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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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Association between intra-pancreatic fat deposition and diseases of the exocrine pancreas: A narrative review
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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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Ore-forming mechanism of Huxu Au-dominated polymetallic deposit in the Dongxiang Basin,South China:Constraints from in-situ trace elements and S-Pb isotopes of pyrite
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作者 Hongze Gao Jiajie Chen +3 位作者 Chengbiao Leng Yuhui Hu Huidan Xie Zenghua Li 《Acta Geochimica》 EI CAS CSCD 2024年第6期1223-1240,共18页
The Huxu Au-dominated polymetallic deposit is a hydrothermal deposit located in the Dongxiang volcanic basin in the middle section of the Gan-Hang tectonic belt in South China.The orebodies primarily occur within the ... The Huxu Au-dominated polymetallic deposit is a hydrothermal deposit located in the Dongxiang volcanic basin in the middle section of the Gan-Hang tectonic belt in South China.The orebodies primarily occur within the Jurassic-Cretaceous quartz diorite porphyry,while the genesis of this deposit is unclear.This study focused on geological and mineralogical characteristics,in-situ trace elements and S-Pb isotopes of three generations of pyrite of the Huxu deposit to clarify the distribution of trace elements in pyrite,ore-forming fluid and material sources,and genetic types of the deposit.The mineralization stage of the deposit can be divided into quartz-pyrite stage(S1),quartz-pyrite-hematite stage(S2),quartz-polymetallic sulfide stage(S3)and quartz-hematite stage(S4),with the corresponding pyrite being divided into three generations(Py1-Py3).in-situ trace element data of pyrite show that Au in pyrite mainly exists in the form of solid solution(Au^(+)),and the content is relatively low at all stages(0.18 ppm for Py1,0.32 ppm for Py2,0.68 ppm for Py3),while Pb and Zn mainly exist as sulfide inclusions in the pyrite.S-Pb isotopes show that the sulfur and ore-forming material of this deposit are mainly sourced from magma.The mineral association,mineral textures and trace elements in different stages of pyrite indicate that fluid boiling and fluid mixing are the key factors of native gold precipitation in S2 and S4,respectively,while water-rock interaction controlled the precipitation of Pb-Zn sulfides.These integrating with geological characteristics suggests that the deposit should be an intermediate sulfidation epithermal deposit. 展开更多
关键词 Au-dominated Polymetallic deposit Intermediate sulfidation Epithermal deposit PYRITE Trace element S-Pb isotope Tectonic belt
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Geology and S-Pb isotope geochemistry of the Hatu gold deposit in West Junggar,NW China:Insights into ore genesis and metal source
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作者 Shen Han Zhenju Zhou +6 位作者 Xiaohua Deng Yanshuang Wu Xi Chen Abulimiti Aibai Yong Wang Xiaoyu Jia Yanjing Chen 《Acta Geochimica》 EI CAS CSCD 2024年第6期1205-1222,共18页
The Hatu gold deposit is the largest historical gold producer of the West Junggar,western China,with an Au reserve of about 62 t.The orebodies were controlled by NE-,EW-,and NW-trending subsidiary faults associated wi... The Hatu gold deposit is the largest historical gold producer of the West Junggar,western China,with an Au reserve of about 62 t.The orebodies were controlled by NE-,EW-,and NW-trending subsidiary faults associated with the Anqi fault.This deposit exhibits characteristics typical of a fault-controlled lode system,and the orebodies consist of auriferous quartz veins and altered wall rocks within Early Carboniferous volcano-sedimentary rocks.Three stages of mineralization have been identified in the Hatu gold deposit:the early pyrite-albite-quartz stage,the middle polymetallic sulfides-ankerite-quartz stage,and late quartz-calcite stage.The sulfur isotopic values of pyrite and arsenopyrite vary in a narrow range from-0.8‰to1.3‰and an average of 0.4‰,the near-zeroδ~(34)S values implicate the thorough homogenization of the sulfur isotopes during the metamorphic dehydration of the Early Carboniferous volcano-sedimentary rocks.Lead isotopic results of pyrite and arsenopyrite(^(206)Pb/^(204)Pb=17.889-18.447,^(207)Pb/^(204)Pb=15.492-15.571,^(208)Pb/^(204)Pb=37.802-38.113)are clustered between orogenic and mantle/upper crust lines,indicating that the lead was mainly sourced from the hostrocks within the Early Carboniferous Tailegula Formation.The characteristics of S and Pb isotopes suggest that the ore-forming metals of the Hatu orogenic gold deposit are of metamorphogenic origin,associated with the continental collision between the Yili-Kazakhstan and Siberian plates during the Late Carboniferous. 展开更多
