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RF power coupling for the CSNS DTL

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Chinese Physics C 2011年第1期35卷 92-95页

作者：刘华昌彭军殷学军欧阳华甫傅世年 Accelerator center Institute of High Energy PhysicsCAS

The China Spallation Neutron Source （CSNS） drift tube linac （DTL） consists of four tanks and each tank is fed by a 2.5 MW klystron. Accurate predication of RF coupling between the RF cavity and ports is very important for DTL RF coupler design. An iris-type coupler is chosen to couple the RF power to the DTL accelerating cavity. The physical design of the DTL coupler and the calculations of RF coupling between the cavity and coupler are carried out. The results from the numerical simulations are in excellent agreement with the analytical results.

关键词： DTL RF coupler coupling coefficient

Microstructural characteristics and second-phase particles in yttrium-bearing Fe-10Ni-7Mn martensitic steels

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Journal of Rare Earths 2014年第4期32卷 326-333页

作者： F.Forghani M.Nili-Ahmadabadi School of Metallurgy and materials Engineering College of EngineeringUniversity of Tehran center of Excellence for high Performance materials University of Tehran

In this study, the microstructure and second-phase particles in yttrium （0.05 wt.%and 0.8 wt.%） bearing Fe-10Ni-7Mn steels were characterized. The results of X-ray analysis as well as scanning electron microscopy coupled with energy dispersive X-ray spectroscopy indicated the formation of （Fe, Ni, Mn）17Y2 precipitates with hexagonal structure in a Fe-10Ni-7Mn-0.8Y （wt.%） alloy. Lattice parameters of these precipitates were calculated as follows：a=0.8485 nm and c=0.8274 nm. Formation of Y2O3 sub-micron particles was also confirmed in both yttrium bearing steels via electrolytic phase extraction method. The effect of these precipitates on the prior austenite grain size was investigated. The results revealed that these precipitates had an effective role in controlling the prior austenite grain size.

关键词： Fe-10Ni-7Mn (wt.%) steel yttrium addition microstructure characterization second-phase particles grain growth rare earths

Thermal-Economic Comparative Analysis and Optimization of the Maisotsenko Gas Turbine Cycle under Different Configurations

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Journal of Thermal Science 2024年第6期33卷 2151-2165页

作者： SHI Qile HE Weifeng YAO Zhaohui GAO Yanfei SU Pengfei HAN Dong Advanced energy Conservation Research Group College of Energy and Power EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China Collaborative Innovation center for Advanced Aero-Engine Beijing 100191China State Key Laboratory of Long-Life high temperature materials Dongfang Electric Corporation Dongfang Turbine Co.LTDDeyang 618000China

The widespread adoption of Maisotsenko gas turbine cycle(MGTC)is significantly constrained by the design and manufacturing complexity of the *** proposition of innovative approaches to regulate the water carrying capacity and operational environment of the saturator,coupled with the performance and economic evaluation of systems under various configurations,can substantially facilitate its commercial *** the conventional two-stage MGTC system that solely comprises aftercooling and regenerative processes,this study proposes a three-stage MGTC system with an intercooling process(IMGTC),which considers the reuse of cooling water and energy *** pricing allocation and energy depreciation characteristics of components are analyzed,and the impact of key variables is ***,economic optimization of the system is conducted using ISIGHT to identify the optimal parameter combination and *** results indicate that the saturator price of IMGTC is lower and its exergy efficiency is higher than that of *** average water capacity of the IMGTC saturator is only 57.4%of that of the MGTC saturator,but the average exergy efficiency of IMGTC is 1.1%higher than that of ***,external parameters all lead to the levelized cost of electricity(LCOE).Thermo-economic optimization shows that the optimal LCOE of IMGTC is 0.26%lower than that of *** study confirms the feasibility of IMGTC,as well as its thermodynamic and economic advantages over MGTC.

