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Construction of Ni–Al–Ru EAM potential and application in misfit dislocation system

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Progress in Natural Science:Materials International 2020年第4期30卷 539-544页

作者： Enlai Yue Tao Yu chongyu Wang Junping Du Central Iron and Steel Research Institute Department of Physics Tsinghua University Department of Mechanical Science and Bioengineering Osaka University

In Ni-based single crystal superalloys, ruthenium is sometimes introduced as one of the creep resistances through retarding the thermally-activated deformation processes, such as dislocation glide and climb. In the present study, an embedded-atom-method potential of Ni–Al–Ru system was constructed. Using the present potential,the effect of Ru on the lattice misfit between γ(Ni) and γ′(Ni3Al) phases was investigated. The results show that Ru doping decreases the lattice misfit, which is consistent with the calculations from first-principles. The interaction between Ru and misfit dislocation was also studied. The results of interaction energy between Ru and misfit dislocation, and the simulations of misfit dislocation motion in the Ru-doping system by molecular dynamics method both show that Ru possesses the pinning effect on the misfit dislocation. These results can provide useful help for further insights of the role of Ru in the alloys.

关键词： Embedded-atom-method potential Ruthenium Ni–Al–Ru Misfit dislocation

Hot Deformation Behaviour of SiC/AA6061 Composites Prepared by Spark Plasma Sintering

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Journal of Materials Science & Technology 2016年第4期32卷 291-297页

作者： Xiaopu Li chongyu Liu Kun Luo Mingzhen Ma Riping Liu State Key Laboratory of Metastable Materials Science and Technology Yanshan University Key Laboratory of New Processing Technology for Nonferrous Metal & Materials Ministry of Education Guilin University of Technology Guangxi Key Laboratory of Universities for Clean Metallurgy and Comprehensive Utilization of Nonferrous Metal Resources Guilin University of Technology

In this study, SiC/AA6061 composites with different SiC volume fractions （5%, 10%, 15% and 20%） were fabricated by spark plasma sintering. The deformation behaviour of the composites was studied by uni- axial compression test at temperatures from 573 K to 773 K and strain rates between 0.001 s^-1 and 1 s^-1. Results indicate that the flow stress of SiCIAA6061 composites increases with the increase of SiC volume fraction, with the decrease of deformation temperature and with the decrease of strain rate. The main deformation mechanism of the composites is dynamic recrystallisation （DRX）, and the DRX degree depends on the processing parameters of deformation. Higher SiC volume fraction, higher deformation temper- ature and lower deformation strain rate promote the occurrence of DRX. The strain rate sensitivity and deformation activation energy of SiC/AA6061 composites are calculated. Results show that with the in- crease in deformation temperature and the decrease in SiC volume fraction, the strain rate sensitivity of the composites increases. From 573 K to 773 K, the average deformation activation energy of 5vol.%SiC/ AA6061, 10voI.%SiC/AA6061, 15voI.%SiC/AA6061 and 20vol.%SiC/AA6061 are 20Z91, 230.88, 237.7 and 249.87 kJ mol^-1, respectively. The optimum hot working zone of the SiC/AA6061 composites is in the tem- perature range of 723 K to 773 K at strain rates from 0.1 s^-1 to 1 s^-1.

关键词： Spark plasma sinteringHot deformationAI alloy matrix composites

Evaluating Functions of Reservoirs'Storage Capacities and Locations on Daily Peak Attenuation for Ganjiang River Basin Using Xinanjiang Model

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Chinese Geographical Science 2016年第6期26卷 789-802页

作者： DU Jinkang ZHENG Dapeng XU Youpeng HU Shunfu XU chongyu School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210093China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China Anhui Electric Power Design Institute of China Energy and Electricity Construction Group Hefei 230601China Department of Geography Southern Illinois University EdwardsvilleEdwardsville IL 62026USA State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Department of Geosciences University of OsloN-0316 Oslo 1047 BlindernNorway

Flooding is the most prevalent and costly natural disaster in the world and building reservoirs is one of the major structural measures for flood control and management. In this paper, a framework was proposed to evaluate functions of reservoirs′ locations and magnitudes on daily peak flow attenuation for a large basin of China, namely Ganjiang River Basin. In this study, the Xinanjiang model was adopted to simulate inflows of the reservoirs and flood hydrographs of all sub-catchments of the basin, and simple reservoir operation rules were established for calculating outflows of the reservoirs. Four reservoirs scenarios were established to analyze reservoirs′ locations on daily peak flow attenuation. The results showed that: 1) reservoirs attenuated the peak discharges for all simulated floods, when the flood storage capacities increase as new reservoirs were built, the peak discharge attenuation by reservoirs showed an increasing tendency both in absolute and relative measures; 2) reservoirs attenuated more peak discharge relatively for small floods than for large ones; 3) reservoirs reduced the peak discharge more efficiently for the floods with single peak or multi peaks with main peak occurred first; and 4) effect of upstream reservoirs on peak attenuation decreased from upper reaches to lower reaches; upstream and midstream reservoirs played important roles in decreasing peak discharge both at middle and lower reaches, and downstream reservoirs had less effect on large peak discharge attenuation at outlet of the basin. The proposed framework of evaluating functions of multiple reservoirs′ storage capacities and locations on peak attenuation is valuable for flood control planning and management at basin scale.