关键词 Hatu gold deposit Sulfur isotope Lead isotope Orogenic gold deposit West Junggar
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Origin of the Yueguang gold deposit in Xinhua, Hunan Province, South China: insights from fl uid inclusion and hydrogen–oxygen stable isotope analysis
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作者 Hongxin Fan Qiang Wang +2 位作者 Yulong Yang Yao Tang Hao Zou 《Acta Geochimica》 EI CAS CSCD 2024年第2期235-254,共20页
The Yueguang gold deposit is located in Fengjia,Xinhua County,Hunan Province,South China.It represents a recently discovered small-scale gold deposit situated in the southwestern region of the Jiangnan Orogenic Belt,w... The Yueguang gold deposit is located in Fengjia,Xinhua County,Hunan Province,South China.It represents a recently discovered small-scale gold deposit situated in the southwestern region of the Jiangnan Orogenic Belt,west of the Baimashan granitic batholith.In order to discern the characteristics of the ore-formingfluids,the underlying mineralization processes,and establish a foundation for the origin of the Yueguang gold depositfluid inclusion micro-thermometry,as well as quartz hydrogen and oxygen isotope analysis,have been carried out on samples obtained from various stages of mineralization.The hydrothermal miner-alization stages within the Yueguang gold deposit can be categorized into three stages:(i)the barren,pre-ore quartz-pyrite stage(Stage Ⅰ),the quartz-pyrite-gold stage(Stage Ⅱ),and the post-ore quartz-carbonate stage(Stage Ⅲ),with the second stage being the main mineralization stage.Thefluid inclusions identified in samples from the main min-eralization stage can predominantly be described with the NaCl–H_(2)O and CO_(2)–NaCl–H_(2)O systems.These inclusions display homogenization temperatures ranging from 158.8 to 334.9℃,and thefluid salinity ranges from 0.3%to 4.0%(wt.%NaCl equiv.).Laser Raman spectroscopy analysis of individual inclusions further reveals the presence of gas-phases such as CO_(2),CH_(4),and N_(2).Isotopic analysis indicatesδ^(18)Ofluid values ranging from 3.95 to 6.7‰ and δDH_(2)O values ranging from-71.9 to-55.7‰.These results indi-cate that the ore-formingfluid of the Yueguang gold deposit belongs to metamorphic hydrothermalfluids of middle-low temperature and low salinity.In the process of ore formation,gold is transported in the form of Au(HS)2-complexes,with gold deposition being driven byfluid immiscibility.Therefore,the Yueguang gold deposit is categorized as an orogenic gold deposit dominated by metamorphic hydrother-malfluid.It may become a new target for gold exploration in the Baimashan region,central Hunan Province. 展开更多
关键词 Hunan province Yueguang gold deposit Fluid inclusions Hydrogen–oxygen isotopes Laser Raman Fluid immiscibility Orogenic gold deposit
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Depositional process of hyperpycnal flow deposits:A case study on Lower Cretaceous Sangyuan outcrop in the Luanping Basin,Northeast China
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作者 De-zhi Yan Ru-kai Zhu +8 位作者 Hao Shou Zhao-hui Xu Wei-hong Liu Si-cheng Zhu Zhi-cheng Lei Jing-ya Zhang Chang Liu Yi Cai Huai-min Xu 《China Geology》 CAS CSCD 2024年第3期505-516,共12页
Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this... Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this paper studies the depositional process of the hyperpycnal flow deposits,and divides their depositional process into three phases,namely,acceleration,erosion and deceleration.In the acceleration phase,hyperpycnal flow begins to enter the basin nearby,and then speeds up gradually.Deposits developed in the acceleration phase are reverse.In addition,the original deposits become unstable and are taken away by hyperpycnal flows under the eroding force.As a result,there are a lot of mixture of red mud pebbles outside the basin and gray mud pebbles within the basin.In the erosion phase,the reverse deposits are eroded