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Association between intra-pancreatic fat deposition and diseases of the exocrine pancreas: A narrative review 被引量:1
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作者 Jing Ye Jian-Guo Wang +2 位作者 Rong-Qiang Liu Qiao Shi Wei-Xing Wang 《World Journal of Gastroenterology》 SCIE CAS 2025年第2期27-41,共15页
Intrapancreatic fat deposition(IPFD)has garnered increasing attention in recent years.The prevalence of IPFD is relatively high and associated with factors such as obesity,age,and sex.However,the pathophysiological me... Intrapancreatic fat deposition(IPFD)has garnered increasing attention in recent years.The prevalence of IPFD is relatively high and associated with factors such as obesity,age,and sex.However,the pathophysiological mechanisms underlying IPFD remain unclear,with several potential contributing factors,including oxida-tive stress,alterations in the gut microbiota,and hormonal imbalances.IPFD was found to be highly correlated with the occurrence and prognosis of exocrine pan-creatic diseases.Although imaging techniques remain the primary diagnostic approach for IPFD,an expanding array of biomarkers and clinical scoring systems have been identified for screening purposes.Currently,effective treatments for IPFD are not available;however,existing medications,such as glucagon-like peptide-1 receptor agonists,and new therapeutic approaches explored in animal models have shown considerable potential for managing this disease.This paper reviews the pathogenesis of IPFD,its association with exocrine pancreatic disea-ses,and recent advancements in its diagnosis and treatment,emphasizing the significant clinical relevance of IPFD. 展开更多
关键词 Intrapancreatic fat deposition Pancreatic steatosis Nonalcoholic fatty pancreas disease PANCREATITIS Pancreatic cancer
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High-inclination WO_(3)Deposition Enabled Fast-response Aqueous Zinc-ion Electrochromism 被引量:1
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作者 CHEN Shuo XING Kaixiao +6 位作者 LYU Ying YAO Xinxin LI Pan GUO Xiaoyang WANG Tienan LI Xiaotian LIU Xingyuan 《发光学报》 北大核心 2025年第6期1082-1094,共13页
Aqueous zinc-ion electrochromic(EC)technology,boasting the capability to fulfill both safety and cost-ef⁃fectiveness requirements,is garnering extensive attention in various application areas including smart windows,t... Aqueous zinc-ion electrochromic(EC)technology,boasting the capability to fulfill both safety and cost-ef⁃fectiveness requirements,is garnering extensive attention in various application areas including smart windows,thermal management,displays,and camouflage.However,typical inorganic EC materials,such as tungsten oxides(WO_(3)),of⁃ten suffer from slow ion diffusion kinetics and limited optical contrast within the aqueous Zn^(2+)electrolyte because of the large size and strong Coulombic interactions of the Zn^(2+),which limits their wide applicability.Here,ordered WO_(3)nanowire films,constructed by a one-step grazing angle deposition method,is demonstrated to boost the response speed and optical contrast during EC phenomena.Compared with dense films,the ordered WO_(3)nanowire films with a porosity of 44.6%demonstrate anti-reflective property and excellent comprehensive EC performance,including fast response time(3.6 s and 1.2 s for coloring and bleaching,respectively),large optical contrast(66.6%at 700 nm)and high col⁃oration efficiency(64.3 cm^(2)·C^(-1)).A large-area prototype EC device(17 cm×12 cm)with fast color-switching is also successfully achieved.Mechanistic studies show that the improved performance is mainly due to the ordered porous nanowire structures,which provides direct electron transfer paths and sufficient interfacial contacts,thus simultaneously enhancing the electrochemical activity and fast redox kinetics.This study provides a simple and effective strategy to im⁃prove the performance of tungsten oxide-based aqueous zinc ion EC materials and devices. 展开更多
关键词 electrochromic WO_(3) aqueous Zn^(2+)electrolyte ordered nanowires glancing angle deposition
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Machine learning of pyrite geochemistry reconstructs the multi-stage history of mineral deposits 被引量:1
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作者 Pengpeng Yu Yuan Liu +5 位作者 Hanyu Wang Xi Chen Yi Zheng Wei Cao Yiqu Xiong Hongxiang Shan 《Geoscience Frontiers》 2025年第3期81-93,共13页
The application of machine learning for pyrite discrimination establishes a robust foundation for constructing the ore-forming history of multi-stage deposits;however,published models face challenges related to limite... The application of machine learning for pyrite discrimination establishes a robust foundation for constructing the ore-forming history of multi-stage deposits;however,published models face challenges related to limited,imbalanced datasets and oversampling.In this study,the dataset was expanded to approximately 500 samples for each type,including 508 sedimentary,573 orogenic gold,548 sedimentary exhalative(SEDEX)deposits,and 364 volcanogenic massive sulfides(VMS)pyrites,utilizing random forest(RF)and support vector machine(SVM)methodologies to enhance the reliability of the classifier models.The RF classifier achieved an overall accuracy of 99.8%,and the SVM classifier attained an overall accuracy of 100%.The model was evaluated by a five-fold cross-validation approach with 93.8%accuracy for the RF and 94.9%for the SVM classifier.These results demonstrate the strong feasibility of pyrite classification,supported by