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Novel high-performance element in the electromagnetic finite-element method——node-edge element

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Journal of Systems Engineering and electronics 2008年第5期19卷 878-881页

作者： sheng xinqing peng zhen Center for Electromagnetic Simulation School of Information Science and Technology Beijing Inst. of Technology Beijing 100081 P. R. China

It is known in the computational electromagnetics （CEM） that the node element has a relative wellconditioned matrix, but suffers from the spurious solution problem; whereas the edge element has no spurious solutions, but usually produces an ill-conditioned matrix. Particularly, when the mesh is over dense, the iterative solution of the matrix equation from edge element converges very slowly. Based on the node element and edge element, a node-edge element is presented, which has no spurious solutions and better-conditioned matrix. Numerical experiments demonstrate that the proposed node-edge element is more efficient than now-widely used edge element.

关键词： node-edge element node element edge element matrix condition number.

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新能源汽车管理与服务关键技术研究综述

中国公路学报 2024年第3期37卷 82-97页

作者：王震坡张普琛孙逢春张照生刘鹏北京理工大学机械与车辆学院北京100081 北京电动车辆协同创新中心北京100081

随着新能源汽车的推广应用,车辆规模爆发式增长的同时,在新能源汽车的产品端、运行端以及服务端出现了一系列问题:产品质量监管成效低、运行安全管控不精准、公共服务管理不全面。这些问题影响着新能源汽车的安全可靠运行,制约着新能源... 详细信息

随着新能源汽车的推广应用,车辆规模爆发式增长的同时,在新能源汽车的产品端、运行端以及服务端出现了一系列问题:产品质量监管成效低、运行安全管控不精准、公共服务管理不全面。这些问题影响着新能源汽车的安全可靠运行,制约着新能源汽车产业的发展,已经成为了行业的痛点。在汽车数字化的时代背景下,以大数据为核心,推动新能源汽车管理与服务关键技术的发展,是实现新能源汽车安全可靠高效应用、消除消费者安全焦虑、推动产业跨越式发展的必要支撑和保障。为了较为全面地综述该领域的技术水平和创新成果,从新能源汽车质量测评和溯源技术、新能源汽车安全运行管控和充电服务技术、新能源汽车行为分析辨识和碳核算技术3方面详细论述新能源汽车管理与服务关键技术的研究现状,并重点介绍了“运行大数据+”的新能源汽车“质量监管-运行管控-服务管理”技术体系,最后对目前新能源汽车管理与服务关键技术在产品质量监管、运行安全管控以及公共服务管理等方面存在的问题进行总结,对以大数据分析和挖掘为核心的新能源汽车“质量监测-运行管控-服务管理”技术进行展望。该综述可为新能源汽车管理与服务相关技术的进一步提高提供借鉴,也可为未来该领域技术的发展方向提供参考。

关键词：汽车工程新能源汽车综述管理服务质量测评安全监管

硫酸锌胶结珊瑚砂渗透特性试验及工程应用探讨

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岩土力学 2024年第7期45卷 2094-2104页

作者：王新志黄鹏雷学文文东升丁浩桢刘铠诚中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室湖北武汉430071 武汉科技大学城市建设学院湖北武汉430065 中国科学院大学北京100049

对松散珊瑚砂进行胶结处理以降低岛礁地层渗透性是促进生态岛淡水涵养的重要手段之一。为此,开展了硫酸锌胶结珊瑚砂的渗透试验,分析了不同浸泡时长、硫酸锌溶液浓度及初始干密度对胶结珊瑚砂渗透性的影响,采用干湿循环试验验证其耐久性... 详细信息

