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PVA/CNC/COFs复合膜的水致变色行为及化学防护性能研究
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作者 段志漩 李君美 +4 位作者 贺佩芝 沈华 阳玉球 钱彬 刘丽芳 《棉纺织技术》 2026年第2期53-59,共7页
为开发一种兼具水响应性变色与可靠化学防护性能的先进材料,构建了聚乙烯醇(PVA)/纤维素纳米晶体(CNC)/共价有机骨架材料(COFs)复合膜。系统探究了复合膜浸水前后的力学性能、光学特性、水接触角、水蒸气透过系数及化学稳定性,并用傅里... 为开发一种兼具水响应性变色与可靠化学防护性能的先进材料,构建了聚乙烯醇(PVA)/纤维素纳米晶体(CNC)/共价有机骨架材料(COFs)复合膜。系统探究了复合膜浸水前后的力学性能、光学特性、水接触角、水蒸气透过系数及化学稳定性,并用傅里叶红外光谱揭示了其水致变色的微观机制。结果表明:COFs的引入赋予了复合膜显著的水响应性变色行为,ΔE达到21.24,其机制源于水分子与COFs亚胺键的n-π相互作用及体系氢键网络重组。浸水后风干膜发生溶胀软化,浸水前其水蒸气透过系数为1.016×10^(-12) g/(cm·s·Pa),浸水后为1.187×10^(-12) g/(cm·s·Pa)。复合膜在多数有机溶剂中展现出了良好的化学稳定性,且气体阻隔性能远优于常规聚合物膜。认为:制备的复合膜具有水致变色行为,同时兼顾化学防护所需的机械强度与化学稳定性,在智能化学防护领域应用前景广阔。 展开更多
关键词 水致变色行为 PVA/CNC/cofs复合膜 聚乙烯醇 断裂伸长率 共价有机骨架材料 智能化学防护服
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纳米COF材料调节细胞内Ca^(2+)浓度增强光动力治疗数字化实验
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作者 李维 许寒 +3 位作者 谷传灿 刘紫妍 李延安 耿琰 《大学化学》 2026年第1期354-362,共9页
本实验将前沿文献报道的纳米COF材料调节细胞内Ca^(2+)浓度增强光动力治疗设计成一个扩展性强、多层次的综合化学实验引入本科教学。设计并开发了一套数字化虚拟仿真实验教学平台,并将其作为本科生综合化学实验开展。该平台建立了关于... 本实验将前沿文献报道的纳米COF材料调节细胞内Ca^(2+)浓度增强光动力治疗设计成一个扩展性强、多层次的综合化学实验引入本科教学。设计并开发了一套数字化虚拟仿真实验教学平台,并将其作为本科生综合化学实验开展。该平台建立了关于实验对象的数学物理和数据库模型,利用计算机数字化技术对实验场景进行虚拟仿真,实现了实验过程的高精度还原和实验结果的可视化呈现。与原实验相比,数字化实验通过模块化设计支持学生自主探索实验变量对结果的影响,强化其对专业知识的深度理解,同时规避了时长过长、成本较高和安全风险等缺点。教学过程始终践行“以学生为中心”的OBE理念。教学实践表明,该实验有助于提升学生的仪器操作规范性和数据分析处理能力,有效调动学生的学习积极性和创造力,对优化实验资源配置,深化实验教学改革提供了新思路。 展开更多
关键词 cof 数字化实验 纳米材料
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Waste Coffee Grounds-Derived Micropores Carbon Framework as an Efficient Iodine Host for Zinc Iodine Battery
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作者 Lingfeng Zhu Xinwei Guan +10 位作者 Peng Li Yibo Ma Zhenfang Zhang Zhilong Yuan Congcong Zhang Ye Wang Hui Li Baohua Jia Hai Yu Yifei Sun Tianyi Ma 《Energy & Environmental Materials》 2025年第5期159-166,共8页
Aqueous zinc-iodine batteries(AZIBs)have attracted significant attention as the most promising next-generation energy storage technology due to their low cost,inherent safety,and high energy density.However,their prac... Aqueous zinc-iodine batteries(AZIBs)have attracted significant attention as the most promising next-generation energy storage technology due to their low cost,inherent safety,and high energy density.However,their practical application is hindered by the poor electronic conductivity of iodine cathodes and the severe shuttling effect of intermediate polyiodides.Here,we report a novel micropores carbon framework(MCF)synthesized from waste coffee grounds via a facile carbonization-activation process.The resultant MCF features an ultrahigh specific surface area and a high density of micropores,which not only physically confine iodine species to minimize iodine loss but also enhance the electronic conductivity of the composite cathode.Furthermore,biomass-derived heteroatom dopings(nitrogen functionalities)facilitate effective chemical anchoring of polyiodide intermediates,thereby mitigating the shuttle effect.UV–visible spectroscopy and electrochemical kinetic analyses further confirm the rapid transformation and inhibition mechanism of iodine species by MCF.Consequently,the MCF/I_(2)cathode delivers superior specific capacities of 238.3 mA h g^(−1)at 0.2 A g^(−1)and maintains outstanding cycling performance with a capacity retention of 85.2%after 1200 cycles at 1.0 A g^(−1).This work not only provides an important reference for the design of high-performance iodine-host porous carbon materials but also explores new paths for the sustainable,high-value utilization of waste biomass resources. 展开更多
关键词 iodine host micropores carbon framework polyiodide shuttle inhibition waste coffee grounds zinc iodine batteries
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Ligand-directed construction of cobalt-oxo cluster-based organic frameworks:Structural modulation,semiconductor,and antiferromagnetic properties
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作者 SHI Jinlian LIU Xiaoru XU Zhongxuan 《无机化学学报》 北大核心 2026年第1期45-54,共10页