a relatively large,balanced dataset and high accuracy rates.The classifier was employed to reveal the genesis of the controversial Keketale Pb-Zn deposit in NW China,which has been inconclusive among SEDEX,VMS,or a SEDEX-VMS transition.Petrographic investigations indicated that the deposit comprises early fine-grained layered pyrite(Py1)and late recrystallized pyrite(Py2).The majority voting classified Py1 as the VMS type,with an accuracy of RF and SVM being 72.2%and 75%,respectively,and confirmed Py2 as an orogenic type with 74.3% and 77.1%accuracy,respectively.The new findings indicated that the Keketale deposit originated from a submarine VMS mineralization system,followed by late orogenic-type overprinting of metamorphism and deformation,which is consistent with the geological and geochemical observations.This study further emphasizes the advantages of Machine learning(ML)methods in accurately and directly discriminating the deposit types and reconstructing the formation history of multi-stage deposits. 展开更多
关键词 Machine learning Random forest Support vector machine PYRITE Multi-stage genesis Keketale deposit
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Heterogeneous interfaces of aluminum bronze/Inconel 718 dissimilar alloys under different wire arc directed energy deposition sequences 被引量:1
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作者 Tianxing Chang Xuewei Fang +4 位作者 You Zhou Hongkai Zhang Naiyuan Xi Shahid Ghafoor Ke Huang 《International Journal of Extreme Manufacturing》 2025年第1期368-381,共14页
The layer-by-layer deposition strategy of additive manufacturing makes it ideal to fabricate dissimilar alloy components with varying functionality,which has promising application potential in a large number of indust... The layer-by-layer deposition strategy of additive manufacturing makes it ideal to fabricate dissimilar alloy components with varying functionality,which has promising application potential in a large number of industrial areas.In this study,two components composed of ERCuAl-A2 aluminum bronze(CuAl9)and Inconel 718 nickel-based superalloy were fabricated with different deposition orders by wire-arc directed energy deposition.Subject to changes in heat input and thermophysical properties of the substrate,the transition region of the deposited Cu-Ni component with the bottom half of CuAl9 and the top half of Inconel 718 is narrow and serrated.This region features a laminated intermetallic compound layer due to the convection and rapid cooling in the molten pool.In contrast,the Ni-Cu component deposited in the opposite order exhibits a 2 mm gradient transition zone.Within this region,a large number of diverse precipitates were found as well as regional variations in grain size due to the multi-layer partial remelting.Both two components show strong bonds and their tensile specimens tested along the vertical direction always fracture at the softer CuAl9 side.Excellent tensile properties along the horizontal direction were obtained for Cu-Ni(Ultimate tensile strength:573 MPa,yield stress:302 MPa,elongation:22%),while those of Ni-Cu are much lower due to the existence of the solidification cracks in the transition zone.The results from this study provide a reference for the additive manufacturing of Cu/Ni dissimilar alloy components,as well as their microstructure and mechanical properties control. 展开更多
关键词 wire-arc directed energy deposition dissimilar alloys microstructure aluminum bronze nickel-based super-alloy
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Heterophase interfacial strengthening mechanism in CrNiCux medium-entropy alloys fabricated by laser-directed energy deposition 被引量:1
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作者 Wei Feng Zhixin Xia +5 位作者 Jixin Hou Tao Jiang Zhonghan Liu Zhenxuan Xie Chaohui Zhu Yunhe Yu 《Journal of Materials Science & Technology》 2025年第3期269-281,共13页
The unique structure and formation mechanism of medium-entropy alloys(MEAs)generally result in bet-ter comprehensive properties than traditional alloys.However,the strength-ductility trade-offremains a bottleneck,whic... The unique structure and formation mechanism of medium-entropy alloys(MEAs)generally result in bet-ter comprehensive properties than traditional alloys.However,the strength-ductility trade-offremains a bottleneck,which limits their applications.In this study,we designed novel high-performance CrNiCu x MEAs with a heterophase composition by incorporating a Cu-rich phase,and they were fabricated using laser-directed energy deposition(LDED).The results show that synergistic strengthening from multiple phases significantly improved the mechanical properties of the alloys,resulting in a tensile strength of 675 MPa and a ductility of 34.4%,demonstrating an excellent combination of high tensile strength and ductility.The improved mechanical properties of the CrNiCu x medium-entropy alloys are primarily due to the heterophase interfacial strengthening mechanism.In the alloy,numerous semi-coherent and coher-ent interfaces formed between the Cr-rich phase,Cu-rich phase,and the matrix,creating extensive lattice distortions at the interfaces.An increase in the Cu-rich phase content promoted the interaction between phases,enhancing the strain energy of the alloy and the barrier strength of the interfaces.The calcu-latedτint values,ranging from approximately 5.92-6.69 GPa,are significantly higher than those found in traditional alloys,providing a benchmark for designing new high-performance medium-entropy alloys. 展开更多