关键词： Maisotsenko gas turbine cycle intercooling exergy efficiency levelized cost of electri thermo-economicoptimization

The Electrochemical Tuning of Transition Metal-Based materials for Electrocatalysis

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Electrochemical energy Reviews 2021年第1期4卷 146-168页

作者： Fangming Liu Le Zhang Lei Wang Fangyi Cheng Key Laboratory of Advanced energy materials Chemistry(Ministry of Education) Engineering Research Center of High-Efficiency Energy Storage(Ministry of Education)Renewable Energy Conversion and Storage CenterCollege of ChemistryNankai UniversityTianjin 300071China

The development of clean and sustainable energy depends largely on electrocatalysis-driven *** of this,tremendous efforts have been devoted to the search for efficient electrocatalysts to reduce the overpotential and increase the selectivity of electrochemical *** the various approaches,electrochemical tuning is seen as a promising tech-nique to controllably tune the properties of catalytic materials under mild *** on this,this review will present representative electrochemical tuning methodologies involving insertion and conversion reactions in batteries as well as in situ electrode modulation during electrocatalysis *** review will first provide an introduction of electrochemi-cal tuning strategies from the perspective of reactions and ***,this review will present comprehensive discussions on recent advancements in the modulation of various electrocatalyst properties,including electronic structure,crystalline phase,lattice strain and dimensional size,all of which significantly impact corresponding intrinsic activity and active site *** review will also highlight the merits,challenges and issues of electrochemical tuning and propose promising directions in the exploration of corresponding methods in the design and enhancement of electrocatalysts for future energy applications.

关键词： Electrochemical tuning Electrocatalysts Hydrogen evolution Oxygen evolution Oxygen reduction Carbon dioxide reduction

Frist-principles prediction of elastic, electronic,and thermodynamic properties of high entropy carbide ceramic (TiZrNbTa)C

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Rare Metals 2022年第3期41卷 1002-1014页

作者： Kai Xiong Bao-Wen Wang Ze-Peng Sun Wei Li Cheng-Chen Jin Shun-Meng Zhang Si-Yong Xu Lei Guo Yong Mao National center for International Research on Photoelectric and energy materials School of Materials and EnergyMaterials Genome InstituteYunnan UniversityKunming 650091China Advanced Computing center Information Technology CenterYunnan UniversityKunming 650091China

high-entropy carbide ceramics (HECs) have drawn increasing attention as their excellent mechanical and thermal properties. In this work, the crystal stability,mechanical behavior, electronic and thermodynamic properties of (TiZrNbTa)C HEC are investigated by the first-principles calculations. Obtained results reveal that the disordered transition-metal (TM) atoms result in serious local lattice distortion within the crystal. The lattice distortion plays a key role for the structural stabilization,mechanical anisotropy and thermodynamic behaviors of(TiZrNbTa)C. Increasing pressure leads to decrease the lattice parameter, volume and brittleness, meanwhile increase the elastic constants, elastic moduli, mechanical anisotropy, sound velocity, and Debye temperature. It is also discovered that charge delocalization occurs with the increase in pressure. The mechanical stability and anisotropy of (TiZrNbTa)C are attributed primarily to TM-C bonding.

关键词： high-entropy carbide ceramics Elastic constants Anisotropy Thermodynamic First-principles

Thermal analysis for the high duty cycle PIMS accelerator

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Chinese Physics C 2010年第7期34卷 1005-1008页

作者：刘华昌彭军阮玉芳傅世年 Accelerator center Institute of High Energy PhysicsCAS

To develop the high power proton linear accelerator for the Accelerator Driven System（ADS） program,the preliminary design of the Pi mode accelerating structure（PIMS） has been carried *** is estimated that PIMS would heat up to 80 for low duty cycle（0.1%） without water-cooling,which is not acceptable thus water-cooling is *** structure stability for the high duty cycle or even for CW operation is crucially important for the ADS ***,thermal analysis with water-cooling for a high duty accelerator in our ADS research is performed to control the frequency shift caused by a temperature rise.

