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Spatiotemporal heterogeneity of magnetic enhancement mechanisms in aeolian deposits on the southern Tibetan Plateau:Implications for paleoclimatic reconstruction in mountainbasin systems
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作者 WANG Haoyu YANG Junhuai +9 位作者 QU Wenxi WANG Linkai ZHANG Canyi LIU Xin TANG Jinmeng GAO Fuyuan CHEN Zixuan WANG Shuyuan FAN Yijiao WU Duo 《Journal of Geographical Sciences》 2026年第1期177-198,共22页
Aeolian deposits across the Yarlung Zangbo River Basin on the southern Tibetan Plateau record the landscape and atmospheric evolution of Earth's Third Pole.The complex mountain-basin system exhibits nonlinear resp... Aeolian deposits across the Yarlung Zangbo River Basin on the southern Tibetan Plateau record the landscape and atmospheric evolution of Earth's Third Pole.The complex mountain-basin system exhibits nonlinear responses to climate forcing,complicating the interpretation of its high-altitude environmental dynamics.Investigating the magnetic enhancement mechanism of aeolian deposits offers an opportunity to decipher climate signals.Our analysis of three aeolian sections from the basin indicates that magnetic minerals are predominantly low-coercivity ferrimagnetic minerals,and grain sizes fine from upper to lower reaches due to climate shifts from arid to humid.Magnetic enhancement in the upper reaches primarily originates from dust input,while dust input and pedogenesis contribute variably over time in the middle and lower reaches.Similar complex patterns occur in the Ili basin,a mountain-basin system in northwestern China.They differ from the Chinese Loess Plateau,where long-distance-transported dust is well-mixed and the pedogenic enhancement model is applied,and desert peripheries where short-distance dust is transported and the dust input model is applied.We summarize the magnetic enhancement mechanisms in various settings and offer a new framework for applying magnetic techniques in paleoclimate reconstruction within global mountain-basin systems,which highlights the need for caution in interpreting their magnetic susceptibility records. 展开更多
关键词 HOLOCENE aeolian deposits magnetic properties climate change Yarlung Zangbo River Basin
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High-temperature oxidation resistance of TiB_(2)coatings on molybdenum produced by molten salt electrophoretic deposition
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作者 Qian Kou Chuntao Ge +6 位作者 Yanlu Zhou Wenjuan Qi Junjie Xu Weiliang Jin Jun Zhang Hongmin Zhu Saijun Xiao 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期282-291,共10页
TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing Ti... TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing TiB_(2)coatings have disadvantages such as high equipment costs,complicated processes,and highly toxic gas emissions.This paper proposes an environmentally friendly method,which requires inexpensive equipment and simple processing,for preparing TiB_(2)coating on molybdenum via electrophoretic deposition within Na3AlF6-based molten salts.The produced TiB_(2)layer had an approximate thickness of 60μm and exhibited high density,outstanding hardness(38.2 GPa)and robust adhesion strength(51 N).Additionally,high-temperature oxidation experiments revealed that,at900℃,the TiB_(2)coating provided effective protection to the molybdenum substrate against oxidation for 3 h.This result indicates that the TiB_(2)coating prepared on molybdenum using molten salt electrophoretic deposition possesses good high-temperature oxidation resistance. 展开更多
关键词 molten salt electrophoretic deposition MOLYBDENUM TiB_(2)coating high-temperature oxidation resistance
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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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The Jalilabad copper deposit in the Tarom-Hashjin magmatic belt,NW Iran:Epithermal or porphyry deposit?Evidence from geology,alteration,geochemistry,fluid inclusions,and stable isotope studies
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作者 Mohammadreza Hosseinzadeh Ali Asadi +3 位作者 Vartan Simmonds Matthew I.Leybourne Mohsen Moayyed Yalda Vahed 《Acta Geochimica》 2025年第6期1186-1213,共28页
