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改进注意力机制嵌入PR-Net模型的水稻病害识别仿真
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作者 路阳 刘鹏飞 +3 位作者 许思源 刘启旺 顾福谦 王鹏 《系统仿真学报》 CAS CSCD 北大核心 2024年第6期1322-1333,共12页
针对现有的CNN模型在水稻叶部病害的识别中准确率较低的问题,提出了一种结合并行结构和残差结构的混合卷积神经网络模型PRC-Net(parallel residual with coordinate attention network)。引入并行结构,提高卷积的感受野;结合残差结构,... 针对现有的CNN模型在水稻叶部病害的识别中准确率较低的问题,提出了一种结合并行结构和残差结构的混合卷积神经网络模型PRC-Net(parallel residual with coordinate attention network)。引入并行结构,提高卷积的感受野;结合残差结构,使特征信息完整的连续传递;在骨干模型PR-Net中嵌入改进的空间注意力机制,增强对不同尺度病斑特征信息的凝聚程度;为进一步提升病害识别的准确率,并减少模型的训练时间和推理时间,通过改变加权方式对模型结构进行优化。仿真结果表明:与InceptionResNetV2等分类模型相比,PRC-Net具有更少的训练参数、更短的训练时间和更高的识别精度,性能优于其他作物病害识别模型。 展开更多
关键词 水稻叶部病害 PRC-Net(parallel residual with coordinate attention network) 卷积神经网络 注意力机制 图像识别
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Dynamic Cell Range Expansion-based Interference Coordination Scheme in Next Generation Wireless Networks 被引量:1
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作者 NING Zhaolong SONG Qingyang GUO Lei DAI Mengfan YUE Minghong 《China Communications》 SCIE CSCD 2014年第5期98-104,共7页
Deploying Picocell Base Station(PBS) throughout a Macrocell is a promising solution for capacity improvement in the next generation wireless networks.However,the strong received power from Macrocell Base Station(MBS) ... Deploying Picocell Base Station(PBS) throughout a Macrocell is a promising solution for capacity improvement in the next generation wireless networks.However,the strong received power from Macrocell Base Station(MBS) makes the areas of Picocell narrow and limits the gain of cell splitting.In this paper,we firstly propose a Dynamic Cell Range Expansion(DCRE) strategy.By expanding the coverage of the cell,we aim to balance the network load between MBS and PBS.Then,we present a cooperative Resource block and Power Allocation Scheme(coRPAS)based on DCRE.The objective of coRPAS is to decrease interference caused by MBS and Macrocell User Equipments,by which we can expand regions of Picocell User Equipments.Simulation results demonstrate the superiority of our method through comparing with other existing methods. 展开更多
关键词 Interference coordination heterogonous network cell range expansion.
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Hetero-bimetallic Complex of a 2D Coordination Network Constructed by Sodium Ion and p-Sulfonatothiacalix[4]arene
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作者 郭倩玲 屈一新 马淑兰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第7期767-772,共6页
A 2D coordination polymer built by sodium ion and water-soluble p-sulfonatothiacalix[4]arene of trivalent yttrium complex [Na(H2O)2Y(H2O)6(DMF) (p-sulfonatothiaca lix[4]arene)]-9H2O is reported. The complex be... A 2D coordination polymer built by sodium ion and water-soluble p-sulfonatothiacalix[4]arene of trivalent yttrium complex [Na(H2O)2Y(H2O)6(DMF) (p-sulfonatothiaca lix[4]arene)]-9H2O is reported. The complex belongs to the monoclinic system, space group P2 1/c, with a = 16.703(3), b = 17.819(4), c = 17.357(4)A, β = 106.23(3)°, Z = 4, V = 4960.0(17)A^3, Mr = 1304.08, Dc = 1.746 g/cm^3,μ= 1.624 mm^-1, F(000) = 2688, the final R = 0.0398 and wR = 0.1132 for 7534 observed reflections with I 〉 2σ(I). One yttrium(Ⅲ) ion is coordinated by the thiacalixarene ligand via the sulfonato group, and also ligated by an oxygen atom of a DMF molecule occupying the cavity of thiacalixarene and six aqua ligands. 展开更多
关键词 arene hetero-bimetallic complex 2D coordination network crystal structure
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Virtual network mapping algorithm for large-scale network environment
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作者 张顺利 邱雪松 孟洛明 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第4期55-63,共9页
A major challenge of network virtualization is the virtual network resource allocation problem that deals with efficient mapping of virtual nodes and virtual links onto the substrate network resources. However, the ex... A major challenge of network virtualization is the virtual network resource allocation problem that deals with efficient mapping of virtual nodes and virtual links onto the substrate network resources. However, the existing algorithms are almost concentrated on the randomly small-scale network topology, which is not suitable for practical large-scale network environments, because more time is spent on traversing SN and VN, resulting in VN requests congestion. To address this problem, virtual network mapping algorithm is proposed for large-scale network based on small-world characteristic of complex network and network coordinate system. Compared our algorithm with algorithm D-ViNE, experimental results show that our algorithm improves the overall performance. 展开更多
