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Segmental nature of the Red River fault revealed by seismic anisotropy and geological structures

Science China Earth Sciences 2024年第8期67卷 2423-2443页

作者： Ying LI Yuan gao School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Earthquake Prediction Institute of Earthquake ForecastingChina Earthquake AdministrationBeijing 100036China

As the western boundary of the Sichuan-Yunnan block(SYB),the Red River fault(RRF)is a major fault that controls deep crustal movement and deformation in the southeast margin of the Tibetan Plateau and regulates middle-lower crustal *** data suggest that the RRF is segmented and exhibits distinct variations in seismicity,velocity structure and crustal deformation from north to *** anisotropy reveals a complex pattern of lateral spatial and vertical stratified distributions.(1)From the perspective of crustal stratification,in the upper crust,the fast wave polarization in the north segment of the RRF is complex and possibly influenced by the Sanjiang lateral collision zone and adjacent faults with varying *** fast wave polarization in the middle segment is in the NW-SE direction,indicating a localized area of closed down or locked up with consistent *** in the south segment,it presents a disordered pattern,signifying complex deep tectonics and stress conditions at the wedged intersection *** the middle-lower crust in the north and south segments of the RRF,the azimuthal anisotropy is strong and consistent with the spatial strike of the weak zone characterized by low-velocity and *** suggests a connection between the anisotropy and the material migration.(2)In the whole crustal scale,the fast wave directions in two sides of the RRF are consistent with the NW-SE tectonic *** indicates that the RRF,as a large fault potentially cutting through the whole crust,strongly controls the surrounding media.(3)In the lithospheric scale,the fast wave polarizations are oriented nearly E-W and independent of the fault strike,consistent with the low P-and S-wave velocity structures and positive radial anisotropy in the upper *** fast wave directions could be related to lithospheric olivine deformation and asthenospheric *** paper suggests a decoupling of deformation between the crust and the lithospheri

关键词： Red River fault Seismic anisotropy Geological structures Lithosphere Fault segmentation

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高压瓷绝缘子振动疲劳试验及损伤识别

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高压电器 2017年第10期53卷 7-11,18页

作者：曹枚根高政国张健陈巍曹文典北方工业大学北京100144 北京航空航天大学土木工程系北京100083 山东泰安腾飞电力设计有限公司山东泰安271000 北京璟能电力科技有限公司北京102206

高压瓷绝缘子广泛应用于变电站,抗震性能非常薄弱。通过对3支同型号的支柱绝缘子振动疲劳试验,得到了绝缘子振动频率与加载次数之间的关系。绝缘子在长期循环振动荷载作用下,虽然绝缘子外观检测正常,绝缘子的损伤主要为法兰弯曲刚度的衰... 详细信息

高压瓷绝缘子广泛应用于变电站,抗震性能非常薄弱。通过对3支同型号的支柱绝缘子振动疲劳试验,得到了绝缘子振动频率与加载次数之间的关系。绝缘子在长期循环振动荷载作用下,虽然绝缘子外观检测正常,绝缘子的损伤主要为法兰弯曲刚度的衰减,导致绝缘子各阶振动频率均有不同程度的下降。通过建立绝缘子试验结构体系的有限元模型,拟合了损伤前、后绝缘子振动模态的前2阶频率,得到了绝缘子法兰节点的弯曲刚度系数等参数值。多阶模态拟合识别不仅可以定性描述绝缘子的损伤,还能准确地识别出损伤位置和严重程度。

关键词：绝缘子法兰弯曲刚度振动疲劳损伤识另q

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Effect of mesopore spatial distribution of HZSM-5 catalyst on zinc state and product distribution in 1-hexene aromatization

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Chinese Journal of Chemical Engineering 2024年第3期67卷 16-26页

作者： Chenhao Wei Di gao Guohao Zhang Liang Zhao Jinsen gao Chunming Xu The State Key Lab of Heavy Oil Processing China University of Petroleum(Beijing)Beijing 102249China SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China

