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Geochemical characteristics and source analysis of rare earth elements in Qinghai Lake sediments
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作者 Guangying Li Yingyi Meng +3 位作者 Jinhan Zhou Di Ming Lijun Dai Lingqing Wang 《Acta Geochimica》 2025年第2期231-246,共16页
This study investigates the distribution,geochemical behavior,and potential anthropogenic influences of rare earth elements(REEs)in the surface sediments of Qinghai Lake,the largest saline lake in China.A total of 36 ... This study investigates the distribution,geochemical behavior,and potential anthropogenic influences of rare earth elements(REEs)in the surface sediments of Qinghai Lake,the largest saline lake in China.A total of 36 surface sediment samples were analyzed for REE concentrations with a combination of self-organizing maps(SOM)and positive matrix factorization(PMF).Results indicate distinct enrichment patterns,with light REEs(LREEs)exhibiting higher concentrations than heavy REEs(HREEs),reflecting natural abundances and geochemical behaviors.The minimum value was found in Lu as low as 0.091 mg/kg,and the maximum concentration was exhibited in Ce at 78.877 mg/kg.Geoaccumulation index(I_(geo))analysis reveals minor to moderate enrichment of specific REEs of Sm and Nd,suggesting possible localized anthropogenic inputs,particularly near river mouths.Spatial analysis using inverse distance weighting(IDW)and self-organizing maps(SOM)highlights significant correlations between REE distributions and riverine inputs,underscoring fluvial transport's role in sedimentary REE dynamics.PMF identifies mixed natural and anthropogenic sources,with agricultural and industrial activities contributing to elevated REE levels in sediment.These findings provide critical insights into the geochemical behavior of REEs in saline lake systems and off er a foundation for pollution control and sustainable resource management in sensitive environments like Qinghai Lake. 展开更多
关键词 rare earth elements Qinghai Lake SEDIMENTS Anthropogenic impact SOURCES
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The Electrocatalytic Performance of Rare Earth Ion Doped Co_(0.2)Ni_(0.8)-MOF-74 Catalyst for Nitrogen Reduction
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作者 YUE Song GONG Lunjun +4 位作者 YANG Tonghui HU Weida LIU Xiaopan GAO Pengzhao XIAO Hanning 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1337-1347,共11页
We took Co_(0.2)Ni_(0.8)-MOF-74 with bimetallic synergistic effect as the basic material,and selected rare earth ions Ho,Gd,and Er with ion radii close to Co and Ni as the research objects for doping.The influence of ... We took Co_(0.2)Ni_(0.8)-MOF-74 with bimetallic synergistic effect as the basic material,and selected rare earth ions Ho,Gd,and Er with ion radii close to Co and Ni as the research objects for doping.The influence of rare earth ion doping amount and doping type on the eNRR performance of the catalyst was explored.The experimental results show that the ammonia yield rate and Faraday efficiency doped with Co_(0.2)Ni_(0.8)-MOF-0.5Ho are the highest,reaching 1.28×10^(-10)mol·s^(-1)·cm^(-2)/39.8%,which is higher than the1.12×10^(-10)mol·s^(-1)·cm^(-2)/32.2%of Co_(0.2)Ni_(0.8)-MOF-74,and is about 14.3%/23.7%higher than that without doping,respectively.And the stability of Co_(0.2)Ni_(0.8)-MOF-0.5 Ho is good(after 80 hours of continuous testing,the current density did not significantly decrease).This is mainly due to doping,which gives Co_(0.2)Ni_(0.8)-MOF-74 a larger specific surface area and catalytic active sites.The catalyst doped at the same time has more metal cation centers,which increases the electron density of the metal centers and enhances the corresponding eNRR performance. 展开更多
关键词 electrocatalytic nitrogen reduction metal organic framework rare earth ions DOPING
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Effect and Mechanism of Rare Earth Hydrotalcite Inhibiting Coal Spontaneous Combustion
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作者 张小娟 LIU Bo +1 位作者 罗振敏 SUN Lu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期50-59,共10页
