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Nano Research 2023年第4期16卷 5938-5945页

作者： Beibei Yang Sheng Tao xuefei liu Jun Lu State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Tianjin University Tianjin 300072China

Oxygen reduction reaction(ORR)plays a pivotal role in advanced electrochemical energy conversion ***,the ORR conversion efficiency is extremely *** major obstacles originate from the adsorption and activation of O_(2)on the electrode surface.A novel nanocomposite catalyst,photosensitizers(PS)meso-tetraphenylporphyrin iron(III)chloride(FePcCl)/NiCoFe-layered double hydroxides(NiCoFe-LDHs)is designed in this ***,owing to excellent oxygen molecules activation ability and remarkable illumination absorption feature,FePcCl/NiCoFe-LDHs is employed to uncover the relationship between the intrinsic ORR activity and PS ***,the reaction mechanism of singlet 1O_(2)is proposed owing to the combination of electrochemical ORR catalysed via LDHs and *** boosted cathodic ORR properties exhibit singlet 1O_(2)dependent response arising from the synergistic effect to selectively produce active intermediates in alkaline *** work imparts the promising new mechanism about the high 4-electron ORR selectivity via material design,which will guide the development of photo-assisted energy conversion devices.

关键词： oxygen reduction reaction singlet 1O_(2) photosensitizers photo-assisted energy conversion layered double hydroxides

Synergistically Toughening Effect of SiC Whiskers and Nanoparticles in Al_2O_3-based Composite Ceramic Cutting Tool Material

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Chinese Journal of Mechanical Engineering 2016年第5期29卷 977-982页

作者： liu xuefei liu Hanlian HUANG Chuanzhen WANG Limei ZOU Bin ZHAO Bin Centre for Advanced Jet Engineering Technologies School of Mechanical EngineeringShandong University School of Mechanical and Electrical Engineering Qilu Institute of Technolegy Key Laboratory of High Efficiency and Clean Mechanical Manufacture of Ministry of Education Shandong University

In recent decades, many additives with different characteristics have been applied to strengthen and toughen Al2O3-based ceramic cutting tool materials. Among them, SiC whiskers and SiC nanoparticles showed excellent performance in improving the material properties. While no attempts have been made to add SiC whiskers and SiC nanoparticles together into the ceramic matrix and the synergistically toughening effects of them have not been studied. An Al2O3-SiCw-SiC np advanced ceramic cutting tool material is fabricated by adding both one-dimensional SiC whiskers and zero-dimensional SiC nanoparticles into the Al2O3 matrix with an effective dispersing and mixing process. The composites with 25 vol% SiC whiskers and 25 vol% SiC nanoparticles alone are also investegated for comparison purposes. Results show that the Al2O3-SiCw-SiCnp composite with both 20 vo1% SiC whiskers and 5 vol% SiC nanoparticles additives have much improved mechanical properties. The flexural strength of Al2O3-SiCw-SiCnp is 730＋ 95 MPa and fracture toughness is 5.6 ± 0.6 MPa.m1/2. The toughening and strengthening mechanisms of SiC whiskers and nanoparticles are studied when they are added either individually or in combination. It is indicated that when SiC whiskers and nanoparticles are added together, the grains are further refined and homogenized, so that the microstructure and fracture mode ratio is modified. The SiC nanoparticles are found helpful to enhance the toughening effects of the SiC whiskers. The proposed research helps to enrich the types of ceramic cutting tool and is benefit to expand the application range of ceramic cutting tool.

关键词： Al2O3-based ceramic cutting tool materials SiC whiskers SiC nanoparticles mechanical properties,toughening and strengthening mechanisms

High-entropy layered oxides nanosheets for highly efficient photoelectrocatalytic reduction of CO_(2)and application research

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Nano Research 2023年第4期16卷 4775-4785页

作者： xuefei liu Xiaoyan Wang Beibei Yang Junzheng Zhang Jun Lu State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

