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Design and Application of Turbine Cascade Partitioned Endwall Profiling

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Journal of Thermal Science 2025年第1期34卷 110-128页

作者： ZENG Fei JIANG Ruiqi XUE Xingxu du wei LUO Lei ZHOU Xun AECC Hunan Aviation Powerplant Research Institute Zhuzhou 412002China School of Energy Science and Technology Harbin Institute of TechnologyHarbin 150001China Science and Technology on Diesel Engine Turbocharging Laboratory China North Engine Research InstituteTianjin 300270China

The influence of partitioned profiling design based on a large-pitch highly loaded cascade is studied by numerical *** partitioned profile is mainly composed of a pressure-side convex structure near the leading edge and a suction-side convex structure at the midstream and downstream sides of the *** influence of the change in the vertex axial position and peak value of the B-line on the secondary flow control is *** this paper,air(ideal gas)is selected as the flow *** average static pressure at the outlet and the average total temperature at the inlet are kept *** γ-θ is used as the turbulence *** results show that the pressure-side convex structure suppresses the spanwise and pitchwise migration of the inlet flow by adjusting the static pressure distribution of the flow field,so the development of the pressure-side leg of the horseshoe vortex is effectively *** suction-side convex structure adjusts the static pressure distribution of the flow field and increases the included angle between the cross-flow and suction surface,so the accumulation of low-momentum fluid,the development of a corner vortex and the flow separation at the trailing edge of the suction-side surface are all suppressed near the endwall-suction ***,the energy loss coefficient of the large-pitch highly loaded cascade is decreased from 0.0564 to 0.0485,representing a 25% reduction in secondary flow losses.

关键词： large-pitch highly loaded cascade highly loaded design non-axisymmetrical endwall design secondary flow control partitioned endwall profiling

Phase changes and electromagnetic wave absorption performance of XZnC(X=Fe/Co/Cu)loaded on melamine sponge hollow carbon composites

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International Journal of Minerals,Metallurgy and Materials 2025年第3期32卷 566-577页

作者： Xiubo Xie Ruilin Liu Chen Chen Di Lan Zhelin Chen wei du Guanglei Wu School of Environmental and Material Engineering Yantai UniversityYantai 264005China School of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002China Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta Shandong University of AeronauticsBinzhou 256603China Institute of Materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China

Non-stoichiometric carbides have been proven to be effective electromagnetic wave(EMW)absorbing *** this study,phase and morphology of XZnC(X=Fe/Co/Cu)loaded on a three dimensional(3D)network structure melamine sponge(MS)carbon composites were investigated through vacuum filtration followed by *** FeZnC/CoZnC/CuZnC with carbon nanotubes(CNTs)were uniformly dispersed on the surface of melamine sponge carbon skeleton and Co-containing sample exhibits the highest CNTs *** minimum reflection loss(RL_(min))of the CoZnC/MS composite(m_(composite):m_(paraffin)=1:1,m represents mass)reached-33.60 dB,and the effective absorption bandwidth(EAB)reached 9.60 *** outstanding electromagnetic wave absorption(EMWA)properties of the CoZnC/MS composite can be attributed to its unique hollow structure,which leads to multiple reflections and *** formed conductive network improves dielectric and conductive *** incorporation of Co enhances the magnetic loss capability and optimizes interfacial polarization and dipole *** simultaneously improving dielectric and magnetic losses,ex-cellent impedance matching performance is *** clarification of element replacement in XZnC/MS composites provides an effi-cient design perspective for high-performance non-stoichiometric carbide EMW absorbers.

关键词： electromagnetic wave absorption three dimensional network structure melamine sponge derived carbon non-stoichiometric carbide

Aerodynamic Performance Analysis on Blade Snubber with Bionic Structure

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Journal of Thermal Science 2025年第02期 579-589页

作者： LIU Yunfeng YAN Han du wei ZHANG Hongtao LI Yufeng WEN Fengbo ZHOU Xun School of Energy Science and Engineering Harbin Institute of Technology Harbin Turbine Company Limited

The utilization of a part-span connector(PSC) has the potential to enhance the blade frequency,but with the penalty of aerodynamic *** this study,we numerically investigate the aerodynamic performance of two types of bionic structure snubbers:(1) Harbor seal whisker(HSW) and (2) Atropus' s body shape(ABS).The investigation is conducted by solving the three-dimensional Reynolds-Averaged Navier-Stokes(RANS) equations and utilizing the SST turbulent *** this study,the performance impact of classical snubbers on a cascade blade has been examined by modeling it with and without an ellipse-shaped *** vortex induced by the snubber predominantly manifests on the suction side and can be categorized into three primary vortices:upper,lower,and *** upper and lower vortices serve as the primary contributors to *** to the conventional ellipse snubber,the ABS snubber exhibits a reduction in the total pressure loss coefficient by 0.11% and an increase in the mass flow rate by 0.41%.On the contrary,the implementation of the HSW snubber has the potential to mitigate parameter ***,it is important to note that this comes at the cost of a 0.10% increase in the total pressure loss coefficient and a 0.20% decrease in mass flow *** article further examines the factors contributing to these disparities.

