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Receiver function imaging of dense seismic array and deep dynamic mechanism beneath the eastern South China

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Science China Earth Sciences 2023年第6期66卷 1289-1308页

作者： Rubing HAN Dinghui YANG Qiusheng LI Rong HUANG hongshuang zhang Jiangtao LI Hao CHEN Zhuo YE Wei FU Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Institute of Geophysics and Geomatics China University of GeosciencesWuhan 430074China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330001China SinoProbe Center Chinese Academy of Geological SciencesBeijing 100037China College of Transportation Engineering Nanjing Tech UniversityNanjing 211816China

The Mesozoic tectonic framework of the eastern South China is mainly controlled by subduction,turning toward,and rollback of the Pacific *** studies of receiver function imaging and ambient noise tomography have revealed the“Yshaped”thinnest crustal belt in the eastern South China under the overall extension of the ***,the deep dynamic environment and formation mechanisms of the thin crustal belt remain *** we obtained high-resolution images of the crustal thickness and Poisson’s ratio in the eastern South China Block applying the recently proposed H-κ-c receiver function method,using data recorded by 305 dense portable broadband stations and 219 permanent stations ***,we discussed the deep dynamic formation mechanism of the“Y-shaped”thinnest crustal belt coupled with two common conversion point stacked images at key *** show that the average crustal thickness of the study area is 33 km(thin crust)and the average Poisson’s ratio is 0.24(low ratio).The overall crustal thinning toward the continental margin is likely because eastern South China was in a back-arc extension environment,which was induced by the rollback of the subducted plate in the Early *** crustal thickness of the“Y-shaped”thinnest crustal belt is<30 km,which is 3-5 km thinner than that outside the *** eastern branch is distributed along the trajectory of Nanchang-Ji’an-Ganzhou-Shaoguan-Guangzhou,and the western branch is around the Jianghan-Xiangzhong Basin,both of which intersect in *** eastern branch of the thin crustal zone indicates the potential location of the Pacific subduction slab breakoff,and the formation mechanism may be related to the interaction of deep-shallow processes,including the upwelling of mantle heat flow through the slab window and transtensional pre-existing *** developed a dynamic model that combines subduction-breakoff-rollback processes of the Paleo-Pacific Plate and accomp

关键词： Eastern South China Block Dense seismic array Receiver function “Y-shaped”thinnest crustal belt Slab breakoff

A thinned lithosphere beneath coastal area of southeastern China as evidenced by seismic receiver functions

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Science China Earth Sciences 2014年第11期57卷 2835-2844页

作者： YE Zhuo LI QiuSheng GAO Rui zhang hongshuang HE RiZheng WANG HaiYan LI WenHui Institute of Geology Chinese Academy of Geological Sciences Key Laboratory of Earthprobe and Geodynamics Ministry of Land and Resources

During Mesozoic to Cenozoic time, the large-scale tectono-magmatism had strongly modified the lithosphere beneath the southeastern continent of China, leaving the present-day lithosphere as a new one evolving from the ancient lithosphere that was largely removed and replaced. But this model proposed from geochemical and petrological research is urgently in need of support from seismic observational evidence. In this paper, based on the dataset recorded by the dense stations of two NE ori- ented broadband seismic profiles deployed in the coastal area of southeastern China （SE China）, both P-wave （P-RF） and S-wave （S-RF） receiver functions were isolated. We identified Pls phase converted from the Lithosphere-Asthenosphere Boundary （LAB） in P-RFs of individual stations. Migrated Pls phase indicated a depth of 60-70 km for LAB. Inver- sions/comparisons of P-RF （Pls phase） and S-RF （Sip phase） waveforms together with Ps and Sp imaging for the crust and up- per mantle structure further confirmed this result. P-RF and S-RF migrated images exhibit that a flat LAB is positioned at the depth of 60-70 km spreading along the profile, whereas a distinct structural change of lithospheric base appears at the Min River estuary. Both Ps and PpPs migrated images of P-RFs present an abrupt Moho drop across the Min River fault from south to north, which is consistent with previous result obtained from deep seismic sounding. By taking into consideration other ge- ological and geophysical features such as locally high anomalies of crustal Poisson＇s ratios and heat flow at the Min River es- tuary, we infer that the Min River fault penetrates down to the Moho and may, furthermore, interfere in the deeper lithospheric structure.

