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Journal of Magnesium and Alloys 2021年第3期9卷 1007-1018页

作者： L.B.tong J.H.Chu w.t.sun Z.H.Jiang D.N.Zou S.F.Liu S.Kamado M.Y.Zheng School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of Materials Science and Engineering Jilin UniversityChangchun 130025China Department of Mechanical Engineering Nagaoka University of TechnologyNagaoka 940-2188Japan

In the current study,a homogenous ultra-fine grained microstructure with average grain size of 1.0μm is achieved in the Mg-Zn-Ca-Mn alloy through the reduplicative equal channel angular pressing(ECAP)at 300℃,and the mechanical properties are remarkably improved,with room-temperature yield strength of 269.6 MPa and elongation of 22.7%.the twinning deformation results in a discontinuous recrystallization behavior in the initial stage of *** further deformation,the continuously dynamic recrystallization contributes to an obvious grain refinement *** activation of non-basal slip system leads to the formation of a unique basal texture,which is related to the elevated ECAP temperature and the decreased grain *** grain refinement and texture modification derived from ECAP process result in the increase of yield strength,while the cracked secondary phase particles are beneficial to the enhanced ductility,through reducing the stress concentration and hindering premature failure.

关键词： Mg alloy ECAP Microstructural evolution High strength Superior ductility

Advances in oral mesenchymal stem cell-derived extracellular vesicles in health and disease

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Genes & Diseases 2024年第1期11卷 346-357页

作者： Huanyu Luo Anahid Ahmadi Birjandi Feilong Ren tianmeng sun Paul t.Sharpe Hongchen sun Zhengwen An Department of Oral Biology Jilin Provincial Key Laboratory of Tooth Development and Bone RemodelingSchool and Hospital of StomatologyJilin UniversityChangchunJilin 130021China Faculty of Dentistry Oral&Craniofacial SciencesCentre for Craniofacial and Regenerative BiologyKing's College LondonLondonSE19RTUK Department of Oral Pathology Jilin Provincial Key Laboratory of Tooth Development and Bone RemodelingSchool and Hospital of StomatologyJilin UniversityChangchunJilin 130021China

Extracellular vesicles(EVs)are nano-size vesicles secreted naturally by all cells into the extracellular space and have been recognized as important cell-cell mediators in multicel-lular *** contain nucleic acids,proteins,lipids,and other cellular components,regulating many basic biological processes and playing an important role in regenerative med-icine and *** can be traced to their cells of origin and exhibit a similar ***,EVs demonstrate low immunogenicity,good biocompatibility,and fewer side ef-fects,compared to their parent *** stem cells(MsCs)are one of the most important resource cells for EVs,with a great capacity for self-renewal and multipotent differ-entiation,and play an essential role in stem cell *** mechanism of MsC therapy was thought to be attributed to the differentiation of MsCs after targeted migration,as previously ***,emerging evidence shows the previously unknown role of MsC-derived para-crine factors in stem cell *** EVs derived from oral tissue MSCs(OMSC-EVs),show more advantages than those of all other MsCs in tissue repair and regeneration,due to their lower invasiveness and easier accessibility for sample ***,we systematically review the biogenesis and biological characteristics of OMSC-EVs,as well as the role of OMsC-EVs in intercellular ***,we discuss the potential therapeutic roles of OMSC-EVs in oral and systemic *** highlight the current challenges and future directions of OMSC-EVs to focus more attention on clinical *** aim to provide valuable insights for the explorative clinical application of OMSC-EVs.

关键词： Disease Extracellular vesicles Oral tissue MSC therapeutic application tissue regeneration

Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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Journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.t.Jeong S.w.Lee w.J.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

the superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain growth

Compressive property and energy absorption characteristic of interconnected porous Mg-Zn-Y alloys with adjusting Y addition

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Journal of Magnesium and Alloys 2024年第1期12卷 171-185页

作者： J.A.Liu S.J.Liu B.wang w.B.sun X.J.Liu Z.w.Han College of Materials Science and Engineering Key Laboratory of Automobile Materials(Ministry of Education)Jilin UniversityChangchun 130022PR China Key Laboratory of Bionic Engineering(Ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchun130022PR China weihai Institute for Bionics-Jilin University Weihai 264205PR China

