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Recent process developments in beneficiation and metallurgy of rare earths:A review

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Journal of Rare Earths 2024年第4期42卷 629-642页

作者： Shaokai cheng Wenbo Li Yuexin han Yongsheng Sun Peng Gao Xiaolong Zhang School of Resources and Civil Engineering Northeastern UniversityShenyang110819China National-local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang110819China

Rare earth elements(REEs)are irreplaceable materials supporting low-carbon technology and equip-ment,and their commercial demand and strategic position are becoming increasingly *** the continuous depletion of rare earth(RE)resources,developing high-efficiency beneficiation and eco-friendly metallurgical processes has attracted widespread *** paper reviews the major minerals exploited for RE production and their deposits,as well as the beneficiation and metallurgical processes of RE ***,monazite,mixed RE ores,and ion-adsorption clays are the main raw materials in the world to ***-bearing ores(except ion-adsorption minerals)are generally beneficiated by flotation,gravity and magnetic separation *** mainstream metallurgical processes for bastnaesite,monazite and mixed RE concentrates are oxidation roasting-HCl leaching,caustic soda decomposition and high-temperature concentrated sulfuric acid roasting,***-adsorption clays are directly processed by in situ leaching-precipitation/solvent *** achieve the sustainable development of RE resources,it is essential to further explore innovative techniques to achievecomprehensive utilization and cleaner production.

关键词： Rare earths Beneficiation processes Metallurgical processes Cleaner production

Discriminative explicit instance selection for implicit discourse relation classification

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Frontiers of Computer Science 2024年第4期18卷 129-138页

作者： Wei SONG Hongfei han Xu han Miaomiao cheng Jiefu GONG Shijin WANG Ting LIU Information Engineering College Capital Normal UniversityBeijing 100048China iFLYTEK AI Research Institute Hefei 230088China Research Center for Social Computing and Information Retrieval Harbin Institute of TechnologyHarbin 150006China

Discourse relation classification is a fundamental task for discourse analysis,which is essential for understanding the structure and connection of *** discourse relation classification aims to determine the relationship between adjacent sentences and is very challenging because it lacks explicit discourse connectives as linguistic cues and sufficient annotated training *** this paper,we propose a discriminative instance selection method to construct synthetic implicit discourse relation data from easy-to-collect explicit discourse *** expanded instance consists of an argument pair and its sense *** introduce the argument pair type classification task,which aims to distinguish between implicit and explicit argument pairs and select the explicit argument pairs that are most similar to natural implicit argument pairs for data *** also propose a simple label-smoothing technique to assign robust sense labels for the selected argument *** evaluate our method on PDTB 2.0 and PDTB *** results show that our method can consistently improve the performance of the baseline model,and achieve competitive results with the state-of-the-art models.

关键词： discourse analysis PDTB discourse relation implicit discourse relation classification data expansion

A Comparative Study on the Post-Buckling Behavior of Reinforced Thermoplastic Pipes(RTPs)Under External Pressure Considering Progressive Failure

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China Ocean Engineering 2024年第2期38卷 233-246页

作者： DING Xin-dong WANG Shu-qing LIU Wen-cheng YE Xiao-han College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China Department of Marine Technology Norwegian University of Science and Technology(NTNU)Trondheim NO-7491Norway

The collapse pressure is a key parameter when RTPs are applied in harsh deep-water *** investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are *** the numerical simulations,the eigenvalue analysis and Riks analysis are combined,in which the Hashin failure criterion and fracture energy stiffness degradation model are used to simulate the progressive failure of composites,and the“infinite”boundary conditions are applied to eliminate the boundary *** for the hydrostatic pressure tests,RTP specimens were placed in a hydrostatic chamber after filled with *** has been observed that the cross-section of the middle part collapses when it reaches the maximum *** collapse pressure obtained from the numerical simulations agrees well with that in the ***,the applicability of NASA SP-8007 formula on the collapse pressure prediction was also *** has a relatively greater difference because of the ignorance of the progressive failure of *** the parametric study,it is found that RTPs have much higher first-ply-failure pressure when the winding angles are between 50°and 70°.Besides,the effect of debonding and initial ovality,and the contribution of the liner and coating are also discussed.

