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Creep Induced Phase Transformation in extruded Zn-Al Alloy

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journal of Materials Science & Technology 1997年第6期13卷 503-507页

作者： Y.H.ZHU and j.juarez Islas(Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico, Apartado P.70-360,Mexico D.F.04510, Mexico)e. Orozco(Instituto de Fisica, Universidad Autonoma de Mexico, Apartado P.20-364, Mexico D.F.04510, Instituto de Investigaciones en Materiales Universidad Nacional Autonoma de Mexico Apartado P. 70-360 Mexico D. F. 04510 Mexico Instituto de Fisica Universidad Autonoma de Mexico Apartado P. 20-364 Mexico D. F. 04510 Mexico

Phase transformation and microstructural change of an extruded eutectoid Zn-Al alloy Zn76Al22Cu2 (wt pct) were investigated during creep testing by using SeM and X-ray diffraction techniques. Creep induced decomposition of a metastable η'T phase and a four phase transformation, α+ ε →T' +η, occurred during the creep testing. Also a microstructural change was observed from a lamellar structure into a spheroidized structure in the rupture part of the extruded alloy. It provided evidence of creep induced phase transformations which occurred in ageing process. The mechanism of creep rupture of the extruded Zn-Al alloy was also discussed.

关键词： Al Zn Creep Induced Phase Transformation in extruded Zn-Al Alloy

Paleobiological significance of the james Ross Basin

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Advances in Polar Science 2019年第3期30卷 186-198页

作者： j.Alistair CRAMe British Antarctic Survey High CrossMadingley RoadCambridge CB3 0ETUK

The extensive Late Mesozoic–early Cenozoic sedimentary succession exposed within the james Ross Basin,Antarctica has huge potential to enhance paleobiological investigations into both the marine and terrestrial fossil *** excess of 7 km in total thickness and spanning the early Cretaceous(Aptian)–Late eocene in age,it represents an invaluable high-latitude(~65°S)site for comparison with lower latitude,tropical ones in an essentially greenhouse *** early Cretaceous(Aptian–Albian)sequence is deep-water but there are indications of shallowing to inner shelf depths in both the Turonian and Coniacian *** first prolific shallow-water marine fauna occurs in the Santonian–Campanian Santa Marta Formation and this is followed by repeated occurrences through the later Campanian,Maastrichtian,Danian and Middle eocene(Lutetian).In this study an attempt has been made to compare these Antarctic faunas directly with the well-known ones of the same age from the US Gulf *** comparisons made for three time slices,Late Maastrichtian,Danian and Middle eocene,indicate that the Antarctic is characterised by both low taxonomic diversity and high levels of *** james Ross Basin is providing important evidence to indicate that the highest southern latitudes have always been characterised by a distinctive temperate biota,even on a pre-glacial *** roots of at least some elements of the modern Southern Ocean biota can be traced back to a Late Mesozoic–early Cenozoic austral realm.

关键词： james Ross Basin biostratigraphy molluscan faunas US Gulf Coast biodiversity patterns evolutionof temperate biotas

INVeSTIGATION OF SURFACe MORPHOLOGY, STRUCTURe AND eLeCTROCATALYTIC PROPeRTIeS FOR O_2 eVOLUTION OF TITANIUM BASeD IrO_2+Ta_2O_5 COATINGS

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Acta Metallurgica Sinica(english Letters) 2000年第3期13卷 849-856页

作者： j.M Hu j.X. Wu H.M Meng YR. Zhu D.B. Sun and D.j. Yang(Be.j.ng Corrosion and Protection Center, Open Laboratory of Corrosion, erosion and Surface Technology,University of Science and Technology Be.j.ng, Be.j.ng 100083, China) Univ of Science and Technology Beijing Beijing China

Titanium based IrO2 +Ta2O5 oxide anodes with different compositions and pyrolysis temperatures were prepared by termodecompoisition method. By using X-ray diffraction (XRD), the structure and texture coefficient of the coatings, TC(hkl), of IrO2 rutile crystal have been tested. It showed that, the crystallization processes of IrO2 and Ta2O5 in xIrO2 +(100-x) Ta2 O5 (x is in mol%) films affected and confined each *** the mixed system, IrO2 rutile phase existed as a solid solution with Ta, and attained the maximum solubility when x=70mol%, i.e. for the coating of 70% IrO2 +*** the coatings of low iridium content or at low preparing tem pemture, (110) and (101) pwtered orientations were dominant. However, preferred growth of IrO2 weakened with increasing either iridium content or temperature. Three typical surface morphologies were observed by using scanning electron tnicroscopy(SeM). The crystallite size of the mixed oxide coatings were finest for the the film of 70%IrO2 +30%Ta2O5,and decreased with the pyrolysis tempemture. As the results of the finest crystallite segregating on sudece and the maxitnum solid solubility of Ir and Ta component in deposits, the coatings with the composition of 70%IrO2 +Ta2O5 prepared at 450℃ presented the mdrimutn electrocatalgtic activitg for O2 evolution in 0. 5M H2SO4 *** to 550℃, Ti base suffered to oxidation resulting in decreasing anode conductivity,therefore, coatings performed a low activity.

