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An Improved Synthesis of trans-3,3b,4,9b,10,11-Hexahydro -6-methoxy-9b-methyl-7- (1-methylethyl) phenanthro {1,2-c[furan-1,5-dione]}

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Chinese Chemical Letters 2001年第7期12卷 579-580页

作者： Xue Qiang YIN Guang Zhong YANG yuan chao li Shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai 200031

trans-3, 3b, 4, 9b, 10, 11-Hexahydro-6-methoxy-9b-methyl-7-(1-methylethyl) phenanthro {1,2-c[furan-1,5-dione]} was synthesized with good yield in two steps from triptophenolide methyl ether under mild conditions.

关键词： Tripterygium wilfordii triptolide triptophenolide methyl ether

Interface structure of α-Mg/14H-LPSO:First-principles prediction and experimental study

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Journal of Rare Earths 2024年第9期42卷 1792-1799,I0006页

作者： yuan Shi Xiaohua Zhang Hongyan Yue chao li School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin150040China

The interfacial structure of the α-Mg/14H-LPSO phase in rare earth-including magnesium alloy was investigated via high-angle annular dark-field scanning transmission electron microscopy(HAADFSTEM) imaging and first-principles calculations of density-functional *** possible interfacial models were constructed according to the different terminations of the LPSO phase,and the corresponding interfacial energies were calculated,from which the four most stable structures(Terl-MgY-hollow,Ter2-Zn-hollow,Ter3-MgYII-hollow and Ter4-Mg-bridge) were *** interfacial phase diagrams related to the Y chemical potentials were obtained from the calculations,and the most stable interfacial structure was ***-MgY-hollow and Ter2-Zn-hollow have the lowest interfacial energies in the range of-0.7 eV <Δμγ<-0.6 eV,where fluctuating change of state is the minimized and the interface is the most *** separation work of the two models was calculated to predict the bonding strength of the structures at both ends of the *** calculation results show that the maximum interfacial separation work is 1.45 J/m^(2) for the interface model of α-Mg and 14H-LPSO phase structure with Ter2-Zn-hollow termination.

关键词： Rare earths Magnesium alloy HAADF-STEM LPSO First-principles Interface

Thermofluidic investigations of oil natural transformer:Closed-loop modelling and experimental validation

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High Voltage 2024年第1期9卷 230-240页

作者： yuan li Yiran Gao Chen Wang chao Zhu Ying li yuankai Wang Guanjun Zhang State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anChina Electric Power Research Institute of State Grid Shaanxi Electric Power Co. Ltd.Xi'anChina TBEA Hengyang Transformer Co. Ltd.HengyangChina

Excessively high temperatures inside a power transformer can accelerate the ageing rate and even cause unplanned *** estimating the hot-spot temperature(HST)of a power transformer is important for regulating the load and ensuring long-term *** this study,a closed-loop model of a 110-kV product transformer with an oil natural/air forced(ONAF)cooling mode is built to predict HST,in which the compression ratio of windings,equivalent heat source and radiator geometry are *** to the flow field of the winding,the‘dead oil zone’and reverse oil flow are observed in the horizontal oil *** accuracy of the proposed model is experimentally validated by temperature-rise *** results show that the absolute errors between the measured results and simulation are below 5°C,and the average error is~2°***,the arrangements of windings and radiators are studied to enhance the oil *** adding 5 washers to the high-voltage winding,the average temperature can be decreased by 6°C compared with the case without a *** the radiator can also mitigate the characteristic temperatures,and the optimal height difference between the radiator and winding centre is suggested to be 0.66 m.

关键词： winding arrangement adding

Thioacetamide Additive Homogenizing Zn Deposition Revealed by In Situ Digital Holography for Advanced Zn Ion Batteries

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Nano-Micro Letters 2024年第6期16卷 261-275页

作者： Kaixin Ren Min li Qinghong Wang Baohua liu Chuang Sun Boyu yuan chao Lai lifang Jiao chao Wang School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhou 221116JiangsuPeople’s Republic of China Jiangsu Key Laboratory of Advanced Laser Materials and Devices School ofPhysics and Electronic EngineeringJiangsu Normal UniversityXuzhou 221116JiangsuPeople’s Republic of China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai University300071 TianjinPeople’s Republic of China

