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Upper-Mantle Velocity Heterogeneity of Eastern Tibetan Plateau from Teleseismic P-Wave Tomography and Its Tectonic Implications

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Journal of Earth Science 2023年第1期34卷 280-290页

作者： Shahpara Sheikh Dola junmeng zhao heng zhang Shunping Pei State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100049China Nuclear Safety Security&Safeguards Division(NSSSD)Bangladesh Atomic Energy Regulatory Authority(BAERA)Dhaka1207Bangladesh

An attempt has been made to reveal the upper mantle velocity structure of the eastern Tibetan Plateau using 628 teleseismic events recorded from 2003 to 2009 at 95 stations.A total of 8 532 Pwave arrival time residuals were inverted by using the FMTOMO(fast marching tomography) software *** results show upper mantle velocity heterogeneity in many *** the southern part visible high velocity anomaly is denoted as the Indian *** part seems to be affected by slab tearing at 940E longitude as it is located on the eastern Himalayan syntaxis(EHS).The high velocity zone down to 500 km depth in the northern part could be the Asian *** the central part some high velocity anomalies can be identified as detached patches of the lithosphere,surrounded by low velocity *** anomalies are the potential to create thermal convection and trigger plateau uplift or plateau *** velocity change occurs on both sides of patches where low velocity anomaly is visible in between patches and Bangong-Nujiang suture even in between Songpan-Ganzi terrain and Asian *** both cases intense low velocity zone spread down to 500 *** depth range of low velocity anomalies in between two plates observed from 200 to-500 *** the low velocity anomalies detected in our results may reflect either the hot asthenosphere upwelling or the mantle wedge due to the presence of the cold lithosphere.

关键词： upper mantle tomography eastern Tibetan Plateau FMTOMO velocity heterogeneity

6082铝合金冷塑性流变行为及数值模拟研究

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塑性工程学报 2024年第6期31卷 141-148页

作者：张志强龚红英周志伟叶恒昌赵江波上海工程技术大学材料工程学院上海201620

进行了常温单向拉伸试验、硬度测试和金相试验,研究了6082铝合金冷塑性变形行为。通过对拉伸后试样的断后伸长率和断面收缩率进行研究发现,随着拉伸速率的增大,两者先增大后减小。通过扫描电镜(SEM)分析,发现6082铝合金的断口形貌呈现... 详细信息

进行了常温单向拉伸试验、硬度测试和金相试验,研究了6082铝合金冷塑性变形行为。通过对拉伸后试样的断后伸长率和断面收缩率进行研究发现,随着拉伸速率的增大,两者先增大后减小。通过扫描电镜(SEM)分析,发现6082铝合金的断口形貌呈现出韧窝-脆面混合断裂的模式,并且在高速拉伸时出现大量破碎的硬脆相。对6082铝合金拉伸试验得到的数据进行分析并建立了优化本构方程,结合有限元数值模拟试验分析,将所建立的优化后的材料本构模型输入有限元软件中进行模拟验证,两者相对误差为1.33%,说明建立的模型可以准确描述6082材料在冷塑性变形状态下的硬化行为。

关键词： 6082铝合金本构模型冷成形有限元单向拉伸

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某全科培训基地首批订单定向住院医师履职后的离职率及其分析

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中国毕业后医学教育 2024年第9期8卷 708-711页

作者：武静张强赵珩王春艳吉林大学第一医院全科医学科吉林长春130021

目的调查吉林大学第一医院全科培训基地首批订单定向住院医师结业履职后的工作现状。方法2021年12月,调查组自行设计问卷调查,应用问卷星对上述人员开展问卷调查,调查内容主要包括一般资料、是否离职或有离职意愿以及工作满意度,并在规... 详细信息

