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Reactive ball-milling synthesis of Co-Fe bimetallic catalyst for efficient hydrogenation of carbon dioxide to value-added hydrocarbons

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Journal of Energy Chemistry 2023年第9期84卷 210-218页

作者： Haipeng Chen Chenwei Wang mengyang zheng Chenlei Liu Wenqiang Li Qingfeng Yang Shixue Zhou Xun Feng College of Chemistry and Chemical Engineering Henan Key Laboratory of Function-Oriented Porous MaterialsLuoyang Normal UniversityLuoyang 471934HenanChina State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021NingxiaChina College of Chemical and Biological Engineering Shandong University of Science and TechnologyQingdao 266590ShandongChina

Catalytic hydrogenation of CO_(2) using renewable hydrogen not only reduces greenhouse gas emissions,but also provides industrial ***,a Co-Fe bimetallic catalyst was developed by a facile reactive ball-milling method for highly active and selective hydrogenation of CO_(2) to value-added *** reacted at 320℃,1.0 MPa and 9600 mL h^(-1) g_(cat)^(-1),the selectivity to light olefin(C_(2)^(=)-C_(4)^(=)) and C_(5)+ species achieves 57.3% and 22.3%,respectively,at a CO_(2) co nversion of 31.4%,which is superior to previous Fe-based *** CO_(2) activation can be promoted by the CoFe phase formed by reactive ball milling of the Fe-Co_(3)O_(4) mixture,and the in-situ Co_(2)C and Fe_(5)C_(2) formed during hydrogenation are beneficial for the C-C coupling *** initial C-C coupling is related to the combination of CO species with the surface carbon of Fe/Co carbides,and the sustained C-C coupling is maintained by self-recovery of defective *** new strategy contributes to the development of efficient catalysts for the hydrogenation of CO_(2) to value-added hydrocarbons.

关键词： Reactive ball milling Co-Fe bimetallic catalyst Carbon dioxide Value-added hydrocarbon C–C coupling reaction

Eureka lemon zinc finger protein ClDOF3.4 interacts with citrus yellow vein clearing virus coat protein to inhibit viral infection

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Journal of Integrative Agriculture 2024年第6期23卷 1979-1993页

作者： Ping Liao Ting Zeng mengyang Huangfu Cairong zheng Jiequn Ren Changyong Zhou Yan Zhou Integrative Science Center of Germplasm Creation in Western China(CHONGQING)Science City Citrus Research InstituteSouthwest UniversityChongqing 400712China National Citrus Engineering Research Center Citrus Research InstituteSouthwest UniversityChongqing 400712China Chongqing Three Gorges Academy of Agricultural Science Chongqing Three Gorges UniversityChongqing 404020China

Citrus yellow vein clearing virus(CYVCV)is a new citrus virus that has become an important factor restricting the development of China’s citrus industry,and the CYVCV coat protein(CP)is associated with viral *** this study,the Eureka lemon zinc finger protein(ZFP)ClDOF3.4 was shown to interact with CYVCV CP in vivo and in *** expression of ClDOF3.4 in Eureka lemon induced the expression of salicylic acid(SA)-related and hypersensitive response marker genes,and triggered a reactive oxygen species burst,ion leakage necrosis,and the accumulation of free ***,the CYVCV titer in ClDOF3.4 transgenic Eureka lemon plants was approximately 69.4%that in control plants 6 mon after inoculation,with only mild leaf chlorotic spots observed in those transgenic *** together,the results indicate that ClDOF3.4 not only interacts with CP but also induces an immune response in Eureka lemon by inducing the SA *** is the first report that ZFP is involved in the immune response of a citrus viral disease,which provides a basis for further study of the molecular mechanism of CYVCV infection.

关键词： citrus yellow vein clearing virus coat protein ClDOF3.4 plant immune response

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多室箱梁桥横隔梁的拉压杆模型及其自动实现

东南大学学报:自然科学版 2023年第5期53卷 886-895页

作者：宋旭明孙凯潘鹏宇唐冕郑梦洋中南大学土木工程学院长沙410075 中铁第四勘察设计院集团有限公司武汉430063

为解决现有规范中单箱多室箱梁支点横隔梁缺乏系统的拉压杆模型建立方法的问题,首先利用拓扑优化功能得到横隔梁拉压杆模型的初步构形,然后根据应力迹线图对模型中的杆件进行补充修正,得到合理的拉压杆模型.研究了支座间距、支座宽度、... 详细信息

为解决现有规范中单箱多室箱梁支点横隔梁缺乏系统的拉压杆模型建立方法的问题,首先利用拓扑优化功能得到横隔梁拉压杆模型的初步构形,然后根据应力迹线图对模型中的杆件进行补充修正,得到合理的拉压杆模型.研究了支座间距、支座宽度、横隔梁宽高比等参数对拉压杆模型的影响,根据支座间距和横隔梁宽高比将单箱三室支点横隔梁的拉压杆模型分为3类,并采用遗传算法实现该3类拉压杆模型的自动构建.结果表明,自动构建方法生成的拉压杆模型与有限元应力积分的计算结果比值在0.95~1.35之间,可以满足支点横隔梁的设计要求.所提出的方法可以实现自动构建多室箱梁横隔梁的拉压杆模型,对支点横隔梁的受力分析及设计计算具有一定的实用价值.

