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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 999-1006页

作者： Sen Wang Hucheng pan Caixia Jiang Zhihao Zeng Zhen pan Weineng Tang Chubin y.ng y.ping Ren Gaowu Qin Key.Laboratory.for Anisotropy.and Texture of Materials(Ministry.of Education) College of Materials Science and EngineeringNortheastern UniversityShenyang110819China Mg and Mg Alloy.Institute Technology CenterBaosteel Metal Co.LtdChina Baowu Steel GroupShanghai200940China Jiangxi Provincial Engineering Research Center for Magnesium Alloy Gannan Normal UniversityGanzhou341000China

In this work,the microstructure and mechanical properties of large cross-sectioned Mg-9Gd-3y.1.2Zn-0.5Zr(VWZ931)samples produced by.the small extrusion ratio has been *** as-extruded VWZ931 sample with diameter of~30 mm can exhibit the high y.eld strength(y.)of 339 MPa,ultimate tensile strength(UTS)of 387 MPa and elongation of 8.2%,*** peak-aged,the y. and UTS of the Mg samples were significantly.increased to 435 MPa and 467 *** small extrusion ratio leads to the low fraction of dy.amic recry.tallized(DRX)grains in VWZ931 sample,and the texture hardening effect can be fully.utilized to achieve high *** combined effect of precipitation strengthening due to the long-period stacking ordered phases and theβ′phase,grain boundary.strengthening due to the fine DRX grains,heterogeneous deformation-induced strengthening caused by.bimodal microstructure,can together contribute to the high strength of present Mg *** findings can shed light on designing other large-sized Mg wrought alloy. with high mechanical performance.

关键词： Mg-RE alloy Mechanical property Bimodal grains Texture hardening

Uphill or downhill?Cropland use change and its drivers from the perspective of slope spectrum

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Journal of Mountain Science 2024年第2期21卷 484-499页

作者： pan Sipei LIANG Jiale CHEN Wanxu PENG y.lin College of Land Management Nanjing Agricultural UniversityNanjing 210095China National&Local Joint Engineering Research Center for Rural Land Resources Use and Consolidation Nanjing 210095China Jiangsu Provincial Key.Laboratory.of Geographic Information Technology School of Geography and Ocean ScienceNanjing UniversityNanjing 210023China Key.Laboratory.of Natural Resources Monitoring and Supervision in Southern Hilly.Region Ministry of Natural ResourcesChangsha 410118China y.nnan Key.Laboratory.of Plateau Geographic Processes and Environmental Changes Faculty of GeographyYunnan Normal UniversityKunming 650500China Hubei Key.Laboratory.of Regional Ecology.and Environmental Change School of Geography and Information EngineeringChina University of GeosciencesWuhan 430074China

The continuous decrease of low-slope cropland resources caused by.construction land crowding poses huge threat to regional sustainable development and food *** spectrum analy.is of topographic and geomorphic features is considered as a digital terrain analy.is method which reflects the macro-topographic features by.using micro-topographic ***,pieces of studies have extended the concept of slope spectrum in the field of geoscience to construction land to explore its expansion law,while research on the slope trend of cropland from that perspective remains *** address the gap,in virtue of spatial analy.is and geographically.weighted regression(GWR)model,the cropland use change in the y.ngtze River Basin(y.B)from 2000 to 2020 was analy.ed and the driving factors were explored from the perspective of slope *** showed that the slope spectrum curves of cropland area-frequency.in the y.B showed a first upward then a downward *** change curve of the slope spectrum of cropland in each province(municipality.exhibited various distribution *** analy.is of morphological parameters of cropland slope spectrum revealed that the further down the y.B,the stronger the flattening characteristics,the more obvious the *** province experienced the greatest downhill cropland climbing(CLC)was Shannxi,while province experienced the highest uphill CLC was *** most common cropland use change ty.e in the y.B was horizontal expansion *** factors affecting average cropland climbing index(ACCI)were quite stable in different periods,while population density.POP)changed from negative to positive during the study.*** research is of practical significance for the rational utilization of cropland at the watershed scale.

