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Journal of Thermal Science 2024年第1期33卷 101-113页

作者： yuan baoqiang WANG Wei XIN Gongming DU Wenjing School of Energy and Power Engineering Shandong UniversityJi'nan 250061China

Large eddy simulations have been conducted to study upward transitional flows and heat transfer characteristics of supercritical CO_(2) in a vertical mini-channel.The numerical simulation was carried out on a modified buoyantPimpleFOAM solver in OpenFOAM 7,and was verified using experiment data.Numerical results indicate that increasing the Grashof numbers can reduce the flow stability and make the flow transition earlier.There are four stages of heat transfer in the transition process,i.e.,weakened,improved,recovered and normal heat transfer.These heat transfer phenomena in the transition process were explained from three perspectives:thermal boundary layer theory,turbulent transport and pseudo-boiling theory.Heat transfer enhancement during transition is related to the transport of supercritical molecular clusters,and these molecular clusters are regarded as pseudo-bubbles in pseudo-boiling theory.The flow pattern of the pseudo-phases in the dia-Widom process contains single-phase flow,steady pseudo-film flow,unsteady pseudo-film flow,partial pseudo-bubbles flow and flocculent pseudo-film flow.Pseudo-bubbles have similar behaviors to subcritical bubbles,i.e.,break-up,deformation,condensation and coalescence.Relevant researches in this work are favorable for understanding the heat transfer mechanism of supercritical fluids during flow transition.

关键词： supercritical heat transfer large eddy simulation transition pseudo-boiling

Analysis and Modeling of Calendar Aging and Cycle Aging of LiCoO_(2)/Graphite Cells

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Journal of Thermal Science 2024年第3期33卷 1109-1118页

作者： WANG Wei yuan baoqiang SUN Qie WENNERSTEN Ronald Institute of Thermal Science and Technology Shandong UniversityJi’nan250061China School of Energy and Power Engineering Shandong UniversityJi’nan250061China Institute for Advanced Science and Technology Shandong UniversityJi’nan250061China

Lithium-ion batteries are used in a wide range of applications.However,their cycle life suffers from the problem of capacity fade,which includes calendar and cycle aging.The effects of storage time,temperature and partial charge-discharge cycling on the capacity fade of Li-ion batteries are investigated in this study.The calendar aging and cycle aging are presented based on the storage and cycling experiment on LiCoO_(2)/graphite cells under different storage temperature and different ranges of state of charge(SOC).Based on the measurement data,a one-component and a double-component aging model are presented to respectively describe the capacity fade caused by calendar and cycle aging.The calendar aging of LiCoO_(2)/graphite batteries is mainly affected by temperature and SOC during the storage.Mean SOC and change in SOC(ΔSOC)are the main factors affecting battery degradation during cycling operation.

关键词： Lithium-ion battery LiCoO_(2)(LCO)/graphite calendar aging cycle aging lifetime model

A multicenter retrospective cohort study of ketogenic diet therapy in 481 children with infantile spasms

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Acta Epileptologica 2022年第1期5卷 42-49页

作者： yuanzhen Ye Dan Sun Hua Li Jianmin Zhong Rong Luo Baomin Li Dengna Zhu Dan Li Shaoping Huang Yuwu Jiang Nong Xiao Yucai Chen Yuqin Zhang Mei Yu Xiaoyun Shen Li Gao Guo Zheng Congmin Zhao baoqiang yuan Jianxiang Liao Jiong Qin CAAE KD group Shenzhen Children's Hospital Shenzhen 518038China Wuhan Children's Hospital Wuhan 430019China Guangdong 999 Brain Hospital Guangzhou 510515China Jiangxi Provincial Children's Hospital Nanchang 330006China West China Second University Hospital Sichuan UniversityChengdu 610044China Qilu Hospital of Shandong University Jinan 250063China Third Affiliated Hospital Zhengzhou UniversityZhengzhou 450015China The Second Affiliated Hospital of Xi’an Jiaotong University Xian 710004China Peking University First Hospital Beijing 100034China Children's Hospital of Chongqing Medical University Chongqing 400015China Children^Hospital of Shanghai Shanghai 20006China Tianjin Children's Hospital Tianjing 300134China Henan Provincial People's Hospital Zhengzhou 451161China Nanjing Children's Hospital Nanjing 210008China Xinqiao Hospital Army Medical UniversityChongqing 400037China The Affiliated Hospital of Xuzhou Medical University Xuzhou 221004China Peking University Peopled Hospital Beijing 100044China