关键词：横隔梁拉压杆模型拓扑优化应力迹线遗传算法自动实现

Plate tectonics in the Archean:Observations versus interpretations

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Science China Earth Sciences 2024年第1期67卷 1-30页

作者： YongFei zheng School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Crust-Mantle Materials and Environment Chinese Academy of SciencesHefei 230026China Center of Excellence for Comparative Planetology Chinese Academy of SciencesHefei 230026China

Plate tectonics theory,established in the 1960s,has been successful in explaining many geological phenomena,processes and events that occurred in the ***,the theory has often struggled to provide a coherent framework in interpreting geological records in continental interior and Precambrian *** dealing with the relationship between plate tectonics and continental geology,continental interior tectonics was often separated from continental margin tectonics in the inheritance and development of their structure and *** separation led to the illusion that the plate tectonics theory is not applicable to Precambrian geology,particularly in explaining the fundamental geological characteristics of Archean *** this illusion does not mean that the Archean continental crust did not originate from a regime of plate tectonics,it led to the development of alternative tectonic models,often involving vertical movements under a regime of stagnant lid tectonics,including not only endogenous processes such as gravitational sagduction,mantle plumes and heat pipes but also exogenous processes such as bolide *** vertical processes were not unique to the Archean but persisted into the *** result from mantle poloidal convection at different depths,not specific to any particular *** the plate tectonics theory from the traditional kinematic model in the 20th century to a holistic kinematic-dynamic model in the 21st century and systematically examining the vertical transport of matter and energy at plate margins,it is evident that plate tectonics can explain the common geological characteristics of Archean cratons,such as lithological associations,structural patterns and metamorphic *** deciphering the structure and composition of convergent plate margins as well as their dynamics,the formation and evolution of continental crust since the Archean can be divided into ancient plate tectonics in the Preca

关键词： Plate tectonics Archean geology Continental origin Crustal reworking Plate interior Plate margin

Safe Motion Planning and Control Framework for Automated Vehicles with Zonotopic TRMPC

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Engineering 2024年第2期33卷 146-159页

作者： Hao zheng Yinong Li Ling zheng Ehsan Hashemi State Key Laboratory of Mechanical Transmissions College of Mechanical and Vehicle EngineeringChongqing UniversityChongqing 400044China Department of Mechanical Engineering University of AlbertaEdmontonAB T6G 2H5Canada

Model mismatches can cause multi-dimensional uncertainties for the receding horizon control strategies of automated vehicles(AVs).The uncertainties may lead to potentially hazardous behaviors when the AV tracks ideal trajectories that are individually optimized by the AV's planning *** address this issue,this study proposes a safe motion planning and control(SMPAC)framework for *** the control layer,a dynamic model including multi-dimensional uncertainties is established.A zonotopic tube-based robust model predictive control scheme is proposed to constrain the uncertain system in a bounded minimum robust positive invariant set.A flexible tube with varying cross-sections is constructed to reduce the controller *** the planning layer,a concept of safety sets,representing the geometric boundaries of the ego vehicle and obstacles under uncertainties,is *** safety sets provide the basis for the subsequent evaluation and ranking of the generated *** efficient collision avoidance algorithm decides the desired trajectory through the intersection detection of the safety sets between the ego vehicle and obstacles.A numerical simulation and hardware-in-the-loop experiment validate the effectiveness and real-time performance of the *** result of two driving scenarios indicates that the SMPAC can guarantee the safety of automated driving under multi-dimensional uncertainties.

关键词： Automated vehicles Automated driving Motion planning Motion control Tube MPC Zonotope

Discovery of the Significant Impacts of Swell Propagation on Global Wave Climate Change

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Journal of Ocean University of China 2024年第3期23卷 594-604页

作者： zheng Chongwei Dalian Naval Academy Dalian 116018China Marine Resources and Environment Research Group on the Maritime Silk Road Dalian 116018China

This study compared the differences in the wave climate in the South China Sea and North Indian Ocean under these two datasets:ERA-40 wave reanalysis and Mei’s hindcast wave *** the numerical calculation of regional ocean waves,the wave climate characteristics exhibited significant bias if the influence of external swells(swells from afar)was not fully considered,which may provide an incorrect basis for global climate change analysis.1)The trends of the significant wave height(SWH)obtained from the two datasets showed significant differences,such as those of the Bay of Bengal and the Java Sea in *** the past 45 years,SWH from ERA-40(SWH-ERA)exhibited a significant annual increase in low-latitude waters of the North Indian Ocean(0.2-0.6 cm yr^(-1))and South China Sea(0.2-0.8 cm yr^(-1)).2)In the Bay of Bengal,the SWH-ERA in each month was generally 0.5 m higher than the SWH from Mei’s hindcast wave data(SWH-Mei)and can reach 1.0 m higher in some months.3)In the Bay of Bengal,SWH-ERA and SWH-Mei increased significantly at annual rates of 0.13 and 0.27 cm yr^(-1),*** increasing trend was mainly reflected after ***-ERA showed a trough in 1975(1.33 m)and a crest in 1992(1.83 m),which were not reflected in SWH-Mei.