and become thinner or even disappear.Therefore,no reverse grading characteristic is found in the proximal major channel that is closer to the source,but it is still preserved in the middle branch channel that is far from the source.After entering the deceleration phase,normally grading deposits appear and cover previous deposits.The final deposits in the basin are special.Some are reverse,and others are normal.They are superimposed with each other under the action of hyperpycnal flow.The analysis of the Sangyuan outcrop demonstrates the sedimentary process and distribution of hyperpycnites,and reasonably explain the sedimentary characteristics of hyperpycnites.It is helpful to the prediction of oil and gas exploration targets in gravity flow deposits. 展开更多
关键词 Hyperpycnal flow Sedimentary characteristics depositional process Gravity flow deposit Hyperpycnite Red mud pebble Gray mud pebble Oil and gas exploration engineering Luanping Basin
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Geology and mineralization of the Dongping supergiant alkalic-hosted Au-Te deposit(>100 t Au)in Northern Hebei Province,China:A review
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作者 Shi-min Zhen Da-zhao Wang +2 位作者 Zhong-jian Zha Hai-jun Bai Jiang Wang 《China Geology》 CAS CSCD 2024年第3期533-550,共18页
The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of Au.This paper presents a new understanding for Dongping ore system,based on the previous studies.The mineralization origi... The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of Au.This paper presents a new understanding for Dongping ore system,based on the previous studies.The mineralization originally occurred at 400-380 Ma,simultaneous with emplacement of the Shuiquangou alkaline complex,and was overprinted by the hydrothermal activity in the Yanshanian.Isotope compositions of ores indicate metals of the deposit are mainly provided by the Shuiquangou complex.Ore-forming fluids are characterized by increasing oxygen fugacity and decreasing sulfur fugacity,while tellurium fugacity increased in the Stage II-2 and decreased in Stage II-3.These systematic changes are closely related to the processes of mineral precipitation and fluid evolution.Sulfide precipitation from Stage Ⅰ to Stage Ⅱ was triggered by fluid boiling,which leads to the precipitation of Pb-Bi-Te,due to decrement of sulfur fugacity.Condensation of gas phase containing high concentration of H_2Te leads to precipitation of Te-Au-Ag minerals and native tellurium.Based on these hypotheses,this paper present a polyphase metallogenic model as follow.During the Devonian,fluids were released from alkaline magmas,which carried ore-forming materials form the surrounding rocks and precipitate the early ores.During the Jurassic-Cretaceous,fluorine-rich fluids exsolved from highly factionated Shangshuiquan granite,which extracted and concentrated Au from the Shuiquangou complex and the Sanggan Group metamorphic rocks,and finally formed the Dongping gold deposit. 展开更多
关键词 Mineralization and alteration Alkaline intrusion Au deposit Physicochemical conditions Metallogenic model Oxygen fugacity Sulfur fugacity Mechanisms of mineral precipitation Fluid boiling Fluorine-enriched fluid Dongping gold deposit North China Craton Mineral exploration engineering
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Geographical Distribution of Atmospheric Nitrogen Deposition in China and Its Response to Emission Control Policy
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作者 WEN Zhang YU Ziyin +7 位作者 SI Ruotong XU Wen WANG Kai LIU Lei TANG Aohan ZHANG Fusuo KEITH Goulding LIU Xuejun 《Chinese Geographical Science》 SCIE CSCD 2024年第6期1017-1031,共15页
Atmospheric nitrogen(N)deposition has experienced significant change because of anthropogenic emissions,thereby exerting a pronounced impact on global ecosystem services.With the rapid development of industry and agri... Atmospheric nitrogen(N)deposition has experienced significant change because of anthropogenic emissions,thereby exerting a pronounced impact on global ecosystem services.With the rapid development of industry and agriculture and the swift expansion of urban areas in China since the 1980s,reactive nitrogen(Nr)emissions and N deposition have substantially increased.In pursuit of im-proving air quality,China has implemented a series of environmental protection policies and undertaken diverse measures to reduce