关键词： SE China lithospheric thinning LAB Moho receiver functions Min River fault

Microstructure and Eutectic Carbide Morphology of the High Speed Steel Strips Produced by Twin Roll Strip Casting Process

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Journal of Materials Science & Technology 2003年第5期19卷 472-474页

作者： hongshuang DI, Xiaoming zhang, Guodong WANG and Xianghua LIUState Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110004, China State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 China

The M2 high-speed steel strip was produced by using the laboratory scale twin roll strip caster. The microstructure and eutectic carbide morphology of thus produced products were observed and analyzed, and the comparison of those with conventional products was carried out. The effects of the processing parameters such as the melting temperature, the pouring temperature, rolling speed and separating force on the microstructure and eutectic carbide morphology and their distribution were analyzed. The spheroidizing process of the strips in the annealing process was investigated. The relations between the growth and spheroidizing of the eutectic carbide and the annealing technology were obtained, and the mechanism of the twin roll strip casting process improving the eutectic carbide spheroidizing was discussed. The theoretical instruction for determining the subsequent treatment process was provided.

关键词： Twin roll strip casting High speed steel Eutectic carbide Microstructure

Two Dimension Finite Element Simulations on the Electromagnetic Containment in Twin-Roll Strip Casting

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Journal of Materials Science & Technology 2003年第1期19卷 9-12页

作者： Peiwei BAO, hongshuang DI, Xiaoming zhang, Guodong WANG and Xianghua LIUState Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110004, China Lab. of Rolling and Automat. Northeastern Univ. Shenyang 110004 China

Distribution of magnetic field and electromagnetic force in twin-roll casting of steels was studied by the method of numericalsimulation in this paper. Two-dimension finite element model, which includes the regions of melt, stainless collar, coil andmagnetic core, has been constructed. By solving magnetic vector potential formulations of quasi-static electromagnetic field,distribution of magnetic flux density and magnetic force at different molten height is determined. Calculated results showedthat intensity of the distribution of magnetic flux density increased linearly with the increased coil current; and the magneticforce in the melt increased as a quadratic cure with creased coil current. More attention was given to the distribution of eddycurrent and magnetic force in the melt, the confine effect at different molten height was also discussed.

关键词： Twin roll casting Electromagnetic field Electromagnetic containment Simulation Finite element

Prevalent thickening and local thinning of the mantle transition zone beneath the Baikal rift zone and its dynamic implications

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Prevalent thickening and local thinning of the mantle transi...

Lithospheric thickness and upper-mantle deformation beneath the NE Tibetan Plateau inferred from S receiver functions and SKS splitting measurements

中国科学院地质与地球物理研究所2013年度（第13届）学术年会

作者： SI ShaoKun TIAN XiaoBo zhang hongshuang TENG JiWen Institute of Geology and Geophysics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

The Baikal rift is the most seismically active continental rift in the world and is significant for studying the dynamics of continental rifts,although its precise dynamic mechanisms remain *** calculated receiver functions(1748)from Global Seismographic Network seismic stations TLY and ULN and stacked receiver functions in different *** we present discontinuities at depths of 410 km and 660 km and thickness of the mantle transition zone(MTZ)beneath the study area. The MTZ structure shows an obvious thickening(292 km)in the Baikal rift zone except for an area of limited thinning(230 km),whereas it is basically normal(250 km)beneath the Mongolian area,to the southeast of the Baikal *** these results with previous findings,we propose that the large-scale thickening beneath the Baikal rift zone is likely to be caused by the Mesozoic collision between the Siberian Platform and the Mongolia-North China Block or magmatic intrusion into the lower crust,which would result in crust and lithosphere ***,the lower crust becomes eclogitized and consequently detached into the deep mantle because of negative *** detachment not only induces asthenosphere upwelling but also accelerates mantle convection of water detached from the subducted slab,which would increase mantle melting,while both processes promote the development of the *** preliminary results indicate that the detachment and the consequent hot upwelling have an important influence on the development of the Baikal rift,and a small-scale mantle upwelling indicated by the located thinning may have destroyed the lithosphere and promoted this development.

关键词： Baikal rift zone mantle transition zone P wave receiver function

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Lithospheric thickness and upper-mantle deformation beneath ...

低碳低合金无碳化物贝氏体钢热处理工艺及组织性能研究

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： hongshuang zhang Jiwen Teng Xiaobo Tian Zhongjie zhang Rui Gao Jiaqi Liu Institute of Geology Chinese Academy of Geological Sciences Institute of Geology and Geophysics Chinese Academy of Sciences