关键词 network virtualization virtual network mapping complex network network coordinate system simulated annealing algorithm
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Construction and the Second-order Nonlinear Optics of a New Chiral Coordination Network Based on Two Types of Homo-chiral Helices
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作者 黄永清 王阳 +3 位作者 郭秉林 刘承龙 李宗阁 赵越 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第7期1172-1178,共7页
A new 2D chiral cadmium coordination network [Cd(TCBA)2]?2EtOH (1) was prepared by the reaction of achiral angular asymmetric bridging ligand 2-((3,5-dimethyl- 4H-1,2,4-triazol-4-yl)-carbamoyl)-benzoic acid ... A new 2D chiral cadmium coordination network [Cd(TCBA)2]?2EtOH (1) was prepared by the reaction of achiral angular asymmetric bridging ligand 2-((3,5-dimethyl- 4H-1,2,4-triazol-4-yl)-carbamoyl)-benzoic acid (TCBA) with cadmium acetate, which was structurally characterized by IR, elemental analysis, thermogravimetric analysis and single-crystal X-ray diffraction. Complex 1 crystallizes in the chiral space group P21 and features a 2D chiral network consisting of two types of homo-chiral helices, which are further extended into a 3D chiral framework along the a-axis via hydrogen bonds. Moreover, powder second-order nonlinear optical (NLO) measurements reveal complex 1 has a modest second-harmonic-generation (SHG) efficiency at room temperature. 展开更多
关键词 cadmium(Ⅱ) chiral helix SHG activity coordination network crystal structure
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Coordinated and Balanced Growth Between Telecom Networks and Internet
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作者 Xu Heyuan (Institute of Communication Standards Research, China Academy of Telecommunication Research, MIIT, Beijing 100045, P.R.China) 《ZTE Communications》 2008年第4期6-10,共5页
As two existing networks, the telecom network and the Internet differ greatly in terms of business patterns, service quality, security and regulations, whilst technical development makes services provided by the two n... As two existing networks, the telecom network and the Internet differ greatly in terms of business patterns, service quality, security and regulations, whilst technical development makes services provided by the two networks penetrate each other. This article describes the status quo of the telecom network and the Internet as well as the problems faced by each of them, analyzes the causes of those problems, and makes suggestions on coordinated and balanced development of the telecom network and the Internet. 展开更多
关键词 NGN ITU As Coordinated and Balanced Growth Between Telecom networks and Internet
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Study on Coordinated Development of Regions Based on the Construction of Enterprise Value Network
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作者 Yulong Hao Wei Cui 《Chinese Business Review》 2005年第4期36-40,共5页
Under the background of constructing harmonious economic society, how to realize the coordinated development of regions in the course of region integration is a key problem. According to the relevant theory of enterpr... Under the background of constructing harmonious economic society, how to realize the coordinated development of regions in the course of region integration is a key problem. According to the relevant theory of enterprise gene reconfiguration and enterprise value network construction, we analyzed the problems in the merging course between the value network construction and region economic growth. Finally, we put forward the basic path of coordinated development of regions. 展开更多
关键词 enterprises value network region development regional coordination
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Method to generate training samples for neural network used in target recognition
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作者 何灏 罗庆生 +2 位作者 罗霄 徐如强 李钢 《Journal of Beijing Institute of Technology》 EI CAS 2012年第3期400-407,共8页
