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Journal of Iron and Steel Research International 2012年第7期19卷 71-78页

作者： I K lee C l Chung Y t.l.e Y t Chien Department of Materials Science and Engineering Da-Yeh University

During the first welding process in manufacturing a precise seam container, the steel material must first undergo a full annealing treatment. Mult.l.yer welding operations are conducted and then applied with refining treatment to obtain the goal by hardening. the influence of thermal refining on mechanical properties of annealed SAE 4130 by mult.l.yer GtAW （gas tungsten arc welding） was discussed. the AW （annealing＋welding） and AWSt （annealing＋welding＋solution＋tempering） occurred with a minimum hardness value at GGHAZ （grain growth heat affected zone） due to coarse grain growth~ the hardness occurred with sudden drops between the mult.l.yer welding, but was st.l. larger than the minimum value at HAZ （heat affected zone）. the welded joint efficiency of the AWSt was 89.9%, with the elongation reduced to 77.2% of ASt （annealing＋solution＋tempering）. the cross section of the tensile samples both appeared with a uniform dimple-shaped structure, and however the necking for ASt was greater than that for AWSt. the impact value for AWSt was 166.5% of ASt. Moreover, from microstructure observations, it was found that AWSt had a greater tendency to duct.l. failure than ASt. these results can be inferred., the process of steady pressure and the initial position of the precision tube breakage HAZ. However, when stress occurs instantly, HAZ can absorb more energy, therefore the initial damage does not occur.

关键词： thermal refining SAE 4130 mult.l.yer welding GtAW

Archaeological records of Dadiwan in the past 60 ka and the origin of millet agriculture

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Chinese Science Bulletin 2010年第16期55卷 1636-1642页

作者： ZHANG DongJu CHEN FaHu BEttINGER R l BARtON l JI DuXue MORGAN C wang Hui CHENG XiaoZhong DONG GuangHui GUIlDERSON t P ZHAO Hui Key laboratory of West China's Environment.l.System (MOE) Lanzhou University Lanzhou 730000 China Department of Anthropology University of California Davis CA 95616 USA Department of Sociology Social Work and Anthropology Utah State University Logan UT 84322 USA Gansu Province Institute of Cultural Relics and Archaeology Lanzhou 730000 China Preservation Institute ofDadiwan Qin'an 741600 China Center for Accelerator Mass Spectrometry Lawrence Liverrnore National Laboratory Livermore CA 94550 USA Key laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

this paper reports the recent excavation of Unit Dadiwan06 at the Dadiwan site in Qin’an County, Gansu.A 65 ka chronological framework is established for Dadiwan06 on the basis of absolute dating (AMS 14C and OSl), stratigraphy, climate change events and *** distributions reveal patterns of human behavioral variation and adaptation over the past 60 ka, from primitive hunting and gathering to advanced hunting and gathering, to primitive Neolithic agriculture, and finally to advanced Neolithic agriculture.

关键词：原始农业考古学大地新石器时代起源小米年代框架气候变化

Effect of NOx and SO2 on the photooxidation of methylglyoxal:Implications in secondary aerosol formation

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Journal of Environment.l.Sciences 2020年第6期32卷 151-162页

作者： Shuyan wang lin Du Narcisse t.tsona Xiaotong Jiang Bo You li Xu Zhaomin Yang Wenxing wang Environment Research Institute Shandong UniversityBinhai Road 72Qingdao266237China School of life Science Shandong UniversityBinhai Road 72Qingdao266237China

Methylglyoxal(CH3COCHO,MG),which is one of the most abundant α-dicarbonyl compounds in the atmosphere,has been reported as a major source of secondary organic aerosol(SOA).In this work,the reaction of MG with hydroxyl radicals was studied in a 500 l smog chamber at(293±3)K,atmospheric pressure,(18±2)%relative humidity,and under different NOx and *** size distribution was measured by using a scanning mobility particle sizer(SMPS)and the results showed that the addition of SO2 can promote SOA formation,while different NOx concentrations have different influences on SOA *** NOx suppressed the SOA formation,whereas the particle mass concentration,particle number concentration and particle geometric mean diameter increased with the increasing NOx concentration at.l.w NOx concentration in the presence of *** addition,the products of the OH-initiated oxidation of MG and the functional groups of the particle phase in the MG/OH/SO2 and MG/OH/NOx/SO2 reaction systems were detected by gas chromatography mass spectrometry(GC-MS)and attenuated tot.l.reflection fourier transformed infrared spectroscopy(AtR-FtIR)*** products,glyoxylic acid and oxalic acid,were detected by *** mechanism of the reaction of MG and OH radicals that follows two main pathways,H atom abstraction and hydration,is *** is provided for the formation of organic nitrates and organic sulfate in particle phase from IR *** of NOx and SO2 influence suggested that SOA formation from anthropogenic hydrocarbons may be more efficient in polluted environment.