High-entropy oxides receive significant attention owing to their“four effects”.However,they still suffer from harsh construction conditions such as high temperature and high pressure and present a block-like ***,in this work,Ni-Mn-Cu-Co-Fe-Al high-entropy layered oxides(HELOs)with a layered nanosheet structure were constructed by a simple pathway of topological transformation under relatively low temperature(300℃)with six-membered Ni-Mn-Cu-Co-Fe-Al layered double hydroxides(LDHs)precursors,which exhibited an outstanding activity and excellent selectivity for CO_(2)photoelectroreduction(obtaining the highest carbon monoxide yield of 909.55μmol·g^(−1)·h^(−1)under−0.8 V *** hydrogen electrode(RHE),which is almost twice that of pure electrocatalysis).In addition,the charging voltage of a photo-assisted Zn-CO_(2)battery with HELOs as electrode was reduced from 2.62 to 2.40 V;the discharging voltage of the battery was increased from 0.51 to 0.59 V with the assistance of *** improvement of round-trip efficiency of the battery indicates that light played a positive role in both the charging and discharging *** study not only lays an important foundation for the development of high-entropy oxides but also expands their application in the field of photoelectrochemistry.

关键词： high-entropy layered oxides(HELOs) CO_(2)reduction layered double hydroxides(LDHs) photoelectrocatalytic

Late Mesozoic magmatism in the Jiaodong Peninsula,East China:Implications for crust-mantle interactions and lithospheric thinning of the eastern North China Craton

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Geoscience Frontiers 2020年第3期11卷 895-914页

作者： Yayun Liang xuefei liu Qingfei Wang Rui Zhao Yao Ma School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences(Beijing)Beijing100083China

A section from the Linglong gold deposit on the northwestern Jiaodong Peninsula,East China,containing Late Mesozoic magmatic rocks from mafic and intermediate dikes and felsic intrusions,was chosen to investigate the lithospheric evolution of the eastern North China Craton(NCC).Zircon U-Pb data showed that low-Mg adakitic monzogranites and granodiorite intrusions were emplaced during the Late Jurassic(~145 Ma) and late Early Cretaceous(112-107 Ma),respectively;high-Mg adakitic diorite and mafic dikes were also emplaced during the Early Cretaceous at^139 Ma and ~118 Ma,and 125-145 Ma and 115-120 Ma,*** geochemical data,including whole-rock major and trace element compositions and Sr-Nd-Pb isotopes,imply that the mafic dikes originated from the partial melting of a lithospheric mantle metasomatised through hydrous fluids from a subducted oceanic ***-Mg adakitic monzogranites and granodiorite intrusions originated from the partial melting of the thickened lower crust of the NCC,while high-Mg adakitic diorite dikes originated from the mixing of mafic and felsic *** Mesozoic magmatism showed that lithosphere-derived melts showed a similar source depth and that crust-derived felsic melts originated from the continuously thickened lower crust of the Jiaodong Peninsula from the Late Jurassic to Early *** infer that the lower crust of the eastern NCC was thickened through compression and subduction of the Palaeo-Pacific plate beneath the NCC during the Middle *** rollback of the plate from ~160 Ma resulted in lithospheric thinning and accompanied Late Mesozoic magmatism.

关键词： Late mesozoic magmatism Lithospheric thinning Jiaodong peninsula Eastern North China Craton

Understanding the hydrogen evolution reaction activity of doped single-atom catalysts on two-dimensional GaPS_(4) by DFT and machine learning

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Journal of Energy Chemistry 2023年第6期81卷 93-100,I0004页

作者： Tianyun liu Xin Zhao xuefei liu Wenjun Xiao Zijiang Luo Wentao Wang Yuefei Zhang Jin-Cheng liu College of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025GuizhouChina Center for Rare Earth and Inorganic Functional Materials School of Materials Science and Engineering&National Institute for Advanced MaterialsNankai UniversityTianjin 300350China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China College of Information Guizhou University of Finance and EconomicsGuiyang 550025GuizhouChina Guizhou Provincial Key Laboratory of Computational Nano-Material Science Guizhou Education UniversityGuiyang 550018GuizhouChina

As a zero-carbon fuel,hydrogen can be produced via electrochemical water splitting using clean electric energy by the hydrogen evolution reaction(HER)*** ultimate goal of HER catalyst is to replace the expensive Pt metal benchmark with a cheap one with equivalent *** this work,we investigated the possibility of HER process on single-atom catalysts(SACs)doped on two-dimensional(2D)GaPS_(4)materials,which have a large intrinsic band gap that can be regulated by doping and tensile *** on the machine learning regression analysis,we can expand the prediction of HER performance to more catalysts without expensive DFT *** electron affinity and first ionization energy are the two most important descriptors related to the HER ***,constrain molecular dynamics with solvation models and constant potentials were applied to understand the dynamics barrier of HER process of Pt SAC on GaPS_(4)*** findings not only provide important insights into the catalytic properties of single-atom catalysts on GaPS_(4)2D materials,but also provides theoretical guidance paradigm for exploration of new catalysts.

