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Tensile deformation of fine-grained Mg at 4K,78K and 298K

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Journal of Magnesium and alloys 2024年第6期12卷 2534-2556页

作者： M.Walag A.Kula P.Noga T.Tokarski G.Cios M.Niewczas AGH University of Krakow Faculty of Non-Ferrous MetalsKrakowPoland AGH University of Krakow Academic Centre for Materials and NanotechnologyKrakowPoland Materials Science and Engineering McMaster UniversityHamiltonCanada

The impact of grain size,ranging from 0.9μm to 9μm,on the mechanical properties of commercially pure Mg is investigated at temperatures of 4K,78K,and *** mechanisms governing plastic flow are influenced by both grain size and *** 4K and 78K,dominant deformation modes in Mg involve dislocation glide and extension twinning,regardless of grain *** interactions between basal and non-basal dislocations and dislocations with grain boundaries promote an unusually high rate of work hardening in the plastic regime,leading to premature *** yield stress follows the Hall-Petch relationshipσ_(y)∼k/√d,with the slope k increasing with decreasing *** 298K,in addition to dislocation glide and twinning,grain boundary sliding(GBS)becomes significant in samples with grain sizes below 3μm,considerably enhancing the material’s *** activation provides an additional recovery mechanism for dislocations accumulating at grain boundaries,facilitating their absorption during sliding and *** ofσrelationship suggests that the basal slip is the dominant dislocation mode in Mg at *** grain size suppresses dislocation activity and twinning and increases GBS,resulting in lowerandσ*** conventional deformation modes coupled with enhanced GBS yields stress softening,breaking down the Hall-Petch relationship in Mg below 3μm grain size,leading to an inverse Hall-Petch *** work reports new data on the strength,ductility,work hardening and fracture behaviour,and their variations with Mg grain size across different temperature regimes.

关键词： Polycrystalline Mg Mechanical properties Deformation mechanisms Work-hardening Texture evolution Cryogenic temperatures Hall-Petch relationship

Metamorphic P-T conditions and ages of garnet-biotite schists in the Dahongshan Group from the southwestern Yangtze Block

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Acta Geochimica 2024年第4期43卷 707-718页

作者： Jun-xiao Ma Guang-shu Yang Yong-feng Yan Xiao-Fei Xu Yun-hua Ren Hui Zhao Xiao-jun Zheng Yuan Qin faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China Geological Team 306 of Yunnan non-ferrous metals Geological Bureau Kunming 650217China Yunnan Provincial Bureau of non-ferrous Geology Kunming 650051China

The Dahongshan Group,situated at the southwestern margin of the Yangtze Block,represents a geological unit characterized by relatively high-grade metamorphism in the *** paper investigates the garnet-biotite schist from the Laochanghe Formation of the Dahongshan Group,employing an integrated approach that includes petrological analysis,phase equilibrium modeling,and zircon U-Pb *** schist is mainly composed of garnet,biotite,plagioclase,quartz,rutile,and *** equilibrium modeling revealed the peak metamorphic conditions of 8-9 kbar and 635-675°*** further integrating the prograde metamorphic profile of garnet and geothermobarometric results,a clockwise P-T metamorphic evolution path is constructed,which includes an increase in temperature and pressure during the prograde ***-ICP-MS zircon U-Pb dating and zircon Ti thermometry constrains the post-peak metamorphic age of 831.2±7.2 *** with previously reported results,it is revealed that the southwestern margin of the Yangtze Block experienced a large-scale regional metamorphism during the Neoproterozoic(890-750 Ma),which is related to the collisional orogenic *** may be associated with the late-stage assembly of the Rodinia supercontinent or with local compression and subduction processes during the breakup of the Rodinia supercontinent.

关键词： Southwestern Yangtze Block Dahongshan Group Phase equilibrium modeling Zircon U-Pb dating Neoproterozoic metamorphism

Flotation separation of scheelite from calcite using luteolin as a novel depressant

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 462-472页

作者： Xiaokang Li Ying Zhang Haiyang He Yu Wu Danyu Wu Zhenhao Guan faculty of Land and Resources Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Clean Utilization of Complex non-ferrous Metal Resources Kunming University of Science and TechnologyKunming 650093China