目的调查吉林大学第一医院全科培训基地首批订单定向住院医师结业履职后的工作现状。方法2021年12月,调查组自行设计问卷调查,应用问卷星对上述人员开展问卷调查,调查内容主要包括一般资料、是否离职或有离职意愿以及工作满意度,并在规定时间内回收问卷。结果该院2015级订单定向结业住院医师共40名,参与调查者36名。结业后所调查的全科住院医师全部回到原就职地,但履约期满已离职人员有7人,占19.4%。调查人群离职意愿高,工作满意度低。结论全科订单定向住院医师的高离职率是目前需引起重视和思考的严峻问题。

关键词：订单定向住院医师全科医师离职率

Loess erosion change modeling during heavy rainfall

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International Journal of Sediment Research 2023年第1期38卷 24-32页

作者： Hongwu zhang Guangquan Liu Chensu zhao Luohao zhang qiang zhang heng Fu Shuai Cao Department of Hydraulic Engineering Tsinghua University State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research School of Civil and Environment Engineering University of Science and Technology Beijing Ordos Municipal Water Resources Bureau Ordos Municipal Water Conservancy Development Center

A typical gully sub-basin with a complex geomorphological form is used to do a model test of gravity erosion of loess by considering the sequence of slopes in a prototype gully creating a sequence of underlying surface forms in the upper reaches. The results show that the runoff from heavy rainfall is the main external force for the erosion of loess, and also is an important influencing factor to stimulate and intensify the development of gravity erosion. The soil structure and the height of the critical surface have a direct impact on the possibility of gravity erosion. Spatially, the upper section of the drainage channel mainly experiences undercutting and headcut erosion, the middle section mainly experiences lateral erosion and gravity erosion, and the lower section alternately experiences sedimentation or alluvial erosion. Rainfall splash erosion produces a large amount of sand to yield high concentration mud flows in the middle and lower sections of the channel. Because of the mud flows the flood flow is obviously larger than the runoff volume formed by rainfall in a small watershed. The flood formed by high-intensity rainfall brings a large amount of sediment into the downstream rivers along the channel, indicating that under the condition that high-intensity rainfall on the Loess Plateau, lots sediment will enter the Yellow River, and the erosion deformation occurs on all slopes. Further the steep slope drainage flow causes undercutting and lateral erosion, and the soil body moves down along the slope under the action of gravity. The gully in the middle section still experience sediment washing in both depth and width,and the downstream gully continues to experiences sedimentation due to the reduction of the gradient,reflecting the adaptive adjustment of water flow and the boundary. Headcut erosion occurred on almost all slopes during different periods of rainfall, while gravity erosion mostly occurred on steep slope sections during periods of high-intensity

关键词： Gravity erosion Slope erosion Erosion modeling Heavy rainfall

Polyisoprene Bearing Dual Functionalized Mini-blocky Chain-ends Prepared from Neodymium-mediated Coordinative Chain Transfer Polymerizations

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Chinese Journal of Polymer Science 2023年第5期41卷 720-727,I0008页

作者： Wei-Xin Wang Wen-Peng zhao Jing Dong Hua-qiang zhang Feng Wang heng Liu xue-Quan zhang Key Laboratory of Rubber-Plastics Ministry of EducationShandong Provincial Key Laboratory of Rubber-PlasticsQingdao University of Science&TechnologyQingdao 266042China Petrochemical Research Institute PetroChinaBeijing 102206China School of Chemical Engineering Changchun University of TechnologyChangchun 130012China

Through neodymium-mediated coordinative chain transfer copolymerizaiton(CCTcoP),polyisoprenes bearing dual hydroxylated mini-blocky chain-ends were prepared via a three-step *** studies revealed that,the polymerization demonstrated typical features of CCTcoP across the whole polymerization process,i.e.,quasi-living polymerization characteristic,tunable molecular weights,narrow molecular weight distributions,and atom *** to previously reported CCTP homopolymerization systems,the presence of oxygen-containing IpOAl polar comonomer slowed down chain transfer rates obviously,rendering slightly higher molecular weights of the resultant PIps and smaller Np(number of polymer chains per Nd atom)***,to mimic the structure of natural rubber,the hydroxyl end groups can be facilely modified into phosphonate,amide,and UPy,whose structures were further confirmed by NMR *** these functionalities could greatly improve the hydrophilic properties of the polymers,as revealed from the significantly reduced static water contact angles.