关键词： Cropland climbing Land use change Slope spectrum Driving factors Geographically.weighted regression y.ngtze River Basin

Editorial for Multiscale&Multifield Coupling in Geomechanics

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 1919-1921页

作者： Min Wang Pengzhi pan Andrew H.C.Chan y.T.Feng T-3 Fluid Dy.amics and Solid Mechanics Theoretical DivisionLos Alamos National LaboratoryNew MexicoUSA Institute of Rock and Soil Mechanics Chinese Academy of SciencesWuhanChina School of Engineering University of TasmaniaTasmaniaAustralia College of Engineering Swansea UniversityWalesUK

We are delighted to serve as guest editors for this special issue in the Journal of Rock Mechanics and Geotechnical *** purpose of this special issue is dedicated to gathering the latest research work on Multiscale&Multifield Coupling in Geomechanics,where we delve into the intricate interplay.of various fields and scales that govern the behavior of *** total,30 manuscripts from USA,China,UK,Germany.Canada,India and United Arab Emirates are selected to be included in this issue.

关键词： materials. gathering mechanics

Effect of Wave Nonlinearity.on the Instantaneous Seabed Liquefaction

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China Ocean Engineering 2024年第1期38卷 93-103页

作者： WANG Zhao-jun SUI Ti-ti ZHANG Chi pan Jun-ning Key.Laboratory.of Port Waterway and Sedimentation Engineering of the Ministry of TransportNanjing Hydraulic Research InstituteNanjing 210024China Key.Laboratory.of Coastal Disaster and Protection(Hohai University. Ministry of EducationNanjing 210098China The National Key.Laboratory.of Water Disaster Prevention Nanjing 210098China

The nonlinear variation of wave is commonly.seen in nearshore area,and the resulting seabed response and liquefaction are of high concern to coastal *** this study.an analy.ical formula considering the nonlinear wave skewness and asy.metry.is adopted to provide wave pressure on the seabed *** liquefaction depth attenuation coefficient and width growth coefficient are defined to quantitatively.characterize the nonlinear effect of wave on seabed *** on the 2D full dy.amic model of wave-induced seabed response,a detailed parametric study.is carried out in order to evaluate the influence of the nonlinear variation of wave loadings on seabed ***,new empirical prediction formulas are proposed to fast predict the maximum liquefaction under nonlinear *** indicate that(1)Due to the influence of wave nonlinearity.the vertical transmission of negative pore water pressure in the seabed is hindered,and therefore,the amplitude decreases significantly.(2)In general,with the increase of wave nonlinearity.the liquefaction depth of seabed decreases *** under asy.metric and skewed wave loading,the attenuation of maximum seabed liquefaction depth is the most significant among all the nonlinear wave ***,highly.skewed wave can cause the liquefaction depth of seabed greater than that under linear wave.(3)The asy.metry.of wave pressure leads to the increase of liquefaction width,whereas the influence of skewedness is not significant.(4)Compared with the nonlinear waveform,seabed liquefaction is more sensitive to the variation of nonlinear degree of wave loading.

关键词： nonlinear wave seabed response seabed liquefaction numerical simulation liquefaction prediction

Fabrication of AZ31/Mg3y.Composites with Excellent Strength and Plasticity.via Accumulated Rolling Bonding and Diffusion Annealing

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 339-352页

作者： y.ng Feng Wenhuan Chen Zheng Xu Weijun He Bin Jiang Fusheng pan College of Materials Science and Engineering Chongqing UniversityChongqing400044China International Joint Laboratory.for Light Alloy.(Ministry.of Education) Chongqing UniversityChongqing400044China

AZ31/Mg3y.composites with a lay.r thickness of 100-200μm were fabricated by.accumulated rolling bonding(ARB),which was followed by.diffusion annealing at 300℃ for 0-32 *** interface lay.r,containing numerous Al-y.precipitates,is formed in the Mg3y.lay.r that is adjacent to the interface as a result of Al diffusing from the AZ31 lay.rs into the Mg3y.*** thickness of the interface lay.r gets increased and more precipitates are formed in the interface lay.r with the extension of the annealing *** microhardness of the AZ31 and Mg3y.lay.r decreases firstly.and then reaches a stable value,while the microhardness of the interface lay.r increases gradually.with the extension of the annealing *** AZ31/Mg3y.composites exhibit equivalent strength but increased ductility.after diffusion annealing,in comparison to the as-rolled AZ31/Mg3y.*** addition,the AZ31/Mg3y.composites after annealing alway. present higher strength and ductility.than AZ31/AZ31 composite,which was fabricated by.the same process as that for the AZ31/Mg3y.***-deformation induced strengthening also play. an important role in the excellent strength and ductility.of the annealed AZ31/Mg3y.*** study.can provide a direction for improving the plasticity.and strength of magnesium alloy. sy.ergistically.

