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PREPARATION OF SEMI-SOLId AISi7Mg ALLOY SLURRY

Acta Metallurgica Sinica(English Letters) 2008年第2期21卷 139-145页

作者： z.d. z.ao W.M. Mao School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083China

In this article, semi-solid AlSiTMg alloy slurry was prepared by low superheat pouring and weak electromagnetic stirring. The effects of pouring temperature and stirring power on the microstructure of the AISiTMg alloy slurry were studied. The results showed that the semi-solid AISiTMg alloy slurry, 127 mm in diameter, could be prepared by using the low superheat pouring and weak electromagnetic stirring technology and this new technology could save energy and make the pouring process convenient. When the liquid AISiTMg alloy was poured at 650℃ or 630℃, the solidified micrastructure of the AISiTMg alloy slurry, prepared by weak electromagnetic stirring, was remarkably improved when compared with that of the slurry prepared without stirring. The primary α-Al grains appeared rosette-like or spherical. When the pouring temperature was decreased, the shape of the primary α-Al grains gradually changed from dendritic-like grains to spherical grains. When the pouring temperature was appropriately increased, that is, raised to a certain superheat, the pouring process became easier and an ideal spherical microstructure of the AISiTMg alloy slurry, prepared by weak electromagnetic stirring, could also be obtained. In this experiment, when the stirring power was 0.36 kW, the optimiz.d.pouring temperature parameter was 630 ℃. When the AISiTMg alloy slurry was prepared by low superheat pouring and weak electromagnetic stirring, the pouring temperature was 630℃. Increasing the stirring power appropriately could gain better spherical primary α-Al grains, but if the stirring power was increased to a certain value, the shape of the primary α-Al grains did not improve further. In this experiment, the optimiz.d.stirring power parameter was 0.36 kW.

关键词： Semi-solid AlSiTMg alloy Primary α-Al Pouring temperature Weak electromagnetic stirring

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MOdELING OF STRAIN-INdUCEd PRECIPITATION KINETICS IN Nb MICROALLOYEd STEELS

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Acta Metallurgica Sinica(English Letters) 2006年第5期19卷 385-390页

作者： X. G. z.ou z. Y. Liu d. Wu z. Li C.M. Li State Key Lab. of Rolling and Automation Northeastern University Shenyang 110004 China Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China Engineering ＆ Research Incorporation Limited WISDRI （Wuhan Iron ＆ Steel Design and

On the basis of the thermodynamic calculation of precipitation and considering the effect of strain on the precipitation behavior and chemical composition （Si and Mn）, the kinetics of precipitation from austenite has been investigated for different temperatures and strains. Nucleation theory and the solubility product of niobium, carbon, and nitrogen in austenite have been used to derive equations for the start time of precipitation as a function of temperature and composition. The value of n in Avrami equation was determined using the available experimental data from the published reports, which indicated that n is a constant independent of temperature and the end time of precipitation is a function of n and the start time of precipitation. The values of the start time and end time of precipitation predicted by the new model are compared with the experimental values and a good agreement was obtained between both.

关键词： strain-induced precipitation start time of precipitation end time ofprecipitation precipitation kinetics

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In Honor of the 80th Birthday of Professor WANG Fosong

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Science China Chemistry 2012年第5期55卷 643-645页

作者： Stephen z. d. Cheng the University of Akron

Professor Fosong Wang was born in Guangdong, China in 1933 and received his undergraduate education at Wuhan University between 1951 and 1955. Following graduation, he went to the Former Soviet Union to continue his graduate studies whereupon, in 1960, he received his Ph.d. in chemistry from the Institute of High Molecular Compounds of

关键词：生日化学研究所本科教育武汉大学松广东省研究生前苏联

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Synergetic deformation mechanisms in an Mg-z.-Y-z. alloy with intragranular LPSO structures

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Journal of Magnesium and Alloys 2023年第5期11卷 1754-1768页

