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Coordinatively unsaturated sites in zeolite matrix: Construction and catalysis 被引量:7
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作者 Weijie Li Lanan Sun +3 位作者 Linjun Xie Xin Deng Naijia Guan Landong Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第9期1255-1281,共27页
Zeolites with ordered porous structure of molecular size are widely employed as commercial adsorbents and catalysts.On the other hand,the zeolite matrix is regarded as an ideal scaffold for hosting coordinatively unsa... Zeolites with ordered porous structure of molecular size are widely employed as commercial adsorbents and catalysts.On the other hand,the zeolite matrix is regarded as an ideal scaffold for hosting coordinatively unsaturated sites.Remarkable achievements have been made dealing with the construction,characterization and catalytic applications of coordinatively unsaturated sites in zeolite matrix.Herein,a literature overview of recent progresses on this important topic is presented from the specific view of coordination chemistry.Different strategies to construction coordinatively unsaturated sites in zeolite matrix,in zeolite framework or extraframework positions,are first introduced and their characteristics are compared.Then,spectroscopic techniques to determine the existing states of cation sites and their transformations in zeolite matrix are discussed.In the last section,the catalytic applications of coordinatively unsaturated sites in zeolite matrix for various important chemical transformations are summarized. 展开更多
关键词 coordinatively unsaturated sites Zeolite matrix CONSTRUCTION Characterization CATALYSIS
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Ultralow-Energy-Barrier H_(2)O_(2)Dissociation on Coordinatively Unsaturated Metal Centers in Binary Ce-Fe Prussian Blue Analogue for Efficient and Stable Photo-Fenton Catalysis
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作者 Wenting Zheng Hui Guo +4 位作者 Changqing Zhu Cailiang Yue Wenlei Zhu Fuqiang Liu Zhaoxu Chen 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第6期427-435,共9页
The low intrinsic activity of Fenton catalytic site and high demand for light-energy input inhibit the organic-pollution control efficiency of photo-Fenton process.Here,through structural design with density functiona... The low intrinsic activity of Fenton catalytic site and high demand for light-energy input inhibit the organic-pollution control efficiency of photo-Fenton process.Here,through structural design with density functional theory(DFT)calculations,Ce is predicted to enable the construction of coordinatively unsaturated metal centers(CUCs)in Prussian blue analogue(PBA),which can strongly adsorb H_(2)O_(2)and donate sufficient electrons for directly splitting the O-O bond to produceOH.Using a substitution-co-assembly strategy,binary Ce-Fe PBA is then prepared,which rapidly degrades sulfamethoxazole with the pseudo-first-order kinetic rate constant exceeding reported values by 1-2 orders of magnitude.Meanwhile,the photogenerated electrons reduce Fe(Ⅲ)and Ce(Ⅳ)to promote the metal valence cycle in CUCs and make sulfamethoxazole degradation efficiency only lose 6.04%in 5 runs.Overall,by introducing rare earth metals into transition metal-organic frameworks,this work guides the whole process for highly active CUCs from design and construction to mechanism exploration with DFT calculations,enabling ultrafast and stable photo-Fenton catalysis. 展开更多
关键词 Ce substitution coordinatively unsaturated metal centers PHOTO-FENTON Prussian blue analogue
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THE SYNTHESIS AND DIOXYGEN-AFFINITY OF SOME SCHIFF-BASE COBALT(Ⅱ)CHELATES COORDINATIVELY BOUND ON POLY(4-VINYLPYRIDINE-CO-STYRENE)
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作者 Jian Biao MA Cun Xiang ZHAO Jian Min LI LI Zhong XU Bing Lin HE Institute of Polymer Chemistry,Nankai University,Tianjin,300071 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第6期511-512,共2页
Some Schiff-base cobalt(Ⅱ)chelates like ethylenebis[(2-hydroxy-3- methoxy-5-methylphenyl)methylideneiminato]Cobalt(Ⅱ)were coordioatively anchored onto poly(4-vinylpyridine-co-styrene)in diglyme solution and the diox... Some Schiff-base cobalt(Ⅱ)chelates like ethylenebis[(2-hydroxy-3- methoxy-5-methylphenyl)methylideneiminato]Cobalt(Ⅱ)were coordioatively anchored onto poly(4-vinylpyridine-co-styrene)in diglyme solution and the dioxygen-affinity of the resulting polymeric complexes were measured in situ. 展开更多