In this study,interconnected porous Mg-2Zn-xY alloys with different phase compositions were prepared by various Y additions(x=0.4,3,and 6 wt.%)to adjust the compressive properties and energy absorption *** characterization methods were then applied to identify the microstructure of the porous Mg-Zn-Y and describe the details of the second *** tests were performed at room temperature(Rt),200℃,and 300℃to study the impact of the Y addition and testing temperature on the compressive properties of the porous *** experimental results showed that a high Y content promotes a microstructure refinement and increases the volume fraction of the second *** the Y content increases,different Mg-Zn-Y ternary phases appear:I-phase(Mg_(3)Zn_(6)Y),w-phase(Mg_(3)Zn_(3)Y_(2)),and LPSO phase(Mg_(12)ZnY).when the Y content ranges between 0.4%and 6%,the compressive strength increases from 6.30MPa to 9.23 MPa,and the energy absorption capacity increases from 7.33 MJ/m^(3)to 10.97 MJ/m^(3)at Rt,which is mainly attributed to the phase composition and volume fraction of the second ***,the average energy absorption efficiency is independent of the Y *** addition,the compressive deformation behaviors of the porous Mg-Zn-Y are altered by the testing *** compressive strength and energy absorption capacity of the porous Mg-Zn-Y decrease due to the softening effect of the high temperature on the *** deformation behaviors at different temperatures are finally observed to reflect the failure mechanisms of the struts.

关键词： Porous magnesium Rare earth elements Microstructure Compressive behavior Energy absorption characteristic

Divergent responses of runoff to climate change in the upper basins of the third Pole dominated by westerlies and monsoon

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Science China Earth Sciences 2024年第8期67卷 2592-2614页

作者： Qikai sun Fengge SU He sun State Key Laboratory of tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100101China

the diverse climates,distribution of snow and glaciers,and geographic locations directly affect the runoff response to climate change in the upper basins of the third *** present,a comprehensive analysis of runoff variations and their distinct responses to climate change in the westerlies-and monsoon-dominated upper basins is still *** study comprehensively analyzed annual runoff variations in westerlies-dominated basins(the upper basins of the Aksu(UAKS),Syr Darya(USRD),Yarkant(UYK),Hotan(UHt),Amu Darya(UAMD),and Indus(UI))and monsoon-dominated basins(the upper basins of the Yangtze(UYA),Yellow(UYE),Lancang(ULC),Nujiang(UNJ),and Yarlung Zangbo(UYZ))of the third Pole from 1961 *** multi-source meteorological data and large-scale circulation factors,this study investigated the divergent responses of runoff in the upper basins to climate change,and explored the large-scale circulation mechanisms underlying runoff variations in these upper *** results showed that:(1)the annual runoff in the majority of upper basins(except for the UYE and UYZ)exhibited an increasing trend,and the annual runoff in the UAKS,UYK,and UI showed a significant increasing trend from1961 to *** annual runoff in the upper basins of the third Pole changed abruptly from decreasing to increasing between the 1980s and 2000s,with the exception of the UYE.(2)the runoff in the monsoon-dominated upper basins has been controlled primarily by changes in precipitation over the past 55 *** contrast,the runoff in the westerlies-dominated upper basins exhibited three distinct long-term responses to climate change:temperature-dominated(UYK and UHt),precipitation-dominated(USRD and UAMD),and the combined influence of precipitation and temperature(UAKS and UI).Since the 1960s,the sensitivity of runoff to warm season temperature changes in the most westerlies-dominated upper basins has decreased,while the response of runoff to precipitation changes has intensified.(3)the stud

关键词： Upper basins of the third Pole Climate change westerlies and monsoon Runoff variations Large-scale circulation factors

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Fossil Equidae in the Linxia Basin with Biostratigraphic and Paleozoogeographic Significance

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 1-9页

作者： sun Boyang Key Laboratory of Vertebrate Evolution and Human Origins of the Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China

the Linxia Basin is characterized by an abundance of Cenozoic sediments,that contain exceptionally rich fossil *** are abundant in the Linxia Basin,the fossil record of equids in this region including 16 species that represent 10 *** comparison to other classic late Cenozoic areas in China,the Linxia Basin stands out,because the fauna and chronological data accompanying Linxia equids render them remarkably useful for *** anchitheriines in the region,such as Anchitherium and Sinohippus,represent early equids that appeared in the late stages of the middle and late Miocene,*** the equines,most species of Chinese hipparions have been identified in the Linxia Basin and some species of the genera Hipparion and Hippotherium have FAD records for ***,Equus eisenmannae is one of the earliest known species of Equus in the Old world and is well-represented at the Longdan *** species with precise geohistorical distributions can serve as standards for high-resolution chronological units within this *** at the eastern margin of the tibetan Plateau and subject to considerable uplift,the Linxia Basin has served as a biogeographic transition area for equids throughout the late Cenozoic.

关键词： Equidae Cenozoic biostratigraphy paleozoogeography Linxia Basin

Achieving simultaneously high conversion and high selectivity for light olefins directly producing from syngas

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Science China Chemistry 2024年第3期67卷 753-754页

作者： Yuhan sun Shanxi Research Institute Huairou Research LaboratoryTaiyuan 030032China Institute of Carbon Neutrality ShanghaiTech UniversityShanghai 201210China

the activity and selectivity are two primary indexes of a successful catalyst for chemical reactions. However,achieving a high activity and a high selectivity simultaneously is a long-standing challenge in catalysis, the socalled activity-selectivity trade-off. In the article recently published in Science, a research team led by Prof.