Training neural network to recognize targets needs a lot of samples.People usually get these samples in a non-systematic way,which can miss or overemphasize some target information.To improve this situation,a new meth... Training neural network to recognize targets needs a lot of samples.People usually get these samples in a non-systematic way,which can miss or overemphasize some target information.To improve this situation,a new method based on virtual model and invariant moments was proposed to generate training samples.The method was composed of the following steps:use computer and simulation software to build target object's virtual model and then simulate the environment,light condition,camera parameter,etc.;rotate the model by spin and nutation of inclination to get the image sequence by virtual camera;preprocess each image and transfer them into binary image;calculate the invariant moments for each image and get a vectors' sequence.The vectors' sequence which was proved to be complete became the training samples together with the target outputs.The simulated results showed that the proposed method could be used to recognize the real targets and improve the accuracy of target recognition effectively when the sampling interval was short enough and the circumstance simulation was close enough. 展开更多
关键词 pattern recognition training samples for neural network model emulation space coordinate transform invariant moments
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Tuning the local coordination environment of silver(Ⅰ) coordination networks with counterions for enhanced electrocatalytic CO_(2) reduction
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作者 Xiaofeng Cui Xueting Wang +4 位作者 Cong Fu Bing Liu Mei-Yan Gao Tingting Kong Yujie Xiong 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第5期1524-1530,共7页
Very recently, the local coordination environment of active sites has been found to strongly influence their performance in electrocatalytic CO_(2) reduction by tuning the intrinsic kinetics of CO_(2) activation and i... Very recently, the local coordination environment of active sites has been found to strongly influence their performance in electrocatalytic CO_(2) reduction by tuning the intrinsic kinetics of CO_(2) activation and intermediate stabilization. It is imperative to elucidate the mechanism for such an influence towards the rational design of efficient catalysts;however, the complex interactions between the multiple factors involved in the system make it challenging to establish a clear structure–performance relationship. In this work, we chose ion-intercalated silver(I)-based coordination networks(AgCNs) with a well-defined structure as a model platform, which enables us to understand the regulation mechanism of counterions as the counterions are the only tuning factor involved in such a system. We prepared two isostructural Ag CNs with different intercalation ions or counterions of BF_(4)^(-) and ClO_(4)^(-)(named as AgCNs-BF_(4) and AgCNs-ClO_(4)) and found that the former has a more competitive CO_(2) electroreduction performance than the latter. AgCNs-BF_(4) achieves the highest Faradaic efficiency for CO_(2) to CO of 87.1% at-1.0 V(vs. RHE) with a higher partial current density, while AgCNs-ClO_(4) exhibits only 77.2% at the same applied potential.Spectroscopic characterizations and theoretical calculation reveal that the presence of BF_(4)^(-)is more favorable for stabilizing the COOH^(*) intermediate by weakening hydrogen bonds, which accounts for the superior activity of Ag CNs-BF_(4). 展开更多
关键词 electrocatalytic CO_(2) reduction coordination networks local environment COUNTERIONS intercalation ions
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A Metal-organic Framework with Alternately Hydrophilic and Hydrophobic Layers Based on Tetrazole Derivative:Synthesis,Structure and Luminescent Property
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作者 梁晓强 樊增禄 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第12期1901-1907,共7页
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.... 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. 展开更多
关键词 coordination network ethyltetrazole-5-acetate fluorescence hydrophilic interaction hydrophobic effect
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PARAMETER COORDINATION AND ROBUST OPTIMIZATION FOR MULTIDISCIPLINARY DESIGN
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作者 HU Jie PENG Yinghong XIONG Guangleng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第3期368-372,共5页
