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Chinese Journal of Chemistry 2013年第6期31卷 764-772页

作者： Quan Liu Zhongxiang Lu wenfei Ren Kaibo shen Yu Wang Qing Xu College of Chemistry and Materials Engineering Wenzhou University Wenzhou Zhejiang 325035 China

By optimizing the reaction conditions via a careful screening of the bases and solvents, we developed an efficient transition metal-free method for C--O cross-coupling of activated and unactivated heteroaryl chlorides with primary and secondary alcohols and phenols, providing a simple, efficient, and practical method for synthesis of the useful unsymmetrical heteroaryl alkyl and heteroaryl aryl ethers.

关键词： alcohols C--O cross coupling heteroaryl ethers heteroaryl halides phenols transition metal-free

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60Si2Mn钢的动态再结晶动力学模型

金属热处理 2024年第6期49卷 232-238页

作者：曹成龙陈庆安黄素霞申文飞李河宗曹晶晶李子豪河北工程大学机械与装备工程学院河北邯郸056038 河北工程大学、河北省智能工业装备技术重点实验室河北邯郸056038

研究了60Si2Mn弹簧钢在变形温度730~1000℃、应变速率0.01~5 s^(-1)下的动态再结晶(DRX)行为。通过对试验钢单道次热压缩试验的数据处理,得到了流变应力曲线;借助加工硬化率拟合出各热变形条件下的动态回复曲线,建立动态再结晶动力学模... 详细信息

研究了60Si2Mn弹簧钢在变形温度730~1000℃、应变速率0.01~5 s^(-1)下的动态再结晶(DRX)行为。通过对试验钢单道次热压缩试验的数据处理,得到了流变应力曲线;借助加工硬化率拟合出各热变形条件下的动态回复曲线,建立动态再结晶动力学模型,根据模型预测出不同热变形参数下的动态再结晶体积分数。结果表明,弹簧钢的动态再结晶行为对变形温度和应变速率敏感。随着应变速率的降低或变形温度的升高,动态再结晶软化的临界应变降低,DRX的体积分数增加。预测值与试验值吻合良好,验证了动态再结晶动力学模型对弹簧钢的适用性。

关键词： 60Si2Mn弹簧钢热压缩动态再结晶动力学模型

基于OBE理念的“材料成型理论基础”课程教学改革探索

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科教文汇 2024年第4期 85-89页

作者：陈庆安申文飞赵雷杰杨倩王艳辉河北工程大学机械与装备工程学院河北邯郸056038

“材料成型理论基础”是材料成型及控制工程专业的核心课程,是学习后续专业课程的重要基础。该文针对课程教学特点及问题,基于OBE理念进行了综合教学改革。通过模块化教学、融入课程思政、引入工程案例、实施翻转课堂、改进考核方法等... 详细信息

“材料成型理论基础”是材料成型及控制工程专业的核心课程,是学习后续专业课程的重要基础。该文针对课程教学特点及问题,基于OBE理念进行了综合教学改革。通过模块化教学、融入课程思政、引入工程案例、实施翻转课堂、改进考核方法等多种措施,将课堂教学从知识传授转变为能力培养,将教学活动由以教师为中心转变为以学生为中心。实践证明,该教学模式能够激发学生学习的积极性和主动性,能够帮助学生更好地达到课程学习目标,提高学习效果。

关键词： OBE理念教学改革翻转课堂课程思政

Fabrication and luminescence of KGdF_4:Yb^(3+)/Er^(3+) nanoplates and their improving performance for polymer solar cells

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Science Bulletin 2018年第4期63卷 216-218页

作者： Jiqing Jiao Yao Li wenfei shen Shasha Gai Jianguo Tang Yao Wang Linjun Huang Jixian Liu Wei Wang Laurence A.Belfiore College of Materials Science and Engineering National Center of International Joint Research for Hybrid Materials Technology National Base of International Science &Technology Cooperation Qingdao University Department of Chemical and Biological Engineering Colorado State University

Solar energy remains the most abundant renewable energy resource available to us[1].Continuous efforts have been invested to enhance the conversion of light to electricity by the diverse range of applications[2].Espec... 详细信息

关键词：太阳能电池聚合物制造表演变换效率 PSC PCE 光性质

Linkages among leaf nutrient concentration,resorption efficiency, litter decomposition and their stoichiometry to canopy nitrogen addition and understory removal in subtropical plantation

