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Progress in preparation of rare earth metals and alloys by electrodeposition in molten salts

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Rare Metals 2016年第11期35卷 811-825页

作者： Wei Han Mei Li Mi-Lin Zhang yong-de yan Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering University

Rare earth（RE） metals and their alloys have attracted considerable practical interests due to their functional properties. Because of their negative deposition potentials, RE metals cannot be electrochemically deposited from aqueous media. Using molten salt as medium provides a unique opportunity for the electrowinning and electrorefining of high-purity RE metals, as well as for the electrochemical formation of their alloys and intermetallic compounds. Certainly, the electrochemical behaviors of RE metals and their alloys have been investigated in a number of different molten salts comprising all-fiuorides,all-chlorides and mixed chloride-fiuoride media. Based on the results, RE and their alloys were produced by molten salt electrolysis. In this paper, the developments of preparation of RE metals and their alloys by electrolysis in molten salts in recent years were systematically summarized on both the local and international levels. Attention was paid mainly to the electrodeposition of RE metals and their alloys, including RE-Mg, RE-Al, RE-Ni, RE-Co,RE-Cu, RE-Fe and RE-Zn alloys.

关键词： Electrochemical formation Molten salts Electrolysis Rare earth Alloys

Preparation of Mg-Li alloys by electrolysis in molten salt at low temperature

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Chinese Chemical Letters 2007年第3期18卷 329-332页

作者： Mi Lin Zhang yong de yan Zhi Yao Hou Lu An Fan Zeng Chen Ding Xiang Tang College of Materials Science and Chemical Engineering Harbin Engineering University Harbin 150001 China

A new technology for preparation of low cost Mg-Li alloys was studied. The alloys were prepared by electrolysis in molten LiCl-KCl （weight ratio is 1：1） electrolyte with Mg rod severing as the consumed cathode. Main factors that affect current efficiency were investigated, and optimal electrolysis parameters were obtained. Mg-Li alloys with low lithium Content （about 25%） were prepared by the unique method of a higher post-thermal treatment temperature after electrolysis at low temperature. The results showed that the electrolysis can be carried out at low temperature, which resulted in reducing preparation cost due to energy saving. The new technology for the oreoaration of Mg-Li alloy by electrolysis in molten salt was laroved to be feasible.

关键词： Mg-Li alloys Molten salt electrolysis Low temperature Current efficiency

Recovery and separation of rare earth elements by molten salt electrolysis

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International Journal of Minerals,Metallurgy and Materials 2021年第6期28卷 899-914页

作者： Tai-qi Yin Yun Xue yong-de yan Zhen-chao Ma Fu-qiu Ma Mi-lin Zhang Gui-ling Wang Min Qiu yantai Research Institute&Graduate School Harbin Engineering UniversityYantai 264006China College of Science Heihe UniversityHeihe 164300China Zhongkexin Engineering Consulting(Beijing)Co. LtdBeijing 100039China

With the increasing demand of rare earth metals in functional materials,recovery of rare earth elements(REEs)from secondary resources has become important for the green economy *** salt electrolysis has the advantages of low water consumption and low hazardous waste during REE *** review systematically summarizes the separation and electroextraction of REEs on various reactive electrodes in different molten *** also highlights the relationship between the formed alloy phases and electrodeposition parameters,including applied potential,current,and ion ***,the feasibility of using LiF–NaF–KF electrolyte to recover REEs is evaluated through thermodynamic *** related to REE separation/recovery the choice of electrolyte are discussed in detail to realize the low-energy and high current efficiency of practical applications.

关键词： rare earth element molten salt reactive electrode electrochemical separation

Molten salt synthesis and supercapacitor properties of oxygen-vacancy LaMnO3-δ

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Journal of Energy Chemistry 2020年第4期29卷 173-181页

作者： Ya-Li Song Zi-Chang Wang yong-de yan Mi-Lin Zhang Gui-Ling Wang Tai-Qi Yin Yun Xue Fan Gao Min Qiu Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbinEngineering UniversityHarbin 150001HeilongjiangChina College of Science Heihe UniversityHeihe 164300HeilongjiangChina

Due to the unique structure of perovskite materials,their capacitance can be improved by introducing oxygen *** this paper,the LaMnO3-δ material containing oxygen vacancy was synthesized by molten salt method in KNO3-NaNO3-NaNO2 *** La-Mn-O crystal grows gradually in molten salt with the increase of *** was confirmed that LaMnO3-δ with perovskite structure and incomplete oxygen content were synthesized by molten salt method and presented a three-dimensional ***3-δ stores energy by redox reaction and adsorption of OH-in electrolyte *** comparison with the stoichiometric LaMnO3 prepared by the sol-gel method,LaMnO3-δ prepared by molten salt method proffered higher capacitance and better *** galvanostatic charge-discharge curve showed specific capacitance of 973.5 F/g under current density of 1 A/g in 6 M *** capacitance of LaMn03-δ was 82.7%under condition of 5 A/g compared with the capacitance at the current of 1A/g,and the specific capacitances of 648.0 and 310.0 F/g were obtained after 2000 and 5000 cycles of galvanostatic charging-discharging,*** salt synthesis method is relatively simple and suitable for industrial scale,presenting a promising prospect in the synthesis of perovskite oxide materials.

