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High-Precision and Ultraspeed Monitoring of Melt-Pool Morphology in Laser-Directed Energy Deposition Using Deep Learning 被引量:2
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作者 Jiayu Yang Guan Liu +4 位作者 Wei Zhu Yingjie Zhang Wenbin Zhou Defu Liu Yongcheng Lin 《Additive Manufacturing Frontiers》 2025年第2期81-89,共9页
Laser-directed energy deposition(L-DED)is an advanced additive manufacturing technology primarily adopted in metal three-dimensional printing systems.The L-DED process is characterized by various defects,thus necessit... Laser-directed energy deposition(L-DED)is an advanced additive manufacturing technology primarily adopted in metal three-dimensional printing systems.The L-DED process is characterized by various defects,thus necessitating the extensive use of in-situ monitoring to enable real-time adjustments of process parameters by detecting molten-pool features.To address the challenge of accurately extracting the molten-pool morphology from an undetached spatter,an innovative monitoring method based on the U-Net(U-shaped network)is proposed herein.A lightweight architecture accelerates the processing speed,whereas an enhanced loss function incorporating weight maps augments the segmentation precision.The model performance is evaluated by comparing its segmentation accuracy and processing speed with those of the conventional U-Net,using the mean intersection over union(MIoU)as the segmentation metric.The improved model demonstrates superior segmentation accuracy at the interface between the molten pool and spatter,with a peak MIoU of 0.9798 achieved on the test set.Furthermore,this model processes each image in an extremely short time of 17.9 ms.Using this segmentation algorithm,the error in extracting the molten-pool width from single-track experiments is within 0.1 mm.The proposed method for monitoring the molten-pool morphology is suitable for deployment in online monitoring systems,thus providing a foundation for subsequent process-parameter regulation. 展开更多
关键词 Laser-directed energy deposition Molten-pool morphology Semantic segmentation Mean intersection over union(MIoU)
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Multicomponent Gd_(1−x)Sm_(x)Ba_(0.5)Sr_(0.5)CoCuO_(5+δ) double perovskites as oxygen electrodes for solid oxide cells:Effect of chemical composition and electrospun morphology 被引量:1
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作者 Jacek Winiarski Piotr Winiarz Konrad Świerczek 《International Journal of Minerals,Metallurgy and Materials》 2025年第11期2628-2638,共11页
Multicomponent Gd_(1−x)Sm_(x)Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)double perovskites are optimized for application in terms of chemical composi-tion and morphology for the use as oxygen electrodes in solid oxide cells.Structur... Multicomponent Gd_(1−x)Sm_(x)Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)double perovskites are optimized for application in terms of chemical composi-tion and morphology for the use as oxygen electrodes in solid oxide cells.Structural studies of other physicochemical properties are con-ducted on a series of materials obtained by the sol-gel method with different ratios of Gd and Sm cations.It is documented that changing the x value,and the resulting adjustment of the average ionic radius,have a significant impact on the crystal structure,stability,as well as on the total conductivity and thermomechanical properties of the materials,with the best results obtained for the Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)composition.Oxygen electrodes are prepared using the selected compound,allowing to obtain low polarization resistance values,such as 0.086Ω·cm^(2)at 800℃.Systematic studies of electrocatalytic activity are conducted using La_(0.8)Sr_(0.2)Ga_(0.8)Mg_(_(0.2))O_(3−δ)as the electrolyte for all electrodes,and Ce_(0.8)Gd_(0.2)O_(2−δ)electrolyte for the best performing Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)electrodes.The electrochemical data are analyzed using the distribution of relaxation times method.Also,the influence of the preparation method of the electrode material is in-ve`stigated using the electrospinning technique.Finally,the performance of the Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)electrodes is tested in a Ni-YSZ(yttria-stabilized zirconia)anode-supported cell with a Ce_(0.8)Gd_(0.2)O_(2−δ)buffer layer,in the fuel cell and electrolyzer operating modes.With the electrospun electrode,a power density of 462 mW·cm^(−2)is obtained at 700℃,with a current density of ca.0.2 A·cm^(−2)at 1.3 V for the electrolysis at the same temperature,indicating better performance compared to the sol-gel-based electrode. 展开更多
关键词 multicomponent oxides double perovskites morphology modification ELECTROSPINNING oxygen electrodes solid oxide cells