作者： z.z.Peng X.H.Shao z.M.liang d.L.Wang L.W.Wang X.L.Ma Hebei Key Laboratory of Material Near-Net Forming Technology School of Materials Science and EngineeringHebei University of Science and TechnologyShijiazhuang 050018China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Whenua RoadShenyang 110016China

deformation kink is one of the important strengthening mechanisms of the long-period-stacking-ordered(LPSO)phase containing magnesium(Mg)alloys,while the deformation twin is generally *** optimiz. the mechanical properties of LPSO containing Mg alloy by simultaneously exciting kink and twin,we successfully prepared the Mg-z.-Y-z. alloy featuring intragranular LPSO phase and free grain boundary LPSO phase by *** unraveled the corresponding strengthening and toughening mechanisms through transmission electron microscopy characteriz.tion and theoretical *** high strength and good plasticity of the homogeniz.d.alloy benefit from the synergistic deformation mechanism of multiple kinking and twining in the *** the activation of kinking and twinning depends on the thicknesses of LPSO lamellae and their relative *** results may shed light on optimiz.ng the design of Mg alloys regulating the microstructure of LPSO phases.

关键词： Mg alloy LPSO distribution Kink Twin Transmission electron microscopy

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Finite element simulations on the mechanical properties of MHS materials

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Acta Mechanica Sinica 2007年第1期23卷 65-75页

作者： z. Y. Gao T. X. Yu d. Karagioz.va department of Mechanical Engineering Hong Kong University of Science &Technology Clear Water Bay Kowloon Hong Kong China Institute of Mechanics Bulgarian Academy of Sciences Acad. G. Bonchev Street Block 4 Sofia 1113 Bulgaria

Finite element simulations are carried out to examine the mechanical behavior of the metallic hollow sphere （MHS） material during their large plastic deformation and to estimate the energy absorbing capacity of these materials under uniaxial compression. A simplified model is proposed from experimental observations to describe the connection between the neighboring spheres, which greatly improves the computation efficiency. The effects of the governing physical and geometrical parameters are evaluated; whilst a special attention is paid to the plateau stress, which is directly related to the energy absorbing capacity. Finally, the empirical functions of the relative material density are proposed for the elastic modulus, yield strength and plateau stress for FCC packing arrangement of hollow spheres, showing a good agreement with the experimental results obtained in our previous study.

关键词： Cellular material Hollow sphere Large plastic deformation Numerical simulation FEM

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Erratum to “Plant defense against Necrotrophic Pathogens” [American Journal of Plant Sciences 11(12) (2020) 2122-2138]

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American Journal of Plant Sciences 2024年第2期15卷 122-138页

作者： Mahmoud H. Ghoz.an Nikita Gambhir Eman EL-Argawy Serkan Tokgöz.d.lip K. Lakshman Amitava Mitra University of Nebraska Lincoln NE USA USdA-ARS Beltsville MD USA

The original online version of this article (Ghoz.an, M.H., EL-Argawy, E., Tokgöz. S., Lakshman, d.K. and Mitra, A. (2020) Plant defense against Necrotrophic Pathogens. American Journal of Plant Sciences, 11, 2122-2138. https://***/10.4236/ajps.2020.1112149) was published mistakenly without another co-author, Nikita Gambhir. In this regard, we revise authors and “how to cite” sections by adding her name.

关键词： Effectors Host Immunity Signaling P/MAMP ETI disease Resistance

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MECHANICS OF RELAXING SiGe ISLANdS ON A VISCOUS GLASS

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Acta Mechanica Sinica 2002年第5期18卷 441-456页

作者： R. Huang H. Yin J. liang J. C. Sturm K. d. Hobart z. Suo Mechanical and Aerospace Engineering department and Princeton Materials Institute Princeton University Princeton USA department of Aerospace Engineering and Engineering Mechanics University of Texas at Austin Austin USA Center for Photonics and Optoelectronic Materials and department of Electrical Enineering Princeton University Princeton USA Naval Research Laboratory Washington DC USA

A process has been developed recently to fabricate a structure com- prising,from top to bottom,a SiGe thin film,a glass layer,and a Si *** SiGe film is a perfect crystal,and is under biaxial *** SiGe film is patterned into *** annealing,the glass flows and the islands *** resulting strain-free islands are used as substrates,to grow epitaxial optoelectronic *** article describes a series of studies on the annealing process,combining experiment and theory.A small island relaxes by expansion,starting at the edges and diffusing to the center.A large island wrinkles before the expansion reaches the *** some time,the wrinkles either disappear,or cause the island to fracture. We model the island as an elastic plate,and the glass layer as a viscous *** strains in the islands are measured by X-ray diffraction and Raman spectroscopy,and the wrinkle amplitudes by atomic force *** data are compared with the theoretical *** determine the conditions under which the islands relax by expansion without significant wrinkling,and demonstrate that a cap layer suppresses wrinkles,relaxing a large island crack-free.