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Ecological Processes 2024年第2期13卷 90-102页

作者： Jawad Ali Shah wenfei Liu Saif Ullah Honglang Duan Fangfang shen Yingchun Liao Guomin Huang Jianping Wu Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology and Institute of Biodiversity School of Ecology and Environmental Science Yunnan University Laboratory of Soil Ecology and Health in Universities of Yunnan Province Yunnan University Jiangxi Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology Nanchang Institute of Technology Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province Institute for Forest Resources and Environment of Guizhou College of ForestryGuizhou University

Background The prevalence of understory removal and anthropogenic nitrogen(N) deposition has significantly altered the ecological processes of forest ecosystems at both regional and global scales. However, it remains a pressing challenge to understand how N deposition and understory removal affect leaf nutrient dynamics, nutrient resorption, litter decomposition, and their linkages for better managing forest ecosystems under nutrient imbalances induced by N enrichment. To address this research gap, a field manipulation experiment was carried out in a subtropical Cunninghamia lanceolata plantation with four treatments including: control(CK), canopy N addition(CN), understory removal(UR), and canopy N addition plus understory removal(CN × UR). Green and senesced leaf N and phosphorus(P) concentrations, N and P resorption efficiencies, litter decomposition, and their correlations were *** The results revealed that the average N concentrations of green early and late leaves in UR were increased by 6.61 and 18.89% compared to CK. UR had the highest whereas CN had the lowest P concentrations in green leaves across the two sampling seasons. Following this, UR, leaf type, season, and their interactions significantly affected leaf N, P, and N:P(P < 0.05). The highest leaf N resorption(32.68%) and P resorption efficiencies(63.96%) were recorded in UR. Litter decomposition was significantly retarded in UR(P < 0.01) relative to CN. The regression analysis demonstrated that leaf nutrient status was significantly interconnected with leaf nutrient resorption efficiencies. In addition, leaf nutrient dynamics were strongly correlated with litter nutrients, indicating that both were *** These findings can deepen our knowledge of biogeochemical cycling and reveal contrasting nutrientacquisition strategies on N and P limitation in response to UR and CN. Considering the P limitation, it is important to note that P was resorbed more efficiently, illustrating a

关键词： Nutrient resorption Nitrogen deposition Litter decomposition Stoichiometry Understory removal Subtropical plantation

低碳Nb-V-Ti微合金钢X70的奥氏体晶粒长大行为

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金属热处理 2019年第4期44卷 1-5页

作者：杨清张立文张驰申文飞李飞大连理工大学材料科学与工程学院辽宁大连116024

利用金相试验法对低碳Nb-V-Ti管线钢X70在1000～1200℃和0～600 s之间的奥氏体晶粒演化行为进行研究,并利用Beck、Hillert、Sellars数学方程建立了该钢种的晶粒长大模型。结果表明,试验过程中,保温温度越高,时间越长,晶粒尺寸越大,在115... 详细信息

利用金相试验法对低碳Nb-V-Ti管线钢X70在1000～1200℃和0～600 s之间的奥氏体晶粒演化行为进行研究,并利用Beck、Hillert、Sellars数学方程建立了该钢种的晶粒长大模型。结果表明,试验过程中,保温温度越高,时间越长,晶粒尺寸越大,在1150℃以上晶粒越粗化。通过对3种晶粒长大方程:Beck模型,Hillert模型以及Sellars模型的对比分析,Sellars模型对X70管线钢晶粒长大预测精度最高。将模型的预测值与试验结果进行比较,符合较好,说明该方程能够较好预测X70钢的晶粒长大行为。

关键词： X70低碳微合金钢奥氏体晶粒长大 Sellars模型

加氢反应器焊后局部热处理过程数值模拟与工艺优化

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金属热处理 2018年第2期43卷 213-217页

作者：申文飞张立文张驰杨阳朱智大连理工大学材料科学与工程学院

利用有限元软件***建立了加氢反应器焊后局部热处理过程的热力耦合有限元模型,并利用软件的二次开发功能把蠕变变形耦合到有限元模型当中。通过以上模型实现了对加氢反应器焊后局部热处理过程的数值模拟。模拟得到了反应器焊缝附近在不... 详细信息

