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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)elements.In the leaching process for recovering rare earth elements from IATREOs,many impurities will be leached together with rare earth elements and enter the leaching liquor.An 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 industry.However,a high loss of rare earth elements and severe ammonia nitrogen pollution are caused by this process.Therefore,more beneficial impurities removal technologies,mainly for aluminum,and green enrichment technologies with lower pollution are now urgently needed.For 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 elements.Finally,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

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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 unclear.In 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 process.In the case of neodymium,about 45%of dissolved neodymium will exist as the complex species of NdVc_(()3(aq))in Nd-Vc-sulfate system.Based 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 process.In 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 reaction.Through 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 leached.Therefore,the addition of Vc can shift the leaching equilibrium to a more favorable state and accelerate leaching process.The 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

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Insight into leaching of rare earth and aluminum from ion adsorption type rare earth ore:Adsorption and desorption

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稀土学报:英文版 2023年第9期41卷 1398-1407,I0005页

作者： Qiang He jinfa chen Limei Gan Menglan Gao 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 Key Laboratory of Ionic Rare Earth Resources and Environment Ministry of Natural ResourcesGanzhou 341oooChina Key Laboratory of Testing and Tracing of Rare Earth Products for State Market Regulation Ganzhou 34100oChina

Clay minerals are inferred to be the primary host materials for ion-exchangeable rare earth in ion adsorption type rare earth ore(IAREO).During the rare earth leaching process,the adsorption and desorption reactions of the cations controlling the leaching process continue to occur at the clay minerals-leaching agent solution interface.In order to understand the leaching mechanism and behavior of rare earth and co-leached aluminum,adsorption,competitive adsorption,and desorption experiments were carried out using kaolin as a typical clay mineral.The powerful electrostatic attraction and concentration driving forces facilitate the adsorption of cations.The adsorption ability and competitive adsorption ability of cations depend on their charge,hydration radius,and hydrolysis properties,and decrease in the order of La^(3+),Y^(3+),Al^(3+),Mg^(2+),and NH_(4)^(+).The desorption of rare earth and aluminum is positively affected by the concentration-driving force exerted by high concentrations of Mg^(2+) and NH_(4)^(+),with the order of the desorption ability being opposite to the adsorption ability.However,unspecified interactions between clay mineral particles enhanced by high-concentration desorbents,especially by Mg^(2+) than NH_(4)^(+),will adversely affect desorption reactions,which result in lower desorption efficiencies of rare earth and aluminum obtained with magnesium sulfate compared to those obtained with ammonium sulfate at high concentrations.Solid-phase Al(OH)_(3) generated at a high peak aluminum concentration leads to a considerably delayed aluminum efflux,thereby partially separating the rare earth from aluminum during the actual column leaching process.To advance the mining technology of IAREO by selectively improving the rare earth leaching efficiency with minimal leaching agent consumption,higher charged cations with concentrations limited to suitable levels should be preferred as leaching agents.

关键词： Rare earths Aluminum Kaolin Adsorption Desorption

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Biosorption of Cr（VI） by carbonized Eupatorium adenophorum and Buckwheat straw： thermodynamics and mechanism

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Frontiers of Environmental Science & Engineering 2014年第6期8卷 960-966页

作者： jinfa chen Ping YANG Dagang SONG Sha YANG Li ZHOU Lei HAN Bo LAI Department of Agricultural Science Xichang College Xichang 615013 China College of Architecture & Environment Sichuan University Chengdu 610065 China

High quality and low cost carbon can be prepared from Eupatorium adenophorum （E. adenophorum） and Buckwheat straw. The biosorbent was used for Cr（VI） removal. The effect of experimental parameters, such as pH, sorbent dosage and temperature were examined and the optimal experimental condition was determned. Solution pH is found influencing the adsorp- tion. Cr（VI） removal efficiency is found to be maximum （98%） at pH= 1. Langmuir and Freundlich adsorption isotherms were applicable to the adsorption process and their constants were evaluated. The adsorption data obtained agreed well with the Langmuir sorption isotherm model. The maximum adsorption capacities for Cr（VI） ranged from 46.23 to 55.19mg.g^-1 for temperature between 298 K and 308 K under the condition of pH = 1.0. Thermodynamic parameters such as free energy change （AG）, enthalpy （AH） and entropy （AS） indicate a spontaneous, endothermic and increased randomness nature of Cr（VI） adsorption. Studies found that the raw E. adenophorum and buckwheat straw mixed materials with simple treatment had a high efficiency for the removal of Cr（VI） and would be a promising adsorbent.