关键词 CHELATES coordinatively BOUND ON POLY THE SYNTHESIS AND DIOXYGEN-AFFINITY OF SOME SCHIFF-BASE COBALT VINYLPYRIDINE-CO-STYRENE CO
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Phase-engineered coordinatively unsaturated metal sites in spinel oxides for robust Fenton-like catalysis
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作者 Jingjing Guo Ying Zhang +8 位作者 Jun Wang§ Jiankang Zheng Shi Zhang Ruilong Li Xiao Han Geng Wu Xiao-Cheng Liu Yang Mu Xun Hong 《Nano Research》 2025年第6期243-251,共9页
Coordinatively unsaturated metal sites(CUS)located at tetrahedral(T_(d))in spinel structure are highly effective for activating peroxymonosulfate(PMS)in Fenton-like catalysis.However,the conventional T_(d)-octahedral(... Coordinatively unsaturated metal sites(CUS)located at tetrahedral(T_(d))in spinel structure are highly effective for activating peroxymonosulfate(PMS)in Fenton-like catalysis.However,the conventional T_(d)-octahedral(Oh)connectivity in spinel structures restricts internal electron transfer,limiting the regeneration of low-valent metals and creating a trade-off between catalytic activity and long-term stability.Herein,we address this challenge by engineering a novel T_(d)-T_(d) connectivity in amorphous CoFeO_(x) nanosheets(a-CoFeO_(x) NSs).Soft X-ray absorption spectroscopy(sXAS)measurements reveal that in a-CoFeO_(x) nanosheets,the ligand field symmetry around Co atoms is dominated by a T_(d) coordination,in contrast to the O_(h) coordination in the crystalline state,which introduces T_(d)-T_(d) connection.Density functional theory(DFT)calculations confirm that the T_(d)-T_(d) connection in a-CoFeO_(x) structure significantly strengthens electron transfer to activate PMS,which exhibited a first-order kinetic constant(k_(obs))of 0.27 min^(-1) for sulfamethoxazole(SMX)removal with high stability.This study reveals that the phase-engineered CUS can further enhance catalytic activity and provides a simple and scalable strategy for optimizing spinel-type catalysts. 展开更多
关键词 spinel oxide amorphous phase engineering coordinatively unsaturated metal sites Fenton-like catalysis
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基于CA_MobileViT模型的水稻钾素营养诊断研究 被引量:1
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作者 吴正 杨红云 +2 位作者 孙爱珍 孔杰 黄淑梅 《中国农业科技导报(中英文)》 北大核心 2025年第8期80-88,共9页
为快速、准确地诊断水稻钾素的胁迫程度,以晚稻品种黄华占为材料进行大田试验,对基肥和拔节期追肥分别设置4个钾素施肥水平处理。以分蘖期和拔节期水稻主茎顶部3片展开叶的扫描图像作为数据集,以MobileViT为骨架,将Coordinate Attentio... 为快速、准确地诊断水稻钾素的胁迫程度,以晚稻品种黄华占为材料进行大田试验,对基肥和拔节期追肥分别设置4个钾素施肥水平处理。以分蘖期和拔节期水稻主茎顶部3片展开叶的扫描图像作为数据集,以MobileViT为骨架,将Coordinate Attention引入到MobileViT的Layer中的每个3×3卷积的BN层之后,构建CA_MobileViT模型并引入迁移学习。通过对比EfficientNet-V2、ConvNeXt、MobileViT和CA_MobileViT模型进行验证,结果表明:4个模型的准确率分别为98.4%、98.5%、94.2%、95.3%。其中CA_MobileViT模型的准确率为95.3%,比MobileViT模型提高了1.1百分点,却比EfficientNet-V2模型准确率低3.1百分点,比ConvNeXt模型准确率低3.2百分点,但CA_MobileViT模型参数量约EfficientNet-V2和ConvNeXt大模型的1/4,训练时间缩短了约1/3。改进的CA_MobileViT模型对于水稻钾素胁迫程度诊断具有较高的准确率,能有效地指导水稻钾素科学追肥管理,也为其他农作物的营养快速、精确诊断提供了一种普适、可行的方法。 展开更多
关键词 水稻 钾素营养诊断 轻量混合模型 迁移学习 Coordinate Attention
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Constructing a stable cobalt-nitrogen-carbon air cathode from coordinatively unsaturated zeolitic-imidazole frameworks for rechargeable zinc-air batteries 被引量:2
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作者 Tingting Wang Meng Liu +6 位作者 Somboon Chaemchuen Jichao Wang Ye Yuan Cheng Chen Ang Qiao Francis Verpoort Zongkui Kou 《Nano Research》 SCIE EI CSCD 2022年第7期5895-5901,共7页
Zeolitic-imidazole frameworks(ZIFs)derivations have widely emerged as an efficient air cathode of zinc-air batteries(ZABs)due to excellent bifunctional oxygen electrocatalysis performance.However,they are not stable e... Zeolitic-imidazole frameworks(ZIFs)derivations have widely emerged as an efficient air cathode of zinc-air batteries(ZABs)due to excellent bifunctional oxygen electrocatalysis performance.However,they are not stable enough for long-term operation of rechargeable ZABs because of weak association with current collector,especially under bending conditions for flexible ZAB devices.Here,we show that by purposely designing coordinatively unsaturated ZIFs via a facile morphology