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小型泵站进水池改造为肘形进水流道水力性能研究

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中国农村水利水电 2024年第9期 130-136页

作者：徐鹏飞朱波郭瑞朱昊段鸿飞徐磊淮安市水利勘测设计研究院有限公司江苏淮安223001 扬州大学水利科学与工程学院江苏扬州225009 淮安市水利工程建设管理服务中心江苏淮安223005

为了解决淮安市徐溜电灌站水泵进水流态差导致机组振动和水泵装置运行效率低下等问题,基于该电灌站的设计参数,采用三维湍流流动数值模拟方法对进水池及其改造为肘形进水流道的水力性能进行了研究,对两种进水型式时的泵装置能量性能进... 详细信息

为了解决淮安市徐溜电灌站水泵进水流态差导致机组振动和水泵装置运行效率低下等问题,基于该电灌站的设计参数,采用三维湍流流动数值模拟方法对进水池及其改造为肘形进水流道的水力性能进行了研究,对两种进水型式时的泵装置能量性能进行预测计算,并对改造前后的流道及泵装置的流态和性能进行比较分析。研究结果表明:该站进水池具备改造为肘形进水流道的条件;原进水池方案的流道水头损失大、池内流态紊乱,改造后的肘形进水流道水头损失显著减小、流场平顺无旋涡,水力性能大幅度提升;改造后的泵装置水力性能较改造前明显提升,设计流量下泵装置效率提升5%以上。改造后现场水泵机组整体运行稳定,表明将开敞式进水池改造为肘形进水流道是成功的,可为同类型的小型泵站的建设和改造提供参考。

关键词：小型泵站进水池肘形进水流道水力性能

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职业教育本科生职业生涯困扰的成因、表现及纾解途径剖析

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教育探索 2024年第9期 51-56页

作者：卢伟许鹏飞滕飞南京工业职业技术大学交通工程学院南京210023 南京工业职业技术大学学生工作处南京210023 南京工业大学马克思主义学院南京211816

从职业教育本科生职业生涯困扰的本质内涵出发,将职业教育本科生职业生涯困扰的成因概括为职业教育本科生面临的职业难题、疑虑或困境阻碍了其职业需要的满足。当前职业教育本科生职业生涯困扰的主要表现为:技能立业意愿不强加剧毕业求... 详细信息

从职业教育本科生职业生涯困扰的本质内涵出发,将职业教育本科生职业生涯困扰的成因概括为职业教育本科生面临的职业难题、疑虑或困境阻碍了其职业需要的满足。当前职业教育本科生职业生涯困扰的主要表现为:技能立业意愿不强加剧毕业求职竞争焦虑、职业教育学历标签造成职业生活交往信心不足、本科层次教育获得感不强引起技能报国理想信念迟疑等方面。纾解职业教育本科生职业生涯困扰是在推进全面推动经济高质量发展中创造更多的公平就业机会和职业待遇,在推进职业教育现代化治理中培育更强的职业教育本科生职业能力,在加强和改进思想政治教育中树立更优的社会职业价值观等路径中创造纾解困扰的综合条件。

关键词：困扰职业教育本科生职业生涯困扰职业需要纾解途径

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基于无人机直播联动的养殖动物视觉识别系统

计算机系统应用 2024年第6期33卷 126-132页

作者：叶扬徐精文徐鹏飞四川农业大学资源学院成都611134

对养殖动物的高效识别是畜牧养殖场开展各类精准养殖的基础,需要建设相应识别系统做支撑.本文所设计系统采用无人机直播联动方式进行样本采集和巡检识别,既能将视频实时上传到数据中心,又比无人机普通拍摄具有更少的小目标和遮挡问题发... 详细信息

对养殖动物的高效识别是畜牧养殖场开展各类精准养殖的基础,需要建设相应识别系统做支撑.本文所设计系统采用无人机直播联动方式进行样本采集和巡检识别,既能将视频实时上传到数据中心,又比无人机普通拍摄具有更少的小目标和遮挡问题发生,在此基础上,系统选用YOLOv7算法模型进行动物行为和数量的识别,并对YOLOv7算法模型优化和轻量化,以提升识别精度和降低系统负载,最后将识别数据输出到标准接口供各类精准养殖程序便捷调用.系统既适应养殖场的场景需求又兼顾系统的高效运行,能为养殖场实施各类精准养殖提供统一数据支持,降低重复设计成本和分散管理成本.