关键词： Functional polyisoprene Neodymium Coordinative chain transfer polymerization Synthetic rubber

Super-exchange effect induced by early 3d metal doping on NiFe_(2)O_(4)(001)surface for oxygen evolution reaction

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Journal of Energy Chemistry 2023年第3期78卷 21-29,I0002页

作者： Shuhao Wang Xinyan Liu Xiang Chen Kamran Dastafkan Zhong-heng Fu Xin Tan qiang zhang Chuan zhao School of Chemistry The University of New South WalesSydneyNSW 2052Australia Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina Integrated Materials Design Laboratory Department of Applied MathematicsResearch School of PhysicsThe Australian National UniversityCanberraACT 2601Australia

Understanding the intrinsic activity of oxygen evolution reaction(OER) is crucial for catalyst *** date,different metal-doping strategies have been developed to achieve this,but the involving mechanisms remain ***,the electronic structure of the transition metal-doped NiFe_(2)O_(4)(001) surface is scrutinized for OER intrinsic activity using density functional theory *** 3d-orbital filling metals(Ti,V,Cr,Mn,and Co) are introduced as dopants onto A-and B-layers of the NiFe_(2)O_(4)(001) surface,and variation of oxidation states over Fe sites is observed on *** the magnetic moment and charge transfer of surface cation sites reveals that the variation of Fe oxidation states originates from the super-exchange effect and is influenced by the t2g-electron configuration of 3d metal *** trend governs the generation of highly-active Fe3+sites on the B-layer,the adsorption strength of OER intermediates,i.e.,*O and*OH,and therefore the intrinsic *** finding of super-exchange mechanism induced by 3d early metal doping offers insights into electronic structure tailoring strategies for improving the intrinsic activity of OER electrocatalysts.

关键词： Oxygen evolution reaction NiFe spinel Oxidation states Super-exchange mechanism Density functional theory

SuperPATH入路髋关节置换术治疗股骨颈骨折的临床疗效

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中国现代手术学杂志 2024年第3期28卷 201-207页

作者：赵婷婷张大伟孙强罗恒邱荣冯翔王倩空军军医大学第一附属医院骨科手术室陕西西安710032 空军军医大学第一附属医院骨科陕西西安710032 空军军医大学第一附属医院外科陕西西安710032

目的探讨SuperPATH入路髋关节置换术治疗股骨颈骨折患者的临床疗效。方法采用回顾性病例对照研究。选取2019年1月~2023年10月在空军军医大学第一附属医院骨科行全髋关节置换术(total hip arthroplasty,THA)的股骨颈骨折患者120例,按照... 详细信息

目的探讨SuperPATH入路髋关节置换术治疗股骨颈骨折患者的临床疗效。方法采用回顾性病例对照研究。选取2019年1月~2023年10月在空军军医大学第一附属医院骨科行全髋关节置换术(total hip arthroplasty,THA)的股骨颈骨折患者120例,按照手术方法分为研究组(n=61例)和对照组(n=59例)。研究组采用SuperPATH入路,对照组采用后外侧入路。比较两组围术期相关指标,术后3 d、术后2周及术后1个月时的疼痛视觉模拟评分(visual analog scale,VAS)、髋关节功能Harris评分,术后1个月时的髋关节活动度,以及并发症发生率。结果围术期相关指标比较,两组手术时间、术中出血量比较均无统计学意义(P>0.05),但研究组切口长度更短,术后下床活动时间及术后住院时间均短于对照组(P0.05)。术后1个月时,研究组髋关节屈曲、外旋、内旋、外展、内收活动度明显大于对照组(P0.05)。结论SuperPATH入路髋关节置换术治疗股骨颈骨折,可改善围手术期各项指标,有效减轻术后疼痛,提高髋关节功能,改善髋关节活动度,值得临床推广应用。

