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111.
Yanying Li Qiwen Zhang Xiaoran Zhao Haofei Wu Xinyao Wang Yuqiao Zeng Qing Chen Mingwei Chen Pan Liu 《Advanced functional materials》2023,33(17):2370105
The development of low-cost and effective oxygen evolution reaction (OER) electrocatalysts to expedite the slow kinetics of water splitting is crucial for increasing the efficiency of energy conversion from electricity to hydrogen fuel. Herein, 3D bicontinuous nanoporous Co@CoO/RuO2 composites with tunable sizes and chemical compositions are fabricated by introducing vapor phase dealloying of cobalt-based alloys. The influence of physical parameters on the formation of nanoporous Co substrates with various feature ligament sizes is systematically investigated. The CoO/RuO2 shell is constructed by integrating a thin layer of RuO2 on the inner surface of nanoporous Co, where the CoO interlayer is formed by annealing oxidization. The composite catalyst delivers an ultralow overpotential of 198 mV at 10 mA cm−2, Tafel slope of 57.1 mV dec−1, and long-term stability of 50 h. The superior OER activity and fast reaction kinetics are attributed to charge transfer through the coupling of Co O Ru bonds at the interface and the excellent nanopore connectivity, while the durability originates from the highly stable CoO/RuO2 interface. 相似文献
113.
Wang Ruo-Bin Wang Wei-Feng Xu Lin Pan Jeng-Shyang Chu Shu-Chuan 《Wireless Networks》2022,28(8):3411-3428
Wireless Networks - Improving localization performance is one of the critical issues in Wireless Sensor Networks (WSN). As a range-free localization algorithm, Distance Vector-Hop(DV-Hop) is... 相似文献
114.
Yibiao Pan 《Proceedings of the American Mathematical Society》1996,124(9):2821-2825
We consider boundedness properties of oscillatory singular integrals on and Hardy spaces. By constructing a phase function, we prove that boundedness may fail while boundedness holds for all . This shows that the theory and theory for such operators are fundamentally different.
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The generalized Landweber iteration with a variable shaping matrix is used to solve the large linear system of equations arising in the image reconstruction problem of emission tomography. The method is based on the property that once a spatial frequency image component is almost recovered within in in the generalized Landweber iteration, this component will still stay within in during subsequent iterations with a different shaping matrix, as long as this shaping matrix satisfies the convergence criterion for the component. Two different shaping matrices are used: the first recovers low-frequency image components; and the second may be used either to accelerate the reconstruction of high-frequency image components, or to attenuate these components to filter the image. The variable shaping matrix gives results similar to truncated inverse filtering, but requires much less computation and memory, since it does not rely on the singular value decomposition. 相似文献
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通过表面摩擦、施加外电场(或磁场)和应力剪切等手段使液晶单体取向后进行光聚合反应是制备高度取向、高度均匀和高度透明高分子液晶膜的重要方法。它在高分子非线性光学材料、导电商分子材料和光纤涂层等领域中具有广泛的应用前景。 相似文献