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High-energy-density lithium manganese iron phosphate for lithium-ion batteries: Progresses, challenges, and prospects

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Journal of Energy Chemistry 2025年第1期100卷 1-17页

作者： Bokun Zhang Xiaoyun Wang Shuai Wang Yan Li Libo Chen Handong jiao Zhijing Yu Jiguo Tu State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Research Institute for Intelligent Wearable Systems The Hong Kong Polytechnic University Institute of Advanced Structure Technology Beijing Institute of Technology

The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion *** manganese iron phosphate (LiMnxFe1-xPO4) has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy *** LiMnxFe1-xPO4has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and Li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap *** review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of LiMnxFe1-xPO4to analyze reaction processes accurately and guide material ***,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of LiMnxFe1-xPO4,including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology ***,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are *** importantly,it is expected to provide key insights into the development of high-performance and stable LiMnxFe1-xPO4materials,to achieve practical energy storage requirements.

关键词： Lithium manganese iron phosphate High energy density Lithium-ion batteries Reaction mechanism Tap density

Imperative for long-term management and surveillance in Kawasaki disease

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World Journal of Clinical Cases 2025年第4期13卷 61-63页

作者： Yan Pan Fu-Yong jiao Department of Pediatrics The First Affiliated Hospital of Yangtze UniversityJingzhou 434000Hubei ProvinceChina Shaanxi Kawasaki Disease Diagnosis and Treatment Center Children’s HospitalShaanxi Provincial People’s Hospital of Xi’an Jiaotong UniversityXi’an 710000Shaanxi ProvinceChina

Kawasaki disease(KD)is a significant pediatric vasculitis known for its potential to cause severe coronary artery *** the effectiveness of initial treatments,such as intravenous immunoglobulin,KD patients can experience long-term cardiovascular issues,as evidenced by a recent case report of an adult who suffered a ST-segment elevation myocardial infarction due to previous KD in the World Journal of Clinical *** editorial emphasizes the critical need for long-term management and regular surveillance to prevent such *** drawing on recent research and case studies,we advocate for a structured approach to follow-up care that includes routine cardiac evaluations and preventive measures.

关键词： Kawasaki disease long-term management Coronary artery aneurysm Surveillance Preventive care

Axial coordination regulation of MOF-based single-atom Ni catalysts by halogen atoms for enhanced CO_(2) electroreduction

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Nano Research 2022年第12期15卷 10063-10069页

作者： Jia-Xin Peng Weijie Yang Zhenhe Jia long jiao Hai-long Jiang Department of Chemistry University of Science and Technology of ChinaHefei230026China Department of Power Engineering School of EnergyPower and Mechanical EngineeringNorth China Electric Power UniversityBaoding071003China

Single-atom catalysts(SACs),with the utmost atom utilization,have attracted extensive interests for various catalytic *** coordination environment of SACs has been recognized to play a vital role in catalysis while their precise regulation at atomic level remains an immense ***,a post metal halide modification(PMHM)strategy has been developed to construct Ni-N4 sites with axially coordinated halogen atoms,named Ni1-N-C(X)(X=CI,Br,and I),on pre-synthetic nitrogen-doped carbon derived from metal-organic *** axial halogen atoms with distinct electronegativity can break the symmetric charge distribution of planar Ni-N4 sites and regulate the electronic states of central Ni atoms in Ni1-N-C(X)(X=Cl,Br,and I).Significantly,the Ni1-N-C(CI)catalyst,decorated with the most electronegative Cl atoms,exhibits Faradaic efficiency of CO up to 94.7%in electrocatalytic CO_(2) reduction,outperforming Ni1-N-C(Br)and Ni1-N-C(I)***,Ni1-N-C(CI)also presents superb performance in Zn-CO_(2) battery with ultrahigh CO selectivity and great *** calculations reveal that the axially coordinated Cl atom remarkably facilitates*COOH intermediate formation on single-atom Ni sites,thereby boosting the CO_(2) reduction performance of Ni1-N-C(CI).This work offers a facile strategy to tailor the axial coordination environments of SACs at atomic level and manifests the crucial role of axial coordination microenvironments in catalysis.