关键词： semiconductor fabrication stress relaxation viscous flow elastic plate fracture

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Quasi-two dimensional Ruddlesden−Popper halide perovskites for laser applications

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Frontiers of physics 2024年第2期19卷 53-71页

作者： Kun Chen Qianpeng z.ang Yin liang Jiepeng Song Chun Li Shi Chen Fang Li Qing z.ang School of Mechanical and Electrical Engineering Wuhan Institute of TechnologyWuhan 430205China School of Materials Science and Engineering Peking UniversityBeijing 100871China Institute of Applied Physics and Materials Engineering Macao UniversityMacao 999078China

Quasi-two-dimensional(2d)Ruddlesden‒Popper(RP)halide perovskites,as a kind of emerged two-dimensional layered materials,have recently achieved great attentions in lasing materials field owing to their large exciton binding energy,high emission yield,large optical gain,and wide-range tuning of optical *** review will introduce research progresses of RP halide perovskites for lasing applications in aspects of materials,photophysics,and devices with emphasis on emission and lasing properties tailored by the molecular composition and *** materials,structures and fabrications are introduced in the first ***,the optical transitions and amplified spontaneous emission properties are discussed from the aspects of electronic structure,exciton,gain dynamics,and interface ***,the research progresses on lasing devices are summariz.d.and several types of lasers including VCSEL,dFB lasers,microlasers,random lasers,plasmonic lasers,and polariton lasers are *** last,the challenges and perspectives would be provided.

关键词： two-dimensional materials metal halide perovskite Ruddlesden−Popper halide perovskites lasing emission

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Warmer springs, laying date and clutch siz. of tree sparrows Passer montanus in Croatia

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Current z.ology 2011年第3期57卷 414-418页

作者： z. dOLENEC R dOLENEC A.R MdLLER department of z.ology Faculty of Science University of Zagreb Rooseveltov trg 6 HR- 10000 Zagreb Croatia High School Oroslavje Ljudevita Gaja 1 HR-49243 Oroslavje Croatia Laboratorie d'Ecologie Syst6matique et Evolution CNRS UMR 8079 Universit6 Paris-Sud 362 F-91405 Orsay Cedex France

Global surface air temperatures increased during the past 100 years. Many long-term studies of birds have reported a climatic influence on breeding performance. We analysed long-term changes in first laying date and clutch siz. for first clutches of sedentary, hole-nesting and socially monogamous tree sparrows Passer montanus during 1980-2009 in northwestern Croatia. Laying date advanced and spring temperature increased significantly during the study. date of laying was significantly correlated with mean air spring temperature and advanced by 8.6 days during the 30 years period. Laying date was delayed in extremely cold, but not in extremely warm springs compared to years with normal temperatures. These results suggest that current climate change including extreme change does not have negative effects on timing of laying or clutch siz.. In contrast to laying date, clutch siz. did not vary systematically during the study period or with mean spring air temperature changes [Current z.ology 57 （3）： 414-418, 2011].

关键词： Climate change Clutch siz. Laying date Passer montanus Tree sparrow

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INTERMETALLICS AS SUBSTITUTES FOR SUPERALLOYS

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 463-467页

作者： J. z.ang d. Feng z. Y. z.ong High Temperature Materials division Central Iron and Steel Research Institute Beijing 100081China

The application advances of TiAl, Ti3Al and Ni3Al base aUoys were denumstrated by Central Iron and Steel Research Institute, China. The recent research progresses on improving the reliability of cast TiAI were mainly presented and discussed. The characteristics of the self-oriented lamellar microstructure in cast TiAI were investigated in both as cast and as HlPed states. Based on the mechanical anisotropy of the cast lamellar microstructure, the component specific microstrueture design was proposed for a better performance and reliability of cast TiAl.

关键词： intermetallic application TiAl alloy microstructure design

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