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De novo-design of highly exposed Co−N−C single-atom catalyst for oxygen reduction reaction

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燃料化学学报(中英文) 2025年第1期53卷 128-137页

作者： zhou dan ZHU Hongyue ZHAO Yang LIU Yiming Shanxi Key Laboratory of Catalysis and Energy Coupling School of Chemical Engineering and TechnologyTaiyuan University of Science and TechnologyTaiyuan 030024China Dalian National Laboratory for Clean Energy(DNL) Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

The nitrogen-coordinated metal single-atom catalysts(M−N−C SACs)with an ultra-high metal loading synthetized by direct high-temperature pyrolysis have been widely ***,most of metal single atoms in these catalysts were buried in the carbon matrix,resulting in a low metal utilization and inaccessibility for adsorption of reactants during the catalytic ***,we reported a facile synthesis based on the hard-soft acid-base(HSAB)theory to fabricate Co single-atom catalysts with highly exposed metal atoms ligated to the external pyridinic-N sites of a nitrogen-doped carbon *** from the highly accessible Co active sites,the prepared Co−N−C SAC exhibited a superior oxygen reduction reactivity comparable to that of the commercial Pt/C catalyst,showing a high turnover frequency(TOF)of 0.93 e^(−)·s^(-1)·site^(-1)at 0.85 V ***,far exceeding those of some representative SACs with a ultra-high metal *** work provides a rational strategy to design and prepare M−N−C single-atom catalysts featured with high site-accessibility and site-density.

关键词： hard-soft acid-base Co−N−C single-atom catalyst highly accessible active sites oxygen reduction reaction

“三教”协同服务学习型城市建设路径研究——基于《学习型社会建设重点任务》工作框架

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成人教育 2025年第1期45卷 10-18页

作者：周丹北京市朝阳区职工大学北京100013

职业教育、高等教育和继续教育统筹协同是推动高质量教育体系建设的重要内容,是推动学习型社会和学习型大国建设的重要支撑。学习型城市是学习型社会的基石。以《学习社会建设重点任务》为框架,以服务学习型城市建设为目标支点,探讨职... 详细信息

职业教育、高等教育和继续教育统筹协同是推动高质量教育体系建设的重要内容,是推动学习型社会和学习型大国建设的重要支撑。学习型城市是学习型社会的基石。以《学习社会建设重点任务》为框架,以服务学习型城市建设为目标支点,探讨职业教育、高等教育、继续教育协同服务学习型城市建设的逻辑内涵和工作路径,撬动并推进三类型教育的沟通与协同,共同参与到以价值体系、组织体系、资源体系和研究体系为主要维度的学习型城市建设工作中,以期推动“三教”协同创新路径研究,助力学习型城市建设。

关键词：职业教育高等教育继续教育学习型城市建设 “三教”协同

基于无人机影像和分类器集成的土地使用类型自动识别研究

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城市勘测 2025年第1期 33-37页

作者：周丹贵州省有色金属和核工业地质勘查局五总队贵州安顺561000

为提升土地使用类型自动识别性能,研究基于无人机影像和分类器集成的土地使用类型自动识别方法,使土地使用类型识别精确度更高。利用SLA-4800型号无人机采集城市土地区域无人机影像,以土地全区域涵盖以及乡镇集合等准则为基础,构建土地... 详细信息

为提升土地使用类型自动识别性能,研究基于无人机影像和分类器集成的土地使用类型自动识别方法,使土地使用类型识别精确度更高。利用SLA-4800型号无人机采集城市土地区域无人机影像,以土地全区域涵盖以及乡镇集合等准则为基础,构建土地使用类型自动识别标准,对无人机采集的土地无人机影像进行零均值化以及影像增强处理,实现土地无人机影像预处理,通过采用自动编码机与深度空谱特征联合算法,对预处理后的土地无人机影像进行特征提取,构建以SVM分类器、C4.5决策树分类器以及深度学习分类器组成的集成分类器,最终利用投票辨识实现土地使用类型自动识别。实验表明:该方法处理后土地遥感图像更加清晰,可实现土地使用类型自动识别,且具备较高的识别Kappa系数,有效助力城市各行业的土地配置。

关键词：无人机影像分类器集成土地使用类型自动识别零均值化 SVM分类器

基于代谢组学和网络药理学的蜡梅类黄酮组分评价

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生物工程学报 2025年第2期41卷 602-617页

作者：周丹赵彦贝王梓煦李庆卫北京林业大学园林学院林木资源高效生产全国重点实验室北京100083

类黄酮是蜡梅发挥药理活性的关键功效成分。为了探究蜡梅类黄酮的潜在功效成分及发挥药理活性的作用机制,本研究基于超高效液相色谱-串联质谱的广泛靶向代谢组学技术全面鉴定蜡梅的类黄酮组分,结合网络药理学挖掘蜡梅功效类黄酮组分及... 详细信息

