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991.
Mechanical Strain‐Tunable Microwave Magnetism in Flexible CuFe2O4 Epitaxial Thin Film for Wearable Sensors 下载免费PDF全文
Wenlong Liu Ming Liu Rong Ma Ruyi Zhang Wenqing Zhang Dapeng Yu Qing Wang Jiannong Wang Hong Wang 《Advanced functional materials》2018,28(10)
Purely mechanical strain‐tunable microwave magnetism device with lightweight, flexible, and wearable is crucial for passive sensing systems and spintronic devices (noncontact), such as flexible microwave detectors, flexible microwave signal processing devices, and wearable mechanics‐magnetic sensors. Here, a flexible microwave magnetic CuFe2O4 (CuFO) epitaxial thin film with tunable ferromagnetic resonance (FMR) spectra is demonstrated by purely mechanical strains, including tensile and compressive strains, on flexible fluorophlogopite (Mica) substrates. Tensile and compressive strains show remarkable tuning effects of up‐regulation and down‐regulation on in‐plane FMR resonance field (Hr), which can be used for flexible tunable resonators and filters. The out‐of‐plane FMR spectra can also be tuned by mechanical bending, including Hr and absorption peak. The change of out‐of‐plane FMR spectra has great potential for flexible mechanics‐magnetic deformation sensors. Furthermore, a superior microwave magnetic stability and mechanical antifatigue character are obtained in the CuFO/Mica thin films. These flexible epitaxial CuFO thin films with tunable microwave magnetism and excellent mechanical durability are promising for the applications in flexible spintronics, microwave detectors, and oscillators. 相似文献
992.
探讨了中国3G牌照何时发放、发放数量、牌照与标准是否捆绑、3G产业链如何搭建、频率如何分配、市场容量和终端等问题,并对此提出了建设性的意见。 相似文献
993.
Sihai Chen Xinjian Yi Hong Ma Tao Xiong Hongcheng Wang Caijun Ke 《Journal of Infrared, Millimeter and Terahertz Waves》2004,25(1):157-163
This paper presents a method to make vanadium dioxide (VO2) crystallites on silicon substrates by reactive ion beam sputtering. The thickness of the thin film is about 100nm. The phase transition temperature of VO2 is 65°C. The transmittance of the semiconducting phase VO2 is about 50% and it is reduced to as low as 3% in metal phase at the infrared wavelenghth spectrum. The extinction ratio of the optical switches is 12dB. and the insertion loss is of 1-2dB. The switching time is about 1ms. 相似文献
994.
针对美国现行军用标准MIL-STD-461F的新增内容CS106,以及与MIL-STD-461D/462D、MIL-STD-461E的差异,从测试一般要求和测试详细要求两个方面进行了介绍。提出了实验室的对应措施。 相似文献
995.
Lubin Yang Xiaowei Wang Xiaomin Cheng Yongzheng Zhang Cheng Ma Yayun Zhang Jitong Wang Wenming Qiao Licheng Ling 《Advanced functional materials》2023,33(38):2303705
Lithium-sulfur batteries (LSBs) suffer from uncontrollable shuttling behavior of lithium polysulfides (LiPSs: Li2Sx, 4 ≤ x ≤8) and the sluggish reaction kinetics of bidirectional liquid-solid transformations, which are commonly coped through a comprehensive adsorption-catalysis strategy. Herein, a unique Fe N V pre-coordination is introduced to regulate the content of “dissociative Fe3+” in liquid phase, realizing the successful construction of N-doped micro-mesoporous “urchin-like” hollow carbon nanospheres decorated with single atom Fe-N4 sites and VN nanoparticles (denoted as SA-Fe/VN@NMC). The strong chemisorption ability toward LiPSs and catalyzed Li2S decomposition behavior on VN, along with the boosted reaction kinetics for sulfur reduction on SA-Fe sites are experimentally and theoretically evidenced. Moreover, the nanoscale-neighborhood distribution of VN and SA-Fe active sites presents synergistic effect for the anchoring-reduction-decomposition process of sulfur species. Thus SA-Fe/VN@NMC presents an optimized adsorption-catalysis effect for the whole sulfur conversion. Therefore, the SA-Fe/VN@NMC based Li-S cells exhibit high cyclic stability (a low decay of 0.024% per cycle over 700 cycles at 1 C, sulfur content: 70 wt%) and considerable rate performance (683.2 mAh g−1 at 4 C). Besides, a high areal capacity of 5.06 mAh cm−2 is retained after 100 cycles under the high sulfur loading of 5.6 mg cm−2. This work provides a new perspective to design the integrated electrocatalysts comprising hetero-formed bimetals in LSBs. 相似文献
996.
