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形成性评价在口腔医学理论教学中的实践与反思

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黑龙江高教研究 2025年第1期43卷 60-65页

作者：郭若兰林思宇林江首都医科大学附属北京同仁医院北京100730

目的:利用形成性评价对学生的教学评价进行改进,对口腔医学理论的教学方法进行修正,以期望提升临床教学的效果。方法:实验对象为某医科大学临床医学专业学生(包括五年制和5+3一体化两种学制),通过是否参与形成性评价教学分为对照组和实... 详细信息

目的:利用形成性评价对学生的教学评价进行改进,对口腔医学理论的教学方法进行修正,以期望提升临床教学的效果。方法:实验对象为某医科大学临床医学专业学生(包括五年制和5+3一体化两种学制),通过是否参与形成性评价教学分为对照组和实验组。对照组采用传统教学模式,主要利用教师课堂授课;实验组利用形成性评价改进教学模式,不断对学生的学习情况进行反馈和改进,最终通过期末考试定量评价对比学生的学习效果。结果:在两种学制中,实验组学生均比同学制对照组学生期末成绩有所提高,且差异具有统计学意义(P<0.05)。结论:通过形成性评价改进教学模式,能促进学生自主学习,提高学生综合学习的能力,提升学习效果。

关键词：形成性评价口腔医学教学方法

基于分子束外延技术可控制备Ga原子团簇的研究

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原子与分子物理学报 2025年第3期42卷 77-84页

作者：马玉麟郭祥丁召贵州大学大数据与信息工程学院贵阳550025 贵州省微纳电子与软件技术重点实验室贵阳550025 半导体功率器件可靠性教育部工程研究中心贵阳550025

本研究基于分子束外延(Molecular Beam Epitaxy,MBE)技术在Si(100)衬底表面成功制备金属Ga原子团簇.通过控制变量法,研究其尺寸形貌与工艺参数之间的关系.第一组对照实验分别在940℃、970℃、1000℃的Ga源温度下制备Ga原子团簇.实验结... 详细信息

本研究基于分子束外延(Molecular Beam Epitaxy,MBE)技术在Si(100)衬底表面成功制备金属Ga原子团簇.通过控制变量法,研究其尺寸形貌与工艺参数之间的关系.第一组对照实验分别在940℃、970℃、1000℃的Ga源温度下制备Ga原子团簇.实验结果表明,Ga源温度的升高导致Ga的蒸发量增加,进而沉积在Si衬底表面的Ga原子增多,Ga原子自组装成团簇,最终表现为Ga原子团簇的高度升高.第二组对照实验分别在3 s、6 s、10 s、40 s、50 s、60 s的沉积时长下制备Ga原子团簇.实验结果表明,沉积时长增加导致团簇的高度逐渐增加,主要由新吸附原子和竞争效应驱动.第三组对照实验分别在0 s、60 s、300 s的退火时长下制备Ga原子团簇.实验结果表明,退火时长的增加导致团簇的高度下降和团簇内的原子重新排列和分布有关.第四组对照实验分别在420℃、500℃的退火温度下制备Ga原子团簇.实验结果表明,升温至500℃退火会促进Ga原子团簇呈现有序排列,是表面原子的热运动和Ga原子团簇与Si(100)的晶格匹配度的共同作用的结果.

关键词： MBE Ga原子团簇 Ga源温度沉积时长退火时长

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基于分子束外延技术可控制备Bi原子团簇的研究

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原子与分子物理学报 2025年第2期42卷 79-84页

本研究基于分子束外延(MBE)技术在Si(111)衬底表面成功制备金属Bi原子团簇.首先,分别在100℃、125℃、150℃、175℃、200℃的生长温度下,制备了大小均一、密度不同的Bi原子团簇.实验结果表明,可以通过改变生长温度来精细控制Bi原子团簇... 详细信息