关键词 Laser-directed energy deposition CrNiCu x Mechanical properties Heterophase interfacial strengthening
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Microstructure evolution of laser directed energy deposition process prepared CNTs/WE43 composites during solution and aging treatment 被引量:1
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作者 Lyuyuan Wang Zhaodian Wang +3 位作者 Lei Zhao Yuan Chen Yangfan Fu Dongsheng Wu 《Journal of Magnesium and Alloys》 2025年第7期3357-3372,共16页
Solution and aging treatment were conducted on the laser directed energy deposition(LDED)-prepared carbon nanotubes(CNTs)-reinforced WE43(CNTs/WE43)layers to optimize their microstructure and surface properties in thi... Solution and aging treatment were conducted on the laser directed energy deposition(LDED)-prepared carbon nanotubes(CNTs)-reinforced WE43(CNTs/WE43)layers to optimize their microstructure and surface properties in this study.The microstructure of the WE43 and CNTs/WE43 layers was systematically compared.The dissolution of divorced eutectics at the grain boundaries was retarded by CNTs during solution treatment.The spot segregation composed of Mg_(24)Y_(5),CNTs,and Zr cores in the solution treated CNTs/WE43 layer presented a slight decreasing in Y content.The grain growth of both types of layers underwent three stages:slow,rapid,and steady-state.The significant inhibitory effect of CNTs on the grain growth of the LDED WE43 matrix was more pronounced than the promoting effect of temperature,resulting in a 47%increase at 510℃ and a 35%increase at 540℃ in the grain growth exponent compared to the WE43 layers at 510℃.During the subsequent aging treatment at 225℃,the precipitation sequences from plate-shaped β″to plate-shaped and globular β′ were observed in both types of layers.CNTs can facilitate an increase in the nucleation rate of precipitates,but without accelerating precipitation hardening rate.The long and short diameters of the precipitates in peak-aged state were decreased by 48.5%and 43.1%by addition of CNTs,respectively.The wear resistance of both the WE43 and CNTs/WE43 layers can be significantly enhanced through solution and aging treatment.The enhancement in wear resistance for the CNTs/WE43 layers is considerably greater than that of the WE43 layers. 展开更多
关键词 Laser directed energy deposition Cnts-reinforced we43 composite Heat treatment Microstructure evolution
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New progresses of fine-grained sediment gravity-flow deposits and their importance for unconventional shale oil and gas plays 被引量:1
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作者 Tian Yang Ying-Lin Liu 《Petroleum Science》 2025年第1期1-15,共15页
Fine-grained sediments are widely distributed and constitute the most abundant component in sedi-mentary systems,thus the research on their genesis and distribution is of great significance.In recent years,fine-graine... Fine-grained sediments are widely distributed and constitute the most abundant component in sedi-mentary systems,thus the research on their genesis and distribution is of great significance.In recent years,fine-grained sediment gravity-flows(FGSGF)have been recognized as an important transportation and depositional mechanism for accumulating thick successions of fine-grained sediments.Through a comprehensive review and synthesis of global research on FGSGF deposition,the characteristics,depositional mechanisms,and distribution patterns of fine-grained sediment gravity-flow deposits(FGSGFD)are discussed,and future research prospects are clarified.In addition to the traditionally recognized low-density turbidity current and muddy debris flow,wave-enhanced gravity flow,low-density muddy hyperpycnal flow,and hypopycnal plumes can all form widely distributed FGSGFD.At the same time,the evolution of FGSGF during transportation can result in transitional and hybrid gravity-flow deposits.The combination of multiple triggering mechanisms promotes the widespread develop-ment of FGSGFD,without temporal and spatial limitations.Different types and concentrations of clay minerals,organic matters,and organo-clay complexes are the keys to controlling the flow transformation of FGSGF from low-concentration turbidity currents to high-concentration muddy debris flows.Further study is needed on the interaction mechanism of FGSGF caused by different initiations,the evolution of FGSGF with the effect of organic-inorganic synergy,and the controlling factors of the distribution pat-terns of FGSGFD.The study of FGSGFD can shed some new light on the formation of widely developed thin-bedded siltstones within shales.At the same time,these insights may broaden the exploration scope of shale oil and gas,which have important geological significances for unconventional shale oil and gas. 展开更多
关键词 Fine-grained sediment gravity-flow depositional mechanism Transportation and evolution Distribution pattern Shale oil and gas
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Impact of Pollutant Concentration and Particle Deposition on the Radiative Flow of Casson-Micropolar Fluid between Parallel Plates
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作者 Ghaliah Alhamzi Badr Saad T.Alkahtani +2 位作者 Ravi Shanker Dubey Vinutha Kalleshachar Neelima Nizampatnam 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期665-690,共26页
Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental management.Determining the effectiveness of treatment methods in reducing po... Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental management.Determining the effectiveness of treatment methods in reducing pollution scales is made easier by analysing waste discharge concentrations.The waste discharge concentration analysis is useful for assessing how effectively wastewater treatment techniques reduce pollution levels.This study aims to explore the Casson micropolar fluid flow through two parallel plates with the influence of pollutant concentration and thermophoretic particle deposition.To explore the mass and heat transport features,thermophoretic particle deposition and thermal radiation are considered.The governing equations are transformed into ordinary differential equations with the help of suitable similarity transformations.The Runge-Kutta-Fehlberg’s fourthfifth order technique and shooting procedure are used to solve the reduced set of equations and boundary conditions.The integration of a neural network model based on the Levenberg-Marquardt algorithm serves to improve the accuracy of predictions and optimize the analysis of parameters.Graphical outcomes are displayed to analyze the characteristics of the relevant dimensionless parameters in the current problem.Results reveal that concentration upsurges as the micropolar parameter increases.The concentration reduces with an upsurge in the thermophoretic parameter.An upsurge in the external pollutant source variation and the local pollutant external source parameters enhances mass transport.The surface drag force declines for improved values of porosity and micropolar parameters. 展开更多
关键词 Micropolar fluid thermal radiation porous medium thermophoretic particle deposition waste discharge concentration
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Rare Earth Oxide Surface Modification of Porous SiO_(2) Film Prepared by Atomic Layer Deposition
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作者 JIN Jianfei LÜLin +3 位作者 LI Ying YAN Lu CAO Yunzhen LI Wei 《无机材料学报》 北大核心 2025年第9期1029-1036,I0003,共9页
Broadband transparent films play a pivotal role in various applications such as lenses and solar cells,particularly porous structured transparent films exhibit significant potential.This study investigates a porous Si... Broadband transparent films play a pivotal role in various applications such as lenses and solar cells,particularly porous structured transparent films exhibit significant potential.This study investigates a porous SiO_(2) refractive index gradient anti-reflective film prepared by atomic layer deposition(ALD).A porous SiO_(2) film with gradual porosity was obtained by phosphoric acid etching of Al_(2)O_(3)/SiO_(2) multilayers with gradient Al2O3 ratios,achieving a gradual decrease in refractive index from the substrate to the surface.The film exhibited an average transmittance as high as 97.8%within the wavelength range from 320 nm to 1200 nm.The environmental adaptability was further enhanced by surface modification using rare earth oxide(REO)La_(2)O_(3),resulting in formation of a lotus leaf-like structure and achieving a water contact angle of 100.0°.These data proved that the modification significantly improved hydrophobic self-cleaning capability while maintaining exceptional transparency of the film.The surface structure of the modified film remained undamaged even after undergoing wipe testing,demonstrating its excellent surface durability. 展开更多
关键词 porous SiO_(2) rare earth oxide atomic layer deposition anti-reflective SELF-CLEANING
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Early Crack Propagation Behavior of Laser Metal Deposited Ti-6Al-4V Alloy Under High Cycles Fatigue Loading
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作者 Li Yanping Huang Wei +3 位作者 He Yan Xu Feng Zhao Sihan Guo Weiguo 《稀有金属材料与工程》 北大核心 2025年第1期62-75,共14页
The crack initiation and early propagation are of great significance to the overall fatigue life of material.In order to investigate the anisotropic fracture behavior of laser metal deposited Ti-6Al-4V alloy(LMD Ti64)... The crack initiation and early propagation are of great significance to the overall fatigue life of material.In order to investigate the anisotropic fracture behavior of laser metal deposited Ti-6Al-4V alloy(LMD Ti64)during the early stage,the fourpoint bending fatigue test was carried out on specimens of three different directions,as well as the forged specimens.The results indicate the anisotropic crack initiation and early propagation of LMD Ti64.The direction perpendicular to the deposition direction exhibits a better fatigue resistance than the other two.The crack initiation position and propagation path are dominated by the microstructure in the vicinity of U-notch.LMD Ti64 has a typical small crack effect,and the early crack propagation velocities in three directions are similar.Affected by the slip system of LMD Ti64,secondary cracks frequently occur,which are often found to have an angle of 60°to the main crack.The electron backscatter diffraction analysis indicates that LMD Ti64 has preferred orientations,i.e.,strong 0001//Z texture and 001//Z texture.Their crystallographic orientation will change as the direction of columnarβgrains turns over,resulting in the fatigue anisotropy of LMD Ti64 in crack initiation and early crack propagation process. 展开更多
关键词 fatigue resistance crack propagation behavior microstructure laser metal deposit TI-6AL-4V ANISOTROPY
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Effect of Rare Earth on Microstructure and Properties of Deposited Metal in Submerged Arc Welding of 1000 MPa Grade High-Strength Steel
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作者 Li Chunjian Xu Kai +5 位作者 Feng Wei Song Changhong Zhang Qingsu Hao Qianyu Zheng Yongqiang Guo Xuchao 《稀有金属材料与工程》 北大核心 2025年第11期2729-2738,共10页