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Morphology and vegetation dynamics in a macro-tidal tropical estuary with high fluvial discharge:A case study of the Salween River Delta 被引量:1
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作者 HE Aoyang HUANG Jiangcheng SUN Zhengbao 《Journal of Geographical Sciences》 2025年第3期577-597,共21页
A macro-tidal tropical estuary with high fluvial discharge is characterized by both fragility and remarkable dynamism.This study utilizes the Salween River Delta(SRD)as a case example to examine the interplay between ... A macro-tidal tropical estuary with high fluvial discharge is characterized by both fragility and remarkable dynamism.This study utilizes the Salween River Delta(SRD)as a case example to examine the interplay between morphology and vegetation under similar tidal conditions.Our analysis of correlations and inferences revealed several significant trends in the SRD:(1)an overall expansion of land area and intertidal vegetation,with the most pronounced changes occurring in the eastern sector;(2)the predominance of river discharge influencing the southwestern and northern sectors,contrasted with the primary impact of storm surges in the eastern sector;and(3)three distinct causal relationships among estuarine morphology,vegetation,storm surges,and river discharge:a direct model where river discharge shapes estuarine morphology,a progressive model in which river discharge affects vegetation distribution,subsequently influencing estuarine morphology,and a hybrid model where storm surges directly impact vegetation and indirectly modify its distribution through changes in estuarine morphology.The stability of sediment supply and the role of intertidal vegetation are crucial for the continuous seaward advance,providing a vital foundation for the protection and development of estuarine deltas. 展开更多
关键词 high fluvial discharge macro-tidal estuary deltaic morphology intertidal vegetation Salween River Delta
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Optimizing electrical output performance of triboelectric nanogenerators by micro-/nano-morphology design and fabrication 被引量:1
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作者 Jiaxin Han Xingyi Dai +1 位作者 Long-Biao Huang Jianhua Hao 《International Journal of Extreme Manufacturing》 2025年第3期260-288,共29页
Fueled by the increasing imperative for sustainable energy solutions and the burgeoning emphasis on health awareness,self-powered techniques have undergone notable strides in advancement.Triboelectric nanogenerators(T... Fueled by the increasing imperative for sustainable energy solutions and the burgeoning emphasis on health awareness,self-powered techniques have undergone notable strides in advancement.Triboelectric nanogenerators(TENGs)stand out as a prominent device capitalizing on the principles of triboelectrification and electrostatic induction to generate electricity or electrical signals.In efforts to augment the electrical output performance of TENGs and broaden their range of applications,researchers have endeavored to refine materials,surface morphology,and structural design.Among them,physical morphological modifications play a pivotal role in enhancing the electrical properties of TENGs by increasing the contact surface area,which can be achieved by building micro-/nano-structures on the surface or inside the friction material.In this review,we summarize the common morphologies of TENGs,categorize the morphologies into surface and internal structures,and elucidate their roles in enhancing the electric output performance of devices.Moreover,we systematically classify the methodologies employed for morphological preparation into physical and chemical approaches,thereby furnishing a comprehensive survey of the diverse techniques.Subsequently,typical applications of TENGs with special morphology divided by energy harvesting and self-powered sensors are presented.Finally,an overview of the challenges and future trajectories pertinent to TENGs is conducted.Through this endeavor,the aim of this article is to catalyze the evolution of further strategies for enhancing performance of TENGs. 展开更多
关键词 triboelectric nanogenerator morphology modification micro-/nano-structures physical and chemical fabrication electrical output performance
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The interaction between KIF21A and KANK1 regulates dendritic morphology and synapse plasticity in neurons
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作者 Shi-Yan Sun Lingyun Nie +5 位作者 Jing Zhang Xue Fang Hongmei Luo Chuanhai Fu Zhiyi Wei Ai-Hui Tang 《Neural Regeneration Research》 SCIE CAS 2025年第1期209-223,共15页
Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and memory.Kinesin-4 KIF21A helps organize the microtubule-actin network at th... Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and memory.Kinesin-4 KIF21A helps organize the microtubule-actin network at the cell cortex by interacting with KANK1;however,whether KIF21A modulates dendritic structure and function in neurons remains unknown.In this study,we found that KIF21A was distributed in a subset of dendritic spines,and that these KIF21A-positive spines were larger and more structurally plastic than KIF21A-negative spines.Furthermore,the interaction between KIF21A and KANK1 was found to be critical for dendritic spine morphogenesis and synaptic plasticity.Knockdown of either KIF21A or KANK1 inhibited dendritic spine morphogenesis and dendritic branching,and these deficits were fully rescued by coexpressing full-length KIF21A or KANK1,but not by proteins with mutations disrupting direct binding between KIF21A and KANK1 or binding between KANK1 and talin1.Knocking down KIF21A in the hippocampus of rats inhibited the amplitudes of long-term potentiation induced by high-frequency stimulation and negatively impacted the animals’cognitive abilities.Taken together,our findings demonstrate the function of KIF21A in modulating spine morphology and provide insight into its role in synaptic function. 展开更多
关键词 ACTIN CYTOSKELETON dendrite KANK1 KIF21A MICROTUBULE spine morphology SPINE synaptic plasticity talin1
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Morphology engineering of ZnO micro/nanostructures under mild conditions for optoelectronic application
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作者 Liang Chu Haoyu Shen +3 位作者 Hudie Wei Hongyu Chen Guoqiang Ma Wensheng Yan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期498-503,共6页
Zinc oxide(ZnO)serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 eV.Solvothermal reaction is commonly used in the synthesis of ZnO micro/nanostructures,given its low cost,si... Zinc oxide(ZnO)serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 eV.Solvothermal reaction is commonly used in the synthesis of ZnO micro/nanostructures,given its low cost,simplicity,and easy implementation.Moreover,ZnO morphology engineering has become desirable through the alteration of minor conditions in the reaction process,particularly at room temperature.In this work,ZnO micro/nanostructures were synthesized in a solution by varying the amounts of the ammonia added at low temperatures(including room temperature).The formation of Zn^(2+)complexes by ammonia in the precursor regulated the reaction rate of the morphology engineering of ZnO,which resulted in various structures,such as nanoparticles,nanosheets,microflowers,and single crystals.Finally,the obtained ZnO was used in the optoelectronic application of ultraviolet detectors. 展开更多
关键词 morphology engineering low temperature ZnO nanosheets microflowers ultraviolet detector
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Tuning support morphology to control alloy over PtCo/γ-Al_(2)O_(3) for the preferential oxidation of CO
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作者 SONG Lichuan ZHONG Liding +3 位作者 SHEN Jia LOU Yake GUO Yun WANG Li 《燃料化学学报(中英文)》 北大核心 2025年第1期96-105,共10页
The preferential oxidation of CO(CO-PROX)reaction is a cost-effective method for eliminating trace amounts of CO from the fuel H2.Pt-based catalysts have been extensively studied for COPROX,with their activity influen... The preferential oxidation of CO(CO-PROX)reaction is a cost-effective method for eliminating trace amounts of CO from the fuel H2.Pt-based catalysts have been extensively studied for COPROX,with their activity influenced by the morphology of the support.Hydrothermal synthesis was employed to produce different morphologies ofγ-Al_(2)O_(3):flower-likeγ-Al_(2)O_(3)(f)exposing(110)crystal faces,sheet-likeγ-Al_(2)O_(3)(s)revealing(100)crystal faces,and rod-likeγ-Al_(2)O_(3)(r)displaying(111)crystal faces,followed by loading PtCo nanoparticles.The exposed crystal faces of the support impact the alloying degree of the PtCo nanoparticles,and an increase in the alloying degree correlates with enhanced catalyst reactivity.Pt_(3)Co intermetallic compounds were identified onγ-Al_(2)O_(3)(f)exposing(110)crystal faces,and PtCo/γ-Al_(2)O_(3)(f)showed high catalytic activity in the CO-PROX reaction,achieving 100%CO conversion across a broad temperature range of 50−225°C.In contrast,only partial alloying of PtCo was observed onγ-Al_(2)O_(3)(s).Furthermore,no alloying between Pt and Co occurred in PtCo/γ-Al_(2)O_(3)(r),resulting in a reaction rate at 50°C that was merely 11%of that of PtCo/γ-Al_(2)O_(3)(f).The formation of Pt3Co intermetallic compounds led to a more oxidized state of Pt,which significantly diminished the adsorption of CO on Pt and augmented the active oxygen species,thereby facilitating the selective oxidation of CO. 展开更多
关键词 PtCo catalysts γ-Al_(2)O_(3) support morphology CO-PROX
