检索结果-南通市图书馆

甲醇直接气相氧化羰基化合成碳酸二甲酯铜基催化剂的研究进展

在线全文

学校读者我要写书评

暂无评论

工业催化 2012年第4期20卷 1-6页

作者：郭天玉郑华艳董睿敏孟凡会李忠太原理工大学煤科学与技术教育部和山西省重点实验室山西太原030024

综述了近年来甲醇直接气相氧化羰基化合成碳酸二甲酯的铜基催化剂由含氯催化剂、低氯催化剂到完全无氯催化剂的研究进展,总结了各类催化剂的结构特征、催化性能及存在问题,并指出催化剂的发展趋势和应用前景。

关键词：催化化学甲醇铜基催化剂气相氧化羰基化碳酸二甲酯

De novo synthesis of atropisomeric benzofurans via Cu/SPDO complex catalyzed asymmetric formal [3 + 2] annulation

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第1期68卷 174-180页

作者： Fan-Xiao meng Xing-Yu Wang Ka Lu Ju-Song Yang Fu-Min Zhang Ai-Jun Ma Bao Du Yong-Qiang Tu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University School of Biotechnology and Health Sciences Wuyi University

Herein, the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO) complex catalyze asymmetric formal [3 + 2] cycloaddition between quinones and ynamides is explored, producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities. Furthermore, density functional theory calculations were applied to explain the possible reaction mechanism.

关键词： benzofuran atropisomers novel de novo synthetic strategy asymmetric formal [3 + 2] cycladdition Cu/SPDO complex DFT calculations

系列化中国标准地铁用踏面制动单元壳体结构设计与试验研究

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

机械设计与制造工程 2023年第6期52卷 58-62页

作者：张宇宸程中国孟繁辉冯畅胡瑞霞中车戚墅堰机车车辆研究所有限公司江苏常州213011 青岛地铁集团有限公司山东青岛266045 中车长春轨道客车股份有限公司吉林长春130011

提出系列化中国标准地铁用踏面制动单元壳体的新型正向设计方法。首先对产品内部机构进行运动学分析,计算出内部机构包络空间。然后根据转向架安装需求,设计出壳体的外形,并进行工程化处理。随后对所设计的壳体进行静强度有限元仿真计... 详细信息

提出系列化中国标准地铁用踏面制动单元壳体的新型正向设计方法。首先对产品内部机构进行运动学分析,计算出内部机构包络空间。然后根据转向架安装需求,设计出壳体的外形,并进行工程化处理。随后对所设计的壳体进行静强度有限元仿真计算以及模态仿真分析。最后试制出壳体实物并进行试验,应力应变试验结果表明,壳体主要部位的实际应力值与静强度仿真计算结果基本一致,壳体实物满足极限工况下的承载要求;动作疲劳试验的结果符合相关标准要求。上述计算与试验结果表明,采用该方法所研制的壳体在外形、质量、强度等方面均能满足标准地铁车辆要求。

关键词：踏面制动单元运动包络强度校核模态分析应力测试

维普期刊数据库博看期刊

在线全文

学校读者我要写书评

暂无评论

山东一次春季冷空气10级大风的天气成因

海洋气象学报 2024年第1期44卷 52-64页

作者：刘畅胡宁李昱薇朱晓清孟凡辉卢绪兰山东省气象防灾减灾重点实验室山东济南250031 山东省气象台山东济南250031 国家气象中心北京100081 德州市气象局山东德州253053 山东省气象科学研究所山东济南250031 长岛国家气候观象台山东长岛265800

2020年3月18日中午至夜间,山西、河北、北京、天津和山东等地先后出现阵风10级及以上强风天气。利用风廓线雷达、国家级地面气象观测站和欧洲中期天气预报中心(European Centre for Medium-Range Weather Forecasts, ECMWF)第五代大气... 详细信息

2020年3月18日中午至夜间,山西、河北、北京、天津和山东等地先后出现阵风10级及以上强风天气。利用风廓线雷达、国家级地面气象观测站和欧洲中期天气预报中心(European Centre for Medium-Range Weather Forecasts, ECMWF)第五代大气再分析数据(ECMWF Reanalysis v5,ERA5)等资料,对强风过程的天气学成因进行了分析。结果表明:强风发生在低空暖脊异常发展的热力环境条件下,冷锋自黄土高原下到华北平原,中层锋消,垂直方向上发生“断裂”,低层冷锋先行侵入热低压,在锋生过程中发生。强风具有显著的非地转瞬变特征,低层强冷平流是强变压梯度产生的主要因素,变压风叠加在快速移动的冷锋系统中诱发大风,变压风是重要组成部分;低空动量下传效应引起低层风速波动,但不足以直接诱发强风。

关键词：春季冷空气 10级大风锋生变压风动量下传地转适应

维普期刊数据库博看期刊

Low‑Temperature Fabrication of Stable Black‑Phase CsPbI_(3)Perovskite Flexible Photodetectors Toward Wearable Health Monitoring