pol-lutant emissions.This paper is a review of multivariate data sources of atmospheric N deposition based on the results of literature from 1980 to 2023,and the original data from 1980 to 2020 are summarized,counted and calculated.The main findings are as follows:1)the annual average atmospheric N deposition ranged from approximately 20-40 kg/(ha·yr),with the variability primarily linked to different assessment methods;2)regional disparities were evident in the spatial distribution of N deposition,with elevated values concentrated in areas with intense Nr emissions;3)atmospheric N deposition significantly declined after 2010,particularly the deposition of oxidized N,while reduced N deposition remained stable.These results reflect the effects of China's serious control policies on nitrogen oxide(NO.)emissions and strengthen the importance of agricultural NH3 emission mitigation.This study contributes to a comprehensive understanding of the N dynamics in the emission-deposition process,and provides a scientific foundation for the research of environmental protection,climate change,and sustainable development. 展开更多
关键词 nitrogen deposition emission-deposition relationship reactive nitrogen hotspots emission control policy China
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Efficient stabilizing agent-free synthesis of gold nanoparticles via square-wave pulse deposition for enhanced catalytic performance in ethanol electrooxidation
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作者 Setia Budi Aulia Siti Pathoni +5 位作者 Annisa Auliya Suci Winarsih Mohammad Hamzah Fauzi Yusmaniar Babay Asih Suliasih Hilman Syafei 《Materials Reports(Energy)》 EI 2024年第4期67-74,I0002,共9页
The pressing environmental concerns and the depletion of fossil fuel reserves necessitate a transition toward sustainable energy sources.Ethanol,a renewable biomass-derived fuel,is a promising alternative due to its a... The pressing environmental concerns and the depletion of fossil fuel reserves necessitate a transition toward sustainable energy sources.Ethanol,a renewable biomass-derived fuel,is a promising alternative due to its availability and high energy density.This study investigates the synthesis of gold nanoparticles(Au NPs)via a square-wave pulse deposition technique,aiming to enhance catalytic activity for ethanol electrooxidation.By varying pulse durations,we were able to exert precise control over Au NP size and distribution without stabilizing agents.Characterization using field emission scanning electron microscopy and X-ray diffraction techniques confirmed the formation of clustered nanoparticles of metallic gold phase.Electrochemical characteristics analyses revealed that Au NPs synthesized with a 900 ms pulse duration exhibited the lowest charge transfer resistance and the highest electrochemically active surface area.The electrocatalytic performance test of these Au NPs demonstrated an anodic current density of 2.5 mA cm^-(2)and a Tafel slope of 78 mV dec^(-1),indicating superior catalytic performance and reaction kinetics.Additionally,the Au NPs showed high resistance to poisoning,as evidenced by a low j_(b)/j_(f)ratio of 0.28 and stable chronoamperometric response.These findings underscore the potential of this synthesis method for producing high-performance electrocatalysts utilized in exploiting ethanol's potential as an environmentally friendly energy carrier. 展开更多
关键词 Gold nanoparticles Stabilizing agent-free synthesis method Square-wave pulse deposition ELECTROdepositION Ethanol electrooxidation
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Influence of Scanning Patterns on Mechanical Behavior and Distortion in Laser Directed Energy Deposition
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作者 Qi Wang Bingjie Xiao Shaopeng Zheng 《Journal of Applied Mathematics and Physics》 2024年第11期3842-3859,共18页