The optimization of deposited metal properties through the addition of rare earth elements to welding materials was explored.Utilizing optical microscope,scanning electron microscope,energy dispersive spectroscope,and... The optimization of deposited metal properties through the addition of rare earth elements to welding materials was explored.Utilizing optical microscope,scanning electron microscope,energy dispersive spectroscope,and X-ray diffractometer,combined with software tools like Matlab,Image-Pro Plus,and CHANNEL5,the influence mechanism of rare earth element addition on the strength,toughness,and inclusions of deposited metal in 1000 MPa grade high-strength steel was investigated.The results indicate that the incorporation of rare earth elements enhances the weldability of the welding materials.With the addition of rare earth elements,the tensile strength of the deposited metal increases from 935 MPa to 960 MPa.However,further addition leads to a decrease in tensile strength,while the yield strength continuously increases by 8.5%-17.2%.The addition of appropriate amounts of rare earth elements results in an increase in acicular ferrite and retained austenite content,as well as grain refinement in the deposited metal,leading to 8.5%-24.3% and 15.6%-42.2% enhancement in impact energy at−40℃ and−60℃,respectively.Additionally,the proper addition of rare earth elements modifies the inclusions and generates fine and dispersed composite inclusions that bond better with the matrix,thereby optimizing the properties of the deposited metal through various mechanisms.Adding an appropriate amount of rare earth elements can significantly enhance the properties of the deposited metal in 1000 MPa grade high-strength steel,and improve the match between high strength and toughness,meeting the demands for high-strength steel used in hydropower applications. 展开更多
关键词 1000 MPa grade high-strength steel deposited metal submerged arc welding rare earth element INCLUSIONS
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The low-temperature deposition of a zincophilic carbon layer on the Zn foil for long-life zinc metal batteries
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作者 LI Chun-yu ZHANG Ming-hui +2 位作者 LANG Xin-yue CHEN Ye DONG Yan-feng 《新型炭材料(中英文)》 北大核心 2025年第1期178-187,共10页
Aqueous zinc metal batteries(ZMBs)which are environmentally benign and cheap can be used for grid-scale energy storage,but have a short cycling life mainly due to the poor reversibility of zinc metal anodes in mild aq... Aqueous zinc metal batteries(ZMBs)which are environmentally benign and cheap can be used for grid-scale energy storage,but have a short cycling life mainly due to the poor reversibility of zinc metal anodes in mild aqueous electrolytes.A zincophilic carbon(ZC)layer was deposited on a Zn metal foil at 450°C by the up-stream pyrolysis of a hydrogen-bonded supramolecular substance framework,as-sembled from melamine(ME)and cyanuric acid(CA).The zincophilic groups(C=O and C=N)in the ZC layer guide uniform zinc plating/stripping and eliminate dendrites and side reactions.so that assembled symmetrical batteries(ZC@Zn//ZC@Zn)have a long-term service life of 2500 h at 1 mA cm^(−2) and 1 mAh cm^(−2),which is much longer than that of bare Zn anodes(180 h).In addition,ZC@Zn//V2O5 full batteries have a higher capacity of 174 mAh g^(−1) after 1200 cycles at 2 A g^(−1) than a Zn//V_(2)O_(5) counterpart(100 mAh g^(−1)).The strategy developed for the low-temperat-ure deposition of the ZC layer is a new way to construct advanced zinc metal anodes for ZMBs. 展开更多
关键词 Aqueous zinc metal batteries Zinc metal anodes Low-temperature deposition Zincophilic carbon layer High performance
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Geology,mineralization and model of the giant Maoping carbonate-hosted Pb-Zn deposit(5 Mt),South China
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作者 Ye He Bang-Tao Sun +5 位作者 Hai-Peng Wang Jia-Xi Zhou Yan-Jun Li Foteini Drakou Kai Luo Saleh Ibrahim Bute 《China Geology》 2025年第2期431-453,I0011-I0047,共60页
The giant Upper Yangtze Pb-Zn metallogenic province,also known as the Sichuan-Yunnan-Guizhou(SYG)Pb-Zn province hosting>500 carbonate-hosted epigenetic Pb-Zn deposits that contain>20 Mt Pb+Zn base metal reserves... The giant Upper Yangtze Pb-Zn metallogenic province,also known as the Sichuan-Yunnan-Guizhou(SYG)Pb-Zn province hosting>500 carbonate-hosted epigenetic Pb-Zn deposits that contain>20 Mt Pb+Zn base metal reserves.The giant Maoping Pb-Zn deposit is the second largest deposit in this province and owns>5 Mt Pb+Zn metal reserves with ore grades of 12 wt.%-30 wt.%Pb+Zn.Such large tonnages and high grades make it among the top 100 similar mineral deposits in the world.The ore bodies are predominantly located within the strata of the Upper Devonian(Zaige Formation)and Lower(Baizuo Formation)-Upper(Weining Formation)Carboniferous.The principal ore minerals consist of galena(Gn),sphalerite(Sp),and pyrite(Py),while the primary gangue minerals include dolomite(Dol),calcite(Cal),and quartz(Qtz).Three mineralization stages of carbonate minerals have been identified:(1)pre-sulfide stage 1,(2)syn-sulfide stage 2,and(3)post-sulfide stage 3.Trace elements and C-O-Sr isotopes of three stages’carbonate minerals,together with S-Pb isotopes of sulfides,revealing that the metamorphic basement rocks played the role of the metal source during the early stage of Pb-Zn mineralization,whereas the metal contribution of the sedimentary wall rocks found to be more prominent during the late stage of Pb-Zn mineralization.In addition,the dissolution of marine carbonate rocks and CO_(2)degassing may have also played an important role in the formation of the Maoping deposit.Furthermore,syn-sulfide stage 2 calcite has a U-Pb age of 214±20 Ma obtained by LA-ICPMS in-situ analyses,suggesting that the hydrothermal mineralization occurred during the Triassic.Our study proposes a new coupled metallogenic model of fluid-structure-lithology assemblage and provides new insights about the formation and evolution of the Maoping deposit with significant implication for understanding and exploration of similar Pb-Zn deposits worldwide. 展开更多