对松散珊瑚砂进行胶结处理以降低岛礁地层渗透性是促进生态岛淡水涵养的重要手段之一。为此,开展了硫酸锌胶结珊瑚砂的渗透试验,分析了不同浸泡时长、硫酸锌溶液浓度及初始干密度对胶结珊瑚砂渗透性的影响,采用干湿循环试验验证其耐久性,通过X射线衍射(X-ray diffraction,简称XRD)、扫描电镜(scanning electron microscope,简称SEM)、能量色散X射线光谱(energy dispersive spectrometer,简称EDS)及计算机断层扫描(computed tomography,简称CT)扫描研究微观胶结机制。结果表明:(1)硫酸锌胶结可将珊瑚砂渗透系数降低70.17%~95.79%;(2)干湿循环16次后,胶结处理36 h的珊瑚砂样品质量损失率不超过4%,渗透系数变化不超过1.0×10^(-3)cm/s,表明样品耐久性良好;(3)珊瑚砂和硫酸锌反应生成二水石膏与菱锌矿填充样品孔隙,使孔喉平均半径、配位数均减小,孔隙连通性显著下降。该技术可应用于岛礁吹填初期固砂防侵蚀、提高地基承载力、降低渗透性以促进地下淡水涵养和生态岛建设,具有重要的工程应用价值。

关键词：硫酸锌珊瑚砂渗透系数干湿循环岛礁

10B-doped MCP detector developed for neutron resonance imaging at Back-n white neutron source

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Nuclear Science and Techniques 2024年第8期35卷 58-68页

作者： Qiang Li Li‑Jiao Wang Jing‑Yu Tang Xiang‑Biao Qiu zhen Chen Mao‑Yuan Zhao Chang‑Jun Ning Kai Pan Wei Xu Tao Li Su‑peng Lu Han Yi Rui‑Rui Fan Chang‑Qing Feng Rong Zhang Xiao‑Yang Sun Qi An Hao‑Fan Bai Jiang‑Bo Bai Jie Bao Ping Cao Qi‑Ping Chen Yong‑Hao Chen Zeng‑Qi Cui An‑Chuan Fan Fan‑zhen Feng Min‑Hao Gu Chang‑Cai Han Zi‑Jie Han Guo‑Zhu He Yong‑Cheng He Yang Hong Yi‑Wei Hu Han‑Xiong Huang Wei Jiang Zhi‑Jie Jiang zheng‑Yao Jin Ling Kang Bo Li Gong Li Xiao Li Yang Li Jie Liu Rong Liu Shu‑Bin Liu Yi‑Na Liu Guang‑Yuan Luan Jie Ren Zhi‑Zhou Ren Xi‑Chao Ruan Zhao‑Hui Song Kang Sun Zhi‑Xin Tan sheng‑Da Tang Jin‑Cheng Wang peng‑Cheng Wang Zhao‑Hui Wang Zhong‑Wei Wen Xiao‑Guang Wu Xuan Wu Cong Xia Yong‑Ji Yu Guo‑Hui Zhang Hang‑Chang Zhang Lin‑Hao Zhang Qi‑Wei Zhang Xian‑peng Zhang Yu‑Liang Zhang Yue Zhang Zhi‑Yong Zhang Zhi‑Hao Zhou Ke‑Jun Zhu Chong Zou institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China State Key Laboratory of Particle Detection and electronics Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Dongguan Songshan Lake Future School Dongguan 523808China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China State Key Laboratory of Particle Detection and electronics University of Science and Technology of ChinaHefei 230026China North Night Vision Science and Technology(Nanjing)Research institute Co.Ltd Nanjing 211106China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China institute of Modern Physics Fudan UniversityShanghai 200433China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China china academy of Engineering Physics Institute of Nuclear Physics and ChemistryMianyang 621900China USTC archaeometry lab University of Science and Technology of ChinaHefei 230026China Northwest institute of Nuclear Technology Xi’an 710024China University of chinese academy of sciences Beijing 100049China china Shipbuilding Trading Co. LtdBeijing 100044China

