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贵州织金寒武系戈仲伍组钉形类骨片化石研究

古生物学报 2024年第2期63卷 155-170页

作者：朱万林杨兴莲贵州大学资源与环境工程学院贵州省古生物研究中心贵阳550025 喀斯特地质资源与环境教育部重点实验室(贵州大学) 贵阳550025

钉形类(nail-shaped)骨片化石是华南寒武纪早期地层中常见的一类具矿化骨骼的小壳化石。本文系统研究了贵州织金戈仲伍剖面寒武系戈仲伍组的钉形类骨片化石,发现织金地区钉形类化石主要以织金钉类和疑似的寒武钉类为主,共4属9种。相较... 详细信息

钉形类(nail-shaped)骨片化石是华南寒武纪早期地层中常见的一类具矿化骨骼的小壳化石。本文系统研究了贵州织金戈仲伍剖面寒武系戈仲伍组的钉形类骨片化石,发现织金地区钉形类化石主要以织金钉类和疑似的寒武钉类为主,共4属9种。相较于前人研究,本文新发现了织金钉类:Zhijinites tumourifomis、***、***,和疑似的寒武钉类:?Deiradoclavus sp.、?Cambroclavus sp.。排除埋藏学假象后,分析了钉形类不同化石属种保存方式及形态结构,发现Zhijinites的多数种都存在盘体顶面凹陷结构,并且Zhijinites部分种的锥体内壁有收缩现象或具有十字交错纤维结构,这些发现能较好地揭示出Zhijinites各形态种间的相似性和差异性。分析钉形化石时空分布特点发现,目前钉形类骨片化石最早在织金地区有化石记录,之后在扬子地台内部辐射扩散,并几乎同时辐射扩散至邻近陆块。此外,本文讨论的疑似寒武钉类化石时代可下延至寒武纪幸运期,可能是目前该类化石在全球的最早记录,为探索寒武钉类化石的系统演化和地层学意义提供了新信息。

关键词：小壳化石织金钉类寒武钉类戈仲伍组寒武系贵州

基于现场监测与数值模拟结合的采动诱发围岩失稳与地表沉降研究

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东北大学学报（自然科学版） 2024年第2期45卷 234-243页

作者：王雨萌关凯朱万成刘洪磊东北大学资源与土木工程学院辽宁沈阳110819

基于3Dmine与无人机倾斜摄影技术建立集成真实地表地貌、矿体及巷道的三维地质模型,结合Rhino6-FLAC3D建立矿体回采数值计算模型,对浅部岩层移动和地表变形的影响进行模拟分析,结合InSAR地表变形监测数据对模拟结果的有效性进行对比验... 详细信息

基于3Dmine与无人机倾斜摄影技术建立集成真实地表地貌、矿体及巷道的三维地质模型,结合Rhino6-FLAC3D建立矿体回采数值计算模型,对浅部岩层移动和地表变形的影响进行模拟分析,结合InSAR地表变形监测数据对模拟结果的有效性进行对比验证。结果表明:模拟结果与InSAR地表变形监测数据具有较好的一致性,表明基于多手段的数值建模计算与现场监测数据相结合的分析方法的有效性;对空场采矿法残留的采空区采用废石充填能够在有效控制空区围岩塑性区发展基础上维持充填体稳定性;矿区深部矿体的回采与充填可能对浅部已充填采场围岩的稳定性产生一定影响,浅部已充填采场受扰动严重程度与深部作业区域距离呈负相关;由InSAR监测数据和数值模拟结果可知,深部矿体回采扰动和浅部空区二次破坏对地表沉降影响较小.

关键词：地表变形采空区数值模拟充填体 InSAR监测

Linear dichroism transition and polarization-sensitive photodetector of quasi-one-dimensional palladium bromide

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Chinese Physics B 2024年第6期33卷 532-539页

作者：朱万里甄伟立牛瑞焦珂珂岳智来胡慧杰薛飞张昌锦 Anhui Key Laboratory of Low-energy Quantum Materials and Devices High Magnetic Field LaboratoryHFIPSChinese Academy of SciencesHefei 230031China Science Island Branch Graduate School of University of Science and Technology of ChinaHefei 230026China School of Physics Hefei University of TechnologyHefei 230601China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

