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Design and 3D printing of porous cavity insulation structure for ultra-high electrical withstanding capability

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High Voltage 2023年第4期8卷 717-727页

作者： Xiong Yang Guangyu Sun baipeng song Wenhu Han Chao Wang Wendong Li Shu Zhang Falun song Fangzheng Zou Guanjun Zhang State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical EngineeringXi'an Jiaotong UniversityXi'anChina Ecole Polytechnique Fédérale de Lausanne(EPFL) Swiss Plasma Center(SPC)LausanneSwitzerland Institute of Applied Electronics China Academy of Engineering PhysicsMianyangChina

Vacuum-dielectric interface is the most vulnerable part of vacuum insulation systems where surface electrical breakdown is prone to happen,hence severely restricts the development of advanced electro-vacuum devices with large capacity and its ***,a direct and effective way to improve vacuum surface insulation is to alleviate the initiation and development of multipactor *** by this approach,the authors report a 3D-printed insulation structure designed with a millimetrescale surface cavity covered by periodic through-pore array via stereolithography,exhibiting remarkable multipactor suppression and flashover threshold improvement,well outperforming the conventional flashover mitigation *** and simulations demonstrate that electrons in the multipactor region pass through-pores and are unlikely to escape from the cavity,hence no longer participate in the above-surface multipactor process,and eventually improve flashover *** proposed approach provides new inspiration for the design of advanced insulators featuring ultrahigh electrical withstanding capability and brings up new insight into pertinent industrial applications.

关键词： insulation electrical hence

气液混相水中脉冲放电过氧化氢生成规律的研究

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高电压技术 2019年第12期45卷 4130-4136页

作者：张梦瑶温嘉烨李元宋佰鹏张冠军西安交通大学电力设备电气绝缘国家重点实验室

水中脉冲放电技术可产生过氧化氢(H2O2)等高氧化电位的活性物质,在工业废水处理、生物灭菌和医疗领域具有广阔的应用前景。为此采用介质涂覆的柱-筒电极结构,在气/液混相条件下,探究了通气种类(氧气和氩气)与气体流速对H2O2生成速率和光... 详细信息

水中脉冲放电技术可产生过氧化氢(H2O2)等高氧化电位的活性物质,在工业废水处理、生物灭菌和医疗领域具有广阔的应用前景。为此采用介质涂覆的柱-筒电极结构,在气/液混相条件下,探究了通气种类(氧气和氩气)与气体流速对H2O2生成速率和光-电特性的影响。实验结果表明通气时气泡内部的微放电有利于活性物质生成,不同气体流速会影响H2O2的生成速率。过高的气体流速会导致液相扰动影响放电通道形成,降低H2O2产率。不同通气种类对H2O2生成也有较大影响,由于氧气电子亲和能较大,相比氩气更易吸附电子,导致氧气气流经过放电通道时出现通道“截断”现象。氧气发生放电反应生成氧化电位较高的自由氧原子与水剧烈反应生成羟基自由基(·OH)从而使H2O2的产率提升较为明显。在该研究条件下氧气体积流量为0.6 L/min时,H2O2生成速率最大;通入氩气时,上升气流在液面处积聚大量的气泡,气泡内放电现象较为明显,但与通氧气相比,通氩气对放电过程中H2O2生成速率提升较小,该研究条件下氩气体积流量为0.3 L/min时H2O2生成速率最大。

关键词：水中放电过氧化氢气液混相放电流注放电火花放电

3D打印构筑随机表面微结构调控绝缘的真空沿面闪络特性

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高电压技术 2022年第12期48卷 4739-4749页

作者：杨雄宋佰鹏杨宁黄昆孙光宇张冠军西安交通大学电力设备电气绝缘国家重点实验室西安710049 中国电力科学研究院有限公司电网环境保护国家重点实验室武汉430074

表面形貌调控被认为是提升真空绝缘闪络电压的有效举措之一,但常用表面粗化技术的效果具有较高的随机性,可控的调控方法和制备技术仍是亟需解决的技术难题。为此,采用基于路径追踪算法的仿真手段获得二次电子产率(secondary electron yi... 详细信息

表面形貌调控被认为是提升真空绝缘闪络电压的有效举措之一,但常用表面粗化技术的效果具有较高的随机性,可控的调控方法和制备技术仍是亟需解决的技术难题。为此,采用基于路径追踪算法的仿真手段获得二次电子产率(secondary electron yield,SEY)可调的随机微结构表面;利用立体光固化成型3D打印技术实现了随机微表面结构的精准制备;通过闪络电压及表面电荷特性的表征手段,结合仿真结果,系统分析了表面形貌参数对闪络的影响。结果表明:改变表面形貌参数可以设计出SEY可调的微结构表面;分析认为,微结构通过影响电子与材料表面的碰撞过程,对二次电子倍增及表面电荷积聚行为产生影响,进而对闪络电压产生影响;改变表面形貌参数可以有效调控绝缘子的闪络强度,SEY越小闪络电压越高(最大差距达92.7%)。研究成果有望为真空绝缘系统中的固体绝缘设计提供新的思路。