本研究基于分子束外延(MBE)技术在Si(111)衬底表面成功制备金属Bi原子团簇.首先,分别在100℃、125℃、150℃、175℃、200℃的生长温度下,制备了大小均一、密度不同的Bi原子团簇.实验结果表明,可以通过改变生长温度来精细控制Bi原子团簇的密度,当温度升高100℃,密度从1.05×10^(11)cm^(-2)降低至2.5×10^(7)cm^(-2),实现对团簇密度4个数量级的可控调节,并且发现Bi原子团簇密度对生长温度的依赖性符合经典成核理论.其次,分别在10 s、15 s、20 s的沉积时长下,制备了密度相同、尺寸各异的Bi原子团簇.实验结果表明,可以通过改变沉积时长来精细控制Bi原子团簇的尺寸:当沉积时长增加10 s,高度和直径分别从8.5 nm和65 nm增大到13.7 nm和100 nm,实现对团簇尺寸在10 nm高度、80 nm直径范围的可控调节,并且发现Bi原子团簇尺寸对沉积时长的依赖性符合晶体生长动力学.与分子束外延制备传统的Ⅲ族(Al,Ga,In)原子团簇做对比,这些结果可以为制备Ⅴ族原子团簇提供实验参考和指导,从而促进纳米级含Bi材料的制备.

关键词：分子束外延 Bi原子团簇生长温度沉积时长经典成核理论晶体生长动力学

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Duals of Hardy Spaces of B-valued Martingales for 0

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Acta Mathematica Sinica,English Series 2014年第8期30卷 1365-1380页

作者： lin yu School of Science China Three Gorges University

The dual of B-valued martingale Hardy space Hr^s（p）（B） with small index 0 〈 r ≤ 1, which is associated with the conditional p-variation of B-valued martingale, is characterized. In order to obtain the results, a new type of Campanato spaces for B-valued martingales is introduced and the classical technique of atomic decompositions is improved. Some results obtained here are connected closely with the p-uniform smoothness and q-uniform convexity of the underlying Banach space.

关键词： Dual spaces B-valued martingale Hardy spaces

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演化博弈模型下我国光伏发电市场规模分析

新疆师范大学学报（自然科学版） 2025年第1期44卷 63-71页

作者：王林忻雨安徽财经大学统计与应用数学学院安徽蚌埠233041

针对中国光伏发电市场规模情况,文章通过定义光伏原材料供应商、光伏原材料分销商、政府和光伏发电企业四方参与者的策略选择,利用复制动态方程构建四方演化博弈模型,分析在不同战略选择下每个参与者之间的收益和成本,并对微分方程稳定... 详细信息

针对中国光伏发电市场规模情况,文章通过定义光伏原材料供应商、光伏原材料分销商、政府和光伏发电企业四方参与者的策略选择,利用复制动态方程构建四方演化博弈模型,分析在不同战略选择下每个参与者之间的收益和成本,并对微分方程稳定性原理和光伏市场中参与者策略之间的动态关系进行数据仿真。研究发现:(1)分销商需要筛选优质产品并提高鉴别能力,从而减少与不守规矩的生产商合作的可能性;(2)企业的维权行为对分销商和政府采取的政策具有积极影响;(3)政府在处理产品质量问题时需要采取多种措施进行综合治理。本研究有助于光伏产业参与者和政策制定者更好地了解市场动态,制定有效的政策和战略。

关键词：光伏发电市场演化博弈策略选择可持续发展

The Enhanced Period Map and Equivariant Deformation Quantizations of Nilpotent Orbits

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Acta Mathematica Sinica,English Series 2024年第3期40卷 885-934页

作者： Shi lin yu Department of Mathematics School of Mathematical SciencesXiamen UniversityXiamen 361005P.R.China

In a previous paper,the author and his collaborator studied the problem of lifting Hamil-tonian group actions on symplectic varieties and Lagrangian subvarieties to their graded deformation quantizations and apply the general results to coadjoint orbit method for semisimple Lie *** even quantizations were considered *** this paper,these results are generalized to the case of general quantizations with arbitrary *** key step is to introduce an enhanced version of the(truncated)period map defined by Bezrukavnikov and Kaledin for quantizations of any smooth sym-plectic variety X,with values in the space of Picard Lie algebroid over *** an application,we study quantizations of nilpotent orbits of real semisimple groups satisfying certain codimension condition.