This paper proposes luteolin(LUT)as a novel depressant for the flotation-based separation of scheelite and calcite in a sodium oleate(NaOL)*** suitability of LUT as a calcite depressant is confirmed through micro-flotation *** pH=9,with LUT concentration of 50 mg·L^(-1) and NaOL concentration of 50 mg·L^(-1),scheelite recovery reaches 80.3%.Calcite,on the other hand,exhibits a recovery rate of 17.6%,indicating a significant difference in floatability between the two ***,the surface modifica-tions of scheelite and calcite following LUT treatment are characterized using adsorption capacity testing,Zeta potential analysis,Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),and atomic force microscopy(AFM).The study in-vestigates the selective depressant mechanism of LUT on *** capacity testing and Zeta potential analysis demonstrate sub-stantial absorption of LUT on the surface of calcite,impeding the further adsorption of sodium oleate,while its impact on scheelite is ***-IR and XPS analyses reveal the selective adsorption of LUT onto the surface of calcite,forming strong chemisorption bonds between the hydroxyl group and calcium ions *** directly illustrates the distinct adsorption densities of LUT on the two miner-al ***,LUT can effectively serve as a depressant for calcite,enabling the successful separation of scheelite and calcite.

关键词： scheelite calcite luteolin flotation depressant separation

Growth and inhibition of zinc anode dendrites in Zn-air batteries:Model and experiment

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Chinese Journal of Chemical Engineering 2024年第3期67卷 268-281页

作者： Cuiping He Qingyi Gou Yanqing Hou Jianguo Wang Xiang You Ni Yang Lin Tian Gang Xie Yuanliang Chen Kunming University of Science and Technology State Key Laboratory of Complex Nonferrous Metal Resources Clean UtilizationKunming 650093China Kunming University of Science and Technology Faculty of Metallurgical and Energy EngineeringKunming 650093China China Copper Co.Ltd KunmingYunnan 650051China State Key Laboratory of Advanced Metallurgy for non-ferrous metals Kunming 650051China Sichuan Shunying Power Battery Materials Co.Ltd Sichuan 620076China

Zinc(Zn)-air batteries are widely used in secondary battery research owing to their high theoretical energy density,good electrochemical reversibility,stable discharge performance,and low cost of the anode active material ***,the Zn anode also leads to many challenges,including dendrite growth,deformation,and hydrogen precipitation *** this context,Zn dendrite growth has a greater impact on the cycle *** this dissertation,a dendrite growth model for a Zn-air battery was established based on electrochemical phase field theory,and the effects of the charging time,anisotropy strength,and electrolyte temperature on the morphology and growth height of Zn dendrites were studied.A series of experiments was designed with different gradient influencing factors in subsequent experiments to verify the theoretical simulations,including elevated electrolyte temperatures,flowing electrolytes,and pulsed *** simulation results show that the growth of Zn dendrites is controlled mainly by diffusion and mass transfer processes,whereas the electrolyte temperature,flow rate,and interfacial energy anisotropy intensity are the main *** experimental results show that an optimal electrolyte temperature of 343.15 K,an optimal electrolyte flow rate of 40 ml·min^(-1),and an effective pulse charging mode.

关键词： Zn-air battery Zinc anode Zinc dendrite Simulated dendrite growth Inhibit dendrite growth Phase-field model

Copernicrinus zamorae *** ***.,the oldest thiolliericrinid crinoid(Crinoidea,Echinodermata) from the Bajocian strata of algeria,Africa

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Journal of Palaeogeography 2024年第2期13卷 237-251页

作者： Bartosz J.Pιachno Madani Benyoucef Fayc al Mekki Mohammed Adaci Imad Bouchemla Sreepat Jain Marcin Krajewski Mariusz A.Salamon faculty of Biology Institute of BotanyJagiellonian University in KrakowGronostajowa Street 930-387 KrakowPoland Laboratoire de Géomatique Ecologie et EnvironnementMustapha Stambouli University of MascaraDZ-29000 MascaraAlgeria Abou Bekr Belkaid University of Tlemcen TlemcenAlgeria Department of Geological Sciences Faculty of Biological and Agricultural SciencesMouloud Mammeri University of Tizi-OuzouTizi-OuzouAlgeria Adama Science and Technology University School of Applied Natural SciencesDepartment of Applied GeologyP.O.Box 1888AdamaEthiopia faculty of Geology Geophysics and Environmental ProtectionAGH University of Science and TechnologyAl.A.Mickiewicza 30PL-30-059KrakowPoland faculty of Natural Sciences University of Silesia in KatowiceBedzinska Street 60PL-41-200 SosnowiecPoland

The thiolliericrinids(Thiolliericrinidae) are comatulids(Comatulida),which retained their stalks as ***,we report a centrodorsal from the Bajocian strata(Middle Jurassic) of the Djebel Kérdacha area,northwestern algeria(Africa).It is the first thiolliericrinid report from outside of Europe and also the oldest representative of the Thiolliericrinidae whose first occurrence is from the *** crinoid is assigned to Copernicrinus zamorae *** *** reported new taxon shows strong similarities with the stemless ‘true’comatulids,Solanocrinites;the only difference is the presence of a facet to the stem in *** closest comparable thiolliericrinid to Copernicrinus is the Oxfordian Thiolliericrinus,interpreted as a descendant of the *** origin and overview of all thiolliericrinid representatives are also discussed herein.