regulation,which can be chemically linked on acid-treated carbon cloth,a stable Co-N-C air cathode is therefore derived where Co nanoparticles(NPs)are uniformly confined within the Co-N-C matrix on carbon cloth(Co/Co-N-C/CC).Specifically,when without being stabilized from carbon cloth,the pyrolysis of ZIFs with different unsaturated coordination levels has a negligible impact on the bifunctional oxygen-catalyzed performance.The optimal Co/Co-N-C/CC catalyst assembled ZAB possesses a large open circuit voltage of 1.415 V and a high peak power density of 163 mW·cm^(−2) as well as excellent cycling durability upon 630 discharge–charge cycles with 61%voltage efficiency remained,largely exceeding those of a benchmark Pt/C-IrO_(2) catalyst assembled ZAB.The synergy between Co NPs and active Co-N-C sites via electronic interaction induces the outstanding bifunctional oxygen-catalyzed activity and cathode performance.The present work highlights the importance of unsaturated coordination structures in ZIFs precursors for the performance of derived nanostructures in integrated electrodes. 展开更多
关键词 coordinatively unsaturated zeolitic-imidazole frameworks(ZIFs) cobalt-nitrogen-carbon bifunctional air electrodes zincair battery flexible electrode
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Coupling and Spatial Disparities of Regional Economy and Ecosystem in High-Quality Town Development 被引量:2
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作者 Xinyi Ren Xiaowen Tan +2 位作者 Dan Luo Rongxin Lu Chien-Chi Chu 《Research in Ecology》 2025年第1期15-29,共15页
This study investigates the coordination between regional economic growth and ecological sustainability within the context of high-quality town economy development.To address the challenges of balancing economic expan... This study investigates the coordination between regional economic growth and ecological sustainability within the context of high-quality town economy development.To address the challenges of balancing economic expansion with environmental protection,a comprehensive evaluation index system is constructed,encompassing two key dimensions:regional economy and ecological environment.Using panel data from 2013 to 2022,the coupling coordination degree model is employed to quantify the interactions and synergy between these dimensions.Additionally,spatial econometric methods are applied to calculate both global and local Moran’s Index,revealing spatial clustering patterns,regional disparities,and heterogeneity.The relative development model further identifies critical factors influencing regional coordination,with a focus on the lagging development of basic infrastructure and public services.The findings demonstrate a positive temporal trend toward improved regional coordination and reduced development gaps,with a spatial pattern characterized by higher coupling degrees in eastern and central regions compared to western areas.Based on these results,this study proposes actionable strategies to enhance coordinated development,emphasizing ecological conservation,the establishment of green production and consumption systems,ecological restoration,and strengthened municipal collaboration.This revised abstract emphasizes the study’s purpose,methods,and key findings more clearly while maintaining a professional and concise tone.Finally,based on the above analysis results,the corresponding coordinated development suggestions of regional economy and ecological environment are given from the aspects of ecological environment protection measures,green production and consumption system construction,ecological environment restoration and municipal coordination. 展开更多
关键词 Regional Economies Ecological Environment Coupling Coordination Degree Spatiotemporal Distribution Characteristics Relative Development Model
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Learning Based Interference Coordination for Maritime Communications 被引量:1
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作者 Liu Chuhuan Xiao Liang +3 位作者 Chen Yifan Li Siyao Yang Helin Lyu Zefang 《China Communications》 2025年第4期356-374,共19页