关键词： reinforced thermoplastic pipes post-buckling behavior progressive failure of composites debonding initial ovality

Accelerated aging and frailty in cardiovascular diseases

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Journal of Geriatric Cardiology 2024年第8期21卷 828-830页

作者： Xue-Hua cheng Tao WU Li han Department of Traditional Chinese Medicine Geriatrics Huadong Hospital Affiliated to Fudan UniversityShanghaiChina

Aging is the greatest risk factor for cardiovascular disease(CVD),which is the most common cause of death in European countries.[1]It is estimated that during the period from 2020 to 2022,there were 9.0%more excess deaths from CVD than expected.[2]By 2030,approximately 20%of the population will be aged 65 years and older,and CVD will account for 40%of deaths in this age group,[3]imposing a significant burden on the healthcare system and society as a *** is related to frailty,which represents the dynamic progression of physical and physiological decline in older *** limits an individual’s ability to recover from acute stressors and serves as a predictor of clinical adverse *** the uncertainties in screening,assessing,and managing frailty in clinical practice,emphasizing the connections between frailty,aging,and CVD will provide new insights for the prediction,prevention and management of CVD in the aging population.

关键词： aging prevention prediction

A Possible X-ray Quasi-periodic Oscillation in the Narrow-line Seyfert 1 Galaxy Mrk 142

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Research in Astronomy and Astrophysics 2024年第6期24卷 191-200页

作者： Xiao-Gu Zhong Jian-cheng Wang Yong-yun Chen Xiao-Ling Yu College of Physics and Electronic Engineering Qujing Normal UniversityQujing 655011China yunnan Observatories Chinese Academy of SciencesKunming 650216China

A possible quasi-periodic oscillation(QPO) at frequency 7.045 × 10^(-5) Hz is found in the narrow-line Seyfert 1galaxy Mrk 142 in the data of XMM-Newton collected on 2020 April *** find that the QPO signal is statistically significantly larger than the 5σ level and highly coherent with quality factor Q > 5 at the 0.3–10 keV band by using the method of the Lomb–Scargle Periodogram,the Weighted Wavelet Z-transform and the *** analyze the data in 0.3–0.6 keV,0.6–1 keV,1–3 keV and 3–10 keV energy bands,and find obvious QPO signals at 0.3–0.6 keV and 1–3 keV *** then analyze the time-average spectra and time variability at the QPO frequency of 7.045 × 10^(-5) Hz,and use a model to fit *** find that the QPO signal mainly comes from the X-ray hot corona.

关键词： X-rays:galaxies galaxies:Seyfert accretion accretion disks radiation mechanisms:general

New insight into the role of exosomes in idiopathic membrane nephropathy

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BIOCELL 2024年第1期48卷 21-32页

作者： JIANHONG LIU KAI HE han WANG XIAOHONG cheng Department of Nephrology Shaanxi Provincial Hospital of Traditional Chinese MedicineXian710000China School of BasicMedical Sciences and State Key Laboratory of Southwestern Chinese Medicine Resources Chengdu University of Traditional Chinese MedicineChengdu611137China Department of Pathophysiology West China College of Basic Medical Sciences&Forensic MedicineSichuan UniversityChengdu610041China

Exosomes,nanoscale extracellular vesicles(EVs)derived from the invagination of the endosomal membrane,are secreted by a majority of cell *** carriers of DNA,mRNA,proteins,and microRNAs,exosomes are implicated in regulating biological activities under physiological and pathological ***-derived exosomes,which vary in origin and function,may either contribute to the pathogenesis of disease or represent a potential therapeutic *** nephropathy(MN),an autoimmune kidney disease characterized by glomerular damage,is a predominant cause of nephrotic ***,MN,especially idiopathic membranous nephropathy(IMN),often results in end-stage renal disease(ESRD),affecting approximately 30%of patients and posing a considerable economic challenge to healthcare *** substantial research,therapeutic options remain ineffective at halting IMN progression,underscoring the urgent need for innovative *** evidence has implicated exosomes in IMN’s pathophysiology;Providing a fresh perspective for the discovery of novel biomarkers and therapeutic *** review aims to scrutinize recent developments in exosome-related mechanisms in IMN and evaluate their potential as promising therapeutic targets and diagnostic biomarkers,with the hope of catalyzing further investigations into the utility of exosomes in MN,particularly IMN,ultimately contributing to improved patient outcomes in these challenging disease settings.