关键词： Thiolliericrinidae Crinoids Coral facies Bajocian Jurassic algeria Southern Tethys margin

Microfacies and palaeoenvironments of lateCisuralian and Guadalupian(Early to MiddlePermian)alatoconchid-bearing limestone inLoei fold belt,Indochina Terrane

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Journal of Palaeogeography 2024年第3期13卷 453-474页

作者： Mongkol Udchachon Hathaithip Thassanapak Clive Burrett Seksan Chaidrusamee MichałKrobicki Pradit Nulay Center of Excellence in Basin Studies and Applied Palaeontology Palaeontological Research and EducationCenterMahasarakham UniversityMaha Sarakham 44150Thailand Department of Biology Faculty of ScienceMahasarakham UniversityMaha Sarakham 44150Thailand Department of General Geology and Geotourism Faculty of GeologyGeophysics and EnvironmentalProtectionAGH University of KrakowMickiewicza 3030-059 KrakowPoland Department of Mineral Resources Ministry of Natural Resources and EnvironmentRatchathewiBangkok10400Thailand

This study presents the first record of Early Permian alatoconchid bivalves from Thailand,theErawan section,in the north of Loei fold belt with prolific fusulines in association with gastropods,and *** taxa are dominated by Pseudofusulina *** Darvasites sp.,Staffella ***,Staffella sp.,Nankinella sp.,Neofusulinella sp.,Schubertella sp.,Pamirina darvasica,Pseudoendothyra *** others,indicating an Artinskian *** wackestone with common,well-preserved smaller foraminifers,Pseudovermiporella *** ostracods indicates a restricted lagoon environment with low to moderate water *** fossils,along with well-preserved,articulated alatoconchids in life-position,suggest the autochthonous nature of the deposits in an intertidal *** the central part of the fold belt,the Pak Chong section exhibits intervals of alatoconchid biostromes *** build-ups of the alatoconchid biostromes with gregarious bivalves,in life-positionembedded in a micritic wackestone matrix,suggest their preferred life habit and *** bivalvecoquinites containing packed bivalve shells and fragments,however,indicate a high-energy *** rockfabric along with common fusuline storm sheets suggests occasional storm events in a restricted,with moderate water circulation to open lagoon *** are predominated by staffellids and othersincluding Staffella sphaerica,Staffella sp.,Sphaerulina croatica,Pisolina subsphaerica,Nankinella sp.,Neoschwagerina simplex,Presumatrina sp.,Afghanella *** others,indicating a Wordian(Middle Permian)*** the southern portion of the fold belt along the Thai-Cambodian border,the Khao Taa Ngog sectioncontains limestone with alatoconchid shells with massive rugose corals which formed local carbonate build-upsin high-energy open platform ***-sorted bioclasts with common fusuline tests,shell fragments and coated grains suggest an open marine,lagoon,back reef

关键词： Indochina terrane Carbonate build-ups Microfacies Permian Depositional environment

Adaptive Segmentation for Unconstrained Iris Recognition

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Computers, Materials & Continua 2024年第2期78卷 1591-1609页

作者： Mustafa alRifaee Sally almanasra Adnan Hnaif Ahmad althunibat Mohammad Abdallah Thamer alrawashdeh faculty of Architecture and Design Al-Zaytoonah University of JordanAmman11733Jordan faculty of Computer Studies Arab Open UniversityRiyadh11681Saudi Arabia faculty of Science and Information Technology Al-Zaytoonah University of JordanAmman11733Jordan

