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Numerical Study of Flow and Heat Transfer Characteristics of Shell-and-Tube Molten Salt Electric Heater with Circularly Perforated Baffles

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Journal of Thermal Science 2025年第1期34卷 24-33页

作者： LIN Yongjie ZHANG Cancan WU Yuting ZHANG Yi lu Yuanwei Key Laboratory of Heat Transfer and Energy Conversion National User-Side Energy Storage Innovation Research and Development CenterBeijing University of Technology

Numerical simulations of the flow and heat transfer characteristics of four shell-and-tube molten salt electric heaters with different perforation rates was ***-and-tube electric heaters have the same geometry and tube arrangement,and all of them use single segmental baffles,but there exist four different baffle openings（φ）,i.e.,0%,2.52%,4.06%,and 6.31%.The results indicated that the reasonable baffle opening could significantly reduce the shell-side pressure drop,effectively decreasing the shell-side flow dead zone *** can eliminate the local high-temperature phenomenon on the surface of electric heating tubes,but the heat transfer coefficient is slightly *** perforated schemes significantly reduce shell-side pressure drop compared to the baseline solution without open *** particular,the φ=6.31% scheme exhibits the optimal performance among all the schemes,with a maximum reduction of up to 50.50% in shell-side pressure drop relative to the unopened holes *** heat transfer coefficient is the highest for φ=0%,exhibiting a range of5.26% to 5.73%,5.14% to 5.99%,and 7.31% to 8.54% higher than φ=2.52%,4.06%,and 6.31%,respectively,within the calculated *** composite index h/（Δp）1/3was higher for all open-hole solutions than that for the unopened-hole *** best overall performance was for φ=6.31%,which improved the composite index by15.29% to 17.18% over the unopened-hole solution.

关键词： molten salt electric heater perforated baffles heat transfer

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鼻腔鼻窦浆细胞肉芽肿诊治探讨

中华耳鼻咽喉头颈外科杂志 2018年第5期53卷 385-386页

作者：路亚茹李世超王卫卫尹志华王广科河南省人民医院耳鼻咽喉科郑州450003

浆细胞肉芽肿（plasma cell granuloma，PCG）是一种病因不明、临床表现无特异性的炎性占位性病变。由于该病发病率较低，目前对该病的认识及诊疗方案仍有待进一步提高。本文对我院5例鼻腔鼻窦PCG病例进行回顾性分析，并探讨其临床表现... 详细信息

浆细胞肉芽肿（plasma cell granuloma，PCG）是一种病因不明、临床表现无特异性的炎性占位性病变。由于该病发病率较低，目前对该病的认识及诊疗方案仍有待进一步提高。本文对我院5例鼻腔鼻窦PCG病例进行回顾性分析，并探讨其临床表现、临床诊治方法，以期提高对该病的诊疗水平。

关键词：浆细胞肉芽肿鼻腔鼻窦临床诊治临床表现占位性病变 cell 病因不明特异性

青少年型重症肌无力的临床特征和相关基因变异情况分析

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中华医学杂志 2022年第19期102卷 1445-1449页

作者：杨文昊鲁亚茹邱力欧昶毅林中强黄志东刘卫彬中山大学附属第一医院神经科广东省重大神经疾病诊治研究重点实验室国家临床重点专科和国家重点学科广州510080

目的分析青少年型重症肌无力(MG)患者的临床特征及相关基因变异特点。方法收集2019年6月至2020年5月在中山大学附属第一医院神经内科就诊的青少年型MG患者的临床资料, 征得患者知情同意后留取血标本, 应用Illumina平台对血标本进行全外... 详细信息

目的分析青少年型重症肌无力(MG)患者的临床特征及相关基因变异特点。方法收集2019年6月至2020年5月在中山大学附属第一医院神经内科就诊的青少年型MG患者的临床资料, 征得患者知情同意后留取血标本, 应用Illumina平台对血标本进行全外显子检测, 运用生物信息软件及SPSS 22.0进行数据处理及结果分析。结果根据纳入和排除标准共纳入54例青少年型MG患者, 男28例, 女26例, 起病年龄(3.79±0.89)岁。入组患者中眼肌型患者52例(96.3%), 54例患者的MG-ADL评分为(3.44±0.44)分, AChR-Ab抗体滴度为(5.88±2.45)nmol/L。2例患者合并胸腺增生, 5例患者有MG家族史。在54例患者中共发现了169个变异基因, 其中肌联蛋白titin(TTN)基因变异例数最多, 共发生变异17例(31.5%)。TTN基因变异组中, 有7例(7/17)患者有眼球固定表现, 非变异组中有4例(10.8%)患者出现眼球固定症状, 两组比较差异有统计学意义(P=0.016)。突触核包膜蛋白1(SYNE1)和兰尼碱受体1(RYR1)基因变异共7例(13.2%), 未发现此类基因变异与MG临床表现的明确关系。结论青少年型MG的好发人群为学龄前儿童, 无性别差异, 以眼肌型多见。青少年型MG中TTN基因变异比例较高, 提示该基因可能是青少年型MG患者的潜在治疗靶点。