关键词： Exosomes Biomarkers Membranous nephropathy Therapeutic targets

Progranulin:A promising biomarker and therapeutic target for fibrotic diseases

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Acta Pharmaceutica Sinica B 2024年第8期14卷 3312-3326页

作者： Fan Yang Ming-han cheng Hai-Feng Pan Jian Gao Pediatric Translational Medicine Institute Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong UniversityShanghai 200000China Department of Ophthalmology the First Affiliated Hospital of Anhui Medical UniversityHefei 230022China Department of Epidemiology and Biostatistics School of Public HealthAnhui Medical UniversityHefei 230022China Inflammation and Immune Mediated Diseases Laboratory of Anhui Province Hefei 230022China

Progranulin(PGRN),a multifunctional growth factor-like protein expressed by a variety of cell types,serves an important function in the physiologic and pathologic processes of fibrotic diseases,including wound healing and the inflammatory *** was discovered to inhibit proinflammation effect by competing with tumor necrosis factor-alpha(TNF-a)binding to TNF ***,excessive tissue repair in the development of inflammation causes tissue *** investigations have indicated the significance of PGRN in regulating inflammatory ***,multiple studies have shown that PGRN was linked to fibrogenesis,and was considered to monitor the formation of fibrosis in multiple organs,including liver,cardiovascular,lung and *** paper is a comprehensive review summarizing our current knowledge of PGRN,from its discovery to the role in *** is followed by an in-depth look at the characteristics of PGRN,consisting of its structure,basic function and intracellular ***,we will discuss the potential of PGRN in the diagnosis and treatment of fibrosis.

关键词： Progranulin Fibrotic disease Fibrosis Inflammation Biomarker Therapeutic target PGRN/TNFR interaction Signaling pathway

Laser welding study of vacuum sintered HUST-1 lunar regolith simulant

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Science China(Technological Sciences) 2024年第9期67卷 2905-2918页

作者： han WenBin DING Lieyun ZHOU cheng ZHOU Yan DANG Fen National Center of Technology Innovation for Digital Construction Huazhong University of Science and TechnologyWuhan 430074China School of Civil and Hydraulic Engineering Huazhong University of Science and TechnologyWuhan 730074China

Efforts are underway to establish a permanent lunar base on the Moon. In situ lunar regolith is anticipated to be useful as a building material after sintering. However, sintering lunar regolith into a large-scale structure presents challenges. Therefore, the key to lunar construction lies in assembling multiple small-sized sintered modules into a stable, large-sized structure. This study explored the feasibility of welding the sintered HUST-1 lunar regolith simulant(HLRS) using a laser device and conducted experiments using lasers of varying power. The microstructure, mineral composition, element distribution, and shear strength of the welded joint were investigated. A few low-melting minerals were fused and vaporized during welding, leading to the generation of thermal decomposition gas. Furthermore, the welded joint exhibited numerous micro-cracks, pores, and bubbles,resulting in reduced weld shear strength. Finally, the influence of laser power on weld shear strength was investigated, revealing that the highest shear strength(15.69 N/cm) was achieved at a laser power of 1000 W. This study demonstrates the feasibility of laser welding of sintered HLRS for the first time, with potential applications in lunar base construction.

关键词： lunar regolith vacuum sintering laser welding weld shear strength lunar base

带有整体单极的Reissner-Nordstrom-AdS黑洞在扩展相空间中的霍金辐射

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物理学报 2024年第2期73卷 104-111页

作者：韩亦文胡成洪云重庆工商大学物理系重庆400067 成都东软学院基础教学学院成都611844

本文研究了带有整体单极的Reissner-Nordstrom-AdS黑洞在扩展相空间中出射粒子的量子隧穿辐射过程.其中,将宇宙学参数视为动态变量而不同于之前研究工作中将其视为常数而忽略其贡献.具体地,在计算出射粒子隧穿率时将宇宙学参数引入计算... 详细信息

本文研究了带有整体单极的Reissner-Nordstrom-AdS黑洞在扩展相空间中出射粒子的量子隧穿辐射过程.其中,将宇宙学参数视为动态变量而不同于之前研究工作中将其视为常数而忽略其贡献.具体地,在计算出射粒子隧穿率时将宇宙学参数引入计算并将其解释为热力学压强.计算结果表明,出射粒子的隧穿率与粒子出射前后黑洞的贝肯斯坦-霍金熵差成正比,辐射谱偏离了纯热谱,该结果与将宇宙学参数视为常数的情况完全相同.这意味着在扩展相空间中可以得到粒子的隧穿概率,并且隧穿过程不依赖于热力学状参量,这一工作自然地进一步将霍金辐射推广到了带有整体单极Reissner-Nordstrom-AdS黑洞扩展相空间中.结果表明,整体单极子尽管影响粒子的动力学行为和热力学量,但并不影响熵变和隧穿率.

关键词：霍金辐射宇宙学参数热力学压强整体单级

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