关键词： LaMnO3-δ Perovskite oxide KNO3-NaNO3-NaNO2 melt Supercapacitor Molten salt synthesis

Electrochemical behavior and underpotential deposition of Sm on reactive electrodes(Al,Ni,Cu and Zn)in a LiCl-KCl melt

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International Journal of Minerals,Metallurgy and Materials 2020年第12期27卷 1657-1665页

作者： Tai-qi Yin Lang Chen Yun Xue yang-hai Zheng Xue-peng Wang yong-de yan Mi-lin Zhang Gui-ling Wang Fan Gao Min Qiu College of Materials Science and Chemical Engineering Harbin Engineering UniversityHarbin 150001China College of Science Heihe universityHeihe 164300China Geely Automobile Research Institute Ningbo 315336China

Sm extraction from a LiCl-KCl melt was carried out by forming alloys on various electrodes,including Al,Ni,Cu,and liquid Zn,and the electrochemical behaviors of the resultant metal products were investigated using different electrochemical *** Sm metal deposition via the conventional two-step reaction process was not noted on the inert electrode,underpotential deposition was observed on the reactive electrodes because of the latter's depolarization *** depolarization effects of the reactive electrodes on Sm showed the order Zn>Al>Ni>***-M(M=Al,Ni,Cu,Zn)alloys were deposited by galvanostatic and potentiostatic *** products were fully characterized by X-ray diffractometry(XRD)and scanning electron microscopy(SEM)-energy dispersive spectrometry(EDS),and the stability of the obtained M-rich compounds was ***,the relationship between the electrode potential and type of Sm-M intermetallic compounds formed was assessed on the basis of the observed electrochemical properties and electrodeposits.

关键词： electrodeposits depolarization effect reactive electrodes samarium alloys

Solar cycles during the seventeenth century revealed by equatorial aurora records

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Earth and Planetary Physics 2025年第1期9卷 182-187页

作者： yong Wei LiMei yan Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Solar cycles are fundamental to astrophysics,space exploration,technological infrastructure,and Earth's climate.A better understanding of these cycles and their history can aid in risk mitigation on Earth,while also deepening our knowledge of stellar physics and solar system *** the solar cycles between 1600 and 1700-especially the post-1645 Maunder Minimum,characterized by significantly reduced solar activity-poses challenges to existing solar activity *** study utilizes a new red equatorial auroral catalog from ancient Korean texts to establish solar cycle patterns from 1623 to ***,a further reevaluation of the solar cycles between 1610 and 1755 identified a total of 13 cycles,diverging from the widely accepted record of 12 cycles during that *** research enhances our understanding of historical solar activity,and underscores the importance of integrating diverse historical sources into modern analyses.

关键词： solar cycle Maunder Minimum solar activity red equatorial aurora West Pacific geomagnetic anomaly

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正则化流形信息极端学习机

通信学报 2016年第11期37卷 57-67页

作者：刘德山楚永贺闫德勤辽宁师范大学计算机与信息技术学院辽宁大连116081

基于流形学习的思想和理论方法,提出刻画流形信息的正则化的极端学习机(MELM)算法。该算法利用流形信息刻画数据的几何结构和判别信息,克服ELM在有限样本上学习不充分的问题;能够有效提取数据样本的判别信息避免数据样本信息重叠;利用... 详细信息

基于流形学习的思想和理论方法,提出刻画流形信息的正则化的极端学习机(MELM)算法。该算法利用流形信息刻画数据的几何结构和判别信息,克服ELM在有限样本上学习不充分的问题;能够有效提取数据样本的判别信息避免数据样本信息重叠;利用最大边际准则有效解决类间散度矩阵和类内散度矩阵的奇异问题。为验证所提方法的有效性,实验使用普遍应用的图像数据,将MELM与ELM以及相关最新算法RAFELM、GELM进行识别率和计算效率的对比。实验结果表明,该算法能够显著提高ELM的分类准确率和泛化能力,并且优于其他相关算法。

关键词：极端学习机几何结构流形信息机器学习

Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期68卷 249-256页

作者： Qing-Yun Fang Chengyihan Gu Yinghan Chen Wencheng yan yong Liang Weipeng Li Chengjian Zhu Jie Han Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

关键词： gold catalysis peptide alkylation C-C coupling radical

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Electrodeposition of quarternary Mg-Zn-Li-Ca alloys from molten salts

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Transactions of Nonferrous Metals Society of China 2013年第3期23卷 861-865页

作者：曹鹏张密林韩伟颜永得陈丽军哈尔滨工程大学教育部超轻材料与表面技术重点实验室哈尔滨150001

Direct electrodeposition of quarternary Mg-Zn-Li-Ca alloys on a molybdenum electrode from LiCl-KCl-MgCl2-ZnCl2-CaCl2 melts at 943 K was *** voltammograms（CVs） show that the deposition potential of Li shifts in a positive direction after adding MgCl2,ZnCl2 and *** measurements indicate that the codepositon of Mg,Li,Zn,and Ca occurs at current densities lower than-1.55 A/cm2.X-ray diffraction（XRD） indicates that Mg-Zn-Li-Ca alloys with different phases were prepared via galvanostatic *** microstructures of typical phase of Mg-Zn-Li-Ca alloys were characterized by optical microscopy（OM） and scanning electron microscopy（SEM）.The analysis of energy dispersive spectrometry（EDS） shows that elements of Mg and Ca distribute homogeneously in the Mg-Zn-Li-Ca ***,element Zn mainly locates at the edges of the domain.

关键词： Mg-Zn-Li-Ca alloys electrolysis cyclic voltammetry molten salt