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journal of Magnesium and Alloys 2021年第2期9卷 560-568页

作者： b.j.Wang D.K.xu x.Cai Y.x.Qiao L.Y.Sheng School of Environmental and Chemical Engineering Shenyang Ligong UniversityShenyang110159China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiangChina Peking University Shenzhen InstituteShenzhen Key Lab Human Tissue Regenerate&RepairShenzhen 518057China

In this work,the influence of rolling ratios on microstructural changes and corrosion behavior of an as-rolled Mg-8 wt.%Li alloy in0.1 mol/L Na Cl solution has been *** revealed that with the rolling ratio being increased from 3 to 10,theα-Mg phases were elongated and fragmented,whilst the area fraction of exposedβ-Li phases ***,the corrosion performance of the alloy decreased with the increased rolling *** all the samples,their corrosion processes were quite similar and can have two *** the initial stage with the samples being immersed for less than 6 h,the corrosion mainly occurred inβ-Li *** the samples were immersed for longer than 6 h,the corrosion attack transferred toα-Mg phases and the hydrogen evolution rate was accelerated.

关键词： Mg-li alloys Wrought Microstructure Corrosion performance

RHEOCASTING OF A356 ALLOY bY LOW SUPERHEAT POURING WITH A SHEARING FIELD

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Acta Metallurgica Sinica(English Letters) 2006年第5期19卷 328-334页

作者： H.M. Guo x.j. Yang b. Hu Department of Materials Science and Engineering Nanchang UniversityNanchang 330031 China Department of Mechanical and Electronic Engineering Nanchang UniversityNanchang 330031 China

A novel semi-solid slurry-making process was developed, which was a controlled nucleation and growth technique using a specially designed rotational barrel. Experimental study was undertaken to investigate the effects of pouring temperature and rotation speed of barrel on the microstructure of A356 alloy. Localized rapid cooling, combined with vigorous mixing during the initial stage of solidification enhanced wall nucleation and nuclei survival. High nuclei density combined with a much gradual cooling afterwards led to the formation of the near-ideal semi-solid slurry under a large processing window for the pouring temperature. Primal. phase presented in mean equivalent diameter of 50-701μm and shape factor of 0.812-0.847, and featured zero-entrapped eutectic.

关键词： semi-solid processing nucleation grainsgrowth interfacestability

Plant triterpenoid saponins function as susceptibility factors to promote the pathogenicity of botrytis cinerea

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Molecular Plant 2024年第7期17卷 1073-1089页

作者： Francisco j.Escaray Amelia Felipo-benavent Cristian j.Antonelli begona balaguer Maria Pilar Lopez-Gresa Pablo Vera Instituto de biologia Molecular y Celular de Plantas Universidad Politecnica de Valencia-C.S.l.CCiudad Politecnica de la InnovacionEdificio 8Eacceso GIngeniero Fausto Elios/n46022ValenciaSpain

The gray mold fungus botrytis cinerea is a necrotrophic pathogen that causes diseases in hundreds of plant species,including high-value *** polyxenous nature and pathogenic success are due to its ability to perceive host signals in its *** this study,we found that laticifer cells of Euphorbia lathyris are a source of susceptibility factors required by *** to cause ***,poor-in-latex(pil)mutants,which lack laticifer cells,show full resistance to this pathogen,whereas lot-of-latex mutants,which produce more laticifer cells,are *** S factors are triterpenoid saponins,which are widely distributed natural products of vast structural *** downregulation of laticifer-specific oxydosqualene cyclase genes,which encode the first committed step enzymes for triterpene and,therefore,saponin biosynthesis,conferred disease resistance to ***,the Medicago truncatula Iha-1 mutant,compromised in triterpenoid saponin biosynthesis,showed enhanced ***,the application of different purified triterpenoid saponins pharmacologically complemented the diseaseresistant phenotype ofpil and hla-1 mutants and enhanced disease susceptibility in different plant *** found that triterpenoid saponins function as plant cues that signal transcriptional reprogramming in ***,leading to a change in its growth habit and infection strategy,culminating in the abundant formation of infection cushions,the multicellular appressoria apparatus dedicated to plant penetration and biomass destruction in *** together,these results provide an explanation for how plant triterpenoid saponins function as disease susceptibility factors to promote *** pathogenicity.

