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Journal of Materials Science & Technology 2022年第28期123卷 234-242页

作者： Yi Yang Yi Zeng Tongxin Jin Xiaohu Zhang huailong teng Shengyao Wang Hao Chen College of Science Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhan 430070China

Oxygen-vacancies(OVs)play significant roles in semiconductor-based photocatalysis,such as elevating light absorption property,photogenerated carries separation efficiency,molecular activation,and photocatalytic ***,heat-treatment of semiconductors in dangerous H_(2)atmosphere is usually indispensable for OVs *** this work,C-doped Bi_(12)O_(17)C_(12)nanosheets were facially heat-treated in H_(2)O vapor(~2.3 vol%)mixed with Ar at 300℃to in-situ introduce OVs by the proposed reactions of C(s)+H_(2)O(g)→CO(g)+H_(2)(g)and H_(2)(g)+O_(Lattice)→H_(2)O(g)+*** formation of OVs,which was confirmed by electron paramagnetic resonance(EPR),can narrow the band gap,and enhance the photogenerated e~-/h~+separation efficiency on Bi_(12)O_(17)C_(12).Moreover,OVs-rich Bi_(12)O_(17)C_(12)nanosheets can facilitate molecular O_(2)activation and produce more reactive oxygen species(ROS),especially~1 O_(2),which greatly improve the NO to NO_(3)~-conversion efficiency with NO removal rate of~63%and NO_(3)~-production selectivity of~92.6%.The present work will bring new insights into the construction and roles of OVs in semiconductor-based photocatalysis.

关键词： Oxygen-vacancies H_(2)O vapor Photocatalytic NO oxidation ~1O_(2)

Copper-catalyzed asymmetric 1,3-dipolar cycloaddition of azomethine ylides withβ-trifluoromethyl-substituted alkenyl heteroarenes

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Science China Chemistry 2023年第11期66卷 3193-3204页

作者： Xiang Cheng Xin Chang Yuhong Yang Zongpeng Zhang Jing Li Yipu Li Wenxiao Zhao Lung Wa Chung huailong teng Xiu-Qin Dong Chun-Jiang Wang College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryShanghai 230021China Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055China College of Science Huazhong Agricultural UniversityWuhan 430070China

Copper-catalyzed asymmetric 1,3-dipolar cycloaddition of azomethine ylides andβ-trifluoromethyl-substituted alkenyl heteroarenes was developed for the first time.A wide range of enantioenriched pyrrolidines containing both heteroarenes and trifluoromethyl group with multiple stereogenic centers could be readily accessible by this method with good to high yields and excellent levels of both stereo-and regioselectivity(up to 99%yield,>20:1 rr,>20:1 dr,and up to 95%ee).Notably,substratecontrolled umpolung-type dipolar cycloaddition was also disclosed in this protocol to achieve regiodivergent synthesis withα-aryl substituted aldimine esters as the dipole *** DFT studies were conducted to explore the origin of the stereo-and regioselectivity of this 1,3-dipolar cycloaddition,and suggest that copper(Ⅱ)salt utilized in this catalytic system could be reduced in-situ to the active copper(Ⅰ)species and might be responsible for the observed high stereo-and regioselectivity.

关键词： asymmetric catalysis 1 3-dipolar cycloaddition chiral pyrrolidines heteroarene trifluoromethyl group

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Designed polymeric conjugation motivates tunable activation of molecular oxygen in heterogeneous organic photosynthesis

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Science Bulletin 2022年第1期67卷 61-70,M0004页

作者： Wenhao Sun Yonggang Xiang Zhihui Jiang Shengyao Wang Nan Yang Shangbin Jin Linhao Sun huailong teng Hao Chen College of Science Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Environment Correlative Dietology(Ministry of Education) Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Material Chemistry for Energy Conversion and Storage(Ministry of Education) School of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Photocatalytic oxidative organic reactions are important synthetic transformations,and research on reaction selectivity by reactive oxygen species(ROS)is *** date,however,there has rarely been any focus on the directed generation of ***,we report the first identification of tunable molecular oxygen activation induced by polymeric conjugation in nonmetallic conjugated microporous polymers(CMP).The conjugation between these can be achieved by the introduction of alkynyl ***-A with an alkynyl bridge facilitates the intramolecular charge mobility while CMP-D,lacking an alkynyl group enhances the photoexcited carrier build-up on the surface from *** different processes dominate the directed ROS generation of the superoxide radical(·O_(2)^(-))and singlet oxygen(^(1)O_(2)),*** theory is substantiated by the different performances of these CMPs in the aerobic oxidation of sulfides and the dehydrogenative coupling of amines,and could provide insight into the rational design of CMPs for various heterogeneous organic photosynthesis.

关键词： Photocatalysis Conjugated polymers Molecular oxygen activation Aerobic oxidation Polymeric conjugation

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基于BIM的集成化建设范式理论研究

山西建筑 2015年第27期41卷 234-235页

作者：滕怀龙张洋国家开发银行青岛市分行山东青岛266071

对建筑信息模型(BIM)进行了简单介绍,分析了基于BIM的集成化建设范式的形式背景和形成依据,着重对基于BIM的工程项目集成化建设范式的特征进行了描述,指出基于BIM的集成化建设模式是未来主流的建设生产模式。

关键词： BIM 集成化范式信息

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高寒动车组-40℃环境下动力学性能

机械工程学报 2019年第4期55卷 148-153页

作者：滕万秀罗仁石怀龙曾京西南交通大学牵引动力国家重点实验室成都610031 中车长春轨道客车股份有限公司高速列车系统集成国家工程实验室长春130062

低温环境对高速动车组动力学性能影响显著,需要掌握低温下的车辆参数变化范围,针对-40℃或极低温工况鲜有研究。基于悬挂元件低温特性试验结果,建立高寒动车组非线性动力学仿真模型,并将常温环境下的动力学仿真结果与线路试验结果进行... 详细信息

低温环境对高速动车组动力学性能影响显著,需要掌握低温下的车辆参数变化范围,针对-40℃或极低温工况鲜有研究。基于悬挂元件低温特性试验结果,建立高寒动车组非线性动力学仿真模型,并将常温环境下的动力学仿真结果与线路试验结果进行对比验证;将车辆系统悬挂参数、轮轨匹配、轮轨界面参数考虑为正态随机分布,采用拉丁超立方采样方法组合得到300种计算工况,仿真研究高寒动车组在-40℃低温环境运行时的动力学性能。300 km/h速度条件下,车辆运行稳定性和安全性能满足标准要求,但新镟修车轮在直线运行工况下的横向平稳性较常温环境下差,主要是由于车辆发生了横向低频晃动;低温引起橡胶元件和减振器的刚度和阻尼增大,导致在与车体上心滚摆接近的频率范围内,前后转向架同向蛇行运动的阻尼比降低,引发以车体滚摆为主的横向晃动,因此高寒动车组需要注意预防新镟轮后的车体晃动现象。为低温环境下的高速动车组悬挂参数使用范围和动力学性能设计提供了参考。

关键词：动车组动力学仿真线路试验随机因素极低温环境