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Geochronology,Geochemistry,and Sr-Nd-Hf Isotopes of the Diorite Porphyrites from the Weining Beishan Area,Ningxia Hui Autonomous Region:Constraints on Their Source and Tectonic Implications

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Journal of Earth Science 2024年第2期35卷 462-475页

作者： Anlu Liu Lianfu Hai Jinke Liu Xiaojun Zhang haifeng Li Fengshun Zhao Guoliang Zhao Jinhe Bai Yifu Museum China University of GeosciencesWuhan430074China School of Earth Resources China University of GeosciencesWuhan430074China Mineral Geological Survey Institute of Ningxia Hui Autonomous Region Yinchuan750021China National Demonstration Center for Experimental Mineral Exploration Education China University of GeosciencesWuhan430074China Coal Geological Survey Institute of Ningxia Hui Autonomous Region Yinchuan750021China Zhuhai Engineering Investigation Institute of Guangdong Province Zhuhai519000China

The Weining Beishan area of Ningxia Hui Autonomous Region is located at on the western edge of the Helanshan tectonic belt,which is a tectonic joint among Alxa Block,Ordos Block,and North Qilian orogenic ***,the tectonic evolution of this area remains unclear due to the lack of magmatic *** paper conducted researches on geochronology,geochemistry,and Sr-Nd-Hf isotopes of the diorite porphyrites exposed in the Weining Beishan *** zircon U-Pb dating yields two ages of 145.0±1.1 and 146.2±1.5 Ma,and the whole-rock geochemical data indicate that the diorite porphyrites are metaluminous to weakly peraluminous and high-K calc-alkaline *** characteristics of highly initial^(87)Sr/^(86)Sr ratios(0.70816 to 0.71047),negativeε_(Nd)(t)(−8.9 to−8.4),and negativeε_(Hf)(t)(−13.8 to−21.2)indicate that the diorite porphyrites originated from partial melting of the middle-lower ancient crust related to the North China *** with the regional geology,we suggested that partial melting was triggered by a tectonic activity of deep faults cutting through the crust under the regional stress transformation from compressing to extension during the Late Jurassic–Early Cretaceous,which is probably related to the westward subduction of the Paleo-Pacific Plate.

关键词： zircon U-Pb dating Sr-Nd-Hf isotopes magma source diorite porphyrite Weining Beishan area Ningxia Hui Autonomous Region geochronology geochemistry

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小波算法在变压器励磁涌流中的应用研究

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电力系统保护与控制 2017年第8期45卷 121-125页

作者：孙庆森张海峰王猛王华兴国网泰安供电公司山东泰安271000

为了满足电气化设备对高性能变压器的需求,针对大功率变压器中存在的励磁涌流现象展开研究,并建立了仿真模型。利用一种新型的小波算法对变压器中的励磁涌流现象进行分析和数学建模,并研究了三相变压器的励磁涌流产生机制和信号提取方法... 详细信息

为了满足电气化设备对高性能变压器的需求,针对大功率变压器中存在的励磁涌流现象展开研究,并建立了仿真模型。利用一种新型的小波算法对变压器中的励磁涌流现象进行分析和数学建模,并研究了三相变压器的励磁涌流产生机制和信号提取方法,建立了精确的故障识别模型。最后,利用Matlab/Simulink软件设计了仿真系统,实现了对三相变压器的励磁涌流波形识别。仿真结果表明,该仿真模型能够有效提取出变压器励磁涌流的有关特性,为提高变压器的性能提供了理论支持。

关键词：变压器励磁涌流小波算法建模信号提取

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Subsurface deformation mechanism and the interplay relationship between strength–ductility and fretting wear resistance during fretting of a high-strength titanium alloy

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Friction 2024年第10期12卷 2259-2280页

作者： Yanlin TONG Ke HUA Haoyang XIE Yue CAO Zhuobin HUANG Zhenpeng LIANG Xiaolin LI Hongxing WU haifeng WANG State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an 710072China