关键词 Ore deposit geology Mineralogy Geochemistry Geochronology Ore deposit formation and evolution Ore-forming model Maoping carbonate-hosted Pb-Zn deposit SW China
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Review of online quality control for laser directed energy deposition(LDED)additive manufacturing
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作者 Long Ye Hao Xue +6 位作者 Zhaosheng Li Yichang Zhou Guangyu Chen Fangda Xu Ruslan Melentiev Stephen Newman Nan Yu 《International Journal of Extreme Manufacturing》 2025年第6期152-196,共45页
Laser directed energy deposition(LDED)is an emerging branch of metal-based additive manufacturing(AM)processes,offering unprecedented capabilities for high-performance fabrication with complex geometries and near-net ... Laser directed energy deposition(LDED)is an emerging branch of metal-based additive manufacturing(AM)processes,offering unprecedented capabilities for high-performance fabrication with complex geometries and near-net shapes.This technology is gathering increasing attention from industries such as biomedical,automotive,and aerospace.However,achieving consistent part quality and desired material properties is challenging due to intricate processing parameters and potential process defects such as dynamic melt-pool behavior and localized heat accumulation.This paper reviews recent advances in on-line quality control,focusing on in-situ measurement and closed-loop control for efficient assurance of LDED-fabricated parts.The quality principles,encompassing accuracy and material performance,are summarized to lay a foundation for understanding the mechanisms of quality defects and influencing factors.This review explores and thoroughly compares advancements in indirect process measurements,such as optical,thermal,and acoustic monitoring with direct quality measurements,including laser-line scanning and operando synchrotron X-ray imaging.Depending on the sensing techniques,this paper highlights a hierarchical control strategy for adaptive parameter regulation on intra-layer and inter-layer scales.The requirements and performance of various state-of-the-art controllers are critically compared to indicate their suitable applications.The importance of machine learning in detecting process anomalies and predicting build quality based on sensory signals is also outlined.Future directions are proposed towards adaptive,automated,and intelligent quality control,with a focus on multi-modal monitoring,physics-informed neural networks for interpretable analysis,and multi-objective control applications. 展开更多
关键词 additive manufacturing directed energy deposition laser deposition process monitoring quality defects quality control machine learning
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What Controls the Distribution of Ore Veins in Quartz Vein-Type Tungsten Deposits:Constrains from Fan-Shaped Mineralization in SE China
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作者 Gui-Cong Fang Deng-Hong Wang +5 位作者 Fu-Qiang Yang Zhan-Xu Ni Chang-Shuai Huang Ping Wang Meng Feng Zuo-Hai Feng 《Journal of Earth Science》 2025年第5期2023-2037,共15页
Quartz vein-type tungsten deposits are a common W deposit type.Their ore vein distribution was previously considered to be controlled by regional horizontal tectonic stress.In this paper,14 tungsten deposits with fan-... Quartz vein-type tungsten deposits are a common W deposit type.Their ore vein distribution was previously considered to be controlled by regional horizontal tectonic stress.In this paper,14 tungsten deposits with fan-shaped mineralization in SE China are summarized,and the relations between their ore veins and granite and the ore-forming structural stress field are analyzed.These deposits have a post-magmatic hydrothermal genesis and involve the formation of two sets of veins with similar strike and opposite dips at the top of the ore-causative granite bodies,forming a vertical fan-shaped profile.Their ore veins were coeval with the underlying granite bodies,and generally extend along the long axis of the granite.In such fan-shaped ore formation,the stress is highly focused at the top of the granite and gradually weakens outward.The maximum principal stress(σ1)is perpendicular to the granite contact surface,and radiates outward from the pluton.Meanwhile,the minimum principal stress(σ3)forms an arc-shaped band parallel to the contact surface.Our findings,together with published numerical modeling indicate that the emplacement dynamics of granitic magma(rather than regional horizontal tectonic stress)are essential controls on the distribution of ore veins in quartz vein-type tungsten deposits. 展开更多
关键词 quartz vein-type tungsten deposit fan-shaped mineralization ore-forming structural stress emplacement dynamic GRANITE SE China mineral deposits geochemistry