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Volcanic Geomorphology and Morphometry Classification of Cinder Cone in Harrat Lunayyir Saudi Arabia by Using GIS and Remote Sensing
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作者 Azizah Aziz al Shehri 《Journal of Environmental & Earth Sciences》 2025年第5期304-318,共15页
Harrat Lunayyir,a volcanic field in western Saudi Arabia,exhibits diverse geomorphological and topographical features shaped by volcanic,tectonic,and climatic processes.This study integrates field observations,remote ... Harrat Lunayyir,a volcanic field in western Saudi Arabia,exhibits diverse geomorphological and topographical features shaped by volcanic,tectonic,and climatic processes.This study integrates field observations,remote sensing,and GIS analysis to investigate the spatial distribution and relationships between volcanic landforms,lava flows,and topographical variation result obtained is a morphological classification of the cinder cones of Harrat Lunayyir,which can be sub-divided into four types:tephra rings,horseshoe-shaped volcanoes,multiple volcanoes and volcanoes without craters.All of these are monogenetic volcanoes,unlike central volcanoes(stratovolcanoes)which live for tens or hundreds of thousands of years and erupt numerous times.In Harrat Lunayyir,there is a clear dominance of arched horseshoe-shaped volcanoes(58)over ring-shaped cinder cones(10),A1_symmetric cones(circular,uniform cinder cones with a single crater)(32),A2_asymmetric cones(elongated,irregular cones and may feature one or more craters)(8),volcanoes without craters(55)and multiple volcanoes(20).The classification presented in this paper makes it possible to include all morphological types of volcanoes found in the region.This fact also renders the present classification a useful tool to apply in other,both insular and continental volcanic areas to eventually analyze and systematize the study of eruptive edifices with similar traits.Hence,this research will explore the standard physical volcanology literature so as to follow accepted definitions. 展开更多
关键词 GIS morphology DEM Topography LITHOLOGY Cinder Cones
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Morphology,transcriptome,and proteome analysis of gill tissue in Acanthopagrus latus infected with Cryptocaryon irritans
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作者 Luxin Bai Man Jiang +3 位作者 Dongling Zhang Jing Zhang Liangmin Huang Xiande Liu 《Acta Oceanologica Sinica》 2025年第9期145-157,共13页
Cryptocaryon irritans is the parasite responsible for“white spot disease”in the yellowfin seabream Acanthopagrus latus,which has caused significant losses to the aquaculture industry.This experiment investigated the... Cryptocaryon irritans is the parasite responsible for“white spot disease”in the yellowfin seabream Acanthopagrus latus,which has caused significant losses to the aquaculture industry.This experiment investigated the changes in the morphology,transcriptome,and proteome of gill tissue in yellowfin seabream infected with C.irritans,aiming to provide foundational data for further understanding the pathogenic mechanisms and control measures against this parasite.The main findings were as follows,after C.irritans infection,the structure of gill tissue in yellowfin seabream was damaged,with microvessels ruptured,some cells proliferating,and large amounts of mucus infiltrating.Transcriptome analysis revealed a total of 4299 differentially expressed genes,with 2367 up-regulated and 1932down-regulated.Further bioinformatics analysis of all differentially expressed genes identified nine immune-related genes,cox-2,mcama,tbx21,dcn,tnfb,cd74a,illb,ppib,and cd4-1 in A.latus.The reliability of the transcriptome data was validated by real time q PCR,which showed the same trend as the RNA-seq results.Proteome analysis found365 differential proteins,with 180 proteins up-regulated and 185 proteins down-regulated.Bioinformatics analysis identified three immune-related proteins,Myll,Gapdh,and Actn3b.These findings indicated that C.irritans disrupted the structure of gill tissue,impeded gas exchange and led to asphyxiation and death in affected fish.Transcriptome and proteome analyses showed that the expression of immune-related genes and proteins in yellowfin seabream,involved not only inflammatory responses and the activation and migration of immune cells but also potentially participated in tissue repair and defense regulation.These findings highlighted the complex immune regulatory network in response to C.irritans infection,offering references for prevention and control of white spot disease in yellowfin seabream. 展开更多
关键词 Cryptocaryon irritans yellowfin seabream morphology TRANSCRIPTOME PROTEOME immune response
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Influence of Honey on Structural,Morphology and Thermal Behavior of Zein-Based Polymer Systems