关键词： Euphorbia lathyris laticifer cell latex appressorium infection cushion necrotrophic fungi

识别液态和固态水的四波段水指数及其在咸海流域的应用

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中国科学：地球科学 2024年第3期54卷 788-807页

作者：岳兵陈曦李赛博杜正平 john WILSON 杨筠慧焦毅蒙黄双燕周成虎中国科学院新疆生态与地理研究所乌鲁木齐830011 中国科学院大学资源与环境学院北京100049 中国科学院地理科学与资源研究所北京100101 Spatial Sciences Institute University of Southern CaliforniaLos AngelesCA 90089-0374USA

虽然已有许多水指数被运用于咸海和咸海流域的水域面积分析,然而已有研究尚存在很大的不确定性.由于所使用水指数存在水体误识别的问题,导致不同研究得出的结论差异很大.此外,各种研究采用的咸海流域面积也差异很大,流域面积从约1百万km... 详细信息

虽然已有许多水指数被运用于咸海和咸海流域的水域面积分析,然而已有研究尚存在很大的不确定性.由于所使用水指数存在水体误识别的问题,导致不同研究得出的结论差异很大.此外,各种研究采用的咸海流域面积也差异很大,流域面积从约1百万km^(2)到2百万km^(2)不等.因此,我们首先界定咸海流域、锡尔河和阿姆河流域以及它们的上、中、下游的边界,然后提出可识别液态水和固态水的四波段指数(ILSW),以解决传统水指数的误别偏差问题.ILSW基于绿色、红色、近红外和热红外波段反射值,是归一化差异水指数(NDWI)和地表温度(LST)的合成.验证结果显示,ILSW水指数在咸海流域的准确性远远超过其他指数.研究结果表明,南咸海的水域面积平均每年缩小963km^(2),而北咸海几乎没有变化;由于气候变暖,咸海流域上游常年冰雪面积有大幅度退缩趋势,阿姆河上游和锡尔河上游常年冰雪的退缩速率分别为年均6233和384km^(2)/a.气候变化和人类活动引起了严重的水亏问题.自20世纪90年代以来,水亏呈增长趋势,平均每年增长3.778亿m^(3).2011~2020年期间,整个咸海流域平均总水亏量为76.967亿m^(3),而锡尔河流域上游(咸海流域的一个组成部分)水盈余量为25.461亿m^(3).研究结果对制定咸海流域可持续发展战略具有重要意义.

关键词：咸海流域锡尔河流域阿姆河流域水指数水面积覆盖水亏缺气候变化

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DETERMINATION OF CREEP PROPERTIES OF THERMAL bARRIER COATING(TbC)SYSTEMS FROM THE INDENTATION CREEP TESTING WITH ROUND FLAT INDENTERS

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 503-508页

作者： b.Zhao b.x.xu j.Liu Z.F.Yue School of Mechanics Civil Engineering and Architecture Northwestern Polytechnic University Xi'an710072 ChinaSchool of Mechanics Civil Engineering and Architecture Northwestern Polytechnic University Xi'an710072 ChinaSchool of Mechanics Civil Engineering and Architecture Northwestern Polytechnic University Xi'an710072 ChinaSchool of Mechanics Civil Engineering and Architecture Northwestern Polytechnic University Xi'an710072 China

Indentation creep behavior with cylindrical flat indenters on the thermal barrier coating (TbC) was studied by finite element method (FEM). On ike constant applied indentation creep stress, there is a steady creep rate for each case studied for different creep properties of the TbC system. The steady creep depth rate depends on the applied indentation creep stress and size of the indenters as well as the creep properties of the bond coat of the TbC and the substrate. The possibilities to determine the creep properties of a thermal barrier system from indention creep testing were discussed. As an example, with two different size indenters, the creep properties of bond coat of the TbC system can be derived by an inverse FEM method. This study not only provides a numerical method to obtain the creep properties of the TbC system, but also extends the application of indentation creep method with cylindrical flat indenters.

关键词： thermal barrier coating (TbC) system indention creep testing,finite element creep analysis determination of creep parameters,bond coat

Construction of 2D/2D Ti_(3)C_(2)T_(x)Mxene/CdS heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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journal of Materials Science & Technology 2024年第4期171卷 1-9页

作者： T.Y.Huang Z.Yang S.Y.Yang Z.H.Dai Y.j.Liu j.H.Liao G.Y.Zhong Z.j.xie Y.P.Fang S.S.Zhang Key Laboratory for biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor ***,a novel stable Ti_(3)C_(2)T_(x)Mxene/CdS heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)CdS nanosheets on 2D Mxene interface via a solvothermal *** exceptional light absorption properties of Mxene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of CdS *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure Heterostructure Photothermal effect Photocatalyst Hydrogen evolution