关键词：无人机直播养殖动物视觉识别 YOLOv7 轻量化

Influences of meridional flowpath on the performance of swept blade in an axial compressor stage

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航空动力学报 2015年第8期30卷 1875-1887页

作者： YU Xian-jun xu peng-fei ZHANG Yi-fei LIU Bao-jie School of Energy and Power Engineering Beiiing University of Aeronautics and Astronautics Beijing 100191 China National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Energy and Power EngineeringBeijing University of Aeronautics and Astronautics Beijing 100191 China Collaborative Innovation Center for Advanced Aero-Engine Beijing 100191 China

A series of numerical simulations were conducted in both a 1.5stage axial compressor model and a simplified planar cascade *** cases with different blade sweep schemes in the cascade model were simulated with free-slip endwalls to minimize the influence of endwall 3-D(three-dimensional)*** results obtained in the cascade model were discussed at first for getting a clear insight into the effects of blade sweep without other *** then the simulation results of the 1.5stage compressor model were discussed *** discussions focused on the influences of different meridional flowpath designs,*** mid radius(CMR)design,constant outer radius(COR)design and constant inner radius(CIR)design,on the performance of the swept *** results showed that the most critical effect produced by blade sweep was attributed to the redistribution of local mass-flow-rate in blade spanwise *** change of meridional flowpath did not change the mass-flow-rate redistribution ***,the trends for local mass-flow-rate redistribution in compressor stage model showed some discrepancies compared with the results shown in the planar cascade model.

关键词：航空航空动力学航空发动机发动原理

银纳米三角传感阵列在生化物质检测方面的应用分析

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实验室检测

实验室检测 2024年第5期2卷 22-25页

作者：周锴文徐鹏飞哈尔滨工程大学哈尔滨150001 哈尔滨工业大学哈尔滨150006

在纳米技术发展推动下,银纳米材料凭借其催化性能、导电性能、光学特性,被广泛应用在传感领域中。银纳米三角传感阵列在多组分同时检测、高灵敏度等性能支撑下,成为生化物质检测领域的研究热点。本文基于此,总结银纳米三角的合成方法、... 详细信息

在纳米技术发展推动下,银纳米材料凭借其催化性能、导电性能、光学特性,被广泛应用在传感领域中。银纳米三角传感阵列在多组分同时检测、高灵敏度等性能支撑下,成为生化物质检测领域的研究热点。本文基于此,总结银纳米三角的合成方法、特性以及传感阵列的研究进展,并重点介绍比色传感阵列、表面增强拉曼散射等技术在生化物质检测中的实际应用,为相关领域的研究和实践提供有益的参考。

关键词：银纳米三角传感阵列生化物质检测比色传感表面增强拉曼散射

A Parametric Survey of the CME Triggering Process by Numerical Simulations

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Chinese Journal of Astronomy and Astrophysics 2005年第6期5卷 636-644页

作者： Xiao-Yan xu peng-fei Chen Cheng Fang Department of Astronomy Nanjing University Nanjing 210093

Observations indicate that solar coronal mass ejections （CMEs） are closely associated with reconnection-favored flux emergence, which was explained in the emerging flux trigger mechanism for CMEs by Chen ＆ Shibata based on numerical simulations. We present a parametric survey of the triggering agent： its polarity orientation, position, and the amount of the unsigned flux. The results suggest that whether a CME can be triggered depends on both the amount and location of the emerging flux, in addition to its polarity orientation. A diagram is presented to show the eruption and non-eruption regimes in the parameter space. The work is aimed at providing useful information for the space weather forecast.

