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961.
Zhiyuan Gao Xiao Xiao Aiden Di Carlo Junyi Yin Yanxin Wang Linjun Huang Jianguo Tang Jun Chen 《Advanced functional materials》2023,33(18):2214265
Wearable strain sensors with the ability of detecting physiological activities play an important role in personalized healthcare. Electrospun fibers have become a popular building block for wearable strain sensors due to their excellent mechanical properties, breathability, and light weight. In this review, the structure and preparation process of electrospun fibers and the conductive layer are systematically introduced. The impact of materials and structures of electrospun fibers on the wearable strain sensors with a following discussion of sensing performance optimization strategies is outlined. Furthermore, the applications of electrospun fiber-based wearable strain sensors in biomonitoring, motion detection, and human-machine interaction are presented. Finally, the challenges and promising future directions for the community of wearable strain sensors based on electrospun fibers are pointed out. 相似文献
962.
Meng Xia Dong Cai Jianbo Feng Peng Zhao Jiakai Li Rongxin Lv Guiqiu Li Lulu Yan Wei Huang Yongpeng Li Zhuyin Sui Meng Li Hui Wu Yijun Shen Juanxiu Xiao Dong Wang Qi Chen 《Advanced functional materials》2023,33(26):2214813
Sorption-based atmospheric water generation (SAWG) is a promising strategy to alleviate the drinkable water scarcity of arid regions. However, the high-water production efficiency remains challenging due to the sluggish sorption/desorption kinetics. Herein, a composite sorbent@biomimetic fibrous membrane (PPy-COF@Trilayer-LiCl) is reported by mimicking nature's Murray networks, which exhibits outstanding water uptake performance of 0.77–2.56 g g−1 at a wide range of relative humidity of 30%–80% within 50 min and fast water release capacity of over 95% adsorbed water that can be released within 10 min under one sun irradiation. The superior sorption–desorption kinetics of PPy-COF@Trilayer-LiCl are enabled by the novel hierarchically porous structure, which is also the critical factor to lead a directional rapid water transport and vapor diffusion. Moreover, as a proof-of-concept demonstration, a wearable SAWG device is established, which can operate 10 sorption–desorption cycles per day in the outdoor condition and produce a high yield of clean water reaching up to 3.91 kg m−2 day−1. This study demonstrates a novel strategy for developing advanced solar-driven SAWG materials with efficient water sorption–desorption properties. 相似文献
963.
Bolun Li Xi Huang Xiang Wu Qiong Zuo Yunhao Cao Qi Zhu Yaohui Li Yuanhuan Xu Guanhaojie Zheng Dongcheng Chen Xu-Hui Zhu Fei Huang Hongyu Zhen Lintao Hou Jian Qing Wanzhu Cai 《Advanced functional materials》2023,33(28):2300216
Quasi-two-dimensional (Q-2D) perovskites are emerging as one of the most promising materials for photodetectors. However, a significant challenge to Q-2D perovskites for photodetection is their insufficient charge transport ability, which is mainly attributed to their hybrid low-dimensional n-phase structure. This study demonstrates that evenly-distributed 3D-like phases with vertical orientation throughout the film can greatly facilitate charge transport and suppress charge recombination, outperforming the prevalent phase structure with a vertical dimension gradient. Based on such a phase structure, a Q-2D Ruddlesden−Popper perovskite self-powered photodetector achieving a combination of exceptional figures-of-merit is realized, including a responsivity of 0.45 AW−1, a peak specific detectivity of 2.3 × 1013 Jones, a 156 dB linear dynamic range, and a rise/fall time of 2.89 µs/1.93 µs. The desired phase structure is obtained by utilizing a double-hole transport layer (HTL), combining hydrophobic PTAA and hydrophilic PEDOT: PSS. Besides, the dependence of the hybrid low-dimensional phase structure is also identified on the surface energy of the buried HTL substrate. This study gives insight into the correlation between Q-2D perovskites’ phase structure and performance, providing a valuable design guide for Q-2D perovskite-based photodetectors. 相似文献
964.
