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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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Altering peroxymonosulfate activation path for^(1)O_(2)production on ZIF-67 with coordinatively unsaturated metal sites
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作者 Hongyan Liu Wanting Hui +8 位作者 Heyu Gao Guangjie Qu Wenwen Lv Xu Guo Zixin Li Bingbing Li Maoquan Wu Tongjie Yao Jie Wu 《Frontiers of Environmental Science & Engineering》 2025年第11期237-251,共15页
In Fenton-like reaction activated by peroxymonosulfate(PMS),compared to SO_(4)^(•-)produced via the electron acceptance path,^(1)O_(2)generated from electron donation path were more attractive.Herein,PMS activation pa... In Fenton-like reaction activated by peroxymonosulfate(PMS),compared to SO_(4)^(•-)produced via the electron acceptance path,^(1)O_(2)generated from electron donation path were more attractive.Herein,PMS activation path was altered from SO_(4)^(•-)to^(1)O_(2)through improving Lewis acidity on catalytic sites.During ZIF-67 preparation,vanillin(VAN)was introduced to regulate the chemical environment around the Co^(3+/2+)nodes.The coordinated N atoms in 2-methylimidazole were partially substituted by O atoms in VAN,leading to the enhanced Lewis acidity on Co^(3+/2+)sites.In this case,Lewis base PMS were likely to donate electrons to electron-deficient Co^(3+/2+)sites,and 1O_(2)were generated as the primary radicals.Besides,coordinatively unsaturated metal sites(CUMSs)were produced during the substitution process,since Co^(3+/2+)nodes were not fully bridged by VAN ligands.This improved the PMS utilization efficiency and ^(1)O_(2)yield.Previous studies have indicated the metal leaching would be worsened by CUMSs,owing to the lack of ligand protection.To solve this problem,a Co_(2)SiO_(4)shell was coated on VAN-ZIF-x surface.VAN-ZIF-x@Co_(2)SiO_(4)yolk@shell nanoreactor not only suppressed the metal leaching,but also improved the environmental adaption.This paper gave a novel insight on altering the PMS activation path,together with the CUMSs creation on catalyst surface. 展开更多
关键词 Fenton-like reaction VANILLIN Yolk@shell nanoreactor coordinatively unstaurated metal sites PMS utilization efficiency
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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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基于改进YOLOv5的砖石建筑裂缝检测方法
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作者 翁文杏 余兆钗 +2 位作者 李佐勇 李炜 吴景岚 《计算机应用与软件》 北大核心 2026年第2期189-196,222,共9页
砖石建筑极易出现裂缝,严重威胁建筑寿命和人民生命财产安全,因此,裂缝检测是建筑维护的重要基础。为了提升砖石建筑裂缝的检测精度,应用YOLOv5s的改进方法。将SPD-Conv引入到骨干网络中,提高细粒度特征的检测能力;使用BiFPN并结合Coord... 砖石建筑极易出现裂缝,严重威胁建筑寿命和人民生命财产安全,因此,裂缝检测是建筑维护的重要基础。为了提升砖石建筑裂缝的检测精度,应用YOLOv5s的改进方法。将SPD-Conv引入到骨干网络中,提高细粒度特征的检测能力;使用BiFPN并结合Coordinate Attention模块来代替YOLOv5的特征融合网络,提升检测精度;使用SIoU Loss来代替原有损失函数,改善在复杂环境下检测不佳的情况。在砖石建筑裂缝数据集上的实验结果表明,所提方法的平均均值精度(mAP@0.5)达到96.0%,比原YOLOv5s提高了4.0百分点,比2023年提出的YOLOv8s提高了2.0百分点,可以有效地检测砖石建筑裂缝。 展开更多
关键词 砖石建筑 裂缝检测 YOLOv5 SPD-Conv BiFPN Coordinate Attention SIoU Loss
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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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Syntheses and fluorescent sensing properties of two coordination polymers based on 9,9′‑dihexyl‑2,7‑di(pyridin‑4‑yl)fluorene
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作者 WANG Gaofeng SUN Shuwen +1 位作者 Meng Lixin PENG Dequn 《无机化学学报》 北大核心 2026年第2期331-339,共9页
Under solvothermal conditions,1,4‑naphthalenedicarboxylic acid(H_(2)ndc)and 9,9′‑dihexyl‑2,7‑di(pyridin‑4‑yl)fluorene(hfdp)reacted with Co^(2+)ions and Cd^(2+)ions to form two coordination polymers,[Co(hfdp)(ndc)(H2O... Under solvothermal conditions,1,4‑naphthalenedicarboxylic acid(H_(2)ndc)and 9,9′‑dihexyl‑2,7‑di(pyridin‑4‑yl)fluorene(hfdp)reacted with Co^(2+)ions and Cd^(2+)ions to form two coordination polymers,[Co(hfdp)(ndc)(H2O)]·DMA}n(1)and{[Cd(hfdp)(ndc)(H_(2)O)]·DMA}_(n)(2),respectively(DMA=N,N‑dimethylacetamide).Single‑crystal X‑ray diffraction analyses showed that both complexes 1 and 2 contain similar structures.Topological analysis indicates that complexes 1 and 2 have a{44·62}planar structure.In addition,both complexes reveal good thermal stability and fluorescence sensing performance.They exhibited good sensitivity and selectivity towards 2,4,6‑trinitrophenol(TNP)by fluorescent quenching.The limits of detection of 1 and 2 for TNP were 0.107 and 0.327μmol·L^(-1),respectively.CCDC:2475515,1;2475516,2. 展开更多