A hydrotalcite(layered double hydroxide, LDH) inhibitor which is suitable for the whole process of coal spontaneous combustion and a LDH inhibitor containing rare earth lanthanum elements were prepared. The inhibition... A hydrotalcite(layered double hydroxide, LDH) inhibitor which is suitable for the whole process of coal spontaneous combustion and a LDH inhibitor containing rare earth lanthanum elements were prepared. The inhibition effect and mechanism were analyzed by scanning electron microscopy(SEM),X-ray diffraction(XRD), thermal performance analysis, in-situ diffuse reflectance infrared spectroscopy and temperature-programmed experiment. The results have shown that the inhibitor containing lanthanum can play a good inhibitory role in every stage of coal oxidation. During the slow oxidation of coal samples, the inhibitor containing lanthanum ions can slow down the oxidation process of coal and increase the initial temperature of coal spontaneous combustion. At the same time, because the hydroxyl groups in LDHs are connected with-COO-groups on the coal surface through hydrogen bonds, the stability of coal is improved. With the increase of temperature, LDHs can remove interlayer water molecules and reduce the surface temperature of coal. CO release rate of coal samples decreases significantly after adding inhibitor containing lanthanum element, and the maximum inhibition rate of the inhibitor is 58.1%. 展开更多
关键词 rare earth HYDROTALCITE coal spontaneous combustion MECHANISM
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Rare Earth Elements(La,Ce,Pr)Modified Co/NC Catalyst for Efficient and Stable Ammonia Decomposition to Hydrogen Production
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作者 ZHU Yi PAN Hongfei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1372-1378,共7页
Co/NC catalysts modified with rare earth elements(La,Ce,Pr)were prepared by pyrolysis of rare earth elements doped ZIF-67.The experimental results show that the modification of rare earth elements significantly improv... Co/NC catalysts modified with rare earth elements(La,Ce,Pr)were prepared by pyrolysis of rare earth elements doped ZIF-67.The experimental results show that the modification of rare earth elements significantly improves the ammonia decomposition activity and stability of the Co/NC catalyst.The La-Co/NC catalyst can achieve an 82.3%ammonia decomposition and 18.4 mmol hydrogen production rate at 550℃with a GHSV of 20000 cm^(3)·h^(-1).Furthermore,no obvious performance degradation is observed after 72 hours of reaction for all rare earth elements modified catalysts.It is shown that the modification of rare earth elements significantly improves the surface alkalinity and surface chemical state of the catalyst,and thus improves the ammonia decomposition activity of the catalyst.A new type of high-performance ammonia decomposition Co-based catalyst is proposed,and the promoting effect of rare earth elements on the activity of ammonia decomposition is revealed. 展开更多
关键词 hydrogen carrier hydrogen production ammonia decomposition rare earth elements cobalt-based catalysts
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Association between Exposure of Rare Earth Elements and Outcomes of In Vitro Fertilization-Embryo Transfer in Beijing
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作者 Yutong Wang Jing Li +9 位作者 Shirong Xu Shengli Lin Zhenchen Hou Linlin Wang Yali Huang Yue Sun Wei Guo Lailai Yan Ying Wang Chan Tian 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第8期876-886,共11页
Objective The study aimed to investigate the impact of rare earth elements(REEs)exposure on pregnancy outcomes of in vitro fertilization-embryo transfer(IVF-ET)by analyzing samples from spouses.Methods A total of 141 ... Objective The study aimed to investigate the impact of rare earth elements(REEs)exposure on pregnancy outcomes of in vitro fertilization-embryo transfer(IVF-ET)by analyzing samples from spouses.Methods A total of 141 couples were included.Blood and follicular fluid from the wives and semen plasma from the husbands,were analyzed for REEs using inductively coupled plasma mass spectrometry(ICP-MS).Spearman's correlation coefficients and the Mann–Whitney U test were used to assess correlations and compare REE concentrations among three types of samples,respectively.Logistic models were utilized to estimate the individual REE effect on IVF-ET outcomes,while BKMR and WQS models explored the mixture of REE interaction effects on IVF-ET outcomes.Results Higher La concentration in semen(median 0.089 ng/mL,P=0.03)was associated with a lower fertilization rate.However,this effect was not observed after artificial selection intervention through intracytoplasmic sperm injection(ICSI)(P=0.27).In semen,the REEs mixture did not exhibit any significant association with clinical pregnancy.Conclusion Our study revealed a potential association between high La exposure in semen and a decline in fertilization rate,but not clinical pregnancy rate.This is the first to report REEs concentrations in follicular fluid with La,Ce,Pr,and Nd found at significantly lower concentrations than in serum,suggesting that these four REEs may not accumulate in the female reproductive system.However,at the current exposure levels,mixed REEs exposure did not exhibit reproductive toxicity. 展开更多
关键词 rare earth elements In vitro fertilization Pregnancy outcomes Mixture exposure analysis