Fretting wear damage of high-strength titanium fasteners has caused a large number of disastrous ***,it is believed that both high strength and excellent ductility can reduce fretting wear ***,whether strength and ductility are contradictory or not and their appropriate matching strategy under the external applied normal stress(Fw)are still confusing ***,by analyzing the subsurface-microstructure deformation mechanism of several samples containing variousαprecipitate features,for the first time,we design strategies to improve fretting damage resistance under different matching relation between Fw and the tensile strength of materials(Rm).It is found that when Fw is greater than Rm or Fw is nearly equivalent to Rm,the deformation mechanism mainly manifests as serious grain fragmentation ofβandαGB *** deformation in large areas only reduces damage to a limited *** is crucial to improve the strength to resist cracking and wear,but it is of little significance to improve the ***,when Fw is far less than Rm,coordinated deformation ability reflected by ductility plays a more important *** deformation mechanism mainly manifests as localized deformation ofβandαGB constituents(kinking induced by twinning and spheroidizing).A unique composite structure of nano-grained/lamellar layer and localized deformation transition layer reduces fretting damage by five times compared with a single nanograined *** when the strength is great enough,improving the plasticity can reduce *** study can provide a principle for designing fretting damage resistant alloys.

关键词： fretting wear high-strength titanium alloy microstructures subsurface deformation

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Design of Signal Lamp Filament Monitoring Alarm Instrument

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Journal of Electronic Research and Application 2024年第5期8卷 38-45页

作者： haifeng Zhu Suzhou Technician College Jiangsu Province Suzhou 215000China

To improve the reliability of the light emitting diode(LED)signal lamp filament current monitoring alarm instrument for metro systems,a new type of hot standby online monitoring apparatus was developed which is based on synchronous transmission data(STD)bus *** this system,a double hot standby mode can be achieved by adopting bus *** addition,to detect the effective value of alternating current which is from 0 to 200 mA in the signal lamp lighting circuit,a precision rectifier signal conditioning circuit and an isolated acquisition circuit were *** new type of alarm instrument has high detection accuracy and could meet the functional requirements for metro signal systems after comparing it with some industry products that were applied on the spot.

关键词： Signal lamp Monitoring alarm instrument Precision rectifier signal conditioning circuit

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Theoretical and Experimental Performance Analysis on Error-Bounded Quantum Search Process

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Journal of Systems Science & Complexity 2024年

作者： FU Jianling XU Ming QIAN haifeng LI Zhibin Shanghai Institute for AI Education East China Normal University Shanghai Key Laboratory of Trustworthy Computing East China Normal University

Grover's algorithm(a. k. a. quantum search process) is one of the most distinguished quantum algorithms, addressing the fundamental problem — How to find goal records from a huge but unstructured database efficiently. It can achieve a relatively optimal success probability after a few Grover iterations for amplitude amplification, which results in a quadratic speed-up in the whole process in terms of the size of database. However, it does not guarantee to achieve that probability within a user-specified error tolerance. So error-bounded quantum search process comes into being. The existing methods introduce extra qubits to meet that tolerance, or exploit high-precision(nonbasic) gates,each of which would be converted to a sequence of basic gates and thus costs much more computational units. In this paper, the authors employ the strategy of performing more Grover iterations expecting one of a series of local optima to meet the tolerance. To ensure that it works rigorously, the authors identify and exclude three exceptional instances by algebraic number theory, which is reported for the first time. Then the authors analyze the theoretical complexity of the employed method. It turns out to be in time exponential in the encoding size of the tolerance using basic gates, comparable to the existing method's, while extra space consumption is saved. The experimental performance is validated by extensive examples from real-world data sets ASRS and public Amazon review.

