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CSEE Journal of Power and Energy Systems 2024年第2期10卷 756-766页

作者： Yanxiong Lei Guiping du Tuhuan li Wenjie Ma Xueyi Wang School of Electric Power South China University of TechnologyGuangzhou 510641China

Integrated battery chargers are highly effective for saving costs and improving the power density of on-board chargers in electric vehicles (EVs), However, achieving torque elimination of the commonly used three-phase (3p) motors during the fast-charging process is challenging. In this paper, the general torque cancelation law applied in 3p permanent magnet synchronous motors (PMSMs) and induction motors (IMs) is derived to design high power density integrated fast battery chargers. Two novel integrated systems with fast-charging and vehicle-to-grid (V2G) capabilities are proposed based on this law. The main advantages of the proposed systems are: (1) Two filter inductors are constituted by the stator windings while charging, and only one external inductor and several contactors are supplemented to the motor-drive circuit. Therefore, the proposed integrated systems possess high power density;(2) The 3p open-winding (OW) motor is employed, with no need to modify the propulsion system or redesign the interior structure of the motor;(3) Employing an individual controller for each phase of the inner current loop control, the proposed systems realize unity power factors and low current harmonics in the fast-charging and V2G mode. Simulation and experimental results verify the feasibility of the proposed topologies and control strategies.

关键词： Electric vehicles(EVs) fast charging integrated battery charger 3p PMSM/IM torque cancelation

Synergistic Effects of Carbon Nanotube(CNT)and Reduced Graphene Oxide(RGO)on Mechanical and Thermal Properties of ZK61 Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 577-585页

作者： Fanjing Meng Wenbo du Ning Ding Jian Sun Xian du Ke liu Shubo li College of Materials Science and Engineering Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China

The hybrid of carbon nanotube(CNT)and reduced graphene oxide(RGO)reinforced ZK61 composite was fabricated by a hot extrusion *** with the raw ZK61 alloy and single-reinforced composites,the hybrid-reinforced by RGO+CNT complex exhibited significant enhancements both in mechanical and thermal *** adjusting the proportion of RGO and CNT in ZK61 alloy,the obtained optimum ZK61/(0.06 wt%RGO+0.54 wt%CNT)composite exhibited increase of 25.4%in yield strength,26.5%in ultimate tensile strength,104%in failure strain and 30.4%in thermal conductivity,respectively,in comparison with ZK61 *** superior properties of the nano-hybrid composite are attributed to the synergetic effects of RGO and CNT,leading to a uniform dispersion and integrated structure as well as the enhanced interfacial bonding with *** strengthening ability of RGO and CNT was calculated to quantify their individual contribution to the improvement in mechanical and thermal properties of the ZK61 matrix *** RGO+CNT hybrids provide a promising way to develop Mg matrix composites with impressive performances.

关键词： Mg matrix composite Carbon nanotube Reduced graphene oxide Mechanical performance Thermal conductivity

Efficient nitrite-to-ammonia electroreduction over Zr-Ni frustrated Lewis acid-base pairs

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Science China Chemistry 2024年第5期67卷 1707-1714页

作者： Ying Zhang Zhuohang li Wenyu du Kai Chen Ke Chu School of Materials Science and Engineering Lanzhou Jiaotong UniversityLanzhou 730070China

Electrochemical NO_(2)~--to-NH_(3) conversion(NO_(2)RR) offers a green route to NH_(3) electrosynthesis, while developing efficient NO_(2)RR catalysis systems at high current densities remains a grand challenge. Herein, we report an efficient Zr-NiO catalyst with atomically dispersed Zr-dopants incorporated in NiO lattice, delivering the exceptional NO_(2)RR performance with industriallevel current density(>0.2 A cm^(-2)). In situ spectroscopic measurements and theoretical simulations reveal the construction of ZrNi frustrated Lewis acid-base pairs(FLPs) on Zr-Ni O, which can substantially increase the number of absorbed nitrite(NO_(2)~-),promote the activation and protonation of NO_(2)~- and concurrently hamper the H coverage, boosting the activity and selectivity of Zr-NiO towards the NO_(2)RR. Remarkably, Zr-NiO exhibits the exceptional performance in a flow cell with high Faradaic efficiency for NH_(3) of 94.0% and NH_(3)yield rate of 1,394.1 μmol h^(-1)cm^(-2) at an industrial-level current density of 228.2 m A cm^(-2),placing it among the best NO_(2)RR electrocatalysts for NH_(3) production.