We present S receiver functions and SKS splitting measurements from the China Seismograph Network located in the Qinghai and Gansu *** data are used to interpret the structure of the lithosphere-asthenosphere boundary(LAB) and upper-mantle deformation beneath the northeastern Tibetan Plateau(NETP) in regions north of the east Kunlun Fault. Based on our observations,the LAB lies at a depth of 125-135 km beneath the northeastern Songpan-Ganzi block and the west Qinling orogen,between 145 and 175 km beneath the Kunlun and Qilian orogen,and deepens below the Qaidam Basin(175-190 km),Ordos Craton (170 km) and Alashan platform(200 km).The NETP is characterized by a nearly uniform fast NW-SE 5-wave *** observations are different from those to the south of the Kunlun Fault where fast S directions are rotating clockwise from the inner *** change in fast directions across the Kunlun Fault implies a sudden variation of upper-mantle *** wave splitting delay times vary from 0.8 to 1.9 *** from beneath regions north of the Kunlun-Ayimaqin suture showed that delay time was positively correlated with lithospheric thickness with an increase of 0.7 s per 100 *** indicates that the anisotropy may develop in the uppermost mantle,such as the lithosphere,beneath the NETP.

关键词： Body waves Seismic anisotropy Continental tectonics:extensional Dynamics of lithosphere and mantle

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热加工工艺 2024年第17期53卷 140-145页

作者：苏震邸洪双张天宇柯浩鹏东北大学轧制技术及连轧自动化国家重点实验室辽宁沈阳110819

开展了实验钢在Ms点以上及以下保温不同时间的等温淬火实验,结合高分辨膨胀仪、电子背散射衍射(EBSD)、X射线衍射(XRD)等其它实验手段,探究了引入一次马氏体对贝氏体相变动力学的影响,以及不同等温时间转变后微观组织和力学性能之间的... 详细信息

开展了实验钢在Ms点以上及以下保温不同时间的等温淬火实验,结合高分辨膨胀仪、电子背散射衍射(EBSD)、X射线衍射(XRD)等其它实验手段,探究了引入一次马氏体对贝氏体相变动力学的影响,以及不同等温时间转变后微观组织和力学性能之间的关系。结果表明,在Ms点以下等温阶段引入的一次马氏体显著地加速了贝氏体相变动力学,并且提高了实验钢的屈服强度和伸长率。这是因为引入的一次马氏体为贝氏体提供了更多的形核界面,并且获得了由回火马氏体、二次马氏体、贝氏体和残余奥氏体组成的多相组织,其中较多数量的残余奥氏体因TRIP效应从而使实验钢的塑性提高。实验钢在300℃等温2 h后,其抗拉强度、屈服强度分别为1475、986 MPa,伸长率高达18.5%。

关键词：无碳化物贝氏体钢热处理工艺微观组织力学性能

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一种可分离式大葱收割打捆机的研究

机械设计 2024年第S1期41卷 83-87页

作者：张恒国李红双余飞扬沈阳航空航天大学机电工程学院辽宁沈阳110136

针对目前大葱收割问题,研制出一款小型的可分离式大葱收割打捆机。该机器由收割装置和打捆装置两部分组成。通过SolidWorks三维软件对结构进行设计,并对控制部分进行研究,制作出实物模型,试验研究表明:收割单根大葱所需时间大约为11.01... 详细信息

针对目前大葱收割问题,研制出一款小型的可分离式大葱收割打捆机。该机器由收割装置和打捆装置两部分组成。通过SolidWorks三维软件对结构进行设计,并对控制部分进行研究,制作出实物模型,试验研究表明:收割单根大葱所需时间大约为11.01 s,打捆单根所需时间为30.69 s,以10根大葱为例,收割与打捆同时进行时所需时间为143.13 s。该机器相对于大型收割农机较小,并可以通过手机远程操控,更加方便与实用,适用于中小型农户与家庭。

关键词：大葱收割机结构设计试验测试

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基于PLC和触摸屏的便携式电机控制实验台

实验室科学 2022年第4期25卷 77-80页

作者：张洪双史中权楼力律河海大学机电工程学院江苏常州213022

为提升学生理论联系实际的能力,研制了一套基于PLC和触摸屏的便携式电机控制实验台,通过AD转换模块、控制按钮、指示灯和各类驱动模块等元器件对步进电机进行调速、寸动、点动和回零等控制,对直流电机进行启动、调速、测速等控制,直流... 详细信息

为提升学生理论联系实际的能力,研制了一套基于PLC和触摸屏的便携式电机控制实验台,通过AD转换模块、控制按钮、指示灯和各类驱动模块等元器件对步进电机进行调速、寸动、点动和回零等控制,对直流电机进行启动、调速、测速等控制,直流电机的转动圈数通过指示灯变换指示。此外,可以通过触摸屏实现相同功能的控制和显示。该实验台的结构简单,便于携带,既可作为教师授课的演示教具,也可作为学生的实验平台,可有效地提升课程和实验的教学效果。

关键词：可编程逻辑控制器触摸屏便携式电机控制实验台