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A Kungurian Oceanic Upwelling on Yangtze Platform: Evidenced by δ^(13) C_(org) and Authigenic Silica in the Lower Chihsia Formation of Enshi Section in South China

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Journal of Earth Science 2015年第2期26卷 211-218页

作者： hao Yu Hengye Wei Key Laboratory of Orogenic Belts and Crustal Evolution MOE Peking University College of Earth Sciences East China Institute of Technology

The Late Paleozoic Ice Age across Carboniferous and Permian had a significant impact on the Kungurian （Upper Cisuralian series of Permian） Chihsia Formation in South China. This re- suited in a unique interval with features such as the lack of reef in Chihsian limestone, widespread stinkstone and nodular/bedded chert. The Chihsia limestone （Kungurian stage） deposited during a time of cooling was resulted from oceanic upwelling. Here we present evidence for this upwelling using sev- eral geochemical analyses： bulk organic carbon isotope, biomarker molecular geochemical data, and authigenic silica of the stinkstone member in the lower Chihsia Formation of the Kuangurian stage from the Enshi Section in western Hubei Province, South China. The lower part of the stinkstone member shows a rapid organic carbon isotope excursion with a -3%o shift triggered by the upwelling of 13C-depleted bottom water. The concurrent rapid increasing of authigenic silica content resulted from the enhanced supply of dissolved silica in the upwelling water mass. This upwelling at the Enshi Section also led to relative high TOC content, accounting for the widespread stinkstone in the lower Chihsia Formation during the Kungurian stage in Permian.

关键词： Chihsia Formation Enshi Section organic carbon isotope authigenic silica upwelling.

MD simulations of loading rate dependence of detwinning deformation in nanocrystalline Ni

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Science China(Physics,Mechanics & Astronomy) 2013年第3期Mechanics & Astronomy) .卷 491-497页

作者： SU hao TANg QiHeng State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of Sciences

Molecular dynamics simulations are performed to investigate the deformation behavior of nanocrystalline Ni with pre-twin atom *** simulation sample is composed of four grains with average size 12 *** simulation technique of isobaric-isothermal ensemble(NPT) with high pressure is applied to obtain a sample with two circle *** uniaxial tensile and shear loading,as well as different detwinning deformation behaviors are *** uniaxial tension the detwinning deformation is induced by the event of grain growth,and it is supported by local energy *** the shear loading the detwinning deformation is related to the loading *** results show that there may be a critical shear *** the shear rate is sufficiently high the circle twin is found to be failed;as the shear rate is less than that rate,the size of circle twin become smaller and gradually approach a constant *** simulation results are in good agreement with experiment observation.

关键词： molecular dynamics simulation detwinning loading rate

A Nontrivial Homotopy Element of Order p2 Detected by the Classical Adams Spectral Sequence

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Chinese Annals of Mathematics,Series B 2018年第1期39卷 1-8页

作者： hao zhao Linan zHONg School of Mathematical Sciences South China Normal UniversityGuangzhou 510631China Department of Mathematics Yanbian UniversityYanji 133002JilinChina

Let p be an odd *** authors detect a nontrivial element p of order p^2 in the stable homotopy groups of spheres by the classical Adams spectral *** is represented by a_0^(p-2)h_1 ∈ Ext_A^(p-1,pq+p-2)(z/p,z/p) in th... 详细信息

关键词： Stable homotopy groups of sphere Adams spectral sequence May spectral sequence Massey product

Bioinspired Underwater Navigation Using Polarization Patterns Within Snell’s Window

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China Ocean Engineering 2023年第4期37卷 628-636页

作者： CHENg hao-yuan YU Shi-min YU hao zHU Jin-chi CHU Jin-kui Department of Mechanical and Electrical Engineering Ocean University of ChinaQingdao 266100China Key Laboratory of Ocean Engineering of Shandong Province Ocean University of ChinaQingdao 266100China Key Laboratory for Micro/Nano Technology and System of Liaoning Province Dalian University of TechnologyDalian 116024China

Aiming at the requirement of autonomous navigation capability of the underwater unmanned vehicle(UUV),a novel bionic method for underwater navigation based on polarization pattern within Snell’s window is *** by creatures,polarization navigation is a satellite-free navigation scheme and has great potential to be used in the ***,because of the complex underwater environment,whether UUV polarization navigation can be realized is *** illustrate the feasibility of underwater polarization navigation,we firstly establish the model of under-water polarization patterns to prove the stability and predictability of the underwater polarization pattern within Snell’s ***,we carry out static and dynamic experiments of underwater heading determination based on developed polarization information detection ***,we obtain underwater polarization patterns and conduct the tracking experiment at different water *** experimental results of the underwater polarization patterns are consistent with the simulation,which proves the correctness of the proposed *** the water depth of 5 m,the average angle and position error of the tracking experiment are 14.3508°and 4.0812 m,*** is illustrated that underwater polarization navigation is realizable and the precision can meet the real-time navigation requirements of *** study promotes the improvement of underwater navigation ability and the development of marine equipment.