The Jalilabad Cu(±Au)deposit lies in the central section of the Tarom-Hashjin Metallogenic Belt,in northern Zanjan Province,NW Iran.Mineralization predominantly occurs within quartz-sulfide veins,veinlets,and bre... The Jalilabad Cu(±Au)deposit lies in the central section of the Tarom-Hashjin Metallogenic Belt,in northern Zanjan Province,NW Iran.Mineralization predominantly occurs within quartz-sulfide veins,veinlets,and breccia zones,primarily hosted by the Eocene volcanic and volcaniclastic units of the Karaj Formation.The mineralization trends NW-SE and is influenced by several strike-slip faults.Chalcopyrite and bornite are the principal hypogene sulfides,with chalcocite and covellite representing the supergene stage.The post-ore stage is characterized by brecciated calcite and quartz.Geochemical analyses show that the monzonite intrusion contains SiO_(2)levels ranging from 69.80 to 70.24 wt.%,K_(2)O+Na_(2)O values between 8.10 and 8.15 wt.%,and K_(2)O/Na_(2)O ratios of 1.36 to 1.61.The intrusion is enriched in light rare earth elements(LREEs)and large-ion lithophile elements(LILEs)while being depleted in high-field-strength elements(HFSEs).A low Hf/Sm ratio indicates an orogenic-related magma,and a low Nb/La ratio points to a depleted mantle source.Microthermometric studies of three quartz types reveal moderate to high formation temperatures(195.4-322.7℃)and salinities ranging from 8.10 to 11.82 wt.%NaCl_(equiv).Oxygen isotope data(δ^(18)O_(H2O)O)range from+4.8‰to+8.1‰,suggesting a magmatic origin for the ore-forming fluids,later diluted by meteoric water.Sulfur isotope values(δ^(34)S_(H2S))between−6.0‰and−9.1‰confirm a magmatic source.Fluid mixing and dilution are identified as the primary mechanisms for ore precipitation.Raman spectroscopy enables nondestructive identification of minerals through their unique vibrational peaks.Chalcopyrite(213,280,1304 cm^(−1)),hematite(214,282,469,689,1309 cm^(−1)),goethite(967 cm^(−1)),and quartz(125,198,458 cm^(−1))show distinct spectral fingerprints indicating mineral differentiation,alteration tracking,and structural analysis in geological studies.Based on its geological context,the Jalilabad Cu(±Au)deposit is interpreted as resembling a high-sulfidation epithermal deposit. 展开更多
关键词 Jalilabad Cu(±Au)deposit Zanjan Province GEOCHEMISTRY Fluid inclusion Stable isotope High-sulfidation epithermal deposit
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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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Study on the Characteristics of Atmospheric Dry and Wet Deposition in the Upper Reaches of Baiyangdian
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作者 Ye LI Hongbo LI +2 位作者 Qi ZHAO Ning LUO Xinyong CHEN 《Meteorological and Environmental Research》 CAS 2022年第1期63-66,共4页
To study the characteristics of atmospheric dry and wet deposition in the upper reaches of Baiyangdian,two sampling sites in Baoding City were monitored for 1 year from September 2018 to August 2019.The results showed... To study the characteristics of atmospheric dry and wet deposition in the upper reaches of Baiyangdian,two sampling sites in Baoding City were monitored for 1 year from September 2018 to August 2019.The results showed that the dry and wet deposition fluxes of total nitrogen(TN)during the monitoring period were 6.87 and 6.46 kg/(hm^(2)·a),respectively.The ratio of wet to dry deposition of TN was approximately 1∶1,with wet deposition being dominated by ammonium nitrogen deposition.The dry and wet deposition fluxes of total phosphorus(TP)were 0.228 and 0.125 kg/(hm^(2)·a),and it was dominated by dry deposition.The average concentration of TN in wet deposition exceeded the standard threshold for eutrophic waters,and its ecological effects on the Baiyangdian basin should be concerned.Wet deposition fluxes of nitrogen and phosphorus had a significantly positive correlation with rainfall,while their deposition concentrations were negatively correlated with rainfall.The dry deposition of atmospheric nitrogen and phosphorus was influenced by the amount of dustfall and climatic factors such as rainfall,temperature,and humidity,which mainly occurred from April to August. 展开更多
关键词 Atmospheric deposition Dry and wet deposition Nitrogen deposition Phosphorus deposition deposition flux
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Enhanced atmospheric phosphorus deposition in Asia and Europe in the past two decades 被引量:15
