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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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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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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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Biomedical rare-earth magnesium alloy:Current status and future prospects
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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
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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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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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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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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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Rare-Element Pegmatites Rocks Rich and Li of the Aïr Massif of the Tchirozerine: Mineralogy and Chemical Composition Agadez Region-Northem Niger
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作者 Ntoumbé Mama Hamza Bassara +2 位作者 Amaya Adama Awona Paul Zéphyrin Nomenjanahary Limbisoa 《Open Journal of Applied Sciences》 2024年第1期171-181,共11页
The lithium potential in the Aïr massif is represented by mineral index of spodumene pegmatites and, lepidolite pegmatites. The mineral deposits of lithium occur in cluster or veins that cut the host rock or are ... The lithium potential in the Aïr massif is represented by mineral index of spodumene pegmatites and, lepidolite pegmatites. The mineral deposits of lithium occur in cluster or veins that cut the host rock or are located near the contact between the greenstone belt and granitic massif. The evidence of lithium is in the form of clusters or disseminated and stockwerk. Mineralogical characteristics show similarities between the Air Massif pegmatites and indicate the same homogenous source during the magma-generation process. The pegmatite rocks attracted the attention due to their wide exposure and composition, well appearance, and economically hosting of significant rare earth metals such as Sn and W. The mineralogical and petrographical investigations on the eight pegmatites rocks samples observed have a relative similarity, while a little difference in the shapes attributed to the ratio in the pegmatite rocks of the minerals. The occurrence of the kink band indicates the influence of the tectonic processes which affected the Aïr massif after the emplacement of late magmatic or post-magmatic pegmatites by injection into fractured rocks in the upper part of the crust. The Air Massif pegmatite has higher concentrations Li and of all trace elements except Hf and occasionally Zr, Ti, Sn and Mg of for the economic exploration. 展开更多
关键词 PEGMATITE Lithium rare Elements Hydrothermal Processes Aïr Massif
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Primary pulmonary meningioma and minute pulmonary meningothelial-like nodules: Rare pulmonary nodular lesions requiring more awareness in clinical practice
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作者 Li-Dan Liu Ke-Xin Zhang +2 位作者 Hai-Ning Zhang Yi-Wen Zheng Hong-Tao Xu 《World Journal of Clinical Cases》 SCIE 2024年第11期1857-1862,共6页
In this editorial,we comment on an article by Ruan et al published in a recent issue of the World Journal of Clinical Case.Pulmonary meningothelial proliferative lesions,including primary pulmonary meningiomas,minute ... In this editorial,we comment on an article by Ruan et al published in a recent issue of the World Journal of Clinical Case.Pulmonary meningothelial proliferative lesions,including primary pulmonary meningiomas,minute pulmonary meningothelial-like nodules,and metastatic pulmonary meningiomas are rare pulmonary lesions.These lesions are difficult to differentiate from lung cancers based on clinical and imaging manifestations.Herein,we briefly introduce the clinical,imaging,and pathological characteristics of these lesions and discuss their pathogenesis to strengthen the current understanding of pulmonary meningothelial proliferative lesions in clinical diagnosis and therapy. 展开更多
关键词 Pulmonary meningothelial proliferation Primary pulmonary meningioma Minute pulmonary meningothelial-like nodule Lung neoplasm rare pulmonary nodular lesion
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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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Development and characteristics of a low rare-earth containing magnesium alloy with high strength-ductility synergy 被引量:2