Laser Directed Energy Deposition (LDED) marks a critical advance in intelligent manufacturing, enabling efficient near-net shape production of metal parts. This method is especially beneficial for aerospace and defens... Laser Directed Energy Deposition (LDED) marks a critical advance in intelligent manufacturing, enabling efficient near-net shape production of metal parts. This method is especially beneficial for aerospace and defense applications that require high precision. However, issues such as deformation and heat accumulation during production still affect the quality of the final products, necessitating further optimization of process parameters. This paper studies the effects of three deposition strategies on 316L stainless steel parts using LDED. The three strategies based on unidirectional scanning (US), zigzag scanning (ZS), and square spiral scanning (SS) are investigated by solid samples and samples with a central hole. The surface smoothness, defects, and mechanical properties of 316L samples manufactured with the above strategies are discussed by means of surface topography tests and metallographic characterization. Experimental results indicate that the zigzag scanning strategy yielded better results for solid components, and the square spiral scanning strategy is suitable for samples with a central hole. 展开更多
关键词 Directed Energy deposition deposition Strategy 316L Stainless Steel MICROSTRUCTURE MICROHARDNESS Surface Smoothness
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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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Jet formation and penetration performance of a double-layer charge liner with chemically-deposited tungsten as the inner liner 被引量:2
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作者 Bihui Hong Wenbin Li +2 位作者 Yiming Li Zhiwei Guo Binyou Yan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期374-385,共12页
This paper proposes a type of double-layer charge liner fabricated using chemical vapor deposition(CVD)that has tungsten as its inner liner.The feasibility of this design was evaluated through penetration tests.Double... This paper proposes a type of double-layer charge liner fabricated using chemical vapor deposition(CVD)that has tungsten as its inner liner.The feasibility of this design was evaluated through penetration tests.Double-layer charge liners were fabricated by using CVD to deposit tungsten layers on the inner surfaces of pure T2 copper liners.The microstructures of the tungsten layers were analyzed using a scanning electron microscope(SEM).The feasibility analysis was carried out by pulsed X-rays,slug-retrieval test and static penetration tests.The shaped charge jet forming and penetration law of inner tungsten-coated double-layer liner were studied by numerical simulation method.The results showed that the double-layer liners could form well-shaped jets.The errors between the X-ray test results and the numerical results were within 11.07%.A slug-retrieval test was found that the retrieved slug was similar to a numerically simulated slug.Compared with the traditional pure copper shaped charge jet,the penetration depth of the double-layer shaped charge liner increased by 11.4% and>10.8% respectively.In summary,the test results are good,and the numerical simulation is in good agreement with the test,which verified the feasibility of using the CVD method to fabricate double-layer charge liners with a high-density and high-strength refractory metal as the inner liner. 展开更多
关键词 Shaped charge Chemical vapor deposition TUNGSTEN Double-layer charge liner X-ray PENETRATION
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Review on laser directed energy deposited aluminum alloys 被引量:2
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作者 Tian-Shu Liu Peng Chen +7 位作者 Feng Qiu Hong-Yu Yang Nicholas Tan Yew Jin Youxiang Chew Di Wang Ruidi Li Qi-Chuan Jiang Chaolin Tan 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期84-131,共48页
Lightweight aluminum(Al)alloys have been widely used in frontier fields like aerospace and automotive industries,which attracts great interest in additive manufacturing(AM)to process high-value Al parts.As a mainstrea... Lightweight aluminum(Al)alloys have been widely used in frontier fields like aerospace and automotive industries,which attracts great interest in additive manufacturing(AM)to process high-value Al parts.As a mainstream AM technique,laser-directed energy deposition(LDED)shows good scalability to meet the requirements for large-format component manufacturing and repair.However,LDED Al alloys are highly challenging due to their inherent poor printability(e.g.low laser absorption,high oxidation sensitivity and cracking tendency).To further promote the development of LDED high-performance Al alloys,this review offers a deep understanding of the challenges and strategies to improve printability in LDED Al alloys.The porosity,cracking,distortion,inclusions,element evaporation and resultant