利用有限元软件***建立了加氢反应器焊后局部热处理过程的热力耦合有限元模型,并利用软件的二次开发功能把蠕变变形耦合到有限元模型当中。通过以上模型实现了对加氢反应器焊后局部热处理过程的数值模拟。模拟得到了反应器焊缝附近在不同热处理阶段的温度场、应变场和畸变场。为了减小反应器热处理后的畸变量,本文提出了优化的热处理工艺。与原始工艺相比,新工艺使反应器的畸变量从-2.31 mm减小为-1.86 mm。

关键词：加氢反应器焊后局部热处理蠕变数值模拟工艺优化

38MnVS6非调质钢棒材轧后冷却过程中的组织转变

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金属热处理 2017年第2期42卷 207-210页

作者：张驰张立文顾森东申文飞夏英男大连理工大学材料科学与工程学院辽宁大连116024

以***有限元分析软件为平台,利用其二次开发功能,结合38Mn VS6非调质钢等温转变曲线,建立了38Mn VS6非调质钢棒材轧后冷却过程的有限元模型,实现了38Mn VS6非调质钢棒材轧后冷却过程温度和相变的耦合计算。通过模拟,得到了棒材轧后冷却... 详细信息

以***有限元分析软件为平台,利用其二次开发功能,结合38Mn VS6非调质钢等温转变曲线,建立了38Mn VS6非调质钢棒材轧后冷却过程的有限元模型,实现了38Mn VS6非调质钢棒材轧后冷却过程温度和相变的耦合计算。通过模拟,得到了棒材轧后冷却过程温度和组织的分布和演变情况。计算得到的组织转变情况与实测结果吻合较好,这对优化38Mn VS6非调质钢棒材轧后冷却工艺参数有一定指导意义。

关键词： 38MnVS6非调质钢轧后冷却数值模拟相转变

L形截面环件径轴向轧制过程数值模拟与工艺优化

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锻压技术 2017年第5期42卷 48-51页

作者：顾森东张立文张驰申文飞徐倩虹大连理工大学材料科学与工程学院辽宁大连116023

径轴向轧制成形技术是生产大型高品质L形截面无缝环件的理想加工方法。以Deform有限元软件为平台,对L形截面环件径轴向轧制过程进行了数值模拟,揭示了L形截面环件轧制过程中折叠和凹坑缺陷的形成机理。以此为基础,对初始环件尺寸和轧制... 详细信息

径轴向轧制成形技术是生产大型高品质L形截面无缝环件的理想加工方法。以Deform有限元软件为平台,对L形截面环件径轴向轧制过程进行了数值模拟,揭示了L形截面环件轧制过程中折叠和凹坑缺陷的形成机理。以此为基础,对初始环件尺寸和轧制工艺进行了优化。研究结果表明:初始环件尺寸和轧制速度设计不合理是缺陷出现的主要原因;优化后的初始环件和进给速度能够消除缺陷,使环件的截面形状填充较好。

关键词： L形截面环件径轴向轧制辗环数值模拟折叠凹坑轧制速度

Heat treatment of hot-isostatic-pressed 60NiTi shape memory alloy:Microstructure,phase transformation and mechanical properties

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Journal of Materials Science & Technology 2022年第12期107卷 124-135页

作者： Yinghao Zhou Xiyu Yao wenfei Lu Dandan Liang Xiaodi Liu Ming Yan Jun shen College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060China Department of Materials Science and Engineering Shenzhen Key Laboratory for Additive Manufacturing of High-performance MaterialsSouthern University of Science and TechnologyShenzhen 518055China

60NiTi alloy is considered to be a promising material for specialized bearing and gear applications due to its high hardness,strength,and low ***,fabricating 60NiTi through conventional processing methods is challenging due to the brittleness and poor *** this study,60NiTi with high relative density was successfully fabricated directly from pre-alloyed powder through hot isostatic *** effects of solution and aging treatments on microstructure and mechanical properties were systematically studied by advanced characterization *** hot-isostatic-pressed 60NiTi showed low average hardness and elastic strain due to the formation of a soft Ni_(3)Ti phase and B2 NiTi *** treatment above 1000℃dissolved the Ni_(3)Ti phase and promoted the formation of nanoscale Ni_(4)Ti_(3)precipitates,which significantly improved the hardness,strength,and elastic strain of *** formation of the Ni_(4)Ti_(3) phase can be mainly attributed to the driving forces induced by the chemical supersaturation and mechanical stress ***,the phase transformation mechanisms during heat treatment and compression test were discussed.

关键词： Ni-rich 60NiTi Hot isostatic pressing Heat treatment Phase transformation Mechanical properties