关键词： electrochemical nitrite-to-ammonia conversion frustrated Lewis acid-base pairs(FLPs) in situ spectroscopy theoretical computations

Distributed power conditioning unit of large-scale space solar power station

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Chinese Journal of Aeronautics 2024年第8期37卷 421-434页

作者： Xintong li Jianwei MI Yiqun ZHANG Guanheng FAN Jie du School of Mechano-electronic Engineering Xidian UniversityXi’an 710071China Shaanxi Key Laboratory of Space Solar Power Station System Xidian UniversityXi’an 710071China Academy of Advanced Interdisciplinary Research Xidian UniversityXi’an 710071China

In this paper,a multi-bus distributed Power Conditioning Unit(PCU)is proposed for the Space Solar Power Station with large scale photovoltaic(PV)array and power levels reaching MW *** this unit,there are multiple independent PV *** each PV array,there are multiple independent PV *** this paper,a V-P droop control method with adaptive droop coefficient is proposed,which modifies the droop intercept based on the bus voltage deviation and the power per unit value of the PV *** method ensures the accuracy of bus voltage and achieves proportional distribution of power between PV arrays based on the proposed topology structure in this *** the load changes or the output power of the PV array fluctuates,this method can ensure that power is distributed *** principle and control method of the proposed droop control method is analyzed in this *** effectiveness of the method is verified through MATLAB/Simulink simulation and *** and experimental results show that the proposed method can achieve power distributed proportionally when load changes and PV output power fluctuates,reduce bus voltage error caused by line impedance and differences in rated power of different PV arrays,and improve the performance of PV power generation system applied to space.

关键词： Space Solar Power Station Photovoltaics Droop control DC confluence Power conditioning unit

A stepwise approach to enhancing flotation of low-grade zinnwaldite through the cationic/DL-2-octanol/anionic reagent combinations: Behavior and mechanism analysis

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International Journal of Mining Science and Technology 2024年第6期34卷 881-891页

作者： Zhonghua Xue Yali Feng Haoran li Jinrong Ju Xingquan du School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

In order to alleviate the pressure on the supply of lithium resources, this research proposes the use of binary/ternary collectors with high selectivity and collecting ability to enhance the flotation purification of low-grade zinnwaldite ore. The binary collector is a mixture of dodecylamine polyoxyethylene ether and DL-2-octanol. A binary collector is added first, followed by sodium oleate, known as a ternary collector. Under acidic conditions, the recovery of li2O in the concentrate was increased by 8.26% with the binary collector and 13.70% with the ternary collector, compared to the dodecylamine polyoxyethylene ether. The binary collector enhanced the dispersibility of the single collector, while co-adsorption strengthened the hydrophobic nature of the zinnwaldite surface. Consequently, zinnwaldite particles,after the application of binary collector, displayed inter-particle flocculation and attachment to bubbles within 60×10^(-9)m compared to other particles. Ternary collector exhibited the capacity to lower critical micelle concentration and surface tension, subsequently inducing a denser and thicker hydrophobic layer through electrostatic forces, hydrophobic interactions, and chemical reactions. The objective of this research is to facilitate the recovery of lithium resources from low-grade ores in order to meet the needs of sustainable development.

关键词： Zinnwaldite Molecular dynamics simulation Flotation Ternary collector Extended DLVO theory

Amide naphthotubes:Biomimetic macrocycles for selective molecular recognition

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Chinese Chemical Letters 2024年第4期35卷 124-131页

作者： Cheng-Da Zhao Huan Yao Shi-Yao li Fangfang du li-li Wang liu-Pan Yang School of Pharmaceutical Science Postdoctoral Research Station of Basic MedicineHengyang Medical SchoolUniversity of South ChinaHengyang 421001China