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Improvement strategy on thermophysical properties of A_(2)B_(2)O_(7)-type rare earth zirconates for thermal barrier coatings applications:A review
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作者 Zijian Peng Yuhao Wang +8 位作者 Shuqi Wang Junteng Yao Qingyuan Zhao Enyu Xie Guoliang Chen Zhigang Wang Zhanguo Liu Yaming Wang Jiahu Ouyang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期1147-1165,共19页
The A_(2)B_(2)O_(7)-type rare earth zirconate compounds have been considered as promising candidates for thermal barrier coating(TBC) materials because of their low sintering rate,improved phase stability,and reduced ... The A_(2)B_(2)O_(7)-type rare earth zirconate compounds have been considered as promising candidates for thermal barrier coating(TBC) materials because of their low sintering rate,improved phase stability,and reduced thermal conductivity in contrast with the currently used yttria-partially stabilized zirconia (YSZ) in high operating temperature environments.This review summarizes the recent progress on rare earth zirconates for TBCs that insulate high-temperature gas from hot-section components in gas turbines.Based on the first principles,molecular dynamics,and new data-driven calculation approaches,doping and high-entropy strategies have now been adopted in advanced TBC materials design.In this paper,the solid-state heat transfer mechanism of TBCs is explained from two aspects,including heat conduction over the full operating temperature range and thermal radiation at medium and high temperature.This paper also provides new insights into design considerations of adaptive TBC materials,and the challenges and potential breakthroughs are further highlighted for extreme environmental applications.Strategies for improving thermophysical performance are proposed in two approaches:defect engineering and material compositing. 展开更多
关键词 rare earth zirconates thermal barrier coatings defect engineering doping and compositing thermal conductivity thermal expansion
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Wetting front migration model of ion-adsorption rare earth during the multi-hole unsaturated liquid injection
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作者 Yu Wang Xiaojun Wang +8 位作者 Yuchen Qiu Hao Wang Gang Li Kaijian Hu Wen Zhong Zhongqun Guo Bing Li Chunlei Zhang Guangxiang Ye 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期483-496,共14页
In the process of ion-adsorption rare earth ore leaching,the migration characteristics of the wetting front in multi-hole injection holes and the influence of wetting front intersection effect on the migration distanc... In the process of ion-adsorption rare earth ore leaching,the migration characteristics of the wetting front in multi-hole injection holes and the influence of wetting front intersection effect on the migration distance of wetting fronts are still unclear.Besides,wetting front migration distance and leaching time are usually required to optimize the leaching process.In this study,wetting front migration tests of ionadsorption rare earth ores during the multi-hole fluid injection(the spacing between injection holes was 10 cm,12 cm and 14 cm)and single-hole fluid injection were completed under the constant water head height.At the pre-intersection stage,the wetting front migration laws of ion-adsorption rare earth ores during the multi-hole fluid injection and single-hole fluid injection were identical.At the postintersection stage,the intersection accelerated the wetting front migration.By using the Darcy’s law,the intersection effect of wetting fronts during the multi-hole liquid injection was transformed into the water head height directly above the intersection.Finally,based on the Green-Ampt model,a wetting front migration model of ion-adsorption rare earth ores during the multi-hole unsaturated liquid injection was established.Error analysis results showed that the proposed model can accurately simulate the infiltration process under experimental conditions.The research results enrich the infiltration law and theory of ion-adsorption rare earth ores during the multi-hole liquid injection,and this study provides a scientific basis for optimizing the liquid injection well pattern parameters of ion-adsorption rare earth in situ leaching in the future. 展开更多
关键词 ion-adsorption rare earth ore Multi-hole unsaturated liquid injection In situ leaching Intersection effect Calculation model
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Formation mechanism of electroless plating nickel-based composite coating on highly active rare earth magnesium alloys and its corrosion resistance and adhesion performance