Background:Ketogenic diet(KD)therapy is one of the main treatments for drug-resistant epilepsy.However,the KD therapy has been applied in only a small number of infantile spasm cases.In this large multicenter study,we investigated the efficacy of KD therapy in the treatment of infantile spasms.Methods:In this retrospective,multicenter cohort study,clinical data from main epilepsy centers were analyzed.Patients were classified into different groups according to age,type of drug and whether glucocorticoid was used before initiation of KD.Results:From October 2014 to March 2020,481 patients(308 males and 173 females)with infantile spasms were treated with the KD therapy.The age of the patients ranged from 2 months to 20 years,with a mean age of 1 year and 10 months.The number of anti-seizure medications(ASMs)used before KD initiation ranged 0-6,with a median of 3.In different time from initiation(1,3,6,and 12 months),the rates of seizure freedom after KD were 6.9,11.6;16.0 and 16.8%,respectively(x^(2)=27.1772,P0.05).Two hundred and eighteen patients(45.3%)failed to respond to c

关键词： Epilepsy Infantile spasms Ketogenic diet Adverse events Effectiveness rate West syndrome Multicenter study Retrospective Cohort

射频感应热等离子体制备锂离子电池硅基负极材料的研究进展

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过程工程学报 2024年第5期24卷 501-513页

作者：杨宗献董元江刘畅金化成丁飞李保强白柳杨袁方利河南大学化学与分子科学学院河南开封475004 中国科学院过程工程研究所多相复杂系统国家重点实验室北京100190 中国科学院大学化学工程学院北京100049 黄淮学院能源工程学院河南驻马店463800

硅负极凭借其高理论比容量被认为是最具有应用前景的负极材料之一,但脱嵌锂过程中较大的体积变化严重限制了其实际应用。通过将硅负极纳米化,能够显著缓解体积效应、改善导电性及提高稳定性。射频感应热等离子体具有高温、瞬冷、可控、... 详细信息

硅负极凭借其高理论比容量被认为是最具有应用前景的负极材料之一,但脱嵌锂过程中较大的体积变化严重限制了其实际应用。通过将硅负极纳米化,能够显著缓解体积效应、改善导电性及提高稳定性。射频感应热等离子体具有高温、瞬冷、可控、连续等优点,是制备高纯纳米硅基负极的重要手段。本工作综述了射频感应热等离子体制备锂离子电池硅基负极材料的研究进展。首先对热等离子体技术进行简要介绍,其次重点讨论了硅纳米球(Si NSs)、硅纳米线(Si NWs)、氧化亚硅纳米线(SiO NWs)、氧化亚硅纳米网(SiO NNs)、高硅含量氧化亚硅纳米线(SiO_(x)NWs)、硅基硅铁合金纳米球(Si/Fe Si_(2)NPs)等几种关键材料的热等离子体法制备及其在锂离子电池负极的应用,最后对热等离子体技术的发展进行了展望。

关键词：射频感应热等离子体锂离子电池硅基负极纳米粉体氧化亚硅

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显微CT技术在钧釉瓷微观结构中的应用

陶瓷学报 2024年第2期45卷 281-289页

作者：王远旭康葆强李合吴军明刘轶群陈伟景德镇陶瓷大学江西景德镇333403 故宫博物院北京100009 北京大学北京100871 河北省文物考古研究院河北石家庄050011

X射线显微镜(显微CT)是一种非破坏性的高分辨率成像技术。采用显微CT扫描和三维重建技术,对金元时期的钧釉瓷内部气泡和孔隙进行三维可视化和定量分析,得到了三维可视化分布图像与定量数据。研究发现,金元时期钧釉瓷釉层气泡尺寸相差大... 详细信息