Simulations of deformation and damage processes of SiCp/Al composites during tension

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journal of Materials Science & Technology 2018年第4期34卷 627-634页

作者： j.F.Zhang x.x.Zhang Q.Z.wang b.L.xiao Z.Y.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China

The deformation, damage and failure behaviors of 17 vol.% SiCp/2009AI composite were studied by micro- scopic finite element （FE） models based on a representative volume element （RVE） and a unit cell. The RVE having a 3D realistic microstructure was constructed via computational modeling technique, in which an interface phase with an average thickness of 50 nm was generated for assessing the effects of interracial properties. Modeling results showed that the RVE based FE model was more accurate than the unit cell based one. based on the RVE, the predicted stress-strain curve and the fracture morphology agreed well with the experimental results. Furthermore, lower interface strength resulted in lower flow stress and ductile damage of interface phase, thereby leading to decreased elongation. It was revealed that the stress concentration factor of SiC was -2.0： the average stress in SiC particles reached -1200 MPa, while that of the composite reached -600 MPa.

关键词： Metal matrix composites (MMCs) Fracture Finite element (FE) analysis Interfacial strength Tensile strength Representative volume element (RVE)

Ab initio molecular dynamics study on the local structures in Ce_(70)Al_(30) and La_(70)Al_(30) metallic glasses

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Chinese Physics b 2018年第5期27卷 405-411页

作者： F x Li j b Kong M Z Li Department of Physics Beijing Key Laboratory of Opto-electronic Functional Materials ＆ Micro-nano Devices Renmin University of China Beijing 100872 China

Ab initio molecular dynamics simulations were performed to investigate the effect of similar elements on the shortto medium-range atomic packing features in Ce70Al30 and La70Al30 glass-forming alloys. 4 f electrons of Ce element in Ce70Al30 alloy were properly treated in electronic calculations. The local atomic structures in both alloys are qualitatively similar. However, the local environments of Al atoms in Ce70Al30 alloy show fluctuation with temperature in the cooling process, which could result from 4 f electrons of Ce elements. Surprisingly, the medium-range atomic packing features of Al atoms in both MGs are quite different, although Ce and La elements are similar. These findings are useful for understanding the enhanced glass-forming ability by similar element substitution in RE-based MGs from a medium-range structure perspective.

关键词： rare earth-based metallic glasses medium-range order molecular dynamics simulation

Microwave sintered porous CoCrFeNiMo high entropy alloy as an efficient electrocatalyst for alkaline oxygen evolution reaction

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journal of Materials Science & Technology 2021年第20期79卷 171-177页

作者： j.Tang j.L.xu Z.G.Ye x.b.Li j.M.Luo School of Materials Science and Engineering Nanchang Hangkong UniversityNanchang330063China

Developing efficient,stable and economical electrocatalyst for oxygen evolution reaction(OER)is a significant pathway to produce clean energy from water ***,the promising and highly efficient porous CoCrFeNiMo high entropy alloys(HEAs)were prepared by microwave sintering using Mg space *** to unique properties of high entropy alloys and abundant active surface area,the porous CoCrFeNiMo-20 Mg exhibits excellent catalytic performance and prominent electrochemical stability with a low overpotential of 220 mV to reach current density of 10 mA cm^(-2),a small Tafel slope of 59.0 mV dec^(-1) and long-term durability for 24 h in 1.0 M *** results of microstructure and element states indicate that crystal defects,porous structure and villous hydroxides are the reasons for high OER performance of the *** work not only provides a new way to prepare electrocatalysts,but also proves the important application of high entropy alloys in functional materials.

关键词： CoCrFeNiMo High entropy alloys Electrocatalysts Oxygen evolution reaction Microwave sintering Mg space holder

The Synthesis of a Novel Lignan

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Chinese Chemical Letters 2000年第11期11卷 971-974页

作者： Qi x.x. Chang j.b. Guo R.Y. Chen R.F. Chem. Dept. of Zhengzhou Univeristy Zhengzhou 450052 China Henan Institute of Chemistry Henan Academy Sciences Zhengzhou 450002 China

A short convenient synthesis of a novel lignan, 2-(3′,4′,5′-trimethyoxyphenyl)-1,3-dimethyl-6,7,8-trimethoxy- naphthalene has been accomplished by the condensation of key intermediates, 3,4,5-trimethoxybenzyl methy... 详细信息

关键词： UV Kbr IR The Synthesis of a Novel Lignan EtOH