关键词： Two-dimensional GaPS_(4) Hydrogen evolution reaction Single-atom catalysis First-principles calculation Machine learning

Magnetically recyclable Pd/γ-AlOOH@Fe_3O_4 catalysts and their catalytic performance for the Heck coupling reaction

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Science China Chemistry 2014年第6期57卷 866-872页

作者： YANG Hao JI ShengFu liu xuefei ZHANG DanNi SHI Da State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

Novel magnetically recyclable Pd/γ-AlOOH@Fe3O4 catalysts were prepared using γ-AlOOH@Fe3O4 as a magnetic supporter and nano-Pd particles as the active catalytic *** structure of the catalysts was characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),N2 adsorption-desorption,and a vibration sample magnetometer(VSM).The catalytic activity and recyclability for the Heck coupling reaction were *** showed that the magnetic γ-AlOOH@Fe3O4 possessed a core-shell structure,as well as that the nano-Pd particles were 6–8 nm and had been well dispersed in the γ-AlOOH *** the Heck coupling reactions,the magnetic Pd/γ-AlOOH@Fe3O4 catalysts exhibited good catalytic activity and *** the(0.021 mol%)Pd/γ-AlOOH@Fe3O4 catalyst,the bromobenzene conversion and product yield reached about 100%and 96.3%,respectively,under a 120°C reaction temperature and 12 h reaction *** being recycled 8 times,the conversion of bromobenzene and the recovery of the catalyst were about 90%and 93%,*** nano-Pd particles were kept well dispersed in the used Pd/γ-AlOOH@Fe3O4 catalyst.

关键词： magnetic Pd/γ-AlOOH@Fe3O4 Heck reaction recyclable

Design and Theoretical Research on Aerial-Aquatic Vehicles:A Review

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Journal of Bionic Engineering 2023年第6期20卷 2512-2541页

作者： Yi Sun xuefei liu Kai Cao Huan Shen Qian Li Guangming Chen Jiajun Xu Aihong Ji Lab of Locomotion Bioinspiration and Intelligent Robots College of Mechanical and Electrical EngineeringState Key Laboratory of Mechanics and Control for Aerospace StructuresNanjing University of Aeronautics and Astronautics29 Yudao StreetNanjing210016China State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China

With the rapid development of unmanned aerial and underwater vehicles,various tasks,such as biodiversity monitoring,surveying,and mapping,as well as,search and rescue can now be completed in a single medium,either underwater or in the *** systematically examining the water–air cross-medium locomotion of organisms,there has been growing interest in the development of aerial-aquatic *** goal of this review is to provide a detailed outline of the design and cross-medium theoretical research of the existing aerial-aquatic vehicles based on the research on the organisms capable of transiting between water and *** these designs and theoretical frameworks have been validated in many aerial-aquatic vehicles,there are still many problems that need to be addressed,such as inflexible underwater motion and unstable medium *** a result,supplementation of the existing cross-medium biomimetic research,vehicle design,power selection,and cross-medium theory is urgently required to optimize the key technologies in ***,by summarizing the existing designs and theoretical approaches on aerial-aquatic vehicles,including biomimetic research on water–air cross-medium locomotion in nature,different power selections,and cross-medium theoretical research,the relative problems and development trends on aerial-aquatic vehicles were thoroughly explored,providing significant help for the subsequent research process.

关键词： Aerial-aquatic vehicle Cross-medium motion Power selection Control theory Biomimetic

Pathogen evolution, prevention/control strategy and clinical features of COVID-19: experiences from China

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Frontiers of Medicine 2023年第6期17卷 1030-1046页

作者： Dong Wei Yusang Xie xuefei liu Rong Chen Min Zhou Xinxin Zhang Jieming Qu IDepartment of Infectious Diseases Research Laboratory of Clinical VirologyRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Department of Pulmonary and Critical Care Medicine Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Institute of Respiratory Diseases Shanghai Jiao Tong University School of MedicineShanghai 200025China Shanghai Key Laboratory of Emergency Prevention Diagnosis and Treatment of Respiratory InfectiousDiseasesShanghai 200025China

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)was reported at the end of 2019 as a worldwide health concern causing a pandemic of unusual viral pneumonia and many other organ damages,which was defined by the World Health Organization as coronavirus disease 2019(COVID-19).The pandemic is considered a significant threat to global public health till *** this review,we have summarized the lessons learnt during the emergence and spread of SARS-CoV-2,including its prototype and *** overall clinical features of variants of concern(VOC),heterogeneity in the clinical manifestations,radiology and pathology of COVID-19 patients are also discussed,along with advances in therapeutic agents.

