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学业情绪视域下个性化数学作业对学生影响的研究

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兵团教育学院学报 2025年第1期35卷 77-84页

作者：何玉琪芜湖职业技术学院人文旅游学院安徽芜湖241006

数学是一门逻辑性强、难度大的学科,符合学生个性发展的数学作业会对学生学习和心理发展起事半功倍的效果。为探究个性化数学作业对学生学业情绪的影响机制,研究针对蚌埠市Y中学200名学生进行调查得出主要研究结论:(1)学生对个性化数学... 详细信息

数学是一门逻辑性强、难度大的学科,符合学生个性发展的数学作业会对学生学习和心理发展起事半功倍的效果。为探究个性化数学作业对学生学业情绪的影响机制,研究针对蚌埠市Y中学200名学生进行调查得出主要研究结论:(1)学生对个性化数学作业持积极态度,不存在性别差异。(2)学生的作业态度和认识、完成方式、评价与积极学业情绪呈正相关,作业量和难易程度呈负相关。(3)通过回归分析发现,作业类型对学业情绪没有影响。最后基于研究结果从学业情绪视角提出提升个性化数学作业的建议,为助力个性化数学作业提供实践借鉴。

关键词：个性化数学作业学业情绪调查研究

Magnetic and microwave absorbing properties of Ce-Co-based alloy powders driven with lanthanum content

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Journal of Rare Earths 2020年第7期38卷 749-754,I0003页

作者： yu he Shunkang Pan Jingjing yu School of Material Science and Engineering Guilin University of Electronic TechnologyGuilin 541004China

The composites of Ce-Co-based alloys doped with La content were fabricated via a vacuum arc melting *** influences of La addition on microstructure,electromagnetic parameters,magnetic property and microwave absorbing property were measured by the corresponding *** morphology characteristics manifest that all samples display sheet structure,and the average particle size of alloy powders increases with increasing La content The saturation magnetization(MS) decreases with increasing La addition as a *** minimum reflection loss(RL) of La0.4Ce1.6Co17 alloy powder about-42.29 dB can be obtained about-42.29 dB at 7.84 GHz with the matching thickness of 1.8 mm,and the corresponding effective bandwidth can achieve about 2.24 *** addition,the minimum RL frequency moves towards a lower frequency region as the La content *** minimum RL of La0.3Ce1.7Co17alloy powder is less than-20 dB ranging from 1.2 to 2.4 mm in the whole 4-16 *** maximum bandwidth can reach about 4.88 GHz at the given thickness of 1.2 *** general,these all indicate that the La addition is beneficial to improving the microwave absorbing performance in both effective bandwidth and absorption intensity.

关键词： Ce-Co-Based alloys Magnetic property Microwave absorbing property Reflection loss Rare earths

Complete catalytic oxidation of o-xylene over CeO_2 nanocubes

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Journal of Environmental Sciences 2011年第1期23卷 160-165页

作者： Lian he yunbo yu Changbin Zhang Hong he State Key. Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The activities of CeO2 nanocubes calcined at different temperatures were tested for catalytic oxidation of o-xylene. Using CeO2 nanocubes as catalysts, complete catalytic oxidation of o-xylene was achieved below 210℃. The CeO2 nanomaterials were characterized by means of BET, X-ray diffraction （XRD）, transmission electron microscopy （TEM）, and high-resolution transmission electron microscopy （HRTEM）. From the TEM images, all CeO2 nanocubes displayed cubic morphology irrespective of calcination temperature. The HRTEM images revealed that these nanocubes were enclosed by reactive {001} planes, which may contribute to the intrinsically catalytic property of o-xylene oxidation. The higher activity of CeO2 nanocubes calcined at 550℃ than those calcined at above 550℃ was attributed to their smaller crystallite size and larger surface area. The influences of reaction conditions were also studied, which found that a higher reaction temperature was necessary for complete catalytic oxidation of o-xylene at higher weight hourly space velocity （WHSV） and o-xylene concentration.

关键词： CeO2 nanocubes o-xylene catalytic oxidation calcination temperature

Aero-optical effects simulation technique for starlight transmission in boundary layer under high-speed conditions

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Chinese Journal of Aeronautics 2020年第7期33卷 1929-1941页

作者： Bo YANG Zichen FAN he yu School of Astronautics Beihang UniversityBeijing 100083China

Aero-optical effects for starlight transmission in the high-speed flow field will reduce the accuracy of the star sensor on an *** simulations for aero-optical effects usually require plenty of calculations,which cause difficulties when designing a celestial navigation system for a high-speed *** this study,an Aero-Optical Simulator For Starlight Transmission(AOSST)in the boundary layer is *** effectively reduces the computational burden compared to that of the widely used CFD simulation,and it achieves satisfactory *** this simulator,gas ellipsoids satisfying certain design rules are used to simulate coherent density structures in boundary *** rules for the gas ellipsoids are found from published experimental and high-fidelity CFD simulation *** generated wavefront distortion by AOSST is anchored with the scale law for aero-optical distortion in the boundary layer by determining some control parameters,which enables the simulator to output reliable results over a wide range of flight *** numerical examples are provided to verify the performance of *** results demonstrate that AOSST is able to simulate the directional dependence of aero-optical distortions in boundary layers,the variation trend of distorted wavefront shapes with Reynolds number,and the grayscale distribution on the disturbed star map.

关键词： Aero-optical effect Boundary layer Celestial navigation for high-speed aircraft Coherent structure Starlight transmission