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Three-dimensional magnetization reconstruction from electron optical phase images with physical constraints

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 122-132页

作者： Boyao Lyu Shihua Zhao Yibo Zhang Weiwei Wang Fengshan Zheng Rafal E.Dunin-Borkowski Jiadong Zang haifeng Du Anhui Province Key Laboratory of Low-Energy Quantum Materials and Devices High Magnetic Field LaboratoryHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Science Island Branch Graduate School of University of Science and Technology of ChinaHefei 230026China Department of Physics and Astronomy University of New HampshireDurham 03824USA Department of Physics The City College of New YorkNew York 10031USA Physics Program Graduate Center of the City University of New YorkNew York 10016USA Department of Chemistry University of New HampshireDurham 03824USA Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601China Spin-X Institute Center for Electron MicroscopySchool of Physics and OptoelectronicsState Key Laboratory of Luminescent Materials and DevicesGuangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional MaterialsSouth China University of TechnologyGuangzhou 511442China Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons Forschungszentrum JülichJülich 52425Germany

The ability to characterize three-dimensional(3D)magnetization distributions in nanoscale magnetic materials and devices is essential to fully understand their static and dynamic magnetic *** contrast techniques in the transmission electron microscope(TEM),such as electron holography and electron ptychography,can be used to record two-dimensional(2D)projections of the in-plane magnetic induction of 3D nanoscale *** the 3D magnetic induction can in principle be reconstructed from one or more tilt series of such 2D projections,conventional tomographic reconstruction algorithms do not recover the 3D magnetization within a sample ***,we use simulations to describe the basis of an improved model-based algorithm for the tomographic reconstruction of a 3D magnetization distribution from one or more tilt series of electron optical phase images recorded in the *** algorithm allows a wide range of physical constraints,including a priori information about the sample geometry and magnetic parameters,to be *** also makes use of minimization of the micromagnetic energy in the loss *** demonstrate the reconstruction of the 3D magnetization of a localized magnetic soliton—a hopfion ring—and discuss the influence of noise,choice of magnetic constants,maximum tilt angle and number of tilt axes on the *** algorithm can in principle be adapted for other magnetic contrast imaging techniques in the TEM,as well as for other magnetic characterization techniques,such as those based on X-rays or neutrons.

关键词： three-dimensional magnetization vector field tomography differentiable programming electron holography micromagnetism

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北京地铁施工缝防水处理方法

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隧道建设 2008年第1期28卷 85-88页

作者：孟海峰中铁隧道集团二处有限公司北京铁路地下直径线项目部北京100045

针对现正施工使用的地铁结构施工缝防水进行详细描述及比较,并从施工层面及结果层面分析了各种施工缝防水处理方法的利弊。具体介绍了施工缝的三种处理方法:双道遇水膨胀嵌缝胶与注浆管配合防水、钢边橡胶止水带、缓膨胀型膨润土橡胶遇... 详细信息

针对现正施工使用的地铁结构施工缝防水进行详细描述及比较,并从施工层面及结果层面分析了各种施工缝防水处理方法的利弊。具体介绍了施工缝的三种处理方法:双道遇水膨胀嵌缝胶与注浆管配合防水、钢边橡胶止水带、缓膨胀型膨润土橡胶遇水膨胀止水条,及三种处理方法的材料材质的性能、安装方法和防水原理,以及三种方法的适用范围。

关键词：地铁施工缝防水施工

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苹果种植技术与病虫害防治措施

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现代农业研究 2020年第7期26卷 139-140页

作者：孟海凤泰安市林业局山东泰安271000

苹果树在传统的种植方式下容易出现各类病虫害,种植户在应对病虫害时,更多的是选择喷洒农药,这样会在一定程度上威胁人体健康。为防止应用化学农药治理苹果病虫害,促进苹果健康生长,应改进防治技术。本文主要围绕苹果种植技术以及防治... 详细信息

苹果树在传统的种植方式下容易出现各类病虫害,种植户在应对病虫害时,更多的是选择喷洒农药,这样会在一定程度上威胁人体健康。为防止应用化学农药治理苹果病虫害,促进苹果健康生长,应改进防治技术。本文主要围绕苹果种植技术以及防治病虫害技术展开分析,提出防治苹果病虫害的主要技术,以供参考。

关键词：苹果树种植技术病虫害防治

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An Empirical Study on Google Research Football Multi-agent Scenarios

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Machine Intelligence Research 2024年第3期21卷 549-570页