关键词： wave climate climatic trend monthly variation annual variation external swell

A positive trend in the stability of global offshore wind energy

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Acta Oceanologica Sinica 2024年第1期43卷 123-134页

作者： Chongwei zheng Dalian Naval Academy Dalian 116018China Marine Resources and Environment Research Group on the Maritime Silk Road Dalian 116018China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China

The recognition on the trend of wind energy stability is still extremely rare,although it is closely related to acquisition efficiency,grid connection,equipment lifetime,and costs of wind energy *** the 40-year(1979–2018)ERA-Interim data from the European Center for Medium-Range Weather Forecasts,this study presented the spatial-temporal distribution and climatic trend of the stability of global offshore wind energy as well as the abrupt phenomenon of wind energy stability in key regions over the past 40 years with the climatic analysis method and Mann-Kendall(M-K)*** results show the following 5 points.(1)According to the coefficient of variation(C_(v))of the wind power density,there are six permanent stable zones of global offshore wind energy:the southeast and northeast trade wind zones in the Indian,Pacific and Atlantic oceans,the Southern Hemisphere westerly,and a semi-permanent stable zone(North Indian Ocean).(2)There are six lowvalue zones for both seasonal variability index(S_(v))and monthly variability index(M_(v))globally,with a similar spatial distribution as that of the six permanent stable zones.M_(v) and S_(v) in the Arabian Sea are the highest in the world.(3)After C_(v),M_(v) and S_(v) are comprehensively considered,the six permanent stable zones have an obvious advantage in the stability of wind energy over other sea areas,with C_(v) below 0.8,M_(v) within 1.0,and S_(v) within 0.7 all the year round.(4)The global stability of offshore wind energy shows a positive climatic trend for the past four decades.C_(v),M_(v) and S_(v) have not changed significantly or decreased in most of the global ocean during 1979 *** is,wind energy is flat or more stable,while the monthly and seasonal variabilities tend to shrink/smooth,which is beneficial for wind energy utilization.(5)C_(v) in the low-latitude Pacific and M_(v) and S_(v) in both the North Indian Ocean and the low-latitude Pacific have an obvious abrupt phenomenon at the end of

关键词： global oceans wind energy stability spatial-temporal distribution climatic trend

Wind power and sand/dust storms

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 175-176页

作者： XiaoJing zheng Center for Particle-Laden Turbulence Lanzhou UniversityLanzhou 730000China

Sand/dust storms,a globally prevalent catastrophic weather phenomenon,can cause significant erosion to the climate and ecological *** high concentration of sand particles they carry not only impacts atmospheric qualit... 详细信息

关键词： Wind power and sand/dust storms

Damping Characteristic Analysis and Optimization of Wind-thermal-bundled Power Transmission by LCC-HVDC Systems

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 299-312页

作者： Liwen zheng Shiying Ma the Power System Department China Electric Power Research InstituteBeijing 100192China

With the rapid development of renewable energy,wind-thermal-bundled power transmission by line-commutated converter based high-voltage direct current(LCC-HVDC)systems has been widely *** dynamic interaction mechanisms among permanent magnet synchronous generators(PMSGs),synchronous generators(SGs),and LCC-HVDC system become *** deal with this issue,a path analysis method(PAM)is proposed to study the dynamic interaction mechanism,and the damping reconstruction is used to analyze the damping characteristic of the ***,based on the modular modeling,linearized models for the PMSG subsystem,the LCC-HVDC subsystem,and the SG subsystem are ***,based on the closed-loop transfer function diagram of the system,the disturbance transfer path and coupling relationship among subsystems are analyzed by the PAM,and the damping characteristic analysis of the SG-dominated oscillation mode is studied based on the damping *** with the PAM,the small-signal model of the system is obtained and eigenvalue analysis results are ***,the effect of the control parameters on the damping characteristic is analyzed and the conclusions are verified by time-domain ***,the penalty functions of the oscillation modes and decay modes are taken as the objective function,and an optimization strategy based on the Monte Carlo method is proposed to solve the parameter optimization *** simulation results are presented to validate the effectiveness of the proposed strategy.

关键词： Wind-thermal-bundled power transmission line-commutated converter based high-voltage direct current(LCC-HVDC) path analysis method(PAM) damping characteristic analysis Monte Carlo method