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Coupled Dissolution-Precipitation Mineralized Process in Bailongshan Li Deposit,West Kunlun(NW China),Evidenced by the Mineralogy of Cassiterite,Columbite-Group Minerals and Elbaite
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作者 Tao Hong ZhangZhang +2 位作者 Zeli Jiang Mingxi Hu Pengli Jiao 《Journal of Earth Science》 2025年第3期1033-1050,共18页
Coupled dissolution-precipitation is one of the critical processes influencing the mineralogical and geochemical evolution of pegmatites.This mechanism involves the simultaneous dissolution of primary mineral phases a... Coupled dissolution-precipitation is one of the critical processes influencing the mineralogical and geochemical evolution of pegmatites.This mechanism involves the simultaneous dissolution of primary mineral phases and the precipitation of secondary phases,driven by changes in the chemical environment,often mediated by hydrothermal fluids.The Bailongshan Li deposit,located in the West Kunlun region of northwest China,is a significant geological formation known for its rich lithium content and associated rare metals such as tantalum,niobium,and tin.This study investigates the coupled dissolution-precipitation processes that have played a crucial role in the mineralization of this deposit,focusing on key minerals,including cassiterite(Cst),columbite-group minerals(CGM),and elbaite(Elb).Using a combination of petrographic analysis,back-scattered electron(BSE)imaging,cathodoluminescence(CL)imaging,and micro X-ray fluorescence(XRF)mapping,we examined the textural and chemical characteristics of these minerals.Our findings reveal intricate patchy zoning patterns and element distributions(indicated by the Nb,Ta,W,Mn,Fe,Hf,Ti for CGM;Hf,Ti Rb,W,Nb,Ta for Cst;Ti,Zn,Fe,W,Hf,Mn,K for Elb)that indicate multiple stages of mineral alteration driven by fluid-mediated processes.The coupled dissolution-precipitation mechanisms observed in the Bailongshan deposit have resulted in significant redistribution and enrichment of economically valuable elements.The study highlights the importance of hydrothermal fluids in altering primary mineral phases and precipitating secondary phases with distinct compositions.These processes not only modified the mineralogical makeup of the pegmatite but also enhanced its economic potential by concentrating rare metals.Signatures of coupled dissolutionprecipitation processes can serve as an essential tool for mineral exploration,guiding the search for high-grade zones within similar pegmatitic formations. 展开更多
关键词 coupled dissolution-precipitation mineralized process West Kunlun MINERALOGY pegmatite Li deposit ore deposits
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Three-Dimensional Prospectivity Modeling of Jinshan Ag-Au Deposit,Southern China by Weights-of-Evidence
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作者 Fan Xiao Qiuming Cheng +1 位作者 Weisheng Hou Frederik P.Agterberg 《Journal of Earth Science》 2025年第5期2038-2057,共20页
To comprehensively utilize the valuable geological map,exploration profile,borehole,and geochemical logging data and the knowledge on the formation of the Jinshan Ag-Au deposit for forecasting the exploration targets ... To comprehensively utilize the valuable geological map,exploration profile,borehole,and geochemical logging data and the knowledge on the formation of the Jinshan Ag-Au deposit for forecasting the exploration targets of concealed ore bodies,three-dimensional Mineral Prospectivity Modeling(MPM)of the deposit has been conducted using the weights-of-evidence(WofE)method.Conditional independence between evidence layers was tested,and the outline results using the prediction-volume(P-V)and Student's t-statistic methods for delineating favorable mineralization areas from continuous posterior probability map were critically compared.Four exploration targets delineated ultimately by the Student's t-statistic method for the discovery of minable ore bodies in each of the target areas were discussed in detail.The main conclusions include:(1)three-dimensional modeling of a deposit using multi-source reconnaissance data is useful for MPM in interpreting their relationships with known ore bodies;(2)WofE modeling can be used as a straightforward tool for integrating deposit model and reconnaissance data in MPM;(3)the Student's t-statistic method is more applicable in binarizing the continuous prospectivity map for exploration targeting than the PV approach;and(4)two target areas within high potential to find undiscovered ore bodies were diagnosed to guide future near-mine exploration activities of the Jinshan deposit. 展开更多
关键词 three-dimensional modeling mineral prospectivity mapping exploration targeting WEIGHTS-OF-EVIDENCE C-V fractal model Jinshan Ag-Au deposit mineral deposits economic geology
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Stepwise zinc deposition for high-capacity and long-life anode in aqueous zinc-ion batteries
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作者 Weili Xie Kaiyue Zhu +2 位作者 Weikang Jiang Hanmiao Yang Weishen Yang 《Journal of Energy Chemistry》 2025年第7期427-437,共11页
