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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 320-326页

作者：李涛凌帅 ZHONG Shujie LOU Qiongyue Department of Materials engineering School of Mechanical EngineeringChengdu UniversityChengdu 610106China

Ni^(2+)/Cu^(2+)/SO_(4)^(2-)/polyvinyl alcohol precursor fibers with uniform diameters were prepared through ***-based composite nanoalloys containing Ni,Cu,and S were prepared through heat treatment in an Ar *** experimental results show that the main components of the prepared nanoalloys are NiCu,Ni_(3)S_(2),Ni,and *** nanoalloys exhibit fine grain sizes about 200-500 nm,which can increase with increasing heat treatment *** test results show that the nickel sulfidemodified NiCu nanoalloy composites exhibit excellent oxygen evolution reaction properties,and the oxygen evolution reaction properties gradually improve with the increasing heat treatment *** sample prepared at 1 000℃ for 40 min show a low overpotential of 423 mV and a small Tafel slope of 134 mV·dec^(-1) at a current density of 10 mA·cm^(-2).

关键词： NiCu nanoalloy Ni_(3)S_(2) structure transformation oxygen evolution reaction

An experimental and theoretical study on photoluminescence of Ce^(3+)-doped ZnS quantum dots and their application in Aspergillus oryzae

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Journal of Rare Earths 2024年第6期42卷 1020-1028,I0001页

作者： Yan Lei Guangzhi Zhang Yitong Yao Gaiqin Zhu Zhong Chen Jiangrong Dan Hua Liu Shuwang Duo school of Materials and mechanical and electrical engineeringJiangxi Science and Technology Normal University Nanchang330013China

ZnS and ZnS:3.125%Ce^(3+)(ZSC)quantum dots(QDs)were synthesized by a low-temperature solid-phase *** crystal structure,photoluminescence(PL)properties of ZSC QDs,and their effects on the growth and kojic acid production of Aspergillus oryzae(***)were *** is found that both QDs have a cubic blend structure with the average particle size ranging of 2.75-6.14 ***^(3+)doping not only increases the band gap of ZnS QDs from 3.43 to 3.48 eV,but also increases the PL intensity by about 2.23 times,which is due to the fact that the electron carrier concentration is improved,and then the rate of radiative recombination is *** integral emission intensity,biomass,extracellular proteins yield,and kojic acid production of *** cultured with ZSC(ZnS)QDs are about 4.31(3.23),1.61(1.20),1.12(1.09),and 2.99(1.68)times higher than that of medium without QDs,respectively.

关键词： Zns Quantum dots Doping First-principles calculations Aspergllus oryzae Rare earths

Coercivity mechanism of high-performance anisotropic heterostructure SmCo5 magnets

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Journal of Rare Earths 2024年第10期42卷 1882-1888页

作者： Yuan Teng Yuqing Li Weiqiang Liu Xiaochang Xu Zhanjia Wang Jianjun Yang Dongtao Zhang Hongguo Zhang Qingmei Lu Qiong Wu Weixing Xia Ming Yue Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of Technology school of mechanical and electrical engineering Henan Institute of Science and Technology school of mechanical engineering Anyang Institute of Technology Key Laboratory of Magnetic Materials and Devices Ningbo Institute of Material Technology and EngineeringChinese Academy of Sciences

Due to its large magnetocrystalline anisotropy field and high Curie temperature,SmCo-based magnets are irreplaceable in high-temperature applications,The hot-deformed SmCo-based magnets are especially attractive for their excellent corrosion resistance,making them more suitable for harsh ***,it is still challenging for hot-deformed SmCo-based magnets to obtain high magnetization and high coercivity ***,it is necessary to analyze the relationship between its microstructure and magnetic properties and explore its magnetic hardening mechanism to guide the further improvement of magnetic *** this paper,the anisotropic heterostructure SmCo5magnet was prepared by combining large height-reduction and introducing a nano-grained Smrich *** c-axis texture,（BH）m of 16.1 MGOe,and Hciof 9.6 kOe were obtained via the heterostructure with SmCo5micron-grain and Sm-rich nano-scale *** magnetic domain observation and technical magnetization analysis demonstrate that the coe rcivity mechanism is dominated by *** results also show that the smooth and Sm-rich precipitated grain boundary provides weak pinning *** provides a reference for the development of high-pe rformance nanocrystalline SmCo5magnets.

