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青藏高原及其周边寒武纪综合地层、生物群与古地理演化

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中国科学：地球科学 2024年第4期54卷 968-991页

作者：孙智新孙郎赵方臣潘兵 Malik Muhammad Saud Sajid KHAN Shehryar AHMED 杨传苗兰云殷宗军李国祥朱茂炎中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室南京210008 中国科学院大学地球与行星科学学院北京100049

青藏高原及其周边地区具有漫长且复杂的构造演化历史.印度北部、拉萨、羌塘、柴达木、中祁连等大小不同的克拉通和地块,以及位于它们之间的造山带构成了青藏高原的主体.寒武纪时期,这些克拉通和地块大多位于冈瓦纳大陆的西北缘,并以发... 详细信息

青藏高原及其周边地区具有漫长且复杂的构造演化历史.印度北部、拉萨、羌塘、柴达木、中祁连等大小不同的克拉通和地块,以及位于它们之间的造山带构成了青藏高原的主体.寒武纪时期,这些克拉通和地块大多位于冈瓦纳大陆的西北缘,并以发育与原特提斯洋有关的复杂岩浆-构造运动而与周边的阿拉伯、中伊朗、阿富汗、塔里木、阿拉善、华北、华南和滇缅马等构造单元相关联.从地层记录上看,这一时期区域内的大部分稳定陆块上发育了由陆源碎屑岩和碳酸盐岩组成的浅水陆棚沉积,其中包含面貌相近的典型浅水相三叶虫组合.而在原特提斯洋中的祁连构造带,寒武系则是一套在大洋扩张环境下形成的、以中基性火山岩和硅质岩为主的复杂地层序列,其中包含的碳酸盐岩含有斜坡相三叶虫组合.本文在广泛文献调研的基础上,结合第二次青藏高原综合科学考察中的野外观察及新获得的化石证据,对青藏高原及其周边地区不同构造单元上寒武纪地层发育的总体特征进行了概述.在此基础上,利用可获得的生物地层学和同位素年代学等资料,总结了不同构造单元上寒武纪地层的划分和年代地层对比,编制了岩石和生物地层的综合对比表.此外,从生物古地理的角度,简要讨论了寒武纪研究区内主要构造单元的古地理相关性,以及与原特提斯构造带演变有关的问题.

关键词：青藏高原寒武系地层古地理生物群冈瓦纳大陆原特提斯洋

Review of remote sensing and geospatial technologies in estimating rooftop rainwater harvesting (RRWH) quality

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International Soil and Water Conservation Research 2019年第3期7卷 266-274页

作者： Masayu Norman Helmi z.M.Shafri Shattri b.Mansor badronnisa Yusuf Department of Civil Engineering Faculty of EngineeringUniversiti Putra Malaysia(UPM)43400 SerdangSelangorMalaysia Geospatial Information Science Research Centre(GISRC) Faculty of EngineeringUniversiti Putra Malaysia(UPM)43400 SerdangSelangorMalaysia Centre of Studies for Surveying Science&Geomatics Faculty of ArchitecturePlanning&SurveyingUniversiti Teknologi MARA(Perlis)02600 ArauPerlisMalaysia

Rooftop rainwater harvesting (RRWH) systems can provide low-cost decentralized water to urban and rural households that have no access to treated *** systems are considered the key strategic adoption measures for communities affected by climate *** materials,roofing conditions,roofing geometry,weather conditions,and land use/land cover (LULC) conditions can significantly affect the quality of ***,the effects of these factors on RRWH quality must be analyzed *** sensing and Geographical Information System (GIS) have been widely used in urban environmental ***,these technologies have never been used to analyze,map,and model the effect of various factors on RRWH *** review determines the research gaps in the use of geospatial technologies in estimating RRWH quality and simulate the implications of roofing materials and roofing surface conditions towards the urban *** approach for the integrated use of remote sensing and GIS to assess the quality of RRWH is also proposed.

关键词： Roofing materials Roofing conditions Spatial modeling Environmental impact Remote sensing GIS

Correlation between depassivation and repassivation processes determined by single particle impingement:Its crucial role in the phenomenon of critical flow velocity for erosion-corrosion

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Journal of Materials Science & Technology 2021年第30期89卷 158-166页

作者： L.L.Li z.b.Wang S.Y.He Y.G.zheng CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Department of Physics Southern University of Science and TechnologyGuangdong 518055China

The correlation between depassivation and repassivation processes,which is significant in erosioncorrosion,was quantitatively investigated by single particle impingement tests at various flow velocities and impact *** results show that both repassivation and depassivation processes are associated with the kinetic energy of solid particle,and demonstrate that the repassivation is retarded by *** phenomenon probably results from the depassivation-induced microstructure *** this basis,the dependence of critical flow velocity(CFV)for erosion-corrosion on the solid particle concentration and diameter is further theoretically predicted and experimentally ***,the crucial role of depassivation-repassivation in CFV phenomenon is further highlighted.