1-hexene aromatization is a promising technology to convert excess olefin in fluid catalytic cracking(FCC)gasoline to high-value benzene(B),toluene(T),and ***,the increasing market demand of xylene has put forward higher requirements for new generation of *** increasing xylene yield in 1-hexene aromatization,the effect of mesopore structure and spatial distribution on product distribution and Zn loading was *** with different mesopore spatial distribution were prepared by post-treatment of parent HZSM-5 zeolite,including NaOH treatment,tetra-propylammonium hydroxide(TPAOH)treatment,and *** was found the evenly distributed mesopore mainly prolongs the catalyst lifetime by enhancing diffusion properties but reduces the aromatics selectivity,as a result of damage of micropores close to the catalyst *** the selectivity of high-value xylene can be highly promoted when the mesopore is mainly distributed interior the ***,the state of loaded Zn was also affected by mesopores spatial *** the optimized catalyst,the xylene selectivity was enhanced by 12.4%compared with conventional Zn-loaded parent HZSM-5 catalyst at conversion over 99%.It was attributed to the synergy effect of mesopores spatial distribution and optimized acid *** work reveals the role of mesopores in different spatial positions of 1-hexene aromatization catalysts in the reaction process and the influence on metal distribution,as well as their synergistic effect two on the improvement of xylene selectivity,which can improve our understanding of catalyst pore structure and be helpful for the rational design of high-efficient catalyst.

关键词： 1-Hexene aromatization Alkali treatment Xylene selectivity Mesopores Zinc state

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火电厂悬吊煤斗结构限位铅阻尼器耗能减震问题研究

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工业建筑 2006年第Z1期36卷 203-206页

作者：廖翌棋高政国姚德康北京航空航天大学土木工程系北京100083 华北电力设计院北京100011

对设置铅阻尼器的火电厂悬吊煤斗结构的耗能减震性能进行了研究。首先用解析方法分析了一个双自由度悬吊体—阻尼器结构的地震反应。然后基于地震弹塑性时程计算方法,通过设计具有不同屈服点的双线性屈服模型,分析了设置有铅阻尼器的煤... 详细信息

对设置铅阻尼器的火电厂悬吊煤斗结构的耗能减震性能进行了研究。首先用解析方法分析了一个双自由度悬吊体—阻尼器结构的地震反应。然后基于地震弹塑性时程计算方法,通过设计具有不同屈服点的双线性屈服模型,分析了设置有铅阻尼器的煤斗悬吊结构的地震反应。计算结果表明,铅挤压式阻尼器对控制悬吊煤斗与结构的相对位移、减小火电厂的结构地震反应有显著的效果。

关键词：悬吊煤斗铅挤压式阻尼器耗能减震

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大型火电厂煤斗悬吊结构抗震反应谱分析

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工业建筑 2006年第Z1期36卷 207-209,198页

作者：孟繁飞高政国廖翌棋北京航空航天大学土木工程系北京100083

悬吊结构是一种理论技术成熟的抗震结构形式,将煤斗采用悬吊方式设置以改善电厂厂房结构的抗震性能是一项新的大型火电厂结构措施。利用ANSYS有限元分析软件,用反应谱法分析了丰镇火力发电厂采用煤斗悬吊结构与传统的煤斗支承结构在地... 详细信息

悬吊结构是一种理论技术成熟的抗震结构形式,将煤斗采用悬吊方式设置以改善电厂厂房结构的抗震性能是一项新的大型火电厂结构措施。利用ANSYS有限元分析软件,用反应谱法分析了丰镇火力发电厂采用煤斗悬吊结构与传统的煤斗支承结构在地震作用下的结构反应特点。对比分析表明,煤斗悬吊结构对减小火电厂的结构地震反应有显著的效果。

关键词：悬吊煤斗减震地震反应反应谱

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Impacts of central-Pacific El Niño and physical drivers on eastern Pacific bigeye tuna

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Journal of Oceanology and Limnology 2024年第3期42卷 972-987页

作者： Peng LIAN Le gao Key Laboratory of Ocean Observation and Forecasting and Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