Under hydrothermal and solvothermal conditions,two novel cobalt-based complexes,{[Co_(2)(CIA)(OH)(1,4-dtb)]·3.2H_(2)O}n(HU23)and{[Co_(2)(CIA)(OH)(1,4-dib)]·3.5H2O·DMF}n(HU24),were successfully construct... Under hydrothermal and solvothermal conditions,two novel cobalt-based complexes,{[Co_(2)(CIA)(OH)(1,4-dtb)]·3.2H_(2)O}n(HU23)and{[Co_(2)(CIA)(OH)(1,4-dib)]·3.5H2O·DMF}n(HU24),were successfully constructed by coordinatively assembling the semi-rigid multidentate ligand 5-(1-carboxyethoxy)isophthalic acid(H₃CIA)with the Nheterocyclic ligands 1,4-di(4H-1,2,4-triazol-4-yl)benzene(1,4-dtb)and 1,4-di(1H-imidazol-1-yl)benzene(1,4-dib),respectively,around Co^(2+)ions.Single-crystal X-ray diffraction analysis revealed that in both complexes HU23 and HU24,the CIA^(3-)anions adopt aκ^(7)-coordination mode,bridging six Co^(2+)ions via their five carboxylate oxygen atoms and one ether oxygen atom.This linkage forms tetranuclear[Co4(μ3-OH)2]^(6+)units.These Co-oxo cluster units were interconnected by CIA^(3-)anions to assemble into 2D kgd-type structures featuring a 3,6-connected topology.The 2D layers were further connected by 1,4-dtb and 1,4-dib,resulting in 3D pillar-layered frameworks for HU23 and HU24.Notably,despite the similar configurations of 1,4-dtb and 1,4-dib,differences in their coordination spatial orientations lead to topological divergence in the 3D frameworks of HU23 and HU24.Topological analysis indicates that the frameworks of HU23 and HU24 can be simplified into a 3,10-connected net(point symbol:(4^(10).6^(3).8^(2))(4^(3))_(2))and a 3,8-connected tfz-d net(point symbol:(4^(3))_(2)((4^(6).6^(18).8^(4)))),respectively.This structural differentiation confirms the precise regulatory role of ligands on the topology of metal-organic frameworks.Moreover,the ultraviolet-visible absorption spectra confirmed that HU23 and HU24 have strong absorption capabilities for ultraviolet and visible light.According to the Kubelka-Munk method,their bandwidths were 2.15 and 2.08 eV,respectively,which are consistent with those of typical semiconductor materials.Variable-temperature magnetic susceptibility measurements(2-300 K)revealed significant antiferromagnetic coupling in both complexes,with their effective magnetic moments decreasing markedly as the temperature lowered.CCDC:2457554,HU23;2457553,HU24. 展开更多
关键词 semi-rigid carboxylic acid ligands three-dimensional framework tetranuclear cobalt-oxo cluster semiconductor material antiferromagnetic magnetism
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Flexible High-Aspect-Ratio COF Nanofibers:Defect-Engineered Synthesis,Superelastic Aerogels,and Uranium Extraction Applications
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作者 Binbin Fan Jianyong Yu +2 位作者 Xueli Wang Yang Si Peixin Tang 《Nano-Micro Letters》 2026年第5期15-30,共16页
The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precis... The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precisely regulate the growth and stacking of COF grains through a moderate reversed Schiff base reaction,realizing the direct synthesis of COF nanofibers(CNFs)with high aspect ratio(L/D=103.05)and long length(>20μm).An individual CNF exhibits a biomimetic scale-like architecture,achieving superior flexibility and fatigue resistance under dynamic bending via a multiscale stress dissipation mechanism.Taking advantages of these structural features,we engineer CNF aerogels(CNF-As)with programmable porous structures(e.g.,honeycomb,lamellar,isotropic)via directional ice-template methodology.CNF-As demonstrate 100%COF content,high specific surface area(396.15 m^(2)g^(-1))and superelasticity(~0%elastic deformation after 500 compression cycles at 50%strain),outperforming most COF-based counterparts.Compared with the conventional COF aerogels,the unique structural features of CNF-A enable it to perform outstandingly in uranium extraction,with an 11.72-fold increment in adsorption capacity(920.12 mg g^(-1))and adsorption rate(89.9%),and a 2.48-fold improvement in selectivity(U/V=2.31).This study provides a direct strategy for the development of next-generation COF materials with outstanding functionality and structural robustness. 展开更多
关键词 Defect cleavage cof nanofibers Flexibility AEROGELS Uranium extraction
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Green and mild synthesis of Ca-MOF/COF functionalized silica microspheres in an acid-base tunable deep eutectic solvent for multi-mode chromatography