关键词：真空闪络表面随机微结构 3D打印二次电子发射系数表面电荷

The Persistence and Zonal Scale of Atmospheric Dipolar Modes

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Advances in Atmospheric Sciences 2024年第3期41卷 478-492页

作者： Jie song State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China

This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes(DMs). Results from the daily data of ERA5 and the long-term output of an idealized atmospheric model show that the atmospheric DMs with a broader(narrower) zonal scale dipolar structure possess a longer(shorter) persistence. A detailed vorticity budget analysis indicates that the persistence of a hemispheric-scale DM(1/1 DM) and a regional or sectoral DM(1/8 DM) in the model both largely rely on the persistence of the nonlinear eddy forcing. Linear terms can indirectly reduce the persistence of the anomalous nonlinear eddy forcing in a 1/8 DM by modifying the baroclinicity via the arousal of anomalous vertical motions. Therefore, the atmospheric DMs with a broader(narrower) zonal scale possess a longer(shorter) persistence because the effects of the linear terms are less(more) pronounced when the atmospheric DMs have better(worse) zonal symmetry. Further analyses show that the positive eddy feedback effect is weak or even absent in a 1/8DM and the high-frequency eddy forcing acts more like a concomitant phenomenon rather than a leading driving factor for a 1/8 DM. Thus, the hemispheric-scale DM and the regional or sectoral DMs are different, not only in their persistence but also in their dynamics.

关键词： NAM NAO eddy feedback persistence linear term

Identification of Linear Systems Using Binary Sensors with Random Thresholds

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Journal of Systems Science & Complexity 2024年第3期37卷 907-923页

作者： HUANG Zhiyong song Qijiang School of Mathematics Renmin University of ChinaBeijing 100872China School of Mathematics Sino-French InstituteRenmin University of ChinaBeijing 100872China

In this paper,the problem of identifying autoregressive-moving-average systems under random threshold binary-valued output measurements is *** the help of stochastic approximation algorithms with expanding truncations,the authors give the recursive estimates for the parameters of both the linear system and the binary *** reasonable conditions,all constructed estimates are proved to be convergent to the true values with probability one,and the convergence rates are also established.A simulation example is provided to justify the theoretical results.

关键词： α-mixing binary sensor quantized system stochastic approximation stochastic thresh-old strongly consistent system identification

真空高功率微波介质窗表面击穿破坏现象的研究进展

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强激光与粒子束 2012年第1期24卷 16-23页

作者：郝西伟宋佰鹏张冠军秋实黄文华秦风金晓西安交通大学电力设备电气绝缘国家重点实验室西安710049 西北核技术研究所西安710024 中国工程物理研究院应用电子学研究所四川绵阳621900

综述了国内外真空中高功率微波(HPM)下介质窗表面击穿问题的研究现状和进展。在介质窗表面击穿实验研究方面,介绍了国外最具代表性的研究成果,给出了介质窗材料表面及内部的破坏发展规律,并提出相应的理论模型。在理论仿真方面,重点介... 详细信息

综述了国内外真空中高功率微波(HPM)下介质窗表面击穿问题的研究现状和进展。在介质窗表面击穿实验研究方面,介绍了国外最具代表性的研究成果,给出了介质窗材料表面及内部的破坏发展规律,并提出相应的理论模型。在理论仿真方面,重点介绍了国外在运用蒙特卡罗(Monte Carlo)程序和PIC模型对认识HPM下介质窗表面倍增放电机理上做出的突出贡献,给出了HPM下介质窗表面电子在不同影响因素下的运行状态,并提出了一个理论模型,从本质上解释了倍增电子数目和表面静电场以微波频率的2倍振荡的原因。介绍了目前几种可有效抑制介质窗表面微波击穿的技术手段。

关键词：高功率微波介质窗表面击穿蒙特卡罗模拟 PIC模拟倍增放电

The learning curve for transurethral enucleation with bipolar energy for benign prostate hyperplasia:a single-surgeon experience of 494 patients

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Asian Journal of Andrology 2024年第3期26卷 288-294页

作者： Byeongdo song Sang Hun song Seong Jin Jeong Department of Urology Seoul National University Bundang HospitalSeongnam 13620Korea Department of Urology Seoul National University College of MedicineSeoul 03080Korea