关键词： Coadjoint orbit method deformation quantization Harish-Chandra modules semisimple Liegroups

Influence of coupled characteristics on the internally-staged combustor under low-power operation

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航空动力学报 2017年第1期32卷 42-52页

作者： KANG Yao lin yu-zhen Hunan Aviation Powerplant Research Institute Aero Engine(Group)Corporation of China National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Energy and Power EngineeringBeijing University of Aeronautics and Astronautics

An ultra-low emissions combustor,namely low emission stirred swirl(LESS)combustor was studied,based on a scheme of internally-staged/lean premixed and prevaporized(LPP)*** LESS combustor consists of central pilot stage and outer surrounded coaxially main stage,between which there exists aphysical isolation,namely the step *** existence of step height delayed the pilot and main jets *** and numerical studies were carried out to investigate the influence of the step height on the combustion performance.A single dome rectangular combustor was utilized to conduct the lean lightoff and blowout experiments,and pollutant emission *** experimental results showed that with the increase of step height by 38%,the lean lightoff and blowout fuel air ratio decreased by 57.4% and 37.5%,the NOx emission increased by 35.1%,and the combustion efficiency increased by 1.78%;while the CO,unburned hydrocarbons(UHC)emissions ***,the total pressure loss was kept nearly ***-reacting and reacting flow fields were numerically investigated to analyze the coupled characteristics of pilot and main jets with different step heights.A comparison of flow characteristics,spray structure,and combustion component as well as temperature field with different step heights was *** numerical results showed that the increase of the step height shifted the peak velocity *** enlargement of the primary recirculation zone(PRZ)resulted in the increase of the combustion efficiency and NOx emission,while the CO,UHC emissions decreeased.

关键词：航空动力编辑研究工作

Gradient estimates and coupling property for semilinear SDEs driven by jump processes

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Science China Mathematics 2015年第2期58卷 447-458页

作者： SONG yu lin School of Mathematical Sciences Beijing Normal University

Let L be a L′evy process with characteristic measureν,which has an absolutely continuous lower bound *** Lebesgue measure on *** using Malliavin calculus for jump processes,we investigate Bismut formula,gradient est... 详细信息

关键词： jump processes Bismut formula gradient estimates coupling property

Microstructure and mechanical properties of a hot-extruded Al-based composite reinforced with core–shell-structured Ti/Al3Ti

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International Journal of Minerals,Metallurgy and Materials 2017年第12期24卷 1431-1437页

作者： Li Zhang Bao-lin Wu yu-lin Liu School of Materials Science and Engineering Shenyang Aerospace UniversityShenyang 110136China Liaoning Key Laboratory of Aviation Light Alloy and Processing Technology Shenyang Aerospace UniversityShenyang 110136China

An Al-based composite reinforced with core–shell-structured Ti/Al_3Ti was fabricated through a powder metallurgy route followed by hot extrusion and was found to exhibit promising mechanical properties. The ultimate tensile strength and elongation of the composite sintered at 620°C for 5 h and extruded at a mass ratio of 12.75:1 reached 304 MPa and 14%, respectively, and its compressive deformation reached 60%. The promising mechanical properties are due to the core–shell-structured reinforcement, which is mainly composed of Al_3Ti and Ti and is bonded strongly with the Al matrix, and to the reduced crack sensitivity of Al_3Ti. The refined grains after hot extrusion also contribute to the mechanical properties of this composite. The mechanical properties might be further improved through regulating the relative thickness of Al–Ti intermetallics and Ti metal layers by adjusting the sintering time and the subsequent extrusion process.

关键词： microstructure aluminum-based composites Ti/Al3Ti reinforcements mechanical properties