Rechargeable aqueous zinc-ion batteries(AZIBs)are widely studied for energy storage because of their high safety,low cost and high energy/power density.However,the practical application of AZIBs is limited by dendrite... Rechargeable aqueous zinc-ion batteries(AZIBs)are widely studied for energy storage because of their high safety,low cost and high energy/power density.However,the practical application of AZIBs is limited by dendrite formation at the zinc anode under high-depth deposition,which results in reduced cycle life and overall performance.Herein,we propose an effective and scalable stepwise deposition approach that integrates uniform nucleation and dense growth through the construction of ultrathin ZnO nanofiber arrays(ZONAs)on the zinc anode surface,along with the introduction of an anionic surfactant(AS)into the electrolyte.This approach yields a uniform,dense and dendrite-free Zn anode during cycling,maintaining stable cycling for 2100 h under a high deposition depth of 10 mAh cm^(-2)at an extremely high current density of 10 m A cm^(-2).Additionally,full cells using MnO_(2)cathodes exhibit stable cycling for 6000cycles at 5 A g^(-1),with a capacity retention of 75%.Furthermore,the pouch-type cell with an area of90 cm2delivers a capacity of 60 m Ah and maintains stable cycling for 540 cycles at 200 mA,highlighting its strong potential for scalability. 展开更多
关键词 Stepwise deposition Zinc oxide nanofiber arrays Anionic surfactant Dendrite-free anode High deposition capacity
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Zinc and cadmium isotope signatures:Insights into ore genesis and exploration strategies at the Xiaohongshilazi Pb-Zn-(Ag)deposit,Northeast China
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作者 Huchao Ma Da Wang +2 位作者 Ryan Mathur Gaotian Wang Feng Bai 《Geoscience Frontiers》 2025年第4期85-104,共20页
The Jizhong-Yanbian Cu-Mo-Au-Pb-Zn polymetallic metallogenic belt is a major nonferrous and precious metal resource base in Northeastern China.The genesis of ore deposits in this district has remained controversial.To... The Jizhong-Yanbian Cu-Mo-Au-Pb-Zn polymetallic metallogenic belt is a major nonferrous and precious metal resource base in Northeastern China.The genesis of ore deposits in this district has remained controversial.To constrain ore genetic models and provide information for exploration,we conducted precise Zn-Cd isotopic measurements on sphalerite and galena.Theδ^(66)Zn_(AA-ETH)values of galena and sphalerite range from−0.07‰to 0.03‰and−0.68‰to−0.12‰,respectively;and theirδ^(114/110)Cd_(NIST SRM 3108)values vary from−0.96‰to 3.83‰and−0.63‰to 0.77‰,respectively.Our study suggests that the Xiaohongshilazi Pb-Zn-(Ag)deposit should be classified as a Mississippi Valley Type(MVT)-like deposit,because both its geological,sulfide trace elemental,and S-Pb-Fe-Zn-Cd isotopic characteristics are similar to those of the typical MVT deposit,except for the differences of the wall rocks.Rayleigh fractionation during sphalerite precipitation is identified as the primary mechanism for Zn-Cd isotopic variations,which is validated by the Zn-Cd fractionation models from 100℃to 250℃.Finally,we propose an ore prospecting model based on migration pathways of ore-forming fluid and the Zn isotopic fractionation model of sphalerite under 100℃.This model indicates potential resources undiscovered at shallow/peripheral and deep zones of current mining level in both the Eastern and Western Ore Block,with parts of the potential resources having been corroborated by recent drilling.Despite the complexity of mineralization,processes,this study provides new insights into the application of Zn-Cd isotopes in understanding ore genesis and guiding mineral exploration in similar contexts. 展开更多
关键词 Zn-Cdisotopes Reyleigh fractionation MVT-like deposit Ore genesis and exploration Xiaohongshilazi Pb-Zn-(Ag)deposit Northeast China
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Effect of Diagenetic Processes and Depositional Facies on Reservoir Quality of the Eocene Carbonate Sequence(Sakesar Limestone)in the Central Salt Range,Pakistan
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作者 Naveed Rehman Shu Jiang +2 位作者 Syed Haroon Ali Asim Falak Naz Muhammad Tariq 《Journal of Earth Science》 2025年第3期1129-1148,共20页
The effect of depositional facies and diagenesis on the reservoir potential of the Sakesar limestone has been assessed through core plug porosity and permeability data,scanning electron microscope(SEM),and petrographi... The effect of depositional facies and diagenesis on the reservoir potential of the Sakesar limestone has been assessed through core plug porosity and permeability data,scanning electron microscope(SEM),and petrographic study in three stratigraphic sections(Karuli,Badshah Pur,and Sardhai)of Central Salt Range.Field observations reveal three lithofacies:thin-bedded limestone with shale intercalation,thick-bedded nodular limestone,and highly fractured limestone.Based on a petrographic study,six microfacies have been identified:bioclastic mudstone facies(SKF-1),Lockhartia-nummulitic wackestone facies(SKF-2),Assilina-Alveolina packstone facies(SKF-3),Lockhartia-nummulitic packstone facies(SKF-4),Alveolina grainstone facies(SKF-5),and nummulitic grainstone facies(SKF-6).The Sakesar limestone shows various diagenetic changes such as compaction,dissolution,dolomitization,cementation,and fracturing,resulting in different types of pores.Two reservoir zones are identified in the Sakesar limestone:a mud-dominated reservoir in an outer ramp setting with interparticle and micropores and a bioclastic grain-dominated facies in an inner ramp setting with intraskeletal and fracture porosity.The porosity and permeability of grain-dominated facies(8%-30%and 0.8-8 mD)are higher than mud-dominated facies(4%-15%and 0.5-4 mD)due to intraskeletal/intraparticle pores and dolomitization. 展开更多
关键词 porosity permeability DIAGENESIS DOLOMITIZATION MICROFACIES STRATIGRAPHY petroleum deposits
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