关键词： SuperPATH入路后外侧入路全髋关节置换术股骨颈骨折临床疗效

Geomorphic and tectonic controls of landslides induced by the 2022 Luding earthquake

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Journal of Mountain Science 2022年第12期19卷 3323-3345页

作者： zhao Bo HU Kai-heng YANG Zong-ji LIU Qiao ZOU qiang CHEN Hua-yong zhang Bo zhang Wei-feng ZHU Lei SU Li-jun Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu610041China China-Pakistan Joint Research Center on Earth Sciences Islamabad45320Pakistan University of Chinese Academy of Sciences Beijing100049China

On 05 September 2022,an Ms 6.8(Mw 6.6)earthquake occurred in Luding County,Sichuan Province,China,with the epicenter at 29.59°N,102.08°E and a focal depth of approximately *** field investigations,high-resolution satellite images and multiple datatpes characterizing the seismogenic structure,topography and geology,this study attempts to discuss the influence of geomorphic and tectonic indexes on landslide *** results show that the 2022 Luding earthquake with seismogenic fault at the Moxi fault,was a sinistral strike-slip event that triggered at least 4528landslides over an area of~2000 *** landslides span a total area of 28.1 km^(2),and the western section of the seismogenic fault,which serves as the active wall area,is characterized by a higher landslide concentration,especially in the Wandong *** seismogenic fault and lithology influence the regional distribution of landslides,and more landslides occurred closer to the seismogenic fault and in the controlling lithologies of granite and *** topography influences the landslide occurrence position on the slope;the eastern section is prone to form landslides in the lower gorge section,and the western section is prone to form landslides in the upper-top section of the *** coseismic landslides in the eastern Baryan Har block,the eastern boundary(Longmenshan fault),where the earthquakes are characterized by thrusts with slight dextral strike-slip movement,could be the primary landslide-prone area;the southern boundary,the Moxi fault and the southern segment of the Xianshuihe fault,with more intensive strikeslip movement,may be the secondary landsideprone area;and the northern boundary is the tertiary landside-prone ***,the current landslide inventory may be underestimated although this underestimation has limited influence on the results.

关键词： Landslides Luding earthquake Spatial distribution Geomorphic index Tectonic index

Basement Structure and Properties of the Western Junggar Basin, China

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Journal of Earth Science 2019年第2期30卷 223-235页

作者： junmeng zhao Shuze Chen Gong Deng xuezhong Shao heng zhang Jamshed Aminov Xinfa Chen Zongjin Ma Chinese Academy of Sciences(CAS)Center for Excellence in Tibetan Plateau Earth Sciences Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau ResearchChinese Academy of Sciences University of Chinese Academy of Sciences Institute of Geology China Earthquake Administration Xinjiang Oilfield Company

A comprehensive geophysical profile stretching from Qingyijing at the southern edge of the Junggar Basin to Ubara on the northern margin of the Junggar Basin was conducted in an attempt to probe the crustal structure of the western Junggar Basin(hereafter referred to simply as ‘the Basin'), and, in particular, the structure and property of the Basin's crystalline basement. A survey using seismically converted waves was conducted along this profile to determine the characteristics of the P-and Swave velocities typical of the crust and uppermost mantle. A joint inversion of gravitation and aeromagnetic data was also performed to acquire the density and magnetization intensity values found beneath the western Basin. This research revealed that the Basin is composed of the so-called Manasi terrain in the south, and the Wulungu terrain in the north. Their boundary is located along the WNW-trending Dishuiquan-Sangequan suture, linking the NE-striking Da'erbute suture(DS) in the west, and the WNWtrending Kalameili suture(KS) in the east. In its northern part, the Wulungu-type terrain has a doublelayered basement, of which the upper layer is a folded basement of Hercynian orogenic origin, and the lower layer is a crystalline basement of Middle–Upper Proterozoic age. The southern part of the Basin, i.e., the Manasi terrain, has a single-layered crystalline basement. The folded basement here is too thin to be clearly distinguished.

关键词： Junggar Basin seismically-converted wave joint inversion of gravity and geomagnetism basement structure