检索结果-南通市图书馆

Radical organometallic nanocages with redox switchable poly-NHC ligands

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2023年第7期16卷 10678-10683页

作者： Guang-Feng Jin Yan-Zhen Zhang Le Yu Wei-Ling Jiang Yang Li Li-Ying Sun Peng Li Ying-Feng Han Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200438China

Developing discrete radical organometallic nanocages is essential for fabricating functional materials.In this study,we construct a series of poly-NHC-based(NHC=N-heterocyclic carbene)organometallic nanocages 3a-3c with different sizes by employing redox-active bis(triarylamine)derivatives with differentπ-conjugated spacers as building blocks.The varied sizes of nanocages 3a-3c modulate the distance of the redox-active centers and reversibly convert them to radical nanocages 3a^(2+)-3c^(2+)through chemical and electrochemical oxidation.Radical nanocages 3a^(2+)-3c^(2+)display clear bond and angle alteration and retention of their three-dimensional topologies.This work not only merely proves that these nanocages are excellent stimulus-responsive materials but also opens a door to the rational design of novel radical organometallic nanocages.

关键词： stimuli-responsive organometallic nanocage N-heterocyclic carbene radical

Structural Characterization and Proton-conductive Property of a Lanthanide Metal-organic Framework Assembled from 1,2,4,5-Benzenetetracarboxylic Acid and Piperazine

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2017年第6期36卷 977-984页

作者：梁晓强樊增禄 College of Environmental and Chemical Engineering Xi'an Polytechnic University State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Nanjing University College of Textile & Material Xi'an Polytechnic University

The reaction of Pr（Ⅲ） salt with 1,2,4,5-benzenetetracarboxylic acid（H4betc） and piperazine（pip） yielded a lanthanide metal-organic framework {[Pr（betc）（H2O）2]（H2pip）0.5}n（1）under hydrothermal conditions. Compound 1 was characterized by single-crystal X-ray structural analysis, elemental analysis, IR, X-ray powder diffraction, and thermal gravimetric. Compound 1crystallizes in monoclinic, space group P21/n with a = 11.023（5）, b = 11.109（5）, c = 11.456（5） A, β = 110.065（5）°, V = 1317.7（9） A3, Mr = 471.14, Z = 4, F（000） = 920, Dc = 2.375 g/cm^3, μ（Mo Kα） = 3.761 mm-1, the final R = 0.0286 and w R = 0.0821（I 〉 2σ（I））. Compound 1 exhibits a 2D network with（4, 4） topology, and a 3D supramolecular framework formed by hydrogen-bonding interactions. The proton conductivity of compound 1 has been investigated at ~97% relative humidity and different temperature.

关键词： lanthanide metal-organic framework, 1,2,4,5-benzenetetracarboxylic acid,protonated piperazine, hydrogen bond, proton conductivity

Hydrothermal Synthesis,Crystal Structure and Proton Conductivity of a Pr–Ca Heterometal-organic Framework Generated by 1,2,4,5-Benzenetetracarboxylic Acid

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2017年第6期36卷 993-1002页

作者：梁晓强李仁忠樊增禄 College of Environmental and Chemical Engineering Xi'an Polytechnic University State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Nanjing University College of Electronics and Information Xi'an Polytechnic University College of Textile & Material Xi'an Polytechnic University

A heterometal-organic framework {[Pr2Ca（betc）2（H2O）7]·H2O}n（1） was prepared by the hydrothermal reaction of 1,2,4,5-benzenetetracarboxylic acid（H4betc） with Pr（NO3）3 and CaCO3, and further characterized by single-crystal X-ray structural analysis, elemental analysis, IR, thermal gravimetric, and X-ray powder diffraction. Complex 1 crystallizes in triclinic, space group P1 with a = 7.3668（12）, b = 10.1726（14）, c = 11.2264（15） A, a = 100.404（2）, b = 106.113（3）, g = 109.158（3）o, V = 728.48（19） A3, Mr = 966.26, Z = 1, F（000） = 470, Dc = 2.203 g/cm3, m（Mo Kα） = 3.585 mm-1, the final R = 0.0195 and w R = 0.0470（I 〉 2s（I））. Complex 1 is a 3D network with pcu topology with 1D porosity and rich hydrogen-bonding interactions. The proton conductivity of complex 1 was also studied under ~97% relative humidity and the different temperature conditions.

