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基岩地质差异对活动断层地表几何形态的控制作用——以祁连山北缘佛洞庙-红崖子断层为例

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地质力学学报 2024年第2期30卷 348-362页

作者：杨勇忠李占飞任俊杰徐锡伟李康程佳康文君中国科学院大学应急管理科学与工程学院北京101408 应急管理部国家自然灾害防治研究院北京100085 中国地质大学(北京)地球科学与资源学院北京100083

全球广泛分布的活动断层是孕育地表破裂型强震的天然载体,地球科学观测揭示活动断层的先存几何结构对地震地表破裂的发育演化具有很强的控制作用。目前针对活动断层地表构造变形特征与基岩地质背景关系的研究较少且仅局限于高温高压岩... 详细信息

全球广泛分布的活动断层是孕育地表破裂型强震的天然载体,地球科学观测揭示活动断层的先存几何结构对地震地表破裂的发育演化具有很强的控制作用。目前针对活动断层地表构造变形特征与基岩地质背景关系的研究较少且仅局限于高温高压岩石力学实验尺度,缺乏数百千米尺度天然活动断层结构特征的直接参考,尤其是关于活动逆冲断层的研究相对更少。不断发展的高精度对地观测技术和活动构造定量研究方法能够更加精细地刻画活动断层大尺度几何结构,清晰揭示断层多参数错断地貌特征,深化断层活动行为的定量研究。利用青藏高原东北缘佛洞庙-红崖子逆冲断层上长约120 km的高精度地形数据(分辨率为0.5 m),系统分析了该断层浅表错断地貌参数特征,并将其与基岩地质背景进行综合对比。研究结果揭示出断层上断错地貌参数显著变化区与断层上盘沿走向的基岩地质界限、断层分段位置以及垂直位移显著衰减区明显对应。对比断层东段和西段,佛洞庙-红崖子断层中段志留系花岗岩发育区几何结构更加粗糙且浅表变形带宽度更大,断层阶跃宽度分布沿断层的变化也更为剧烈。研究结果进一步提示基岩地质背景对逆冲断层的浅表构造变形具有很强的控制作用,在活动断层地震危险性分析中也需要关注基础地质背景可能带来的影响。

关键词：活动断层错断地貌基岩地质构造变形

Cenozoic Denudation and Vertical Faulting History of the Central Segment of the Longmenshan Thrust Belt

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Acta Geologica Sinica(English Edition) 2016年第4期90卷 1541-1542页

作者： TAN Xibin XU Xiwei LEE Yuanhsi kang wenjun ZHAO Shiliang Key Laboratory of Active Fault and Volcano Institute of GeologyChina Earthquake Administration Department of Earth and Environmental Sciences National Chung-Cheng University

Objective The uplift process and uplift mechanism of the Tibetan Plateau has been a research focus among geologists in recent years. This work put emphasis on the Cenozoic exhumation histories of the blocks bounded by the major faults at the central segment of the Longmenshan thrust belt, and the vertical faulting history, including the starting time and the total vertical displacement, of the major faults. Then we quantitatively established a complete active process for the central segment of the Longmenshan thrust belt, combining with the previous geophysical data in the deep and geologcial data. This study is critical for deeply and completely understanding the Cenozoic uplift history of the Longmenshan, and also provides thermochronology constraints to the different models for the uplift of the eastern margin of the Tibetan Plateau.

关键词： Cenozoic Denudation and Vertical Faulting History of the Central Segment of the Longmenshan Thrust Belt

Research on Optimization Analysis Method of Exhaust System under Multiple Loading Conditions

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Research on Optimization Analysis Method of Exhaust System u...

新生逆冲断裂地表垂直位错分布与断层活动性关系:以河西走廊临泽断裂为例

2019中国汽车工程学会年会

作者： Qiao Yan Qu Xintian Yu Guiqi Zhan Shuangxi kang wenjun Dongfeng Motor Company Technology Center

The exhaust system is connected to the engine and mounted on the body-in-white with lifting lugs and *** vibration of the engine can be transmitted to the exhaust system through the bellows,which affects the NVH performance of the *** design of the vibration isolation,the stiffness of the lifting lugs,the strength and other performance parameters should be taken into *** exhaust system has many variable parameters,including the stiffness of the bushing,the shape of structure,the thickness of the exhaust pipes,and so *** is difficult to find the optimal parameters of the exhaust system based on conventional *** order to solve the problem,In order to solve the problem,the HyperWorks software was used to simulate the exhaust *** HyperStudy,the DOE design method is used to create a response fitting approximate model,and the optimal solution is obtained by genetic *** in the finite element model of the exhaust system,the size and shape optimization design were carried out to obtain the global optimal *** results revealed that this analytical method is practical and suggestive for multi-objective optimization analysis of exhaust system.

