率等优点,已经成为激光通信中捕获、瞄准和跟踪(APT)系统的关键组成部分。本文介绍了国内外研究机构所研制多种类型FSM。首先介绍国内外FSM的发展历程和研究重点,然后,对FSM的支撑类型、驱动类型和各种位置检测元件的选择及设计进行了讨论,得到不同的支撑结构、驱动类型和位置检测元件对FSM各性能指标的影响趋势。最后,通过对各种类型FSM进行归纳总结,提出了激光通信APT系统中FSM向大行程、高精度和高带宽等方向的发展趋势。 相似文献