inferior mechanical properties(worse than laser powder bed fusion)are the key challenges in LDED Al alloys.Processing parameter optimizations,in-situ alloy design,reinforcing particle addition and field assistance are the efficient approaches to improving the printability and performance of LDED Al alloys.The underlying correlations between processes,alloy innovation,characteristic microstructures,and achievable performances in LDED Al alloys are discussed.The benchmark mechanical properties and primary strengthening mechanism of LDED Al alloys are summarized.This review aims to provide a critical and in-depth evaluation of current progress in LDED Al alloys.Future opportunities and perspectives in LDED high-performance Al alloys are also outlined. 展开更多
关键词 additive manufacturing laser directed energy deposition(LDED) aluminum alloys PRINTABILITY aluminum matrix composite auxiliary fields mechanical properties
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Printability disparities in heterogeneous material combinations via laser directed energy deposition:a comparative study 被引量:1
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作者 Jinsheng Ning Lida Zhu +9 位作者 Shuhao Wang Zhichao Yang Peihua Xu Pengsheng Xue Hao Lu Miao Yu Yunhang Zhao Jiachen Li Susmita Bose Amit Bandyopadhyay 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期389-405,共17页
Additive manufacturing provides achievability for the fabrication of bimetallic and multi-material structures;however,the material compatibility and bondability directly affect the parts’formability and final quality... Additive manufacturing provides achievability for the fabrication of bimetallic and multi-material structures;however,the material compatibility and bondability directly affect the parts’formability and final quality.It is essential to understand the underlying printability of different material combinations based on an adapted process.Here,the printability disparities of two common and attractive material combinations(nickel-and iron-based alloys)are evaluated at the macro and micro levels via laser directed energy deposition(DED).The deposition processes were captured using in situ high-speed imaging,and the dissimilarities in melt pool features and track morphology were quantitatively investigated within specific process windows.Moreover,the microstructure diversity of the tracks and blocks processed with varied material pairs was comparatively elaborated and,complemented with the informative multi-physics modeling,the presented non-uniformity in mechanical properties(microhardness)among the heterogeneous material pairs was rationalized.The differences in melt flow induced by the unlike thermophysical properties of the material pairs and the resulting element intermixing and localized re-alloying during solidification dominate the presented dissimilarity in printability among the material combinations.This work provides an in-depth understanding of the phenomenological differences in the deposition of dissimilar materials and aims to guide more reliable DED forming of bimetallic parts. 展开更多
关键词 directed energy deposition PRINTABILITY microstructure MICROHARDNESS bimetallic parts
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Enhanced atmospheric phosphorus deposition in Asia and Europe in the past two decades 被引量:11
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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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ZmbZIP27 regulates nitrogen-mediated leaf angle by modulating lignin deposition in maize 被引量:1
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作者 Huan Chen Xiaoping Gong +3 位作者 Yu Guo Jingjuan Yu Wen-Xue Li Qingguo Du 《The Crop Journal》 SCIE CSCD 2024年第5期1404-1413,共10页