关键词： exhaust system multiple loading conditions optimal parameters DOE fitting model optimization

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地球科学 2022年第3期47卷 831-843页

作者：李占飞徐锡伟任俊杰李康康文君应急管理部国家自然灾害防治研究院北京100085 北京市地震局北京100080 中国地震局地质研究所北京100029

活动断裂地表位错定量研究对理解断裂活动习性和构建多周期地震复发模型有重要意义.前人基于高精度地形数据对断裂地表位错分布开展了大量定量研究,但是关于累积位错变形沿新生逆冲断层的走向分布特征依然不清楚.本文选择河西走廊内部... 详细信息

活动断裂地表位错定量研究对理解断裂活动习性和构建多周期地震复发模型有重要意义.前人基于高精度地形数据对断裂地表位错分布开展了大量定量研究,但是关于累积位错变形沿新生逆冲断层的走向分布特征依然不清楚.本文选择河西走廊内部新生临泽逆冲断裂(<20 ka)为例,利用UAV(unmanned aerial vehicle)航测方法采集了断裂沿线约8 km长、2.5 km宽的高精度(0.5 m)地形数据,开展了精细地貌填图(1∶500)、断层垂直位错测量(73个)、断层活动定量参数分析以及野外地质调查等工作.研究揭示,新生临泽逆冲断裂主要由2条左阶展布分支逆冲断层组成(L1和L2),阶区宽度约260 m.位错测量揭示,断层最大和最小累积位错分别为4.5 m和0.2 m,累积垂直位错呈明显不对称三角形分布,断层上位移亏损点与断层几何形态变化区域明显对应.断裂位错定量参数分析显示,临泽断裂结构不成熟,两个分支断裂后期会在破裂长度和位错增加下逐渐贯通.因此,可能需要注意后期强震活动造成新生逆冲断层向盆地内部拓展,及其对邻近城镇带来的直接和衍生灾害效应.

关键词：新生逆冲断裂垂直位错分布结构成熟度断层拓展地震学

TEMPERED BAINITE EMBRITTLEMENT IN SOME STRUCTURAL STEELS

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Acta Metallurgica Sinica(English Letters) 1989年第5期2卷 337-342页

作者： HU Guangli LIU Zhengtang WANG Ping HUA wenjun kang Mokuang Northwestern Polytechnical University,Xi’an,China HU Guangli,Associate Professor,Department of Materials Science and Engineering,Northwestern Polytechnical University,Xi’an,China

The variations of microstructures and mechanical properties of steels 15CrMnMoV, 18Mn2CrMoB,18Cr2Ni4W,30CrMnSi,30CrMnSiNi2 and 40CrMnSiMoV,which were tempered at different temperatures after austempering and continuous cooling at given rates, have been *** on the experimental results,the behaviour and mechanism of tempered bainite embrittlement(TBE)have been ***,the theoretical and prac- tical basis for selecting the optimum tempering temperature of steels with bainite structure af- ter heat treatment are proposed.

关键词： austempering tempered bainite embrittlememt mechanical stability

Prescribed time control based on the periodic delayed sliding mode surface without singularities

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Science China(Information Sciences) 2024年第7期67卷 256-270页

作者： Bin ZHOU Yi DING kang-kang ZHANG Guang-Ren DUAN Center for Control Theory and Guidance Technology Harbin Institute of Technology

In this paper, nonsingular prescribed-time control is studied based on periodic delayed sliding mode surfaces. Different from the existing sliding mode control, where either singularity problems may appear or the convergence time depends on the initial state, the proposed sliding mode control approaches can achieve prescribed-time convergence without singularity. The proposed nonsingular sliding mode control approaches can be applied to both second-order and high-order nonlinear systems with prescribed-time convergence. As applications of the proposed sliding mode control approaches, the control of hypersonic vehicle systems is revisited. Numerical simulations on the nonlinear model of the hypersonic vehicle system show the effectiveness of the proposed methods.

