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Solid-state NMR for metal-containing zeolites:from active sites to reaction mechanism

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Frontiers of Chemical Science and Engineering 2020年第2期14卷 159-187页

作者： Xingling Zhao Jun Xu Feng Deng National Center for Magnetic Resonance in Wuhan State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsCAS Key Laboratory of Magnetic Resonance in Biological SystemsWuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China

metal-containing zeolite catalysts have found a wide range of applications in heterogeneous *** understand the nature of metal active sites and the reaction mechanism over such catalysts is of great importance for the establishment of structure-activity *** advanced solid-state NMR(SSNMR)spectroscopy is robust in the study of zeolites and zeolite-catalyzed *** this review,we summarize recent developments and applications of SSNMR for exploring the structure and property of active sites in metal-containing ***,detailed information on host-guest interactions in the relevant zeolite catalysis obtained by SSNMR is also ***,we highlight the mechanistic understanding of catalytic reactions on metal-containing zeolites based on the observation of key surface species and active intermediates.

关键词： metal-containing zeolites solid-state NMR active site host-guest interaction reaction mechanism

Electronic Structures and Conductivities of Fullerene C_(60) and metal-containing Fullerenes MC_(60) (M=Li, Na, K, Rb, Cs)

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Chinese Science Bulletin 1993年第7期38卷 568-571页

作者：严继民孔静 Institute of Chemistry Academia Sinica Beijing 100080 PRC

It has been reported recently that the solids KxC60 and RbxC60 （x=1→5） are conductors. If x=0 and 6, they are insulators, and if x=3, they have the largest conductivities. When the temperatures go down to 18K for solid KxC60 and 28K for solid RbxC60, they are transferred into superconductors. These results are very interesting. Solids KxC60 and RbxC60 are very unstable when being exposed to air, so for practical purposes, it had better be synthesized to the metal-containing fullerenes MC60 in which the metal atom M is at the center of C60. It has been known for some years

关键词： C60 MC60 fullerene metal-containing fullerenes electronic structure and conductivity.

Comparative Toxicity of Nanomaterials to Air-blood Barrier Permeability Using an In Vitro Model

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Biomedical and Environmental Sciences 2019年第8期32卷 602-613页

作者： ZHAO Kang Feng SONG Yu Qing ZHANG Rui Hua YANG Xiao Yan SUN Bo HOU Zhi Quan PU Xiao Ping DAI Hong Xing BAI Xue Tao Department of Environmental Toxicology National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijing 100021China Peking Union Medical College Beijing 100730China Research Institute of Chemical Defence Beijing 100083China Department of Chemical Engineering School of Environment and Energy EngineeringBeijing University of Technology Beijing 100124China Department of Molecular and Cellular Pharmacology School of Pharmaceutical SciencesPeking UniversityBeijing 100083China

Objective To comparatively study the toxicity of four metal-containing nanoparticles(MNPs) and their chemical counterparts to the air-blood barrier(ABB) permeability using an in vitro *** ABB model, which was developed via the co-culturing of A549 and pulmonary capillary endothelium, was exposed to spherical CuO-NPs(divided into CuO-40, CuO-80, and CuO-100 based on particle size), nano-Al2O3(sheet and short-rod-shaped), nano-ZnO, nano-Pb S, CuSO4, Al2(SO4)3, Zn(CH3COO)2, and Pb(NO3)2 for 60 *** 10 min following exposure, the cumulative cleared volume(ΔTCL) of Lucifer yellow by the model was calculated.A clearance curve was established using linear regression analysis of ΔTCL versus *** coefficient(P) was calculated based on the slope of the curve to represent the degree of change in the ABB *** The results found the increased P values of CuO-40, CuO-80, sheet, and short-rod-shaped nano-Al2O3, Al2(SO4)3, and Pb(NO3)*** them, small CuO-40 and CuO-80 were stronger than CuO-100 and CuSO4;no difference was observed between Al2(SO4)3 and sheet and short-rod-shaped nano-Al2O3;and nano-Pb S was slightly weaker than Pb(NO3)*** clearly the MNPs possess diverse *** ABB permeability abnormality means pulmonary toxicity *** studies are warranted to understand MNPs toxicity and ultimately control the health hazards.

关键词： Air-blood barrier In vitro model Permeability metal-containing nanoparticles (MNPs) Toxicity screening

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铕配合物与苯乙烯共聚物的研究(英文)

功能材料 2005年第7期36卷 1119-1121,1125页

作者：潘远凤郑安呐 XIAO Hui-ning 胡福增蔡平雄 .华东理工大学超细材料制备与应用教育部重点实验室上海200237 华东理工大学超细材料制备与应用教育部重点实验室上海200237 Department of Chemical Engineering University of New Brunswick Fredericton NB Canada E3B5A3

将具有聚合活性的稀土铕有机配合物Eu3+(BA)2(AA)(phen)与苯乙烯共聚得到一种半透明且发光强度高的稀土高分子光致发光材料,通过凝胶色谱、红外光谱、紫外光谱对其结构进行表征,证实是共聚物,而不是共混掺杂。通过荧光光谱分析说明只要... 详细信息

将具有聚合活性的稀土铕有机配合物Eu3+(BA)2(AA)(phen)与苯乙烯共聚得到一种半透明且发光强度高的稀土高分子光致发光材料,通过凝胶色谱、红外光谱、紫外光谱对其结构进行表征,证实是共聚物,而不是共混掺杂。通过荧光光谱分析说明只要引入少量的稀土配合物单体,共聚物就表现出配合物单体的强紫外吸收特性,并发射出Eu3+的特征荧光。热分析则表明共聚物引入稀土配合物基团后,其热稳定性得到了提高,而稀土配合物键合到大分子链后其结构单元热稳定性也得到相应的提高。

关键词： europium complexes rare earth metal-containing polymer fluorescence

Coordination Interaction between Rare Earth and/or Transition metal Centers and Thiophene Series Oligomer Derivatives in Ultrathin Langmuir-Blodgett Films

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Journal of Modern Physics 2013年第12期4卷 7-17页

作者： H. V. Grushevskaya I. V. Lipnevich T. I. Orekhovskaya Belarusian State University of Informatics and Radioelectronics Minsk Belarus Physics Department Belarusian State University Minsk Belarus

It has been shown by thermodynamic and electro-chemical methods that coordination interactions are involved in the process of incorporation of rare-earth elements and/or Fe into Langmuir monolayers of oligomer with alkyl fragment. A coordination mechanism, which is responsible for self-organization of octahedral Fe(II)-complexes of nano-cyclic ligands obtained from oligomer of thiophene pyrrole series derivatives in compressed Langmuir monolayers has been proposed. It has been established that a coordinational-polymeric hexagonal network of nano-cyclic ligands with metal centers is formed at the phase transition when compressing the Langmuir monolayers of thiophene pyrrole series oligomer with alkyl fragment on surface of subphase with rare-earth (Sm, Er, Ce) and/or Fe ions.

关键词： Langmuir Monolayer Self-Organization metal-containing Ultrathin Langmuir-Blodgett Film