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Geophysical constraints on mesozoic disruption of North China Craton by underplating-triggered lower-crust flow of the Archaean lithosphere

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Geophysical constraints on mesozoic disruption of North Chin...

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： Zhongjie Zhang Yanghua Wang Yangfan Deng Lin Chen Jing Wu Jiwen Teng Yun Chen weiming fan Giuliano Panza State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Department of Earth Science and Engineering Imperial College LondonSouth Kensington Campus Guangzhou Institute of Geochemistry Chinese Academy of Sciences State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences Department of Mathematics and Geosciences University of Trieste Institute of Geophysics China Earthquake Administration

The mechanism of the disruption,both lithospheric thinning and oceanization of the commonly accepted long-term-stable Archaean craton,is still an open *** available models,all imply a bottom to top *** the construction of a 1660-km-long transect across the eastern North China Craton(NCC),we demonstrate that both the P-wave velocity and density in the lowermost crust beneath the central section are significantly higher than in the corresponding parts of the south and north sections on the *** features are interpreted as geophysical signature of lower crustal underplating, which supplies sufficiently high gravitational potential energy tO trigger lateral flow of the lower *** magma underplating-triggered bilateral lower crust flow may facilitate the lithospheric thinning by means of asthenosphere upwelling and decompression melting,which infill the gap produced by the lower crust *** underplating-triggered lower crustal flow can provide an alternative mechanism to explain the NCC lithosphere disruption,which highlights the crustal feedback to Archaean lithosphere disruption,from top to bottom.

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浙江浦江晚中生代埃达克质火山岩的成因

岩石学报 2006年第9期22卷 2305-2314页

作者：秦社彩范蔚茗郭锋李超文高晓峰中国科学院广州地球化学研究所边缘海地质重点实验室

浙江浦江地区白垩纪劳村组存在一套独特的中酸性火山岩,其主量元素表现出富 Al_2O_3(>16%)和 Na_2O(4.01%～4.52%),高 Na_2O/K_2O(1.94～5.51,平均2.89),高 Sr(583～643μg/g),贫 Y(11.4～13.2μg/g)和 HREE(如 Yb=1.16～1.26μg/g),以及低(^(87)Sr/^(86)Sr)_i(0.7041～0.7043)和高ε_(Nd)(t)(0.3～2.3)。这些火山岩在元素-同位素组成上明显不同于浦江地区或区域上的晚中生代中酸性火山岩,而与现代俯冲带产出的埃达克岩类似。由于这些岩石相对于晚中生代的基性岩浆具有更低的(^(87)Sr/^(86)Sr)_i 比值,因此难以通过玄武岩浆的分离结晶或同化混染作用来解释,最有可能是地壳部分熔融的产物,在构造背景方面,目前还没有确切的证据说明区域存在晚中生代洋壳的俯冲作用,我们倾向于认为劳村组埃达克质火山岩可能为新增生玄武质地壳部分熔融的结果,其形成与区域上中生代地壳增生作用有直接的动力学联系。

关键词：埃达克质火山岩岩石成因浙江浦江晚中生代

海南岛屯昌玄武质科马提岩Sm-Nd同位素年龄及其地质意义

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地质科学 2000年第2期35卷 240-244页

作者：梁新权范蔚茗许德如中国科学院长沙大地构造研究所长沙410013

海南岛屯昌玄武质科马提岩成岩时代一直未获解决。作者利用 Sm- Nd同位素法测试了 5件样品 ,获得岩石 Sm- Nd同位素等时线年龄 1 687± 1 0 Ma,及与其相近的 Nd模式年龄 1 637- 1 756Ma。同时获得了钕同位素初始比值 INd=0 .51 0 796± ... 详细信息