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作者 WANG Bo LI Jia-wei +3 位作者 XIE Zhi-hui LIU Kang XU Tao YU Gang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第10期3517-3531,共15页
The process of preparing anodic oxide film containing active sites and electroless nickel plating on highly active rare earth magnesium alloy was developed.The formation mechanism of electroless nickel plating on acti... The process of preparing anodic oxide film containing active sites and electroless nickel plating on highly active rare earth magnesium alloy was developed.The formation mechanism of electroless nickel plating on active anodic oxide film and the structure and properties of the composite coating were studied by several surface and electrochemical techniques.The results showed that Ag nanograins with an average size of 10 nm were embedded into the anodic oxide film with pores of 0.1−2μm.Ag nanoparticles provided a catalytic site for the deposition of Ni-B alloy,and the Ni crystal nucleus was first grown in horizontal mode and then in cylindrical mode.The corrosion potential of the composite coating increased by 1.37 V and the corrosion current reduced two orders of magnitude due to the subsequent deposition of Ni-P alloy.The high corrosion resistance was attributed to the misaligning of these micro defects in the three different layers and the amorphous structure of the Ni-P alloy in the outer layer.These findings provide a new idea for electroless nickel plating on anodic oxide film. 展开更多
关键词 rare earth magnesium alloy electroless nickel plating composite coating Ag+activation active anodic oxidation film growth mechanism
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Differential Expression Analysis of Proteins Regulated by Rare Earth Cerium in Soybean Leaves at Seedling Stage
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作者 Ren Hongyu Zhang Tianren +3 位作者 Miao Yanli Li Haoyang Zhang Shuying Zhang Xingwen 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期42-52,共11页
This study was to explore the functional mechanism of rare earth regulating soybean leaves and the characteristics and functions of differentially expressed proteins under the regulation of rare earth. In this study, ... This study was to explore the functional mechanism of rare earth regulating soybean leaves and the characteristics and functions of differentially expressed proteins under the regulation of rare earth. In this study, Dongnong 42 was used as material, and 30 mg·L^(-1) CeCl_(3) solution was sprayed on soybean leaves at the seedling stage. Tandem mass tag(TMT) quantitative proteomics technique and bioinformatics analysis were used to identify soybean leaf proteins. A total of 8 510 proteins were identified, and 127 differentially expressed proteins(DEPs) in response to rare earth cerium regulation were identified, among which 64 were upregulated and 63 were down-regulated. The gene ontology(GO) annotation indicated that DEPs were mainly involved in metabolic process, cellular process, response to stimulus, biological regulation, and response to a stimulus;DEPs in cell module categories were mainly involved in cells, cell part, organelle, membrane, membrane part, organelle par, and protein-containing complex;DEPs in molecular functional categories were mainly involved in catalytic activity, binding and antioxidant activity. Kyoto encyclopedia of genes and genomes(KEGG) pathway significantly enriched starch and sucrose metabolism, glycolysis/gluconeogenesis, galactose metabolism, pentose phosphate pathway, and MAPK signaling pathway-plant. These DEPs were mainly involved in photosynthesis, glucose metabolism and stress response. Forty-six differential protein interaction networks were identified by protein interaction network analysis. This experiment provided a reference for studies of the mechanism of rare earth cerium regulating soybean leaf function from the proteomic perspective. 展开更多
关键词 rare earth soybean PROTEOMICS tandem mass tag(TMT)
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Top 11 countries by rare earth metal production
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作者 Melissa Pistilli 《China Rare Earth Information》 2024年第3期17-21,共5页
(Updated 2024)Rare earth metal production was on the rise again in 2023,jumping to 350,000 metric tons(MT)worldwide—that's up significantly from 190,000 MT in 2018,just five years prior.Demand for rare earth meta... (Updated 2024)Rare earth metal production was on the rise again in 2023,jumping to 350,000 metric tons(MT)worldwide—that's up significantly from 190,000 MT in 2018,just five years prior.Demand for rare earth metals is increasing as renewable energy becomes more important across the globe.Rare earths such as neodymium and praseodymium,which are important in clean energy applications and high-tech industries,are in the spotlight,particularly as electric vehicles and hybrid cars gain further popularity.With that in mind,it's worth being aware of rare earth metal production by country figures.Here's a look at the 11 countries that mined the most rare earths in 2023,as per the latest data from US Geological Survey(USGS). 展开更多
