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3篇 您的检索式:作者名="Pengqi Yan"
    题名 作者 年代 出处 被引量
1Highly efficient K-Fe/C catalysts derived from metal-organic frameworks towards ammonia synthesis显示文摘Fe-based catalysts have been discovered as the best elementary metal-based heterogeneous catalysts for the ammonia synthesis in industrial application during the last century.Herein,a novel and scalable strategy is developed to prepare the K-promoted Fe/C catalyst with extremely high Fe loading (> 50 wt.%) through pyrolysis of the Fe-based metal-organic framework (MOF) xerogel.The obtained K-Fe/C catalysts exhibited superior activity and stability towards ammonia synthesis.The weight-specific reaction rate of Fe/C with K2O as promoter can achieve 12.4 mmol·g-1·h-1 at 350 ℃ and 30.4 mmol·g-1·h-1 at 400 ℃,approximately four and two times higher than that of the commercial fused-iron catalyst (3.4 mmol·g-1·h-1 at 350 ℃ and 16.7 mmol·g-1·h-1 at 400 ℃) under the same condition,respectively.The excellent performance of K-Fe/C can be ascribed to the inherited structure derived from the metal-organic frame precursors and the promotion of potassium,which can modify the binding energy of reactant molecules on the Fe surface,transfer electrons to iron for effective activation of nitrogen,prevent agglomeration of Fe nanoparticle (NPs) and restrain side reaction of carbon matrix to methane.Pengqi Yan Wenhan Guo Zibin Liang Wei Meng Zhen Yin Siwei Li Mengzhu Li Mengtao Zhang Jie Yan Dequan Xiao Ruqiang Zou Ding Ma 2019Nano Research2019,12,9:4
2Methods for fatigue-life estimation:A review of the current status and future trends显示文摘With the development of modern industry and ever more complex structural loads,the possibility of fatigue failure is increasing.Fatigue analysis can be used to evaluate the service life of components and reduce the probability of accidents.Therefore,the development and application of fatigue-analysis technology have important research significance.This paper collects information from a wide field of literature and summarizes the current status of fatigue-analysis research.It covers related theoretical knowledge,fatigue-life prediction methods,and fatigue design methods and their application scenarios,and it summarizes the challenges and research hotspots in the field.On the basis of this examination,future development directions of fatigue-life prediction methods are proposed.The conclusions will have a certain guiding role in the development of fatigue-analysis methods.Lufan Zhang Boshi Jiang Pengqi Zhang Heng Yan Xiangbo Xu Ruizhuo Liu Jingjing Tang Caixia Ren 2023Nanotechnology and Precision Engineering2023,6,2:0
3Research trends in methods for controlling macro-micro motion platforms显示文摘With ongoing economic,scientific,and technological developments,the electronic devices used in daily lives are developing toward precision and miniaturization,and so the demand for high-precision manufacturing machinery is expanding.The most important piece of equipment in modern high-precision manufacturing is the macro-micro motion platform(M3P),which offers high speed,precision,and efficiency and has macro-micro motion coupling characteristics due to its mechanical design and composition of its driving components.Therefore,the design of the control system is crucial for the overall precision of the platform;conventional proportional–integral–derivative control cannot meet the system requirements,and so M3Ps are the subject of a growing range of modern control strategies.This paper begins by describing the development history of M3Ps,followed by their platform structure and motion control system components,and then in-depth assessments of the macro,micro,and macro-micro control systems.In addition to examining the advantages and disadvantages of current macro-micro motion control,recent technological breakthroughs are noted.Finally,based on existing problems,future directions for M3P control systems are given,and the present conclusions offer guidelines for future work on M3Ps.Lufan Zhang Pengqi Zhang Boshi Jiang Heng Yan 2023Nanotechnology and Precision Engineering2023,6,3:0
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