Afshin Behzadan Alagan Anpalagan Isaac Woungang Bobby Ma Han‐Chieh Chao 《Wireless Communications and Mobile Computing》2015,15(16):2020-2037
A utility‐based distributed data routing algorithm is proposed and evaluated for heterogeneous wireless sensor networks. It is energy efficient and is based on a game‐theoretic heuristic load‐balancing approach. It runs on a hierarchical graph arranged as a tree with parents and children. Sensor nodes are considered heterogeneous in terms of their generated traffic, residual energy and data transmission rate and the bandwidth they provide to their children for communication. The proposed method generates a data routing tree in which child nodes are joined to parent nodes in an energy‐efficient way. The principles of the Stackelberg game, in which parents as leaders and children as followers, are used to support the distributive nature of sensor networks. In this context, parents behave cooperatively and help other parents to adjust their loads, while children act selfishly. Simulation results indicate the proposed method can produce on average more load‐balanced trees, resulting in over 30% longer network lifetime compared with the cumulative algorithm proposed in the literature. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
997.
Harvesting Lost Photons: Plasmon and Upconversion Enhanced Broadband Photocatalytic Activity in Core@Shell Microspheres Based on Lanthanide‐Doped NaYF4, TiO2, and Au 下载免费PDF全文
Zhenhe Xu Marta Quintanilla Fiorenzo Vetrone Alexander O. Govorov Mohamed Chaker Dongling Ma 《Advanced functional materials》2015,25(20):2950-2960
Efficiently harvesting solar energy for photocatalysis remains very challenging. Rational design of architectures by combining nanocomponents of radically different properties, for example, plasmonic, upconversion, and photocatalytic properties, offers a promising route to improve solar energy utilization. Herein, the synthesis of novel, plasmonic Au nanoparticle decorated NaYF4:Yb3+, Er3+, Tm3+‐core@porous‐TiO2‐shell microspheres is reported. They exhibit high surface area, good stability, broadband absorption from ultraviolet to near infrared, and excellent photocatalytic activity, significantly better than the benchmark P25 TiO2. The enhanced activity is attributed to synergistic effects from nanocomponents arranged into the nanostructured architecture in such a way that favors the efficient charge/energy transfer among nanocomponents and largely reduced charge recombination. Optical and energy‐transfer properties are modeled theoretically to support our interpretations of catalytic mechanisms. In addition to yielding novel materials and interesting properties, the current work provides physical insights that can contribute to the future development of plasmon‐enhanced broadband catalysts. 相似文献
998.
A serial concatenated decoding algorithm with dynamic threshold is proposed for low‐density parity‐check codes with short and medium code lengths. The proposed approach uses a dynamic threshold to select a decoding result from belief propagation decoding and order statistic decoding, which improves the performance of the decoder at a negligible cost. Simulation results show that, under a high SNR region, the proposed concatenated decoder performs better than a serial concatenated decoder without threshold with an Eb/N0 gain of above 0.1 dB. 相似文献
999.
研究了在水中兵器回收试验中采用发烟技术进行目标指示所需要解决的关键技术。采用材料的耐压技术、活塞的密封技术、火药的气动技术等设计出来的发烟装置,经多型号产品试验证实了该技术可极大地提高水中兵器返回水面时的搜寻效率。 相似文献
1000.