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作者 Yuepeng Pan Bowen Liu +3 位作者 Jing Cao Jin Liu Shili Tian Enzai Du 《Atmospheric and Oceanic Science Letters》 CSCD 2021年第5期8-12,共5页
There is increasing interest in understanding atmospheric phosphorus(P)deposition and its impacts on plant pro-ductivity and carbon sinks in ecosystems.However,the global pattern of P deposition remains poorly underst... There is increasing interest in understanding atmospheric phosphorus(P)deposition and its impacts on plant pro-ductivity and carbon sinks in ecosystems.However,the global pattern of P deposition remains poorly understood,primarily due to the sparseness of data in Asia.In this study,the authors compiled 396 published observations of atmospheric P deposition from 1959 to 2020 on the global scale.The results gave a geometric mean bulk P deposition value of 0.32 kg ha−1 yr−1,or a global P budget of 4.4 Tg yr−1.Compared with the period 1959-2000,the authors found an elevated P deposition in Europe and Asia during 2001-2020,likely due to the increas-ing agricultural emissions and fossil fuel combustion-related sources in addition to dust emissions.The findings highlight the need to quantify the impacts of elevated P deposition from anthropogenic emissions on long-term ecosystem development in the context of carbon neutrality and clean-air actions. 展开更多
关键词 Atmospheric phosphorus deposition Wet deposition Dry deposition Bulk deposition Air pollution
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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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Classification and mineralization of global lithium deposits and lithium extraction technologies for exogenetic lithium deposits 被引量:4
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作者 Mian-ping Zheng En-yuan Xing +5 位作者 Xue-fei Zhang Ming-ming Li Dong Che Ling-zhong Bu Jia-huan Han Chuan-yong Ye 《China Geology》 CAS CSCD 2023年第4期547-566,共20页
A reasonable classification of deposits holds great significance for identifying prospecting targets and deploying exploration. The world ’s keen demand for lithium resources has expedited the discovery of numerous n... A reasonable classification of deposits holds great significance for identifying prospecting targets and deploying exploration. The world ’s keen demand for lithium resources has expedited the discovery of numerous novel lithium resources. Given the presence of varied classification criteria for lithium resources presently, this study further ascertained and classified the lithium resources according to their occurrence modes, obtaining 10 types and 5 subtypes of lithium deposits(resources) based on endogenetic and exogenetic factors. As indicated by surveys of Cenozoic exogenetic lithium deposits in China and abroad,the formation and distribution of the deposits are primarily determined by plate collision zones, their primary material sources are linked to the anatectic magmas in the deep oceanic crust, and they were formed primarily during the Miocene and Late Paleogene. The researchers ascertained that these deposits,especially those of the salt lake, geothermal, and volcanic deposit types, are formed by unique slightly acidic magmas, tend to migrate and accumulate toward low-lying areas, and display supernormal enrichment. However, the material sources of lithium deposits(resources) of the Neopaleozoic clay subtype and the deep brine type are yet to be further identified. Given the various types and complex origins of lithium deposits(resources), which were formed due to the interactions of multiple spheres, it is recommended that the mineralization of exogenetic lithium deposits(resources) be investigated by integrating tectono-geochemistry, paleoatmospheric circulation, and salinology. So far, industrialized lithium extraction is primarily achieved in lithium deposits of the salt lake, clay, and hard rock types. The lithium extraction employs different processes, with lithium extraction from salt lake-type lithium deposits proving the most energy-saving and cost-effective. 展开更多
关键词 Exogenetic lithium deposit Endogenetic lithium deposit deposit type Salt lake type Deep brine type Geothermal type Volcanic deposit type Clay type Supernormal supergene enrichment SGSP lithium extraction techology Invention patent Mineral resource exploration engineering
