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Atomistic Investigation of Shock-Induced Amorphization within Micro-shear Bands in Hexagonal Close-Packed Titanium

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1590-1600页

作者： Z.C.Meng K.G.Wang T.Ali D.Li C.G.Bai D.S.Xu S.J.Li A.H.Feng G.J.Cao J.H.Yao Q.B.Fan H.Wang r.yang Institute of Metal research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Interdisciplinary Centre for Additive Manufacturing(ICAM) School of Materials and ChemistryUniversity of Shanghai for Science and TechnologyShanghai 200093China School of Materials Science and Engineering Tongji UniversityShanghai 201804China Key Laboratory for Light-Weight Materials Nanjing Tech UniversityNanjing 210009China National Key Laboratory of Science and Technology on Materials Under Shock and Impact School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401135China

The mechanical response of a single crystal titanium sample against(0001)α surface impact was investigated using molecular dynamics ***,non-uniform plastic deformation was observed in the *** high strain rates,amorphization occurred near the edge of the contact region where severe shear strain induced a large number of stacking faults(SFs)and *** contrast,the central part of the contact region underwent less deformation with significantly fewer ***,instead of amorphization by consuming SFs and dislocations,there was a gradual increase in the density of dislocations and SFs during the process of *** local amorphous regions eventually grew into shear bands.

关键词： Shock compression Amorphization Shear band Titanium Molecular dynamics

地壳浅部S波速度结构的多频接收函数两步反演法及其在中国东北盆-山构造区的应用

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中国科学：地球科学 2024年第3期54卷 708-724页

作者：杨睿豪王旭陈凌冯铭业陈棋福中国科学院地质与地球物理研究所岩石圈演化国家重点实验室北京100029 中国科学院大学地球与行星科学学院北京100049 中国科学院地质与地球物理研究所中国科学院地球与行星物理重点实验室北京100029

地壳浅部(<10km)速度模型既是地壳结构与变形研究和资源勘探前景评估的基础,又可为壳幔深部结构成像等研究提供先验信息.针对区域尺度结构,被动源方法相比主动源方法具有明显优势.被动源方法中,基于接收函数和/或体波振幅比的成像方法... 详细信息

地壳浅部(<10km)速度模型既是地壳结构与变形研究和资源勘探前景评估的基础,又可为壳幔深部结构成像等研究提供先验信息.针对区域尺度结构,被动源方法相比主动源方法具有明显优势.被动源方法中,基于接收函数和/或体波振幅比的成像方法由于具有较高空间分辨率,近年来受到广泛关注.然而,盆地松散沉积层内部的反射混响常导致此类方法表现出较强的多解性及不确定性,限制了其应用.因此,本文提出一种基于多频径向接收函数波形及其与垂向接收函数振幅比的两步反演法,以约束地壳浅部S波速度结构.理论测试表明,两步反演策略能有效降低反演多解性、提高结果稳定性.将该方法应用于一条横跨中国东北沉积盆地的线性地震台阵数据,获得了地壳浅部S波速度精细结构图像.结果显示,盆地与山地地壳浅部结构差异显著:二连盆地浅部(<1.0km)和松辽盆地浅部(<2.5km)速度较低(<2.8km s^(-1)),反映低速沉积层;松辽盆地7km以深地壳速度较高(3.4~3.8km s^(-1)),可能反映早白垩世镁铁质岩浆侵入体.此外,成像结果中速度异常分布与盆地内大型断裂、隆起及沉积凹陷等构造的地表位置吻合,速度异常延深深度也与已有地震勘探结果相吻合.这些观测表明,两步反演法能有效约束松散沉积盆地S波速度随深度变化特征,并实现区域尺度地壳浅部结构高精度成像.

关键词：接收函数频率依赖性两步反演地壳浅部S波速度结构松散沉积盆地

STUDY ON DISLOCATION STrUCTUrES IN WELDED METALS UNDEr FATIGUE LOAD

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Acta Metallurgica Sinica(English Letters) 1999年第4期12卷 340-344页

作者： yang, H.r. Shenyang Univ Shenyang China

With transmission electron microscope, it has been observed and analyzed that the dislocation arrangements and the fatigue damage of eutectoid present in welded metals which are loaded at different fatigue loads and load cycles. The results indicated that the character of fatigue damage in ferrites of welded metals is the dislocation arrangement change and eutectoids of welded metals are the broken cementites. This may produce microcracks.