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作者 Zijian Yu Xi Xu +6 位作者 Kang Shi Baotian Du Xiuzhu Han Tao Xiao Shubo Li Ke Liu Wenbo Du 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第5期1629-1642,共14页
In this study,we successfully developed a low RE containing Mg-3Y-2Gd-1Nd-0.5Zr(wt%)alloy with high strength-ductility synergy by combined processes of hot extrusion,hot rolling and ageing.This alloy exhibits an excel... In this study,we successfully developed a low RE containing Mg-3Y-2Gd-1Nd-0.5Zr(wt%)alloy with high strength-ductility synergy by combined processes of hot extrusion,hot rolling and ageing.This alloy exhibits an excellent strength-ductility balance(UTS of 345±2.0 MPa,TYS of 301±5.0 MPa and EL of 9.2±1.9%),which is better than that of many Mg-RE wrought alloys with higher RE concentration and even comparable to that of 6061 Al wrought alloy.A long-range chain-like structure consisting ofβphase,βH phase,βM phase and zig-zag atomic columns is observed for the first time in the studied alloy.The combined process of hot extrusion and hot rolling boosts the formation of deformed grains and low angle grain boundaries,and makes the deformed grains dominate in the alloy strengthening.Under this circumstance,the following ageing generates a novel heterogeneous structure comprising the long-range chain-like structure with broad interparticle spacing and the spacious precipitate-free zones in the deformed grains,which plays a key role in the concurrent strengthening and toughening of the alloy.The present study demonstrates that the deformed grains with long-range chain-like structures and precipitate-free zones is desirable microstructure for the low RE containing Mg alloys to achieve high strength-ductility synergy. 展开更多
关键词 Magnesium alloy Microstructure Mechanical properties rare earth
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Influence of rare earth Ce on hot deformation behavior of as-cast Mn18Cr18N high nitrogen austenitic stainless steel 被引量:4
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作者 Yushuo Li Yanwu Dong +3 位作者 Zhouhua Jiang Qingfei Tang Shuyang Du Zhiwen Hou 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第2期324-334,共11页
The hot deformation behavior of Mn18Cr18N and Mn18Cr18N+Ce high nitrogen austenitic stainless steels at 1173-1473 K and 0.01-1 s^(-1) were investigated by thermal compression tests.The influence mechanism of Ce on the... The hot deformation behavior of Mn18Cr18N and Mn18Cr18N+Ce high nitrogen austenitic stainless steels at 1173-1473 K and 0.01-1 s^(-1) were investigated by thermal compression tests.The influence mechanism of Ce on the hot deformation behavior was analyzed by Ce-containing inclusions and segregation of Ce.The results show that after the addition of Ce,large,angular,hard,and brittle inclusions(TiN-Al_(2)O_(3),TiN,and Al_(2)O_(3)) can be modified to fine and dispersed Ce-containing inclusions(Ce-Al-O-S and TiN-Ce-Al-O-S).During the solidification,Ce-containing inclusions can be used as heterogeneous nucleation particles to refine as-cast grains.During the hot deformation,Ce-containing inclusions can pin dislocation movement and grain boundary migration,induce dynamic recrystallization(DRX)nucleation,and avoid the formation and propagation of micro cracks and gaps.In addition,during the solidification,Ce atoms enrich at the front of solid-li-quid interface,resulting in composition supercooling and refining the secondary dendrites.Similarly,during the hot deformation,Ce atoms tend to segregate at the boundaries of DRX grains,inhibiting the growth of grains.Under the synergistic effect of Ce-containing inclusions and Ce segregation,although the hot deformation resistance and hot deformation activation energy are improved,DRX is more likely to occur and the size of DRX grains is significantly refined,and the problem of hot deformation cracking can be alleviated.Finally,the microhardness of the samples was measured.The results show that compared with as-cast samples,the microhardness of hot-deformed samples increases signific-antly,and with the increase of DRX degree,the microhardness decreases continuously.In addition,Ce can affect the microhardness of Mn18Cr18N steel by affecting as-cast and hot deformation microstructures. 展开更多
关键词 rare earth hot deformation Mn18Cr18N steel non-metallic inclusions element segregation MICROHARDNESS
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Effect of rare earth on morphology and dispersion of TiB2 phase in Al-Ti-B alloy refiner 被引量:1
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作者 Zhi-qiang Chen Wen-xin Hu +1 位作者 Lei Shi Wei Wang 《China Foundry》 SCIE CAS CSCD 2023年第2期115-124,共10页