With the boom in maritime activities,the need for highly reliable maritime communication is becoming urgent,which is an important component of 5G/6G communication networks.However,the bandwidth reuse characteristic of... With the boom in maritime activities,the need for highly reliable maritime communication is becoming urgent,which is an important component of 5G/6G communication networks.However,the bandwidth reuse characteristic of 5G/6G networks will inevitably lead to severe interference,resulting in degradation in the communication performance of maritime users.In this paper,we propose a safe deep reinforcement learning based interference coordination scheme to jointly optimize the power control and bandwidth allocation in maritime communication systems,and exploit the quality-of-service requirements of users as the risk value references to evaluate the communication policies.In particular,this scheme designs a deep neural network to select the communication policies through the evaluation network and update the parameters using the target network,which improves the communication performance and speeds up the convergence rate.Moreover,the Nash equilibrium of the interference coordination game and the computational complexity of the proposed scheme are analyzed.Simulation and experimental results verify the performance gain of the proposed scheme compared with benchmarks. 展开更多
关键词 bandwidth allocation interference coordination maritime communication power control rein-forcement learning
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Value Assessment Method for the Grid-Alternative Energy Storage Based on Coordinated Planning Framework 被引量:1
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作者 Bingqing Wu Yunli Yue +5 位作者 Yi Zhou Hengyu Zhou Haowen Guan Zhenjiang Shi Zili Chen Zhaoyuan Wu 《Energy Engineering》 2025年第2期621-649,共29页
As the development of new power systems accelerates and the impacts of high renewable energy integration and extreme weather intensify,grid-alternative energy storage is garnering increasing attention for its grid-int... As the development of new power systems accelerates and the impacts of high renewable energy integration and extreme weather intensify,grid-alternative energy storage is garnering increasing attention for its grid-interaction benefits and clear business models.Consequently,assessing the value of grid-alternative energy storage in the systemtransition has become critically important.Considering the performance characteristics of storage,we propose a value assessment frame-work for grid-alternative energy storage,quantifying its non-wires-alternative effects from both cost and benefit perspectives.Building on this,we developed a collaborative planning model for energy storage and transmission grids,aimed at maximizing the economic benefits of storage systems while balancing investment and operational costs.The model considers regional grid interconnections and their interactions with system operation.By participating in system operations,grid-alternative energy storage not only maximizes its own economic benefits but also generates social welfare transfer effects.Furthermore,based on multi-regional interconnected planning,grid-alternative energy storage can reduce system costs by approximately 35%,with the most significant changes observed in generation costs.Multi-regional coordinated planning significantly enhances the sys-tem’s flexibility in regulation.However,when the load factor of interconnection lines between regions remains constant,system operational flexibility tends to decrease,leading to a roughly 28.9%increase in storage investment.Additionally,under regional coordinated planning,the greater the disparity in wind power integration across interconnected regions,the more noticeable the reduction in system costs. 展开更多
关键词 Coordinated planning grid-alternative energy storage non-wires alternative effects value assessment
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Coupling Coordination Development and Driving Factors of New Energy Vehicles and Ecological Environment in China 被引量:1
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作者 XU Zonghuang 《Wuhan University Journal of Natural Sciences》 2025年第1期79-90,共12页