Zinc ion batteries are considered as potential energy storage devices due to their advantages of low-cost,high-safety,and high theoretical ***,dendrite growth and chemical corrosion occurring on Zn anode limit their *** problems can be tackled through the optimization of the ***,the screening of electrolyte additives using normal electrochemical methods is time-consuming and ***,a fast and simple method based on the digital holography is *** can realize the in situ monitoring of electrode/electrolyte interface and provide direct information concerning ion concentration evolution of the diffusion *** is effective and time-saving in estimating the homogeneity of the deposition layer and predicting the tendency of dendrite growth,thus able to value the applicability of electrolyte *** feasibility of this method is further validated by the forecast and evaluation of thioacetamide *** on systematic characterization,it is proved that the introduction of thioacetamide can not only regulate the interficial ion flux to induce dendrite-free Zn deposition,but also construct adsorption molecule layers to inhibit side reactions of Zn *** easy to operate,capable of in situ observation,and able to endure harsh conditions,digital holography method will be a promising approach for the interfacial investigation of other battery systems.

关键词： Digital holographic microscopy In situ observation Electrode/electrolyte interface Zn dendrites Screening electrolyte additives

The origin and evolution of Earth's nitrogen

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National Science Review 2024年第06期11卷 56-75页

作者： yuan li State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences Bayerisches Geoinstitut Universit?t Bayreuth

Nitrogen is a vital element for life on Earth. Its cycling between the surface(atmosphere + crust) and the mantle has a profound influence on the atmosphere and climate. However, our understanding of the origin and evolution of Earth's nitrogen is still incomplete. This review presents an overview of the current understanding of Earth's nitrogen budget and the isotope composition of different reservoirs, laboratory constraints on deep nitrogen geochemistry, and our understanding of the origin of Earth's nitrogen and the deep nitrogen cycle through plate subduction and volcanism. The Earth may have acquired its nitrogen heterogeneously during the main accretion phase, initially from reduced, enstatite-chondrite-like impactors,and subsequently from increasingly oxidized impactors and minimal CI-chondrite-like materials. like Earth's surface, the mantle and core are also significant nitrogen reservoirs. The nitrogen abundance and isotope composition of these three reservoirs may have been fundamentally established during the main accretion phase and have been insignificantly modified afterwards by the deep nitrogen cycle, although there is a net nitrogen ingassing into Earth's mantle in modern subduction zones. However, it is estimated that the early atmosphere of Earth may have contained ～1.4 times the present-day atmospheric nitrogen(PAN),with ～0.4 PAN being sequestered into the crust via biotic nitrogen fixation. In order to gain a better understanding of the origin and evolution of Earth's nitrogen, directions for future research are suggested.

关键词： nitrogen isotopes silicate Earth atmosphere magma ocean

Enhanced Electrical Properties of Styrene-grafted Polypropylene Insulation for Bulk Power Transmission HVDC Cables

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 361-370页

作者： Hao yuan Shixun Hu Yao Zhou chao yuan Wenbo Song Qing Shao Hongwei Shi Juan li Jun Hu Qi li Jinliang He SINOPEC Beijing Research Institute of Chemical Industry Beijing 100013China State Key Laboratory of Power Systems Department of Electrical EngineeringTsinghua UniversityBeijing 100084China

Polypropylene(PP)is considered to be a rather promising material for HVDC cable *** modification has proved to be an effective method on the electrical property improvements of *** paper reports on the highlyenhanced electrical properties of styrene-grafted polypropylene(PP-g-St)and their related *** influence of grafting styrene on crystallization structures,thermal properties and electrical properties of PP-g-St are characterized and *** results show that PP-g-St exhibits remarkably enhanced DC volume resistivity,suppressed space charge accumulation and improved DC breakdown strengths as compared to *** observation shows PP-g-St has small,imperfect spherulites with indistinct boundaries,which is strongly correlated to enhanced electrical *** study provides an effective grafting strategy to design high-performance HVDC cable insulation materials for bulk power transmission systems.

