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Journal of Iron and Steel Research International 2016年第4期23卷 401-408页

作者： Wu-hua YUAN Xue-hui GONG Yong-qing SUN Jian-xiong LIANG College of Materials Science and Engineering Hunan University Special Steel institute Central Iron and Steel Research Institute

The microstructure, morphology of precipitates and retained austenite and the volume fraction of retained austenite in 0crl6Ni5Mo stainless steel during the tempering process were analyzed using optical microscope （OM）, transmission electron microscope （TEM）, X-ray diffraction （XRD） and scanning transmission electron microscope （STEM）. The results show that the microstructure of the tempered steel is mainly composed of tempered martensite, retained austenite, and delta ferrite. In the case of samples tempered from 500 to 700℃, the precipitates are mainly M23C6, which precipitate along the lath martensite boundaries. The precipitate content increases with the tempering temperature. During the tempering process, the content of retained austenite initially increases and then decreases, the maximum content of retained austenite being 29 vol.% upon tempering at 600℃. TEM analysis of the tested steel reveals two morphology types of retained austenite. One is thin film-like retained austenite that exists along the martensite lath boundary. The other is blocky austenite located on packet at the boundary and the original austenite grain boundary. To further understand the stability of reversed austenite, the Ni content in reversed austenite was measured using STEM. Results show a significant difference in nickel concentrations between reversed austenite and martensite.

关键词： 0cr16Ni5Mo stainless steel microstructure evolution precipitate reversed austenite thermal stability

Effect of Fe addition on microstructure and mechanical properties of Ti-25V-15cr-2Al-0.2C alloy

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中国有色金属学会会刊：英文版 2003年第6期13卷 1329-1332页

作者：雷力明黄旭孙福生吴学仁曹春晓 Beijing institute of Aeronautical Materials

The effect of 2% Fe addition on the microstructure and mechanical properties of Ti-25V-15cr-2Al-0.2C alloy(mass fraction) was studied. It is found that the addition of 2% Fe seems to have no obvious effect on the microstructure of the alloy, but results in a significant change in mechanical properties. Compared with the alloy without Fe addition, the alloy with 2% Fe addition exhibits remarkable higher tensile strength and creep resistance, whereas the ductility is relatively lower at room temperature. The significant changes in mechanical properties can be rationalized by the decrease of stacking fault energy caused by the addition of 2% Fe.

关键词：钛合金铁显微结构机械性能

Precipitated phases of superaustenitic stainless steel 654SMO

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Journal of Iron and Steel Research International 2017年第7期24卷 743-749页

作者： Zhi-gang Song En-xiang Pu Special Steel institute Central Iron & Steel Research Institute School of Materials Science and Engineering Tsinghua University

The phase diagram of superaustenitic stainless steel 654SMO was calculated by thermodynamic software and the precipitated phases in the specimens aged at 800-1100°C for 1hwere studied by methods of physicochemical phase analysis,scanning electron microscopy and transmission electron *** results showed that the size of precipitated particles increased with increasing the *** amount of second phases reached the maximum value at 900°C,but decreased above 900°*** were about eight kinds of precipitated phases in 654SMO includingσphase,cr_2N,μphase,χphase,Laves phase,M_（23）C_6,M_6C and M_3C,in which theσphase and cr_2N were the dominant precipitated phases.

关键词： 654SMO Precipitation Superaustenitic stainless steel Precipitated phase Second phase

Development and Characterization of Elite Doubled Haploid Lines from Two Indica Rice Hybrids

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Rice science 2015年第6期22卷 290-299页

作者： Rukmini MISHRA Gundimeda Jwala Narashima RAO Ravi Nageswara RAO Pankaj KAUSHAL crop Improvement Division Central Rice Research Institute Indian Grassland and Fodder institute

Despite significant yield advantage over inbred rice, the adoption rate of hybrid rice in India is very low due to the high seed cost and poor quality of the produce. To alleviate the problem, we initiated a doubled haploid （DH） breeding approach to develop new lines from two elite indica rice hybrids （crHR5 and crHR7） through rapid fixation of homozygosity in the recombinants. In vitro culture of the rice anthers resulted in 243 and 186 fertile DH lines of crHR5 and crHR7, respectively. Flow cytometric and pollen fertility analyses confirmed the DH ploidy status of the regenerations. Morpho-agronomic evaluation revealed 100% uniformity and stability for all the characters in the DH lines of both hybrids. Nineteen promising DH lines of each hybrid were advanced to A2 generation for yield evaluation. The yield levels of the DH lines ranged from 5 097-6 965 kg/hm^2 for crHR5 and 5 141-7 235 kg/hm^2 for crHR7, which were at par or higher than the parental hybrids. Physico-chemical characterization and cooking quality analyses revealed significant and acceptable values for grain length and width, alkali spreading value, amylose content and water uptake ratio of the selected DH lines. Three DH lines, cr5-10, cr5-49, cr5-61 from crHR5, and four DH lines, cr7-5, cr7-7, cr7-12 and cr7-52 from crHR7, showed significant grain yield and quality characteristics and have been recommended for multi-location trials for subsequent release as new indica doubled haploid rice varieties.