To investigate the effect of rare earth on size and distribution of TiB2 phase in aluminum alloy refiner,Al-5Ti-1B-RE master alloy was fabricated,and its microstructure and phase constitutions were investigated by the... To investigate the effect of rare earth on size and distribution of TiB2 phase in aluminum alloy refiner,Al-5Ti-1B-RE master alloy was fabricated,and its microstructure and phase constitutions were investigated by the combination of first principles calculations and experimental investigation.The calculated results reveal that Ce has the most effective modification ability due to the most positive adsorption energy and the largest charge transfer value compared with other rare earth elements.Results of experimental investigation indicate that the addition of rare earth in the Al-5Ti-1B alloys can greatly refine the particle size of TiB2,improve the distribution of particles and lead to better refinement effect than that of the Al-5Ti-1B alloys without rare earth.Moreover,Ce has the best optimization effect,which agrees well with the calculated results. 展开更多
关键词 Al-Ti-B refiner rare earth TIB2 distribution
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Dynamic portfolio choice with uncertain rare‑events risk in stock and cryptocurrency markets 被引量:1
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作者 Wujun Lv Tao Pang +1 位作者 Xiaobao Xia Jingzhou Yan 《Financial Innovation》 2023年第1期1967-1994,共28页
In response to the unprecedented uncertain rare events of the last decade,we derive an optimal portfolio choice problem in a semi-closed form by integrating price diffusion ambiguity,volatility diffusion ambiguity,and... In response to the unprecedented uncertain rare events of the last decade,we derive an optimal portfolio choice problem in a semi-closed form by integrating price diffusion ambiguity,volatility diffusion ambiguity,and jump ambiguity occurring in the traditional stock market and the cryptocurrency market into a single framework.We reach the following conclusions in both markets:first,price diffusion and jump ambiguity mainly determine detection-error probability;second,optimal choice is more significantly affected by price diffusion ambiguity than by jump ambiguity,and trivially affected by volatility diffusion ambiguity.In addition,investors tend to be more aggressive in a stable market than in a volatile one.Next,given a larger volatility jump size,investors tend to increase their portfolio during downward price jumps and decrease it during upward price jumps.Finally,the welfare loss caused by price diffusion ambiguity is more pronounced than that caused by jump ambiguity in an incomplete market.These findings enrich the extant literature on effects of ambiguity on the traditional stock market and the evolving cryptocurrency market.The results have implications for both investors and regulators. 展开更多
关键词 Robust portfolio choice Detection error probability rare events AMBIGUITY Cryptocurrency Welfare loss
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东昆仑大格勒地区稀有和稀土矿化碱性杂岩体的发现及意义 被引量:10
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作者 李五福 王涛 +16 位作者 王秉璋 张新远 谭运鸿 袁博武 王春涛 韩晓龙 金婷婷 郑英 曹锦山 王泰山 张焜 付长垒 陈健 刘建栋 李青 张启龙 陈丽娟 《大地构造与成矿学》 EI CAS CSCD 北大核心 2024年第1期38-49,共12页
稀有、稀土元素由于其特殊的属性对国民经济、国家安全和科技发展具有重要的战略意义。与碱性岩类相关的稀有、稀土矿产资源储量十分丰富,近年来对其勘探和开发越来越受到重视。青海省地质调查院在东昆仑中段大格勒地区首次发现了稀有... 稀有、稀土元素由于其特殊的属性对国民经济、国家安全和科技发展具有重要的战略意义。与碱性岩类相关的稀有、稀土矿产资源储量十分丰富,近年来对其勘探和开发越来越受到重视。青海省地质调查院在东昆仑中段大格勒地区首次发现了稀有和稀土矿化碱性杂岩体,岩石类型主要为含尖晶石磷灰石蛇纹石化橄榄岩、含磷灰石金云母霞石单斜辉石岩、橄榄辉长岩、含磷灰石金云母角闪石岩、磁铁矿化含橄榄石磷灰石碳酸岩等,其中含矿岩石为碳酸岩、橄榄岩、辉石岩等。矿石矿物主要为烧绿石、铌钽铁矿、磷灰石、独居石、钛铁矿。现初步圈定Nb、P矿体一条,矿体厚3.8~56.56 m,Nb_(2)O_(5)品位最高6.9%,平均0.71%;P_(2)O_(5)品位最高14.5%,平均品位5.6%,Ta和REE也伴有矿化,显示了很好的含矿性。这一发现大大拓展了青藏高原稀有、稀土矿的找矿空间,为发现新的、优质的稀有稀土矿产提供重要启示,具有重要的找矿和战略意义。 展开更多
关键词 碱性杂岩体 稀有金属 稀土矿 大格勒 东昆仑
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Unilateral laterothoracic exanthem masquerading as herpes zoster in a COVID-19 positive adult male:A rare presentation
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作者 Aurelia Goyal Sharang Gupta Dimple Chopra 《Journal of Acute Disease》 2023年第1期43-44,共2页
Dear editor,Unilateral laterothoracic exanthem(ULE),also called superimposed lateralized exanthema or asymmetric periflexural exanthem of childhood,is mostly seen in children aged between 1-5 years[1].It is often prec... Dear editor,Unilateral laterothoracic exanthem(ULE),also called superimposed lateralized exanthema or asymmetric periflexural exanthem of childhood,is mostly seen in children aged between 1-5 years[1].It is often preceded by a respiratory or gastrointestinal symptom.The eruption is usually unilateral,spreading centrifugally,which may present as maculopapular,eczematous or scarlatiniform lesions[2,3].The proposed etiologies include viral infections such as adenovirus,parvovirus,Epstein-Barr virus and most recently,the SARS-CoV-19 virus[4,5].This entity is quite rare in adults.Herein we present a case of ULE in a COVID-19 positive adult male.The condition is mostly self-limiting and requires symptomatic management. 展开更多