海南岛屯昌玄武质科马提岩成岩时代一直未获解决。作者利用 Sm- Nd同位素法测试了 5件样品 ,获得岩石 Sm- Nd同位素等时线年龄 1 687± 1 0 Ma,及与其相近的 Nd模式年龄 1 637- 1 756Ma。同时获得了钕同位素初始比值 INd=0 .51 0 796± 0 .0 0 0 0 0 6( 2σ) ,εNd( T) =+ 6.64。表明玄武质科马提岩结晶年龄为古元古代 ( 1 687Ma) ,反映了海南岛在古元古时期的壳

关键词：钐-钕年龄玄武质科马提岩南海成岩时代

Observation of an upward lightning flash with 21 upward positive leaders initiated from different wind turbines in wind farm

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High Voltage 2024年第1期9卷 163-171页

作者： Li Cai Yifeng Ke Wenchao fan Ruisheng Yan Mi Zhou Jianguo Wang Yadong fan Engineering Research Center of Ministry of Education for Lightning Protection and Grounding Technology School of Electrical Engineering and AutomationWuhan UniversityWuhanChina

As the wind turbine height increases,the probability of multiple upward leaders flashes within the wind farm *** this study,an upward lightning flash containing 21 upward positive leaders(UPLs)initiated from different wind turbines in Zhangbei Wind Farm was *** average speed of the UPLs was 1.2×10^(5) m/s,which mostly decreased to zero before reaching the cloud *** four UPLs developed to cloud height,with prolonged periods of bright light on three of them and with a minimum duration of 126 ms.A total of nine return strokes occurred on the other two dissipated leader channels,and the numbers of strokes on the two channels was six and three,*** average interstroke interval for the return strokes was 10.5 *** of these nine return strokes had peak currents smaller than 10 *** high-speed video frames confirmed that competition does exist between the UPLs,and the range of shielding effects increases as the height of the ULs *** effect of fan rotation on the initiation of upward leaders and the shielding effect between the wind turbines and upward leaders are discussed.

关键词： flash return initiated

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盆地沉积物示踪源区山脉隆升剥露的几种方法

地质科技情报 1999年第2期18卷 85-89页

作者：王岳军范蔚茗林舸中国科学院长沙大地构造研究所

简要介绍了盆地沉积物示踪山脉隆升剥蚀的几种方法并给以实例分析。与造山带隆升过程相伴生的沉积盆地记录了造山带隆升的许多宝贵信息，但长期以来，利用盆地沉积物反演源区背景常局限于盆地沉积物碎屑组分、副（重）矿物组合及元素地... 详细信息

简要介绍了盆地沉积物示踪山脉隆升剥蚀的几种方法并给以实例分析。与造山带隆升过程相伴生的沉积盆地记录了造山带隆升的许多宝贵信息，但长期以来，利用盆地沉积物反演源区背景常局限于盆地沉积物碎屑组分、副（重）矿物组合及元素地球化学特征的变化，近年国外已开始利用盆地沉积物中颗粒锆石Ｕ－Ｐｂ年龄谱、Ｎｄ同位素组成、矿物（如黑云母、磷灰石等）热年代学方法示踪盆地沉积物物源性质及物源贡献比例。

关键词：盆地沉积物示踪源区山脉隆升铀-铅剥露

Segment-wise learning control for trajectory tracking of robot manipulators under iteration-dependent periods

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Science China(Information Sciences) 2024年第3期67卷 155-166页

作者： fan ZHANG Deyuan MENG Kaiquan CAI The Seventh Research Division Beihang University School of Automation Science and Electrical Engineering Beihang University School of Electronics and Information Engineering Beihang University

This paper is concerned with the amplitude boundedness problem of adaptive iterative learning control(AILC) for robot manipulators operating with iteration-dependent periods. By introducing virtual memory slots for storing historical data, a practical AILC method is proposed to achieve the segmentwise learning. This method requires less memory storage for historical information of previous iterations,especially in comparison with that of the conventional AILC methods using point-wise learning *** is shown that not only the energy boundedness but also the amplitude boundedness of estimates and inputs of practical AILC can be guaranteed. Moreover, the practical AILC method can achieve the perfect tracking objective regardless of iteration-dependent periods when the robot manipulators have a persistent full learning property. In addition, a solution to the visual manipulator platform is provided and deployed based on Coppeliasim and Matlab, which helps to show the amplitude boundedness of learning results and the perfect tracking performances of the proposed practical AILC method for robot manipulators.