关键词： Eupatorium adenophorum buckwheat straw adsorption Cr（VI） thermodynamics

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二氧化碳碳化沉淀制备碳酸钇的反应过程研究

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中国稀土学报 2024年第1期42卷 90-101,I0003页

作者：陈金发赖安邦何志宏昝苗苗卢颖肖燕飞江西理工大学材料冶金化学学部赣州市绿色冶金与过程强化工程技术研究中心自然资源部离子型稀土资源与环境重点实验室稀土产品检测与溯源国家市场监管重点实验室江西赣州341000

CO_(2)碳化沉淀制备特殊物性金属化合物粉体具有成本低、操作简单等优点,已成功应用于纳米、大比表面稀土氧化物的制备。以Y元素为研究对象,针对酸/碱体系下CO_(2)碳化沉淀制备碳酸钇的反应过程进行研究。结果表明,氯化钇的引入会迅速与... 详细信息

CO_(2)碳化沉淀制备特殊物性金属化合物粉体具有成本低、操作简单等优点,已成功应用于纳米、大比表面稀土氧化物的制备。以Y元素为研究对象,针对酸/碱体系下CO_(2)碳化沉淀制备碳酸钇的反应过程进行研究。结果表明,氯化钇的引入会迅速与H_(2)CO_(3)-H_(2)O体系中的HCO_(3)^(-)离子反应生成Y_(2)(CO_(3))_(3)·xH_(2)O,从而促进H_(2)CO_(3)的电离,导致pH小于9.0的溶液中HCO_(3)^(-)的占比小于1%。在酸性体系下,CO_(2)首先发生溶解吸收电离,然后Y^(3+)与HCO_(3)^(-)反应进行沉淀,而NaOH的加入中和了反应释放出的H^(+),从而控制碳化体系pH;整个碳化过程符合一级反应动力学模型,由传质扩散和化学反应混合控制。在碱性体系下,Y(OH)_(3)的转化率随着CO_(2)通入迅速增加,然后由于碳酸钇对Y(OH)_(3)的包裹钝化而趋于平稳,进而Y(OH)_(3)结构坍塌碳化转化率急剧增加至完全转化。而在酸碱不同体系中,温度越高,均更易形成均相沉淀体系,有利于碳酸钇的晶型生长,获得结晶性能良好的Y_(2)(CO_(3))_(3)·2H_(2)O。本文的研究强化了对CO_(2)碳化沉淀碳酸钇反应过程的认识,有利于指导特殊物性稀土氧化物的均相可控及高效制备。

关键词：二氧化碳碳化碳酸钇反应过程物种分布

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高速铁路接触网弹性吊索疲劳仿真研究

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振动与冲击 2024年第12期43卷 9-16,29页

作者：刘继冬陈俊卿关金发韩峰吴积钦西南交通大学电气工程学院成都611756

为研究弹性吊索的服役状态与疲劳寿命,对高铁接触网出现的弹性吊索断线现象进行调研并开展疲劳研究。基于武广高铁的线路设计参数构建了弓网动态仿真模型,对300 km/h速度下的弹性吊索振动状态进行分析。由于受电弓运行通过时对接触悬挂... 详细信息

为研究弹性吊索的服役状态与疲劳寿命,对高铁接触网出现的弹性吊索断线现象进行调研并开展疲劳研究。基于武广高铁的线路设计参数构建了弓网动态仿真模型,对300 km/h速度下的弹性吊索振动状态进行分析。由于受电弓运行通过时对接触悬挂的抬升作用,弹性吊索主要沿竖直方向振动,并在线夹位置不断承受交变弯曲载荷。在UG软件中建立了弹性吊索绞线(1×7)及其线夹的实体模型并将其导入到LS-DYNA软件中进行了应力载荷计算;其应力集中位置位于弹性吊索与其线夹连接处。将应力历程数据导入到ANSYS nCode DesignLife软件中分析弹性吊索在指定载荷下的疲劳寿命。最后,根据Miner累积损伤原则计算了300 km/h运行速度下武广高铁弹性吊索的疲劳寿命为4.58×10^(6)弓架次;当运行速度增加至350 km/h时,疲劳寿命为1.17×10^(6)弓架次;当运行速度增加至400 km/h时,疲劳寿命为4.80×10^(5)弓架次。

关键词：高速铁路接触网弹性吊索应力载荷疲劳仿真

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产前诊断的先天性十二指肠梗阻胎儿出生后的临床特点及治疗

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中华小儿外科杂志 2024年第4期45卷 329-333页