Bigeye tuna Thunnus obesus is an important migratory species that forages deeply,and El Niño events highly influence its distribution in the eastern Pacific *** sea surface temperature is widely recognized as the main factor affecting bigeye tuna(BET)distribution during El Niño events,the roles of different types of El Niño and subsurface oceanic signals,such as ocean heat content and mixed layer depth,remain *** conducted A spatial-temporal analysis to investigate the relationship among BET distribution,El Niño events,and the underlying oceanic signals to address this knowledge *** used monthly purse seine fisheries data of BET in the eastern tropical Pacific Ocean(ETPO)from 1994 to 2012 and extracted the central-Pacific El Niño(CPEN)indices based on Niño 3 and Niño ***,we employed Explainable Artificial Intelligence(XAI)models to identify the main patterns and feature importance of the six environmental variables and used information flow analysis to determine the causality between the selected factors and BET ***,we analyzed Argo datasets to calculate the vertical,horizontal,and zonal mean temperature differences during CPEN and normal years to clarify the oceanic thermodynamic structure differences between the two types of *** findings reveal that BET distribution during the CPEN years is mainly driven by advection feedback of subsurface warmer thermal signals and vertically warmer habitats in the CPEN domain area,especially in high-yield fishing *** high frequency of CPEN events will likely lead to the westward shift of fisheries centers.

关键词： bigeye tuna central-Pacific El Niño(CPEN) ocean heat content Argo explainable artificial intelligence(XAI) information flow

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The late Early-Paleozoic granitic magmatism in Northwestern Fujian, China: constraints on intraplate orogeny in the South China block

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Acta Geochimica 2024年第1期43卷 134-149页

作者： WanLi gao ZongXiu Wang Institute of Geomechanics Chinese Academy of Geological ScienceBeijing 100081People’s Republic of China Key Laboratory of Paleomagnetism and Tectonic Reconstruction of Ministry of Natural Resources Beijing 100081People’s Republic of China

The Early Paleozoic tectono-thermal event was a significant orogenic activity during the Phanerozoic era,which had a profound impact on the early crust of the South China Block(SCB) and established the foundation for later tectonic *** Wuyi-Yunkai orogenic belt in Southeastern China was extensively exposed to Early Paleozoic magmatism,the genetic mechanism of which remains *** shed light on this issue,detailed petrological,geochemical,and zircon U-Pb-Hf isotopic studies were carried out on two granitoids,namely the Yuntongshan pluton and the gaoqiao pluton,identified in the central *** U-Pb chronology of the Yuntongshan and gaoqiao bodies yielded ages of437±4 Ma(MSWD=2.2) and 404±2 Ma(MSWD=12),respectively,indicating that they were emplaced during the Early Silurian and Early Devonian *** granitoids are primarily composed of biotite-granite and biotite-monzonitic-granites,with high concentrations of S_(i)O_(2)(73.59-75.91 wt%),K_(2)O+Na_(2)O(8.31-8.73wt%),and low contents of MgO,CaO,Cr,*** are classified as high-K calc-alkaline and weakly metaluminous-strongly peraluminous S-type *** granitoids are enriched in light rare earth elements(LREEs) and large ion lithophile elements(LILEs) and depleted in heavy rare earth elements(HREEs) and high field strength elements(HFSEs) with arc *** εHf(t) values of-3.3 to-15.4 with two-stage Hf model ages ranging from 2829 to 1644 Ma,combined with the presence of Neoproterozoic inherited zircons,suggest that the primary magma of these granitoids was derived from the partial melting of Neoproterozoic crust with a Paleoproterozoic crustal model *** findings,combined with the spatio-temporal distribution of regional magmatism,reveal that the late Early-Paleozoic granitoids formed in the intraplate orogenic background originating from the subduction of the proto-Tethys Ocean and proto-Pacific Ocean around the margin of the east Gondwana supercontinent.

关键词： Late Early-Paleozoic Granites Intraplate orogeny Cathysian block Zircon U-Pb-Hf Isotopic composition

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A novel relationship between elastic modulus and void ratio associated with principal stress for coral calcareous sand

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1033-1048页

作者： Ran gao Jianhong Ye State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

