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Preparation of Laser Cladding Coating Undercooling Cu-based Alloy and Co on Non-equilibrium Solidification Structure

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 463-472页

作者：田徐铭 cao shichao HOU Kai HOU Xiaopeng WANG Hongfu 张煜 Department of Outpatient Xinzhou People’s HospitalXinzhou 034099China School of Mechanical Engineering North University of ChinaTaiyuan 030051China Department of Neurosurgery Xinzhou People’s HospitalXinzhou 034099China Department of Orthopedics Xinzhou People’s HospitalXinzhou 034099China

The effect of the gradient content of Co element on the solidification process of Cu-based alloy under deep under cooling conditions was *** non-equilibrium solidification structure of the under cooled alloy samples were *** is found that the rapidly solidified alloy has undergone twice grain refinement during the undercooling *** and significance of the maximum undercooling refinement structure of Cu60Ni35Co5 at T=253 K were ***-density defects were observed,such as dislocations,stacking faults networks,and twinning *** standard FCC diffraction pattern represents that it is still a single-phase *** on the metallographic diagram,EBSD and TEM data analysis,it is illustrated that the occurrence of grain refinement under high undercooling is due to stress induced *** addition,the laser cladding technology is used to coat Co-based alloy(Stellite12) coating on 304 stainless steel substrate;the microstructure of the coating cross-section was *** was found that the microstructure of the cross-section is presented as columnar crystals,planar crystals,and disordered growth direction,so that the coating has better hardness and wear *** electrochemical corrosion of the substrate and coating,it can be seen that the Co and Cr elements present in the coating are more likely to form a dense passivation film,which improved the corrosion resistance of the coating.

关键词： non-equilibrium solidification structure undercooling recrystallization laser cladding coating

Characterization and spatial analysis of coseismic landslides triggered by the Luding Ms 6.8 earthquake in the Xianshuihe fault zone, Southwest China

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Journal of Mountain Science 2024年第1期21卷 160-181页

作者： GUO Changbao LI Caihong YANG Zhihua NI Jiawei ZHONG Ning WANG Meng YAN Yiqiu SONG Deguang ZHANG Yanan ZHANG Xianbing WU Ruian cao shichao SHAO Weiwei Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesBeijing 100081China Research Center of Neotectonism and Crustal Stability China Geological SurveyBeijing 100081China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Sichuan Institute of Geological Survey Chengdu 610081China

On September 5, 2022, a magnitude Ms 6.8 earthquake occurred along the Moxi fault in the southern part of the Xianshuihe fault zone located in the southeastern margin of the Tibetan Plateau,resulting in severe damage and substantial economic loss. In this study, we established a coseismic landslide database triggered by Luding Ms 6.8 earthquake, which includes 4794 landslides with a total area of 46.79 km^(2). The coseismic landslides primarily consisted of medium and small-sized landslides, characterized by shallow surface sliding. Some exhibited characteristics of high-position initiation resulted in the obstruction or partial obstruction of rivers, leading to the formation of dammed lakes. Our research found that the coseismic landslides were predominantly observed on slopes ranging from 30° to 50°, occurring at between 1000 m and 2500 m, with slope aspects varying from 90° to 180°. Landslides were also highly developed in granitic bodies that had experienced structural fracturing and strong-tomoderate weathering. Coseismic landslides concentrated within a 6 km range on both sides of the Xianshuihe and Daduhe fault zones. The area and number of coseismic landslides exhibited a negative correlation with the distance to fault lines, road networks, and river systems, as they were influenced by fault activity, road excavation, and river erosion. The coseismic landslides were mainly distributed in the southeastern region of the epicenter, exhibiting relatively concentrated patterns within the IX-degree zones such as Moxi Town, Wandong River basin, Detuo Town to Wanggangping Township. Our research findings provide important data on the coseismic landslides triggered by the Luding Ms 6.8 earthquake and reveal the spatial distribution patterns of these landslides. These findings can serve as important references for risk mitigation, reconstruction planning, and regional earthquake disaster research in the earthquake-affected area.