Neutron resonance imaging(NRI)has recently emerged as an appealing technique for neutron *** complexity surpasses that of conventional transmission imaging,as it requires a high demand for both a neutron source and ***,the progression of NRI technology has been sluggish since its inception in the 1980s,particularly considering the limited studies analyzing the neutron energy range above *** white neutron source(Back-n)at the china Spallation Neutron Source(CSNS)provides favorable beam conditions for the development of the NRI technique over a wide neutron energy range from eV to ***-sensitive microchannel plates(MCP)have emerged as a cutting-edge tool in the field of neutron detection owing to their high temporal and spatial resolutions,high detection efficiency,and low *** this study,we report the development of a 10B-doped MCP detector,along with its associated electronics,data processing system,and NRI experiments at the *** heavy elements such as gold,silver,tungsten,and indium can be easily identified in the transmission images by their characteristic resonance peaks in the 1–100 eV energy range;the more difficult medium-weight elements such as iron,copper,and aluminum with resonance peaks in the 1–100 keV energy range can also be *** particular,results in the neutron energy range of dozens of keV(Aluminum)are reported here for the first time.

关键词： Neutron resonance imaging 10B doped MCP detector White neutron source Sample nuclide identification

重庆典型城区冬季碳质气溶胶的污染特征及来源解析

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环境科学 2024年第1期45卷 48-60页

作者：彭超李振亮向英王晓宸汪凌韬张晟翟崇治陈阳杨复沫翟天宇重庆市生态环境科学研究院重庆401147 中国环境科学研究院西南分院重庆401147 城市大气环境综合观测与污染防控重庆市重点实验室重庆401147 中国科学院重庆绿色智能技术研究院重庆400714 四川大学建筑与环境学院成都610065 北京大学环境科学与工程学院北京100871

于2021年1~2月在重庆典型城区万州区(WZ)、渝北区(YB)和双桥区(SQ)同步采集PM_(2.5)样品,分析冬季碳质气溶胶的污染特征、来源及潜在源区.结果表明,观测期间SQ的ρ(PM_(2.5))、ρ(OC)和ρ(EC)均值分别为(72.6±33.3)、(18.2±8.2)和(4.4... 详细信息

于2021年1~2月在重庆典型城区万州区(WZ)、渝北区(YB)和双桥区(SQ)同步采集PM_(2.5)样品,分析冬季碳质气溶胶的污染特征、来源及潜在源区.结果表明,观测期间SQ的ρ(PM_(2.5))、ρ(OC)和ρ(EC)均值分别为(72.6±33.3)、(18.2±8.2)和(4.4±1.7)μg·m^(-3),高于WZ[(67.2.30.3)、(17.2±7.4)和(5.1±2.4)μg·m^(-3)]和YB[(63.4±25.7)、(15.4±6.3)和(4.2.1.9)μg·m^(-3)].与清洁日相比,WZ污染日EC浓度及其对总碳的贡献率均涨幅最大(103.0%和8.1%),但OC/EC值下降最明显(-10.5%),表明WZ污染日碳质气溶胶的一次排放明显增强.观测期间SQ和YB的ρ(SOC)均值分别为(7.7±4.8)μg·m^(-3)和(6.9±2.8)μg·m^(-3),明显高于WZ[(4.5±1.9)μg·m^(-3)],表明二次转化对SQ和YB碳质气溶胶的影响相对较大.此外,与WZ不同,SQ和YB的SOC/OC值整体随PM_(2.5)浓度上升而增大,且SOC浓度与气溶胶液态水含量(AWC)、NO_(2)浓度和NOR值等均显著线性相关(P<0.01),表明通过液相反应生成含—NO_(2)官能团的SOC可能是SQ和YB碳质气溶胶浓度持续上升的主要因素.正定矩阵因子(PMF)解析结果表明,WZ的生物质/煤炭燃烧混合源贡献率(47.4%)明显高于YB(34.2%)和SQ(38.1%),而YB受汽油车排放和二次转化的影响较为突出.浓度权重轨迹分析(CWT)结果表明,各城区污染日碳质气溶胶主要受本地及其东北方向相邻城区(如长寿区)的影响.

