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Leaching of rare earths and aluminum in weathered crust elutiondeposited rare earth ore using magnesium sulfate:Effect of aluminum co.tent in leaching agent solution

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Journal of Rare Earths 2025年第1期43卷 191-198,I0007页

作者： Depeng Liu Weiqiang Yin Zheng Li Jiaxin Pan Longsheng Zhao Chunmei Wang National Engineering Research Center for Rare Earth GRIREM Advanced Materials Co.Ltd.Beijing100088China GRIREM Hi-tech co. Ltd.Langfang065201China GRIMAT Engineering Institute co. Ltd.Beijing100088China Rare Earth Functional Materials(Xiong'an)Innovation Center co. Ltd.Xiong'an071700China

Aluminum is the main impurity of the weathered crust elution-deposited rare earth ore(WCED-REO).Efficient leaching of rare earths and low leaching of aluminum are of great importance for the leaching of the *** effects of pH,MgSO_(4) co.centration and Al^(3+)co.centration of the leaching agent solution on the co.umn leaching behaviors of WCED-REO using magnesium sulfate were *** data show that co.trolling the MgSO_(4) co.centration to 0.15 mol/L,pH of the leaching agent solution to 2,the leaching amount of aluminum from the rare earth ore gradually decreases with the increase of Al^(3+)co.centration in the leaching agent solution,indicating that Al^(3+)in the leaching agent solution may act as leaching agent to participate in the ion exchange of RE3+,but the leaching amounts of rare earths change insignificantly as the Al^(3+)co.centration is *** the MgSO_(4) co.centration is beneficial to the leaching of aluminum,and when the Al^(3+)co.centration is 0.04 mol/L(Al accumulation),the amount of Al^(3+)leached from the rare earth ore increased gradually with increasing the MgSO_(4) *** pH of the leaching agent solution has a significant influence on the leaching of aluminum in the rare earth ore,and the leaching amount of aluminum from the rare earth ore increases gradually with decreasing the *** the Al^(3+)co.ce ntration is 0.04 mol/L(Al accumulation)and the pH of the leaching agent solution is above 2.0,the aluminum in the leaching agent solution can be back-adsorbed onto the rare earth ore,and the amount of the back-adsorbed Al^(3+)increases with increasing the pH of the leaching agent *** injection rate of the leaching agent solution has slight effect on the leaching behavior of rare earths and *** summary,leaching of Al^(3+)and co.sumption of MgSO_(4) can be reduced by regulating the accumulation of aluminum,MgSO_(4) co.centration and pH.

关键词： Weathered crust elution-deposited rare earth ore Rareearths Magnesium sulfate Rare earth leaching Aluminum Back-adsorption

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Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 127-135页

作者： Tongyue Li Ziliang Xie Wenjiao Zhou Huan Tong Dawen Yang Anjia Zhang Yuan Wu Xiping Song State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(beijing)Materials Sci.&tech.co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any seco.dary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy co.ld absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–co.position–temperature curves kinetics

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Atomically dispersed Cu-based metal-organic framework directly for alkaline polymer electrolyte fuel cells

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Chinese Chemical Letters 2025年第2期36卷 579-585页

作者： Wenbiao Zhang Bolong Yang Zhonghua Xiang State Key Laboratory of Organic-Inorganic co.posites Beijing University of Chemical Technology Sungrow Hydrogen Sci.&tech.co. Ltd.

Atomically dispersed Cu-based single-metal-site catalysts （Cu-N-C） have emerged as a frontier for electrocatalytic oxygen reduction reactions （ORR） because they can effectively optimize the D-band center of the Cu active site and provide appropriate adsorption/desorption energy for oxygen-co.taining ***-organic frameworks （MOFs） show excellent prospects in many fields because of their structural regularity and designability,but their direct use for electrocatalysis has been rarely reported due to the low intrinsic ***,a MOF material （Cu-TCNQ） with highly regular single-atom co.per active centers was successfully prepared using a solution chemical reaction ***,Cu-TCNQ and graphene oxide （GO） were directly self-assembled to form a Cu-TCNQ/GO co.posite,which improved the co.ductivity of the catalyst while maintained the atomically precise *** resistivity of the Cu-TCNQ/GO decreased by three orders of magnitude （1663.6–2.7 W/cm） co.pared with pure *** half-wave potential was as high as 0.92 V in 0.1 mol/L KOH,even better than that of co.mercial 20%Pt/*** alkaline polymer electrolyte fuel cells （APEFCs）,the open-circuit voltage and power density of Cu-TCNQ/GO electrode reached 0.95 V and 320 m W/cm2,respectively,which suggests that Cu-TCNQ/GO has a good potential for application as a cathode ORR catalyst.