类黄酮是蜡梅发挥药理活性的关键功效成分。为了探究蜡梅类黄酮的潜在功效成分及发挥药理活性的作用机制,本研究基于超高效液相色谱-串联质谱的广泛靶向代谢组学技术全面鉴定蜡梅的类黄酮组分,结合网络药理学挖掘蜡梅功效类黄酮组分及其作用机制,利用分子对接进一步验证网络预测结果,最后进行不同品种蜡梅功效类黄酮含量评估。蜡梅广靶代谢分析中共鉴定出387种类黄酮组分,不同品种蜡梅在黄酮类代谢物上存在显著差异。网络药理学分析鉴定出96种中药化学成分,19种功效活性物质,181个对应靶点,2504个疾病靶点,99个交集靶点,33个核心靶点,涉及229个基因功能条目和99条通路(P≤0.05),显示出蜡梅类黄酮成分在抗氧化、抗炎、杀菌、抗病毒等方面的药理活性。拓扑分析筛选出三裂鼠尾草素、西伯利亚落叶松黄酮、异鼠李素、槲皮素、6-羟基木犀草素共5个核心成分与SRC、PIK3R1、AKT1、ESR1、AKR1C3共5个核心靶点。蜡梅功效类黄酮能够稳定地与关键作用靶点结合,表明这些黄酮类化合物在与靶点的相互作用中具有潜在的生物活性。蜡梅类黄酮代谢产物发挥药理活性的作用机制具有多成分、多靶点和多通路的特点,代谢组学和网络药理学的交叉应用可为深入研究蜡梅的药理功效和治疗机制提供理论依据。

关键词：蜡梅类黄酮分子对接代谢组学网络药理学

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滨涌泵站进出水流道CFD分析

水电站机电技术 2025年第1期48卷 120-124页

作者：周巧丹中山市水利水电勘测设计咨询有限公司广东中山528455

滨涌泵站里有北部排灌渠水,外有小榄水道,为了提升小榄镇防洪排涝能力,评估小榄镇滨涌泵站布置是否合理安全,基于中山市小榄镇滨涌泵站位置环境和建设任务,在分析工程总体布置情况的基础上,根据原型泵主要设计参数,采用三维湍流数值模... 详细信息

滨涌泵站里有北部排灌渠水,外有小榄水道,为了提升小榄镇防洪排涝能力,评估小榄镇滨涌泵站布置是否合理安全,基于中山市小榄镇滨涌泵站位置环境和建设任务,在分析工程总体布置情况的基础上,根据原型泵主要设计参数,采用三维湍流数值模拟方法,通过CFD技术建立数学模型,对潜水贯流泵运行的流道流场及出水系统进行了探讨,研究结果显示,滨涌泵站采用堤身式斜向布置,进、出水流道水流较为平顺,流动相对平稳。为复杂水流下的泵站布置与安全评估提供了借鉴。

关键词：泵站进出水流道 CFD

A multi-level approach to highly efficient recognition of Chinese spam short messages

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Frontiers of Computer Science 2018年第1期12卷 135-145页

作者： Weimin WANG dan zhou School of Computer Science & Engineering Jiangsu University of Science and Technology Jiangsu 212003 China School of Computer and Control Engineering University of Chinese Academy of Sciences Beijing 100190 China

The problem of spam short message （SMS） recognition involves many aspects of natural language pro- cessing. A good solution to solving the problem can not only improve the quality of people experiencing the mobile life, but also has a positive role on promoting the analysis of short text occurring in current mobile applications, such as We- bchat and microblog. As spam SMSes have characteristics of sparsity, transformation and real-timedness, we propose three methods at different levels, i.e., recognition based on sym- bolic features, recognition based on text similarity, and recog- nition based on pattern matching. By combining these meth- ods, we obtain a multi-level approach to spam SMS recog- nition. In order to enrich the pattern base to reduce manual labor and time, we propose a quasi-pattern learning method, which utilizes quasi-pattern matching results in the pattern matching process. The method can learn many interesting and new patterns from the SMS corpus. Finally, a comprehensive analysis indicates that our spare SMS recognition approach achieves a precision rate as high as 95.18%, and a recall rate of 95.51%.