关键词： Secondary organic aerosol Methylglyoxal OH-Initiated oxidation NOx SO2

StUDY ON HOt SAND COOlING EQUIPMENt WItH DAMPING SAND CASCADE AND VERtICAl SPOUtED-FlUIDIZED BED

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Acta Met.l.urgica Sinica(English letters) 2005年第5期18卷 669-673页

作者： l. C. wang F. wang X.H. You Department of Material Science and Engineering Taiyuan University of Science and Technology Taiyuan 030024 China

A new kind of hot sand cooling equipment with vertical spouted-fluidized bed is developed in this paper. It is similar to the traditional horizont.l.vibrating fluidized boiling cooler in principle but different from it in structure. the processing principle of the cooler is analyzed. the influence of main structural and processing parameters on the cooling effect and its mechanism are researched. Other characteristics of the cooler are discussed also. Experiment results show that the cooling efficiency η is equal to or larger than 83%, the temperature of output sand is less than 40℃ with the temperature of input sand is about between 80 and 90℃, and the productivity is 5t/ （h·m）

关键词： hot sand cooling fluidized bed foundry equipment

Improving Intergranular Stress Corrosion Cracking Resistance in a Fe–18Cr–17Mn–2Mo–0.85N Austenitic Stainless Steel through Grain Boundary Character Distribution Optimization

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Acta Met.l.urgica Sinica(English letters) 2022年第11期35卷 1849-1861页

作者： F.Shi l.Yan J.Hu l.F.wang t.Z.li W.li X.J.Guan C.M.liu X.W.li Department of Materials Physics and Chemistry School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China State Key laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Key laboratory for Anisotropy and texture of Materials(Ministry of Education) Northeastern UniversityShenyang 110819China

the grain boundary character distribution(GBCD) optimization and its effect on the intergranular stress corrosion cracking(IGSCC) resistance in a cold-rolled and subsequently annealed Fe-18 Cr-17 Mn-2 Mo-0.85 N high-nitrogen nickel-free austenitic stainless steel were systematically *** results show that stacking faults and planar slip bands appearing at the right amount of deformation(lower than 10%) are beneficial cold-rolled microstructures to the GBCD *** proportion of special boundaries gradually increases in the subsequent stages of recryst.l.ization and grain growth,accompanying with the growth of twin-related domain in the experiment.l.*** this way,the fraction of low ∑ coincidence site lattice(CSl) boundaries can reach as high as 82.85% for the specimen cold-rolled by 5% and then annealed at 1423 K for 72 *** GBCD optimization,low ∑ CSl boundaries and the special triple junctions(J2,J3) of high proportion can greatly hinder the nitride precipitation along grain boundaries and enhance the capability for intergranular crack arrest,thus improving the IGSCC resistance of the experiment.l.steel.

关键词： High-nitrogen austenitic stainless steel Grain boundary character distribution Coincidence site lattice(CSl)grain boundary Electron backscatter diff raction(EBSD) Intergranular stress corrosion cracking

Formation process and oxidation behavior of MCrAlY+AlSiY composite coatings on a Ni-based superalloy

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Journal of Materials Science & technology 2022年第25期120卷 65-77页

作者： S.M.li l.B.Fu W.l.Zhang W.li J.Sun t.G.wang S.M.Jiang J.Gong C.Sun School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Advanced Research Institute for Multidisciplinary Science Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China tianjin Key laboratory of High Speed Cutting and Precision Machining Tianjin University of Technology and EducationTianjin 300222China

An AlSiY coating and two MCrAlY+AlSiY composite coatings with different thickness of MCrAlY interlayer were prepared by arc ion plating(AIP)and vacuum *** isothermal oxidation behavior of coatings at 1100℃ for 300 h was also investigated to characterize the microstructure evolution of coatings during *** composite coatings exhibited a better high-temperature oxidation resistance at 1100℃ .the reason is that the addition of MCrAlY layer can greatly contribute to prevent the diffusion of refractory elements to the outer *** inhibition of Al inward diffusion can be much stronger,as the Si content increases in the outer layer during annealing.