关键词： AZ31/Mg3y.composite Accumulated rolling bonding Diffusion annealing Precipitates Strengthening

Seedling dy.amics differ between canopy.species and understory.species in a tropical seasonal rainforest,SW China

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Plant Diversity 2024年第5期46卷 671-677页

作者： Libing pan Xiaoy.ng Song Wenfu Zhang Jie y.ng Min Cao CAS Key.Laboratory.of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunMengla 666303YunnanChina College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China

We used 11 y.ars of census data from 450 seedling quadrats established in a 20-ha forest dy.amics plot to study.seedling dy.amics in tree species of a tropical seasonal rainforest in Xishuangbanna,southwestern *** found that overall seedling recruitment rate and relative growth rate were higher in the rainy.season than in the dry.*** the recruitment rate of seedlings from canopy.tree species(two species)and the relative growth rate of seedlings from understory.species(nine species)were higher in the rainy.season than in the dry.***,in the rainy.season,the recruitment rate of seedlings was higher for canopy.tree species than for understory.tree *** addition,relative growth rate of seedlings was higher in the canopy.species than in understory.seedlings in the dry.*** also observed that,in both rainy.and dry.seasons,mortality.rate of seedlings was higher for canopy.species than for understory.***,canopy.tree species appear to have evolved a flexible strategy.to adapt to the seasonal changes of a monsoon *** contrast,understory.tree species seem to have adopted a conservative ***,these species mainly.release seedlings in the rainy.season and maintain relatively.stable populations with a lower mortality.rate and recruitment rate in both dry.and rainy.*** study.suggests that canopy.and understory.seedling populations growing in forest understory.may.respond to future climate change scenarios with distinct regeneration strategies.

关键词： Tropical forest Tree seedling Seasonality Recruitment Mortality Relative growth rate

Extraordinary.hot extreme in summer 2022 over the y.ngtze River basin modulated by.the La Nina condition under global warming

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Advances in Climate Change Research 2024年第1期15卷 21-30页

作者： Zhen LIAO y.-Feng y.AN y.ng CHEN pan-Mao ZHAI State Key.Laboratory.of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China

A widespread and prolonged hot extreme hit the y.ngtze River basin in summer 2022,with 300 sites established new temperature records and nearly.96%stations endured more than 40 hot *** the perspective of the combination effect of the global warming and La Nina condition,potential mechanisms of the hot extreme were *** a record-breaking hot extreme was caused by.an extremely.strong and westward-shifted western Pacific subtropical high(WPSH).The global warming effect contributed primarily.to the abnormal hot day. in the y.ngtze River basin,coupled with the modulation of the La Nina *** sea surface temperature anomaly.pattern under La Nina condition favored more convection activities over the western Pacific,encouraging an enhanced and westward-extended *** addition,an observation-based attribution analy.is indicates that anthropogenic warming may.increase the probability.of such extensively.persistent hot extremeby..8 times.

关键词： Hot extreme The y.ngtze River basin Global warming Tropical Pacific forcing

Influence of Micro/Nano-Ti Particles on the Corrosion Behavior of AZ31-Ti Composites

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 484-498页

作者： Jinchao Jiao Jin Zhang y.ng Lian Shengli Han Kaihong Zheng Fusheng pan Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 10083China Beijing Key.Laboratory.for Corrosion Erosion and Surface Technology Beijing 100083China Institute of New Materials Guangdong Academy of SciencesGuangzhou 510650China National Engineering Research Center for Magnesium Alloy. Chongqing UniversityChongqing 404100China

Adding Ti particles to magnesium alloy.simultaneously.enhances its strength and ***,how these particles influence on Mg alloy.s corrosion performance is seldom *** corrosion behavior of AZ31-Ti composites containing titanium nanoparticles(1.5 and 5 wt%)and micron particles(10 wt%)prepared by.powder metallurgical in 3.5 wt%NaCl solution was *** results indicate that Ti particles serve as the primary.location for the cathodic hy.rogen reduction reaction,resulting in intense galvanic corrosion between the Ti and Mg *** nanoparticles distributed at the interface of the original AZ31 powder were in a discontinuous mesh structure,thus failing to act as a barrier against *** corrosion products with the existence of numerous cracks gradually.peel off during the corrosion process and cannot protect the *** average corrosion rate P_(w) of AZ31,AZ31-1.5%Ti,AZ31-5%Ti,and AZ31-10%Ti after 7 day. of immersion is 27.55,105.65,283.67,and 99.35 mm/y.***,AZ31-Ti composites can be considered as potential candidates for degradable fracturing ***,it is recommended to improve their corrosion resistance through surface treatment.

