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Exploiting fly models to investigate rare human neurological disorders
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作者 Tomomi Tanaka Hyung-Lok Chung 《Neural Regeneration Research》 SCIE CAS 2025年第1期21-28,共8页
Rare neurological diseases,while individually are rare,collectively impact millions globally,leading to diverse and often severe neurological symptoms.Often attributed to genetic mutations that disrupt protein functio... Rare neurological diseases,while individually are rare,collectively impact millions globally,leading to diverse and often severe neurological symptoms.Often attributed to genetic mutations that disrupt protein function or structure,understanding their genetic basis is crucial for accurate diagnosis and targeted therapies.To investigate the underlying pathogenesis of these conditions,researchers often use non-mammalian model organisms,such as Drosophila(fruit flies),which is valued for their genetic manipulability,cost-efficiency,and preservation of genes and biological functions across evolutionary time.Genetic tools available in Drosophila,including CRISPR-Cas9,offer a means to manipulate gene expression,allowing for a deep exploration of the genetic underpinnings of rare neurological diseases.Drosophila boasts a versatile genetic toolkit,rapid generation turnover,and ease of large-scale experimentation,making it an invaluable resource for identifying potential drug candidates.Researchers can expose flies carrying disease-associated mutations to various compounds,rapidly pinpointing promising therapeutic agents for further investigation in mammalian models and,ultimately,clinical trials.In this comprehensive review,we explore rare neurological diseases where fly research has significantly contributed to our understanding of their genetic basis,pathophysiology,and potential therapeutic implications.We discuss rare diseases associated with both neuron-expressed and glial-expressed genes.Specific cases include mutations in CDK19 resulting in epilepsy and developmental delay,mutations in TIAM1 leading to a neurodevelopmental disorder with seizures and language delay,and mutations in IRF2BPL causing seizures,a neurodevelopmental disorder with regression,loss of speech,and abnormal movements.And we explore mutations in EMC1 related to cerebellar atrophy,visual impairment,psychomotor retardation,and gain-of-function mutations in ACOX1 causing Mitchell syndrome.Loss-of-function mutations in ACOX1 result in ACOX1 deficiency,characterized by very-long-chain fatty acid accumulation and glial degeneration.Notably,this review highlights how modeling these diseases in Drosophila has provided valuable insights into their pathophysiology,offering a platform for the rapid identification of potential therapeutic interventions.Rare neurological diseases involve a wide range of expression systems,and sometimes common phenotypes can be found among different genes that cause abnormalities in neurons or glia.Furthermore,mutations within the same gene may result in varying functional outcomes,such as complete loss of function,partial loss of function,or gain-of-function mutations.The phenotypes observed in patients can differ significantly,underscoring the complexity of these conditions.In conclusion,Drosophila represents an indispensable and cost-effective tool for investigating rare neurological diseases.By facilitating the modeling of these conditions,Drosophila contributes to a deeper understanding of their genetic basis,pathophysiology,and potential therapies.This approach accelerates the discovery of promising drug candidates,ultimately benefiting patients affected by these complex and understudied diseases. 展开更多
关键词 ACOX1 Drosophila melanogaster GLIA lipid metabolism model organisms NEUROINFLAMMATION neurologic disorders NEURON rare disease VLCFA
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Study on Copolymerization of Rare Earth-Carboxylic Acid Complex 被引量:1
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作者 邱关明 张明 +3 位作者 严长浩 周兰香 戴少俊 Okamo to Hiroshi 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第6期618-621,共4页
Complex of rare earth with carboxylic acid was prepared by precipitation and direct method. It was copolymerized with such monomers as acrylic acid and other ones to synthesize ionomer of rare earth and organic polyme... Complex of rare earth with carboxylic acid was prepared by precipitation and direct method. It was copolymerized with such monomers as acrylic acid and other ones to synthesize ionomer of rare earth and organic polymer with different rare earth contents. Its glass-transition temperature and heat stability were analyzed by TG and DTA. Infra-red detector was used to show its structure. The effect of rare earth complex prepared by different methods on copolymerization and properties of copolymers was also discussed. 展开更多