作者：王林燕陈益薛佳金钱云忠钭金法高志刚陈青江浙江大学医学院附属儿童医院普外科国家儿童健康与疾病临床医学研究中心浙江省腹腔脏器微创诊治临床医学研究中心杭州310052

目的总结产前诊断的先天性十二指肠梗阻胎儿出生后的临床特点及治疗经验。方法回顾性分析2011年1月至2020年12月浙江大学医学院附属儿童医院收治的产前诊断为十二指肠梗阻且出生后接受手术治疗的105例患儿临床资料,其中男48例,女57例;... 详细信息

目的总结产前诊断的先天性十二指肠梗阻胎儿出生后的临床特点及治疗经验。方法回顾性分析2011年1月至2020年12月浙江大学医学院附属儿童医院收治的产前诊断为十二指肠梗阻且出生后接受手术治疗的105例患儿临床资料,其中男48例,女57例;首次诊断胎龄在15~39周,出生时胎龄为31^(+1)~42周;患儿出生时体重为(2746.9±608.6)g;早产38例;入院时患儿中位年龄为9 h,范围在1 h至21 d。出生后患儿呕吐40例,其中未开奶26例,开奶14例。伴发其他系统畸形80例,其中先天性心脏病69例,36例患儿合并2种及2种以上畸形。所有患儿均接受手术治疗,术中证实患儿病理类型,术后记录患儿开始进食时间、术后住院时间,观察患儿并发症情况。结果105例患儿手术均成功完成,其中开腹手术23例,腹腔镜手术80例(中转开腹2例),机器人辅助2例。术中发现病理类型包括环状胰腺78例,十二指肠闭锁15例,十二指肠狭窄10例,肠旋转不良13例,十二指肠前门静脉2例,空肠起始部闭锁1例;其中14例患儿同时存在2处或2处以上梗阻。术后开始进食时间(7.64±3.28)d,术后住院时间(16.66±9.12)d。术后出现并发症3例,其中1例吻合口漏及1例肠梗阻患儿,经保守治疗后好转;另1例十二指肠远端闭锁及空肠近端Ⅲ型闭锁术后吻合口狭窄,再次行肠切除肠吻合联合十二指肠成形术后好转。结论产前诊断的先天性十二指肠梗阻胎儿出生后就诊及治疗时间提前,出生后应禁食及胃肠减压,早期手术治疗后预后良好。环状胰腺为最常见的病理类型。通常伴发合并其他系统畸形,产前需重点筛查染色体及心脏。

关键词：十二指肠梗阻产前诊断新生儿病理腹腔镜手术

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Expression and possible role of Smad3 in postnecrotizing enterocolitis stricture

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World Journal of Pediatric Surgery 2022年第1期5卷 30-39页

作者： Rui chen chengjie Lv Xiaoxia Zhao Dong Ma Dengming Lai Yun Zhao Luyin Zhang jinfa Tou Department of Neonatal Surgery Zhejiang University School of Medicine Children's HospitalHangzhouPeople's Republic of China National Center for clinical medicine of children's health and disease HangzhouPeople's Republic of China Department of Pathology Zhejiang University School of Medicine Children's HospitalHangzhouPeople's Republic of China Pediatric Surgery Affiliated Hangzhou First People's HospitalZhejiang University School of MedicineHangzhouPeople's Republic of China

Objective To investigate the expression of Smad3(mothers against decapentaplegic homolog 3)protein in postnecrotizing enterocolitis stricture and its possible mechanism of action.Methods We used immunohistochemistry to detect the expression characteristics of Smad3 and nuclear factor kappa B(NF-κB)proteins in human postnecrotizing enterocolitis stricture.We cultured IEC-6(crypt epithelial cells of rat small intestine)in vitro and inhibited the expression of Smad3 using siRNA technique.Quantitative PCR,western blotting,and ELISA were used to detect the changes in transforming growth factor-β1(TGF-β1),NF-κB,tumor necrosis factor-α(TNF-α),vascular endothelial growth factor(VEGF),and zonula occludens-1(ZO-1)messenger RNA(mRNA)and protein expressions in IEC-6 cells.CCK8 kit and Transwell cellular migration were used to detect cell proliferation and migration.Changes in epithelial-mesenchymal transition(EMT)markers(E-cadherin and vimentin)in IEC-6 cells were detected by immunofluorescence technique.Results The results showed that Smad3 protein and NF-κB protein were overexpressed in narrow intestinal tissues and that Smad3 protein expression was positively correlated with NF-κB protein expression.After inhibiting the expression of Smad3 in IEC-6 cells,the mRNA expressions of NF-κB,TGF-β1,ZO-1,and VEGF decreased,whereas the mRNA expression of TNF-αdid not significantly change.TGF-β1,NF-κB,and TNF-αprotein expressions in IEC-6 cells decreased,whereas ZO-1 and intracellular VEGF protein expressions increased.IEC-6 cell proliferation and migration capacity decreased.There was no significant change in protein expression levels of EMT markers E-cadherin and vimentin and also extracellular VEGF protein expression.Conclusions We suspect that the high expression of Smad3 protein in postnecrotizing enterocolitis stricture may promote the occurrence and development of secondary intestinal stenosis.The mechanism may be related to the regulation of TGF-β1,NF-κB,TNF-α,ZO-1,and VEGF mRNA and protein expression.This may also be relate