关键词：重症肌无力青少年全外显子测序横断面研究

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生理性起搏的临床应用

天津医药 2000年第4期28卷 209-211页

作者：田青平路雅茹吴建国天津市胸科医院心内科 300051

目的:探讨生理性起搏的临床应用。方法:37例病态窦房结综合征(SSS)患者安置AAI型起搏器;46例心律失常患者和15例肥厚型梗阻性心肌病(HOCM)患者安置DDD型起搏器。所有患者均进行随访,并对HOCM患者进行血液动力学观察。结果:经3个月至6年... 详细信息

目的:探讨生理性起搏的临床应用。方法:37例病态窦房结综合征(SSS)患者安置AAI型起搏器;46例心律失常患者和15例肥厚型梗阻性心肌病(HOCM)患者安置DDD型起搏器。所有患者均进行随访,并对HOCM患者进行血液动力学观察。结果:经3个月至6年随访,所有心律失常患者临床症状均显著改善,37例AAI起搏患者无1例发生房室传导阻滞;15例HOCM患者左室流出道增宽,压力阶差减低,使流出道梗阻得到不同程度的缓解。结论:AAI及DDD起搏可提供房室顺序起搏。对药物治疗无效的HOCM患者DDD起搏为一种能替代外科手术、安全有效的治疗方法;对病态窦房结综合征患者AAI起搏器为实用、经济、简单的生理性起搏。

关键词：生理性起搏临床应用人工心脏起搏器

Infrared small target detection based on spatial attention density peaks searching

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Optoelectronics Letters 2025年第2期21卷 90-96页

作者： RAO Junmin lu Siyu LIU Shijian LI Fanming CAS Key Laboratory of Infrared System Detection and Imaging Technology Shanghai Institute of Technical Physics University of Chinese Academy of Sciences Shanghai Institute of Technical Physics Chinese Academy of Sciences School of Information Science and Technology Shanghai Tech University

The detection of small targets poses a significant challenge for infrared search and tracking (IRST) systems,as they must strike a delicate balance between accuracy and *** this paper,we propose a detection algorithm based on spatial attention density peaks searching (SADPS) and an adaptive window selection ***,the difference-of-Gaussians (DoG) filter is introduced for preprocessing raw infrared ***,the image is processed by ***,an adaptive window selection scheme is applied to obtain window templates for the target scale ***,the small target feature is used to enhance the target and suppress the ***,the true targets are segmented through a *** experimental results show that compared with the seven state-of-the-art small targets detection baseline algorithms,the proposed method not only has better detection accuracy,but also has reasonable time consumption.

关键词： Infrared imaging

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我国近20年土地利用变化研究状态

西部大开发（土地开发工程研究） 2020年第4期5卷 54-58页

作者：卢雅茹陈南南闫瑾长安大学地球科学与资源学院陕西西安710054 长安大学土地工程学院陕西西安710054 陕西省土地整治重点实验室陕西西安710054

以cnki中1997~2019年与土地利用变化相关的文献为研究样本,运用CiteSpace作为文献可视化工具,对文献数据集的历年发文量、核心作者、科研单位、关键词及研究热点进行分析。结果表明:研究文献呈阶段性增长特征,经历了从快速增长到稳定增... 详细信息

以cnki中1997~2019年与土地利用变化相关的文献为研究样本,运用CiteSpace作为文献可视化工具,对文献数据集的历年发文量、核心作者、科研单位、关键词及研究热点进行分析。结果表明:研究文献呈阶段性增长特征,经历了从快速增长到稳定增长的发展过程,文献数量总体呈现持续增长状态;研究土地利用变化的科研团队数量较多,但研究机构间的跨机构、跨地区、跨学科的合作较少,研究人员普遍呈分散化特征,学者间的联系并不紧密;土地利用变化研究的科研机构主要集中在高等科研院校;研究方向呈清晰化特征,当前我国关于在土地利用变化主要研究遥感、地理信息系统、构建模型、驱动力、气候变化等指标;主要研究区域是黄土高原黄土丘陵沟壑区以及农牧交错带等。