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作者 Nurrul Asyiqin K.Shamsuri Shujahadeen B.Aziz +2 位作者 Siti Nadiah Halim Hashlina Rusdi Mohd Fakhrul Zamani Kadir 《Journal of Polymer Materials》 2025年第4期1111-1123,共13页
This study investigates the effects of honey concentration on the crystallinity,morphology,and thermal behavior of zein-based polymer systems,aiming to assess honey’s role as a natural plasticizer.Fourier transform i... This study investigates the effects of honey concentration on the crystallinity,morphology,and thermal behavior of zein-based polymer systems,aiming to assess honey’s role as a natural plasticizer.Fourier transform infrared spectroscopy(FTIR)analysis confirmed the presence of strong intermolecular interactions and hydrogen bonding between zein and honey,indicating good miscibility.X-ray diffraction(XRD)patterns revealed a significant reduction in crystallinity with increasing honey concentration up to 25 wt.%,with the ZH5(75 wt.%zein-25 wt.%honey)sample exhibiting the smallest crystallite size(4.23 nm),suggesting enhanced amorphous character suitable for ionic mobility.Field emission scanning electron micrograph(FESEM)images of ZH5 displayed a homogeneous porousfiber-like morphology,while excess honey beyond 25 wt.%led to agglomeration and phase separation.Thermal analysis demonstrated improved thermal stability for ZH5,with a higher decomposition temperature and greater residual mass.Differential scanning calorimetry(DSC)results showed a single glass transition temperature(Tg)for ZH5 at 88.4℃,indicating good miscibility between honey and zein materials.These findings identify 25 wt.%honey as the optimal concentration for plasticization,modifying zein’s structure and enhancing its amorphous nature and thermal resilience.The results highlight the potential of honey as a sustainable and multifunctional plasticizer for the development of biodegradable and eco-friendly polymer electrolyte systems. 展开更多
关键词 HONEY ZEIN PLASTICIZER CRYSTALLINITY morphology
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Identification of Ichthyoplankton Species in the East China Sea off the Coast of Zhoushan Archipelago Using An Integrated Strategy of Morphology and DNA Barcoding
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作者 LIANG Zibin JIANG Rijin +3 位作者 MCHURA Magati Tereza YIN Rui ZHOU Yongdong CHEN Yongjiu 《浙江海洋大学学报(自然科学版)》 2025年第1期49-59,共11页
The East China Sea(ECS)off the Coast of Zhoushan Archipelago,Zhejiang(ECS-CZA)is home to abundant fishery resources and an important spawning,feeding,and nursing ground for a variety of fish species.Due to long-term o... The East China Sea(ECS)off the Coast of Zhoushan Archipelago,Zhejiang(ECS-CZA)is home to abundant fishery resources and an important spawning,feeding,and nursing ground for a variety of fish species.Due to long-term overfishing,the ichthyoplankton structure has been dramatically altered.Understanding the species composition and distribution of fish eggs and larvae is one of the most essential tasks to accurately regulate fishery resources and formulate effective management policies;however,little is known about the ichthyoplankton in this region.In this study,an integrated strategy of morphology identification(MI)and mitochondrial COI DNA barcoding was used to identify species of fish eggs and larvae collected from the ECSCZA.MI revealed 15 fish egg species belonging to 12 families and 12 fish larva species belonging to 12 families;in contrast,DNA barcoding altogether identified 30 species,including 18 fish egg species and 13 fish larva species.One species was shared between the egg and larva samples.Our study offers useful tools and critical scientific information for further understanding the diversity,distribution,and conservation management of various ichthyoplankton species in the marine environment. 展开更多
关键词 Zhoushan Archipelago ICHTHYOPLANKTON morphology DNA barcoding species diversity conservation management
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Correction to:Functional reproductive morphology of the snapping shrimp genus Synalpheus Spence Bate,1888(Decapoda,Alpheidae)
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《Current Zoology》 2025年第3期408-408,共1页
This is a correction to:Isabela R R Moraes,Mariana Antunes,Laura S Lopez-Greco,Fernando Jose Zara,Antonio Leao Castilho,Functional reproductive morphology of the snapping shrimp genus Synalpheus Spence Bate,1888(Decap... This is a correction to:Isabela R R Moraes,Mariana Antunes,Laura S Lopez-Greco,Fernando Jose Zara,Antonio Leao Castilho,Functional reproductive morphology of the snapping shrimp genus Synalpheus Spence Bate,1888(Decapoda,Alpheidae),Current Zoology,2024,71,338-352;https:/doi.org/10.1093/cz/zoae053. 展开更多
关键词 Synalpheus reproductive morphology ALPHEIDAE snapping shrimp DECAPODA
