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Progress in green and efficient enrichment of rare earth from leaching liquor of ion adsorption type rare earth ores

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Journal of Rare Earths 2022年第3期40卷 353-364,I0001页

作者： Qiang He jiang qiu Jinfa Chen Miaomiao Zan Yanfei Xiao Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China Ganzhou Engineering Technology Research Center of Green Metallurgy and Process Intensification Ganzhou 341000China

Ion adsorption type rare earth ores(IATREOs)are a valuable strategic mineral resource in China,which feature a complete composition of fifteen rare earth elements and are rich in medium and heavy rare earth(RE)*** the leaching process for recovering rare earth elements from IATREOs,many impurities will be leached together with rare earth elements and enter the leaching *** impurity removal-precipitation enrichment technique is currently applied to selectively recovery rare earth elements from the leaching liquor with the high content of impurities and low concentration of rare earth elements by using ammonium bicarbonate in the ***,a high loss of rare earth elements and severe ammonia nitrogen pollution are caused by this ***,more beneficial impurities removal technologies,mainly for aluminum,and green enrichment technologies with lower pollution are now urgently *** this purpose,this paper analyzed two aspects of research progress in recent decades:the green separation of rare earth elements and aluminum from leaching liquor and the green and efficient enrichment of rare earth ***,an approach for the high-efficiency and green enrichment of rare earth elements from leaching liquor of the IATREOs is proposed in several aspects,including impurity inhibition leaching,neutralization and impurity removal,alkaline calcium and magnesium salt precipitation enrichment,and centrifugal extraction enrichment.

关键词： Ion adsorption type rare earth ores Leaching liquor Rare earth Aluminum Separation Non-ammonia enrichment

Evaluation of liquefaction-induced lateral displacement using Bayesian belief networks

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Frontiers of Structural and Civil Engineering 2021年第1期15卷 80-98页

作者： Mahmood AHMAD Xiao-Wei TANG jiang-Nan qiu Feezan AHMAD State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Department of Civil Engineering University of Engineering and Technology Peshawar(Bannu Campus)Bannu 28100Pakistan Faculty of Management and Economics Dalian University of TechnologyDalian 116024China Department of Civil Engineering Abasyn UniversityPeshawar 25000Pakistan

Liquefaction-induced lateral displacement is responsible for considerable damage to engineered structures during major ***,an accurate estimation of lateral displacement in liquefaction-prone regions is an essential task for geotechnical experts for sustainable *** paper presents a novel probabilistic framework for evaluating liquefaction-induced lateral displacement using the Bayesian belief network(BBN)approach based on an interpretive structural modeling *** BBN models are trained and tested using a wide-range casehistory records *** two BBN models are proposed to predict lateral displacements for free-face and sloping ground *** predictive performance results of the proposed BBN models are compared with those of frequently used multiple linear regression and genetic programming *** results reveal that the BBN models are able to learn complex relationships between lateral displacement and its influencing factors as cause-effect relationships,with reasonable *** study also presents a sensitivity analysis to evaluate the impacts of input factors on the lateral displacement.

关键词： Bayesian belief network seismically induced soil liquefaction interpretive structural modeling lateral displacement

Modification of nanometer calcium carbonate for water-borne architectural coatings

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Journal of China University of Mining and Technology 2008年第1期18卷 76-81页

作者： WANG Xun-qiu jiang Deng-gao School of Chemical Engineering Zhengzhou University Zhengzhou Henan 450002 China

A kind of modifier was synthesized to modify the surface of nanometer calcium carbonate （abbreviated as nano-CaCO3）, which is used in architectural coatings. The modification technology of the nano-CaCO3 was studied through orthogonal experimental methods. The factors studied were rotation speed, modifier dosage, emulsification temperature, emulsification time and heat aging time after emulsification. Optimized conditions for modification of the surface were： rotation speed 16000 r/min; modifier dosage 3%; emulsification temperature 75 ℃; emulsification time 60 min and aging time 40 min. The modified nano-CaCO3 was also studied by size-distribution measurements, transmission electron microscopy, infrared spectroscopy and thermal analysis. The results show that the size distribution of the modified nano-CaCO3 is uniform and that there are chemi-sorption and physi-sorption between the nano-CaCO3 and the modifier. Compared to traditional architectural coatings without nano-CaCO3, the nanometer composite coatings are obviously improved in respect to dirt resistance, scrub resistance, thixotropy, water resistance, alkalinity resistance and aging resistance.