关键词： amplitude boundedness iteration-dependent period iterative learning control robot manipulator segment-wise virtual memory slot

Process in laser drilling of deep microholes without taper on metal materials

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Science China(Technological Sciences) 2024年第1期67卷 37-59页

作者： fan RunZe MEI XueSong CUI JianLei State Key Laboratory for Manufacturing Systems Engineering Xi’an Jiaotong UniversityXi’an 710054China

Deep microhole machining is currently a prominent research area within the aerospace field,encompassing blade film cooling and fuel injection control ***,taper defects in metal materials may lead to performance degradation or even structural damage over a component’s *** and helical drilling,facilitated by ultrashort pulse lasers,have proven more suitable for achieving high-precision,deep holes in metal ***,excessive repetition rates can also result in severe thermal *** methods are commonly employed for controlling taper,including parameter optimization,assistance,and secondary *** laser beam drilling is widely utilized and has been integrated into relevant machining systems for commercial *** deep microholes include film cooling holes and injection *** drilling is a potential machining method for new materials in the aerospace *** laser drilling processing has been studied,numerous related scientific challenges and technical difficulties must be addressed before practical implementation.

关键词： aerospace laser drilling deep microhole taper control

Nearly degenerate ground states of a checkerboard antiferromagnet and their bosonic interpretation

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 84-89页

作者： Haiyuan Zou fan Yang Wei Ku Key Laboratory of Polar Materials and Devices(MOE) School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China Department of Physics Beijing Institute of TechnologyBeijing 100081China Tsung-Dao Lee Institute Shanghai 200240China Key Laboratory of Artificial Structures and Quantum Control(Ministry of Education) Shanghai 200240China Shanghai Branch Hefei National LaboratoryShanghai 201315China

The spin-1/2 model system with antiferromagnetic(AF) couplings on a J1-J2checkerboard lattice, known as the planar pyrochlore model, is strongly frustrated and associated with a two-to-one dimensional crossover. Using the Projected Entangled Simplex States tensor network ansatz, we identify a large number of nearly degenerate states in the frustrated region(J_(1)

关键词： tensor networks frustrated magnetism dimensional crossover degenerate states

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关于雷诺方程的渐近解

上海交通大学学报 1980年第1期 29-52页

作者：范伟民上海交通大学应用数学系

本文主要证明了如下问题:[ε（H（X）+εH1（X））YY′]′-[（G（X）+εG1（X））Y]′=M（X）+εM1（X）Y（0,ε）=Y（1,ε）=1在H（X）,G（X）,M（X）,H1（X）,G1（X）,M1（X）满足一定条件下,和参数ε>0且充分小时,存在解且唯一。并... 详细信息

本文主要证明了如下问题:[ε（H（X）+εH1（X））YY′]′-[（G（X）+εG1（X））Y]′=M（X）+εM1（X）Y（0,ε）=Y（1,ε）=1在H（X）,G（X）,M（X）,H1（X）,G1（X）,M1（X）满足一定条件下,和参数ε>0且充分小时,存在解且唯一。并确定了解的一致有效渐近展开式。更一般地（εH（X,ε）YY′）′-（G（X,ε）Y）′=M（X,ε）Y（0,ε）=Y（1,ε）=1在H（x,ε）,G（X,ε）,M（X,ε）满足一定条件时,且参数ε>0充分小,也有解的存在性及唯一性,及解的一致有效渐近展开式。

关键词：渐近解一致有效解的存在性唯一性雷诺方程运动方程积分方程渐近展开展开(数学)