关键词： Erosion-corrosion Stainless steel Depassivation-repassivation Single particle impact Passive film

Influence of Al_2O_3 particle pinning on thermal stability of nanocrystalline Fe

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Journal of Materials Science & Technology 2018年第4期34卷 599-604页

作者： G.b.Shan Y.z.Chen M.M.Gong H.Dong b.Li F.Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Second-phase particle pinning has been well known as a mechanism impeding grain boundary （Gb） migration, and thus, is documented as an efficient approach for stabilizing nanocrystalline （NC） materials at elevated temperatures. The pinning force exerted by interaction between small dispersed particles and Gbs strongly depends on size and volume fraction of the particles. Since metallic oxides, e.g. Al2O3, exhibit great structural stability and high resistance against coarsening at high temperatures, they are expected as effective stabilizers for NC materials. In this work, NC composites consisting of NC Fe and Al2O3 nanoparticIes with different amounts and sizes were prepared by high energy ball milling and annealed at various temperatures （Tann） for different time periods （tann）. Microstructures of the ball milled and annealed samples were examined by X-ray diffraction and transmission electron microscopy. The results show that the addition of Al2O3 nanoparticles not only enhances the thermal stability of NC Fe grains but also reduces their coarsening rate at elevated temperatures, and reducing the particle size and/or increasing its amount enhance the stabilizing effect of the Al2O3 particles on the NC Fe grains.

关键词： Iron Nanocrystalline materials ball milling zener pinning Grain growth Thermal stability

Superb Strengthening Effect of Net-Like Distributed Amorphous Al_(2)O_(3)on Creep Resistance of(b_(4)C+Al_(2)O_(3))/Al Neutron-Absorbing Materials

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Acta Metallurgica Sinica(English Letters) 2022年第12期35卷 2007-2013页

作者： Y.N.zan X.Lei J.F.zhang D.Wang Q.z.Wang b.L.Xiao z.Y.Ma Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.LtdBejing 100840China

b4C reinforced Al composites are widely used as neutron absorbing materials(NAMs)due to excellent neutron absorbing efficiency,however,such NAMs exhibit poor high-temperature *** meet the requirement for structure-function integration,NAMs with enhanced high-temperature mechanical properties are *** this work,a novel(b4 C+Al_(2)O_(3))/Al NAM with netlike distribution of Al_(2)O_(3)was fabricated by powder metallurgy method and subjected to high-temperature tensile creep *** was shown that the creep resistance was enhanced by several orders of magnitude via the addition of only2.1 vol.%netlike-distributed Al_(2)O_(3).(b_(4)C+Al_(2)O_(3))/Al exhibited high apparent stress exponents ranging from 16 to 25 and high apparent activation energy of 364 kJ/*** creep behaviour could be rationalized using the substructure-invariant model and its rupture behaviour could be described by the Dobes-Milicka equation.

关键词： Neutron absorber material Al matrix composite Tensile creep b_(4)C/Al

Synthesis and Erosion behaviors of Nanoscale Coatings Prepared by Wire Arc Spraying

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稀有金属材料与工程 2012年第S1期41卷 144-147页

作者： Cheng, J. b. Xiang, X. b. Wang, z. H. Xu, b. S. Hohai Univ Coll Mech & Mat Nanjing 210098 Jiangsu Peoples R China Natl Key Lab Remfg Beijing 100072 Peoples R China

The effects of erosive parameters,such as impact angles and environment temperature,on erosion properties of FebSiCrMnNb nanoscale coatings were investigated.A series of coatings were prepared by wire arc spraying *** microstructure of the coating consists of amorphous andα(Fe,Cr)nanocrystalline *** nanocrystals with average size of 39 nm are homogenously dispersed in amorphous *** erosion results reveal that the coating exhibits better erosion resistance at lower impact *** erosion rates of the coating decrease as function of environment *** relatively erosion resistance of the nanoscale coating is 3.7 times higher than that of AISI1045 steel substrate at 650°*** main failure mechanism of the coating is brittle fracture.