关键词： reservoir peak flow Xinanjiang model reservoir operation Ganjiang River Basin

Structure of Graphene, and Mechanical and Bonding Characteristics of Single Wall Carbon Nanotube by Linear Scaling Quantum Mechanical Method

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Journal of Materials Science & Technology 2010年第7期26卷 614-618页

作者： Jun Cai Guiqin Li chongyu Wang Zhiyong Xie School of Nuclear-Science & Engineering North China Electric Power University Beijing 102206 China Department of Physics Tsinghua University Beijing 100084 China Department of Materials Science & Engineering North China Electric Power University Beijing 102206 China

Using a linear scaling self-consistent-charge density functional tight binding （SCC-DFTB） and an ab initio Omol method, the bonding characteristics and Young＇s modulus of （10, 0） and （10,10） single-walled carbon nanotubes are calculated. The structure of a graphene is also calculated. It is found that the C-C and C-H bond length, their distribution characteristics on the tube, and Young^s modulus of the tube by linear scaling SCC-DFTB are identical to those by ab initio, while the computing cost by the linear scaling SCC-DFTB is reduced by more than 30 times as compared with that by the Dmol for the （10,0） and （10,10） tubes. By computing the structure of a graphene it is also found that the linear scaling SCCDFTB is reliable and time-saving.

关键词： Single walled nanotube tube Young's modulus Linear scaling method Density functional tight-binding

Biomarker evidence for the Late Neoproterozoic deep-water oxygenation

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Biomarker evidence for the Late Neoproterozoic deep-water ox...

Spin and spin-orbit coupling effects in nickel-based superalloys:A first-principles study on Ni_(3)Al doped with Ta/W/Re

中国古生物学会第26届学术年会

作者： Chunjiang Wang1) Maoyan Zhu2) chongyu yin3) Pengju Liu3) Jie Bai1) Yongli Li1) Xiaoyu Zhang1) Lei Wang1) Xiaofeng Xiong1) Haifeng Gai1) Yue Liu1) Baogang Li1) 1) State Key Laboratory of Oil Resource and Prospecting, China University of Petroleum, Beijing 102249, China,2) Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences, Nanjing 210008, China 3) Institute of Geology, Chinese Academy of Geosciences, Beijing 100037, China

An important increase in atmospheric oxygen appears to have taken place during the late Neoproterozoic period. This increase may have stimulated the evolution of macroscopic multicellular animals and may have led to o... 详细信息

关键词： Late Neoproterozoic Doushantuo Formation Jiulongwan oxidation biomarker

来源： cnki会议评论

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Chinese Physics B 2022年第1期31卷 458-464页

作者： Liping Liu Jin Cao Wei Guo chongyu Wang Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement(MOE) School of PhysicsBeijing Institute of TechnologyBeijing 100081China Department of Physics Tsinghua UniversityBeijing 100084China

Heavy elements(X=Ta/W/Re)play an important role in the performance of superalloys,which enhance the strength,anti-oxidation,creep resistance,and anti-corrosiveness of alloy materials in a high-temperature *** the present research,the heavy element doping effects in FCC-Ni(γ)and Ni_(3)Al(γ')systems are investigated in terms of their thermodynamic and mechanical properties,as well as electronic *** lattice constant,bulk modulus,elastic constant,and dopant formation energy in non-spin,spin polarized,and spin-orbit coupling(SOC)calculations are *** results show that the SOC effects are important in accurate electronic structure calculations for alloys with heavy *** find that including spin for bothγandγ'phases is necessary and sufficient for most cases,but the dopant formation energy is sensitive to different spin effects,for instance,in the absence of SOC,even spin-polarized calculations give 1%to 9%variance in the dopant formation energy in our *** structures calculations indicate that spin polarization causes a split in the metal d states,and SOC introduces a variance in the spin-up and spin-down states of the d states of heavy metals and reduces the magnetic moment of the system.