关键词： metal-organic frameworks single-atom catalysts CO_(2)electroreduction axial coordination environment

Adaptive Observer Based Backstepping Controller Design for Dynamic Ship Positioning

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China Ocean Engineering 2017年第5期31卷 639-645页

作者： DENG Fang WANG long-jin jiao Dong-mei College of Mechanical & Electrical Engineering Qingdao University of Science & Technology

Modified adaptive observer based backstepping control system for dynamic positioning of ship is proposed. As an improvement, the adaptive observer takes the first-order wave frequency model and the bias term which represent the slowly varying environmental disturbances and the unmodeled dynamics. Thus, the wave-frequency motions are filtered out, and only the reconstructed low-frequency motions are sent as inputs of the controller. Furthermore, as the ship dynamics parameters are unknown, the adaptive estimation law is designed for both the unknown ship dynamics and the unmeasured state variables. Based on the estimated states and parameters, backstepping controller considering the integral action is designed. Global exponential stability （GES） for the total system is proved using Lyapunov direct method. Simulation results show a good performance of the observer and control system.

关键词： Dynamic positioning backstepping control adaptive observer parameter estimation

An introduction to the novel vacuum plume effects experimental system

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Science China(Technological Sciences) 2016年第6期59卷 953-960页

作者： CAI Guo Biao LING Gui long HE Bi jiao School of Astronautics Beihang University

This paper introduces a newly developed vacuum Plume effects Experimental System(PES) used for plume effect tests of rocket engines and vacuum heat tests of satellites. The design level, manufacturing technique, and testing capabilities of the PES have reached a highly advanced level at home and abroad. The PES mainly consists of a vacuum chamber, vacuum acquisition system, nitrogen system, helium system, and parameter measurement system. A breakthrough was obtained on the Large Scale Cryo-Pumping System, which was based on a combined liquid nitrogen and liquid helium heat sink. An internal cryopump with a limiting temperature of 4.2 K and an efficient absorption area of 305 m2 was developed. The absorption capability of the cryopump was above 7×107 L/s. Vacuum plume tests were performed in the temperature ranges of ambient temperature, liquid nitrogen, and liquid helium. The experimental results showed that the plume test capability of PES is higher than that of similar foreign equipment STG and CHAFF-4. For 2 g/s and 117 N rocket engines, the dynamic vacuum degree of environment was 8.0×10?4 Pa(approximately 137 km height) and 1.1×10?2 Pa(approximately 106 km height), respectively.

关键词： vacuum plume effect liquid nitrogen heat sink liquid helium heat sink plume absorption pump

Promotion Mechanism of H2O for Stereoselectivity in Pd(Ⅱ)-catalyzed C—H Aryiation of Diarylphosphinamides with Arylboronic Acids

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Chemical Research in Chinese Universities 2020年第5期36卷 843-846页

作者： CAI Yanchun jiao long QIU Xuepcng DU Zhijun Polymer Composites Engineering laboratory Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China

On the basis of a series of control experiments and nuclear magnetic resonance analyses,it is discovered that Boc-protected amino acid ligand coordinated to Pd center is partly replaced by N,N-dimethylformamide,and H2O can inhibit coordination of N,N-dimethylformamide to Pd *** novel action mechanism perfectly explains H2O promotion for stereoselectivity in Pd(II)-catalyzed C—H aryiation of diarylphosphinamides with arylboronic acids.