关键词： Luding earthquake Coseismic landslides Remote sensing interpretation Spatial distribution Xianshuihe fault Earthquake fault

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不同工况下电机车停车控制方法的研究

自动化应用 2024年第5期65卷 79-80,83页

作者：曹世超永定庄煤业有限公司山西大同037000

为提升电机车停车的稳定性和精准性,实现精准制动,采用了基于模糊PID的电流环、转矩环的双闭环矢量控制永磁同步电机。在不同初始停车速度下,10次停车距离误差最大为-0.16 m;在不同停车距离下,11次停车距离误差最大为-0.19 m;在不同坡度... 详细信息

为提升电机车停车的稳定性和精准性,实现精准制动,采用了基于模糊PID的电流环、转矩环的双闭环矢量控制永磁同步电机。在不同初始停车速度下,10次停车距离误差最大为-0.16 m;在不同停车距离下,11次停车距离误差最大为-0.19 m;在不同坡度下,7次停车距离误差最大为0.21 m。上述误差均小于±0.3 m,说明该停车控制方法能够有效实现电机车的精准停车。

关键词：电机车永磁同步电机模糊PID控制

Characteristics,origins,and significance of pyrites in deep-water shales

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Science China Earth Sciences 2024年第2期67卷 313-342页

作者： Chao LIANG shichao JI Yingchang cao Keyu LIU Jing WU Fang HAO National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580China School of Geosciences China University of PetroleumQingdao266000China Laboratory for Marine Mineral Resource Qingdao National Laboratory for Marine Science and TechnologyQingdao266071China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao266590China

As important metal sulfides in the geochemical cycle of sulfur,the characteristics and formation processes of pyrites can provide useful clues regarding their *** on previous findings,shale pyrites were divided into three major classes(euhedral pyrites,framboidal pyrites(framboids)and metasomatic pyrites)and six sub-classes in this *** the microscopic scale,each type of pyrite is associated with a different formation *** are formed by burst nucleation in environments with a homogeneous distribution of nutrients while euhedral pyrites are usually formed on pre-existing sites(such as=FeS on the minerals surface)in the heterogeneous *** pyrites formed by the replacement of other ions in accountable material by iron ions and hydrogen sulfide ions in hydrothermal *** morphology and isotope value of pyrite provide information to track the origins of their nutrient and characteristics of sulfur and iron *** addition,the trace element content of pyrite can serve as a proxy for paleo-ocean trace element abundance,indicating changes in atmospheric oxygen ***,pyrite can also serves as an indicator of shale gas reservoirs.

关键词： Shale Pyrite Sulfate reduction reaction Isotope fractionation Pyrite element

Flashover Characteristics of Dry Band-water band on Hydrophobic Surfaces

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 392-400页

作者： Xiaohan Wu Fanghui Yin Bin cao Daiming Yang shichao Shao Liming Wang Tsinghua-Berkeley Shenzhen Institute(TBSI) Shenzhen 518055China Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China Shenzhen Polytechnic School Shenzhen 518055China

Due to their outstanding anti-flashover characteristics,composite insulators have been extensively applied in power systems.A lot of research has investigated flashover characteristics of hydrophobic specimens with artificial water ***,the phenomenon is not consistent with that of the contaminated composite *** the test specimens covered with water droplets,there is no obvious leakage current before the flashover and no obvious relationship between flashover voltage and the conductivity of water *** the contaminated composite insulator surface,there are short continuous arcs on the insulators before critical flashover,making insulators look like a luminous *** that under these two conditions,the proportion of water along the insulation distance is different,the flashover characteristic of“dry band-water band”on a hydrophobicity surface is analyzed in the present *** influence of the water band parameter(including length,width,and conductivity)as well as the length of dry band is *** this basis,the arc generation and development process of the surface covered with“dry band-water band”is *** research results improve the understanding of the flashover process on contaminated composite insulators.

关键词： Flashover characteristics hydrophobicity partial arc water band

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刮板链间距对中部槽冲击特性的影响规律研究

机械管理开发 2023年第11期38卷 35-36,39页

作者：曹世超晋能控股煤业集团永定庄煤业公司山西大同037000

以某煤炭企业运行的刮板输送机为研究对象,借助EDEM仿真计算软件,开展了不同刮板链间距对中部槽冲击特性的影响规律研究。结果表明,随着落煤时间的增加,不同刮板链间距对应的冲击磨损深度和法向累计接触能量均呈现上升趋势,刮板链结构... 详细信息