关键词 rare NEODYMIUM earth
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Disorganizing rare earth ions may improve quantum infor mation storage
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《China Rare Earth Information》 2024年第1期30-31,共2页
A new paper in Nature Physics shows that by cramming lots of rare earth ions into a crystal,some will form pairs that act as highly coherent qubits,thus debunking the idea that solid-state qubits need to be super dilu... A new paper in Nature Physics shows that by cramming lots of rare earth ions into a crystal,some will form pairs that act as highly coherent qubits,thus debunking the idea that solid-state qubits need to be super dilute in an ultra-clean material to achieve long lifetimes.According to the study's authors,one of the major barriers to practical quantum computing has been how to make qubits that retain their quantum information long enough to be useful. 展开更多
关键词 QUANTUM rare earth
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Effects of Biogas Slurry Application Years on Remediation of Pennisetum×sinese on Soil Physical and Chemical Properties and Microorganisms of Rare Earth Tailings
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作者 Shiyi FU Zhimei WANG +3 位作者 Wei LOU Zhiyong WU Sha LUO Guorong NI 《Agricultural Biotechnology》 2024年第6期22-27,33,共7页
[Objectives]This study was conducted to analyze the effects of continuous application of biogas slurry for many years on soil ecosystem restoration of rare earth tailings by planting Pennisetum×sinese,in order to... [Objectives]This study was conducted to analyze the effects of continuous application of biogas slurry for many years on soil ecosystem restoration of rare earth tailings by planting Pennisetum×sinese,in order to provide basis for scientific application of biogas slurry.[Methods]The fields with different years of continuous application of biogas slurry in Dingnan Rare Earth Tailings Ecological Restoration Demonstration Park were selected as the research object,and the differences in soil physical and chemical properties and microbial community structure after application of biogas slurry for different years(0,3 and 5 years)were studied.[Results]The bulk density of soil with continuous application of biogas slurry showed a downward trend,while the maximum water holding capacity,capillary water holding capacity,porosity,aeration,pH,organic matter,nitrogen,phosphorus and potassium,alkali-hydrolyzable nitrogen and available phosphorus showed an upward trend.Moreover,the effects achieved by application for 5 years were better than those by application for 3 years.Continuous application of biogas slurry could significantly improve the activity of soil urease,acid phosphatase,sucrase and cellulase,and it effects increased with the application year increasing.Continuous application of biogas slurry could significantly improve the abundance of dominant bacteria in soil,and with the increase of application years,the abundances of dominant bacteria also increased.[Conclusions]Continuous application of biogas slurry effectively improved soil physical and chemical properties and soil fertility in rare earth tailings areas where Pennisetum×sinese was planted to restore rare earth tailings.This study provides a theoretical support for establishing key ecological restoration technoiques. 展开更多
关键词 Biogas slurry Application period rare earth tailings Soil physical and chemical properties Soil microorganism
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Leaching characteristics of ion-adsorption type rare earths ore with magnesium sulfate 被引量:31
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作者 肖燕飞 陈迎迎 +4 位作者 冯宗玉 黄小卫 黄莉 龙志奇 崔大立 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第11期3784-3790,共7页
Magnesium sulfate was proposed to be leaching agent to deal with the ion-adsorption type rare earths ore to reduce or even eliminate ammonia?nitrogen emissions. The effects of temperature, particle size and stirring s... Magnesium sulfate was proposed to be leaching agent to deal with the ion-adsorption type rare earths ore to reduce or even eliminate ammonia?nitrogen emissions. The effects of temperature, particle size and stirring speed on rare earth leaching process and the leaching behaviors of the single rare earth element were investigated in order to reveal the rare earth leaching characteristics. Besides, the comparison of leaching effects between magnesium sulfate and ammonium sulfate was also studied. The results showed that the rare earth leaching process could be well described with inner diffusion control model and the apparent activation energy was 9.48 kJ/mol. The leaching behaviors of the single rare earth element were brought into correspondence with rare earths. Moreover, when the concentration of leaching agent was 0.20 mol/L, the rare earth leaching efficiency could all reach above 95% and the leaching efficiency of aluminum impurities could be restrained by 10% using magnesium sulfate compared with ammonium sulfate. 展开更多