关键词： Crack initiation Dislocations (crystals) Fatigue of materials Ferrite Transmission electron microscopy Welded steel structures

Characterization of water-in-crude oil emulsions in oil spill response

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Journal of Environmental Sciences 2003年第4期15卷 506-509页

作者： MATHEr r.r. FOTHErINGHAM A.F. yang r.D. HeriotWattUniversityScottishBordersCampus HeriotWattUniversityScottishBordersCampusHeriotWattUniversityScottishBordersCampus GalashielsUKGalashielsUKGalashielsUK

The formation of water in crude oil emulsions occurs when crude oils are spilled into sea. The water in crude oil emulsions significantly change the properties of the spilled crude oils and in turn influence the choices made relating to oil spill countermeasures. The water in crude oil emulsions were characterized using various techniques in this study. The environmental scanning electron microscopy observation of water droplets in the emulsions is also presented. It is a powerful tool in emulsion observations.

关键词： oil spill water in oil emulsions oil spill response DSC ESEM

Structural and functional variations of phytoplankton communities in the face of multiple disturbances

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Journal of Environmental Sciences 2021年第2期33卷 287-297页

作者： Jun r.yang Xiaoqing Yu Huihuang Chen Yi-Ming Kuo Jun yang Engineering research Center of Ecology and Agricultural Use of wetland(Ministry of Education)College of Agriculture Yangtze UniversityJingzhou 434025China Aquatic Ecohealth Group Fujian Key Laboratory of Watershed EcologyKey Laboratory of Urban Environment and HealthInstitute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China School of Environmental Studies China University of GeosciencesWuhan 430074China

The global decline of freshwater biodiversity caused by climate change and human activities are supposed to disrupt ecosystem services related to water quality and alter the structure and function of aquatic communities across space and time,yet the effects of the combination of these factors on plankton community ecosystem has received relatively little *** study aimed to explore the impacts of disturbances(*** activity,temperature,precipitation,and water level)on phytoplankton community structure(*** evenness and community composition)and function(*** use efficiency)in four subtropical reservoirs over 7 years from 2010 to *** results showed that community turnover(measured as community dissimilarity)was positively related to disturbance frequency,but no significant correlation was found between phytoplankton biodiversity(***)and disturbance *** resource use efficiency(rUE=phytoplankton biomass/total phosphorus)was increased with a higher frequency of disturbance with an exception of *** rUE of Cyanobacteria and diatoms showed significantly negative correlations with their community evenness,while the rUE of Chlorophyta exhibited a positive correlation with their community *** suggest that multiple environmental disturbances may play crucial roles in shaping the structure and functioning of plankton communities in subtropical reservoirs,and mechanism of this process can provide key information for freshwater uses,management and conservation.

关键词： Algae Biodiversity Community ecology Plankton resource use efficiency Subtropical reservoir

Urbanization reduces resource use efficiency of phytoplankton community by altering the environment and decreasing biodiversity

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Journal of Environmental Sciences 2022年第2期34卷 140-151页

作者： Yigang yang Huihuang Chen Mamun Abdullah Al Jean Claude Ndayishimiye Jun r yang Alain Isabwe Anqi Luo Jun yang Aquatic EcoHealth Group Fujian Key Laboratory of Watershed EcologyKey Laboratory of Urban Environment and HealthInstitute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Engineering research Center of Ecology and Agricultural Use of Wetland(Ministry of Education) College of AgricultureYangtze UniversityJingzhou 434025China

Urbanization often exerts multiple effects on aquatic and terrestrial organisms,including changes in biodiversity,species composition and ecosystem ***,the impacts of urbanization on river phytoplankton in subtropical urbanizing watersheds remain largely ***,we explored the effects of urbanization on phytoplankton community structure(i.e.,biomass,community composition and diversity)and function(i.e.,resource use efficiency)in a subtropical river at watershed scale in southeast China over 6 years.A total of 318 phytoplankton species belonging into 120 genera and 7 phyla were identified from 108 *** biomass showed an increasing trend with increasing urbanization *** phytoplankton community shifted from Chlorophyta dominance in rural upstream waters to Bacillariophyta dominance in urbanized downstream ***,phytoplankton diversity and resource use efficiency(rUE=phytoplankton biomass/total phosphorus)were significantly decreased with increasing urbanization level from upstream to *** rUE exhibited a significant positive correlation with species richness,but a negative correlation with phytoplankton *** variation in environmental factors(turbidity,total nitrogen,NH_(4)^(+)-N,total phosphorus,PO_(4)^(3-)-P and percentage urbanized area)was significantly correlated with phytoplankton diversity and ***,our results revealed the influence of urbanization on phytoplankton community structure and ecosystem function was due to its altering the environmental ***,human-driven urbanization may play crucial roles in shaping the structure and function of phytoplankton communities in subtropical rivers,and the mechanism of this process can provide important information for freshwater sustainable uses,watershed management and conservation.