关键词： nanometer calcium carbonate surface modification modifier architectural coatings

Coordination-reduction leaching process of ion-adsorption type rare earth ore with ascorbic acid

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Journal of Rare Earths 2023年第8期41卷 1225-1233,I0004页

作者： Jinfa Chen jiang qiu Li Huang Xin Chen Ying Yang Yanfei Xiao Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China Ganzhou Engineering Technology Research Center of Green Metallurgy and Process Intensification Ganzhou 341000China Key Laboratory of Ionic Rare Earth Resources and Environment Ministry of Natural ResourcesGanzhou 341000China Key Laboratory of Testing and Tracing of Rare Earth Products for State Market Regulation Ganzhou 341000China

The magnesium sulfate(MgSO_(4))-ascorbic acid(Vc)compound leaching technique can extract rare earth elements(REEs)existing in ion-exchangeable phase and colloidal phase from ion-adso rption type rare earth ore through the synergy effect of coordination and reduction,but its reaction process and mechanism remain *** this paper,the coordination-reduction leaching mechanism was analyzed from the perspectives of leaching thermodynamics and kinetics,which provide theoretical guidance for the compound leaching *** the case of neodymium,about 45%of dissolved neodymium will exist as the complex species of NdVc_(()3(aq))in Nd-Vc-sulfate *** on this,it is deduced that the Gibbs free energy of the leaching reaction of ion-exchangeable phase REEs will change to a more negative value through the coordination of REEs cations and Vc anions in the MgSO_(4)leaching *** addition,the E_(h)-pH diagrams of Ce-SO_(4)^(2-)-H_(2)O and Fe-SO_(4)^(2-)-H_(2)O together with the dissolution experiments confirm that the added Vc initiates the leaching process of colloidal phase REEs through reduction-dissolution *** the study of leaching kinetics,the leaching of REEs is controlled by diffusion and chemical reaction in the co mpound leaching system since colloidal phase REEs are ***,the addition of Vc can shift the leaching equilibrium to a more favorable state and accelerate leaching *** rare earth leaching efficiency of ion-exchangeable phase and colloidal phase can be effectively improved by increasing the reaction temperature,the conce ntrations of leaching agent and Vc,and the leaching agent acidity.

关键词： Ion-adsorption type rare earth ore Ascorbic acid Coordination Reduction Leaching Mechanism

Electrifying the future:the advances and opportunities of electrocatalytic carbon dioxide reduction in acid

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Science China Chemistry 2023年第12期66卷 3426-3442页

作者： Runhao Zhang Haoyuan Wang Yuan Ji qiu jiang Tingting Zheng Chuan Xia Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China

Transforming carbon dioxide(CO_(2))into products using renewable electricity is a crucial and captivating quest for a green and circular *** with commonly used alkali electrolytes,acidic media for electrocatalytic CO_(2) reduction(CO_(2)RR)boasts several advantages,such as high carbon utilization efficiency,high overall energy utilization rate,and low carbonate formation,making it a compelling choice for industrial ***,the acidic CO_(2)RR also struggles with formidable hurdles,encompassing the fierce competition with the hydrogen evolution reaction,the low CO_(2) solubility and availability,and the suboptimal performance of *** review provides a comprehensive overview of the CO_(2)RR in acidic *** elucidating the underlying regulatory mechanism,we gain valuable insights into the fundamental principles governing the acidic CO_(2)***,we examine cutting-edge strategies aimed at optimizing its performance and the roles of reactor engineering,especially membrane electrode assembly reactors,in facilitating scalable and carbon efficient ***,we present a forward-looking perspective,highlighting the promising prospects of acidic CO_(2)RR research in ushering us towards a carbon-neutral society.

关键词： electrocatalytic CO_(2)reduction acidic electrolyte microenvironment alkali metal cations electrolysers

The time course of visual categorization:Electrophysiological evidence from ERP

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Chinese Science Bulletin 2006年第13期51卷 1586-1592页

作者： CHEN Antao LI Hong qiu jiang LUO Yuejia School of Psychology and MOE Key Laboratory of Cognition and Personality Southwest University Chongqing 400715 China State Key Laboratory of Cognitive Neuroscience and Learning Bei jing Normal University Beijing 100101 China Institute of Psychology Chinese Academy of Sciences Beijing 100875 China

Visual categorization can be derived from interaction between inputting features set (IFS) from outside stimuli and anticipating features set (AFS) from concept, and such interaction can take two forms: match extraction and conflict control. Us- ing ERP recording, we investigated the temporal course of visual categorization. The results indicated that the larger the AFS, the higher the amplitude of the N1 was generated, which demonstrated the effect of the AFS on the attention. When the size of the AFS was larger than or equal to 2, prominent N2 compo- nent was elicited, which demonstrated the effect of conflict when the feature of IFS mismatched with the feature of the AFS. The judgment of category was manifested on the LPC component, and this com- ponent was also sensitive to conflict control. Based on the results, we proposed that the temporal course of visual categorization was as follows: selective at- tention, feature perception, feature match/extraction and judgment of category/conflict control. Among those processes, the judgment of category is the core processing; however the former three sub-processes form the base of categorization. The results are in support of the idea that LPC is responsible for high- level categorization process.