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2025年第3期17卷 232-245页

作者： Yingjie Zhao Yicheng Sun Chaoxin Pei Xing Yin Xinyi Li Yi Hao mengru Zhang meng Yuan Jinglin Zhou Yu Chen Yanlin Song College of Chemistry and Pingyuan Laboratory Zhengzhou UniversityZhengzhou 450001People’s Republic of China Key Laboratory of Green Printing Institute of ChemistryChinese Academy of SciencesBeijing 100190People’s Republic of China Key Laboratory of Bio‑Inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190People’s Republic of China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049People’s Republic of China

Flexible wearable optoelectronic devices fabricated fromorganic–inorganic hybrid perovskites significantly accelerate the developmentof portable energy,biomedicine,and sensing fields,but their poor thermal stabilityhinders further ***,all-inorganic perovskites possessexcellent thermal stability,but black-phase all-inorganic perovskite filmusually requires high-temperature annealing steps,which increases energy consumptionand is not conducive to the fabrication of flexible wearable *** this work,an unprecedented low-temperature fabrication of stable blackphaseCsPbI3perovskite films is demonstrated by the in situ hydrolysis reactionof diphenylphosphinic chloride *** released diphenyl phosphateand chloride ions during the hydrolysis reaction significantly lower the phasetransition temperature and effectively passivate the defects in the perovskitefilms,yielding high-performance photodetectors with a responsivity of 42.1 AW−1 and a detectivity of 1.3×10^(14)***,high-fidelity imageand photoplethysmography sensors are demonstrated based on the fabricated flexible wearable *** work provides a newperspective for the low-temperature fabrication of large-area all-inorganic perovskite flexible optoelectronic devices.

关键词： In situ hydrolyzation Low-temperature processing All-inorganic perovskite Flexible photodetectors Health monitoring

Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing Chen Chao Wu Xiaoling Liu Biao meng Tao Chen Yu Han Jun Wang Shibo Xi Yu Zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Activation energy

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

标准地铁列车供风制动系统平台搭建和简统

智慧轨道交通 2022年第6期59卷 16-21页

作者：孟繁辉高靖添王雯任得鹏项宇航汝泽洋中车长春轨道客车股份有限公司吉林长春130062 中车株洲电力机车有限公司湖南株洲412001 中车大连机车车辆有限公司辽宁大连116021

基于系列化中国标准地铁列车的研制,按照整车顶层设计要求,以用户需求为导向,基于安全可靠的原则,在考虑产品多样化的前提下开展供风制动系统平台搭建和简统。通过对国内速度80~120 km/h各型地铁车辆运用环境和需求的分析,确定系统的顶... 详细信息

基于系列化中国标准地铁列车的研制,按照整车顶层设计要求,以用户需求为导向,基于安全可靠的原则,在考虑产品多样化的前提下开展供风制动系统平台搭建和简统。通过对国内速度80~120 km/h各型地铁车辆运用环境和需求的分析,确定系统的顶层技术参数和平台架构。搭建的系统平台采用统一的系统原理、系统功能和接口,可根据市场项目需求选择配置所需要的功能模块;对系统关键部件和备品备件实施深度简统,经市场批量推广后将会显著降低研制和维修成本、缩短研制的时间,同时也给系统安全和可靠性的提高提供了保障。

关键词：标准地铁制动系统供风平台搭建简统

综合性医院临床微生物实验室建设中须注意的问题

在线全文

学校读者我要写书评

暂无评论

中国医院建筑与装备 2016年第12期17卷 76-79页

作者：孟凡辉刘波常玉霞刘英伟曹红云王丽淄博市临淄区人民医院淄博255400

文章以淄博市临淄区人民医院临床微生物和感染实验室工程为例,阐述了二级生物安全实验室在建设过程中存在的问题,并从规划设计、结构与装修、空调净化等多个方面详细介绍了应对这些问题的具体措施和方法。

关键词：临床微生物实验室感染实验室生物安全实验室实验室设计

Small modifications of endo-functionalized cavities lead to large changes in molecular interaction in water

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第1期68卷 369-376页

作者： Song-meng Wang Hao Nian Yan-Fang Wang Li-Shuo Zheng Yu-Tao Zheng Yi-Wei Dong Liping Huang Xiaoping Wang Wei Jiang Liu-Pan Yang Department of Chemistry Southern University of Science and Technology School of Chemistry and Pharmaceutical Sciences State Key Laboratory for Chemistry and Molecular Engineering of Medicinal ResourcesGuangxi Normal University School of Pharmaceutical Science Hengyang Medical School University of South China

Studying molecular recognition in aqueous environments is crucial for understanding biological processes. Herein, we present a series of N-doped endo-functionalized anthracene-based cavities by introducing inward-directed pyridine units. The subtle modifications can significantly affect the binding properties of these receptors, which is similar to the mutations in biological systems. Combining theoretical calculations and molecular recognition experiments demonstrated that these “mutations” have an impact on the hydrophobicity and charge distribution of the hosts, consequently significantly influencing molecular *** is crucial for understanding the intricate mechanisms of molecular-level interactions in biological receptors.

关键词： host-guest interaction hydrophobic effect endo-functionalized cavity mutation pyridine