关键词： 3D heterometal-organic framework 1,2,4,5-benzenetetracarboxylic acid 1Dchannel hydrogen bond proton conduction

An 8-Connected Chiral Lanthanide Metal-organic Framework Constructed from Naturally Camphoric Acid:Crystal Structure,Vibrational Circular Dichroism Spectroscopy and Second-order Nonlinear Optical Effect

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2016年第11期35卷 1736-1744页

作者：梁晓强吴涛樊增禄 College of Environmental and Chemical Engineering Xi’an Polytechnic University State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing University College of Textile & Material Xi'an Polytechnic University

A chiral lanthanide metal-organic framework based on enantiopure camphoric acid （D-H2cam）, [Nd3（D-cam）8（H2O）4Cl]n （1）, has been synthesized and characterized by single-crystal X-ray structural analysis, elemental analysis, IR, thermal gravimetric, and X-ray powder diffraction. Crystal data for the title compound are as follows： orthorhombic system, space group P212121 with a = 13.8287（7）, b = 14.0715（7）, c = 25.7403（12） A^°, V = 5008.8（4） A^°3, Mr = 1333.08, Z = 4, F（000） = 2644, Dc = 1.768 g/cm^3, μ（MoKα） = 3.189 mm^-1, the final R = 0.0351 and wR = 0.0814 （I 〉 2σ（I））. Compound 1 displays an 8-connected bcu topology 3D framework and hydrogen-bonding interactions stabilize the solid-state structure. The vibrational circular dichroism （VCD） spectrum and second-order nonlinear optical effect of compound 1 have been studied in the solid state.

关键词： homochiral lanthanide metal-organic framework D-camphoric acid 8-connected,VCD spectrum second-order nonlinear optical effect

MFSR: Maximum Feature Score Region-based Captions Locating in News Video Images

在线全文

学校读者我要写书评

暂无评论

International Journal of Automation and computing 2018年第4期15卷 454-461页

作者： Zhi-Heng Wang Chao Guo Hong-Min Liu Zhan-Qiang Huo School of Computer Science and Technology Henan Polytechnic University

For news video images, caption recognizing is a useful and important step for content understanding. Caption locating is usually the first step of caption recognizing and this paper proposes a simple but effective caption locating algorithm called maximum feature score region （MFSR） based method, which mainly consists of two stages： In the first stage, up/down boundaries are attained by turning to edge map projection. Then, maximum feature score region is defined and left/right boundaries are achieved by utilizing MFSR. Experiments show that the proposed MFSR based method has superior and robust performance on news video images of different types.

关键词： News video images captions recognizing captions locating content understanding maximum feature score region（MFSR）.

Wet spinning of fiber-shaped flexible Zn-ion batteries toward wearable energy storage

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2022年第8期31卷 192-200,I0006页

作者： Tingting Gao Guangyuan Yan xin Yang Qing Yan Yankuan Tian Jianwei Song Faxue Li Xueli Wang Jianyong Yu Yiju Li Shaojun Guo Key Laboratory of Textile Science and Technology Ministry of EducationCollege of TextilesDonghua UniversityShanghai 201620China Innovation Center for Textile Science and Technology Donghua UniversityShanghai 201620China School of Materials Science and Engineering Peking UniversityBeijing 100871China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049ShaanxiChina School of Biological and Chemical Engineering NingboTech UniversityNingbo 315100ZhejiangChina