关键词： Electrical properties grafting modification polypropylene styrene

Interfaces engineering of heterostructured Ni Co P/Ni Fe LDH@CC for attaining high catalytic activity in long-lasting rechargeable Zn–air batteries

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Rare Metals 2024年第10期43卷 4961-4972页

作者： Xiao-lin Hu Ji-Chuan Fan Xiang li Zhen-Kun Wu yuan-Yi li chao-He Xu School of Science Chongqing Key Laboratory of New Energy Storage Materials and DevicesChongqing University of Technology JINSHAN Science&Technology (Group) Co. Ltd. National Engineering Research Center for Magnesium Alloys Chongqing University College of Aerospace Engineering Chongqing University

Zinc-air batteries (ZABs) offer tremendous potential in various industries and daily life due to their excellent energy density,safety and ***,the practical application of ZABs has been severely hindered by challenges such as high low round-trip efficiencies and overpotential,primarily attributed to the inherent sluggish kinetics in the oxygen evolution reaction(OER) of air *** address these issues effectively and economically,heterojunction engineering accompanied by interfacial chemistry emerges as an ideal approach to designing efficient OER ***,a novel heterogeneous interfacial chemical structure,namely NiCoP/NiFe LDH (layered double hydroxide),needle-like NiCoP and NiFe LDH nanosheets were assembled from cores and shells,***,the NiCoP/NiFe LDH-based ZABs have an exceptionally long cycle life of 238 h,far superior to Pt/C+Ir/C batteries (～97 h).Theoretical calculations and experimental results demonstrate that NiCoP/NiFe LDH possesses tunable interfacial chemistry,demonstrating significant electronic,coordination,geometric and synergistic *** enhancements dramatically improve the active site density,intrinsic activity and electrochemical durability of the *** summary,this work provides a solid foundation for the development of costeffective OER electrocatalysts for electrochemical energy devices.

关键词： Coupling effects Interface catalysis Oxygen evolution reaction Theoretical simulation Zinc–air batteries

Recyclable Polypropylene-based Insulation Materials for HVDC Cables:Progress and Perspective

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 2208-2220页

作者： Yao Zhou Shixun Hu chao yuan Jun Hu Qi li Jinliang He State Key Laboratory of Power Systems Department of Electrical EngineeringTsinghua UniversityBeijing 100084China Beijing Key Lab of High Voltage&EMC and State Key Lab of Alternate Electrical Power System with Renewable Energy SourcesNorth China Electric Power UniversityBeijing 102206China.

Polypropylene(PP)-based recyclable materials have attracted tremendous interest for HVDC cable insulation applications due to their superior electrical properties,e.g.,high thermal stability and superior *** with crosslinked polyethylene(XLPE),PP-based materials exhibit the advantages of not only higher working temperatures but also facile and efficient cable manufacturing with reduced costs,which are highly desirable in HVDC cable *** their promising advantages,PP-based materials have received significant attention from both academia and industry in the field of HVDC cable *** order to adopt PP as a cable insulation material,the mechanical flexibility of PP should be ***,regulations of the mechanical properties inevitably influences the electrical properties of *** extensive research has been conducted on the regulation of the mechanical and electrical properties of *** review summarizes the research progress on recyclable PP-based materials for HVDC cable insulation *** attention is placed on the electrical property regulations and material structure-property *** challenges that remain to be addressed and the opportunities for future studies on PP-based recyclable HVDC cable insulation materials are also presented.

关键词： polypropylene HVDC cable dielectric materials recyclable insulation materials

Robustness of the octupole collectivity in 144Ba within the cranking covariant density functional theory in 3D lattice

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Nuclear Science and Techniques 2024年第8期35卷 124-131页

作者： Ze‑Kai li yuan‑yuan Wang Mathematics and Physics Department North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding 071000China

The octupole deformation and collectivity in octupole double-magic nucleus 144Ba are investigated using the Cranking covariant density functional theory in a three-dimensional lattice *** reduced B(E3)transition probability is implemented for the first time in semiclassical approximation based on the microscopically calculated electric octupole *** available data,including the I-ωrelation and electric transitional probabilities B(E2)and B(E3)are well ***,it is shown that the ground state of 144Ba exhibits axial octupole and quadrupole deformations that persist up to high spins(I≈24h).

关键词： Octupole collectivity Cranking covariant density functional theory Rotational spectrum Electric transitional probabilities