关键词： underwater navigation polarization pattern heading determination tracking experiment

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基于串行及并行恢复的电力系统重构

电力系统自动化 2015年第14期39卷 60-67页

作者：赵腾张焰张志强上海交通大学电子信息与电气工程学院上海市200240 中国电力科学研究院北京市100192

研究大停电后的电力系统重构问题对于系统的快速安全恢复有着重要意义。文中在对大停电后电力系统串行及并行恢复概念进行新的阐述的基础上,提出一种基于串行和并行恢复的系统重构优化算法。该算法采用分步探索寻优方式,动态地考虑系统... 详细信息

研究大停电后的电力系统重构问题对于系统的快速安全恢复有着重要意义。文中在对大停电后电力系统串行及并行恢复概念进行新的阐述的基础上,提出一种基于串行和并行恢复的系统重构优化算法。该算法采用分步探索寻优方式,动态地考虑系统恢复过程中的功率平衡以及目标节点在网络中的重要程度等问题,在保证重构方案灵活性的基础上对串行恢复过程中重构网架的拓扑结构进行整体优化,引入分区距离灵敏度指标为并行恢复过程中各子系统间的有效配合提供定量参考,并对每一步得到的目标系统进行潮流校验以保证重构方案的可行性。以IEEE 118节点系统和华东电网为例验证了算法的有效性。

关键词：大停电串行恢复并行恢复系统重构路径寻优

Limiting Behaviors for Longest Consecutive Switches in anⅡD Bernoulli Sequence

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Acta Mathematica Sinica,English Series 2023年第6期39卷 1138-1146页

作者： Chen Xu hao Ting MA College of Mathematics Sichuan UniversityChengdu 610065P.R.China

In this paper we mainly discuss lower and upper bounds for the length of longest consecutive switches inⅡD Bernoulli *** work is an extension of results for longest consecutive switches in unbiased coin-tossing,and m... 详细信息

关键词： Longest consecutive switches lower and upper bounds Borel-Cantelli lemma

A time and charge measurement board for muon tomography of high-z materials

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Nuclear Science and Techniques 2017年第3期28卷 104-108页

作者： Shi-Tao Xiang hao Liang State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026 China Department of Modern Physics University of Science and Technology of China Hefei 230026 China

In this paper, a versatile time and charge measurement(MQT) board for muon tomography is described in detail. For time measurement, the general-purpose timeto-digital converter(TDC) chip TDC-gP2 is employed,while for charge measurement, digitization plus numerical integration in field programmable gate array is *** tests demonstrate that the total 32 channels of two MQT boards have a time resolution of superior than100 ps, with excellent linearity for time and charge measurement.

关键词： Time and charge measurement generalpurpose time-to-digital converter (TDC-gP2) Muon tomography

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喷印金属微滴撞击粗糙表面的分子动力学模拟

原子与分子物理学报 2025年第4期42卷 73-80页

作者：苏仁健陈小勇游自浩桂林电子科技大学机电工程学院桂林541004 广西制造系统与先进制造技术重点实验室桂林541004

研究金属微滴撞击固体表面的行为对预测微滴形态和实现高精度的喷印制造具有重要的意义.然而,由于微纳尺度下金属微滴撞击实验的难以开展,目前涉及金属微滴撞击粗糙表面的形态变化和热毛细效应机理尚不清楚.本文采用分子动力学模拟研究... 详细信息

研究金属微滴撞击固体表面的行为对预测微滴形态和实现高精度的喷印制造具有重要的意义.然而,由于微纳尺度下金属微滴撞击实验的难以开展,目前涉及金属微滴撞击粗糙表面的形态变化和热毛细效应机理尚不清楚.本文采用分子动力学模拟研究了镓铟微滴撞击粗糙表面的动态行为,定量分析了撞击速度、粗糙结构和不同温度对微滴撞击行为的影响.结果表明:随着撞击速度的提高,微滴先后呈现沉积、弹跳和破碎飞溅三种模式,且微滴的最大铺展因子与韦伯数呈幂函数关系.此外,通过修饰基底粗糙结构发现,结构间距或高度的变化对微滴的弹跳行为存在不同的影响机制,可以有效促使或抑制微滴的弹跳行为.最后,分析得出随着温度的提高,微滴的铺展直径会变大,产生的黏性耗散也会增大.研究结果对金属微滴撞击行为的有效预测提供了理论基础.

关键词：金属微滴撞击粗糙基底分子动力学

Efficiency analysis and optimization of wireless power transfer system for freely moving biomedical implants

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Science China(Technological Sciences) 2017年第1期60卷 91-101页

作者： Shao Qi LIU hao FANg XueLin State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China

In the wireless power transfer system for freely moving biomedical implants,the receiving unit was generally inefficient for the reason that its design parameters including the receiving coil's dimension and receiving circuits' topology were always determined by *** order to build the relationship between these parameters and the total transfer efficiency,this paper developed a novel efficiency model based on the impedance model of the coil and the circuit model of the receiving *** to the design constraints,the optimal design parameters in the worst case were *** results indicate that the combination of the two-layered receiving coil and half-bridge rectifier has more advantages in size,efficiency and safety,which is preferred in the receiving ***,when the load resistance increases,the optimal turn number of the receiving coil basically keeps constant and the corresponding transmitting current and total efficiency *** 100 Ω load,the transmitting current and total efficiency in the worst case were measured to be 5.30 A and 1.45% respectively,which are much better than the published *** general,our work provides an efficient method to determine the design parameters of the wireless power transfer system for freely moving biomedical implants.

关键词： wireless power transfer system capsule endoscope freely moving biomedical implants receiving coil coil optimization efficiency