关键词： titanium based coating anode iridium oxide tantalum oxide,solid solution crystallite orientation electrocatalytic activity

Health,the basics/ 3rd ed.

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1999年

作者： Donatelle Rebecca j.

来源：畅想之星图书光盘版（南... 评论

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为害芸苔属作物的鳞翅目害虫幼虫检索表

植物检疫 1982年第3期 57-58页

作者： e.j.emmett 王洪茂

在检索表适用于二令以上的幼虫,体长系指各种老熟幼虫的最大长度的平均值。1(20) 幼虫有腹足五对。2(7) 头部有黑色和白色的毛。头部黑,黑灰或绿色。3(4) 体色淡黄褐色,有黑色斑纹和黄色纵条斑。头部初全为黑色,最后一令为黑灰色,额黄色... 详细信息

在检索表适用于二令以上的幼虫,体长系指各种老熟幼虫的最大长度的平均值。1(20) 幼虫有腹足五对。2(7) 头部有黑色和白色的毛。头部黑,黑灰或绿色。3(4) 体色淡黄褐色,有黑色斑纹和黄色纵条斑。头部初全为黑色,最后一令为黑灰色,额黄色,体长40mm。……大菜粉蝶(Pieris brassicae L.)4(3) 头与体绿色,体表密生黑色和白色毛片(斑),其上着生短毛。气门线在气门及

关键词：体长斑纹暗色腹足附肢气门线幼虫检索表

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固体气泡损伤探测器记录高能重离子的特性

原子能科学技术 2000年第Z1期34卷 30-33页

作者：郭士伦李丽 T.Doke.j.Kikuchi A.Kyan e.Yoshihira T.Kato T.Murakami 中国原子能科学研究院核物理研究所北京102413 AdvancedResearchInstituteforScienceandengineering WasedaUniversity

利用自行研制的大型固体气泡损伤探测器和日本国立辐射科学研究所医用重离子加速器(HIMAC)提供的高能重离子束对固体气泡损伤探测器探测高能重离子的特性进行了研究。研究说明 :1)固体气泡损伤探测器是一种新型重离子阈探测器 ,阈值可... 详细信息

利用自行研制的大型固体气泡损伤探测器和日本国立辐射科学研究所医用重离子加速器(HIMAC)提供的高能重离子束对固体气泡损伤探测器探测高能重离子的特性进行了研究。研究说明 :1)固体气泡损伤探测器是一种新型重离子阈探测器 ,阈值可用临界能量损失率表征 ;2 )最大径迹长度与重离子的原子序数有关 ,利用这种关系可鉴别重离子的原子序数 ;3)在重离子径迹的一定范围内 ,气泡线密度与重离子的能量损失率de/dX有关 ,测定该范围内两点的气泡线密度和其间的射程可求得重离子的原子序数和能量。

关键词：固体气泡损伤探测器高能重离子鉴别径迹探测器

New para-magnetic(CoFeNi)(50)(CrMo)(50-x)(CB)x(x=20,25,30)non-equiatomic high entropy metallic glasses with wide supercooled liquid region and excellent mechanical properties

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journal of Materials Science & Technology 2020年第8期36卷 135-143页

作者： jeong Tae Kim Sung Hwan Hong jin Man Park jürgen eckert Ki Buem Kim erich Schmid Institute of Materials Science Austrian Academy of Sciences(ÖAW)Jahnstrae 128700LeobenAustria Hybrid Materials Center(HMC) Department of Nanotechnology and Advanced Materials EngineeringSejong University209Neungdong-roGwangjin-guSeoul143-747Republic of Korea Global Technology Center(GTC) Samsung Electronics Co.Ltd129 Samsung-roYeongtong-guSuwonsiGyeonggi-do443-742Republic of Korea Department of Materials Science Chair of Materials PhysicsMontanuniversität LeobenJahnstraße 128700LeobenAustria

In this study,high entropy metallic glasses(HeMGs)were developed through a combination of concepts for designing metallic glasses(main element+transition metal+metalloid element)and high-entropy alloys(more than five elements,each element having an atomic concentration between 5 at.%and 35 at.%).The developed metallic glass alloys are composed of Co-Fe-Ni main elements,transition metals(Cr,Mo)and metalloid elements(C,B).Moreover,the present work reports the thermal,mechanical and magnetic properties of(CoFeNi)(50)(CrMo)(50-x)(CB)x alloys with x=20,25,*** developed as-spun HeMGs exhibit typical paramagnetic properties even for a high amount of ferromagnetic elements(Co,Fe,and Ni)and have high elastic modulus(103–160 GPa)and hardness(14–27 GPa),thus possessing mechanical properties similar to well-known Co-based metallic glasses(Co-Cr-Mo-C-B system).In addition,some of the bulk samples prepared with a diameter of 2 mm form bulk metallic glasses with a high compressive strength around 3.5 *** mechanisms determining the stability of the supercooled liquid,as well as the paramagnetic and mechanical properties for the developed non-equiatomic HeMGs,are discussed.

关键词： Metallic glasses Paramagnetism High entropy alloys Phase stability