A new parameter coordination and robust optimization approach for multidisciplinary design is presented. Firstly, the constraints network model is established to support engineering change, coordination and optimizati... A new parameter coordination and robust optimization approach for multidisciplinary design is presented. Firstly, the constraints network model is established to support engineering change, coordination and optimization. In this model, interval boxes are adopted to describe the uncertainty of design parameters quantitatively to enhance the design robustness. Secondly, the parameter coordination method is presented to solve the constraints network model, monitor the potential conflicts due to engineering changes, and obtain the consistency solution space corresponding to the given product specifications. Finally, the robust parameter optimization model is established, and genetic arithmetic is used to obtain the robust optimization parameter. An example of bogie design is analyzed to show the scheme to be effective. 展开更多
关键词 Constraints network Parameter coordination Robust design Multidisciplinary design
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A square lattice topology coordination network that exhibits highly selectiveC_(2)H_(2)/CO_(2)separation performance 被引量:1
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作者 Naveen Kumar Soumya Mukherjee +8 位作者 Andrey A.Bezrukov Matthias Vandichel Mohana Shivanna Debobroto Sensharma Alankriti Bajpai Victoria Gascón Ken‐ichi Otake Susumu Kitagawa Michael J.Zaworotko 《SmartMat》 2020年第1期48-55,共8页
C_(2)H_(2)/CO_(2)separation is an industrially important process that remains challenging because of the similar physicochemical properties of C_(2)H_(2)and CO_(2).We herein report that the new square lattice(sql)coor... C_(2)H_(2)/CO_(2)separation is an industrially important process that remains challenging because of the similar physicochemical properties of C_(2)H_(2)and CO_(2).We herein report that the new square lattice(sql)coordination network[Cu(bipy‐xylene)2(NO3)2]n,sql‐16‐Cu‐NO3,16=bipy‐xylene=4,4′‐(2,5‐dimethyl‐1,4‐phenylene)dipyridine,exists in at least three forms,as‐synthesised(α),activated(α′)and hydrated(β).The activated phase,sql‐16‐Cu‐NO3‐α′,is an ultramicroporous material that exhibits high selectivity towards C_(2)H_(2)over CO_(2)as revealed by dynamic gas breakthrough experiments(1:1,C_(2)H_(2)/CO_(2))that afforded 99.87%pure CO_(2)in the effluent stream.The separation selectivity at 298 K and 1 bar,78,is the third best value yet reported for C_(2)H_(2)selective physisorbents whereas the mid‐loading performance sets a new benchmark.The performance of sql‐16‐Cu‐NO3‐α′is attributed to a new type of C_(2)H_(2)binding site in which CH···ONO2 interactions enable moderately strong sorbent‐sorbate binding(Qst(C_(2)H_(2))=38.6 kJ/mol)at low loading.Conversely,weak CO_(2)binding(Qst(CO_(2))=25.6 kJ/mol)at low loading means that(ΔQst)AC[Qst(C_(2)H_(2))–Qst(CO_(2))]is 13 kJ/mol at low coverage and 11.4 kJ/mol at mid‐loading.Analysis of in situ powder X‐ray diffraction and modelling experiments provide insight into the sorption properties and high C_(2)H_(2)/CO_(2)separation performance of sql‐16‐Cu‐NO3‐α′. 展开更多
关键词 ACETYLENE ADSORPTION coordination networks crystal engineering ultramicroporosity
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A coordination compound featuring a supramolecular hydrogen-bonding network for proton conduction 被引量:1
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作者 Wen-He Wang Qiang Gao +5 位作者 Ai-Lin Li Yan-Yuan Jia Shi-Yu Zhang Jian-Hong Wang Ying-Hui Zhang Xian-He Bu 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第2期336-338,共3页
A new coordination compound [Mg(L)(H2 O)5·H2 O](NKU-109, H2 L=5-(4 H-1,2,4-triazol-4-yl)benzene-1,3-dicarboxylic acid) was solvothermally synthesized, featuring a supramolecular hydrogen-bonding network. ... A new coordination compound [Mg(L)(H2 O)5·H2 O](NKU-109, H2 L=5-(4 H-1,2,4-triazol-4-yl)benzene-1,3-dicarboxylic acid) was solvothermally synthesized, featuring a supramolecular hydrogen-bonding network. A good proton conductivity of 5.87×10^-4S/cm was recorded at 70℃ and a relative humidity of75% in alternating current(AC) impedance experiment, which sheds a new light on the design of proton conduction materials based on coordination compounds. 展开更多
关键词 Coordination compound Fuel cell Hydrogen-bonding network Supramolecular Proton conductivity
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Visible and near-infrared luminescence of polycatenated cationic pyridinone lanthanide networks
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作者 Yubo Shu Weisheng Liu 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第4期436-441,共6页