关键词：视觉分类电生理学 ERP AFS IFS 冲突控制

Modeling of sensor function for piezoelectric bender elements

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第1期9卷 1-7页

作者： Yan-guo ZHOU Yun-min CHEN Hao-jiang DING Wei-qiu CHEN Key Laboratory of Soft Soils and Geoenvironmental Engineering Ministry of Education Zhejiang University Hangzhou 310027 China

An analytical sandwich beam model for piezoelectric bender elements is derived based on the first-order shear deformation theory (FSDT), which assumes a single rotation angle for the whole cross-section and a quadratic distribution for coupled electric potential in piezoelectric layers. Shear coefficient is introduced to correct the effect of transverse shear strain on shear force and the electric displacement integration. Static and free vibration analyses of simply-supported bender elements are carried out for the sensor function. The results illustrate the high accuracy of the present model compared with the exact 2D solutions.

关键词： Bender elements Piezoelectric Sensor Sandwich beam Shear coefficient

Application of machine learning algorithms for the evaluation of seismic soil liquefaction potential

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Frontiers of Structural and Civil Engineering 2021年第2期15卷 490-505页

作者： Mahmood AHMAD Xiao-Wei TANG jiang-Nan qiu Feezan AHMA Wen-Jing GU State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Department of Civil Engineering University of Engineering and Technology Peshawar(Bannu Campus)Bannu 28100Pakistan School of Economics&Management Dalian University of TechnologyDalian 116024China Department of Civil Engineering Abasyn UniversityPeshawar 25000Pakistan

This study investigates the performance of four machine learning(ML)algorithms to evaluate the earthquake-induced liquefaction potential of soil based on the cone penetration test field case history records using the Bayesian belief network(BBN)learning software *** BBN structures that were developed by ML algorithms-K2,hill climbing(HC),tree augmented naive(TAN)Bayes,and Tabu search were adopted to perform parameter learning in Netica,thereby fixing the BBN *** performance measure indexes,namely,overall accuracy(OA),precision,recall,F-measure,and area under the receiver operating characteristic curve,were used to evaluate the training and testing BBN models’performance and highlight the capability of the K2 and TAN Bayes models over the Tabu search and HC *** sensitivity analysis results showed that the cone tip resistance and vertical effective stress are the most sensitive factors,whereas the mean grain size is the least sensitive factor in the prediction of seismic soil liquefaction *** results of this study can provide theoretical support for researchers in selecting appropriate ML algorithms and improving the predictive performance of seismic soil liquefaction potential models.

关键词： seismic soil liquefaction Bayesian belief network cone penetration test parameter learning structural learning

A step forward towards a comprehensive framework for assessing liquefaction land damage vulnerability:Exploration from historical data

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Frontiers of Structural and Civil Engineering 2020年第6期14卷 1476-1491页

作者： Mahmood AHMAD Xiao-Wei TANG jiang-Nan qiu Feezan AHMAD Wen-Jing GU State Key Laboratory of Coastal and Ofishore Engineering Dalian University of TechnologyDalian 116024China Department of Civil Engineering University of Engineering and Technology Peshawar(Bannu Campus)Bannu 28100Pakistan School of Economics&Management Dalian University of TechnologyDalian 116024China Deparment of Civil Enginering Abasyn UniversitPeshawar 25000Pakistan

The unprecedented liquefaction-related land damage during earthquakes has highlighted the need to develop a model that better interprets the liquefaction land damage vulnerability(LLDV)when determining whether liquefaction is likely to cause damage at the ground's *** paper presents the development of a novel comprehensive framework based on select case history records of cone penetration tests using a Bayesian belief network(BBN)methodology to assess seismic soil liquefaction and liquefaction land damage potentials in one *** BBN-based LLDV model is developed by integrating multi-related factors of seismic soil liquefaction and its induced hazards using a machine learming(ML)algorithm-K2 and domain knowledge(DK)data fusion *** with the C4.5 decision tree-J48 model,naive Bayesian(NB)classifier,and BBN-K2 ML prediction methods in terms of overall accuracy and the Cohen's kappa coefficient,the proposed BBN K2 and DK model has a better performance and provides a substitutive novel LLDV framework for characterizing the vulnerability of land to liquefaction-induced *** proposed model not only predicts quantitatively the seismic soil liquefaction potential and its ground damage potential probability but can also identify the main reasons and fault-finding state combinations,and the results are likely to assist in decisions on seismic risk mitigation measures for sustainable *** proposed model is simple to perform in practice and provides a step toward a more sophisticated liquefaction risk assessment *** study also interprets the BBN model sensitivity analysis and most probable explanation of seismic soil liquefed sites based on an engineering point of view.

关键词： Bayesian belief network liquefaction-induced damage potential cone penetration test soil liquefaction structural leaming and domain knowledge