关键词 coordination polymers cadmium(Ⅱ) TOPOLOGY FLUORESCENCE FLUORENE
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Synthesis and crystal structures of Co(Ⅱ)/Cu(Ⅱ)coordination polymers based on solvent and ligand concentration regulation strategy
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作者 SUN Yinxia LIU Liping +7 位作者 BAI Xue SUN Yu SUN Wanhong DENG Zhepeng CHEN Jianghai WANG Jianjun XU Li ZHANG Shuzhen 《无机化学学报》 北大核心 2026年第2期340-354,共15页
Four distinct coordination polymers(CPs)were successfully synthesized by altering solvent types and adjusting ligand concentrations,and their crystal structures were investigated.[Co(L)(FDCA)(H_(2)O)_(2)]·0.5H_(2... Four distinct coordination polymers(CPs)were successfully synthesized by altering solvent types and adjusting ligand concentrations,and their crystal structures were investigated.[Co(L)(FDCA)(H_(2)O)_(2)]·0.5H_(2)O(1)was synthesized as a 2D structure using Coas the metal source,methanol‑water(4∶6,V/V)as the solvent,and specific concentrations of 2,5‑furandicarboxylic acid(H_(2)FDCA)and 1,3,5‑triimidazole benzene(L).Adjusting to pure water and lowering the concentration of L yielded the 1D chain structure of[Co(HL)2(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(2).Using Cu(Ⅱ)as the metal source,methanol/water(9∶1,V/V)as the solvent,and specific concentrations of L and H2FDCA,the 1D chain structure of[Cu(L)(FDCA)(H_(2)O)]·2H_(2)O(3)was synthesized.Upon increasing the concentrations of L and H2FDCA,and switching the solvent to pure water,the 1D chain structure of[Cu(HL)_(2)(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(4)was obtained.This shows that changing the solvent and ligand concentrations can affect the structural changes of CPs.In addition,the solid‑state photoluminescence of CPs 1‑4 at room temperature was studied,and their morphological changes were observed via scanning electron microscopy.Density functional theory calculations revealed that the negative charge concentrates on the O and N atoms of the ligand,facilitating ligand‑metal ion coordination.CCDC:2403934,1;2403935,2;2403936,3;2403938,4. 展开更多
关键词 Co(Ⅱ)/Cu(Ⅱ)coordination polymer crystal structure solvent system ligand concentration regulation strategy
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Coordinated Source-Network-Storage Inertia Control Strategy Based on Wind Power Transmission via MMC-HVDC System
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作者 Mengxuan Shi Lintao Li +3 位作者 Dejun Shao Xiaojie Pan Xingyu Shi Yuxun Wang 《Energy Engineering》 2026年第1期493-510,共18页
In wind power transmission via modular multilevel converter based high voltage direct current(MMCHVDC)systems,under traditional control strategies,MMC-HVDCcannot provide inertia support to the receiving-end grid(REG)d... In wind power transmission via modular multilevel converter based high voltage direct current(MMCHVDC)systems,under traditional control strategies,MMC-HVDCcannot provide inertia support to the receiving-end grid(REG)during disturbances.Moreover,due to the frequency decoupling between the two ends of the MMCHVDC,the sending-end wind farm(SEWF)cannot obtain the frequency variation information of the REG to provide inertia response.Therefore,this paper proposes a novel coordinated source-network-storage inertia control strategy based on wind power transmission via MMC-HVDC system.First,the grid-side MMC station(GS-MMC)maps the frequency variations of the REG to direct current(DC)voltage variations through the frequency mapping control,and uses submodule capacitor energy to provide inertial power.Then,the wind farm-side MMC station(WF-MMC)restores the DC voltage variations to frequency variations through the frequency restoration control and power loss compensation,providing real-time