A series of isomorphic lanthanide coordination polymers [Ln(Ⅲ)(MBP)2(NO3)2(Br)- 2C3H60] [Ln=Eu, Tb, Er, Yb, and Gd; MBP=N,N'-methylene-bis(pyridin-4-0ne)] featuring polycatenated sql cationic network and i... A series of isomorphic lanthanide coordination polymers [Ln(Ⅲ)(MBP)2(NO3)2(Br)- 2C3H60] [Ln=Eu, Tb, Er, Yb, and Gd; MBP=N,N'-methylene-bis(pyridin-4-0ne)] featuring polycatenated sql cationic network and incorporated bromide counter ion were prepared. Their visible and near-infrared (NIR) luminescence properties were characterized by steady-state excitation and emission spectra, as well as luminescence lifetimes and quantum yields. The D2d dodecahedron coordination geometry causes visible light excitations and strongly monochromatic emissions. The external heavy-atom environment induces remarkable en- hancement on the NIR emissions. The sensitization processes are revealed by analyzing the electronic properties of MBP ligand. 展开更多
关键词 coordination network LANTHANIDE pyridinone LUMINESCENCE
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Joint load balancing and interference coordination in multi-antenna heterogeneous networks 被引量:2
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作者 Zhu Wenfeng Qiu Ling +1 位作者 Chen Zheng Liang Xiaowen 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2016年第6期34-40,共7页
In heterogeneous networks(Het Nets), it is desirable to offload users from macro cells to small cells to achieve load balancing. However, the offloaded users suffer a strong inter-tier interference. To guarantee the... In heterogeneous networks(Het Nets), it is desirable to offload users from macro cells to small cells to achieve load balancing. However, the offloaded users suffer a strong inter-tier interference. To guarantee the performance of the offloaded users, the interference from macro cells should be carefully managed. In this paper, we jointly optimize load balancing and interference coordination in multi-antenna Het Nets. Different from previous works, instead of almost blank subframes(ABS) on which the macro cells waste time resource, the macro cells suppress the interference to the offloaded users by zero-forcing beamforming(ZFBF) on interference nulling subframes(INS). Considering user association cannot be conduct frequently, we derive the long-term throughput of users over Rayleigh fading channels while previous works focused on instantaneous rate. From the perspective of the spectrum efficiency and user fairness, we formulate a long-term network-wide utility maximization problem. By decomposing the problem into two subproblems, we propose an efficient joint load balancing and interference coordination strategy. Simulation results show that our proposal can achieve good system performance gains over counterparts in term of the network utility, cell edge throughput and average throughput. 展开更多
关键词 heterogeneous networks multi-antenna load balancing interference coordination zero-forcing beamforming
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H_(2)S-Activated“One-Key Triple-Lock”Bis-Metal Coordination Network for Visualizing Precise Therapy of Colon Cancer
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作者 Cheng Zhang Jiaqi Li +6 位作者 Chang Lu Tengxiang Yang Yan Zhao Lili Teng Yue Yang Guosheng Song Xiao-Bing Zhang 《CCS Chemistry》 CAS 2021年第8期2126-2142,共17页
Colon cancer is the third most common malignancy and the fourth most prevalent cause of death worldwide.Unfortunately,current cancer treatment approaches suffer from low specificity toward colon cancers and lack of fa... Colon cancer is the third most common malignancy and the fourth most prevalent cause of death worldwide.Unfortunately,current cancer treatment approaches suffer from low specificity toward colon cancers and lack of facile imagingmethod to monitor a real-time therapeutic process,usually resulting in severe toxicity to normal tissues. 展开更多
关键词 ultrathin coordination network molecular dipoles magnetic resonance imaging photodynamic therapy fluorescence
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The catassembled generation of naphthalene diimide coordination networks with lone pair-π interactions
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作者 Yong Chen Jian-Jun Liu +2 位作者 Chang-Rong Fan Jun-Qian Li Mei-Jin Lin 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第11期1492-1497,共6页