关键词 rare earth leaching agent kinetics magnesium sulfate ion-adsorption type rare earths ore
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Column leaching process of rare earth and aluminum from weathered crust elution-deposited rare earth ore with ammonium salts 被引量:18
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作者 何正艳 张臻悦 +4 位作者 余军霞 徐志高 徐源来 周芳 池汝安 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第11期3024-3033,共10页
In order to better understand the leaching process of rare earth (RE) and aluminum (Al) from the weathered crust elutiondepositedRE ore, the mass transfer of RE and Al in column leaching was investigated using the... In order to better understand the leaching process of rare earth (RE) and aluminum (Al) from the weathered crust elutiondepositedRE ore, the mass transfer of RE and Al in column leaching was investigated using the chromatographic plate theory. Theresults show that a higher initial ammonium concentration in a certain range can enhance the mass transfer process. pH of leachingagent in the range of 2 to 8 almost has no effect on the mass transfer efficiency of RE, but plays a positive role in the mass transferefficiency of Al under strong acidic condition (pH〈4). There is an optimum flow rate that makes the highest mass transfer efficiency.The optimum leaching condition of RE is the leaching agent pH of 4?8, ammonium concentration of 0.4 mol/L and flow rate of0.5 mL/min. The mass transfer efficiencies of RE and Al both follow the order: (NH4)2SO4〈NH4Cl〈NH4NO3, implying thecomplexing ability of anion. 展开更多
关键词 column leaching process weathered crust elution-deposited rare earth ore rare earth ALUMINUM ammonium salt MASSTRANSFER
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Determination of 16 Rare Earth Elements in Banana by Microwave Digestion and ICP-MS 被引量:1
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作者 范稚莉 范稚莲 +5 位作者 闫飞燕 莫磊兴 王天顺 廖洁 牙禹 范业赓 《Agricultural Science & Technology》 CAS 2013年第11期1583-1586,共4页
[Objective] This study aimed to investigate the residues of rare earth ele-ments in Guangxi banana from banana-producing area with application of rare earth fertilizers and evaluate the safety of using rare earth fert... [Objective] This study aimed to investigate the residues of rare earth ele-ments in Guangxi banana from banana-producing area with application of rare earth fertilizers and evaluate the safety of using rare earth fertilizers in banana production. [Method] HNO3+H2O2 mixed acid system with high pressure airtight microwave di-gestion sample pretreatment method and ICP-MS technology were used, to establish a determination method of 16 rare earth elements in banana samples, including Sc45, Y89, La139, Ce140, Pr141, Sm147, Eu153, Gb157, Tb159, Nd144, Dy163, Ho165, Er166, Tm169, Yb172 and Lu175. [Result] Different standard curves present-ed good linearity. Detection limit of the instrument was 0.002-0.01 μg/L; detection limit of the method was 0.1-0.6 μg/kg; recovery rate of standard addition was 94.5%-116%; relative standard deviation was 2.02%-14.21%. [Conclusion] This method has many advantages, such as simple mass spectrogram, high sensitivity and high selectivity, accurate quantification, high precision and accuracy, simple operation, high reproducibility and high recovery rate, which is suitable for the detection of rare earth elements in banana and other fruits, with certain theoretical and applicable val-ue for guiding banana production and high-efficient planting. 展开更多
关键词 rare earth elements BANANA ICP-MS
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Effect of Seed Soaking with Rare Earth on the Seed Germination and Seedling Growth of Tartary Buckwheat under Different Water Conditions 被引量:1
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作者 石艳华 张永清 《Agricultural Science & Technology》 CAS 2013年第9期1237-1243,共7页