关键词 organic material rare earth ionomer COPOLYMERIZATION rare earth complex monomer rare earth-carboxylic acid complex rare earths
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Study on Rare Earth-Containing Phases in TiAl Based Alloys Prepared by Non-Equilibrium Solidification Processing 被引量:1
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作者 马学著 沈军 贾均 《Journal of Rare Earths》 SCIE EI CAS CSCD 2001年第2期103-106,共4页
Microstructure evolution of rare earth rich phase of rapidly-solidified (RS) TiAl based alloys was investigated. The two rapid-solidification techniques employed are melt-spinning technique (MS) and Hammer-and-Anvil t... Microstructure evolution of rare earth rich phase of rapidly-solidified (RS) TiAl based alloys was investigated. The two rapid-solidification techniques employed are melt-spinning technique (MS) and Hammer-and-Anvil technique (HB). MS ribbons and HA foils were obtained in the experiment. The results demonstrate that with the increasing of cooling rates of TiAl based alloys great changes are taken place in the microstructures of rare earth rich phase, from scattering mainly on grain boundaries of as-cast ingot to distributing homogeneously as very fine fibers or powders (nanometer grade) on the matrix. The fine paralleling second phase fibers in the HA foils are considered to be connected with gamma/alpha (2) lamellar colonies. Selected area electronic diffraction (SAED) patterns of the rare earth rich phase is in accordance with that of intermetallic AlCe. 展开更多
关键词 rare earths rapid solidification rare earth rich phase TiAl based alloy microstructure
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Phenomena of Periodic Precipitaion in Rare Earth-Cholate Diffusion Systems 被引量:1
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作者 Xie Datao, Wang Libo, Wu Jinguang, Xu Guangxian (State Key Laboratory of Rare Earth Materials Chemistry and Applications, Peking University, Beijing 100871, China) 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第2期2-4,共3页
The precipitate patterns were studied in rare earthcholate diffusion systems. The corresponding precipitates were characterized by Forie Transformed Infrared(FTIR) and Extended XRay Absorption Fine Structure(EXAFS) sp... The precipitate patterns were studied in rare earthcholate diffusion systems. The corresponding precipitates were characterized by Forie Transformed Infrared(FTIR) and Extended XRay Absorption Fine Structure(EXAFS) spectroscopy. The experimental results indicate that rare earth ions tend to produce periodic precipitation, and the pattern precipitates are just the corresponding rare earth cholate complexes. 展开更多
关键词 rare earths Periodic precipitation CHOLATE
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Enrichment characteristics and sources of the critical metal yttrium in Zhijin rare earth-containing phosphorites, Guizhou Province, China 被引量:4
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作者 Xingxiang Gong Shengwei Wu +8 位作者 Yong Xia Zhengwei Zhang Shan He Zhuojun Xie Jiafei Xiao Haiying Yang Qingping Tan Yi Huang Yuhong Yang 《Acta Geochimica》 EI CAS CSCD 2021年第3期441-465,共25页
Yttrium(Y)is a critical metallic element that is used widely in modern scientific,technological,and industrial applications.Phosphorites in the Zhijin area of Guizhou Province,China,are famous for Y enrichment,but the... Yttrium(Y)is a critical metallic element that is used widely in modern scientific,technological,and industrial applications.Phosphorites in the Zhijin area of Guizhou Province,China,are famous for Y enrichment,but the enrichment characteristics and sources remain unclear.Previous studies suggested that the sources of rare earth elements(REEs,La-Lu)and Y(REYs,La-Lu+Y)were related to hydrothermal deposition.However,this study presents evidence refuting that hypothesis,with major and trace elemental data collected with quadrupoleinductively coupled plasma-mass spectrometry(Q-ICPMS)analysis.These data show that Y in Zhijin REYscontaining phosphorites has a normal distribution and is particularly enriched relative to other REYs.The Y enrichment degree is different at different∑REY intervals.Specifically,the Y enrichment