Perpendicular optical reversal of the linear dichroism transition has promising applications in polarization-sensitive optoelectronic devices. We perform a systematical study on the in-plane optical anisotropy of quasi-one-dimensional PdBr_(2) by using combined measurements of the angle-resolved polarized Raman spectroscopy(ARPRS) and anisotropic optical absorption spectrum. The analyses of ARPRS data validate the anisotropic Raman properties of the PdBr_(2) *** anisotropic optical absorption spectrum of PdBr_(2) nanoflake demonstrates distinct optical linear dichroism reversal. Photodetector constructed by PdBr_(2) nanowire exhibits high responsivity of 747 A·W^(-1) and specific detectivity of 5.8×10^(12) Jones. And the photodetector demonstrates prominent polarization-sensitive photoresponsivity under 405-nm light irradiation with large photocurrent anisotropy ratio of 1.56, which is superior to those of most of previously reported quasi-one-dimensional counterparts. Our study offers fundamental insights into the strong optical anisotropy exhibited by PdBr_(2), establishing it as a promising candidate for miniaturization and integration trends of polarization-related applications.

关键词： linear dichroism reversal polarization sensitivity anisotropy polarized photodetector

Chinese Continental Blocks in Global Paleocontinental Reconstruction during Paleozoic and Mesozoic

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Acta Geologica Sinica(English Edition) 2011年第3期85卷 581-597页

作者： wan Tianfeng zhu Hong School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China

The Cambrian to Cretaceous paleomagnetic data from Chinese continental and adjacent blocks were collected using principles to obtain reliable and high-precision paleomagnetic data and to pay attention to the similarity of paleobiogeography and the coordination of tectonic *** Chinese continental blocks were laid up on the reconstruction of proposed global paleocontinents with almost the same ***,it can be clearly recognized that the global continents,including Chinese continental blocks,range along latitudes on the southern side of the equator during the Early Paleozoic. In the Paleozoic,Chinese continental blocks were still located among the Laurentia,Siberia and Gondwana plates,following the fast moving of the Siberia Plate northwards,the amalgamation in a north-south direction at the western parts of the Laurentia and Gondwana plates,and the Iapetus and Rheic Oceans were subducted,eventually to form a uniform Pangea in the Late *** Australian and Indian plates of Eastern Gondwana moved and dispersed gradually southwards, continued to extend the Paleo-Tethys *** Chinese continental and adjacent blocks were still located in the Paleo-Tethys Ocean,preserved the status of dispersion,gradually moving northwards, showing characteristics of ranging along a north-south orientation until the *** addition,a series of local collisions happened during the Triassic,and consequently most of the Chinese continental blocks were amalgamated into the Pangea,except for the Gangdise and Himalayan blocks. There was a counter-clockwise rotation of the Eastern Asian continent in the Jurassic and northwards migration of the Chinese continent in varying degrees during the Cretaceous,but the Himalayan and Indian plates did not collide into the Chinese continent during this period.

关键词： paleomagnetism paleogeographic reconstruction Paleozoic Mesozoic China

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基于轻量语义分割网络的遥感土地覆盖分类

计算机系统应用 2024年第2期33卷 134-142页

作者：朱婉玲贾渊西南科技大学计算机科学与技术学院绵阳621010

高分辨率遥感图像有丰富的空间特征,针对遥感土地覆盖方法中模型复杂,边界模糊和多尺度分割等问题,提出了一种基于边界与多尺度信息的轻量化语义分割网络.首先,使用轻量化的MobileNetV3分类器,采用深度可分离卷积来减少计算量.其次,使... 详细信息

高分辨率遥感图像有丰富的空间特征,针对遥感土地覆盖方法中模型复杂,边界模糊和多尺度分割等问题,提出了一种基于边界与多尺度信息的轻量化语义分割网络.首先,使用轻量化的MobileNetV3分类器,采用深度可分离卷积来减少计算量.其次,使用自顶向下和自底向上的特征金字塔结构来进行多尺度分割.接着,设计了一个边界增强模块,为分割任务提供丰富的边界细节信息.然后,设计了一个特征融合模块,融合边界与多尺度语义特征.最后,使用交叉熵损失函数和Dice损失函数来处理样本不平衡的问题.在WHDLD数据集的平均交并比达到了59.64%,总体精度达到了87.68%.在DeepGlobe数据集的平均交并比达到了70.42%,总体精度达到了88.81%.实验结果表明,该模型能快速有效地实现遥感图像土地覆盖分类.