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社会美育论纲

文艺研究 2025年第1期 5-15页

作者：杜卫杭州师范大学艺术教育研究院

社会美育不仅仅是美育实施的一个范围或方面,也是美育的核心问题之一。这一点集中体现于席勒美育思想的社会批判精神和中国现代美育思想的社会改造指向。现代美育思想以对社会现实的批判显示出美学介入社会、重建文化的积极姿态,社会改... 详细信息

社会美育不仅仅是美育实施的一个范围或方面,也是美育的核心问题之一。这一点集中体现于席勒美育思想的社会批判精神和中国现代美育思想的社会改造指向。现代美育思想以对社会现实的批判显示出美学介入社会、重建文化的积极姿态,社会改造和文化重建成为现代社会美育思想的第一要义。社会美育作为美育的核心问题之一,也体现在20世纪初期鲁迅、蔡元培、陈之佛等前辈对中国社会美育的初步构想中,更体现在当今社会美育的公共性上。公共性是当前我国社会美育的基本原则,具体体现为共有、公益和共享。当前,我国社会美育的公共性显示出美育不仅仅发挥着提高大众审美和人文素养的重要作用,而且具有培育大众公共意识、培育公共文化和创新文化的重要功能。

关键词：美育思想社会美育美育实施陈之佛蔡元培公共意识第一要义中国现代美育

Ca2+ cation-mediated microenvironment for electrochemical hydrodimerization of furfural

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Science China Chemistry 2025年

作者： wei du Shuangshuang Cha Can Lei Mengxin Qu Zhongqiang Deng Ming Gong Xinhe Bao Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan University State Key Laboratory of Catalysis National Laboratory for Clean Energy Collaborative Innovation Center of Chemistry for Energy Materials Dalian Institute of Chemical Physics Chinese Academy of Sciences

Furfural is one of the most important biomass-based platform molecules as sustainable precursors for chemicals and fuels. The electrochemical hydrodimerization of furfural can generate hydrofuroin, which is a promising precursor for gasoline or jet ***, steering the selectivity toward hydrodimerization under near-neutral conditions that suppress polymerization and disproportionation of furfural remains challenging. Herein, we discovered that tuning the electrolyte cations could be an effective and alternative strategy for modulating furfural reduction to the traditional electrocatalyst design. Under the optimal Ca2+cations,hydrofuroin yield could be much improved from other cations with hydrofuroin selectivity of 95.5%. The systematic characterization of the ion-centered double layer reflected the suitable sizes and charges of hydrated Ca2+for suppressing the hydrogen evolution reaction from activation of surrounding water molecules as well as encouraging furfural accumulation via non-covalent interaction for directing the electron transfer to furfurals. Ions with smaller or larger sizes can either activate local water molecules or form a crowded ionic interface that casts an adverse effect on furfural enrichment. This work not only presents an effective strategy for facilitating biomass valorization via hydrodimerization but also emphasizes the essential role of the ion-centered microenvironment for steering the electrocatalytic pathways.

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Unintentional emissions of polychlorinated naphthalenes in China:Sources,composition,and historical trends

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Journal of Environmental Sciences 2025年第2期148卷 221-229页

作者： Ye Huang Lin Huang Ying Li Nazupar Sidikjan Yunshan Zhang Yan Chen Yangmin Chen Ye Li wei du Long Chen YanWu Shanshan Zhang Jing Yang Wenjun Meng Guofeng Shen Min Liu Shu Tao Key Laboratory of Geographic Information Science of the Ministry of Education School of Geographic SciencesEast China Normal UniversityShanghai 200241China Yunnan Provincial Key Laboratory of Soil Carbon Sequestration and Pollution Control Faculty of Environmental Science&EngineeringKunming University of Science&TechnologyKunming 650500China Laboratory of Earth Surface Processes College of Urban and Environmental SciencePeking UniversityBeijing 100871China