关键词： PIMS high duty cycle thermal analysis water-cooling

Complex Precipitation Sequences of Al-Cu-Li-(Mg)Alloys Characterized in Relation to Thermal Ageing Processes

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Acta Metallurgica Sinica(English Letters) 2016年第1期29卷 94-103页

作者： Zhen Gao Jiang-Hua Chen Shi-Yun Duan Xiu-Bo Yang Cui-Lan Wu center for high-Resolution Electron Microscopy College of Materials Science and EngineeringHunan University

The A1-Cu-Li-（Mg） alloy is a high-performance lightweight material strengthened by complex coexisting precipitates that form in the alloy upon thermal ageing. Using high-resolution （scanning） transmission electron microscopy in association with first-principles energy calculations, we systematically studied the complex coexisting precipitates in the alloys and correlated their precipitation sequences with thermal ageing processes applied. The principal results are the following：（1） eight types of precipitates can be observed in the alloy; （2） of these precipitates, the Tl-phase is most stable. The S-phase precipitates with segregated Li atoms at their interfacial edges are unexpectedly more stable than the a-phase; （3） the Tl-phase has a characteristic precursor that plays the key role in its nucleation and growth.

关键词： AI-Cu-Li alloy Electron microscopy Ageing Precipitation Strength

Effect of carbon addition on microstructure and mechanical properties of a typical hard-to-deform Ni-base superalloy

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Progress in Natural Science:materials International 2023年第2期33卷 232-243页

作者： Lei Jia Heng Cui Shufeng Yang Shaomin Lv Xingfei Xie Jinglong Qu Collaborative Innovation center of Steel Technology University of Science and Technology Beijing State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing GAONA materials & Technology Co. Ltd. high-temperature materials Institute Central Iron and Steel Research Institute

In this paper, the as-cast microstructure, microsegregation, and mechanical properties of GH4151 superalloys with a carbon addition were studied by scanner electron microscopy(SEM), transmission electron microscope(TEM), electron probe microanalysis(EPMA), differential thermal analyzer(DSC), and electron backscattered diffraction(EBSD). The results show that the solid solution effect of carbon in alloys is limited, the addition of C from 0.01 to 0.08 wt% significantly refines the secondary dendrite spacing(SDAS) from 61.7 to 57.4 and 51.8 μ*** to the influence of thermal solutal convection, the most severe segregation is found in the C-0.04 alloy, and the solidification ranges of C-0.01, C-0.04, and C-0.08 alloys are 87°C, 96°C, and 83°C, respectively. Owing to the reduced solidification pores and formed finely dispersed carbides, C-0.04 shows excellent ultimate tensile strength(442 MPa) and superior total elongation(1.368%) at 1100°C much better than that of C-0.01(130.7MPa, 0.085%) and C-0.08(248 MPa, 1.026%).

关键词： GH4151 superalloys Carbon Microstructure and microsegregation Mechanical properties

Application of materials based on group VB elements in sodium-ion batteries:A review

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Journal of materials Science & Technology 2018年第11期34卷 1969-1976页

作者： Menglei Sun Yu Jiang Jiangfeng Ni Liang Li College of Physics Optoelectronics and EnergyCenter for Energy Conversion Materials & Physics (CECMP)Soochow University

Owing to their high redox activity, abundant resource, and low cost, compounds based on group VB elements（V, Nb, and Ta） are promising electrode materials for an array of energy storage devices. Moreover,their open structure benefits transportation and accommodation of alkali Na＋ions, rending them particularly appealing for cost-effective sodium-ion batteries（SIBs）. In the last decade, these materials have evoked intensive investigations in SIBs, serving as either cathode, anode, or both depending on their sodiation degree and redox potential. Exciting progress has been made, but significant gaps in our knowledge still remain. Their practical application in SIBs remains unclear and thus calls for further efforts to settle several technical challenges in terms of poor conductivity, unstable cycling, and inefficient charge storage. In this perspective, a brief overview is given of recent progress on how to solve these technical issues and envision their bright future in SIBs, which may serve as a source to inspire researches on relevant topics.

关键词： Vanadium Niobium Tantalum energy storage Sodium-ion battery