关键词：碳质气溶胶污染过程二次有机碳来源解析重庆

珊瑚骨料种类和混杂纤维对珊瑚混凝土强度与断裂性能的影响

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Journal of Central South University 2024年第5期31卷 1592-1607页

作者：王振波刘伟康左建平韩宇栋李鹏飞郝如升 School of Mechanics and Civil Engineering China University of Mining and TechnologyBeijing 100083China State Key Laboratory for Fine Exploration and Intelligent Development of Coal Resources China University of Mining and TechnologyBeijing 100083China Central Research institute of Building and Construction MCC Group Co.Ltd.Beijing 100088China

海水珊瑚骨料混凝土(SCAC)由珊瑚礁砂石、海水等海洋地域性原材料与胶凝材料混合制备而成,在海洋国家的国防和基础设施建设中展现出缩短工期、降低成本、减少能源消耗的优势。但SCAC性脆易裂,珊瑚骨料的制约作用随着混凝土强度等级的提... 详细信息

海水珊瑚骨料混凝土(SCAC)由珊瑚礁砂石、海水等海洋地域性原材料与胶凝材料混合制备而成,在海洋国家的国防和基础设施建设中展现出缩短工期、降低成本、减少能源消耗的优势。但SCAC性脆易裂,珊瑚骨料的制约作用随着混凝土强度等级的提高而更加显著。本文探究了两种不同类型的珊瑚骨料对SCAC性能的影响,并将柔性的聚乙烯醇(PVA)纤维和刚性的钢纤维混杂,以期提升SCAC的强度、韧性与断裂性能。结果表明,含低强珊瑚骨料的SCAC抗压强度比含高强珊瑚骨料的SCAC抗压强度降低了30.8%(从55.6降至38.5 MPa),掺入纤维可以在一定程度上缓解骨料自身缺陷对SCAC强度的影响。此外,提出了一种新的本构模型来描述SCAC的应力-变形关系,模型预测结果与试验数据吻合较好。相比于不掺纤维的对照组,掺入0.1%、0.2%和0.3%PVA纤维的SCAC的断裂能分别提高了10%、49%和88%。在纤维用量相同时,混杂纤维组的断裂能比单掺纤维组高46%。

关键词：海水珊瑚骨料混凝土混杂纤维珊瑚骨料强度应力-应变曲线断裂性能

Nondestructive technique for identifying nuclides using neutron resonance transmission analysis at CSNS Back-n

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Nuclear Science and Techniques 2024年第1期35卷 178-187页

作者： sheng-Da Tang Yong-Hao Chen Jing-Yu Tang Rui-Rui Fan Qiang Li Gong Li Dong Liu zheng-Yao Jin Xing-Zhu Cui Tian-Xiang Chen Yi-Wei Yang Rong Liu Han Yi Yang Li zhen Yang Qi An Hao-Fan Bai Jiang-Bo Bai Jie Bao Ping Cao Qi-Ping Chen zhen Chen Zeng-Qi Cui An-Chuan Fan Chang-Qing Feng Fan-zhen Feng Ke-Qing Gao Min-Hao Gu Chang-Cai Han Zi-Jie Han Guo-Zhu He Yong-Cheng He Yang Hong Yi-Wei Hu Han-Xiong Huang Wei-Hua Jia Hao-yu Jiang Wei Jiang Zhi-jie Jiang Ling Kang Bo Li Chao Li Jia-Wen Li Xiao Li Jie Liu Shu-Bin Liu Guang-Yuan Luan Chang-Jun Ning Bin-Bin Qi Jie Ren Zhi-Zhou Ren Xi-Chao Ruan Zhao-Hui Song Kang Sun Zhi-Xin Tan Li-Jiao Wang peng-Cheng Wang Zhao-Hui Wang Zhong-Wei Wen Xiao-Guang Wu Xuan Wu Li-Kun Xie Yong-Ji Yu Guo-Hui Zhang Lin-Hao Zhang Mo-Han Zhang Qi-Wei Zhang Xian-peng Zhang Yu-Liang Zhang Yue Zhang Zhi-Yong Zhang Mao-Yuan Zhao Lu-Ping Zhou Zhi-Hao Zhou Ke-Jun Zhu Sino-French institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China institute of High-Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Particle Detection and electronics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Particle Detection and electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China USTC Archaeometry Laboratory University of Science and Technology of ChinaHefei 230026China institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China Northwest institute of Nuclear Technology Xi’an 710024China University of chinese academy of sciences Beijing 100049China