High-performance flexible one-dimensional(1D)electrochemical energy storage devices are crucial for the applications of wearable electronics.Although much progress on various 1D energy storage devices has been made,challenges involving fabrication cost,scalability,and efficiency remain.Herein,a highperformance flexible all-fiber zinc-ion battery(ZIB)is fabricated using a low-cost,scalable,and efficient continuous wet-spinning method.Viscous composite inks containing cellulose nanofibers/carbon nanotubes(CNFs/CNTs)binary composite network and either manganese dioxide nanowires(MnO_(2) NWs)or commercial Zn powders are utilized to spinning fiber cathodes and anodes,respectively.MnO_(2) NWs and Zn powders are uniformly dispersed in the interpenetrated CNFs/CNTs fibrous network,leading to homogenous composite inks with an ideal shear-thinning property.The obtained fiber electrodes demonstrate favorable uniformity and flexibility.Benefiting from the well-designed electrodes,the assembled flexible fiber-shaped ZIB delivers a high specific capacity of 281.5 m Ah g^(-1) at 0.25 A g^(-1) and displays excellent cycling stability over 400 cycles.Moreover,the wet-spun fiber-shaped ZIBs achieve ultrahigh gravimetric and volumetric energy densities of 47.3 Wh kg^(-1) and 131.3 m Wh cm^(-3),respectively,based on both cathode and anode and maintain favorable stability even after 4000 bending cycles.This work offers a new concept design of 1D flexible ZIBs that can be potentially incorporated into commercial textiles for wearable and portable electronics.

关键词： Manufacturing Wet spinning Zn ion battery Nanocellulose Fiber

二元金属硫族化合物在能源储存体系中的作用:挑战和可能的解决策略

在线全文

学校读者我要写书评

暂无评论

Science China Materials 2022年第3期65卷 559-592页

作者： Yousaf Muhammad Naseer Ufra Ali Imran 李一举 Aftab Waseem Mahmood Asif Mahmood Nasir 高鹏姜银珠郭少军 School of Materials Science and Engineering International Center for Quantum Materials and Electron Microscopy LaboratorySchool of PhysicsPeking UniversityBeijing 100871China ZJU-Hangzhou Global Scientific and Technological Innovation Centre Zhejiang UniversityHangzhou 311200China State Key Laboratory of Resources and Environment Information System Institute of Geographical Sciences&Natural Resources ResearchChinese Academy of SciencesBeijing 100871China School of Chemical and Biomolecular Engineering The University of SydneyDarlingtonSydneyNew South Wales2006Australia School of Engineering RMIT University124 La Trobe StreetMelbourneVictoria3001Australia School of Materials Science and Engineering State Key Laboratory of Clean Energy UtilizationZhejiang UniversityHangzhou 310027China

二元金属硫族化合物由于其丰富的相界面、高活性位点、优异的导电性以及快速的电化学动力学,与单金属硫族化合物相比具有更加优异的电化学性能.然而,材料的本征离子电导率低,在充放电过程中结构发生反复的团聚与断裂,体积膨胀大等因素... 详细信息

二元金属硫族化合物由于其丰富的相界面、高活性位点、优异的导电性以及快速的电化学动力学,与单金属硫族化合物相比具有更加优异的电化学性能.然而,材料的本征离子电导率低,在充放电过程中结构发生反复的团聚与断裂,体积膨胀大等因素导致其电化学性能衰减严重.为了解决上述问题,诸多策略被提出并用于调控二元金属硫族化合物的纳米结构以获得优化的电极材料.但是目前依旧缺乏对二元金属硫族化合物电化学过程的系统认识,也因此限制了其大规模的商业化应用.在这篇综述中,我们不仅重点介绍了基于二元金属硫族化合物电极材料制备的最新研究进展,还通过解释二元金属硫族化合物的电化学动力学,进一步构建和理解了这类材料的构效关系.此外,我们讨论了通过纳米结构化和使用碳材料与三维模板与之形成复合材料的策略来调控和修饰二元金属硫族化合物,并将详细讨论二元金属硫族化合物在超级电容器、金属离子电池、金属空气电池以及碱金属电池等电化学能源储存体系中的工作机理.最后,我们总结了二元金属硫族化合物在发展实际能源器件的过程中面临的主要挑战及可能的解决策略.我们相信,这篇综述将对如何调控二元金属硫族化合物的理化性质以获得优异的电化学器件提供指导性建议.