Selective molecular recognition in water is routine for bioreceptors,but remains challenging for synthetic *** is principally because noncovalent interactions are usually less efficient in aqueous *** mimicking the cavity feature of bioreceptors,*** Jiang proposed and clarified the concept of“endo-functionalized cavity”.Through situating polar binding sites into a deep hydrophobic cavity,we designed and synthesized several macrocyclic hosts,among which amide naphthotubes are the most *** hosts can selectively recognize various polar molecules including organic micropollutants,drug molecules,and chiral molecules in water by employing the hydrophobic effect and shielded hydrogen *** addition,these biomimetic hosts have been applied in spectroscopic analysis,adsorptive separation and *** this review,we provide an overview of recent advances on amide naphthotubes with special emphasis on the efforts of Jiang's *** are convinced that these biomimetic macrocycles will make further contributions to supramolecular chemistry and beyond.

关键词： Molecular recognition Supramolecular chemistry Amide naphthotube Endo-functionalized cavity Biomimetic macrocycle

Evaluation of E-sail parameters on central spacecraft attitude stability using a high-fidelity rigid–flexible coupling model

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Astrodynamics 2024年第2期8卷 271-284页

作者： Chonggang du Zheng H.Zhu Changqing Wang Aijun li Tuanjie li School of Electro-Mechanical Engineering Xidian UniversityXi’an 710071China Department of Mechanical Engineering York University4700 Keele StreetTorontoOntario M3J 1P3Canada School of Automation Northwestern Polytechnical UniversityXi’an 710129China

This study examines the impact of electric solar wind sail(E-sail)parameters on the attitude stability of E-sail’s central spacecraft by using a comprehensive rigid–flexible coupling dynamic *** this model,the nodal position finite element method is used to model the elastic deformation of the tethers through interconnected two-node tensile *** attitude dynamics of the central spacecraft is described using a natural coordinate *** rigid–flexible coupling between the central spacecraft and its flexible tethers is established using Lagrange *** research reveals the significant influences of parameters such as tether numbers,tether’s electric potential,and solar wind velocity on attitude ***,solar wind fluctuations and the distribution of electric potential on the main tethers considerably affect the attitude stability of the *** consistent management,the angular velocities of the spacecraft must remain at target ***,the attitude stability of a spacecraft has a pronounced dependence on the geometrical configuration of the E-sail,with axisymmetric E-sails proving to be more stable.

关键词： electric solar wind sail(E-sail) space tether nodal position finite element method(NPFEM) natural coordinate formulation (NCF) attitude stability

SEI/dead li-turning capacity loss for high-performance anode-free solid-state lithium batteries

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Journal of Energy Chemistry 2024年第9期96卷 145-152页

作者： Qianwen Yin Tianyu li Hongzhang Zhang Guiming Zhong Xiaofei Yang Xianfeng li Division of Energy Storage Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Long-duration and Large-Scale Energy Storage Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Laboratory of Advanced Spectro-Electrochemistry and lithium-Ion Batteries Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Anode-free solid-state lithium metal batteries(AF-SSLBs)have the potential to deliver higher energy density and improved safety beyond lithium-metal ***,the unclear mechanism for the fast capacity decay in AF-SSLBs,either determined by dead li or solid electrolyte interface(SEI),limits the proposal of effective strategies to prolong cycling *** clarify the underlying mechanism,herein,the evolution of SEI and dead li is quantitatively analyzed by a solid-state nuclear magnetic resonance(ss-NMR)technology in a typical liPF6-based polymer *** results show that the initial capacity loss is attributed to the formation of SEI,while the dead li dominates the following capacity loss and the growth rate is 0.141 mA h cm^(−2)cycle−*** reduce the active li loss,the combination of inorganic-rich SEI and self-healing electrostatic shield effect is proposed to improve the reversibility of li deposition/dissolution behavior,which reduces the capacity loss rate for the initial SEI and following dead li generation by 2.3 and 20.1 folds,*** a result,the initial Coulombic efficiency(ICE)and stable CE increase by 15.1%and 15.3%in li-Cu cells,which guides the rational design of high-performance AF-SSLBs.

