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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

岩溶水源地安全供水的风险评价指标筛选--以娘子关泉水源地为例

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吉林大学学报（地球科学版） 2018年第3期48卷 805-814页

作者：束龙仓李姝蕾王松克热木.阿布都米吉提鲁程鹏李砚阁李伟河海大学水文水资源学院南京210098 山东省水文局济南250002 南京水利科学研究院南京210029

以山西省阳泉市娘子关泉水源地为例,探索岩溶水源地评价指标体系的建立。在充分考虑娘子关泉水资源特点的基础上,结合DPSIR(驱动力-压力-状态-影响-响应)评价模型和针对岩溶含水层脆弱性的欧洲模式指标框架,建立评价指标备选集。首先选... 详细信息

以山西省阳泉市娘子关泉水源地为例,探索岩溶水源地评价指标体系的建立。在充分考虑娘子关泉水资源特点的基础上,结合DPSIR(驱动力-压力-状态-影响-响应)评价模型和针对岩溶含水层脆弱性的欧洲模式指标框架,建立评价指标备选集。首先选择专家咨询与实际情况相结合的综合分析方法,收集2011—2015年相关指标数据,对所有备选指标进行第一次筛选;然后运用主成分分析法对定量指标进行第二次指标筛选,并用主成分分析法对筛选结果的合理性进行验证;最终确定了涵盖社会、经济、环境、政策4个方面,包含5个准则层19个指标的娘子关泉岩溶水水源地安全供水风险评价指标体系。经过验证,筛选的指标具有合理性和适用性,根据该指标可有效识别水源地风险来源。

关键词：岩溶水源地娘子关泉主成分分析法指标筛选 DPSIR模型

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创新指数指标、测度及应用

科学与管理 2018年第5期38卷 9-16页

作者：李春花逯承鹏董书恒景红双姜璐薛冰青海师范大学地理科学学院青海西宁810007 中国科学院沈阳应用生态研究所辽宁沈阳110016 辽宁省环境计算与可持续发展重点实验室辽宁沈阳110016 中国科学院大学北京100049 兰州大学资源环境学院甘肃兰州730070

随着经济全球化和信息技术的发展,创新能力逐渐成为影响区域经济发展的重要因素并对处于快速发展阶段的中国尤为重要。创新指数是反映、衡量和评价区域创新能力的重要指示器。基于已有研究成果辨析创新指数的概念和内涵,梳理现有创新指... 详细信息

随着经济全球化和信息技术的发展,创新能力逐渐成为影响区域经济发展的重要因素并对处于快速发展阶段的中国尤为重要。创新指数是反映、衡量和评价区域创新能力的重要指示器。基于已有研究成果辨析创新指数的概念和内涵,梳理现有创新指数及主要评价指标和方法。基于CNKI数据库,用Cite Space可视化软件制作以"创新指数"为主题的关键词图谱并进行分析。从国家、区域及企业层面就创新指数从指标体系构建、评价方法、影响因素、创新水平评价等角度对已有研究案例进行系统梳理,指出创新指数未来研究的可能方向和拓展领域。

关键词：创新指数进展指标测度应用

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

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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Limit theorems of the 2D stochastic Navier-Stokes equation driven by a time-periodic force and a degenerate noise

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Science China Mathematics 2025年

作者： Rongchang Liu Kening lu Department of Mathematics University of Arizona School of Mathematics Sichuan University

The periodically forced 2D Navier-Stokes equation with a degenerate noise is studied. For the Markov chain obtained by restricting the solution process to the Poincarésection, we prove a quantitative version of the strong law of large numbers and the central limit theorem with explicit convergence rates. A law of the iterated logarithm is also obtained. The proof is based on a martingale approximation procedure.

关键词：

基于水文要素过程的流域地下水与地表水交换径流成分定量分析

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水资源与水工程学报 2023年第6期34卷 44-51页

作者：王万杰季柯妍刘光牛欣怡陈静刘波束龙仓鲁程鹏河海大学水文水资源学院江苏南京210098 山东省聊城市水文中心山东聊城252000 江西省水文监测中心江西南昌334001

流域地表水-地下水相互作用中包括枯水季节深层地下水向河流稳定补给的基流,降雨入渗后形成的快速与慢速壤中流和洪水时期河道水位抬升引起的地表水补给地下水。目前对于地下水-地表水交换量的组成并没有清晰的定义,已有的水文实验和模... 详细信息

流域地表水-地下水相互作用中包括枯水季节深层地下水向河流稳定补给的基流,降雨入渗后形成的快速与慢速壤中流和洪水时期河道水位抬升引起的地表水补给地下水。目前对于地下水-地表水交换量的组成并没有清晰的定义,已有的水文实验和模拟方法不能准确辨析地下水-地表水交换组分。利用水文要素过程线,提出了综合新安江水文模型、改进马斯京根-康格(Muskingum-Cunge, MC)法和基流分割方法的技术框架,研究地下水-地表水交换量的组成情况,并以婺源江小流域出口断面为例进行了方法应用。研究结果表明:婺源江小流域的地下水-地表水交换量占出口断面总径流的43.54%~54.66%。饱和带中的浅层地下水占出口流量的8.41%~10.57%;降雨下渗进入浅层土壤补给河道的水流占6.81%~20.59%;深层地下水的稳定补给量占河道总径流的23.34%~26.54%。本研究提出了可以精细化辨析地下水-地表水交换分量的技术框架,结果可为类似流域水资源保护与管理提供理论依据。

关键词：地下水与地表水交换径流成分分析水文过程线三水源新安江模型改进马斯京根-康格法基流分割

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宿州市城西水源地地下水限采及其效果分析

水资源保护 2016年第1期32卷 184-189页

作者：孙凤荣温忠辉束龙仓荆艳东鲁程鹏河海大学水文水资源学院江苏南京210098 河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098

针对宿州市城西水源地由于长期开采地下水、井位布局不合理,且地下水补给有限,已严重超采,形成了若干个地下水水位降落漏斗,直接威胁城区供水安全的现实,通过数值模拟法计算宿州市城西水源地的地下水可开采量,采用开采系数法对水源地进... 详细信息

针对宿州市城西水源地由于长期开采地下水、井位布局不合理,且地下水补给有限,已严重超采,形成了若干个地下水水位降落漏斗,直接威胁城区供水安全的现实,通过数值模拟法计算宿州市城西水源地的地下水可开采量,采用开采系数法对水源地进行地下水超采评价,并制定相应的限采方案,预测限采后地下水水位的变化,分析限采效果。结果表明,现状年2010年城西水源地地下水开采系数为1.30,属于严重超采;实施限采方案后,规划年2015年、2020年,地下水开采系数分别为1.21、0.97,限采效果较明显。

关键词：地下水水位地下水超采超采评价限采方案开采系数水源地供水安全