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Single‑Neuron Reconstruction of the Macaque Primary Motor Cortex Reveals the Diversity of Neuronal Morphology
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作者 Siyu Li Yan Shen +11 位作者 Yefei Chen Zexuan Hong Lewei Zhang Lufeng Ding Chao‑Yu Yang Xiaoyang Qi Quqing Shen Yanyang Xiao Pak‑Ming Lau Zhonghua Lu Fang Xu Guo‑Qiang Bi 《Neuroscience Bulletin》 2025年第3期525-530,共6页
Dear Editor,The primary motor cortex,also known as MOp in rodents,F1,or M1 in primates[1],plays a crucial role in autonomous motor control.It is interconnected with other motor control structures such as the basal gan... Dear Editor,The primary motor cortex,also known as MOp in rodents,F1,or M1 in primates[1],plays a crucial role in autonomous motor control.It is interconnected with other motor control structures such as the basal ganglia,thalamus,and brainstem.Among these connections,the corticostriatal system plays a significant role in functions including action selection,motor control,sequence learning,and habit formation[2]. 展开更多
关键词 habit formation autonomous motor controlit morphology action selectionmotor corticostriatal system NEURON basal gangliathalamusand primary motor cortexalso
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The morphology across tourism destinations:A case study in China
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作者 ZHENG Yunhao LIU Zheyi +4 位作者 ZHANG Yi Teemu MAKKONEN JIANG Yanxiao JIANG Kaifeng LIU Yu 《Journal of Geographical Sciences》 2025年第11期2467-2489,共23页
Morphology,the study of shapes or forms,when applied to tourism,emphasizes the multifarious spatial practices between morphological elements and tourism activities.However,existing literature on morphology in the cont... Morphology,the study of shapes or forms,when applied to tourism,emphasizes the multifarious spatial practices between morphological elements and tourism activities.However,existing literature on morphology in the context of tourism usually only focuses on a single or a limited number of study areas,overlooking common or even universal patterns across various tourism destinations.To address this gap,we utilize geospatial big data and present a case study on the morphology of 406“AAAAA”-rated scenic areas in China.A framework based on“points”,“lines”,“planes”,and“solids”was designed to systematically organize and analyze morphological elements across scenic areas.The findings provide valuable insights for tourism planning and development,such as the co-occurrence of dense road networks and fragmented landscapes within scenic areas,as well as the resourcecontext-influenced(cultural or natural)associations between morphological features and tourism indicators.This research provides valuable strategic guidance for more effective and informed tourism development while acknowledging the trade-offs between generalizability and local specificity. 展开更多
关键词 morphology tourism planning DESTINATIONS geospatial big data China
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Evolution of shoal and deep-water channel morphology and responses to human activities in the downstream section of the terminal hub of the Hanjiang River
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作者 Yunping Yang Jinhai Zheng +3 位作者 Lingling Zhu Hongqian Zhang Biao Li Jianjun Wang 《River》 2025年第3期400-415,共16页
The operation of cascade reservoirs in a watershed profoundly exerts river watersediment dynamics and topography evolution,and the terminal reservoir is the focus area for river and waterway management.This paper reve... The operation of cascade reservoirs in a watershed profoundly exerts river watersediment dynamics and topography evolution,and the terminal reservoir is the focus area for river and waterway management.This paper reveals the process and underlying factors of topography evolution and water level adjustment in the lower Hanjiang River under the action of cascade reservoirs.This study focused on the 263 km river channel downstream of the Xinglong Hydropower Conservancy Project on the Hanjiang River.Using measured flow,sediment,and topography data from 1977 to 2023,we analyzed the changing characteristics of riverbed scouring and deposition intensity,thalweg,and cross-sections.Additionally,we evaluated the response relationship between riverbed scouring and deposition intensity and factors such as sediment transport,runoff,and human activities.From 1977 to 2023,the low-water channel in the Xinglong-Estuary reaches showed a scouring and cutting tendency,and the riverbed slop initially decreased and then increased.The main cause of the riverbed scouring along the Xinglong-Estuary reaches was the reduced sediment load in the watershed,with waterway engineering having a slightly larger influence than runoff in the Xinglong-Xiantao reaches;by contrast,runoff exerted a more significant effect than both waterway engineering and the Yangtze River water level decline in the Xiantao-Estuary reaches.During the autumn flood season from 1983 to 2023,the water level differences between the Hanjiang and Yangtze Rivers at the same flow rate showed an increasing trend,leading to an increase in water surface slope,which intensified scouring forces and riverbed scouring.This study improves our understanding of the impacts of dam construction on river topographical evolution,water level changes,and deep‐water waterway resources. 展开更多