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Classification,metallogenesis and exploration of silver deposits in Daxing’anling of Inner Mongolia and its adjacent areas 被引量:2
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作者 Biao Jiang Deng-hong Wang +12 位作者 Yu-chuan Chen Tong Zhang Xiu-lang Pu Wen-wen Ma Yan Wang Guang Wu Li-wen Wu Tong Zhang Xue-jiao Li Jie Yan Yu-shan Zuo Hong-jun Sun Zhi-yuan Li 《China Geology》 CAS 2022年第4期595-613,共19页
By the end of 2020,83 silver deposits(or ore occurrences),including four super-large-scale deposits,nine large-scale deposits,33 medium-scale deposits and 37 small-scale deposits or ore occurrences,have been proved.Th... By the end of 2020,83 silver deposits(or ore occurrences),including four super-large-scale deposits,nine large-scale deposits,33 medium-scale deposits and 37 small-scale deposits or ore occurrences,have been proved.The amount of silver metal exceeds 86000 t with average grade of 100 g/t,which makes Daxing’anling region one of the the most important silver ore belt in China.However,the metallogenic characteristics and metallogenesis need to be clarified.The silver deposits in the study area are classified into three main types,which are magmatic hydrothermal vein type,continental volcano-subvolcanic type and skarn type,respectively.The supergiant deposits include the Shuangjianzishan deposit(silver metal amount of 15214 t with average grade of 138 g/t),the Baiyinchagandongshan deposit(silver metal amount of 9446 t with average grade of 187 g/t),the Huaobaote deposit(silver metal amount of 6852 t with average grade of 170 g/t),and the Fuxingtun deposit(silver metal amount of 5240 t with average grade of 196 g/t).The silver deposits are mainly distributed in the central and south of the Daxing’anling area,and mainly formed in the Yanshanian period.The silver polymetallic deposits in the Daxinganling area are significantly controlled by regional faults and the junction zone of volcanic rock basins and their margins.The north-east trending deep faults are the most important ore-controlling structures in this area.The distribution of silver polymetallic deposits along the main faults is obvious,and the intersection area of multiple groups of faults often form important mine catchments.The Permian is the most important ore-bearing formation in this area,but some important silver polymetallic deposits occur in Mesozoic volcanic basins or pre-Mesozoic strata.The magmatic rocks related to mineralization are mainly intermediate acidic or acidic intrusions,intermediate acidic lavas,pyroclastic rocks,and small intrusions of ultra-shallow or shallow facies of the Yanshanian Period.The mineralization element combination is mainly determined by the elemental geochemical background of surrounding rocks or source layers.In addition,the type of deposit,the distance from the mineralization center,and the degree of differentiation of ore-forming rock mass are also important influence factors.The article analyzes the prospecting prospects of each silver deposit type in the study area,discusses the relationship between mineralization center and deep prospecting,and proposes that porphyry silver deposits should be paid attention to.In the prospecting and exploration of silver deposits,comprehensive evaluation and multi-target prospecting need to be strengthened because silver can coexist or be associated with a variety of metals. 展开更多
关键词 Silver deposit deposit type Porphyry silver deposit Supergiant silver deposit METALLOGENESIS Mineral exploration engineering Prospecting direction Daxing’anling Inner Mongolia
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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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Newly Identified Au-Ag-Bi-Te Mineralization in the Aydindere Skarn Fe and Cu Deposit,Giresun,NE Turkey:Implications of Gold Mineralization during Retrograde Skarn Evolution 被引量:1
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作者 Ahmet Sasmaz Vitaliy Sukach +7 位作者 Serhiy Bondarenko Hryhorii Aleksiienko Hengameh Erfanian Kaseb Bilge Sasmaz Sergiy Kurylo Oleksandr Hrinchenko Volodymyr Somka Panagiotis Voudouris 《Journal of Earth Science》 2025年第2期543-561,共19页