关键词： coatings nano materials abrasive

Refining constitutive relation by integration of finite element simulations and Gleeble experiments

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Journal of Materials Science & Technology 2019年第6期35卷 1039-1043页

作者： D.J. Yu D.S. Xu H. W ang z.b. zhao G.z. Wei R. Yang College of Sciences Northeastern University Shenyang 110004 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Thermo-mechanical coupled finite element calculations were carried out to simulate the Gleeble compression of the samples of a titanium alloy(Ti60), and the results are analyzed and compared with the actual compression tests conducted on a Gleeble 3800 thermo-mechanical simulator. The changes in temperature, stress and strain distribution in the samples and the source of error on the constitutive relations from Gleeble hot compression test were analyzed in detail. both simulations and experiments showed that the temperature distribution in the specimen is not uniform during hot compression, resulting in significant deformation inhomogeneity and non-ignorable error in the flow stress strain relation,invalidating the uniform strain assumption commonly assumed when extracting the constitutive relation from Gleeble tests. based on the finite element simulations with iterative corrections, we propose a scheme to refine the constitutive relations from Gleeble tests.

关键词： Titanium alloy Constitutive relation Finite element Compression Temperature distribution

Recent development of chemically complex metallic glasses: from accelerated compositional design, additive manufacturing to novel applications

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Materials Futures 2022年第1期1卷 9-31页

作者： J Y zhang z Q zhou z b zhang M H Park Q Yu z Li J Ma A D Wang H G Huang M Song b S Guo Q Wang Y Yang Department of Mechanical Engineering College of EngineeringCity University of Hong KongKowloon TongKowloonHong KongPeople’s Republic of China Shenzhen Key Laboratory of High Performance Nontraditional Manufacturing College of Mechatronics and Control EngineeringShenzhen UniversityShenzhenGuangdong 518060People’s Republic of China School of Materials Science and Engineering Dongguan University of TechnologyDongguanGuangdong 523808People’s Republic of China Institute of Materials China Academy of Engineering PhysicsJiangyouSichuan 621907People’s Republic of China State Key Laboratory of Powder Metallurgy Central South UniversityChangshaHunan 410083People’s Republic of China Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhouGuangdong 510632People’s Republic of China Institute of Materials Laboratory for MicrostructuresShanghai UniversityShanghai 200444People’s Republic of China Department of Materials Science and Engineering College of EngineeringCity University of Hong KongKowloon TongKowloonHong KongPeople’s Republic of China Department of Advanced Design and System Engineering College of EngineeringCity University of Hong KongKowloon TongKowloonHong KongPeople’s Republic of China

Metallic glasses(MGs)or amorphous alloys are an important engineering material that has a history of research of about 80–90 *** different fast cooling methods were developed for multi-component MGs between 1960s and 1980s,1990s witnessed a surge of research interest in the development of bulk metallic glasses(bGMs).Since then,one central theme of research in the metallic-glass community has been compositional design that aims to search for MGs with a better glass forming ability,a larger size and/or more interesting properties,which can hence meet the demands from more important *** this review article,we focus on the recent development of chemically complex MGs,such as high entropy MGs,with new tools that were not available or mature yet until recently,such as the state-of-the-art additive manufacturing technologies,high throughput materials design techniques and the methods for big data analyses(*** learning and artificial intelligence).We also discuss the recent use of MGs in a variety of novel and important applications,from personal healthcare,electric energy transfer to nuclear energy that plays a pivotal role in the battle against global warming.

关键词： metallic glasses amorphous alloys alloy design additive manufacturing machine learning high throughput materials design

Predicting the variation of stacking fault energy for binary Cu alloys by first-principles calculations

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Journal of Materials Science & Technology 2020年第18期52卷 61-65页

作者： T.Cai K.Q.Li z.J.zhang P.zhang R.Liu J.b.Yang z.F.zhang Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province College of Advanced Materials and EnergyInstitute of Surface Micro and Nano MaterialsXuchang UniversityXuchang 461000China Laboratory of Fatigue and Fracture for Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

The variation of stacking fault energy(SFE)in a number of binary Cu alloys is predicted through considering the Suzuki segregation by the full potential linearly augmented plane wave(FPLAPW)*** calculated results show that some solute atoms(Mg,Al,Si,zn,Ga,Ge,Cd,Sn,and Pb),which prefer to form the Suzuki segregation,may decrease the value of SFE;while the others(Ti,Mn,Fe,Ni,zr,Ag,and Au),which do not cause the Suzuki segregation may not decrease the ***,it is interesting to find that the former alloying elements are located on the right of Cu group while the latter on the left of Cu group in the periodic table of *** intrinsic reasons for the new findings can be traced down to the valences electronic structure of solute and Cu atoms,i.e.,the similarity of valence electronic structure between solute and Cu atoms increases the value of SFE,while the difference decreases the value of SFE.

关键词： Cu-alloy Deformation behavior First-principles calculation Stacking fault energy