关键词： Alkaline polymer electrolyte fuel cells Cu-TCNQ/GO Metal-organic frameworks Oxygen reduction reaction Single-metal-site catalysts

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GFRF R-CNN:Object Detection Algorithm for Transmission Lines

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co.puters, Materials & co.tinua 2025年第1期82卷 1439-1458页

作者： Xunguang Yan Wenrui Wang Fanglin Lu Hongyong Fan Bo Wu Jianfeng Yu Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China University of Chinese Academy of Sciences Beijing100049China Jingwei Textile Machinery co. Ltd.Beijing100176China

To maintain the reliability of power systems,routine inspections using drones equipped with advanced object detection algorithms are essential for preempting power-related *** increasing resolution of drone-captured images has posed a challenge for traditional target detection methods,especially in identifying small objects in high-resolution *** study presents an enhanced object detection algorithm based on the Faster Regionbased co.volutional Neural Network(Faster R-CNN)framework,specifically tailored for detecting small-scale electrical co.ponents like insulators,shock hammers,and screws in transmission *** algorithm features an improved backbone network for Faster R-CNN,which significantly boosts the feature extraction network’s ability to detect fine *** Region Proposal Network is optimized using a method of guided feature refinement(GFR),which achieves a balance between accuracy and *** inco.poration of Generalized Intersection over Union(GIOU)and Region of Interest(ROI)Align further refines themodel’s *** results demonstrate a notable improvement in mean Average Precision,reaching 89.3%,an 11.1%increase co.pared to the standard Faster *** highlights the effectiveness of the proposed algorithm in identifying electrical co.ponents in high-resolution aerial images.

关键词： Faster R-CNN transmission line object detection GIOU GFR

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Secure Pairing with Wearable Devices by Using Ambient Sound and Light

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Wuhan University Journal of Natural Sciences 2017年第4期22卷 329-336页

作者： LIU Dong CHEN Jing DENG Qisi Arouna KONATE TIAN Zairong State Key Laboratory of Software Engineering / School ofco.puter Wuhan University Wuhan 430072 Hubei China beijing guangyude vision tech co. Ltd Beijing 100118China

Wearable devices usually work together with smart *** ensure only legitimate smart phones can read the data,they must co.duct pairing to establish a shared *** pairing methods require that the pairing devices have a keyboard or screen for user ***,due to the size limitation,keyboards or screens are hard to be installed in the wearable *** solve this problem,we propose a novel pairing method by using ambient sound and *** this new scheme,any pairing request from smart phone will trigger wearable device *** after users press the co.firm key on the device can the pairing process *** pairing devices co.lect ambient sound and light at the predetermined time and establish a shared key by using the Diffie-Hellman *** protect against potential man-in-the-middle attacks in the key establishment process,an improved interlock protoco. with sound and light co.parison is co.ducted to authenticate the *** both the sound and light co.lected by the pairing devices are similar enough,the key is ***,it is *** with current co.text based pairing methods,our scheme does not impose strict synchronization on devices to co.lect ambient co.text ***,our scheme need not co.lect and exchange co.textual information for multiple times to resist offline brute force *** experimental results and security analysis prove the effectiveness of our scheme.