In grain crops such as maize(Zea mays),leaf angle(LA)is a key agronomic trait affecting light interception and thus planting density and yield.Nitrogen(N)affects LA in plants,but we lack a good understanding of how N ... In grain crops such as maize(Zea mays),leaf angle(LA)is a key agronomic trait affecting light interception and thus planting density and yield.Nitrogen(N)affects LA in plants,but we lack a good understanding of how N regulates LA.Here,we report that N deficiency enhanced lignin deposition in the ligular region of maize seedlings.In situ hybridization showed that the bZIP transcription factor gene ZmbZIP27 is mainly expressed in the phloem of maize vascular bundles.Under N-sufficient conditions,transgenic maize overexpressing ZmbZIP27 showed significantly smaller LA compared with wild type(WT).By contrast,zmbzip27_(ems)mutant showed larger LA under both N-deficient and N-sufficient conditions compared with WT.Overexpression of ZmbZIP27 enhanced lignin deposition in the ligular region of maize in the field.We further demonstrated that ZmbZIP27 could directly bind the promoters of the microRNA genes ZmMIR528a and ZmMIR528b and negatively regulate the expression levels of ZmmiR528.ZmmiR528 knockdown transgenic maize displayed erect architecture in the field by increasing lignin content in the ligular region of maize.Taken together,these results indicate that ZmbZIP27 regulates N-mediated LA size by regulating the expression of ZmmiR528 and modulating lignin deposition in maize. 展开更多
关键词 MAIZE NITROGEN Leaf angle Ligular region Lignin deposition
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Three-dimensional Modeling of Ore-forming Elements and Mineralization Prognosis for the Yechangping Mo Deposit,Henan Province,China 被引量:1
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作者 DING Gaoming JI Genyuan +5 位作者 YAN Guolong XU Yongzhong WANG Kunming XIAO Chun WANG Quanle GUO Dongbao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期736-752,共17页
Three-dimensional geochemical modeling of ore-forming elements is crucial for predicting deep mineralization.This approach provides key information for the quantitative prediction of deep mineral localization,three-di... Three-dimensional geochemical modeling of ore-forming elements is crucial for predicting deep mineralization.This approach provides key information for the quantitative prediction of deep mineral localization,three-dimensional fine interpolation,analysis of spatial distribution patterns,and extraction of quantitative mineral-seeking markers.The Yechangping molybdenum(Mo)deposit is a significant and extensive porphyry-skarn deposit in the East Qinling-Dabie Mo polymetallic metallogenic belt at the southern margin of the North China Block.Abundant borehole data on oreforming elements underpin deep geochemical predictions.The methodology includes the following steps:(1)Threedimensional geological modeling of the deposit was established.(2)Correlation,cluster,and factor analyses post delineation of mineralization stages and determination of mineral generation sequence to identify(Cu,Pb,Zn,Ag)and(Mo,W,mfe)assemblages.(3)A three-dimensional geochemical block model was constructed for Mo,W,mfe,Cu,Zn,Pb,and Ag using the ordinary kriging method,and the variational function was developed.(4)Spatial distribution and enrichment characteristics analysis of ore-forming elements are performed to extract geological information,employing the variogram and w(Cu+Pb+Zn+Ag)/w(Mo+W)as predictive indicators.(5)Identifying the western,northwestern,and southwestern areas of the mine with limited mineralization potential,contrasted by the northeastern and southeastern areas favorable for mineral exploration. 展开更多
关键词 3D geochemical model ore-forming elements GEOSTATISTICS deep mineralization prediction Yechangping Mo deposit
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Construction of Dynamic Alloy Interfaces for Uniform Li Deposition in Li-Metal Batteries 被引量:1
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作者 Qingwen Li Yulu Liu +7 位作者 Ziheng Zhang Jinjie Chen Zelong Yang Qibo Deng Alexander V.Mumyatov Pavel A.Troshin Guang He Ning Hu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期64-71,共8页
It is well accepted that a lithiophilic interface can effectively regulate Li deposition behaviors,but the influence of the lithiophilic interface is gradually diminished upon continuous Li deposition that completely ... It is well accepted that a lithiophilic interface can effectively regulate Li deposition behaviors,but the influence of the lithiophilic interface is gradually diminished upon continuous Li deposition that completely isolates Li from the lithiophilic metals.Herein,we perform in-depth studies on the creation of dynamic alloy interfaces upon Li deposition,arising from the exceptionally high diffusion coefficient of Hg in the amalgam solid solution.As a comparison,other metals such as Au,Ag,and Zn have typical diffusion coefficients of 10-20 orders of magnitude lower than that of Hg in the similar solid solution phases.This difference induces compact Li deposition pattern with an amalgam substrate even with a high areal capacity of 55 mAh cm^(-2).This finding provides new insight into the rational design of Li anode substrate for the stable cycling of Li metal batteries. 展开更多