关键词： Smad3 expression. stricture

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基于七情配伍理论的补骨脂药对配伍规律研究进展

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中国药物警戒 2024年第5期21卷 594-600页

作者：王晓艳陈小菲张辉张明亮吴娅丽杨柳青唐进法李伟霞河南中医药大学第一附属医院药学部河南郑州450000 河南省中药临床应用、评价与转化工程研究中心河南郑州450000 河南省中药临床药学中医药重点实验室河南郑州450000 河南省中药安全评价与风险防控工程研究中心河南郑州450000

目的基于中药七情配伍理论归纳补骨脂药对配伍规律,为补骨脂临床合理应用提供依据。方法通过古籍与现代文献检索与分析,从相须相使、协同增效、相畏相杀、减毒降副,配伍禁忌三方面总结补骨脂配伍规律。结果基于七情配伍理论探析补骨... 详细信息

目的基于中药七情配伍理论归纳补骨脂药对配伍规律,为补骨脂临床合理应用提供依据。方法通过古籍与现代文献检索与分析,从相须相使、协同增效、相畏相杀、减毒降副,配伍禁忌三方面总结补骨脂配伍规律。结果基于七情配伍理论探析补骨脂药对的配伍规律,补骨脂常用相须相使药对为肉豆蔻、蛇床子、小茴香、益智仁、肉桂、吴茱萸、巴戟天、杜仲、骨碎补、仙茅,常用相畏相杀药对为胡桃仁、生地黄、五味子、赤芍,相恶、相反禁忌药对有甘草、淫羊藿。结论总结了常与补骨脂配伍的药对,为临床遣方用药提供思路。

关键词：中药七情配伍药对补骨脂增效减毒整体观念

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Nanoparticle-mediated corneal neovascularization treatments: Toward new generation of drug delivery systems

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Chinese Chemical Letters 2023年第3期34卷 90-99页

作者： Huimin Zhu Jingwen Yu jinfa Ye Yiming Wu Jintao Pan Yingying Li Chuan chen Li Zheng Gang Liu chengchao Chu Collaborative Innovation Centre of Regenerative Medicine and Medical BioResource Development and Application Co-Constructed by the Province and Ministry Guangxi Medical UniversityNanning 530021China Eye Institute of Xiamen University Fujian Provincial Key Laboratory of Ophthalmology and Visual ScienceXiamen UniversityXiamen 361102China State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics and Center for Molecular Imaging and Translational Medicine School of Public Health Xiamen Xiamen UniversityXiamen 361102China Department of Pharmacy Xiamen Medical CollegeXiamen 361023China Shenzhen Research Institute of Xiamen University Shenzhen 518057China

Corneal neovascularization(CNV) is one of the major factors for vision impairment and blindness worldwide. The current treatment for CNV focuses primarily on topical eyedrops of glucocorticoids,non-steroidal anti-inflammatory drugs, electro-coagulation and laser photo-coagulation. Unfortunately,coagulation-based treatment is restricted by corneal hemorrhage and iris atrophy. And drug treatments have limited therapeutic effects and a short duration of action. Nanoparticle-based drug delivery systems are widely applied due to their improved pharmacokinetics, optimized drug targeting and enhanced biocompatibility. In this article, we provide a comprehensive and systematic overview of the CNV nanodrug system, highlighting some of the recent advances in nanodrug design, preparation, and functional modification. Moreover, we discuss the challenges in the clinical translation and potential risks in CNV treatment. A greater effort is needed for the potential applications of nanotechnology in the field of ophthalmology.

关键词： Corneal neovascularization Nanoparticles Drug delivery system Anti-VEGF Supramolecular assembly

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