Elastic moduli,*** modulus G and bulk modulus K,are important parameters of geotechnical materials,which are not only the indices for the evaluation of the deformation ability of soils but also the important basic parameters for the development of the constitutive models of geotechnical *** this study,a series of triaxial loading-unloading-reloading shear tests and isotropic loading-unloadingreloading tests are conducted to study several typical mechanical properties of coral calcareous sand(CCS),and the void ratio evolution during loading,unloading and *** test results show that the stress-strain curves during multiple unloading processes are almost parallel,and their slopes are much greater than the deformation modulus at the initial stage of *** relationship between the confining pressure and the volumetric strain can be defined approximately by a hyperbolic equation under the condition of monotonic loading of confining *** the condition of confining pressure unloading,the evolution of void ratio is linear in the e-lnp0 plane,and these lines are a series of almost parallel lines if there are multiple processes of *** on the experimental results,it is found that the modified Hardin formulae for the elastic modulus estimation have a significant deviation from the tested values for *** on the experimental results,it is proposed that the elastic modulus of soils should be determined by the intersection line of two spatial surfaces in the G/K-e-p’/pa space(pa:atmosphere pressure).“Ye formulation”is further proposed for the estimation of the elastic modulus of *** new estimation formulation for soil elastic modulus would provide a new method to accurately describe the mechanical behavior of granular soils.

关键词： Coral calcareous sand(CCS) Elastic shear modulus Elastic bulk modulus Triaxial test Estimation formulation Ye formulation

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一种滞弹簧耗能的新型离散元滚动阻力模型研究

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力学学报 2021年第9期53卷 2384-2394页

作者：高政国董朋昆张雅俊孙卉竹迪亚北京航空航天大学交通科学与工程学院北京100191 中国矿业大学(北京)力学与建筑工程学院北京100083

颗粒间滚动阻力对颗粒体系的稳定性起着重要作用.在传统的离散元法中,滚动阻力模型通常由转动弹簧、转动黏壶和摩擦元件表达,颗粒滚动动能由黏滞力(矩)和摩擦力做功耗散.由于黏滞力(矩)与滚动速度相关,临近静止状态的颗粒滚动速度变小,... 详细信息

颗粒间滚动阻力对颗粒体系的稳定性起着重要作用.在传统的离散元法中,滚动阻力模型通常由转动弹簧、转动黏壶和摩擦元件表达,颗粒滚动动能由黏滞力(矩)和摩擦力做功耗散.由于黏滞力(矩)与滚动速度相关,临近静止状态的颗粒滚动速度变小,动能耗散减弱,传统的离散元模拟得到颗粒由滚动到静止耗费的时间比试验观测的结果要长.为解决这一问题,基于摩擦学理论分析了滚动阻力产生的材料滞弹性机理,将其引入离散元滚动阻力模型,提出了一种速度无关型动能耗散的滞弹簧,给出了滞弹簧的弹性恢复力计算公式,建立了一种新型的离散元滞弹性滚动阻力模型(HDEM).为验证新型滚动阻力模型的正确性,通过一个光学物理试验对单个圆形颗粒试件的自由滚动过程进行了测量,将测量数据与新型的滞弹型离散元模型和传统离散元模型计算结果进行了对比.结果显示,基于滞弹性滚动阻力模型HDEM计算结果与试验数据吻合程度更高,而且模拟得到的颗粒摆动频率更符合试验现象.

关键词：滚动阻力颗粒体系离散元模型弹性滞后滞弹簧

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A novel cascaded H-bridge photovoltaic inverter with flexible arc suppression function

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Global Energy Interconnection 2024年第4期7卷 513-527页

作者： Junyi Tang Wei gao College of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108P.R.China

This paper presents a novel approach that simultaneously enables photovoltaic(PV)inversion and flexible arc suppression during single-phase grounding *** compensate for ground currents through an arc-elimination function,while outputting a PV direct current(DC)power *** method effectively reduces the residual grounding *** reduce the dependence of the arc-suppression performance on accurate compensation current-injection models,an adaptive fuzzy neural network imitating a sliding mode controller was *** online adaptive adjustment law for network parameters was developed,based on the Lyapunov stability theorem,to improve the robustness of the inverter to fault and connection ***,a new arc-suppression control exit strategy is proposed to allow a zerosequence voltage amplitude to quickly and smoothly track a target value by controlling the nonlinear decrease in current and reducing the regulation *** results showed that the proposed method can effectively achieve fast arc suppression and reduce the fault impact current in single-phase grounding *** to other methods,the proposed method can generate a lower residual grounding current and maintain good arc-suppression performance under different transition resistances and fault locations.

关键词： Photovoltaic inverter Flexible arc suppression Adaptive control Fuzzy neural network Sliding mode control Exit strategy

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