关键词： spam short message spam recognition similar-ity computing pattern learning

Tribological behaviors of graphene oxide partly substituted with nano-SiO_(2) as lubricant additives in water for magnesium alloy/steel interfaces

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International Journal of Minerals,Metallurgy and Materials 2022年第7期29卷 1425-1434页

作者： Hongmei Xie Jiahong Dai dan zhou College of Materials Science and Engineering Yangtze Normal UniversityChongqing 408100China Loncin Industry Chongqing 400052China

Although graphene oxide(GO)has emerged as an excellent lubricant additive in water,there remain great challenges in their practical application due to high production *** taking into account the low cost and also its excellent tribological properties,it is likely that nano-SiO_(2)can be used as a lubricant additive to partially replace ***,this paper aims to explore the tribological properties of nano-SiO_(2)incorporated in GO nanofluids for partial GO replacement by investigating the friction coefficient and wear volume of the prepared SiO_(2)/GO hybrid nanofluids for magnesium alloy/steel sliding *** experiments reveal that the SiO_(2)/GO hybrids retain low friction coefficients as compared to individual GO or SiO_(2)at all test conditions in this ***,as for the bearing capacity test,all samples can provide a low wear volume under the loads of 1 and 3 *** the increase of the normal load,there is considerable differences in the anti-wear *** with that of individual GO nanofluids,the wear volume of the GO/SiO_(2)(mass ratio of 0.3:0.2)hybrid nanofluids was reduced by50.5%at 5 N and by 49.2%at 8 ***,the wear volume of the GO/SiO_(2)(mass ratio of 0.3:0.2)hybrid nanofluids was reduced by46.3%under the rigorous conditions,as compared to individual GO *** findings provide new insights into developing carbon nanomaterial-based hybrid nanofluids for magnesium alloy formation.

关键词： magnesium alloy graphene oxide and nano-silicon dioxide water-based lubricant additive tribological characteristics

The Effect of Concave Size on the Aerodynamics of a Maglev Train

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Journal of Bionic Engineering 2022年第3期19卷 709-723页

作者： Shuang Meng dan zhou Changda Tan Key Laboratory of Traffic Safety on Track(Central South University) Ministry of EducationChangsha410075China Joint International Research Laboratory of Key Technology for Rail Traffic Safety Changsha410075China National and Local Joint Engineering Research Center of Safety Technology for Rail Vehicle Changsha410075China

Inspired by shark’s skin in nature,a non-smooth surface could be an ideal model for changing the flow characteristics of fluids on the object *** analyze the effect of a non-smooth surface with concaves on the maglev train aerodynamic performances and to investigate how the concave size affects the aerodynamic forces and flow structure of a maglev train,four 1/10th scaled maglev train models are simulated using an Improved Delayed Detached Eddy Simulation(IDDES)*** numerical strategy used in this study is verified by comparison with the wind tunnel test results,and the comparison shows that the difference was in a reasonable *** results demonstrate that the concaves could effectively reduce the tail car pressure drag,thus reducing the total drag,and that the smaller the concave size was,the better the drag reduction effect would *** change in the lift with the concave size was more significant than that of the drag,and the tail car lift of R1(0.0012H),R2(0.0024H),and R3(0.0036H)train models was 30.1%,43.0%,and 44.5%less than that of the prototype,*** addition,different flow topologies of the wake are *** width and height of the vortex core of the counter-rotating vortices tended to decrease with the concave ***,from the point of view of ensuring the operating safety of a maglev train,a non-smooth surface with small-size concaves is recommended.

关键词： Maglev train Aerodynamic characteristics Concave Numerical simulation

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校本课程体系的建构思路与实施

中小学校长 2025年第1期 60-62页

作者：汪新华周丹华中师大一附中光谷汤逊湖学校

校本课程体系是落实立德树人根本任务的重要载体。华中师大一附中光谷汤逊湖学校以“源教育”理念为统领,以守“三心”(好奇心、好玩心、好胜心)、养“三趣”(美好兴趣、高雅情趣、崇高志趣)、育“三创”(创新意识、创新品质、创新能力... 详细信息

校本课程体系是落实立德树人根本任务的重要载体。华中师大一附中光谷汤逊湖学校以“源教育”理念为统领,以守“三心”(好奇心、好玩心、好胜心)、养“三趣”(美好兴趣、高雅情趣、崇高志趣)、育“三创”(创新意识、创新品质、创新能力)为旨归,构建了多元、立体、融通的课程生态体系,获得了全要素、全方位、全过程提升学生综合素质和创新能力的育人效果。

关键词：源教育校本课程三心三趣三创