degree is higher at lower∑REY values and lower at higher∑REY values.The REYs-containing phosphorites show features of primary phosphorites.Both REEs and Y have good correlations with P2 O5 in the phosphorites with low REYs contents(total REYs<535 ppm),whereas at high REYs contents(total REYs>535 ppm),REEs have a good correlation with P2 O5 but Y does not.Inconsistent enrichment processes of REYs are suggestive of complex sources of Y.Thus,seafloor hydrothermal fluids were not the direct source of Y.Normal seawater mixed with terrestrial sources might have contributed to the origin of Y here.This study could lead to improvements in Y mineral resource explorations and the situation involving the global REYs supply crisis. 展开更多
关键词 YTTRIUM PHOSPHORITES rare earth elements Trace elements Enrichment processes
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Synthesis, Characterization of α-Oxopentanedioic Acid-Isonicotinoyl (Hydrazone) Rare Earth-Complexes and Relaxivity of Gd-complex
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作者 杨正银 杨汝栋 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第3期327-330,共4页
Oxopentanedioic acid isonicotinoyl hydrazone (H_2L) and its five rare earth complexes were synthesized with a view to further investigating MRI activities of the polycarboxylic Schiff base complexes. The complexes wer... Oxopentanedioic acid isonicotinoyl hydrazone (H_2L) and its five rare earth complexes were synthesized with a view to further investigating MRI activities of the polycarboxylic Schiff base complexes. The complexes were characterized on the basis of elemental analyses, IR, UV, (()~1H) NMR spectra and thermal analyses. The general formula of the complexes is [Ln(HL)(H_2O)_2]Cl_2·H_2O (where Ln(Ⅲ)=La, Pr, Nd, Eu and Gd). In addition, the relaxivity ( R _1) of the Gd-complex was determined by INVREC Au program. 展开更多
关键词 inorgonic chemistry MRI contrast agent RELAXIVITY rare earth complexes
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Thermal Oxidation Resistance of Rare Earth-Containing Composite Elastomer
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作者 邱关明 张明 +3 位作者 周兰香 中北里志 井上真一 冈本弘 《Journal of Rare Earths》 SCIE EI CAS CSCD 2001年第3期192-197,共6页
The rare earth-containing composite elastomer was obtained by the reaction of vinyl pyridine-SBR (PSBR) latex with rare earth alkoxides, and its thermal oxidation resistance was studied. After aging test, it is found ... The rare earth-containing composite elastomer was obtained by the reaction of vinyl pyridine-SBR (PSBR) latex with rare earth alkoxides, and its thermal oxidation resistance was studied. After aging test, it is found that its retention rate of mechanical properties is far higher than that of the control sample. The results of thermogravimetric analysis show that its thermal-decomposing temperature rises largely. The analysis of oxidation mechanisms indicates that the main reasons for thermal oxidation resistance are that rare earth elements are of the utility to discontinue autoxidation chain reaction and that the formed complex structure has steric hindrance effect on oxidation. 展开更多
关键词 rare earths composite elastomer thermal oxidation resistance discontinue autoxidation steric structure
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Formability of Rare Earth-Containing Solid Solution Based on Compounds with Scheelite-Type Structure
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作者 Luo Yunyun Bao Xinhua +2 位作者 Lu Wencong Chen Nianyi Xia Yiben 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第4期I0010-I0010,共1页
The regularities of the solid solutions between the scheelite-type compounds and rare earth molybdates or tungstates were investigated by the atomic parameter-support vector machine method and the intelligent database... The regularities of the solid solutions between the scheelite-type compounds and rare earth molybdates or tungstates were investigated by the atomic parameter-support vector machine method and the intelligent database of phase diagrams of molten salt systems. The crystal structure of scheelite-type compounds having M^1M^′Ⅲ (XO4)2(X = Mo, W) as common formula and the formability of the continuous solid solution between these compounds and rare earth molybdates or tungstates were also investigated. Besides, the cell constants of these compounds can be calculated by some semi-empirical equations. Based on the obtained relationships, the results of computerized prediction of the solid solubility of T1Pr (MoO4)2-Pr2 (MoO4)3 system have good agreement with experimental results. 展开更多