Polychlorinated naphthalenes(PCNs)are detrimental to human health and the *** the commercial production of PCNs banned,unintentional releases have emerged as a significant environmental ***,relevant information is still *** this study,provincial emissions for eight PCNs homologues from 37 sources in the Chinese mainland during the period of 1960-2019 were estimated based on a source-specific and time-varying emission factor *** results showed that the total PCNs emissions in 2019 reached 757.0 kg with Hebei ranked at the top among all the provinces and iron&steel industry as the biggest ***-chlorinated PCNs comprised 90%of emissions by mass,while highly chlorinated PCNs dominated in terms of toxicity,highlighting divergent priorities for mitigating emissions and safeguarding human *** emissions showed an overall upward trend from 1960 to 2019 driven by emission increase from iron&steel industry in terms of source,and from North China and East China in terms of geographic ***-capita emissions followed an inverted U-shaped environmental Kuznets curvewhile emission intensities decreased with increasing per-capita Gross Domestic Product(GDP)following a nearly linear pattern when log-transformed.

关键词： PCNs Emission inventory Emission factor Composition profile Emission intensity Chinese mainland

Effects of Ti-and Nb-based transition element from single to multiple compound oxides and carbon-based composite additives on Mg-MgH2 hydrogen storage material

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Tungsten 2025年第1期7卷 32-49页

作者： Li-Rong Xiao Chen Chen Shuo Wang Zi-Yin Dai Hideo Kimura Cui Ni Chuan-Xin Hou Xue-Qin Sun Si-Jie Guo wei du Xiu-Bo Xie School of Environmental and Material Engineering Yantai University Bosch HUAYU Steering Systems (Yantai) Co. Ltd.Ytp/MFE University of Tennessee Knoxville Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta Shandong University of Aeronautics

MgH2is considered as a promising hydrogen storage material for its high hydrogen storage capacity,low cost and abundant resource ***,the low kinetics and high enthalpy formation of MgH2limit its wide *** the perspective of adding catalysts to enhance the hydrogen storage properties of Mg-MgH2,this article elaborated the main catalysts based on Ti and Nb transition elements,including single oxide catalysts,binary oxides catalysts（combined with Ni,Na,Sr,V,etc.）,multiple catalysts bound to carbon,and composite catalysts with Ti and Nb elements combined with MXene ***,the main pathways of various catalysts to reduce the reaction activity and broaden the hydrogen desorption channel were also *** Ti-based catalysts can enhance the reactive sites of the matrix by forming multivalent states,while Nb-based catalysts broaden the hydrogen reaction channels by forming tiny *** improving the size structure and enhancing the grain size stability,combined with carbon materials should be the future considerations.

关键词： Catalysts Mg-based hydrogen storage alloys Solid hydrogen storage Transition metal elements

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思维型科学课论证活动的有效支持策略

教学与管理 2025年第5期 40-44页

作者：杜伟广东省深圳市宝安区教育科学研究院广东深圳518101

在小学科学课教学中,一线教师因长期轻视论证活动的价值,或缺乏适切策略支持和引导学生的论证活动,使论证活动变成验证活动,极大地制约了学生科学思维的发展。思维型科学课论证活动的开展可以从课堂论证环境的营造和渲染,核心论点的提... 详细信息

在小学科学课教学中,一线教师因长期轻视论证活动的价值,或缺乏适切策略支持和引导学生的论证活动,使论证活动变成验证活动,极大地制约了学生科学思维的发展。思维型科学课论证活动的开展可以从课堂论证环境的营造和渲染,核心论点的提炼和析出,论证方法的训练和引导,论证依据的铺垫和挖掘等方面着手,帮助学生基于证据与逻辑建立证据与解释之间的关系,并提出合理见解。

关键词：思维型科学课论证活动论证环境核心论点论证方法论证依据

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旋转状态下篦齿流动换热特性研究

工程热物理学报 2025年第1期46卷 138-143页

作者：杨少昀罗磊杜巍王松涛哈尔滨工业大学能源科学与工程学院哈尔滨150001

篦齿封严是一种结构简单有效的封严技术,广泛应用于航空发动机中。本文采用数值模拟的方法研究了旋转对直通型篦齿封严结构流动换热的影响。研究的参数为Ta/Re从0变化0.1。所有的结果都是在雷诺数为6000,10000和15000时获得的。结果表明... 详细信息

篦齿封严是一种结构简单有效的封严技术,广泛应用于航空发动机中。本文采用数值模拟的方法研究了旋转对直通型篦齿封严结构流动换热的影响。研究的参数为Ta/Re从0变化0.1。所有的结果都是在雷诺数为6000,10000和15000时获得的。结果表明,在研究的范围内,旋转速度的增加会降低篦齿通道内的涡流损失和节流损失,从而导致泄漏系数增大;随着转速的增加,顶部壁面的换热增强而齿腔内的换热减弱。

关键词：封严篦齿旋转放电系数换热特性