关键词： Coercivity mechanism Heterostructure Hot-deformed SmCo magnet Permanent magnet Rare earths

Composite Braking Control Strategy for Electromechanical-Hydraulic Vehicles

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1722-1732页

作者： Zewen Meng Jichao Hong Hongxin Zhang Tiezhu Zhang Xiaoming Xu Qinghai Zhao Jian Yang College of mechanical and electrical engineering Qingdao UniversityQingdao 260071China Power Integration and Energy Storage Systems engineering Technology Center(Qingdao) Qingdao 260071China school of mechanical engineering University of Science and Technology BeijingBeijing 100083China Shunde Graduate school of University of Science and Technology Beijing Foshan 528000China

Short driving ranges and low braking energy recovery efficiencies are two recognized technical bottlenecks to be overcome in electric vehicles. In this paper, a novel electromechanical-hydraulic coupling system is proposed and integrated as a powertrain for electric vehicles, which can assist the electric vehicle to fully utilize its braking energy. The hydraulic regenerative braking force and electric regenerative braking force can provide all the braking needs using the medium and small braking intensities. Furthermore, an improved compound brake control strategy based on the braking force distribution is proposed and simulated. The results show that under the premise of ensuring braking stability, the electromechanical-hydraulic coupling driving electric vehicle can adapt to various working conditions with excellent energy-saving results. The hydraulic accumulator recovery efficiency is above 99%, and the state of charge consumption rate of the battery pack can be reduced by more than 9%. More importantly, the proposed hybrid power system can significantly improve the driving range and energy efficiency, as well as reduce the consumers' mileage anxiety in electric vehicles.

关键词： Braking control strategy electric vehicle electromechanical-hydraulic coupling energy recovery state of charge

Numerical simulation and parameter optimization of Coriolis force scale measurement process based on DEM

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Particuology 2024年第7期90卷 128-139页

作者： Haiting Liu Yong Yang Xiangliang Wang Jiewen Deng Bingbing Wang school of Energy and Power engineering Northeast Electric Power UniversityJilin132012China CNBM Hefei mechanical&electrical engineering Technology Co.Ltd Hefei230051China

The Coriolis force method is a recently developed and highly regarded direct measurement technique that enables high-precision measurement of bulk *** operational parameters and variations thereof directly influence the measurement accuracy of the *** this study,a measurement correction coefficient is introduced to improve the calculation method for mass flow rate of the *** DEM is employed to simulate the motion of particle groups within the Coriolis force scale under different parameters,and the effects of various structural and operational parameters on the measurement results are *** research findings indicate that a lower rotational speed leads to more stable instantaneous measurement results,although the measurement error is relatively *** the rotational speed exceeds 300 rpm,the measurement error remains within 15%.For materials with a radius of 1–2 mm,the variation range of precision error is approximately 0.4%.Among the structural parameters,the radius of the measurement wheel has the most significant impact on the measurement results,wherein a larger measurement wheel radius corresponds to a smaller measurement *** horizontal angle of the blades follows as the next influential parameter,with a clockwise rotation and a horizontal angle of 30°resulting in a measurement error below 2%.

关键词： Parameter optimization Discrete element method Coriolis force scale Measurement error Numerical simulation

An Integrated Control Framework for Torque Vectoring and Active Suspension System

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Chinese Journal of mechanical engineering 2024年第1期37卷 62-73页

作者： Jiwei Feng Jinhao Liang Yanbo Lu Weichao Zhuang Dawei Pi Guodong Yin Liwei Xu Pai Peng Chaobin Zhou school of mechanical engineering Southeast UniversityNanjing 211189China school of mechanical engineering Nanjing University of Science and TechnologyNanjing 210094China school of Mechano-Electronic engineering Lanzhou University of TechnologyLanzhou 730050China

Four-wheel independently driven electric vehicles(FWID-EV)endow a flexible and scalable control framework to improve vehicle *** paper integrates the torque vectoring and active suspension system(ASS)to enhance the vehicle’s longitudinal and vertical motion control *** the nonlinear characteristic of the tire model leads to a relatively heavier computational *** facilitate the controller design and ease the load,a half-vehicle dynamics system is built and simplified to the linear-time-varying(LTV)*** a model predictive controller is developed by formulating the objective function by comprehensively considering the safety,energy-saving and comfort *** in-wheel motor efficiency and the power loss of tire slip are treated as optimization indices in this work to reduce energy ***,the effectiveness of the proposed controller is verified through the rapid-control-prototype(RCP)*** results demonstrate the enhancement of the energy-saving as well as comfort on the basis of vehicle stability.

关键词： Four-wheel independently driven electric vehicles Tire nonlinearity Linear-time-varying(LTV)model Model predictive control Rapid control prototype

Numerical simulation on the multiphase flow and reoxidation of the molten steel in a two-strand tundish during ladle change

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1540-1553页

作者： Jingcheng Wang Zhentong Liu Wei Chen Hongliang Chen Lifeng Zhang school of mechanical engineering Yanshan UniversityQinhuangdao 066004China school of Materials Science and engineering Tianjin UniversityTianjin 300350China school of mechanical and Materials engineering North China University of TechnologyBeijing 100144China