关键词 scheelite-type structure solid solution support vector machine (SVM) intelligent data base of phase diagrams rare earth materials design
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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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Response and assembly of abundant and rare taxa in Zaopei under different combination patterns of Daqu and pit mud:from microbial ecology to Baijiu brewing microecosystem 被引量:1
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作者 Yu Mu Jun Huang +5 位作者 Rongqing Zhou Suyi Zhang Hui Qin Hanlan Tang Qianglin Pan Huifang Tang 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1439-1452,共14页
The quality and aroma of strong-flavor Baijiu are mainly dependent on Daqu,pit mud(PM),and the interaction of both.However,little is known about how their combination patterns affect the microbiome and metabolome of Z... The quality and aroma of strong-flavor Baijiu are mainly dependent on Daqu,pit mud(PM),and the interaction of both.However,little is known about how their combination patterns affect the microbiome and metabolome of Zaopei,especially the metabolic function of rare taxa.Here,an experiment on industrial size was designed to assess the effects of 6 combinations(3 kinds of Daqu×2 kinds of PM)on the composition and assembly of different taxa,as well as the flavor profile.The results showed that Zaopei's microbiota was composed of a few abundant taxa and enormous rare taxa,and rare bacterial and abundant fungal subcommunities were significantly affected by combination patterns.The assembly processes of abundant/rare taxa and bacterial/fungal communities were distinct,and environmental changes mediated the balance between stochastic and deterministic processes in rare bacteria assembly.Furthermore,specific combination patterns improved the flavor quality of Zaopei by enhancing the interspecies interaction,which was closely related to rare taxa,especially rare bacteria.These findings highlighted that rare bacteria might be the keystone in involving community interaction and maintaining metabolic function,which provided a scientific foundation for better understanding and regulating the brewing microbiota from the viewpoint of microbial ecology. 展开更多
关键词 Bioaugmented Daqu Artificial pit mud Abundant and rare taxa Community assembly Metabolic function
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Effect of Rare-Earth Element Substitution in Superconducting R_(3)Ni_(2)O_(7) under Pressure
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作者 Zhiming Pan Chen Lu +1 位作者 Fan Yang Congjun Wu 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第8期77-81,共5页
Recently,high temperature(T_(c)≈80 K)superconductivity(SC)has been discovered in La_(3)Ni_(2)O_(7)(LNO)under pressure.This raises the question of whether the superconducting transition temperature T_(c) could be furt... Recently,high temperature(T_(c)≈80 K)superconductivity(SC)has been discovered in La_(3)Ni_(2)O_(7)(LNO)under pressure.This raises the question of whether the superconducting transition temperature T_(c) could be further enhanced under suitable conditions.One possible route for achieving higher T_(c) is element substitution.Similar SC could appear in the Fmmm phase of rare-earth(RE)R_(3)Ni_(2)O_(7)(RNO,R=RE element)material series under suitable pressure.The electronic properties in the RNO materials are dominated by the Ni 3d orbitals in the bilayer NiO_(2) plane.In the strong coupling limit,the SC could be fully characterized by a bilayer single 3d_(x^(2)−y^(2))-orbital t–J‖–J⊥ model.With RE element substitution from La to other RE element,the lattice constant of the Fmmm RNO material decreases,and the resultant electronic hopping integral increases,leading to stronger superexchanges between the 3d_(x^(2)−y^(2)) orbitals.Based on the slave-boson mean-field theory,we explore the pairing nature and the evolution of T_(c) in RNO materials under pressure.Consequently,it is found that the element substitution does not alter the pairing nature,i.e.,the inter-layer s-wave pairing is always favored in the superconducting RNO under pressure.However,the T_(c) increases from La to Sm,and a nearly doubled T_(c) could be realized in SmNO under pressure.This work provides evidence for possible higher T_(c) R_(3)Ni_(2)O_(7) materials,which may be realized in further experiments. 展开更多
关键词 ELEMENT SUBSTITUTION rare