关键词 bank-channel morphology cascade reservoirs riverbed deposition riverbed scouring sediment conditions water conditions waterway engineering
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Three-dimensional characterization of particle morphology in natural gravel and blasted rock fragments using SfM-MVS photogrammetry
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作者 Hongchen Liu Zitao Zhang +2 位作者 Huaizhi Su Xuedong Zhang Jing Hu 《River》 2025年第1期70-83,共14页
This study aims to develop a high-precision and cost-efficient method for the threedimensional reconstruction of large particles in natural gravel and blasted rock fragments,utilizing Structure from Motion(SfM)and Mul... This study aims to develop a high-precision and cost-efficient method for the threedimensional reconstruction of large particles in natural gravel and blasted rock fragments,utilizing Structure from Motion(SfM)and Multi-View Stereo(MVS)techniques.The proposed approach was applied to characterize the three-dimensional morphology of rockfill dam materials at a real construction site.Particle shape was quantitatively analyzed using shape indices of sphericity,convexity,and angularity.The predominant morphology of natural gravel is characterized as slightly elongated and slightly flat,while rock fragments are slightly elongated and not flat.Probability density distributions of shape indices follow a skewed normal distribution:sphericity and convexity show leftward skewness,whereas angularity is right-skewed.Skewness parameters of sphericity and angularity are consistent between natural gravel and blasted rock fragments,indicating comparable shape asymmetry.Convexity skewness is significantly higher in natural gravel compared to rock fragments,by approximately an order of magnitude.The relationship between size and particle shape shows that form ratios and associated shape descriptors change linearly with the logarithm of size;larger particles approach spherical or cubic forms.The innovative measurements contribute to the particle shape data set of rockfill dam materials,providing valuable insights into the three-dimensional and statistical morphological characteristics of relatively large particles in natural gravel and blasted rock fragments.This approach enhances understanding of particle morphology's impact on the mechanical behavior of granular materials. 展开更多
关键词 3D reconstruction ANGULARITY CONVEXITY particle morphology shape form
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Deep learning approach for morphology classification and particle sizing of industrial methanol-to-olefins(MTO)catalyst
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作者 Qingyu Wang Duiping Liu +3 位作者 Yong Lu Jibin Zhou Xiangang Ma Mao Ye 《Chinese Journal of Chemical Engineering》 2025年第8期1-10,共10页
Accurately acquiring catalyst size and morphology is essential for supporting catalytic reaction process design and optimal control. We report an intelligent catalyst sizing and morphological classification method bas... Accurately acquiring catalyst size and morphology is essential for supporting catalytic reaction process design and optimal control. We report an intelligent catalyst sizing and morphological classification method based on the Mask-RCNN framework. A dataset of 9880 high-resolution images was captured by using a self-made fiber-optic endoscopic system for 13 kinds of silicoaluminophosphate-34 (SAPO-34) catalyst samples with different coke. Then there were approximately 877881 individual particles extracted from this dataset by our AI-based particle recognition algorithm. To clearly describe the morphology of irregular particles, we proposed a hybrid classification criterion that combines five different parameters, which are deformity, circularity, roundness, aspect ratio, and compactness. Therefore, catalyst morphology can be classified into two categories with four types. The first category includes regular types, such as the spherical, ellipsoidal, and rod-shaped types. And all the irregular types fall into the second category. The experimental results showed that a catalyst particle tends to be larger when its coke deposition increased. Whereas particle morphology remained primarily spherical and ellipsoidal, the ratio of each type varied slightly according to its coke. Our findings illustrate that this is a promising approach to be developing intelligent instruments for catalyst particle sizing and classification. 展开更多