This study investigates the mineralogy and mineral-chemistry of a newly discovered Au-Ag-Bi-Te mineralization at the Aydindere Fe-Cu skarn deposit,within the Pontides Tectonic Unit,northeastern Turkey.The mineralizati... This study investigates the mineralogy and mineral-chemistry of a newly discovered Au-Ag-Bi-Te mineralization at the Aydindere Fe-Cu skarn deposit,within the Pontides Tectonic Unit,northeastern Turkey.The mineralization is developed in the skarn zone at the contact between Upper Cretaceous andesite-pyroclastic rocks and a Paleocene–Eocene I-type granitoid.The principal ore minerals of the Aydindere Fe-Cu deposit are oxides(magnetite),sulfides(pyrite-chalcopyritegalena-sphalerite),tellurides/sulfotellurides(tetradymite,hessite),sulfosalts(wittichenite,emplectite,aikinite) and native gold-electrum.Skarn minerals include anhydrous phases(garnet) formed in a prograde stage and hydrous phases(amphibole,epidote,chlorite),which were formed in a retrograde stage in association with quartz,adularia,apatite and late calcite.Sulfides,tellurides and sulfosalts are introduced during the retrograde stage.The Au-Ag-Bi-Te mineralization was detected for the first time within the western ore body of the Aydindere deposit,and occurs in calcite-bearing sulfide bodies that cut magnetite-garnet-amphibole-epidote skarns with magnetite ores of different grade,including massive magnetite.Chlorite geothermometry indicates formation of the Au-Ag-BiTe mineralization at temperatures between 300 and 250 ℃,during the retrograde skarn evolution.Assuming the temperature is ~275 ℃,logfS_(2) =-10.5 to-13,logfO_(2) =-37 to-33,and logf Te2 values range from approximately-12 to-8.5 were estimated.The available mineralogical and geological data(presences of magnetite,oxidized-type tellurides/sulfotellurides,and andraditic garnets,and absence of pyrrhotite and arsenopyrite) suggest that Aydindere is an oxidized Au-bearing skarn deposit.The discovery of Au-Ag-Bi-Te mineralization at Aydindere increases its productivity and requires more detailed exploration in the deposit for precious(Au,Ag) and critical(Bi,Te) metals. 展开更多
关键词 aydindere Black Sea Region telluredes oxidized gold-bearing skarn deposit mineral geology
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Laser-directed energy deposition of high-strength Ti6Al4V with equiaxed grain via multi-alloying CoCrMoSi 被引量:1
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作者 Li Zhao Chao-Lin Tan +3 位作者 Tong-Shuai Zhao Chang-Jun Qiu Xiao-Ming Wang Hong-Mei Zhu 《Rare Metals》 2025年第7期5061-5077,共17页
The wide application of additive-manufactured Ti alloys is impeded by coarse columnar grains along the building direction and thus the severe anisotropy of mechanical properties.To address this issue,a novel multiallo... The wide application of additive-manufactured Ti alloys is impeded by coarse columnar grains along the building direction and thus the severe anisotropy of mechanical properties.To address this issue,a novel multialloying CoCrMoSi strategy has been developed to produce near-equiaxed grains of a modified Ti6Al4V(TC4)alloy for laser-directed energy deposition(LDED)based on computational thermodynamic and experimental approaches.The results show that the microstructure of the TC4alloy consists of large columnar β grains and α/α'laths with a high aspect ratio of 5.73,exhibiting a strong anisotropy of tensile properties.In contrast,the TC4-1.5%CoCrMoSi alloy is characterized by mixed columnarequiaxed β grains and near-equiaxed β grains with increased CoCrMoSi additions to 4.5%.Additionally,the α/α'laths are successively refined with the increase of CoCrMoSi content,showing an aspect ratio of smaller than4.31.However,an excess addition of CoCrMoSi leads to the formation of micro voids.After multi-alloyingCoCrMoSi,the number density of twins increases remarkably with a substantially reduced width,because of the increased lattice distortion and dislocation density together with the reducedβ→αphase transformation temperature.The anisotropy of the tensile properties can be effectively eliminated by adding 3 wt%CoCrMoSi with an exemplary strength-ductility combination,superior to the LDEDed-modified TC4 alloy in the literature reporting the tensile properties along both horizontal(X)and vertical(Z)directions.The underlaying mechanisms for the evolution of the microstructure and the tensile properties induced by multi-alloying CoCrMoSi were discussed in detail. 展开更多
关键词 Laser-directed energy deposition Equiaxed titanium alloy MULTI-ALLOYING Microstructural evolution Strengthening mechanism
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