frequency information for the wind farm.Finally,based on real-time frequency information,thewind farmutilizes the rotor kinetic energy and energy storage to provide fast and lasting power support through the wind-storage coordinated inertia control strategy.Meanwhile,when the wind turbines withdraw from the inertia response phase,the energy storage can increase the power output to compensate for the power deficit,preventing secondary frequency drops.Furthermore,this paper uses small-signal analysis to determine the appropriate values for the key parameters of the proposed control strategy.A simulation model of the wind power transmission via MMCHVDC system is built in MATLAB/Simulink environment to validate and evaluate the proposed method.The results show that the proposed coordinated control strategy can effectively improve the system inertia level and avoid the secondary frequency drop under the load sudden increase condition. 展开更多
关键词 Wind and storage coordination modular multilevel converter inertia response coordinated control
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Coordination-driven in-situ reduction and extraction of neptunium
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作者 Huaixin Hao Shuyun Zhang +7 位作者 Xue Dong Qilong Tang Yuxiao Guo Yaoyang Liu Jing Chen Jing Su Zhipeng Wang Chao Xu 《Science China Chemistry》 2026年第2期777-783,共7页
The recycling of neptunium(Np)from nuclear wastes is crucial for the sustainable development of nuclear energy,yet it is still a challenging task owing to the complexity of Np chemistry.Precise control of oxidation st... The recycling of neptunium(Np)from nuclear wastes is crucial for the sustainable development of nuclear energy,yet it is still a challenging task owing to the complexity of Np chemistry.Precise control of oxidation state is highly desirable for the effective recovery of Np.In this study,we report an innovative strategy for Np recovery through in-situ coordination and reduction of Np(Ⅴ)in a biphasic extraction system.By leveraging the synergistic effects of coordination by a P=O donating ligand(trialkyl phosphine oxide,TRPO)and reduction by hydroquinone(HQ)in the organic phase,efficient Np(Ⅴ)-to-Np(Ⅳ)conversion and high distribution ratio(D)of Np were achieved in a single extraction contact.The reduction mechanism of Np was elucidated through spectroscopic and theoretical analyses.This work enriches the redox chemistry of Np and provides a novel pathway for Np recovery in advanced nuclear fuel cycles. 展开更多
关键词 NEPTUNIUM COORDINATION REDUCTION EXTRACTION
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Extra-pineal melatonin in perisynaptic Schwann cell–muscle fiber cross talk at the regenerating neuromuscular junction
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作者 Samuele Negro Cesare Montecucco Michela Rigoni 《Neural Regeneration Research》 2026年第1期300-301,共2页
The neuromuscular junction and its proregenerative niche:The mammalian peripheral nervous system,unlike the central nervous system,has preserved throughout evolution the ability to regenerate and fully restore functio... The neuromuscular junction and its proregenerative niche:The mammalian peripheral nervous system,unlike the central nervous system,has preserved throughout evolution the ability to regenerate and fully restore function.Key factors for effective nerve regeneration include a supportive neuronal environment and a coordinated tissue response(Brosius Lutz and Barres,2014). 展开更多
关键词 FUNCTION SYSTEM COORDINATED
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A formation pursuit method integrated coordinated reciprocity for enhanced capture
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作者 XING Xiaoyu XIA Haoxiang 《Journal of Systems Engineering and Electronics》 2026年第1期211-224,共14页