作者： Yan Song He Jiang Zheng Tian haifeng Zhang Yingping Zhang Jiangcheng Zhu Zonghong Dai Weinan Zhang Jun Wang Institute of Automation Chinese Academy of SciencesBeijing100190China Digital Brain Lab Shanghai200001China ShanghaiTech University Shanghai200001China Huawei Cloud Guiyang550003China Shanghai Jiao Tong University Shanghai200001China University College London LondonWC1E 6PTUK

Few multi-agent reinforcement learning (MARL) researches on Google research football (GRF) focus on the 11-vs-11 multi-agent full-game scenario and to the best of our knowledge, no open benchmark on this scenario has been released to the public. In this work, we fill the gap by providing a population-based MARL training pipeline and hyperparameter settings on multi-agent football scenario that outperforms the bot with difficulty 1.0 from scratch within 2 million steps. Our experiments serve as a reference for the expected performance of independent proximal policy optimization (IPPO), a state-of-the-art multi-agent reinforcement learning algorithm where each agent tries to maximize its own policy independently across various training configurations. Meanwhile, we release our training framework Light-MALib which extends the MALib codebase by distributed and asynchronous implementation with additional analytical tools for football games. Finally, we provide guidance for building strong football AI with population-based training and release diverse pretrained policies for benchmarking. The goal is to provide the community with a head start for whoever experiment their works on GRF and a simple-to-use population-based training framework for further improving their agents through self-play. The implementation is available at https://***/Shanghai-Digital-Brain-Laboratory/DB-Football.

关键词： Multi-agent reinforcement learning(RL) distributed RL system population-based training reward shaping game theory

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MOF-templated tubular Ni_(1−x)Co_(x)S_(2)-CdS heterojunction with intensified direct Z-scheme charge transmission for highly promoted visible-light photocatalysis

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Nano Research 2024年第7期17卷 6281-6293页

作者： Chuan Jiang Yuanxin Qiu Xinxin Xin Yanyan Li Huilin Li Hui Wang Jixiang Xu haifeng Lin Lei Wang Volodymyr Turkevych Key Laboratory of Eco-chemical Engineering International S&T Cooperation Foundation of Eco-chemical Engineering and Green ManufactureCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization Key Laboratory of Rubber-Plastics of Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdao 266042China V.Bakul Institute for Superhard Materials National Academy of Sciences of UkraineKyiv 04074Ukraine

Hollow semiconductor nanostructures with direct Z-scheme heterojunction have significant advantages for photocatalytic reactions,and optimizing the interfacial charge transmission of Z-scheme heterojunction is the hinge to achieve excellent solar conversion *** this work,tubular Ni_(1−x)Co_(x)S_(2)-CdS heterostructures with reinforced Z-scheme charge transmission were constructed through an In-metal-organic framework(MOF)templated *** Z-scheme charge transfer mechanism was sufficiently confirmed by combining density functional theory(DFT)calculation,X-ray photoelectron spectroscopy(XPS),surface photovoltage spectroscopy(SPV),and radical testing ***,the use of sodium citrate complexant contributes to the formation of intimate heterointerface,and the Fermi level gap between CdS and NiS_(2)is enlarged through Co doping into NiS_(2),which enhances the built-in electric field and photo-carriers transmission driving force for Ni_(1−x)Co_(x)S_(2)-CdS heterojunction,resulting in an evidently promoted activity toward H2 evolution reaction(HER).Under visible-light(λ>400 nm)irradiation,the Ni_(1−x)Co_(x)S_(2)-CdS composite with 10 mol%Co doping and 80 wt.%CdS(NC_(0.10)S-80%CdS)achieved an outstanding HER rate up to 35.94 mmol·g^(−1)·h^(−1)(corresponding to the apparent quantum efficiency of 34.7%at 420 nm),approximately 76.4 times that of 3 wt.%Pt-loaded CdS and it is much superior to that of most CdS-based photocatalysts ever ***,the good photocatalytic durability of Ni_(1−x)Co_(x)S_(2)-CdS heterostructures was validated by cycling and long-term HER *** work could inspire the development of high-performance Z-scheme heterojunction via optimizing the morphology and interfacial charge transmission.

关键词： tubular heterostructure Z-scheme charge transmission interfacial coupling built-in electric field visible-light photocatalysis

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