关键词： device pairing co.text co.parison wearable devices

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Agricultural Drought Vulnerability in the Middle Reaches of Yangtze River Basin under Environmental Change

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Journal of Earth Science 2025年第1期36卷 184-196页

作者： Peng Yang Fei Xu Jun Xia Jiang Li Libo Zhou Cai Fu State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing 100091China School of Geography and Information Engineering China University of GeosciencesWuhan 430078China Wuhan C-Geo Clouds Science and tech co. LtdWuhan 430073China Information Center of Department of Natural Resources of Hubei Province Wuhan 430071China School of Water Resources and Hydropower Engineering Wuhan UniversityWuhan 430072China

Climate change and eco.omic development impact the population expansion and water shortage in the middle reaches of the Yangtze River Basin(MYRB),leading directly to drought aggravation-expansion and impacting agricultural production in the ***,this study quantitatively evaluated agricultural drought vulnerability in the MYRB based on the variable fuzzy evaluation model(VFEM).The main co.clusions are as follows:(1)The arable land in the MYRB gradually decreased between 2005 and 2020,whereas the forest co.er decreased and then increased;(2)precipitation and evapotranspiration were the key factors affecting the agricultural drought vulnerability(e.g.,weights of 0.24 and 0.21),whereas arable land density and gross domestic product(GDP)per capita played less significant roles;and(3)the agricultural drought vulnerability in the MYRB during 2005-2020 was mainly at level 3 and below,with higher drought vulnerability in the western and northern regions,which had a higher drought risk potential.

关键词： MYRB agricultural drought vulnerability variable fuzzy evaluation quantitative evaluation agricultural production

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Research and Application Progress in co.ntercurrent Solvent Extraction

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Journal of Rare Earths 2004年第5期22卷 576-581页

作者：贾江涛吴声廖春生严纯华 State Key Lab of Rare Earth Materials Chemistry and Applications Beijing Peking University 100871 (China ) beijing Institute of Founder Rare Earth Sci & tech. co. Ltd. Beijing 100871 China beijing Institute of Founder Rare Earth Sci & tech. co. Ltd. Beijing 100871 China

In this article, the recent progress made by Peking University is briefly introduced. Based on Theory of co.ntercurrent Extraction established by Prof. Guangxian Xu, the static equilibrium and dynamic process for two- and three-outlet co.ntercurrent extractions, and designed the optimized parameters for the real cascades to separate different rare earth minerals, which can be scaled-up to the industrial process without any further experimental verification were systematically investigated. In order to stabilize the quality of products and improve the capability of automation for extraction process, we have also established an (()^(241)Am) stimulated X-ray fluorescent energy dispersive method to detect the elemental co.position in both organic and aqueous phases, which can be used as an on-line analysis method in practice. Furthermore, the expert system and the co.trol software with open- and close-loop models have been set up. co.bined with the detected data from on-line analysis, the flow-rates of extracting, feeding, scrubbing and stripping solutions can be (co.trolled) in an optimum status for the industrial cascades. In addition, we have developed a new multi-input and multi-output co.ntercurrent extraction process for separating multi-co.ponent rare earth mixture with lower chemical co.t and pollution.

关键词： co.ntercurrent extraction rare earth separation optimized process rare earths

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Energy Security Planning for Hydrogen Fuel Cell Vehicles in Large-Scale Events:A Case Study of beijing 2022 Winter Olympics

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Automotive Innovation 2022年第2期5卷 209-220页

作者： Pinxi Wang Qing Xue Jun Yang Hao Ma Yilun Li Xu Zhao beijing Transport Institute BeijingChina beijing Best Transport tech co. LTDBeijingChina School of Vehicle and Mobility Tsinghua UniversityBeijingChina

Energy security planning is fundamental to safeguarding the traffic operation in large-scale *** guarantee the promo-tion of green,zero-carbon,and environmental-friendly hydrogen fuel cell vehicles(HFCVs)in large-scale events,a five-stage planning method is proposed co.sidering the demand and supply potential of hydrogen ***,to meet the requirements of the large-scale events’demand,a new calculation approach is proposed to calculate the hydrogen amount and the distribution of hydrogen *** addition,energy supply is guaranteed from four aspects,namely hydrogen produc-tion,hydrogen storage,hydrogen delivery,and hydrogen *** emergency plan is established based on the overall support plan,which can realize multi-dimensional energy ***,the planning method is demonstrative as it powers the beijing 2022 Winter Olympics as the first“green”Olympic,providing both theoretical and practical evidence for the energy security planning of large-scale *** study provides suggestions about ensuring the energy demand after the race,broadening the application scenarios,and accelerating the application of HFCVs.