In standard iris recognition systems,a cooperative imaging framework is employed that includes a light source with a near-infrared wavelength to reveal iris texture,look-and-stare constraints,and a close distance requirement to the capture *** these conditions are relaxed,the system’s performance significantly deteriorates due to segmentation and feature extraction ***,a novel segmentation algorithm is proposed to correctly detect the pupil and limbus boundaries of iris images captured in unconstrained ***,the algorithm scans the whole iris image in the Hue Saturation Value(HSV)color space for local maxima to detect the sclera *** image quality is then assessed by computing global features in red,green and blue(RGB)space,as noisy images have heterogeneous *** iris images are accordingly classified into seven categories based on their global RGB *** the classification process,the images are filtered,and adaptive thresholding is applied to enhance the global contrast and detect the outer iris ***,to characterize the pupil area,the algorithm scans the cropped outer ring region for local minima values to identify the darkest area in the iris *** experimental results show that our method outperforms existing segmentation techniques using the UBIRIS.v1 and v2 databases and achieved a segmentation accuracy of 99.32 on UBIRIS.v1 and an error rate of 1.59 on UBIRIS.v2.

关键词： Image recognition color segmentation image processing localization

CMTJ:Simulation package for analysis of multilayer spintronic devices

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npj Computational Materials 2023年第1期9卷 1804-1813页

作者： Jakub Mojsiejuk Sławomir Ziętek Krzysztof Grochot Witold Skowroński Tomasz Stobiecki Institute of Electronics AGH University of Science and TechnologyAl.Mickiewicza 30Kraków 30-059Poland faculty of Physics and Applied Computer Science AGH University of Science and TechnologyAl.Mickiewicza 30Kraków 30-059Poland

We present CMTJ—a simulation package for large-scale macrospin analysis of multilayer spintronics *** from conventional simulations,such as magnetoresistance and magnetisation hysteresis loops,CMTJ implements a mathematical model of dynamic experimental techniques commonly used for spintronics devices characterisation,for instance:spin diode ferromagnetic resonance,pulse-induced microwave magnetometry,or harmonic Hall voltage *** find that macrospin simulations offer a satisfactory level of agreement,demonstrated by a variety of *** a unified simulation package,CMTJ aims to accelerate wide-range parameter search in the process of optimising spintronics devices.

关键词： multilayer analysis hysteresis

Modeling the effect of stand and site characteristics on the probability of mistletoe infestation in Scots pine stands using remote sensing data

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Forest Ecosystems 2024年第3期11卷 296-306页

作者： Luiza Tymińska-Czabańska Piotr Janiec Pawel Hawrylo Jacek Slopek Anna Zielonka Pawel Netzel Daniel Janczyk Jaroslaw Socha Department of Forest Resources Management Faculty of ForestryUniversity of Agriculture in KrakowAl.29 Listopada 46Krakow31-425Poland Forest Management and Geodesy Bureau Ul.Lesnikow 2105-090Sekocin StaryPoland Department of Geoinformatics and Cartography Institute of Geography and Regional DevelopmentFaculty of Earth Sciences and Environmental ManagementUniversity of WroclawPl.Uniwersytecki 1WroclawPoland Institute of Geography and Spatial Management Faculty of Geography&GeologyJagiellonian University in KrakowUl.Gronostajowa 730-387Poland Torun Regional Directorate of State Forests Ul.Adama Mickiewicza 987-100TorunPoland

Over the past decade,the presence of mistletoe(Viscum album ***)in Scots pine stands has increased in many European *** the factors that influence the occurrence of mistletoe in stands is key to making appropriate forest management decisions to limit damage and prevent the spread of mistletoe in the ***,the main objective of this study was to determine the probability of mistletoe occurrence in Scots pine stands in relation to stand-related endogenous factors such as age,top height,and stand density,as well as topographic and edaphic *** used unmanned aerial vehicle(UAV)imagery from 2,247 stands to detect mistletoe in Scots pine stands,while majority stand and site characteristics were calculated from airborne laser scanning(alS)*** on stand age and site type from the State Forest database were also *** found that mistletoe infestation in Scots pine stands is influenced by stand and site *** documented that the densest,tallest,and oldest stands were more susceptible to mistletoe *** type and specific microsite conditions associated with topography were also important factors driving mistletoe *** addition,climatic water balance was a significant factor in increasing the probability of mistletoe occurrence,which is important in the context of predicted temperature increases associated with climate *** results are important for better understanding patterns of mistletoe infestation and ecosystem functioning under climate *** an era of climate change and technological development,the use of remote sensing methods to determine the risk of mistletoe infestation can be a very useful tool for managing forest ecosystems to maintain forest sustainability and prevent forest disturbance.

关键词： Generalized additive models Tree infestation Mistletoe occurrence alS UAV Scots pine