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21.
Jing‐Qi Chi Xiao‐Jun Zeng Xiao Shang Bin Dong Yong‐Ming Chai Chen‐Guang Liu Melinda Marin Yadong Yin 《Advanced functional materials》2019,29(33)
Rational design and controllable synthesis of well‐defined nanostructures with high stability and Pt‐like activity for hydrogen evolution reaction (HER) are critical for renewable energy conversion. Herein, a unique pyrolysis strategy is demonstrated for the synthesis of RhPx nanoparticles (NPs) in N, P co‐doped thin carbon nanoshells (RhPx@NPC nanoshells) that display high electrocatalytic activity and stability over a wide pH range. This strategy involves simultaneous phosphorization and pyrolysis processes that can produce highly‐dispersed RhPx NPs within N, P co‐doped carbon nanoshells and at the same time induce thinning of carbon nanoshells from inside out. The resulting RhPx@NPC nanoshells not only possess Pt‐like activity for HER with low overpotentials to achieve 10 mA cm?2 (22 mV in 0.5 m H2SO4, 69 mV in 1.0 m KOH, and 38 mV in 1.0 m phosphate buffered saline (PBS)) but also provide long‐term durability in a wide pH range. The remarkable HER performance of RhPx@NPC nanoshells is ascribed to the high surface area, abundant mesoporosity, strong catalyst–support interaction, ultrathin carbon encapsulation, and N, P co‐doping. This work provides an effective strategy for designing heterostructured electrocatalysts with high catalytic activity and stability desired for reactions that may occur under harsh conditions. 相似文献
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Wireless Networks - Nowadays, people trade electricity through centralized companies or organizations which is vulnerable to cyber attacks and incapable of coping with increasing demands from... 相似文献
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电子信息工程专业建设与改革的实践 总被引:4,自引:0,他引:4
简要回顾扬州大学电子信息工程专业创办历史,主要介绍了在专业建设和教学改革方面采取的一些措施,主要包括成立专业指导委员会、设立强化班、试行按专业大类招生、开展双语教学、进行教材建设和实验室建设等。通过近几年的专业建设,该专业得到长足的发展,教学质量不断提高。最后简要介绍今后在专业建设方面的工作思路。 相似文献
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重复使用运载器 (RLV)将大幅度降低现役航天运载器的发射准备时间、成本 ,并提高其可靠性、安全性 ,是航天运输系统的发展方向。制导、导航与控制 (GN&C)系统是RLV的核心技术之一 ,先进的RLV的GN&C技术不仅能缩短设计周期、降低成本 ,而且对复杂多变的飞行环境具有较强的鲁棒性 ,从而提高了飞行器的安全性。指出了RLV的GN&C系统的要求、特点 ,总结了近年来该领域的研究成果 ,提出了下一步需研究的问题。 相似文献
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Xu Shuiqing Chai Yi Hu Youqiang Huang Lei 《International Journal of Electronics》2018,105(6):1051-1062
Nonuniform sampling can be encountered in various practical processes because of random events or poor timebase. The analysis and applications of the nonuniform sampling for deterministic signals related to the linear canonical transform (LCT) have been well considered and researched, but up to now no papers have been published regarding the various nonuniform sampling theorems for random signals related to the LCT. The aim of this article is to explore the nonuniform sampling and reconstruction of random signals associated with the LCT. First, some special nonuniform sampling models are briefly introduced. Second, based on these models, some reconstruction theorems for random signals from various nonuniform samples associated with the LCT have been derived. Finally, the simulation results are made to prove the accuracy of the sampling theorems. In addition, the latent real practices of the nonuniform sampling for random signals have been also discussed. 相似文献
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《电路理论基础》教材第三版的修订工作正在进行。本文介绍了本次修订的策略,与第二版相比的主要变化,旨在与读者和同行教师进行广泛交流,进一步完善修订工作。 相似文献
30.
Zhenkun Lin Nirmal Goswami Tiantian Xue Osburg Jin Huang Chai Hejie Xu Yuxin Liu Yu Su Jianping Xie 《Advanced functional materials》2021,31(51):2105662
Metal nanoclusters (NCs) have recently attracted great interest in biomedical applications due to their ultrasmall size, good biocompatibility, and unique molecule-like physical and chemical properties. Metal NCs can be rationally designed and integrated with various targeting moieties to achieve unique physicochemical properties and functions. For therapeutic applications, these multifunctional surface-modified NCs can provide distinctive advantages over native metal NCs, such as improved therapeutic effects and reduced side effects. In this review, the design principles of targeting strategies for metal NCs and their composites, including passive and active targeting, and physical and chemical targeting are first discussed. The authors then focus on the recent achievements in the application of metal NCs in targeted therapeutics, including chemotherapy, phototherapy, and radiotherapy. Finally, the authors’ perspectives on the challenges and opportunities of developing metal NCs in targeted therapeutics, further paving their way for potential clinical applications are provided. 相似文献