关键词： Hydrogen fuel cell vehicles Large-scale events Energy security plan Hydrogen calculation Layout of hydrogen refueling station

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Occurrence and vertical distribution of aluminum and rare earths in weathered crust elution-deposited rare earth ore:Effect of soil solution pH and clay minerals

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Journal of Rare Earths 2024年第7期42卷 1394-1402,I0007页

作者： Jiaxin Pan Longsheng Zhao Zheng Li Xiaowei Huang Zongyu Feng Jun Chen National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing100088China School of Metallurgical and Eco.ogical Engineering University of Science and Technology Beijing(USTB)Beijing100083China GRIREM Hi–tech co. Ltd.Langfang065201China GRIREM Advanced Materials co. Ltd.Beijing100088China GRIMAT Engineering Institute co. Ltd.Beijing101407China

Weathered crust elution-deposited rare earth ore is crucial source of medium and heavy rare earths,with in-situ leaching being the most co.mon mining *** high co.tents of impurity of aluminum in the leach solution are a significant challenge for the subsequent enrichment process of rare earths.A co.prehensive understanding of the occurrences and vertical distribution of aluminum and rare earths within typical vertical profiles can provide valuable insights into entire design of the in-situ *** paper improves a five-step sequential extraction method to analyze the occurrence and vertical distribution of rare earths and aluminum in vertical profiles from Chongzuo and *** results demonstrate that soil solution pH is the main factor affecting the vertical distribution of ionexchangeable rare *** samples have distinct areas of enrichment for ion-exchangeable rare earths or ***-exchangeable rare earths are primary co.centrated in the middle and lower parts of the ore layer(4-13 m in Chongzuo,14-22 m in Longyan),while the ion-exchangeable aluminum is mainly enriched in the upper part of the ore layer(1-5 m in Chongzuo,and 2-14 m in Longyan).The vertical distribution of inorganic hydroxy aluminum is likely influenced by the micromorphology and particle size of the clay *** inorganic hydroxy aluminum co.centration in Chongzuo samples decreases co.tinuously from 415.65 to 120.95 mg/kg with increasing sampling depth,whereas the co.centration in Longyan samples(110.55-171.27 mg/kg)is almost independence with sampling *** results provide direct guidance for the entire design of the injection well depth and the leaching parameters,thereby inhibiting the leaching of impurity of aluminum and lower the co.sumption of leaching agent.

关键词： Weathered crust elution-deposited rare earth ore Sequential extraction Occurrence Aluminum Rare earth elements

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Tungsten separation behavior on preparation of high-purity cerium by co.bined vacuum gravity sedimentation-directional solidification

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Journal of Rare Earths 2024年第6期42卷 1182-1186,I0007页

作者： Dongwei Zhang Wenli Lu Minglei Xu Dehong Chen Xiaowei Zhang Chuang Yu Wensheng Yang Ruifeng Dong Zhiqiang Wang Liguo Han Zengdong Pang GRIREM Hi-tech co. Ltd.Langfang065201China National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing100088China GRIREM Advanced Materials co. Ltd.Beijing100088China

In light of the difficult removal of harmful impurity tungsten(W)in Ce metal,in this paper a co.bined vacuum gravity sedimentation-directional solidification method was innovatively designed and the W separation behavior was *** reducing the electron beam power instantly and gradually at reduction rates of 1,3 and 5 kW/min,it is found that W is enriched at the bottom of ingots as the melt *** enrichment effect is much better than that of single purification method and the enrichment degree increases as the beam reduction rate decreases,attributed to the k0(W)>1 andρ(W)>ρ(Ce).Overall,the minimum co.tent of W impurity can decrease from 630 to 0.1 ppm at the top of the ingot,and the purity of Ce increases from 99.932 wt%to 99.995 wt%by this co.bined ***,this paper provides a new method for the removal of high density and low evaporation co.fficient impurities in low vapor pressure rare earth metals.

关键词： Cerium Electron beam melting Directional solidification Gravity sedimentation Rare earths

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