[Objective] This study aimed to investigate the effect of soaked seed with rare earth on the seed germination and seedling growth of tartary buckwheat under different water conditions. [Method] A hydroponic experiment... [Objective] This study aimed to investigate the effect of soaked seed with rare earth on the seed germination and seedling growth of tartary buckwheat under different water conditions. [Method] A hydroponic experiment was carried out with the seeds of tartary buckwheat variety "Heifeng No.1" in the year 2012. [Result] ①In the normal irrigation, suitable concentration of rare earth increased the germination rate, vital index, germination index and sprouting index of tartary buckwheat seed; at the same time, the leaf area, stem thickness, total root length, root weight,leaf relative water content, proline content, soluble sugar content, soluble protein content, root activity, SOD activity and POD activity of seedling were significantly enhanced, while the relative conductivity and MDA content of tartary buckwheat were decreased obviously. ② Compared with water stress and normal irrigation, the indices of germination potential, germination rate, vital index, germination index, the leaf area, stem thickness, total root length, root weight, leaf relative water content,proline content, chlorophyll content, soluble sugar content, root activity, SOD and POD activity were reduced, while relative conductivity and MDA content were increased, and the extents differed in the treatment of different chemical regulators,and the varied range increased with the higher severity of soil water stress. ③ Under water stress, soaking seeds with suitable concentration(200 mg/L) of rare earth could significantly improve the SOD and POD activity, leaf area, total root length,chlorophyll content and root activity compared with CK. They could increase leaf relative water content by 8.9% and 10.8%, proline content by 7.5% and 8.2%, TTC activity by 13.8% and 16.7%, and soluble sugar content by 10.4% and 7.9% under mild and severe water stress, separately. [Conclusion] The appropriate concentration of rare earth was 200 mg/L. 展开更多
关键词 rare earth Soaking seed Tartary buckwheat Physiological index
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Numerical simulation of fluid dynamics in rare earth chloride solution in jet-flow pyrolysis reactor
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作者 吕超 赵秋月 +3 位作者 张子木 豆志河 张廷安 赵洪亮 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期997-1003,共7页
Rare earth oxide was prepared via direct pyrolysis of rare earth chloride solution. Based on this technique, a new-type jet-flow pyrolysis reactor was designed, and then the fluid dynamics (pressure and velocity) insi... Rare earth oxide was prepared via direct pyrolysis of rare earth chloride solution. Based on this technique, a new-type jet-flow pyrolysis reactor was designed, and then the fluid dynamics (pressure and velocity) inside the reactor was numerically simulated using a computational fluid dynamics method. The self-produced pressure (p) and the fuel inlet velocity (v) satisfied a quadratic function,p=0.06v2+0.23v?4.49. To fully utilize the combustion-generated heat in pyrolysis of rare earth chloride, an appropriate external pressure p=v2+3v?4.27 should be imposed at the feed inlet. The 1.25- and 1.5-fold increase of feed inlet diameter resulted in decline of adsorption dynamic pressure, but the intake of rare earth chloride increased by more than 30% and 60%, respectively. The fluid flow in the reactor was affected by the feeding rate; the fluid flow peaked near the throat of venturi and gradually smoothed down at the jet-flow reactor’s terminal along with the sharp decline of feeding rate. 展开更多
关键词 numerical simulation rare earth chloride jet-flow pyrolysis reactor
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Effects of Substrate Complexing Light Rare Earth on Growth,Cd Absorption and Organ Distribution of Sweet Pepper(Capsicum annuum var.annuum)
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作者 王甲辰 左强 +4 位作者 邹国元 陈曦 张琳 谷佳林 宫延刚 《Agricultural Science & Technology》 CAS 2012年第11期2394-2399,共6页
[Objective] The aim was to research effects of substrate complexing light rare earth on growth, Cd absorption and organ distribution of sweet pepper to pro- vide references for development of rhizosphere regulation pr... [Objective] The aim was to research effects of substrate complexing light rare earth on growth, Cd absorption and organ distribution of sweet pepper to pro- vide references for development of rhizosphere regulation products in farmland seri- ously polluted. [Method] In the test, effects of substrate cakes (at the same size) and light rare earth (in different doses) on growth, Cd absorption and distribution of green peppers under stress from Cd were explored with a pot experiment. [Result] When 40 mg/kg of rare earth was added into a substrate cake, plant height of pep- per seedlings and the dry weight increased by 21.52% and 11.11%, compared with control group; when Cd was at 5.19 mg/kg (a highly graded pollution), the shoot biomass, olant biomass and dry weight