关键词：高分辨率遥感图像土地覆盖分类轻量化语义分割多尺度边界增强卷积神经网络

An advanced higher-order theory for laminated composite plates with general lamination angles

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Acta Mechanica Sinica 2011年第5期27卷 720-729页

作者： Zhen Wu Hong zhu wan-Ji Chen Key Laboratory of Liaoning Province forComposite Structural Analysis of Aerocraft and Simulation Shenyang Aerospace University 110136 Shenyang China

This paper proposes a higher-order shear deformation theory to predict the bending response of the laminated composite and sandwich plates with general lamination *** proposed theory a priori satisfies the continuity conditions of transverse shear stresses at ***,the number of unknown variables is independent of the number of *** first derivatives of transverse displacements have been taken out from the inplane displacement fields,so that the C 0 shape functions are only required during its finite element *** to C 0 continuity requirements,the proposed model can be conveniently extended for implementation in commercial finite element *** verify the proposed theory,the fournode C 0 quadrilateral element is employed for the interpolation of all the displacement parameters defined at each nodal point on the composite *** results show that following the proposed theory,simple C 0 finite elements could accurately predict the interlaminar stresses of laminated composite and sandwich plates directly from a constitutive equation,which has caused difficulty for the other global higher order theories.

关键词： Laminated and sandwich composites Higherorder theory C 0 continuity requirement Transverse shear stress

国际视野下职业教育数字化教学创新研究——以2023年欧洲创新教学奖职业教育类奖项为例

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天津中德应用技术大学学报 2024年第4期 44-51页

作者：朱婉莹毛文祺湖南科技职业学院湖南长沙418000

通过研究分析2023年欧洲创新教育奖27个职业教育类别项目,发现获奖项目的主题创新点主要集中在:注重跨国资源协作共享,凸显数字化工具的应用,跟进企业最新数字技术与需求。数字技术赋能下,欧洲职业教育创新教学奖所体现的教学创新具体... 详细信息

通过研究分析2023年欧洲创新教育奖27个职业教育类别项目,发现获奖项目的主题创新点主要集中在:注重跨国资源协作共享,凸显数字化工具的应用,跟进企业最新数字技术与需求。数字技术赋能下,欧洲职业教育创新教学奖所体现的教学创新具体表现在:教师角色注重数字协作与国际团队合作,教学方法多采用混合教学模式与个性化学习路径,教学环境的虚拟化与开放资源共享,教学成果注重多样评估体系与全纳教育实践。根据欧洲职业教育教师创新教学实践经验,提出我国数字时代下促进职业教育创新教学实践的建议:构建教学团队,注重跨领域合作与虚拟团队的建设;支持教师终身职业发展,优化数字资源,提供广泛的发展机会;关注学生个体成长需求,实行精准教学与全面融合教育;提升教学影响力,搭建支持系统与利用国际化平台。

关键词：数字时代职业教育教师创新教学教学实践

Electromigration in eutectic SnAg solder reaction couples with various ambient temperatures and current densities

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International Journal of Minerals,Metallurgy and Materials 2009年第6期16卷 685-690页

作者： Guang-chen Xu Fu Guo wan-rong zhu College of Materials Science and Engineering Beijing University of Technology Beijing 100124 China

The electromigration behavior of eutectic SnAg solder reaction couples was studied at various temperature （25 and 120℃ when the current density was held constant at 104 A/cm^2 or 5×10^3 A/cm^2. Under the current density of 104 A/cm^2, scallop type Cu6Sn5 spalls and migrates towards the direction of electron flow at room ambient temperature （25℃）, but transforms to layer type Cu3Sn and leaves Kirkendall voids in it at high ambient temperature （120℃）. Under the current density of 5×10^3 A/cm^2 plus room ambient temperature, no obvious directional migration of metal atoms/ions is found. Instead, the thermal stress induced by mismatch of dissimilar materials causes the formation of superficial valley at both interfaces. However, when the ambient temperature increases to 120℃, the mobility of metal atoms/ions is enhanced, and then the grains rotate due to the anisotropic property of β-Sn.

关键词： electromigration eutectic solder Joule heating intermetallic compound

Modified Frequency Scaling Algorithm for FMCW SAR Data Processing

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Chinese Journal of Aeronautics 2007年第4期20卷 339-345页

作者： Jiang Zhihong Huang Fukan wan Jianwei Cheng zhu College of Electronic Science and Engineering National University of Defense Technology Changsha 410073 China

This paper presents a modified frequency scaling algorithm for frequency modulated continuous wave synthetic aperture radar （FMCW SAR） data processing. The relative motion between radar and target in FMCW SAR during reception and between transmission and reception will introduce serious dilation in the received signal. The dilation can cause serious distortions in the reconstructed images using conventional signal processing methods. The received signal is derived and the received signal in range-Doppler domain is given. The relation between the phase resulting from antenna motion and the azimuth frequency is analyzed. The modified frequency scaling algorithm is proposed to process the received signal with serious dilation. The algorithm can effectively eliminate the impact of the dilation. The algorithm performances are shown by the simulation results.

关键词： FMCW radar SAR radar imaging frequency scaling algorithm