关键词： anther culture doubled haploid indica rice hybrid

Executionary pathway for apoptosis: lessons from mutant mice

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Cell Research 2000年第4期10卷 267-278页

作者： WOO MINNA RAZQALLAH HAKEM TAK W. MAK Amgen institute and Ontario Cancer institute, Departments of Immunology and Medical Biophysics, University of Toronto, Canada 1Amgen institute and Ontario Cancer institute Departments of Immunology and Medical Biophysics University of Toronto Canada 1Amgen institute and Ontario Cancer institute Departments of Immunology and Medical Biophysics University of Toronto Canada 1Amgen institute and Ontario Cancer institute Departments of Immunology and Medical Biophysics University of Toronto Canada

Apoptosis or programmed cell death (PCD) is an evolutionarily conserved cellular process that is essential for normal development and homeostasis of multicellular organisms. Defects in the apoptosis signaling result in many diseases including autoimmune diseases and cancer. The apoptosis signaling pathway was first described genetically in the nematode Caenorhabditis elegans which serves as a framework for the more complex apoptotic pathways that exist in mammals. In this review, we will discuss the apoptotic pathways that are emerging in mammals as elucidated by studies of gene-targeted mutant mice.

关键词： Apoptosis progammed cell death caspases death receptors mitochondri?

Quantitative mineralogical characterization of chrome ore beneficiation plant tailing and its beneficiated products

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International Journal of Minerals,Metallurgy and Materials 2015年第4期22卷 335-345页

作者： S.K.Das CSIR-institute of Minerals and Materials Technology

Mineralogical characterization and liberation of valuable minerals are primary concerns in rnineml processing industries. The pre- sent investigation focuses on quantitative mineralogy, elemental deportment, and locking-liberation characteristics of the beneficiation of tailings from a chrome ore beneficiation plant in the Sukinda region, Odisha; methods used for the study of the beneficiated tailings are QEMSCAN~, X-ray diffraction （XRD）, and mineral chemistry by a scanning electron microscope equipped with an energy-dispersive spec- trometer （SEM-EDS）. The tailing sample was fine grained （69.48wt% below 45 μm size）, containing 20.25wt% cr203 and 39.19wt% Fe203, with a cr：Fe mass ratio of 0.51. Mineralogical investigations using QEMSCAN studies revealed that chromite, goethite, and gibbsite are the dominant mineral phases with minor amounts of hematite, kaolinite, and quartz. The sample contained 34.22wt% chromite, and chromite liberation is more than 80% for grains smaller than 250 ~tm in size. Based on these results, it was predicted that liberated chromite and high-grade middling chromite particles could be separated from the gangue by various concentration techniques. The tailing sample was beneficiated by hydrocyclone, tabling, wet high-intensity magnetic separation （WHIMS）, and flotation in order to recover the chromite. A chromite concentrate with 45.29wt% cr203 and a cr：Fe mass ratio of 1.85 can be produced from these low-grade chromite ore beneficiation plant rejects.

关键词： tailings mineralogy chromites beneficiation

Effect of carbide formers on microstructure and thermal conductivity of diamond-Cu composites for heat sink materials

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中国有色金属学会会刊：英文版 2009年第5期19卷 1161-1166页

作者：夏扬宋月清林晨光崔舜方针正 General Research institute for Nonferrous Metals

Diamond-copper composites were prepared by powder metallurgy,in which the diamond particles were pre-coated by magnetic sputtering with copper alloy containing a small amount of carbide forming elements(including B,cr,Ti,and Si).The influence of the carbide forming element additives on the microstructure and thermal conductivity of diamond composites was *** is found that the composites fabricated with Cu-0.5B coated diamond particles has a relatively higher density and its thermal conductivity approaches 300 W/(m·K).Addition of 0.5%B improves the interfacial bonding and decreases thermal boundary resistance between diamond and Cu,while addition of 1%cr makes the interfacial layer break away from diamond *** actual interfacial thermal conductivity of the composites with Cu-0.5B alloy coated on diamond is much higher than that of the Cu-1cr layer,which suggests that the intrinsic thermal conductivity of the interfacial layer is an important factor for improving the thermal conductivity of the diamond composites.

关键词：铜复合材料硬质合金导热系数钻石显微结构散热片金刚石复合材料金刚石颗粒

Triggers and sources of volatile-bearing plumes in the mantle transition zone

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Geoscience Frontiers 2015年第5期6卷 679-685页

作者： Inna Safonova Konstantin Litasov Shigenori Maruyama V.S.Sobolev institute of Geology and Mineralogy SB RAS Novosibirsk State University Earth-Life Science institute Tokyo Institute of Technology

The paper discusses generation of volatile-bearing plumes in the mantle transition zone(MTZ) in terms of mineral-fluid petrology and their related formation of numerous localities of intra-plate bimodal volcanic series in Central and East *** plume generation in the MTZ can be triggered by the tectonic erosion of continental crust at Pacific-type convergent margins and by the presence of water and carbon dioxide in the *** probable sources of volatiles are the hyclrated/carbonated sediments and basalts and serpentinite of oceanic slabs,which can be subducted down to the deep *** erosion of continental crust supplies crustal material enriched in uranium and thorium into the mantle,which can serve source of heat in the *** heating in the MTZ induces melting of subducted slabs and continental crust and mantle upwelling,to produce OIB-type mafic and felsic melts,respectively.