X射线显微镜(显微CT)是一种非破坏性的高分辨率成像技术。采用显微CT扫描和三维重建技术,对金元时期的钧釉瓷内部气泡和孔隙进行三维可视化和定量分析,得到了三维可视化分布图像与定量数据。研究发现,金元时期钧釉瓷釉层气泡尺寸相差大,且分布离散。其中,大于100μm的气泡主要分布在釉层中层;小于100μm的气泡分布在釉层表层,通过结合岩相分析与化学组成分析发现,该特征的形成与釉的高温黏度、烧成温度等因素有关。研究采用了显微CT扫描与三维重建技术,其是一种无损分析古陶瓷气泡与孔隙特征及工艺的新方法,该研究验证了显微CT在古陶瓷微观结构研究中的可行性和有效性,为古陶瓷制作工艺的科学分析、鉴定、保护和修复等方面提供重要的实验依据。

关键词：显微CT 三维重建无损检测钧釉瓷气泡孔隙

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Observation of Zeeman splitting effect in a laser-driven coil

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Matter and Radiation at Extremes 2022年第2期7卷 18-24页

作者： Baojun Zhu Zhe Zhang Chang Liu Dawei yuan Weiman Jiang Huigang Wei Fang Li Yihang Zhang Bo Han Lei Cheng Shangqing Li Jiayong Zhong Xiaoxia yuan Bowei Tong Wei Sun Zhiheng Fang Chen Wang Zhiyong Xie Neng Hua Rong Wu Zhanfeng Qiao Guiyun Liang baoqiang Zhu Jianqiang Zhu Shinsuke Fujioka Yutong Li Beijing National Laboratory of Condensed Matter Physics Institute of PhysicsCASBeijing 100190China Institute of Laser Engineering Osaka University2-6 Yamada-okaSuitaOsakaJapan Songshan Lake Materials Laboratory DongguanGuangdong 523808China Department of Advanced Photon Research Kansai Photon Science InstituteNational Institutes for Quantum and Radiological Science and Technology619-0215 KyotoJapan Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Department of Astronomy Beijing Normal UniversityBeijing 100875China Center for Advanced Material Diagnostic Technology College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118China Shanghai Institute of Laser Plasma Shanghai 201800China National Laboratory on High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China

The Zeeman splitting effect is observed in a strong magnetic field generated by a laser-driven coil.The expanding plasma from the coil wire surface is concentrated at the coil center and interacts with the simultaneously generated magnetic field.The Cu I spectral lines at wavelengths of 510.5541,515.3235,and 521.8202 nm are detected and analyzed.The splittings of spectral lines are used to estimate the magnetic field strength at the coil center as∼31.4±15.7 T at a laser intensity of∼5.6310^(15) W/cm^(2),which agrees well with measurements using a B-dot probe.Some other plasma parameters of the central plasma disk are also studied.The temperature is evaluated from the Cu I spectral line intensity ratio,while the electron density is estimated from the Stark broadening effect.

关键词： laser splitting effect

垂直上升管内超临界二氧化碳传热恶化机理分析

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化工学报 2023年第8期74卷 3309-3319页

作者：洪瑞袁宝强杜文静山东大学能源与动力工程学院山东济南250061

超临界二氧化碳(SCO_(2))流动传热过程中会发生传热恶化现象,领域内对该现象产生的机理仍存在较大争议。针对现有提出的四类不同的传热恶化机理,通过数值模拟研究,分析在不同工况下内径为5 mm的垂直上升管流动传热过程,从微观层面探究... 详细信息

超临界二氧化碳(SCO_(2))流动传热过程中会发生传热恶化现象,领域内对该现象产生的机理仍存在较大争议。针对现有提出的四类不同的传热恶化机理,通过数值模拟研究,分析在不同工况下内径为5 mm的垂直上升管流动传热过程,从微观层面探究传热恶化机理。研究结果表明,四类机理观点中浮升力效应能更好地解释传热恶化现象,其他三类均具有一定的局限性。SCO_(2)传热恶化现象主要由密度变化引起的浮升力效应导致,当前工况下忽略重力影响时,传热恶化消失。浮升力效应通过改变内部流场的湍流结构,降低了湍动能的产生(层流化),湍流热扩散作用削弱使得传热效率下降,导致了传热恶化现象。研究结果对于SCO_(2)传热恶化的理论研究和预测关联式具有一定的指导意义。