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Primary unifocal penile follicular center non-Hodgkin lymphoma:Report of a rare case and review of the literature
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作者 Nikolaos Kostakopoulos Christos Masaoutis +4 位作者 Vasileios Argyropoulos Varvara Pantelaion Panagiotis Theodoropoulos Panagiotis Kouroupakis Athanasios Kostakopoulos 《Asian Journal of Urology》 CSCD 2024年第1期134-136,共3页
Dear Editor,We present a rare case of a primary penile follicular center non-Hodgkin lymphoma and a review of the available literature on this condition.A BCL2 gene transposition which was identified with fluorescent ... Dear Editor,We present a rare case of a primary penile follicular center non-Hodgkin lymphoma and a review of the available literature on this condition.A BCL2 gene transposition which was identified with fluorescent in situ hybridization(FISH)molecular analysis is a unique manifestation not previously reported to the best of our knowledge.A 67-year-old man presented with a 3-month history of a small nodule on the left side of the corona of glans penis.The patient had no significant medical or family history.The patient underwent excision and biopsy of the penile lesion with a 0.5 cm macroscopic margin under local anesthesia and sedation.He was discharged on the day of surgery,and there were no postoperative complications or adverse events.The informed consent was obtained from thepatient. 展开更多
关键词 ANESTHESIA LYMPHOMA rare
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A rare case of cardiac and ophthalmic manifestations of meningococcal septicemia
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作者 Svetlana Rachina Anastasia Shchendrygina +13 位作者 Heshan Radeesha de Silva Svetlana Tarasenko Nadezhda Mukhina Irina Komarova Ludmila Fedina Elena Burmistrova Elvira Martens Sergey Sidorenko Vladimir Gostev Dmitry Polev Alina Saitova Lyudmila Kraeva Nikita Goncharov Irina Zvetkova 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第4期328-330,共3页
Acute pericarditis is usually a self-limiting disorder that commonly occurs due to viral etiology or unexplained causes.Meningococcal pericarditis(MP)is a remarkably uncommon clinical entity that manifests as a compli... Acute pericarditis is usually a self-limiting disorder that commonly occurs due to viral etiology or unexplained causes.Meningococcal pericarditis(MP)is a remarkably uncommon clinical entity that manifests as a complication during the acute or convalescent phase of meningococcal meningitis.However,its occurrence within the context of meningococcal septicemia has also been documented.We report a rare case of a previously healthy male patient who developed both acute pericarditis and uveitis as a presentation of meningococcal septicemia,with no characteristic skin rashes or meningeal signs. 展开更多
关键词 ACUTE ACUTE rare
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Soil properties and not plant factors affect both abundant and rare microbial taxa after thinning in a mixed stand of Cunninghamia lanceolata and Sassafras tzumu
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作者 Wanxia Peng Tongqing Song +5 位作者 Hu Du Feng Wang Fuping Zeng Yang Wang Shulin Chen Yinzhu Chen 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期81-94,共14页
Thinning is an effective management step for sustainable forest development,yet less attention is paid to the restoration of soil microbiota after thinning.In this study,both abundant and rare soil microbial communiti... Thinning is an effective management step for sustainable forest development,yet less attention is paid to the restoration of soil microbiota after thinning.In this study,both abundant and rare soil microbial communities(i.e.,bacterial,fungal),were evaluated under various thinning treatments in a mixed stand of Cunninghamia lanceolata and Sassafras tzumu using Mi Seq sequencing.Thinning did not significantly change either abundant or rare bacterial and fungal community composition,but affected their alpha diversity.The Shannon–Wiener indexes of rare fungal taxa under medium thinning were significantly lower than in the light thinning(P<0.05 level).Xanthobacteraceae dominated the abundant bacterial taxa,and Saitozyma and Mortierlla the abundant fungal taxa.The most common rare bacterial taxa varied;there was no prevalent rare fungal taxa under different thinnings.In addition,soil available nitrogen,total phosphorus,and p H had significant effects on rare bacterial taxa.Nutrients,especially available phosphorus,but not nitrogen,affected abundant and rare soil fungi.The results indicate that soil properties rather than plant factors affect abundant and rare microbial communities in soils of mixed stands.Thinning,through mediating soil properties,influences both abundant and rare bacterial and fungal communities in the mixed C.lanceolata and S.tzumu stand. 展开更多