关键词 diffusion coefficient dynamic alloy interfaces Li dendrites Li solid solution uniform Li deposition
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Thin polymer electrolyte with MXene functional layer for uniform Li^(+) deposition in all-solid-state lithium battery 被引量:1
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作者 Weijie Kou Yafang Zhang +3 位作者 Wenjia Wu Zibiao Guo Quanxian Hua Jingtao Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期71-80,共10页
Solid polymer electrolyte(SPE) shows great potential for all-solid-state batteries because of the inherent safety and flexibility;however, the unfavourable Li+deposition and large thickness hamper its development and ... Solid polymer electrolyte(SPE) shows great potential for all-solid-state batteries because of the inherent safety and flexibility;however, the unfavourable Li+deposition and large thickness hamper its development and application. Herein, a laminar MXene functional layer-thin SPE layer-cathode integration(MXene-PEO-LFP) is designed and fabricated. The MXene functional layer formed by stacking rigid MXene nanosheets imparts higher compressive strength relative to PEO electrolyte layer. And the abundant negatively-charged groups on MXene functional layer effectively repel anions and attract cations to adjust the charge distribution behavior at electrolyte–anode interface. Furthermore,the functional layer with rich lithiophilic groups and outstanding electronic conductivity results in low Li nucleation overpotential and nucleation energy barrier. In consequence, the cell assembled with MXene-PEO-LFP, where the PEO electrolyte layer is only 12 μm, much thinner than most solid electrolytes, exhibits uniform, dendrite-free Li+deposition and excellent cycling stability. High capacity(142.8 mAh g-1), stable operation of 140 cycles(capacity decay per cycle, 0.065%), and low polarization potential(0.5 C) are obtained in this Li|MXene-PEO-LFP cell,which is superior to most PEO-based electrolytes under identical condition. This integrated design may provide a strategy for the large-scale application of thin polymer electrolytes in all-solid-state battery. 展开更多
关键词 MXene nanosheet Laminar functional layer Thin polymer electrolyte Dendrite-free Liþdeposition All-solid-state lithium battery
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Tumor deposits in axillary adipose tissue in patients with breast cancer:Do they matter? 被引量:1
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作者 Muhammed Mubarak Rahma Rashid Shaheera Shakeel 《World Journal of Clinical Cases》 SCIE 2024年第6期1045-1049,共5页
Tumor deposits(TDs)are defined as discrete,irregular clusters of tumor cells lying in the soft tissue adjacent to but separate from the primary tumor,and are usually found in the lymphatic drainage area of the primary... Tumor deposits(TDs)are defined as discrete,irregular clusters of tumor cells lying in the soft tissue adjacent to but separate from the primary tumor,and are usually found in the lymphatic drainage area of the primary tumor.By definition,no residual lymph node structure should be identified in these tumor masses.At present,TDs are mainly reported in colorectal cancer,with a few reports in gastric cancer.There are very few reports on breast cancer(BC).For TDs,current dominant theories suggest that these are the result of lymph node metastasis of the tumor with complete destruction of the lymph nodes by the tumor tissue.Even some pathologists classify a TD as two lymph node metastases for calculation.Some pathologists also believe that TDs belong to the category of disseminated metastasis.Therefore,regardless of the origin,TDs are an indicator of poor prognosis.Moreover,for BC,sentinel lymph node biopsy is generally used at present.Whether radical axillary lymph node dissection should be adopted for BC with TDs in axillary lymph nodes is still inconclusive.The present commentary of this clinical issue has certain guiding significance.It is aimed to increase the awareness of the scientific community towards this under-recognized problem in BC pathology. 展开更多
关键词 Breast cancer Tumor deposits Lymph node metastasis STAGING
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