关键词： Asis Pacific-type convergent margin Continental cr

Distinct metamorphic evolution of alternating silica-saturated and silica-deficient microdomains within garnet in ultrahigh-temperature granulites: An example from Sri Lanka

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Geoscience Frontiers 2017年第5期8卷 1115-1133页

作者： P.L.Dharmapriya Sanjeewa P.K.Malaviarachchi Leo M.Kriegsman K.Sajeev Andrea Galli Y.Osanai N.D.Subasinghe C.B.Dissanayake Postgraduate institute of Science University of Peradeniya 20400 Sri Lanka Department of Geology Faculty of Science University of Peradeniya 20400 Sri Lanka Department of Geology Naturalis Biodiversity Center Darwinweg 2 2333 CR Leiden The Netherlands Department of Earth Sciences University of Utrecht NL-3584 CD Utrecht The Netherlands Center for Earth Sciences Indian Institute of Science Bangalore 560012 India Department of Earth Sciences ETH Zurich Sonnegstrasse 5 CH-8092 Zurich Switzerland Division of Earth Sciences Department of Environmental Changes Faculty of Social and Cultural Studies Kyushu University 744 Motooka Fukuoka 819-0395 Japan National institute of Fundamental Studies Hantana Road Kandy Sri Lanka

Here we report the occurrence of garnet porphyroblasts that have overgrown alternating silica-saturated and silica deficient microdomains via different mineral reactions. The samples were collected from ultrahigh-temperature(UHT) metapelites in the Highland Complex, Sri Lanka. In some of the metapelites, garnet crystals have cores formed via a dehydration reaction, which had taken place at silicasaturated microdomains and mantle to rim areas formed via a dehydration reaction at silica-deficient microdomains. In contrast, some other garnets in the same rock cores had formed via a dehydration reaction which occurred at silica-deficient microdomains while mantle to rim areas formed via a dehydration reaction at silica-saturated microdomains. Based on the textural observations, we conclude that the studied garnets have grown across different effective bulk compositional microdomains during the prograde evolution. These microdomains could represent heterogeneous compositional layers(paleobedding/laminations) in the precursor sediments or differentiated crenulation cleavages that existed during prograde metamorphism. UHT metamorphism associated with strong ductile deformation, metamorphic differentiation and crystallization of locally produced melt may have obliterated the evidence for such microdomains in the matrix. The lack of significant compositional zoning in garnet probably due to self-diffusion during UHT metamorphism had left mineral inclusions as the sole evidence for earlier microdomains with contrasting chemistry.

关键词： UHT Metapelites Garnet Microdomains Highland Complex Sri Lanka

Theoretical Exploration of Alloying Effects on Stabilities and Mechanical Properties ofγʹPhase in Novel Co–Al–Nb-Base Superalloys

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1238-1248页

作者： Guan-Cheng Gu Zhao-Jing Han Ze-Yu Chen Zhao-Xuan Li Sheng-Bao Xia Zheng-Ning Li Hua Jin Wei-Wei Xu Xing-Jun Liu Shenzhen Research institute of Xiamen University School of Aerospace EngineeringXiamen UniversityXiamen361005China institute of Materials Genome and Big Data Harbin Institute of TechnologyShenzhen518055China

The new developedγ/γʹCo–Al–Nb-base alloys show great potentials as high-temperature ***,finding appropriate compositions to improve performance of alloys still poses a great challenge to the development of Co–Al–Nb-base *** by the lack of alloying effects on fundamental properties of criticalγʹphase,we systematically performed a theoretical investigation on the effect of alloying elements TM(TM:Ti,V,cr,Zr,Mo,Ta,W,Re,and Ru)on phase stabilities and mechanical properties of L1_(2)-typeγʹ(Co,Ni)_(3)(Al,Nb).By analyzing the stability ofγʹphase with respect to its competitive B2 and D0_(19) phases,the results shown that Ti,V,and cr enhance the L1_(2) stability and widen the L1_(2)–D0_(19) energy barrier,in which V yields the maximum *** analysis of electronic structure indicated that the alternation of valence electrons at fermi level would be the atomic origin for doping TM inγʹ*** calculated results of mechanical properties shown that V and cr are expected to be optimal dopant for enhancing the strength and the ductility ofγʹ*** addition of Ta is also beneficial for enhancing the strength at the slight expense of ductility ofγʹ*** drawing the mechanical maps,the preferred composition range for the phases with desired properties is roughly demarcated in theory for the multi-addition of V/cr and V/Ta inγʹ*** findings would be useful for optimizing the performance of novelγ/γʹCo–Al–Nb-base superalloys.

关键词： Co-Al-Nb-base superalloys γ/γʹdual-phase Phase stability Mechanical properties First-principle methods