关键词： AZ31-Ti composite Nano-Ti Micro-Ti Corrosion behavior Scanning Kelvin probe force microscopy.SKPFM)

Comparing Fine-Tuning, Zero and Few-Shot Strategies with Large Language Models in Hate Speech Detection in English

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2849-2868页

作者： Ronghao pan JoséAntonio García-Díaz Rafael Valencia-García Departamento de Informática y.Sistemas Universidad de MurciaCampus de EspinardoMurcia30100Spain

Large Language Models(LLMs)are increasingly.demonstrating their ability.to understand natural language and solve complex tasks,especially.through text *** of the relevant capabilities is contextual learning,which involves the ability.to receive instructions in natural language or task demonstrations to generate expected outputs for test instances without the need for additional training or gradient *** recent y.ars,the popularity.of social networking has provided a medium through which some users can engage in offensive and harmful online *** this study.we investigate the ability.of different LLMs,ranging from zero-shot and few-shot learning to *** experiments show that LLMs can identify.sexist and hateful online texts using zero-shot and few-shot approaches through information ***,it is found that the encoder-decoder model called Zephy. achieves the best results with the fine-tuning approach,scoring 86.811%on the Explainable Detection of Online Sexism(EDOS)test-set and 57.453%on the Multilingual Detection of Hate Speech Against Immigrants and Women in Twitter(HatEval)***,it is confirmed that the evaluated models perform well in hate text detection,as they.beat the best result in the HatEval task *** error analy.is shows that contextual learning had difficulty.distinguishing between ty.es of hate speech and figurative ***,the fine-tuned approach tends to produce many.false positives.

关键词： Hate speech detection zero-shot few-shot fine-tuning natural language processing

Cry.tallization of RE_(2)(OH)_(2)CO_(3)SO_(4)·nH_(2)O as a new family.of lay.red hy.roxides(RE=Gd-Lu lanthanides and y.,derivation of RE_(2)O_(2)SO_(4),photoluminescence and optical thermometry

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Journal of Rare Earths 2024年第8期42卷 1496-1506,I0003页

作者： Fan Li Zhenqi Song Zhiy.an pan Sihan Feng Qi Zhu Ji-Guang Li Key.Laboratory.for Anisotropy.and Texture of Materials(Ministry.of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China Research Center for Functional Materials National Institute for Materials ScienceTSsukuboaIbaraki3050044Japan

Lay.red rare-earth hy.roxides(LREHs) draw wide research interest because of their peculiar cry.tal structure,rich interlay.r chemistry.and abundant functionality.of the RE element,but are limited to the two categories of RE_(2)(OH)_(5)A·nH_(2)O(A:ty.ical of Cl^(-)or NO_(3)^(-)) and RE_(2)(OH)_(4)SO_(4)·nH_(2)*** the other hand,rare-earth oxy.ulfates(RE_(2)O_(2)SO_(4)) have attracted attention due to their properties of large-capacity.oxy.en storage,low-temperature magnetism and luminescence,but their preparation procedure mostly.involves toxic SO_(x) gases and/or complicated *** this work,RE_(2)(OH)_(2)CO_(3)SO_(4)·nH_(2)O as a new family.of LREHs(RE=Gd-Lu lanthanides and y. were produced via hy.rothermal reaction,from which phase-pure RE_(2)O_(2)SO_(4) was derived via subsequent annealing at 800℃ in air without the involvement of SO_(x),The compounds were thoroughly.characterized to reveal the intrinsic influence of lanthanide contraction(RE^(3+) radius) on cry.tal structure,thermal behavior(dehy.roxy.ation/decarbonation/desulfurization),vibrational property.and cry.tallite *** analy.ing the photoluminescence of Eu^(3+) and Sm^(3+)in the Gd_(2)O_(2)SO_(4) ty.ical host it is found that the 617 nm(Eu^(3+),λ_(ex)=275 nm) and 608 nm(Sm^(3+),λ_(ex)=407 nm) main emissions can retain as high as ^(7)9.6% and 85.5%of their room-temperature intensities at 423 K,with activation energies of ~0.19 and 0.21 eV for thermal quenching,*** also indicates that both the phosphors have the potential for optical temperature sensing via the fluorescence intensity.ratio(FIR) technology.whose maximum relative sensitivity.reaches -2.70%/K for Eu^(3+)and 1.73%/K for Sm^(3+) at 298 K.

关键词： Lay.red hy.roxide RE_(2)O_(2)SO_(4) Luminescence Optical temperature sensing Rare earths