关键词 THORACIC ZOSTER rare
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Effects of Rare-earth and Microalloying Elements on the Microstructure Characteristics of Hypereutectoid Rails
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作者 戴宇恒 ZHAO Wenqian +1 位作者 包喜荣 陈林 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第3期682-688,共7页
We performed thermal simulation experiments of double-pass deformation of hypereutectoid rails with different microalloying elements at a cooling rate of 1℃/s and deformation of 80%to explore the influence of rare-ea... We performed thermal simulation experiments of double-pass deformation of hypereutectoid rails with different microalloying elements at a cooling rate of 1℃/s and deformation of 80%to explore the influence of rare-earth and microalloying elements on the structure of hypereutectoid rails and optimize the composition design of hypereutectoid rails.Scanning electron microscopy,transmission electron microscopy,X-ray diffraction,and other characterization techniques were employed to quantitatively analyzed the effects of different microalloying elements,including rare-earth elements,on pearlite lamellar spacing,cementite characteristics,and dislocation density.It was found that the lamellar spacing was reduced by adding various microalloying elements.Cementite lamellar thickness decreased with the refinement of pearlite lamellar spacing while the cementite content per unit volume increased.Local cementite spheroidization,dispersed in the ferrite matrix in granular form and thus playing the role of dispersion strengthening,was observed upon adding cerium(Ce).The contributions of dislocation density to the alloy strength of four steel sheet samples with and without the addition of nickel,Ce,and Ce–copper(Cu)composite were 26,27,32,and 37 MPa,respectively,indicating that the Ce–Cu composite had the highest dislocation strengthening effect.The Ce–Cu composite has played a meaningful role in the cementite characteristics and dislocation strengthening,which provides a theoretical basis for optimizing the composition design of hypereutectoid rails in actual production conditions. 展开更多
关键词 microalloying elements rare earth hypereutectoid rail CEMENTITE DISLOCATION
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Geochemical characterization of rare earth elements in sediment profiles from the Oualida lagoon(Morocco)
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作者 Nezha Mejjad Abdelmourhit Laissaoui +2 位作者 Ouafa El Hammoumi Ahmed Fekri Hamid Amsil 《Acta Geochimica》 EI CAS CSCD 2023年第6期1051-1064,共14页
The present work assesses the temporal distribution pattern and geochemical changes of rare earth elements and Yttrium, Scandium, Thorium, and Uranium delivery into the Oualidia lagoon. Two sediment cores were retriev... The present work assesses the temporal distribution pattern and geochemical changes of rare earth elements and Yttrium, Scandium, Thorium, and Uranium delivery into the Oualidia lagoon. Two sediment cores were retrieved from the Oualidia lagoon and analyzed using neutron activation analysis. The results indicated that heavy rare earth elements are slightly enriched the sediment cores over light rare earth elements. The highest values of REEs were recorded in the top layers of the cores and depleted with depth, suggesting a possible change in factors controlling their accumulation, including mechanical, chemical, and environmental parameters such as weathering intensity, grain size, and Fe-Mn oxides. The sediments display positive Ce anomalies, which are probably related to the submarine weathering process and detrital input. Noting also the variation of hydrodynamics conditions and confinement of the upstream part of the lagoon played a key role in changing the sediment origins.Thus, further investigation of REEs origin in the Oualidia lagoon sediment is required to identify their sources,provenances, and the factors controlling their spatial and vertical distributions. However, these results provide baseline data of occurring changes in REEs geochemical composition and constitute a typical study case to understand the link between sedimentary and geochemistry processes in a lagoonal ecosystem. 展开更多
关键词 Geochemical characterization rare earth elements SEDIMENT Oualidia lagoon
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