关键词： selectivity simultaneous catalysis

ONE-PARAMEtER FINItE DIFFERENCE MEtHODS AND tHEIR ACCELERAtED SCHEMES FOR SPACE-FRACtIONAL SINE-GORDON EQUAtIONS wItH DIStRIBUtED DELAY

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Journal of Computational Mathematics 2024年第3期42卷 705-734页

作者： tao sun Chengjian Zhang Haiwei sun School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory of Engineering Modeling and Scientific Computing Huazhong University of Science and TechnologyWuhan 430074China Department of Mathematics University of MacaoMacaoChina

this paper deals with numerical methods for solving one-dimensional(1D)and twodimensional(2D)initial-boundary value problems(IBVPs)of space-fractional sine-Gordon equations(SGEs)with distributed *** 1D problems,we construct a kind of oneparameter finite difference(OPFD)*** is shown that,under a suitable condition,the proposed method is convergent with second order accuracy both in time and *** implementation,the preconditioned conjugate gradient(PCG)method with the Strang circulant preconditioner is carried out to improve the computational efficiency of the OPFD *** 2D problems,we develop another kind of OPFD *** such a method,two classes of accelerated schemes are suggested,one is alternative direction implicit(ADI)scheme and the other is ADI-PCG *** particular,we prove that ADI scheme can arrive at second-order accuracy in time and *** some numerical experiments,the computational effectiveness and accuracy of the methods are further ***,for the suggested methods,a numerical comparison in computational efficiency is presented.

关键词： Fractional sine-Gordon equation with distributed delay One-parameter finite difference methods Convergence analysis ADI scheme PCG method

Dominant woody plant species recognition with a hierarchical model based on multimodal geospatial data for subtropical forests

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Journal of Forestry Research 2024年第3期35卷 111-130页

作者： Xin Chen Yujun sun State Forestry&Grassland Administration Key Laboratory of Forest Resources&Environmental Management Beijing Forestry UniversityBeijing 100083People's Republic of China

Since the launch of the Google Earth Engine(GEE)cloud platform in 2010,it has been widely used,leading to a wealth of valuable ***,the potential of GEE for forest resource management has not been fully *** extract dominant woody plant species,GEE combined Sen-tinel-1(S1)and Sentinel-2(S2)data with the addition of the National Forest Resources Inventory(NFRI)and topographic data,resulting in a 10 m resolution multimodal geospatial dataset for subtropical forests in southeast *** and texture features,red-edge bands,and vegetation indices of S1 and S2 data were computed.A hierarchical model obtained information on forest distribution and area and the dominant woody plant *** results suggest that combining data sources from the S1 winter and S2 yearly ranges enhances accuracy in forest distribution and area extraction compared to using either data source ***,for dominant woody species recognition,using S1 winter and S2 data across all four seasons was *** terrain factors and removing spatial correlation from NFRI sample points further improved the recognition *** optimal forest extraction achieved an overall accuracy(OA)of 97.4%and a maplevel image classification efficacy(MICE)of 96.7%.OA and MICE were 83.6%and 80.7%for dominant species extraction,*** high accuracy and efficacy values indicate that the hierarchical recognition model based on multimodal remote sensing data performed extremely well for extracting information about dominant woody plant *** the results using the GEE application allows for an intuitive display of forest and species distribution,offering significant convenience for forest resource monitoring.

关键词： Google Earth Engine Sentinel Forest resource inventory data Dominant woody plant species Subtropics Model performance

Organic thin-film transistors and related devices in life and health monitoring

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Nano Research 2024年第2期17卷 426-444页

作者： Chenfang sun tie wang tianjin Key Laboratory of Drug targeting and Bioimaging Life and Health Intelligent Research InstituteTianjin University of TechnologyTianjin 300384China

the early determination of disease-related biomarkers can significantly improve the survival rate of ***,a series of explorations for new diagnosis technologies,such as optical and electrochemical methods,have been devoted to life and health *** thin-film transistor(OtFt),as a state-of-the-art nano-sensing technology,has attracted significant attention from construction to application owing to the merits of being label-free,low-cost,facial,and rapid detection with multi-parameter ***,interference from non-specific adsorption is inevitable in complex biological samples such as body liquid and exhaled gas,so the reliability and accuracy of the biosensor need to be further improved while ensuring sensitivity,selectivity,and ***,we overviewed the composition,mechanism,and construction strategies of OtFts for the practical determination of disease-related biomarkers in both body fluids and exhaled *** results show that the realization of bio-inspired applications will come true with the rapid development of high-effective OtFts and related devices.

关键词： organic thin-film transistors biosensors biomarkers organic bioelectronics organic semiconductors healthcare