关键词： Composite coating Annealing Arc ion plating SEM Oxidation

Oxidative damages to DNA by indoor PM10s: their relationships with trace element compositions

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Progress in Natural Science:Materials International 2005年第8期15卷 694-699页

作者： t. P. JONES,l. MEROllA School of Earth Ocean and Planetary Sciences Cardiff University Cardiff CF10 3YE UK School of Biosciences Cardiff University Cardiff CF10 3US UK

Plasmid DNA assay and ICP-MS analysis were conducted in order to investigate the bioreactivity of inhalable particles （PM_ 10） and the relationship between bioreactivity and trace element compositions of PM_ 10 in Beijing air. A tot.l.of four PM_ 10 samples were carefully selected to represent the indoor and corresponding outdoor environments: one from urban smoker's home, two from non-smoker's homes, and the other from the outdoor. In general, the oxidative damage by indoor PM_ 10 was slightly higher than that of outdoor. Among the four sets of samples, the PM_ 10 from the smoker's home had a lowest tD50 （toxic dose of PM_ 10 causing 50% DNA to be damaged）, being 100 μg·ml -1, suggesting the highest bioreactivity. the heavy met.l. are believed to be the main reason for oxidative damage to plasmid DNA. the ICP-MS analysis combined with the DNA assay showed that the water-soluble zinc levels had better relationship with tD50 values than other elements, implying that water-soluble zinc might play an important role in the damage of DNA. It is concluded that the PM_ 10 in smoker's home had the highest.l.vel of water-soluble zinc as well as the lowest tD50 （highest bioreactivity）. Iron is considered to be one of the most bioreactive elements, but it will cause lit.l. damage to plasmid DNA, probably because iron is mainly in water-insoluble state in Beijing PM_ 10.

关键词： plasmid DNA assay oxidative capacity trace element indoor air PM_ 10.

Influence of austenization temperature on the erosion behavior of austempered duct.l. irons

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Journal of University of Science and technology Beijing 2008年第1期15卷 29-33页

作者： l.C. Chang l C. Hsui l.H. Chen S.t. lui Department of Mechanical Engineering Technology and Science Institute of Northern Taiwan Taipei 112 China Talpei Department of Materials Science and Engineering Cheng-Kung University Talnan 800 China Taipei

the erosion behavior of austempered duct.l. irons austenized at different temperatures was studied. the results indicate that the erosion rate well correlates with the mechanical properties. At high impact angles, increasing duct.l.ty and mechanical energy density results in decreasing erosion rate, whereas increasing hardness reduces the erosion rate at.l.w impact angles. 2008 University of Science and technology Beijing. All rights reserved.

关键词： austempered duct.l. iron erosion mechanical properties austenization

Global evolution of Equidae and Gomphotheriidae from South America

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Integrative Zoology 2014年第4期9卷 434-443页

作者： Josél.PRADO María t.AlBERDI INCUAPA CONICET-UNICENNational University of Central Buenos Aires ProvinceOlavarríaArgentina Department of Paleobiology Museo Nacional de Ciencias NaturalesCSICMadridSpain

the contemporary South American mammalian communities were determined by the emergence of the Isthmus of Panama and by the profound climatic oscillations during the *** and gomphotheres were 2 very conspicuous groups of immigrant mammals from North America that arrived in South America during the *** present study compiles updated data on the phylogeny,systematics and ecology of both groups in South *** horses in South America are represented by 2 genera,Hippidion and Equus,as are the gomphotheres,represented by Cuvieronius and *** genera of horses include small(Hippidion devillei,***,*** and ***)and large forms(Equus neogeus and ***),which dispersed into South America using 2 different *** possible model for this dispersion indicates that the small forms used the Andes corridor,while larger horses dispersed through the eastern route and through some coast.l.*** the case of gomphotheres,Cuvieronius and Stegomastodon reached South America in 2 independent dispersal events,and Cuvieronius dispersed across the Andean corridor,while large Stegomastodon spread along the eastern *** and gomphotheres present values ofδ^(13)C from woodlands to C4 grass*** present.l.wer values ofδ^(13)C than Equus in the late Pleistocene,whereas the gomphotheres diverge from value ofδ^(18)O,reflecting that Cuvieronius inhabited the Andean corridor and Stegomastodon dispersed through eastern *** gomphothere and horse species recorded in South America became extinct around the time that humans arrived.

关键词： Equidae Gomphotheriidae Plio-Pleistocene South America