Cooperative pursuit poses challenges across natural,social,and technical systems,particularly when decentralized,slow-speed pursuers attempt to capture a high-speed evader with limited observation.Most existing contri... Cooperative pursuit poses challenges across natural,social,and technical systems,particularly when decentralized,slow-speed pursuers attempt to capture a high-speed evader with limited observation.Most existing contributions place the focus on the greedy pursuit of the evader,overlooking potential collaborations among pursuers.To tackle this issue,a decisionmaking framework of multi-agent coordinated reciprocity formation pursuit(MACRFP)via deep reinforcement learning is introduced.This framework integrates the actor-critic algorithm with the coordinated reciprocity mechanism to enhance the capability of capturing a faster evader.Initially,a local perception model is created by utilizing a cellular network to simulate limitations caused by obstacles.Next,the formation coalition of pursuit is guided by the Cartesian Oval,enabling dispersed pursuers to create a siege against the faster evader.Furthermore,a coordinated reciprocity model based on the coordination graph and the attention-based graph neural networks is developed,addressing the global coordination problem by estimating a reciprocity coefficient to adjust agents'rewards.Numerical simulations demonstrate the emergence of cooperative behaviors in cooperative besiegement,target tracking,and intelligent interception during the pursuit,indicating that the proposed algorithm enhances the feasibility and effectiveness of capturing a fast-escaping target by integrating coordinated reciprocity and coalition formation. 展开更多
关键词 multi-agent system reinforcement learning cooperative pursuit coordinated reciprocity
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Oxophilic sites activate asymmetric IrNi atomic dimers and clusters for efficient hydrogen oxidation and CO tolerance
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作者 Mansheng Liao Fangjun Luo +9 位作者 Yuan Zhang Ruoyu Wei Zhongyao Zhang Ruiwen Qi Jun Yu Yongliang Li Xiangzhong Ren Lei Zhang Qianling Zhang Zhongxin Song 《Science China Materials》 2026年第3期1464-1474,共11页
Multi-site coupling is a promising strategy for developing highly efficient and CO-resistant hydrogen oxidation reaction(HOR)catalysts for proton exchange membrane fuel cells(PEMFCs).However,designing multifunctional ... Multi-site coupling is a promising strategy for developing highly efficient and CO-resistant hydrogen oxidation reaction(HOR)catalysts for proton exchange membrane fuel cells(PEMFCs).However,designing multifunctional synergistic schemes for single-atom sites remains a significant challenge.Herein,we propose a dual-template-confined oxophilic engineering strategy to construct well-dispersed iridium-nickel(IrNi)atomic dimers adjacent to IrNi nanoclusters on porous nitrogen-doped carbon(IrNi_(Dimer/NC1.8)-PNC).The paired IrNi dimer features an asymmetric Ir-N_(3)configuration coordinated with heteroatomic Ni-N_(3)O via an N-bridge.Remarkably,IrNi_(Dimer/NC1.8)-PNC exhibits a~23-fold enhancement in mass activity(4.36 A mg-1Ir at 20 mV)and 5-fold longer stability compared to benchmarking Pt/C toward HOR,while achieving a high rated power density of 1.18 W cm^(-2)in PEMFC anode applications.Furthermore,IrNi_(Dimer/NC1.8)-PNC demonstrates superior CO tolerance over monometallic Ir and Pt/C in both half-cell and full-cell devices.Combined experimental and density functional theory studies reveal that oxophilic Ni modulates the electronic environment of Ir through alloying and dimer interactions,thereby enhancing HOR activity.Importantly,the asymmetric IrNi dimer enables efficient CO^(*)and OH^(*)co-adsorption while facilitating CO_(2)^(*)desorption,synergistically mitigating CO poisoning and improving atom utilization efficiency.This work provides a design strategy and fundamental insights for multi-site synergistic catalysts in PEMFC anodes. 展开更多
关键词 IrNi dimer asymmetric coordination synergistic interaction hydrogen oxidation CO tolerance PEMFC
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Interventional Room Nursing for Patients with Ischemic Stroke Treated with Tirofiban Combined with Direct Thrombectomy
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作者 Yayun Xiong 《Journal of Clinical and Nursing Research》 2026年第1期214-220,共7页