关键词： Sun coronal mass ejections (CMEs)-Sun filaments

Catalytically generated noncovalent ammonium dienolate:a versatile platform for the development of organocatalytic asymmetric cascade reactions

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Science China Chemistry 2024年第8期67卷 2524-2546页

作者： Jun-Bing Lin Dong-Sheng Ji peng-fei xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China Shaanxi Key Laboratory of Chemical Reaction Engineering College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China

Organocatalytic cascade reactions represent a powerful strategy for the rapid construction of complex chiral molecules with multiple stereocenters from simple substrates under mild conditions. The intriguing structural feature and diverse reactivity of catalytically generated dienolate species render them competent and versatile intermediates for the development of practical and valuable cascade reactions. Over the past years, a plethora of innovative and pioneering noncovalent ammonium dienolatemediated cascade reactions have been designed and implemented under the catalysis of chiral organocatalysts, making dienolate activation a general, robust, and complementary method for the functionalization of unsaturated carbonyl compounds and related substances. This review illustrates the recent advances in organocatalytic noncovalent ammonium dienolate-mediated cascade reactions(mainly from 2010 to 2023), including the cascade transformations of ammonium dienolates directly generated from unsaturated ketone/aldehyde, ester/lactone/azlactone, amide/lactam/pyrazolone/oxindole, and alkylidene nitrile compounds. The contents are arranged based on the reaction types of the ammonium dienolates, with an emphasis on cascade 2,5-, 3,5-, and 4,5-difunctionalizations of these intermediates. Furthermore, other cascade reactions involving the 1,3-, 2,3-, and even more complex 3,4,5-reactivities of ammonium dienolates were also discussed. The reaction pathway, reaction stereoinduction, and synthetic applications of the ammonium dienolate-mediated cascade reactions were highlighted throughout the article. As a stimulating and ever-growing research area, the organocatalytic noncovalent ammonium dienolate-mediated cascade reactions are expected to continue demonstrating their magic power for constructing chiral targets in the future and further expanding the boundaries of asymmetric catalysis.

关键词： organocatalysis asymmetric catalysis ammonium dienolate cascade reaction difunctionalization

A detection algorithm of spatter on welding plate surface based on machine vision

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Optoelectronics Letters 2019年第1期15卷 52-56页

作者： XIA Xin-miao JIANG Zhao-liang xu peng-fei School of Mechanical Engineering Shandong University Key Laboratory of High Efficiency and Clean Machine Manufacturing Ministry of Education Shandong University

Welding spatter seriously affects the surface quality of the product. Aiming at the automatic detection problem of spatter on welding plate surface, an in-situ detection algorithm of welding spatter based on machine vision is designed. In the extraction process of the welding spatter, the two-dimensional Fourier transform is adopted to obtain the frequency and phase information of image, and the elliptical high-pass filter is introduced to filter the low-frequency signal. The experimental results show that the proposed algorithm has higher extraction rate and extraction accuracy rate of welding spatter than the threshold method, the rectangular high-pass filter and the Canny operator, and it has the characteristics of high efficiency, high precision, and good robustness.

关键词： detection algorithm spatter surface

Cation-Dipole Interaction-Induced Coacervate Underwater Adhesives in Natural Seawater

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Chinese Journal of Polymer Science 2024年第7期42卷 984-991,I0009页

作者： xu-fei Liu Chong-Rui Zhang Hua-Wen peng Qiang Zhao Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China

Significant progress has been made in wet adhesives for low salinity water,but exploration of general ionic adhesives for natural seawater is less developed because the high salinity could weaken interfacial bonding and shields electrostatic interactions,resulting in adhesion ***,the design of adhesives for natural seawater represents challenges less ***,a cationic polyelectrolyte(PECHIA)containing imidazolacetonitrile unit was explored to prepare adhesives enabled by natural *** combining the ion shielding effect with the“cation-dipole”interactions between PECHIA chains,aqueous solution of the PECHIA underwent coacervation and self-crosslinking in natural seawater,allowing for underwater adhesion to various substrates in *** instantaneous lap-shear and tensile adhesion strengths are 47 and 119 kPa,respectively,while the cured adhesive shows~739 k Pa tensile adhesion in natural *** design of PECHIA enables wet adhesives viable for applications in the diversified scenarios of natural seawater.

关键词： Coacervate Underwater adhesives Seawater Cation-dipole interaction