关键词： prescribed-time control smooth periodic delayed feedback sliding mode control high-order nonlinear systems hypersonic vehicle systems

Progress in the application of polymer fibers in solid electrolytes for lithium metal batteries

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Journal of Energy Chemistry 2024年第5期92卷 26-42页

作者： Junbao kang Nanping Deng Bowen Cheng Weimin kang State Key Laboratory of Separation Membranes and Membrane Processes/National Center for International Joint Research on Separation Membranes School of Textile Science and EngineeringTiangong UniversityTianjin 300387China

Solid state lithium metal batteries(SSLMBs)are considered to be one of the most promising battery systems for achieving high energy density and excellent safety for energy storage in the ***,current existed solid-state electrolytes(SSEs)are still difficult to meet the practical application requirements of *** this review,based on the analysis of main problems and challenges faced by the development of SSEs,the ingenious application and latest progresses including specific suggestions of various polymer fibers and their membrane products in solving these issues are emphatically ***,the inherent defects of inorganic and organic electrolytes are pointed ***,the application strategies of polymer fibers/fiber membranes in strengthening strength,reducing thickness,enhancing thermal stability,increasing the film formability,improving ion conductivity and optimizing interface stability are discussed in detail from two aspects of improving physical structure properties and electrochemical ***,the researches and development trends of the intelligent applications of high-performance polymer fibers in SSEs is *** review intends to provide timely and important guidance for the design and development of polymer fiber composite SSEs for SSLMBs.

关键词： Composite solide lectrolytes Polymer fibers Solid-state lithium metal batteries Solid-stateel ectrolytes Nanofiber membranes

基于综合评价体系的五轴数控机床加工性能评价和误差溯源方法

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机械工程学报 2017年第21期53卷 149-157页

作者：王伟李晴朝康文俊陶文坚杜丽电子科技大学机械电子工程学院成都611731

五轴数控机床的加工性能在制造行业一直是研究的热点,基于检验试件切削是常见的测评方法,然而试件和机床之间的映射关系难以确定,出现误差后如何调整精度成为难点。为了科学对其评价,通过仿真平台建立了机床控制系统参数与五轴机床检验... 详细信息

五轴数控机床的加工性能在制造行业一直是研究的热点,基于检验试件切削是常见的测评方法,然而试件和机床之间的映射关系难以确定,出现误差后如何调整精度成为难点。为了科学对其评价,通过仿真平台建立了机床控制系统参数与五轴机床检验试件——S试件加工误差之间的映射关系,引入机床各轴分类评价的隶属度,此基础上开发了误差溯源的综合评价体系,由三坐标测量机得到的S件轮廓误差数据反求出机床的加工性能等级和较差的轴类控制参数,并制订了基于S试件的机床加工精度测评规范,最后通过某五轴AB摆数控机床的切削试验,验证了方法的有效性。该成果有助于解决我国高端制造业长期缺乏机床性能测评的共性技术问题,具有重要的应用前景和经济价值。

关键词：五轴数控机床 S形检验试件模糊综合评价映射关系误差溯源

Regulation of insect behavior by non-coding RNAs

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Science China(Life Sciences) 2024年第6期67卷 1106-1118页

作者： Jing He Le kang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China Beijing Institutes of Life Sciences Chinese Academy of SciencesBeijing 100101China College of Life Science Hebei UniversityBaoding 071002China

The adaptation of insects to environments relies on a sophisticated set of behaviors controlled by molecular and physiological *** the past several decades,accumulating studies have unveiled the roles of non-coding RNAs(nc RNAs)in regulating insect *** RNAs assume particularly pivotal roles in the behavioral plasticity of insects by rapidly responding to environmental *** RNAs also contribute to the maintenance of homeostasis of insects by fine-tuning the expression of target ***,a comprehensive review of nc RNAs'roles in regulating insect behaviors has yet to be ***,we present the recent progress in our understanding of how nc RNAs regulate various insect behaviors,including flight and movement,social behavior,reproduction,learning and memory,and *** refine the intricate mechanisms by which nc RNAs modulate the function of neural,motor,reproductive,and other physiological systems,as well as gene expression in insects like fruit flies,social insects,locusts,and ***,we discuss potential avenues for future studies in nc RNA-mediated insect behaviors.

关键词： ncRNAs insect behavior plasticity fine-tuning environmental adaptation