Objective:To explore the interventional room nursing and its application effects in patients with ischemic stroke treated with tirofiban combined with direct thrombectomy.Methods:A total of 61 patients with ischemic s... Objective:To explore the interventional room nursing and its application effects in patients with ischemic stroke treated with tirofiban combined with direct thrombectomy.Methods:A total of 61 patients with ischemic stroke admitted to our hospital from June 2024 to June 2025 were selected and divided into two groups using the red and blue ball method:the control group(n=30,receiving routine interventional room nursing)and the observation group(n=31,receiving additional tirofiban medication-specific nursing+individualized interventional nursing on the basis of routine nursing).The cerebral hemodynamic indicators,adverse reactions,effectiveness of complication nursing,and nursing satisfaction were compared between the two groups.Results:After 7 days of treatment,the observation group had lower cerebrovascular peripheral resistance and higher mean blood flow velocity and mean blood flow volume compared to the control group(all p<0.05).The observation group had a higher effectiveness rate of complication nursing than the control group,with a statistically significant difference(p<0.05).The nursing satisfaction in the observation group(96.77%)was higher than that in the control group(80.00%),with a statistically significant difference(χ^(2)=4.223,p=0.040<0.05).Conclusion:Tirofiban combined with direct thrombectomy can significantly improve cerebral hemodynamics,enhance the effectiveness of complication nursing,and increase patient satisfaction in patients with ischemic stroke. 展开更多
关键词 Tirofiban Direct thrombectomy Ischemic stroke Interventional room nursing Nursing coordination
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Te-Modulated Fe Single Atom with Synergistic Bidirectional Catalysis for High-Rate and Long-Cycling Lithium-Sulfur Battery
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作者 Jian Guo Lu Chen +4 位作者 Lijun Wang Kangfei Liu Ting He Jia Yu Hongbin Zhao 《Nano-Micro Letters》 2026年第1期827-842,共16页
Single-atom catalysts(SACs)have garnered significant attention in lithium-sulfur(Li-S)batteries for their potential to mitigate the severe polysulfide shuttle effect and sluggish redox kinetics.However,the development... Single-atom catalysts(SACs)have garnered significant attention in lithium-sulfur(Li-S)batteries for their potential to mitigate the severe polysulfide shuttle effect and sluggish redox kinetics.However,the development of highly efficient SACs and a comprehensive understanding of their structure-activity relationships remain enormously challenging.Herein,a novel kind of Fe-based SAC featuring an asymmetric FeN_(5)-TeN_(4) coordination structure was precisely designed by introducing Te atom adjacent to the Fe active center to enhance the catalytic activity.Theoretical calculations reveal that the neighboring Te atom modulates the local coordination environment of the central Fe site,elevating the d-band center closer to the Fermi level and strengthening the d-p orbital hybridization between the catalyst and sulfur species,thereby immobilizing polysulfides and improving the bidirectional catalysis of Li-S redox.Consequently,the Fe-Te atom pair catalyst endows Li-S batteries with exceptional rate performance,achieving a high specific capacity of 735 mAh g^(−1) at 5 C,and remarkable cycling stability with a low decay rate of 0.038%per cycle over 1000 cycles at 1 C.This work provides fundamental insights into the electronic structure modulation of SACs and establishes a clear correlation between precisely engineered atomic configurations and their enhanced catalytic performance in Li-S electrochemistry. 展开更多
关键词 Single-atom catalyst Coordination environment Electronic structure Bidirectional catalysis Li-S batteries
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A Coordinated Multi-Loop Control Strategy for Fault Ride-Through in Grid-Forming Converters
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作者 Zhuang Liu Mingwei Ren +1 位作者 Kai Shi Peifeng Xu 《Energy Engineering》 2026年第1期115-135,共21页