This study was performed to investigate the learning curve of transurethral enucleation with bipolar energy(TUEB)for benignprostatic *** study involved 494 consecutive patients who underwent TUEB for benign prostatic hyperplasia fromAugust 2018 to March 2022 by one surgeon(SJJ,Seoul National University Bundang Hospital,Seongnam,Korea).The patientswere followed up at 1 week,1 month,3 months,and 6 months *** evaluate the learning curve of TUEB,perioperativeparameters including the enucleation ratio(enucleated tissue weight/transitional zone volume),TUEB efficiency(enucleatedtissue weight/operation time),and enucleation efficiency(enucleated tissue weight/enucleation time)were *** and postoperative complications were also assessed,including the International Prostate Symptom Score(IPSS),IPSSquality-of-life(QoL)score,and uroflowmetry *** patients’median age was 72(interquartile range[IQR]:66–78)years,and the estimated prostate volume and transitional zone volume were 63.0(IQR:46.0–90.6)ml and 37.1(IQR:24.0–60.0)ml,*** enucleation ratio,TUEB efficiency,and enucleation efficiency were 0.60(IQR:0.46–0.54)g ml−1,0.33(IQR:0.22–0.46)g min−1,and 0.50(IQR:0.35–0.72)g min−1,respectively,plateauing after 70 *** functional outcomes,including total IPSS,IPSS QoL score,and uroflowmetry outcomes,significantly improved at 6 months after TUEB(all P<0.05),but without significant differences over the learning ***-five(13.2%)patients developed complications after TUEB,21.5%of whom experienced major complications(Clavien–Dindo grade≥3).The rate of major complications declined as the number ofTUEB cases increased(P=0.013).Our results suggest that the efficiency of TUEB stabilized within 70 procedures.

关键词： benign prostate hyperplasia learning curve perioperative efficiency prostate transurethral enucleation with bipolar energy

Self-healing Ga-based liquid metal/alloy anodes for rechargeable batteries

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Nano Research 2024年第3期17卷 1366-1383页

作者： Meijia song Zhonghua Zhang School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212000China Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJingshi Road 17923Jinan 250061China

With the rapid development of electronics,electric vehicles,and grid energy storage stations,higher requirements have been put forward for advanced secondary *** metal/alloy electrodes have been considered as a promising development direction to achieve excellent electrochemical performance in metal-ion batteries,due to their specific advantages including the excellent electrode kinetics and self-healing ability against microstructural electrode *** conventional liquid batteries,high temperatures are needed to keep electrode liquid and ensure the high conductivity of molten salt electrolytes,which also brings the corrosion and safety ***-based metal/alloys,which can be operated at or near room temperature,are potential candidates to circumvent the above *** this review,the properties and advantages of Ga-based metal/alloys are ***,Ga-based liquid metal/alloys as anodes in various metal-ion batteries are reviewed in terms of their self-healing ability,battery configurations,working mechanisms,and so ***,some views on the future development of Ga-based electrodes in batteries are provided.

关键词： metal-ion batteries Ga-based liquid metal/alloy anodes self-healing capability room temperature

A Novel Three-stage Tectonic Model for Mississippi Valleytype Zn-Pb Deposits in Orogenic Fold-and-Thrust Belts

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 843-849页

作者： song Yucai SinoProbe Laboratory Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China

Mississippi Valley-type(MVT) Zn-Pb deposits predominantly form within both orogenic forelands and fold-andthrust belts, yet the mineralization process within the latter tectonic setting remains inadequately understood. This study, through a comprehensive review of MVT deposits across global fold-and-thrust belts, introduces a novel model elucidating the mineralization process in the context of tectonic belt evolution. It is demonstrated that during the stage Ⅰ, regional compression is introduced by early stages of plate convergence, causing the folding and thrusting and creating structural or lithological traps such as evaporite diapirs and unconformity-related carbonate dissolution-collapse structures. Thereafter, in stage Ⅱ, hydrocarbons begin to migrate and accumulate within these traps, where reduced sulfur is generated through thermochemical or bacterial sulfate reduction concurrent with or preceding Zn-Pb mineralization. In the subsequent stage Ⅲ, as plate convergence persists, the regional stress transitions from compression to transpression or extension. Under these conditions, steeply-dipping extensional faults are generated, facilitating the ascent of metalliferous brines into early-formed structural or lithological traps. Precipitation of Zn and Pb sulfides occurs through the mixing of Zn-Pb-transporting fluids with pre-existing reduced sulfur or by interaction with hydrocarbons.

关键词： Mississippi Valley-type Zn-Pb deposits fold-and-thrust belts tectonic model structural or lithological traps extensional faults