Catassembly is a new concept in molecular assembly that is analogous to catalysis in chemical synthesis. However, for most molecular-assembled processes, the catassembler contributions are rather inconspicuous due to ... Catassembly is a new concept in molecular assembly that is analogous to catalysis in chemical synthesis. However, for most molecular-assembled processes, the catassembler contributions are rather inconspicuous due to the low activation barriers. As a result, few systems dealing with the catassembly are available until now. In this paper, we report that naphthalene diimide coordination networks are formed under the catassembly of lone-pair-bearing catassemblers(e.g., N,N-dimethylacetamide, N-methylpyrrolidin-2-one). During such molecular assembly, a stable transition state between the electron-deficient naphthalene diimide tectons and catassemblers via the less common lone pair-π interactions was observed, which is supposed to play the key role in the enhancement of coordination abilities of organic tectons and thus formation of the final coordination networks. 展开更多
关键词 catassembly coordination network naphthalene diimide lone pair-π interaction
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A new 8-connected self-penetrating metal-organic framework based on dinuclear cadmium clusters as secondary building units 被引量:4
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作者 Kun-Huan He Yun-Wu Li +1 位作者 Yong-Qiang Chen Ze Chang 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第8期691-694,共4页
A new metal-organic framework(MOF) based on metal clusters as secondary building units(SBU),has been synthesized and structurally characterized.The reported MOF presents an interesting 8-connected self-penetrating... A new metal-organic framework(MOF) based on metal clusters as secondary building units(SBU),has been synthesized and structurally characterized.The reported MOF presents an interesting 8-connected self-penetrating coordination network based on dinuclear cadmium cluster with a 4^(24)·5·6~3 topology. Moreover,the thermal stability and luminescence property of this compound have been investigated. 展开更多
关键词 Metal-organic framework Secondary building units Coordination network Luminescence property
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Synthesis, Structure and Coordination Self-Assembly of Azacalix[4-n] pyridine[n] pyrazi nes (n=1 -- 3)
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作者 Jincheng Wu Liang Zhao +1 位作者 Dexian Wang Meixiang Wang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2013年第5期589-597,共9页
We herein report the synthesis and metal-directed coordination self-assembly behaviors of three new macrocyc- lic azacalix[4]aromatics that comprise various numbers of pyridine and pyrazine rings bridged by N-CH3 grou... We herein report the synthesis and metal-directed coordination self-assembly behaviors of three new macrocyc- lic azacalix[4]aromatics that comprise various numbers of pyridine and pyrazine rings bridged by N-CH3 groups. Structural characterization of 1--3 explored that their conformations are fluxional in solution and each adopts a 1,3-alternate configuration in crystalline solids. The macrocyclic skeletons in azacalixaromatic 1--3 afford a good platform to designedly arrange coordination sites in a unique way relative to conventional multidentate ligands. Solid-state structures of three coordination self-assembled silver complexes (13--15) of 1 --3 determined by X-ray crystallography suggest that the nitrogen atoms on procumbent aromatics have better coordination ability than those on perpendicular aromatics and dictate the whole coordination self-assemblies. Unique discrete and 1D chain-like structures were thus obtained. This system may afford a deeper insight into the coordination self-assembly studies of heteroatom-bridged calixaromatics, possibly extending potential application of this novel macrocyclic polyden- tate organic compounds in the synthesis of functional metal organic framework formation. 展开更多
关键词 CALIXARENES coordination networks SELF-ASSEMBLY MACROCYCLIC PYRAZINE
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Nitrogen-rich porphyrinic metal-organic frameworks synthesized by postsynthetic metathesis: from inert material to active catalyst
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作者 Dahuan Liu Xuan Wang +3 位作者 Ying-Pin Chen Shuai Yuan Chongli Zhong Hong-Cai Zhou 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第8期975-979,共5页
With the aid of a postsynthetic metathesis method, an inert nitrogen-rich porphyrinic metal-organic framework can exhibit a high catalytic activity in one-pot deacetalization-Knoevenagel condensation reaction.
关键词 metal-organic frameworks porous coordination network post-synthetic metathesis CATALYSIS TETRAZOLATE
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