Studying the coupling coordination development of new energy vehicles(NEVs)and the ecological environment in China is helpful in promoting the development of NEVs in the country and is of great significance in promoti... Studying the coupling coordination development of new energy vehicles(NEVs)and the ecological environment in China is helpful in promoting the development of NEVs in the country and is of great significance in promoting high-quality development of new energy in China.This paper constructs an evaluation index system for the development of NEVs and the ecological environment.It uses game theory combining weighting model,particle swarm optimized projection tracking evaluation model,coupling coordination degree model,and machine learning algorithms to calculate and analyze the level of coupling coordination development of NEVs and the ecological environment in China from 2010 to 2021,and identifies the driving factors.The research results show that:(i)From 2010 to 2021,the development index of NEVs in China has steadily increased from 0.085 to 0.634,while the ecological environment level index significantly rose from 0.170 to 0.884,reflecting the continuous development of China in both NEVs and the ecological environment.(ii)From 2010 to 2012,the two systems—new energy vehicle(NEV)development and the ecological environment—were in a period of imbalance and decline.From 2013 to 2016,they underwent a transition period,and from 2017 to 2021,they entered a period of coordinated development showing a trend of benign and continuous improvement.By 2021,they reached a good level of coordination.(iii)Indicators such as the number of patents granted for NEVs,water consumption per unit of GDP,and energy consumption per unit of GDP are the main driving factors affecting the coupling coordination development of NEVs and the ecological environment in China. 展开更多
关键词 new energy vehicles(NEVs) ecological environment coupling coordination development machine learning driving factors
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Polyphenol-metal coordination derived high-entropy alloy as bifunctional oxygen electrocatalyst for Zn-air batteries 被引量:1
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作者 Meng-Di Hao Qin Li +3 位作者 Jing-Han Sun Deng Liu Hua-Long Yu Rui Liu 《Rare Metals》 2025年第4期2836-2844,共9页
High-entropy alloy(HEA)nanoparticles(NPs)have attracted great attention in electrocatalysis due to their tailorable complex compositions and unique properties.Herein,we introduce Fe,Co,Ni,Cr and Mn into the metal-poly... High-entropy alloy(HEA)nanoparticles(NPs)have attracted great attention in electrocatalysis due to their tailorable complex compositions and unique properties.Herein,we introduce Fe,Co,Ni,Cr and Mn into the metal-polyphenol coordination system to prepare HEA NPs enclosed in N-doped carbon(FeCoNiCrMn)with great potential for catalyzing oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).The unique high-entropy structural characteristics in FeCoNiCrMn facilitate effective interplay between metal species,leading to improved ORR(E_(1/2)=0.89 V)and OER(η=330 mV,j=10 mA·cm^(−2))activity.Additionally,FeCoNiCrMn exhibits excellent open-circuit voltage(1.523 V),power density(110 mW·cm^(−2))and long-term durability,outperforming Pt/C+IrO_(2) electrodes as a cathode catalyst in Zn-air batteries(ZABs).Such polyphenol-assisted alloying method broadens and simplifies the development of HEA electrocatalysts for high-performance ZABs. 展开更多
关键词 oxygen reduction reaction zinc air batteries metal sp bifunctional oxygen electrocatalyst oxygen evolution reaction oer nanoparticles polyphenol metal coordination hea nps
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DCA-YOLO:Detection Algorithm for YOLOv8 Pulmonary Nodules Based on Attention Mechanism Optimization 被引量:1
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作者 SONG Yongsheng LIU Guohua 《Journal of Donghua University(English Edition)》 2025年第1期78-87,共10页
Pulmonary nodules represent an early manifestation of lung cancer.However,pulmonary nodules only constitute a small portion of the overall image,posing challenges for physicians in image interpretation and potentially... Pulmonary nodules represent an early manifestation of lung cancer.However,pulmonary nodules only constitute a small portion of the overall image,posing challenges for physicians in image interpretation and potentially leading to false positives or missed detections.To solve these problems,the YOLOv8 network is enhanced by adding deformable convolution and atrous spatial pyramid pooling(ASPP),along with the integration of a coordinate attention(CA)mechanism.This allows the network to focus on small targets while expanding the receptive field without losing resolution.At the same time,context information on the target is gathered and feature expression is enhanced by attention modules in different directions.It effectively improves the positioning accuracy and achieves good results on the LUNA16 dataset.Compared with other detection algorithms,it improves the accuracy of pulmonary nodule detection to a certain extent. 展开更多