Grid-Forming(GFM)converters are prone to fault-induced overcurrent and power angle instability during grid fault-induced voltage sags.To address this,this paper develops a multi-loop coordinated fault ridethrough(FRT)... Grid-Forming(GFM)converters are prone to fault-induced overcurrent and power angle instability during grid fault-induced voltage sags.To address this,this paper develops a multi-loop coordinated fault ridethrough(FRT)control strategy based on a power outer loop and voltage-current inner loops,aiming to enhance the stability and current-limiting capability of GFM converters during grid fault conditions.During voltage sags,the GFM converter’s voltage source behavior is maintained by dynamically adjusting the reactive power reference to provide voltage support,thereby effectively suppressing the steady-state component of the fault current.To address the active power imbalance induced by voltage sags,a dynamic active power reference correction method based on apparent power is designed to mitigate power angle oscillations and limit transient current.Moreover,an adaptive virtual impedance loop is implemented to enhance dynamic transient current-limiting performance during the fault initiation phase.This approach improves the responsiveness of the inner loop and ensures safe system operation under various fault severities.Under asymmetric fault conditions,a negative-sequence reactive current compensation strategy is incorporated to further suppress negative-sequence voltage and improve voltage symmetry.The proposed control scheme enables coordinated operation of multiple control objectives,including voltage support,current suppression,and power angle stability,across different fault scenarios.Finally,MATLAB/Simulink simulation results validate the effectiveness of the proposed strategy,showcasing its superior performance in current limiting and power angle stability,thereby significantly enhancing the system’s fault ride-through capability. 展开更多
关键词 Grid-forming converter multi-loop coordination negative-sequence control fault ride-through
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Monolithic Integration of Redox-Stable Sn-Pb Halide Perovskite Single-Crystalline Films for Durable Near-Infrared Photodetection
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作者 Rajendra Kumar Gunasekaran Jihoon Nam +9 位作者 Myeong-geun Choi Won Chang Choi Sunwoo Kim Doyun Im Yeonghun Yun Yun Hwa Hong Sang Hyeok Ryou Hyungwoo Lee Kwang Heo Sangwook Lee 《Nano-Micro Letters》 2026年第5期1-14,共14页
Tin-lead(Sn-Pb)halide perovskite single crystals combine narrow bandgaps,long carrier diffusion lengths,and low trap densities,positioning them as ideal candidates for near-infrared(NIR)optoelectronics.However,convent... Tin-lead(Sn-Pb)halide perovskite single crystals combine narrow bandgaps,long carrier diffusion lengths,and low trap densities,positioning them as ideal candidates for near-infrared(NIR)optoelectronics.However,conventional growth strategies rely on bulk crystallization at elevated temperatures,leading to uncontrolled nucleation,Sn^(2+)oxidation,and poor compatibility with planar integration.Here,we develop a coordination-engineered crystallization strategy that enables direct,lowtemperature growth of micrometer-thick Sn-Pb single-crystal thin films on device-compatible substrates.By modulating metal-solvent coordination strength using a low-donor number cosolvent system,we delineate a narrow processing window that stabilizes precursor speciation,lowers the nucleation barrier,and guides directional crystal growth under mild thermal conditions(<40℃).The resulting crystal films exhibit smooth morphology,high crystallinity,compositional uniformity,and ultralow trap densities(~3.98×10^(12)cm^(-3)).When integrated into NIR photodetectors,these films deliver high responsivity(0.51 A W^(-1)at 900 nm),specific detectivity up to 3.6×10^(12)Jones,fast response(~188μs),and>25,000 cycles of ambient operational stability.This approach establishes a scalable platform for redox-stable,low-temperature growth of Sn-Pb perovskite crystal films and expands the processing-structure-function landscape for next-generation infrared optoelectronics. 展开更多