关键词：超临界二氧化碳数值模拟传热恶化浮升力传热

基于XGBoost的三维温盐反演模型声速仿真应用

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海洋科学进展 2023年第3期41卷 520-539页

作者：苑黎明张宝强姜浩刘聪青岛协同创新研究院山东青岛266075 中国人民解放军海军潜艇学院山东青岛266199

基于卫星遥感海面温度和海面高度数据以及Argo数据,利用Extreme Gradient Boosting(XGBoost)算法研究了不同深度三维温盐场的反演模型,实现了30 s内反演2019年1月至12月全球58层温度(盐度)信息,反演的温盐信息与Argo数据的空间和层化分... 详细信息

基于卫星遥感海面温度和海面高度数据以及Argo数据,利用Extreme Gradient Boosting(XGBoost)算法研究了不同深度三维温盐场的反演模型,实现了30 s内反演2019年1月至12月全球58层温度(盐度)信息,反演的温盐信息与Argo数据的空间和层化分布特征吻合,全球58层温度(盐度)反演平均绝对误差和均方根误差分别为0.319℃(0.050)和0.497℃(0.077);南海和西太平洋局部海域的温盐剖面也与Argo数据存在较好的一致性。将XGBoost反演模型得到的温盐信息应用于声速仿真,发现其结果可与Argo数据相吻合。本文的XGBoost温盐反演在保证精度的前提下显著提升了反演效率,能够充分反映海洋内部层化结构,并且可应用于声速仿真研究,为海洋环境信息保障提供技术支撑。

关键词： XGBoost 三维温盐反演声速仿真

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DHX工艺轻烃合格率低问题分析及工艺优化

石油与天然气化工 2022年第4期51卷 58-63页

作者：邹浪李宝强殷珠辉袁标中海石油(中国)有限公司深圳分公司中海油天津化工研究设计院有限公司

目的解决天然气处理能力及轻烃产品质量均未达到设计指标的问题。方法针对某终端投产至今,天然气制冷单元处理量在接近设计值的工况下,存在DHX工艺轻烃产品合格率低、制冷单元系统易回温、操作稳定性差等问题,通过优化设计操作、重新校... 详细信息

目的解决天然气处理能力及轻烃产品质量均未达到设计指标的问题。方法针对某终端投产至今,天然气制冷单元处理量在接近设计值的工况下,存在DHX工艺轻烃产品合格率低、制冷单元系统易回温、操作稳定性差等问题,通过优化设计操作、重新校核选型关键仪器仪表、制定新的工作制度等方式,对制冷单元DHX工艺处理能力及相关工艺参数进行了分析测试。结果单套制冷满负荷连续运行90天,轻烃产品中C_(3)+C_(4)回收率始终大于95%,解决了制冷单元DHX工艺轻烃产品合格率低的问题。结论该方法可为同类型轻烃回收装置提高产品合格率提供经验借鉴。

关键词： DHX 轻烃合格率回温稳定性

高压断路器T100a不同试验程序对比及分析

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高压电器 2023年第12期59卷 223-229页

作者：阎对丰姜子元彭剑飞袁明正张宝强西安高压电器研究院股份有限公司西安710077

在高压断路器的基本短路开断试验中试验方式T100a采用的是非对称电流,由于电流波形与对称电流相比较为复杂,在试验程序上与对称电流开断有较大区别。随着试验技术的不断发展,T100a试验方法也在不断变化,为了厘清T100a的试验程序,文中从... 详细信息

在高压断路器的基本短路开断试验中试验方式T100a采用的是非对称电流,由于电流波形与对称电流相比较为复杂,在试验程序上与对称电流开断有较大区别。随着试验技术的不断发展,T100a试验方法也在不断变化,为了厘清T100a的试验程序,文中从实际工况、试验目的、试验原理、区间划分、试验应力对GB/T4473—2008和GB/T4473—2018中的T100a试验程序进行了分析,指出两者之间的差异和原因,为大容量试验人员和断路器制造商提供技术帮助。

关键词：断路器非对称电流 T100a 试验程序