关键词 pulmonary nodule YOLOv8 network object detection deformable convolution atrous spatial pyramid pooling(ASPP) coordinate attention(CA)mechanism
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Fabrication of RDX Based Composites via Water Flotation and Monometallic Polydopamine Coatings
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作者 LI Xiao QIN Liang +5 位作者 XU Jian-xin ZHANG Lu-yao SHEN Jin-jie LAN Guan-chao WANG Jian-long CHEN Li-zhen 《火炸药学报》 北大核心 2025年第8期763-769,I0004,共8页
To enhance the overall performance of cyclotrimethylenetrinitramine(RDX),a modification strategy for RDX via in situ coordination with monometallic polydopamine(PDA)coatings(PDA-Fe,PDA-Cu,and PDA-Pb)was developed.The ... To enhance the overall performance of cyclotrimethylenetrinitramine(RDX),a modification strategy for RDX via in situ coordination with monometallic polydopamine(PDA)coatings(PDA-Fe,PDA-Cu,and PDA-Pb)was developed.The thermal properties of pristine RDX and its modified variants(RDX@PDA-Fe,RDX@PDA-Cu,RDX@PDA-Pb)were characterized using differential scanning calorimetry(DSC)and accelerating rate calorimetry(ARC).The impact sensitivity of these materials was evaluated via the characteristic drop-height method.The results demonstrate that PDA-metal metal coatings—formed through coordination between PDA and single metal ions(Fe^(3+),Cu^(2+),or Pb^(2+))—significantly enhance RDX′s thermal stability while attenuating its mechanical sensitivity.These coatings act as energy-absorbing barriers against external stimuli,effectively mitigating RDX′s sensitivity.Furthermore,they elevate RDX′s thermal stability by increasing its decomposition onset temperature and accelerating its decomposition kinetics.The monometallic coatings also catalyze RDX′s thermal decomposition and combustion,with Cu and Pb exhibiting particularly distinct catalytic effects. 展开更多
关键词 physical chemistry RDX situ coordination COMPOSITES catalytic mechanic
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A viologen-based Cd(Ⅱ)coordination polymer:Self-assembly,thermochromism,and electrochemical property
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作者 LI Xiaonan HAN Hui +3 位作者 ZHANG Yihan XIONG Jing GUO Tingting YAN Juanzhi 《无机化学学报》 北大核心 2025年第7期1439-1444,共6页
Under the condition of solvothermal synthesis,the viologen ligand 1,1′-bis(3-carboxyphenyl)-(4,4′-bipyri-dine)dichloride(H_(2)bcbpy·2Cl)and KI are coordinated with the metal cadmium ions.A case of thermochromic... Under the condition of solvothermal synthesis,the viologen ligand 1,1′-bis(3-carboxyphenyl)-(4,4′-bipyri-dine)dichloride(H_(2)bcbpy·2Cl)and KI are coordinated with the metal cadmium ions.A case of thermochromic coor-dination polymer[Cd(bcbpy)I_(2)]·2H_(2)O(1)was constructed.Complex 1 displays a 1D chain structure and exhibits thermochromic behavior.Under different temperature stimulation,the complex(ground)slowly changed from green to yellow-green,and with the increase of temperature,the color of complex 1 gradually deepened,and finally became orange-yellow.Therefore,complex 1 was prepared as a thermochromic film.In addition,we also performed electrochemical tests on complex 1,which showed that the complex is a semiconductor material.CCDC:2391802. 展开更多
关键词 coordination polymer VIOLOGEN THERMOCHROMISM electrochemical property
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Coordination polymers based on anthracene-and pyrene-derived ligands:Crystal structure,fluorescent property,and framework isomerization
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作者 HU Youbo LI Donggang +2 位作者 SUN Changhua LU Zhenzhong GU Songjun 《无机化学学报》 北大核心 2025年第8期1681-1688,共8页