Jiayang Liao Xiang Lv Xi-xi Sun Junhua Li Haomin Wang Qiang Chen Hanpeng Lu Duan Wang Jian Bi Jiagang Wu 《Advanced functional materials》2023,33(34):2303637
Although the piezo-catalysis is promising for the environmental remediation and biomedicine, the piezo-catalytic properties of various piezoelectric materials are limited by low carrier concentrations and mobility, and rapid electron-hole pair recombination, and reported regulating strategies are quite complex and difficult. Herein, a new and simple strategy, integrating phase boundary engineering and defect engineering, to boost the piezo-catalytic activity of potassium sodium niobate ((K, Na)NbO3, KNN) based materials is innovatively proposed. Tur strategy is validated by exampling 0.96(K0.48Na0.52)Nb0.955Sb0.045O3-0.04(BixNa4-3x)0.5ZrO3-0.3%Fe2O3 material having phase boundary engineering and conducted the defect engineering via the high-energy sand-grinding. A high reaction rate constant k of 92.49 × 10−3 min−1 in the sand-grinding sample is obtained, which is 2.40 times than that of non-sand-grinding one and superior to those of other representative lead-free perovskite piezoelectric materials. Meanwhile, the sand-grinding sample has remarkable bactericidal properties against Escherichia coli and Staphylococcus aureus. Superior piezo-catalytic activities originate from the enhanced electron-hole pair separation and the increased carrier concentration. This study provides a novel method for improving the piezo-catalytic activities of lead-free piezoelectric materials and holds great promise for harnessing natural energy and disease treatment. 相似文献
965.
966.
In theory, land subsidence measurement results with high accuracy can be obtained by using the Differential Interferometry Synthetic Aperture Radar (D-InSAR) at X-band. In practice, however, the measuring accuracy of D-InSAR at X-band has been seriously affected by some factors, e.g., decorrelation and high deformation gradient. In this work, the monitoring capability of D-InSAR for coal-mining subsidence is evaluated by using SAR data acquired by TerrraSAR-X system. The SAR image registration method for low coherence image pairs, the denoising phase filter for high noise level interferogram and atmospheric effects mitigation method are the key technical aspects which directly influence the measurement results of D-InSAR at X-band. Thus, a robust image registration method, an improved phase filter method and an atmospheric effects mitigation method are proposed in this paper. The proposed image registration method successfully achieves InSAR coregistration, while the amplitude cross-correlation cannot properly coregister low coherence SAR image pairs. Moreover, the time complexity of the proposed image registration method is obviously slighter than that of the Singular Value Decomposition (SVD) method. The comparing experiment results and the unwrapping phase results show that the improved Goldstein filter is more effective than the original Goldstein filter in noise elimination. The atmospheric influence correction experiment results show that the land subsidence areas with atmospheric influence correction are more clarified than that of without at- mospheric influence correction. In summary, the presented methods directly improved the measurement results of D-InSAR at X-band. 相似文献
967.
968.
969.
Group key transfer protocols depend on a mutually trusted key generation center (KGC) to generate group keys and transport group keys to all group members secretly. Generally, KGC encrypts group keys under another secret key shared with each user during registration. In this paper, we propose a novel secure authenticated group key transfer protocol using a linear secret sharing scheme (LSSS) and ElGamal cryptosystem, where KGC broadcasts group key information to all group members. The confidentiality of this transformation is guaranteed by this LSSS and ElGamal cryptosystem. We also provide authentication for transporting this group key. Goals and security threats of our protocol are analyzed in detail. 相似文献
970.
Yingxiang Li Hao Li Junshan Li Bin Tang Shuren Zhang Hetuo Chen Ya Wei 《Journal of Electronic Materials》2014,43(4):1107-1111
Low-loss materials Li2ZnTi3+x O8+2x (LZT) (x = 0, 0.10, 0.17, 0.25, 1.00) were prepared by the conventional solid-state route. The effect of TiO2 ratio on phase composition, microstructure, and the microwave dielectric properties of Li2ZnTi3+x O8+2x ceramics were investigated using x-ray diffraction, scanning electron microscopy, energy-dispersive x-ray spectroscopy, and Vector Network Analyzer. The results revealed that a two-phase system Li2ZnTi3O8-TiO2 was formed. The appropriate content of TiO2 ratio can effectively adjust the temperature coefficient of the resonant frequency (τ f) value from ?14.5 to 0 ppm/ °C without obvious degradation of the microwave dielectric properties. The microwave dielectric properties of the Li2ZnTi3+x O8+2x materials were characterized at microwave frequencies. Typically, the Li2ZnTi3+x O8+2x (x = 0.17) ceramic sintered at 1,160 °C for 5 h showed excellent microwave dielectric properties with ε r = 28.51, Q × f = 58,511 GHz, and τ f = + 2.3 ppm/ °C. 相似文献