关键词： nickel-based superalloys Ni_(3)Al spin spin-orbit coupling mechanical properties electronic structures

Re effects in model Ni-based superalloys investigated with first-principles calculations and atom probe tomography

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Chinese Physics B 2020年第4期29卷 232-241页

作者： Dianwu Wang chongyu Wang Tao Yu Wenqing Liu Central Iron and Steel Research Institute Beijing 100081China Department of Physics Tsinghua UniversityBeijing 100084China Key Laboratory for Microstructures Shanghai UniversityShanghai 200444China

The phase partition and site preference of Re atoms in a ternary Ni-Al-Re model alloy,including the electronic structure of different Re configurations,are investigated with first-principles calculations and atom probe *** Re distribution of single,nearest neighbor(NN),next-nearest neighbor(NNN),and cluster configurations are respectively designed in the models withγandγ*** results show that the Re atoms tend to enteringγphase and the Re atoms prefer to occupy the Al sites inγ*** Re cluster with a combination of NN and NNN Re-Re pair configuration is not preferred than the isolated Re atom in the Ni-based superalloys,and the configuration with isolated Re atom is more preferred in the ***,the electronic states are analyzed and the energetic parameters are *** electronic structure analyses show there exists strong Ni-Re electronic interaction and it is mainly contributed by the d-d *** characteristic features of the electronic states of the Re doping effects are also *** is also found that Re atoms prefer the Al sites inγside at the *** density of states at or near the Fermi level and the d-d hybridizations of NN Ni-Re are found to be important in the systems.

关键词： Re distribution first-principles calculations atom probe tomography Ni-based superalloys

Scenario-based Optimal Real-time Charging Strategy of Electric Vehicles with Bayesian Long Short-term Memory Networks

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Journal of Modern Power Systems and Clean Energy 2024年第5期12卷 1572-1583页

作者： Hongtao Ren Chung-Li Tseng Fushuan Wen chongyu Wang Guoyan Chen Xiao Li the College of Electrical Engineering Zhejiang UniversityHangzhou 310027China UNSW Business School The University of New South WalesNSW 2052SydneyAustralia Hainan Institute Zhejiang UniversitySanya 572000China the Department of Electrical Engineering College of Infor‐mation Science and EngineeringHuaqiao UniversityXiamenChina Guangzhou Power Supply Bureau of Guangdong Power Grid Co. Ltd.GuangzhouChina

Joint operation optimization for electric vehicles(EVs)and on-site or adjacent photovoltaic generation(PVG)are pivotal to maintaining the security and economics of the operation of the power system *** offline optimization algorithms lack real-time applicability due to uncertainties involved in the charging service of an EV charging station(EVCS).Firstly,an optimization model for real-time EV charging strategy is proposed to address these challenges,which accounts for environmental uncertainties of an EVCS,encompassing EV arrivals,charging demands,PVG outputs,and the electricity ***,a scenario-based two-stage optimization approach is *** scenarios of the underlying uncertain environmental factors are generated by the Bayesian long short-term memory(B-LSTM)***,numerical results substantiate the efficacy of the proposed optimization approach,and demonstrate superior profitability compared with prevalent approaches.

关键词： Bayesian neural network charging strategy electric vehicle(EV) long short-term memory(LSTM) scenario analysis

A1_2O_3 Effect on the Catalytic Activity of Cu-ZnO-Al_2O_3-SiO_2 Catalysts for Dimethyl Ether Synthesis from CO_2 Hydrogenation

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Journal of Natural Gas Chemistry 2005年第3期14卷 156-162页

作者： Jiyuan Wang chongyu Zeng College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009 China

The effect of Al2O3 on the Cu-ZnO-Al2O3-SiO2 catalysts prepared by a pseudo sol-gel method has been investigated and these catalysts were characterized by XRD, H2-TPR, XPS, NH3-TPD and CO2- TPD techniques. As revealed by XRD and H2-TPR, the added alumina produces high dispersion of CuO and makes the reduction of CuO difficult. XPS analysis detects a remarkably high Al^3＋ enrichment at the surface of calcined samples, along with a decrease of Eb of Cu 2p3/2, which confirms the Cu-Al interaction. Another important role of Al203 would be to incorporate into the SiO2 structure to form the acid-base sites for ether formation. The reaction results shows that the addition of Al2O3 exhibits a promoting effect on the CO2 conversion only when its content is below 1.4%, and an optimal DME selectivity is obtained when 4.0%Al2O3 is added, indicating a better ＇synergistic effect＇ is present between the methanol forming component and the acidic component in bifunctional catalysts. Possible relationship between the catalytic activity and the Cu-Al interaction as well as the surface acidity is discussed.

关键词： carbon dioxide hydrogenation dimethyl ether copper zinc oxide alumina silicon dioxide,synthesis