关键词 Diversity Abundant taxa rare taxa THINNING Mixed stand
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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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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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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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Changes in Sediment Sources in the Southern Muddy Area of Weihai,China,Since the Late Pleistocene:A Record from Rare Earth Elements
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作者 ZHANG Zhichao LIU Jinqing +3 位作者 YIN Ping CAO Ke FENG Xiaokun WANG Shengyu 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第5期1221-1232,共12页
The small muddy areas developed in the southern Shandong Peninsula have attracted increasing attention from researchers because of complex changes in sediment sources driven by sea-level fluctuations and land-sea inte... The small muddy areas developed in the southern Shandong Peninsula have attracted increasing attention from researchers because of complex changes in sediment sources driven by sea-level fluctuations and land-sea interactions since the late Pleistocene.This study investigates the evolution of sediment sources and their responses to environmental changes since the late Pleistocene,using core WHZK01 collected from the nearshore muddy area in southern Weihai for rare earth element(REE)analysis.In doing so,this work highlights the changing patterns of material sources and the primary control factors.The results reveal that the sedimentary deposits in core WHZK01 exhibit distinct terrestrial characteristics.Discriminant function analysis(F_(D))and source discrimination dia-grams both suggest that the primary sources of these deposits are the Yellow River and adjacent small and medium-sized rivers,although the sources vary among different sedimentary units.Furthermore,the DU3 layer(17.82-25.10 m)displays typical riverine sedimentation,dominated by terrestrial detrital input,primarily from the local rivers,namely the Huanglei and Muzhu Rivers.The material in the DU2 layer(14.91-17.82 m)is mainly influenced by a mixture of the Qinglong and Yellow Rivers.The DU1 layer(0-14.91 m)is influenced by sea-level changes during the Holocene,with the Yellow River being the primary source,although there is also some input from local rivers.The changes in sea level during the Holocene and the input of Yellow River material carried by the coastal currents of the Yellow Sea are identified as the main controlling factors for the changes in material sources in the study area since the late Pleistocene,with small and mediumsized rivers also exerting some influence on the material sources.The above mentioned findings not only contribute to a better understanding of the source-sink systems of the Yellow River and adjacent small and mediumsized rivers but also deepen our understanding of the late Quaternary land-sea interactions in the Shandong Peninsula. 展开更多
关键词 rare earth element source identification environmental evolution muddy area southern Weihai
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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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Orientations of Rare-earth-containing Heteropolyoxometalates with Different Sizes in the Interlayer of Synthetic Multibilayer Films
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作者 Yong Hui WANG Xin Long WANG +1 位作者 Chang Wen HU En Bo WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第9期887-890,共4页
Three rare-earth-containing heteropolyoxometalates with different sizes, Na9[Eu(W5 O18)2], K13[Eu(SiW11O39)2], and K17[Eu(P2W17O61)2], have been incorporated by self-assembly into the interlayer of synthetic multibila... Three rare-earth-containing heteropolyoxometalates with different sizes, Na9[Eu(W5 O18)2], K13[Eu(SiW11O39)2], and K17[Eu(P2W17O61)2], have been incorporated by self-assembly into the interlayer of synthetic multibilayer films of dimethyldioctadecylammonium chloride and exhibited different orientations. 展开更多
关键词 rare-earth-containing heteropolyoxometalate synthetic multibilayer film DODA orientation.
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