关键词：金属空气电池超级电容器充放电过程电化学动力学电化学过程离子电导率商业化应用电化学性能

在线全文

学校读者我要写书评

暂无评论

冷热交变花岗岩的力学与损伤特性研究

Journal of Central South university 2023年第12期30卷 4082-4096页

作者：彭康任基王元民罗松龙坤 School of Resources and Safety Engineering Central South UniversityChangsha 410083China State Key Laboratory of Green and Low-carbon Development of Tar-rich Coal in Western China Xi’an University of TechnologyXi’an 710048China School of Civil Engineering Chongqing Jiaotong UniversityChongqing 400074China

为研究冷热交变岩石的力学性能和损伤演变规律,对冷热交变后的花岗岩进行单轴压缩试验和巴西劈裂试验,利用声发射监测和电镜扫描技术分析花岗岩加载过程中的声发射信号特征和试样破坏后的微观形态特征。结果表明,在不同冷热交变次数下,... 详细信息

为研究冷热交变岩石的力学性能和损伤演变规律,对冷热交变后的花岗岩进行单轴压缩试验和巴西劈裂试验,利用声发射监测和电镜扫描技术分析花岗岩加载过程中的声发射信号特征和试样破坏后的微观形态特征。结果表明,在不同冷热交变次数下,花岗岩的抗压强度与抗拉强度都明显降低,且两者呈显著的线性关系。在单轴压缩条件下,花岗岩的破坏模式以轴向劈裂破坏和剪切破坏为主;在巴西劈裂条件下,随着热处理温度的升高,花岗岩的破坏表现为径向破坏、径向弧形破坏和沿弱结构平面的混合破坏。两种实验条件下试样破坏过程中的声发射计数变化与应力−应变曲线变化基本一致。归一化累积声发射计数可以较好地反映试样加载过程中的损伤演变特征。试样的初始损伤随着温度和冷热交变次数的增加而增加,导致花岗岩在加载过程中的损伤率持续增长。此外,基于力学参数定义了三个损伤变量,其中基于抗拉强度的损伤变量对冷热交变次数最为敏感。

关键词：单轴压缩巴西劈裂岩石损伤声发射扫描电镜冷热交变

A Metal-organic Framework with Alternately Hydrophilic and Hydrophobic Layers Based on Tetrazole Derivative:Synthesis,Structure and Luminescent Property

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2015年第12期34卷 1901-1907页

作者：梁晓强樊增禄 College of Environmental and Chemical Engineering Xi’an Polytechnic University State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Nanjing University College of Textile & Material Xi'an Polytechnic University

A new metal-organic framework based on ethyl 1H-tetrazole-5-acetate （Hetza）, [Ag4（etza）4] （1）, has been synthesized and characterized by elemental analysis, IR, thermal gravimetric and X-ray structural analysis. Crystal data for the title complex are as follows： triclinic system, space group P1 with a = 11.0771（6）, b = 11.6636（6）, c = 13.2925（8）, a = 102.3710（10）, β =103.3810（10）, γ = 90.0890（10）°, V = 1629.60（16） A3, Mr = 1052.06, Z = 2, F（000） = 1024, Dc = 2.144 g/cm3, μ（MoKa） = 2.438 mm^-1, the final R = 0.0538 and wR = 0.1475 （I 〉 2σ（I））. Complex 1 adopts the （4.82） topological network and the alternately hydrophilic-hydrophilic and hydropho- bic-hydrophobic arrangements. The luminescent properties of complex 1 and the free Hetza ligand have been studied in the solid states.

关键词： coordination network ethyltetrazole-5-acetate fluorescence hydrophilic interaction hydrophobic effect