关键词： coronavirus disease 2019 SARS-CoV-2 epidemiology clinical features

Metallogenetic model of Jiaodong-type gold deposits,eastern China

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Science China Earth Sciences 2023年第10期66卷 2287-2310页

作者： Jun DENG Qingfei WANG Liang ZHANG Shengchao XUE xuefei liu Lin YANG Liqiang YANG Kunfeng QIU Yayun LIANG State Key Laboratory of Geological Process and Mineral Resources China University of GeosciencesBeijing100083China Frontiers Science Center for Deep-time Digital Earth China University of GeosciencesBeijing100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China

The genesis of giant gold provinces is an international scientific frontier,in which the source of a huge amount of gold and the drive for mineralization are key *** mineralization intensity of the Jiaodong gold province in eastern China is a rare occasion in the world,because it owns gold reserves of~5500 tons within an area of less than 10,000 km^(2).The Jiaodong gold province formed in the superimposed domain of diverse tectonic regimes in an intracontinental *** regional peak metamorphism and Triassic continental collision are followed by the tectonic transition and gold mineralization at ca.120 Ma with time intervals of 1.9 billion years and about 100 million years,*** Jiaodong gold deposits are different from orogenic and intrusion-related gold deposits in terms of the tectonic background,types of host rocks,and oreforming *** gold deposits show close spatial-temporal and genetic relationships to mafic igneous rocks,implying the derivation of ore-forming fluids from the metasomatic mantle *** dykes in Jiaodong have negativeε_(Hf)(t)values of-29.9 to-9.1,Os content of 0.002-0.16 ppb,heavyδ^(18)O up to 8.23‰,and high initial^(187)Os/^(188)Os ratios of *** indicate that the lithospheric mantle was metasomatized by ancient crust-derived *** lithospheric mantle in the western Jiaodong shows generally more enriched isotope features than that in the eastern part,which is explained to be an important reason for its huge gold *** mafic dykes show lighter Mg isotope characteristics(averageδ^(26)Mg of-0.33‰,n=50)and high Ca O content(overall greater than 6.5 wt%),indicating that the lithospheric mantle would also record the metasomatism by the carbonate rocks from the subducting oceanic *** the background of the rollback of the subducting paleo-Pacific slab and the destruction of the North China Craton,partial melting of the lower crust would produce granitic ma

关键词： Jiaodong-type gold deposits Mantle fluids Metasomatized lithospheric mantle Source of gold Tectonic regime transition

Development of Wheel-Legged Biped Robots:A Review

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Journal of Bionic Engineering 2024年第2期21卷 607-634页

作者： xuefei liu Yi Sun Shikun Wen Kai Cao Qian Qi Xiaoshu Zhang Huan Shen Guangming Chen Jiajun Xu Aihong Ji Lab of Locomotion Bioinspiration and Intelligent Robots College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and Astronautics29 Yudao StreetNanjing210016China State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China

The wheel-legged biped robot is a typical ground-based mobile robot that can combine the high velocity and high efficiency pertaining to wheeled motion and the strong,obstacle-crossing performance associated with legged *** robots have gradually exhibited satisfactory application potential in various harsh scenarios such as rubble rescue,military operations,and wilderness ***-legged biped robots are divided into four categories according to the open–close chain structure forms and operation task modes,and the latest technology research status is summarized in this *** hardware control system,control method,and application are analyzed,and the dynamic balance control for the two-wheel,biomimetic jumping control for the legs and whole-body control for integrating the wheels and legs are *** summary,it is observed that the current research exhibits problems,such as the insufficient application of novel materials and a rigid–flexible coupling design;the limited application of the advanced,intelligent control methods;the inadequate understanding of the bionic jumping mechanisms in robot legs;and the insufficient coordination ability of the multi-modal motion,which do not exhibit practical application for the wheel-legged biped ***,this study discusses the key research directions and development trends for the wheel-legged biped robots.

关键词： Wheel-legged biped robot Wheeled motion Legged motion Control strategy