Six coordination polymers based on 9,10-di(pyridine-4-yl)-anthracene(DPA)and 1,6-di(1H-imidazol-1-yl)pyrene(DIP)were obtained by solvothermal reactions.{[Zn(DPA)Cl_(2)]·DMF·2H_(2)O}n(1)and{[Zn_(1.5)(DPA)_(1.... Six coordination polymers based on 9,10-di(pyridine-4-yl)-anthracene(DPA)and 1,6-di(1H-imidazol-1-yl)pyrene(DIP)were obtained by solvothermal reactions.{[Zn(DPA)Cl_(2)]·DMF·2H_(2)O}n(1)and{[Zn_(1.5)(DPA)_(1.5)Cl_(3)]·5H_(2)O}n(2)are framework isomers,which both contain zigzag chains formed by DPA,Zn^(2+),and Cl-.The zigzag chains in 1 are further assembled by C—H…Cl interactions into layers,and these layers exhibit two different orientations,displaying a rare 2D to 3D interpenetration mode.The zigzag chains in 2 are parallelly arranged.{[Zn_(3)(DPA)_(3)Br_(6)]·2DMF·_(1.5)H_(2)O}n(3)is isostructural to 2.3 was obtained using ZnBr_(2)instead of ZnCl_(2).[M(DPA)(formate)_(2)(H_(2)O)_(2)]n[M=Co(4),Cu(5)]are isostructural,contain chain structures formed by DPA,Cu^(2+)/Co^(2+),and for-mate ions,which were formed in situ in the solvothermal reaction.{[Zn(DIP)_(2)Cl]ClO_(4)}n(6)contains a layer structure formed by DIP and Zn^(2+).Free DPA and DIP ligands exhibited high fluorescence at room temperature,and coordina-tion polymers 3 and 6 displayed enhanced fluorescent emissions. 展开更多
关键词 coordination polymer anthracene derivatives pyrene derivatives fluorescence framework isomerization
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Structure and magnetic properties of Mn(Ⅱ)coordination polymers regulated by N-auxiliary ligands
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作者 LIU Xiaxia MA Xiaofang +2 位作者 GUO Luxia HAN Xianda FENG Sisi 《无机化学学报》 北大核心 2025年第3期587-596,共10页
Two new Mn(Ⅱ)coordination polymers,namely{[Mn_(2)(HL)(phen)_(3)(H_(2)O)_(2)]·7.5H_(2)O}_n(1)and[Mn_(4)(HL)_(2)(1,4-bib)_(3)(H_(2)O)_(2)]_n(2),were synthesized under hydrothermal conditions by using Mn(Ⅱ)ions an... Two new Mn(Ⅱ)coordination polymers,namely{[Mn_(2)(HL)(phen)_(3)(H_(2)O)_(2)]·7.5H_(2)O}_n(1)and[Mn_(4)(HL)_(2)(1,4-bib)_(3)(H_(2)O)_(2)]_n(2),were synthesized under hydrothermal conditions by using Mn(Ⅱ)ions and 6-(3',4'-dicarboxylphenoxy)-1,2,4-benzenetricarboxylic acid(H_(5)L)in the presence of N-auxiliary ligands 1,10-phenanthroline(phen)and1,4-bis(1H-imidazol-1-yl)benzene(1,4-bib).The structures of coordination polymers 1 and 2 were characterized by infrared spectroscopy,single-crystal X-ray diffraction,thermogravimetric analysis,and powder X-ray diffraction.Single-crystal X-ray diffraction reveals that 1 has a 1D chain structure based on binuclear Mn(Ⅱ)units,while 2 features a(3,8)-connected 3D network structure based on tetranuclear Mn(Ⅱ)units.Magnetic studies show that 1 and 2exhibit antiferromagnetic interactions between manganese ions.2 shows stronger antiferromagnetic interactions due to the shorter Mn…Mn distances within the tetranuclear manganese units.CCDC:2357601,1;2357602,2. 展开更多
关键词 coordination polymers crystal structures binuclear Mnunit tetranuclear Mnunit MAGNETISM
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Fluorescent coordination polymers based on anthracene-and pyrene-derivative ligands
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作者 XI Jiming TENG Yukang +1 位作者 ZHANG Rui LU Zhenzhong 《无机化学学报》 北大核心 2025年第5期847-854,共8页
We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),campho... We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),camphoric acid(H_(2)cpa)].In[Cd(dip)(cda)]·4H_(2)O}_(n)(1),the Cd^(2+)ions,acting as tetrahedral nodes,are linked by dipand cda^(2-)ligands with four Cd^(2+)ions into five-fold interpenetrating network array of topology of dia.In{[Cd(dip)(cpa)]·4H_(2)O}_(n)(2),the Cd^(2+)ions,acting as a 4-connector,are linked by cpa^(2-)and dip ligands into a 3D framework ofcds topology.In{[Ni(dia)_(2)Cl_(2)]·DMF}_(n)(3),the Ni^(2+)ion is linked by four dia ligands into a layer structure,and 1Dchannels of a cross-section of 1.35 nm×0.96 nm are formed.In{[Cd(dia)_(2)(H_(2)O)_(2)](NO_(3))_(2)·2DMSO}n(4),the dia ligandsconnected Cd^(2+)ions into a 2D layer,and 1D channels are formed between adjacent layers with a cross-section of0.87 nm×0.43 nm.In[Zn(dip)Cl_(2)]_(n)(5),the Zn^(2+)ion is linked by dip ligands into an infinite 1D chain.The infrared,thermal gravimetric,and fluorescent emission data were collected and analyzed for these coordination polymers.CCDC:2356055,1;2440075,2;2356057,3;2356057,4;2356059,5. 展开更多
关键词 coordination polymer anthracene derivatives pyrene derivatives FLUORESCENCE
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Syntheses,characterization,and luminescence properties of Yb(Ⅲ)-based one-dimensional chain coordination polymer