以某煤炭企业运行的刮板输送机为研究对象,借助EDEM仿真计算软件,开展了不同刮板链间距对中部槽冲击特性的影响规律研究。结果表明,随着落煤时间的增加,不同刮板链间距对应的冲击磨损深度和法向累计接触能量均呈现上升趋势,刮板链结构形式对二者的影响程度为边双链>准边双链>中双链。刮板链结构形式影响落煤与中部槽接触面积是出现冲击磨损深度不同的主要原因,边双链结构接触面积最大,冲击磨损深度最大;刮板链结构形式影响刮板链布置位置是出现法向累计接触能量不同的主要原因,中双链结构两条刮板链靠中布置,缓冲作用最明显,法向累计接触能量最小。

关键词：刮板输送机刮板链间距中部槽冲击特性规律

Quantitative phase imaging based on holography:trends and new perspectives

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Light(Science & Applications) 2024年第7期13卷 1235-1277页

作者： Zhengzhong Huang Liangcai cao Department of Precision Instrument Tsinghua UniversityBeijing 100084China

In 1948,Dennis Gabor proposed the concept of holography,providing a pioneering solution to a quantitative description of the optical *** 75 years of development,holographic imaging has become a powerful tool for optical wavefront measurement and quantitative phase *** emergence of this technology has given fresh energy to physics,biology,and materials *** holography(DH)possesses the quantitative advantages of wide-field,non-contact,precise,and dynamic measurement capability for *** has unique capabilities for the propagation of optical fields by measuring light scattering with phase *** offers quantitative visualization of the refractive index and thickness distribution of weak absorption samples,which plays a vital role in the pathophysiology of various diseases and the characterization of various *** provides a possibility to bridge the gap between the imaging and scattering *** propagation of wavefront is described by the complex *** complex-value in the complex-domain is reconstructed from the intensityvalue measurement by camera in the ***,we regard the process of holographic recording and reconstruction as a transformation between complex-domain and real-domain,and discuss the mathematics and physical principles of *** review the DH in underlying principles,technical approaches,and the breadth of *** conclude with emerging challenges and opportunities based on combining holographic imaging with other methodologies that expand the scope and utility of holographic imaging even *** multidisciplinary nature brings technology and application experts together in label-free cell biology,analytical chemistry,clinical sciences,wavefront sensing,and semiconductor production.

关键词： holographic phase precise

Dynamic Setting Method of Assessment Indicators for Power Curves of Renewable Energy Sources Considering Scarcity of Reserve Resources

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 101-114页

作者： Minghao cao Jilai Yu the Department of Electrical Engineering Harbin Institute of TechnologyHarbinChina

With the increasing proportion of renewable energy sources(RESs)in power grid,the reserve resource(RR)scarcity for correcting power deviation of RESs has become a potential ***,the power curve of RES needs to be more rigorously *** RR scarcity varies during different time periods,so the values of assessment indicators should be dynamically *** assessment indicators in this paper include two aspects,i.e.,deviation exemption ratio and penalty ***,this paper proposes a method for dynamically calculating the supply capacity and RR cost,primarily taking into account the operating status of thermal units,forecast information of RES,and load ***,after clarifying the logical relationship between the degree of RR scarcity and the values of assessment indicators,this paper establishes a mapping function between *** on this mapping function,a dynamic setting method for assessment indicators is *** the future,RES will generally be equipped with battery energy storage systems(BESSs).Reasonably utilizing BESSs to reduce the power deviation of RESs can increase the expected income of ***,this paper proposes a power curve optimization strategy for RESs considering self-owned *** case study demonstrates that the dynamic setting method of assessment indicators can increase the revenue of RESs while ensuring that the penalty fees paid by RESs to the grid are sufficient to cover the RR ***,the power curve optimization strategy can help RESs further increase income and fully utilize BESSs to reduce power deviation.

关键词： Renewable energy battery energy storage system(BESS) power curve assessment reserve service parameter setting

Zeros of Complete Symmetric Polynomials over Finite Fields

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Journal of Systems Science & Complexity 2024年第4期37卷 1772-1788页

作者： cao Wei School of Mathematics and Statistics Minnan Normal UniversityZhangzhou 363000China

Wan and Zhang(2021) obtained a nontrivial lower bound for the number of zeros of complete symmetric polynomials over finite fields,and proposed a problem whether their bound can be *** this paper,the author improves Wan-Zhang's bound from three *** proposed results are based on the estimates related to the number of certain permutations and the value sets of non-permutation polynomials associated to the complete symmetric *** the author believes that there are still possibilities to improve the bounds and hence Wan-Zhang's bound.

关键词： Complete symmetric polynomial finite field permutation polynomial value set