of fruits all enhanced significantly, but root system changed little in the groups where substrate cakes were saved, compared with the group where the substrate cake was washed away. No matter RE was added into substrate cakes or not, root system was significantly inhibited by Cd stress (5.19 mg/kg), but RE at proper dose improved growth of green pepper and had little effect on fruit yielding. In addition, RE had little inhibition on Cd content in roots. RE at 10 mg/kg promoted Cd contents in stems and leaves, but reduced the content in fruits substantially. The regressive equation of Cd content and rare dose in leaves was as follows: y=4E-05x%0.009 6x+0.655 6, FF=0.542 6; the regression equations of Cd content in root, stem and fruit did not make sense. [Conclusion] The experiment lays foundation for further research on heavy metals rhizosphere complexing controlling. 展开更多
关键词 Rhizosphere regulation Substrate cake Light rare earth Cd absorption
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Rare earth ion modified TiO_2 sols for photocatalysis application under visible light excitation 被引量:39
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作者 XIEYibing YUANChunwei 《Rare Metals》 SCIE EI CAS CSCD 2004年第1期20-26,共7页
TiO_2 sols modified by rare earth (RE) ions (Ce^(4+), Eu^(3+), or Nd^(3+))were prepared by coprecipitation-peptization method. The photocatalysis activity was studied byinvestigating the photodegradation effects of ac... TiO_2 sols modified by rare earth (RE) ions (Ce^(4+), Eu^(3+), or Nd^(3+))were prepared by coprecipitation-peptization method. The photocatalysis activity was studied byinvestigating the photodegradation effects of active brilliant red dye X-3B. It is found that TiO_2sols modified by Ce^(4+), Eu^(3+), or Nd^(3+) have the anatase crystalline structure, which areprepared at 70℃. All RE^(n+)-TiO_2 sol samples have uniform nanoparticles with similar morphology,which are homogenously distributed in aqueous colloidal systems. The particle sizes are 10, 8, and12 nm for Nd^(3+)-TiO_2, Eu^(3+)-TiO_2, and Ce^(4+)-TiO_2, respectively. The character of ultrafineand positive charge sol particles contributes to the good adsorption of X-3B dye molecule on thesurface of titania (about 30% X-3B adsorption amount). Experimental results exhibit thatRE^(n+)-TiO_2 sol photocatalysts have the capability to photodegrade X-3B under visible lightirradiation. Nd^(3+)-TiO_2 and Eu^(3+)-TiO_2 show higher photocatalytic activity than Ce^(4+)-TiO_2,which is due to the difference of standard redox potential of RE^(n+)/RE^((n-1)+). RE^(n+)-TiO_2sols demonstrate more excellent interfacial adsorption and photodegradation effects to X-3B thanP_(25) TiO_2 crystallites. Moreover, the degradation mechanism of X-3B is proposed as dyephotosensitization and electron scavenging by rare earth ions. 展开更多
关键词 PHOTOCATALYSIS TiO_2 rare earth ion PHOTOSENSITIZATion
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Biomedical rare-earth magnesium alloy:Current status and future prospects 被引量:1
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作者 Mingli Yang Cheng Chen +5 位作者 Dongsheng Wang Yinjin Shao Wenhao Zhou Cijun Shuai Youwen Yang Xinghai Ning 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1260-1282,共23页
Biomedical magnesium(Mg)alloys have garnered significant attention because of their unique biodegradability,favorable biocompatibility,and suitable mechanical properties.The incorporation of rare earth(RE)elements,wit... Biomedical magnesium(Mg)alloys have garnered significant attention because of their unique biodegradability,favorable biocompatibility,and suitable mechanical properties.The incorporation of rare earth(RE)elements,with their distinct physical and chemical properties,has greatly contributed to enhancing the mechanical performance,degradation behavior,and biological performance of biomedical Mg alloys.Currently,a series of RE-Mg alloys are being designed and investigated for orthopedic implants and cardiovascular stents,achieving substantial and encouraging research progress.In this work,a comprehensive summary of the state-of-the-art in biomedical RE-Mg alloys is provided.The physiological effects and design standards of RE elements in biomedical Mg alloys are discussed.Particularly,the degradation behavior and mechanical properties,including their underlying action are studied in-depth.Furthermore,the preparation techniques and current application status of RE-Mg alloys are reviewed.Finally,we address the ongoing challenges and propose future prospects to guide the development of high-performance biomedical Mg-RE alloys. 展开更多
关键词 Magnesium alloy rare earth elements Biodegradation behavior Mechanical performance Biological properties
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