关键词 Tin-lead perovskite Near-infrared photodetectors Single-crystal thin films Coordination chemistry Low-temperature crystallization
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Coupling Development Between Digital Economy–Agriculture Integration and Rural Revitalization in China:Spatiotemporal Disparities and Evolution Trends
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作者 Peng Xiangjun Jia Qingsong 《Contemporary Social Sciences》 2026年第1期71-89,共19页
This study aims to promote the optimization and upgrading of the economic structure in rural areas of China by focusing on the coupling coordination mechanism between digital economy–agriculture integration and rural... This study aims to promote the optimization and upgrading of the economic structure in rural areas of China by focusing on the coupling coordination mechanism between digital economy–agriculture integration and rural revitalization.By examining panel data from 30 Chinese provinces,autonomous regions,and municipalities between 2011 and 2022,the research constructs a weight-based evaluation system that integrates subjective and objective methods and a coupling coordination model to reveal its dynamic evolution patterns.Key findings indicate that digital economy–agriculture integration and rural revitalization achieve cross-coupling through critical activities.The impact of digital-agriculture integration on advancing rural revitalization lags by 2–3 years.Although the coupling development degree between the two systems continues to improve,it remains at the stage of primary coordination.Regional disparities are significant,showing a gradient pattern of“high degree of coupling development in the east and low degree of coupling development in the west.” 展开更多
关键词 digital economy-agriculture integration rural revitalization coupling coordination coupling development
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Hydrogen Ion Escape from Water's Body-Centered Cubic Lattice for Modelling IPMC'Electromechanical Behavior
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作者 Dehai Zhang Chenyu Xu +4 位作者 Jingxin Zhou Zhiqiang Zhang Zhimin Xu Yihao Li Dongjie Guo 《Journal of Bionic Engineering》 2026年第1期416-430,共15页
Ion-exchange Polymer-Metal Composites(IPMCs)gain huge attentions due to large deformation,rapid electromechanical response,and high energy conversion efficiency.Deflection of IPMC arises from the volumetric swelling e... Ion-exchange Polymer-Metal Composites(IPMCs)gain huge attentions due to large deformation,rapid electromechanical response,and high energy conversion efficiency.Deflection of IPMC arises from the volumetric swelling effect induced by the concentration gradient of hydrated cations between the two electrodes,thus the volume of hydrated cation deter-mines the motion magnitude and direction of IPMC.H ion is one of the most commonly used driving cations for IPMC.However,due to its unique characteristics,particularly the inability to accurately quantify its hydration volume,existing literatures primarily focus on the physical driving models for metallic cations,i.e.,Na+,no driving model for the H ion is reported until now.This paper proposes a novel model of H ion escape from the water's body-centered cubic lattice to count the hydration volume.Number(n)of water molecules carried by the H ion is solved by combining the Lennard-Jones potential energy function with Maxwell's velocity distribution.The specific n value is equivalent to 4.04 for the H ion inside Nafion electrolyte under a 3.0 V DC electric field.Substituting it into the classic Friction Model(proposed by Tadokoro et al.at 2000),actuation behaviors of H ion driven IPMC were therefore achieved through Matlab calculations and Abaqus simulations.The calculated results of dynamic displacement and force highly match to the experimental data form the Nafion IPMC actuator driven by same electric field,showing a highly reliability of the established escape model. 展开更多
关键词 IPMC Friction model Electromechanical coupling Number of coordinated water molecules Bodycentered cubic
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