Nondestructive and noninvasive neutron assays are essential applications of neutron *** resonance transmission analysis(NRTA)is a powerful nondestructive method for investigating the elemental composition of an *** back-streaming neutron line(Back-n)is a newly built time-of-flight facility at the china Spallation Neutron Source(CSNS)that provides neutrons in the eV to 300 MeV range.A feasibility study of the NRTA method for nuclide identification was conducted at the CSNS Back-n via two test *** results demonstrate that it is feasible to identify different elements and isotopes in samples using the NRTA method at *** study reveals its potential future applications.

关键词： CSNS White neutron beam NRTA Nuclide identification Nondestructive method

Comparative study on the removal technologies of 2-methylisoborneol(MIB) in drinking water

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Journal of Environmental sciences 2006年第1期18卷 47-51页

作者： LIANG Cun-zhen WANG Dong-sheng GE Xiao-peng YANG Min SUN Wei State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Beijing 100085 China Department of Environmental Engineering Beijing Institute of Petrochemical Technology Beijing 102617 China

Removal of 2-methylisoborneol （MIB） in drinking water by ozone, powdered activated carbon （PAC）, potassium permanganate and potassium ferrate was investigated. The adsorption kinetics of MIB by both wood-based and coat-based PACs show that main removal of MIB occurs within contact time of 1 h. Compared with the wood-based PAC, the coat-based PAC evidently improved the removal efficiency of MIB. The removal percentage of trace MIB at any given time for a particular carbon dosage was irrelative to the initial concentration of MIB. A series of experiments were performed to determine the effect of pH on the ozonation of MIB. The results show that pH has a significant effect on the ozonation of MIB. It is conclusive that potassium permanganate and potassium ferrate are ineffective in removing the MIB in drinking water.

关键词： odor MIB ozonation powdered activated carbon potassium permanganate potassium ferrate

Single Mode Simulation Calculation of Oscillating Buoy Wave Energy Converter with A Slider

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china Ocean Engineering 2020年第4期34卷 547-557页

作者： XIAO Lei YOU Ya-ge WANG zhen-peng ZHANG Ya-qun HUANG Shuo WANG Wen-sheng Guangzhou institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640China Southern Marine Science and Engineering Guangdong Laboratory Guangzhou 511458China Key Laboratory of Renewable Energy Chinese Academy of SciencesGuangzhou 510640China Innovation academy of South china Sea Ecology and Environmental Engineering Chinese Academy of SciencesGuangzhou 510640China University of chinese academy of sciences Beijing 100049China

This paper presents an oscillating slider wave energy device which is based on a seabed anchoring and uses eagle beak as the *** self-compiled program uses the boundary element theory based on the simple Green’s function to solve the wave forces and hydrodynamic *** the equation of motion,the oscillation of the float and the capture width ratio are obtained by the modal *** influences of the shape of the eagle beak,the angle of the slider and the wave heading on the capture ability of the device are *** to the calculation results and the wave resources in the sea area,the optimal shape of the eagle beak and external damping can be selected to maximize the wave energy capture capability.

关键词： wave energy converter(WEC) Sharp Eagle hydrodynamic calculation eagle beak