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作者 CHEN Wanting MIAO Chufei +4 位作者 LIU Yan ZHENG Bobi ZHENG Xiaoyu XU Han TIAN Jumei 《无机化学学报》 北大核心 2025年第8期1672-1680,共9页
One Yb(Ⅲ)-based coordination polymer,{[Yb(H_(2)dhtp)1.5(H_(2)O)_(4)]·3H_(2)O}n(1)(H_(4)dhtp=2,5-dihydroxytere-phthalic acid),was fabricated and structurally characterized by single-crystal X-ray diffraction,IR,p... One Yb(Ⅲ)-based coordination polymer,{[Yb(H_(2)dhtp)1.5(H_(2)O)_(4)]·3H_(2)O}n(1)(H_(4)dhtp=2,5-dihydroxytere-phthalic acid),was fabricated and structurally characterized by single-crystal X-ray diffraction,IR,powder X-ray diffraction,X-ray diffraction,and elemental analysis.Complex 1 displays a 1D chain structure,and belongs to P1 group.The solid-state luminescent spectrum of 1 showed an emission band with the maximum at 508 nm(λex=408 nm).It exhibited the emission characteristic of the H_(4)dhtp ligand.The fluorescence of 1 in water displayed the stron-gest intensity.In detecting various metal ions,adding Zr^(4+)led to a blue shift in fluorescence,accompanied by an increase in intensity,whereas the presence of Fe^(3+)resulted in a decrease in luminescence.The changes observed in the IR spectrum indicate an interaction between Fe^(3+)/Zr^(4+)and complex 1,resulting in the variation of luminescence properties. 展开更多
关键词 coordination polymers STRUCTURE LUMINESCENCE
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High-performance supercapacitor based on 1D cobalt-based coordination polymer
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作者 RONG Hongren GAO Gexiang +5 位作者 LIU Zhiwei ZHOU Ke SU Lixin HUANG Hao LIU Wenlong LIU Qi 《无机化学学报》 北大核心 2025年第6期1183-1195,共13页
A low-cost 1D cobalt-based coordination polymer(CP)[Co(BGPD)(DMSO)_(2)(H_(2)O)_(2)](Co-BD;H2BGPD=N,N'-bis(glycinyl)pyromellitic diimide;DMSO=dimethyl sulfoxide)was synthesized by a simple method,and its crystal st... A low-cost 1D cobalt-based coordination polymer(CP)[Co(BGPD)(DMSO)_(2)(H_(2)O)_(2)](Co-BD;H2BGPD=N,N'-bis(glycinyl)pyromellitic diimide;DMSO=dimethyl sulfoxide)was synthesized by a simple method,and its crystal structure was characterized.In a three-electrode system,Co-BD,as the electrode material for supercapacitors,achieved a specific capacitance of 830 F·g^(-1)at 1 A·g^(-1),equivalent to a specific capacity of 116.4 mAh·g^(-1),and exhibited high-rate capability,reaching 212 F·g^(-1)at 20 A·g^(-1).Impressively,Co-BD||rGO(reduced graphene oxide),representing an asymmetrical supercapacitor,owns a higher energy density of 14.2 Wh·kg^(-1)at 0.80 kW·kg^(-1),and an excellent cycle performance(After 4000 cycles at 1 A·g^(-1),the capacitance retention was up to 94%).CCDC:2418872. 展开更多
关键词 SUPERCAPACITOR cobalt compound coordination polymers crystal structure electrode materials electrochemical performances
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A cadmium(Ⅱ)coordination polymer based on a semirigid tetracarboxylate ligand for highly selective detection of Fe^(3+)and 4-nitrophenol
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作者 BAI Yu WANG Jijiang +4 位作者 TANG Long YUE Erlin BAI Chao WANG Xiao ZHANG Yuqi 《无机化学学报》 北大核心 2025年第6期1217-1226,共10页
A novel coordination polymer(CP){[Cd_(2)(L)(1,4-bimb)_(1.5)(DMF)_(2)]·DMF}n(1)(H_(4)L=5,5'-[1,1'-biphenyl-4,4'-diylbis(oxy)]diisophthalic acid,1,4-bimb=1,4-bis(imidazole-1-ylmethyl)-benzene)has been d... A novel coordination polymer(CP){[Cd_(2)(L)(1,4-bimb)_(1.5)(DMF)_(2)]·DMF}n(1)(H_(4)L=5,5'-[1,1'-biphenyl-4,4'-diylbis(oxy)]diisophthalic acid,1,4-bimb=1,4-bis(imidazole-1-ylmethyl)-benzene)has been designed and synthesized through solvothermal reaction.Structural analysis shows that Cd(Ⅱ)is connected by H4L and 1,4-bimb to form a 2D network,and 1,4-bimb further expands the 2D network into a 3D framework.CP 1 can be used as an excellent fluorescence sensor for Fe^(3+)and 4-nitrophenol(4-NP),with low detection limits and good anti-interference.The detection limits of Fe^(3+)and 4-NP were 0.034 and 0.031μmol·L^(-1),respectively.In addition,the fluorescence quenching mechanism was studied.1 was successfully applied to determine Fe^(3+)and 4-NP content in the Yanhe River water sample.CCDC:2351092. 展开更多
关键词 coordination polymer Fe^(3+) 4-NITROPHENOL fluorescence sensing
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