关键词： Solid-state lithium batteries Solid-state NMR Anode-free SEI Dead li

Characteristics and mechanism of Ni^(2+)and Cd^(2+)adsorption by recovered perlite from agar extraction residue

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Chinese Journal of Chemical Engineering 2024年第8期72卷 141-152页

作者： Juan Wang Yanbing Zhu Zedong Jiang Xiping du Mingjing Zheng lijun li Hui Ni Yuanpeng Wang Zhipeng li Qingbiao li College of Ocean Food and Biological Engineering Jimei UniversityXiamen 361021China Fujian Provincial Key Laboratory of Food Microbiology and Enzyme Engineering Xiamen 361021China Research Center of Food Biotechnology of Xiamen City Xiamen 361021China Xiamen Ocean Vocational College Xiamen 361021China College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361021China

Ni^(2+)and Cd^(2+)in wastewater accumulated through the ecological chain and could jeopardize human *** of Ni^(2+)and Cd^(2+)from wastewater using recovered perlite was an important way to solve the problem of resource utilization of solid waste from agar *** previous study confirmed that recovered perlite from agar extraction residue had better pore size and specific surface area than commercial ***,the adsorption efficiency and adsorption mechanism of recovered perlite were the main factors limiting its adsorption *** adsorption process of Ni^(2+)and Cd^(2+)by recovered perlite in aqueous solution was described by the pseudo-second-order kinetic equation,and the relevant adsorption mechanism was mainly *** with commercial perlite,the adsorption removal rate of Ni^(2+)and Cd^(2+)by enzymatic recovered perlite could reach 92.9%and 89.2%,respectively,and were improved by 12.63%and 13.03%.Langmuir isothermal adsorption model could better describe the isothermal adsorption process of recovered perlite on heavy metal Ni^(2+)and Cd^(2+),and the relevant adsorption mechanism was mainly monolayer *** X-ray photoelectron spectroscopy(XPS)results indicated that the decrease of Si—O Si^(2+)hydroxyl coordination bond and the increase of C—Si bond might make the binding effect of recovered perlite with heavy metals *** competitive adsorption of Ni^(2+)and Cd^(2+)by recovered perlite was still dominated by chemisorption and monolayer *** study was expected to provide a theoretical basis and technical support for the removal of Ni^(2+)and Cd^(2+)from wastewater using recovered perlite from seaweed residue.

关键词： Agar extraction residue Recovered perlite Heavy metal ion Adsorption property

Effects of deformation temperatures on microstructures,aging behaviors and mechanical properties of Mg-Gd-Er-Zr alloys fabricated by hard-plate rolling

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Journal of Magnesium and Alloys 2024年第6期12卷 2345-2359页

作者： Ke liu Dalong Hu Feng Lou Zijian Yu Shubo li Xian du Wenbo du Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China

In this investigation,a high-strength Mg-12Gd-1.0Er-0.5Zr(wt.%)alloy sheet was produced by hot extrusion(HE)and subsequent hard-plate rolling(HPR)at different *** results indicate that the microstructures of these final-rolled sheets are inhomogeneous,mainly including coarse deformed grains and dynamic recrystallized(DRXed)grains,and the volume fraction of these coarse deformed grains increases as the rolling temperature ***,more DRXed grains can be found in R-385℃sheet,resulting in a smaller average grain size and weaker basal texture,while the biggest grains and the highest strong basal texture are present in R-450℃*** of dynamic precipitation ofβphases which are mainly determined by the rolling temperature are present in these sheets,and its precipitation can consume the content of Gd solutes in the *** a result,the lowest number density ofβphase in R-450℃sheet is beneficial to modify the age hardening ***,the R-450℃sheet displays the best age hardening response because of a severe traditional precipitation ofβ’(more)andβH/βM(less)precipitates,resulting in a sharp improvement in strength,*** tensile strength(UTS)of∼518±17 MPa and yield strength(YS)of∼438±18 ***,the elongation(EL)of this sheet reduces greatly,and its value is∼2.7±0.3%.By contrasting,the EL of the peak-aging R-385℃sheet keeps better,changing from∼4.9±1.2%to∼4.8±1.4%due to a novel dislocation-induced chain-like precipitate which is helpful to keep good balance between strength and ductility.

关键词： Mg-Gd-Er-Zr sheets Age hardening response Precipitates Mechanical properties