关键词： C-H activation Stereoselectivity Water Ligand exchange

An improved three-dimensional spherical DDA model for simulating rock failure

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Science China(Technological Sciences) 2015年第9期58卷 1533-1541页

作者： jiao YuYong HUANG GangHai ZHAO ZhiYe ZHENG Fei WANG long State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences School of Civil and Environmental Engineering Nanyang Technological University

In this paper, a discontinuous numerical model, namely SDDARF3D(three-dimensional spherical discontinuous deformation analysis for rock failure), is proposed for simulating the whole process of rock failure. Firstly, within the framework of the classical discontinuous deformation analysis(DDA) method, the formulation of three-dimensional spherical DDA(3D SDDA) is deduced; secondly, a bonding and cracking algorithm is constructed and the SDDARF3 D model is proposed; thirdly, corresponding VC++ calculation code is developed and some verification examples are calculated. The simulated results can intuitively reproduce the failure phenomena of rock mass, indicating that the proposed SDDARF3 D numerical model is correct and effective.

关键词： rock failure three-dimensional spherical discontinuous deformation analysis crack propagation bonding and cracking algorithm

Microstructure and properties of Al_3Zr/2024Al in situ composites after forging

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Rare Metals 2016年第12期35卷 920-925页

作者： Lei jiao Yu-Tao Zhao Jian-Chao Chen long Chen School of Materials Science and Engineering JiangsuUniversity

To research the influencing rule of severe plastic deformation on Al matrix in situ composites, 10wt%Al3Zr/2024Al in situ particle-reinforced composite was prepared by direct melt reaction （DMR）, and then, the composite was hot-forged by one direction with 90% plastic deformation. Then, the microstructure of the forging state composite was observed, and the change law of mechanical properties and friction performances after and before plastic deforming was compared. The results indicate that the Al3Zr-reinforced particle rotates and breaks into smaller size of 10-20μm with the matrix flow; in addition, these smaller particles distribute more orderly in orientation and dispersedly. The 2024 matrix grain changes from as-cast tissue to fibrous tissue with length of 100 μm along the forging direction. Some mechanical properties of composites hot-forged by one direction with 90 % plastic deformation are improved much obviously. For example, the tensile strength is improved by 39.75 %, reaching 225 MPa, and the hardness is improved by 35.84 %, reaching HBW 76.83. Besides, the wear rate reduces, wear depth and area decline, and the wear-resisting property is improved after hot forging.

关键词： Al3Zr/2024Al in situ composites Forging Microstructure Mechanical properties Wear-resisting property

Mineralogical characterization of airborne individual particulates in Beijing PM10

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Journal of Environmental Sciences 2006年第1期18卷 90-95页

作者： LU Sen-lin SHAO long-yi WU Ming-hong jiao Zheng Shanghai Applied Radiation Institute School of Environmental and Chemical Engineering Shanghai University Shanghai 201800 China Department of Earth Science China University of Mining and Technology Beijing 100083 China

This work mainly focuses on the mineralogical study of particulate matter（PM10） in Beijing. Samples were collected on polycarbonate filter from April, 2002 to March, 2003 in Beijing urban area. Scanning electronic microscopy coupled with energy dispersive X-ray（SEM/EDX） was used to investigate individual mineral particles in Beijing PM10. 1454 individual mineral particulates from 48 samples were analysed by SEM/EDX. The results revealed that mineral particulates were complex and heterogeneous. 38 kinds of minerals in PM10 were identified. The clay minerals, of annual average percentage of 30.1%, were the main composition among the identified minerals, and illite/smectite was the main composition in clay minerals, reaching up to 35%. Annual average percentage of quartz, calcite, compound particulates, carbonates were 13.5%, 10.9%, 11.95%, 10.31%, respectively. Annual average percentage less than 10% were gypsum, feldspar, dolomite, and so on. Fluorite, apatite, halite, barite and chloridize zinc（ZnCl2） were firstly identified in Beijing PM10. Sulfurization was found on surface of mineral particles, suggested extensive atmospheric reaction in air during summer.

关键词： inhalable particulate matter(PM10) individual analysis mineral composition