关键词 CATALYST Particle morphology Neural networks Particle size distribution Irregular particles
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Study on the regulation of Mortierella alpina morphology and high yield of arachidonic acid by metal ions
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作者 Yuanbang Feng Xin Zhang +2 位作者 Hua Yang Xue Feng Ming Chen 《Systems Microbiology and Biomanufacturing》 2025年第1期400-408,共9页
To achieve high production of arachidonic acid(ARA)through industrial fermentation of Mortierella alpina,the correlation between metal ions,mycelium pellet morphology and ARA production was investigated.By adding diff... To achieve high production of arachidonic acid(ARA)through industrial fermentation of Mortierella alpina,the correlation between metal ions,mycelium pellet morphology and ARA production was investigated.By adding different metal ions to the culture medium,observing the morphological differences of mycelium pellet,total oil production and ARA content and established a correlation between them.The results showed that adding sodium ions increase the density of mycelium pellet,while reducing the diameter of mycelium pellet,resulting in a 41.59%increase in ARA production.Potassium ions,magnesium ions,calcium ions and iron ions slightly reduce the diameter of fungal hyphae and increase ARA production by 7.47%,17.81%,36.05%and 9.37%,respectively.At the same time,calcium ions promoted the branching growth of mycelium,which solve the problem of excessive free mycelium in fermentation broth within a certain concentration range.Zinc ions had a negative impact on bacterial growth,leading to the formation of mycelium clumps in the fermentation broth.Manganese ions and ferrous ions could transform the morphology of fungal mycelium into a smooth spherical surface,which was not conducive to the growth of M.alpina and the accumulation of oil.The comprehensive results showed that the optimal fermentation mycelium form for M.alpina was a dense central and loosely packed mycelium pellet.The yield of ARA was directly proportional to the density of mycelium pellet and inversely proportional to the diameter of mycelium pellet. 展开更多
关键词 Mortierella alpina Metal ions Mycelium pellet morphology Arachidonic acid PRODUCTION
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Research on the Morphology and Mechanical Property of Bonding Interfaces Fabricated by Multimaterial Digital Light Processing
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作者 Yazhou Li Qiang Yang +5 位作者 Fu Wang Lingyun Jian Qianyuan Wang Jintao Xiao Tao Wu Dichen Li 《Additive Manufacturing Frontiers》 2025年第3期147-157,共11页
Multimaterial digital light processing(DLP)three-dimensional(3D)printing technology provides unique advantages in the field of multi material additive manufacturing(MM AM)with its high resolution and rapid shaping cap... Multimaterial digital light processing(DLP)three-dimensional(3D)printing technology provides unique advantages in the field of multi material additive manufacturing(MM AM)with its high resolution and rapid shaping capabilities based on photopolymerization.However,owing to differences in the curing behavior and physical properties of different materials,multimaterial DLP 3D printing faces challenges such as insufficient interfacial bonding strength and unstable mechanical properties.In this study,two resins were integrated by multimaterial DLP 3D printing technology,and the effects of different layer thicknesses and exposure times on the interfacial bonding strength and morphology of the multimaterials were systematically investigated.The interfacial bonding mechanisms of the two resins was analyzed.It was found that increasing the exposure time can improve the interfacial bonding strength between materials,but certain limitations exist.A mathematical model relating the interfacial bonding strength to the exposure time and layer thickness was developed,and optimal process parameters were determined using optimization algorithms.A variable-parameter printing strategy for the interface was proposed to further improve the performance of printed parts.The maximum tensile strength of the multimaterial samples(44.43 MPa)using this strategy reached that of single-material parts(45 MPa),validating the feasibility of this strategy.This provides guidance for multimaterial DLP 3D printing processes and offers valuable insights for the future additive manufacturing of high-performance multimaterial components. 展开更多
关键词 Multimaterial additive manufacturing Bonding interface morphology Mechanical properties Processing parameters
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