关键词：土地利用变化模型驱动力可视化

An embedded electron current layer observed at the edge of the plasma sheet in the Earth’s magnetotail

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Earth and Planetary Physics 2025年第1期9卷 148-158页

作者： ChenChen Zhan RongSheng Wang QuanMing lu San lu XinMin Li Deep Space Exploration Laboratory/School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences(CAS)Center for Excellence in Comparative Planetology/CAS Key Laboratory of Geospace Environment/Anhui Mengcheng National Geophysical Observatory University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China

The formation of an embedded electron current sheet within the magnetotail plasma sheet has been poorly *** this article,we present an electron current layer detected at the edge of the magnetotail plasma *** ions were demagnetized inside the electron current layer,but the electrons were still frozen in with the magnetic field ***,this decoupling of ions and electrons gave rise to a strong Hall electric field,which could be the reason for the formation of the embedded thin current *** magnetized electrons,the absence of the nongyrotropic electron distribution,and negligible energy dissipation in the layer indicate that magnetic reconnection had not been triggered within the embedded thin current *** highly asymmetric plasma on the two sides of the current layer and low magnetic shear across it could suppress magnetic *** observations indicate that the embedded electric current layer,probably generated by the Hall electric field,even down to electron scale,is not a sufficient condition for magnetic reconnection.

关键词： magnetotail plasma sheet magnetic reconnection

Spatio-temporal patterns and climatic drivers of spring phenology in eight forest communities across the north-south transitional zone of China

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Journal of Geographical Sciences 2025年第1期35卷 17-38页

作者： ZHU Wenbin lu Yu Institute of Geographic Sciences and Natural Resources Research CAS School of Geographical Science Nanjing University of Information Science & Technology

The Qinba Mountains are climatically and ecologically recognized as the northsouth transitional zone of *** of its phenology is critical for comprehending the response of vegetation to climatic *** retrieved the start of spring phenology （SOS）of eight forest communities from the MODIS products and adopted it as an indicator for spring *** analysis,partial correlation analysis,and Geo Detector were employed to reveal the spatio-temporal patterns and climatic drivers of *** results indicated that the SOS presented an advance trend from 2001 to 2020,with a mean rate of–0.473 d yr–*** SOS of most forests correlated negatively with air temperature （TEMP） and positively with precipitation （PRE）,suggesting that rising TEMP and increasing PRE in spring would forward and delay SOS,*** dominant factors influencing the sensitivity of SOS to climatic variables were altitude,forest type,and latitude,while the effects of slope and aspect were relatively *** response of SOS to climatic factors varied significantly in space and among forest communities,partly due to the influence of altitude,slope,and aspect.

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Electrocatalytic selective synthesis and tandem utilization of hydroxylamine

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Science China Chemistry 2025年

作者： Yuxuan lu Hengquan Yang Engineering Research Center of Ministry of Education for Fine Chemicals School of Chemistry and Chemical Engineering Shanxi Key Laboratory of Green Catalytic Synthesis of Coal-based High Value Chemicals Shanxi University

The transformation of renewable nitrogen feedstock to nitrogenous chemicals plays a significant role in our modern society,considering the crucial impact of nitrogenous chemicals on life sciences,biomedicine,agriculture,and *** （NH2OH）,a typical nucleophile,has been widely served as the nitrogenous feedstock to produce nitrogenous *** NH2OH synthesis methods rely on harsh reaction conditions,leading to an unfavorable environmental *** contrast,nitric oxide electroreduction promises to produce NH2OH powered by renewable *** achievements have revealed the possibility of this process,but have also identified significant *** activity and selectivity are fundamentally limited by competing hydrogenation reactions,while the performance evaluation with high accuracy and reproducibility is ***,this review aims to provide insight into the mechanism of NH2OH electrosynthesis,especially regarding understanding reaction pathways and the design principle towards efficient ***,the performance evaluation parameters and standard measurement methods for NH2OH synthesis are summarized to screen efficient ***,the prospects and emerging opportunities to synthesize nitrogen-containing organic compounds by tandem reaction are *** review aims to provide a guide for evaluating and exploring efficient electrocatalytic systems for NH2OH production and utilization technology.

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