关键词： Plankton Community functioning Subtropical river Urbanization gradient Land use Watershed ecology

STCF conceptual design report (Volume 1): Physics & detector

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Frontiers of physics 2024年第1期19卷 1-154页

作者： M.Achasov X.C.Ai L.P.An r.Aliberti Q.An X.Z.Bai Y.Bai O.Bakina A.Barnyakov V.Blinov V.Bobrovnikov D.Bodrov A.Bogomyagkov A.Bondar I.Boyko Z.H.Bu F.M.Cai H.Cai J.J.Cao Q.H.Cao X.Cao Z.Cao Q.Chang K.T.Chao D.Y.Chen H.Chen H.X.Chen J.F.Chen K.Chen L.L.Chen P.Chen S.L.Chen S.M.Chen S.Chen S.P.Chen W.Chen X.Chen X.F.Chen X.r.Chen Y.Chen Y.Q.Chen H.Y.Cheng J.Cheng S.Cheng T.G.Cheng J.P.Dai L.Y.Dai X.C.Dai D.Dedovich A.Denig I.Denisenko J.M.Dias D.Z.Ding L.Y.Dong W.H.Dong V.Druzhinin D.S.Du Y.J.Du Z.G.Du L.M.Duan D.Epifanov Y.L.Fan S.S.Fang Z.J.Fang G.Fedotovich C.Q.Feng X.Feng Y.T.Feng J.L.Fu J.Gao Y.N.Gao P.S.Ge C.Q.Geng L.S.Geng A.Gilman L.Gong T.Gong B.Gou W.Gradl J.L.Gu A.Guevara L.C.Gui A.Q.Guo F.K.Guo J.C.Guo J.Guo Y.P.Guo Z.H.Guo A.Guskov K.L.Han L.Han M.Han X.Q.Hao J.B.He S.Q.He X.G.He Y.L.He Z.B.He Z.X.Heng B.L.Hou T.J.Hou Y.r.Hou C.Y.Hu H.M.Hu K.Hu r.J.Hu W.H.Hu X.H.Hu Y.C.Hu J.Hua G.S.Huang J.S.Huang M.Huang Q.Y.Huang W.Q.Huang X.T.Huang X.J.Huang Y.B.Huang Y.S.Huang N.Hüsken V.Ivanov Q.P.Ji J.J.Jia S.Jia Z.K.Jia H.B.Jiang J.Jiang S.Z.Jiang J.B.Jiao Z.Jiao H.J.Jing X.L.Kang X.S.Kang B.C.Ke M.Kenzie A.Khoukaz I.Koop E.Kravchenko A.Kuzmin Y.Lei E.Levichev C.H.Li C.Li D.Y.Li F.Li G.Li G.Li H.B.Li H.Li H.N.Li H.J.Li H.L.Li J.M.Li J.Li L.Li L.Li L.Y.Li N.Li P.r.Li r.H.Li S.Li T.Li W.J.Li X.Li X.H.Li X.Q.Li X.H.Li Y.Li Y.Y.Li Z.J.Li H.Liang J.H.Liang Y.T.Liang G.r.Liao L.Z.Liao Y.Liao C.X.Lin D.X.Lin X.S.Lin B.J.Liu C.W.Liu D.Liu F.Liu G.M.Liu H.B.Liu J.Liu J.J.Liu J.B.Liu K.Liu K.Y.Liu K.Liu L.Liu Q.Liu S.B.Liu T.Liu X.Liu Y.W.Liu Y.Liu Y.L.Liu Z.Q.Liu Z.Y.Liu Z.W.Liu I.Logashenko Y.Long C.G.Lu J.X.Lu N.Lu Q.F.Lü Y.Lu Y.Lu Z.Lu P.Lukin F.J.Luo T.Luo X.F.Luo Y.H.Luo H.J.Lyu X.r.Lyu J.P.Ma P.Ma Y.Ma Y.M.Ma F.Maas S.Malde D.Matvienko Z.X.Meng r.Mitchell A.Nefediev Y.Nefedov S.L.Olsen Q.Ouyang P.Pakhlov G.Pakhlova X.Pan Y.Pan E.Passemar Y.P.Pei H.P.Peng L.Peng X.Y.Peng X.J.Peng K.Peters S.Pivovarov E.Pyata B.B.Qi Y.Q.Qi W.B.Qian Y.Qian C.F.Qiao J.J.Qin J.J.Qin L.Q.Qin X.S.Qin T.L.Qiu J.rademacker C.F.redmer H.Y.Sang Anhui University Hefei 230039China Beihang University Beijing 100191China Budker Institute of Nuclear Physics Novosibirsk 630090Russia CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Cavendish Laboratory University of CambridgeJJ Thomson AveCambridge CB30HEUnited Kingdom Central China Normal University Wuhan 430079China Central South University Changsha 410083China China University of Geosciences Wuhan 430074China China University of Mining and Technology Xuzhou 221116China École Polytechnique Fédérale de Lausanne(EPFL) LausanneSwitzerland Fudan University Shanghai 200433China Goethe University Frankfurt D-60325 Frankfurt am MainGermany Guangxi Normal University Guilin 541004China Guangxi Uninversity Nanning 530004China Hangzhou Institute for Advanced Study UCASHangzhou 310024China Hebei Normal University Shijiazhuang 050024China Hebei University Baoding 071002China Hefei University of Technology Hefei 230601China Helmholtz Institute Mainz Staudinger Weg 18D-55099 MainzGermany Henan Normal University Xinxiang 453007China Henan University Kaifeng 475004China High Energy Physics Center Chung-Ang UniversitySeoul 06974Korea Higher School of Economy 11 Pokrovsky Bulvar Moscow 109028Russia Huangshan University Huangshan 245000China Hubei University of Automotive Technology Shiyan 442002China Hunan Normal University Changsha 410081China Hunan University of Science and Technology Xiangtan 411201China Hunan University Changsha 410082China Indiana University BloomingtonIndiana 47405USA Inner Mongolia University Hohhot 010021China Institute of Advanced Science Facilities Shenzhen 518107China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Institute of Physics Academia SinicaTaipeiTaiwan 11529China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China Jilin University Changch