A 3D mathematical model was proposed to investigate the molten steel–slag–air multiphase flow in a two-strand slab continuous casting(CC)tundish during ladle *** study focused on the exposure of the molten steel and the subsequent reoxidation *** exposure of the molten steel was calculated using the coupled realizable k–εmodel and volume of fluid(VOF)*** diffusion of dissolved oxygen was determined by solving the user-defined scalar(UDS)***,the user-defined function(UDF)was used to describe the source term in the UDS equation and determine the oxidation rate and oxidation *** effect of the refilling speed on the molten steel exposure and dissolved oxygen content was also *** the refilling speed during ladle change reduced the refilling time and the exposure duration of the molten ***,the elevated refilling speed enlarged the slag eyes and increased the average dissolved oxygen content within the tundish,thereby exacerbating the reoxidation *** addition,the time required for the molten steel with a high dissolved oxygen content to exit the tundish varied with the refilling *** the inlet speed was 3.0 m·s^(-1)during ladle change,the molten steel with a high dissolved oxygen content exited the outlet in a short period,reaching a maximum dissolved oxygen content of 0.000525wt%.Conversely,when the inlet speed was 1.8 m·s^(-1),the maximum dissolved oxygen content was 0.000382wt%.The refilling speed during the ladle change process must be appropriately decreased to minimize reoxidation effects and enhance the steel product quality.

关键词： tundish ladle change reoxidation multiphase flow numerical simulation

Entropy variances of pure coherent states in the diffusion channel

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Chinese Physics B 2024年第9期33卷 384-388页

作者： Wei-Feng Wu Yong Fang Peng Fu school of mechanical and electrical engineering Chizhou UniversityChizhou 247000China Anhui Research Center of Semiconductor Industry Generic Technology Chizhou 247000China

Using the operator correspondence of the real and fictious modes in the thermo entangled state representation, wesolve the quantum master equation describing the diffusion channel and obtain the Kraus operator-sum representation ofits analytical solution. we find that the pure coherent states evolve into the new mixed thermal superposed states in thediffusion channel. Also, we investigate the statistical properties of the initial coherent states and their entropy evolutions inthe diffusion channel, and find that the entropy evolutions are only related to the decay time and without the amplitudes ofthe initial coherent states.

关键词： entangled state representation diffusion channel coherent state entropy evolution

Characteristic Analysis of Power Oscillations Caused by Disharmony Among Voltage-source-controlled Units in Three-terminal Local Power Grid

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1295-1308页

作者： Qiyi Yu Yi Tang school of electrical engineering Southeast UniversityNanjing 210018China

Previous studies have demonstrated that disharmo-ny among voltage-source-controlled units(VSCUs)may occur on an alternating current(AC)transmission or distribution line under steady-state operating conditions(SSOCs)or quasi-static operating conditions(QSSOCs).As the studies on frequency dis-harmony have been expanded to multiple disharmonized vS-CUs in the local power grid,its adverse effects on AC lines and equivalent load(EL)at the bus without active voltage control ability(non-active bus)need to be investigated ***-ering the locality of disharmony and common topological con-nections among VSCUs,this paper adopts a Y-type three-termi-nal local power grid(LPG)as the research *** dishar-mony among the three VSCUs is ***,for the load at non-active bus,the formulas for single-phase instantaneous voltage,load current,load power,as well as average power un-der disharmony operating conditions(DOCs)are *** characteristic indicators of the above electrical quantities are defined,which can measure the amplification and reduction de-grees of the above electrical quantities before and after ***,for the line directly connected to VSCUs,the formulas for single-phase instantaneous line current and power and the average power under DOCs are *** character-istic indicators of power flow are defined,which can be used to quantify the peak amplification impact of oscillation before and after ***,the case study on the Y-type three-terminal LPG under the single-disharmony and the multi-dis-harmony switching scenarios indicates that the long-period pow-er oscillation caused by disharmony may occur in the load flow at the non-active bus and the line *** oscillation causes a serious decrease in load capability and a significant amplifica-tion of the peak of line power oscillation.

关键词： New power system power oscillation disharmony voltage-source-controlled unit(VSCU) characteristic analysis

Deterministic and Robust Volt-var Control Methods of Power System Based on Convex Deep Learning

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 719-729页

作者： Qing Ma Changhong Deng the school of electrical engineering and Automation Wuhan UniversityWuhanChina

Volt-var control(VVC)is essentially a non-convex optimization problem due to the non-convexity of power flow(PF)constraints,resulting in the difficulty in obtaining the optimum without convexity *** existing second-order cone method for the convexity conversion often leads to a sharp increase in PF constraints and optimization variables,which in turn increases the optimization difficulty or even leads to optimization *** paper first proposes a deterministic VVC method based on convex deep learning power flow(DLPF).This method uses the input convex neural network(ICNN)to establish a single convex mapping between state parameters and node voltage to complete the convexity conversion while the optimization variables only correspond to reactive power equipment,which can ensure the global optimum with extremely fast computation *** cope with the impact brought by the uncertainty of distributed energy and omit the additional worst scenario search of traditional robust VVC,this paper proposes robust VVC method based on convex deep learning interval power flow(DLIPF),which continues to adopt ICNN to establish another convex mapping between state parameters and node voltage *** DLIPF with DLPF,this method decreases the modeling and optimization difficulty of robust VVC *** results on 30-bus,118-bus,and 200-bus systems prove the correctness and rapidity of the proposed methods.

关键词： Volt-var control convexity conversion convex deep learning power flow