The superτ-charm facility(STCF)is an electron–positron collider proposed by the Chinese particle physics *** is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of 0.5×10^(35) cm^(–2)·s^(–1) or *** STCF will produce a data sample about a factor of 100 larger than that of the presentτ-charm factory—the BEPCII,providing a unique platform for exploring the asymmetry of matter-antimatter(charge-parity violation),in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions,as well as searching for exotic hadrons and physics beyond the Standard *** STCF project in China is under development with an extensive r&D *** document presents the physics opportunities at the STCF,describes conceptual designs of the STCF detector system,and discusses future plans for detector r&D and physics case studies.

关键词： electron–positron collider tau-charm region high luminosity STCF detector conceptual design

Molecular Dynamics Simulation of Tensile Deformation and Fracture of γ-TiAl with and without Surface Defects

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Journal of Materials Science & Technology 2016年第10期32卷 1033-1042页

作者： H.N.Wu D.S.Xu H.Wang r.yang Institute of Metal research Chinese Academy of Sciences

Molecular dynamics simulation of uniaxial tension along [001] has been performed to study the influence of various surface defects on the initiation of plastic deformation and fracture of γ-TiAl single *** results indicate that brittle fracture occurs in perfect bulk; surfaces and edges will be detrimental to the strength of materials and provide dislocation nucleation site. The defects on surfaces and edges cause further weakening with various effects depending on defect type, size, position and orientation,while the edge dimples are the most influential. For γ-TiAl rods with surface dimples, dislocations nucleate from an edge of the rod when dimples are small, dimple dislocation nucleation occurs only when the dimples are larger than a strain rate dependent critical size. The dislocations nucleated upon [001]tension are super dislocations with Burger vectors 〈011] or 1/2 〈 112] containing four 1/6 〈 112 〉 partials. The effects of surface scratches are orientation and shape sensitive. Scratches parallel to the loading direction have little influence, while sharp ones perpendicular to the loading direction may cause crack and thus should be avoided. This simulation also shows that, any type of surface defect would lower strength,and cause crack in some cases. But some may facilitate dislocation nucleation and improve ductility of TiAl if well controlled.

关键词： Intermetallic compounds Superdislocation Fracture Surface defects Molecular dynamics

Distinct dendritic α phase emerging on the surface of primary α phase in a compressed near-α titanium alloy

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Journal of Materials Science & Technology 2018年第4期34卷 666-669页

作者： Z.Liu Z.B.Zhao J.r.Liu Q.J.Wang r.yang Institute of Metal research Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China

The characteristic of the surface morphology of primary α phase was studied in a deformed near-α tita- nium alloy. Dendritic α phase emerged on the surfaces of primary α phase when the alloy was air-cooled in α ＋β phase field after deformation. The dendritic α grain has the same orientation with its original primary α grain. The formation of the dendritic α phase could be explained by interface instability in epi- taxial growth process of the primary α phase. The dislocations induced by deformation could facilitate the formation of dendritic α phase leading to the dendritic α phase and more obvious with the increase of strain. The growth of dendritic α phase was finally limited by the nucleation of second α phase with cooling.

关键词： Epitaxial growth Dendritic α phase Microstructure Interface instability Hot deformation