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作者 Yuanfei Liu Wanjiao Wei +5 位作者 Xu Liu Rui Hua Yanjuan Liu Yuefei Zhang Wei Chen Sheng Tang 《Chinese Chemical Letters》 2026年第1期547-551,共5页
Metal organic framework(MOF) assembled with coordination bonds has the disadvantage of poor stability that limits its application in the field of stationary phase,while covalent organic framework(COF)assembled through... Metal organic framework(MOF) assembled with coordination bonds has the disadvantage of poor stability that limits its application in the field of stationary phase,while covalent organic framework(COF)assembled through covalent bonds exhibits excellent structural stability.It has been shown that the stationary phases prepared by combining MOF and COF can make up for the poor stability of MOF@SiO_(2),and the MOF/COF composites have superior chromatographic separation performance.However,the traditional methods for preparing COF/MOF based stationary phases are generally solvent thermal synthesis.In this study,a green and low-cost synthesis method was proposed for the preparation of MOF/COF@SiO_(2) stationary phase.Firstly,COF@SiO_(2) was prepared in a choline chloride/ethylene glycol based deep eutectic solvent(DES).Secondly,another acid-base tunable DES prepared by mixing p-toluenesulfonic acid(PTSA)and 2-methylimidazole in different proportions was introduced as the reaction solvent and reactant for rapid synthesis of MOF/COF@SiO_(2).Compared with the toxic transition metal-based MOFs selected in most previous studies,a lightweight and non-toxic S-zone metal(calcium) based MOF was employed in this study.PTSA and calcium will form the calcium/oxygen-containing organic acid framework in acidic DES,which assembles with terephthalic acid dissolved in basic DES to form MOF.The strong hydrogen bonding effect of DES can facilitate rapid assembly of Ca-MOF.The obtained Ca-MOF/COF@SiO_(2) can be used for multi-mode chromatography to efficiently separate multiple isomeric/hydrophilic/hydrophobic analytes.The synthesis method of Ca-MOF/COF@SiO_(2) is green and mild,especially the use of acid-base tunable DES promotes the rapid synthesis of non-toxic Ca-MOF/COF@silica composites,which offers an innovative approach of greenly synthesizing novel MOF/COF stationary phases and extends their applications in the field of chromatography. 展开更多
关键词 Metal organic framework Covalent organic framework Deep eutectic solvent Silica composites Multi-mode chromatography
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Cationic covalent framework microenvironment steering CuPt alloy toward record-breaking photoelectrochemical ethane synthesis from CO_(2)
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作者 Fentahun Wondu Dagnaw Karim Harrath +9 位作者 Tao Zheng Yu-Ze Liu Huiwen Xue Wei Li Ze-Yu Zhang Zhen Li Xu-Bing Li Huaping Wang Qing-Xiao Tong Jing-Xin Jian 《Journal of Energy Chemistry》 2026年第1期339-349,I0009,共12页
Photoelectrochemical CO_(2)reduction to multi-carbon products fuels remains challenged by inefficient C–C coupling and competing proton reduction reaction.Herein,we designed a cationic covalent organic framework(COF+... Photoelectrochemical CO_(2)reduction to multi-carbon products fuels remains challenged by inefficient C–C coupling and competing proton reduction reaction.Herein,we designed a cationic covalent organic framework(COF+)to create an electrostatic microenvironment that synergizes with CuPt alloy nanoparticles for selective ethylene/ethane production.By spatially decoupling CO_(2)enrichment from proton exclusion,the COF^(+)/CuPt interface simultaneously facilitates CO_(2)accessibility while impeding H+migration,suppressing the hydrogen evolution reaction(HER).This unique microenvironment stabilizes key anionic intermediates(*COO^(−),*OCCO^(−))and promotes*CO dimerization,steering electron transfer toward C–C coupling.The optimized system achieves a record-high Faradaic efficiency of 51.5%±5.3%for ethane and 10.6%±2.5%for ethylene with a total C2+yield exceeding 62%at−0.25 V vs.RHE and high stability(>300 min),representing the highest performance for photoelectrochemical CO_(2)reduction to ethane.The combined analyses of in situ spectroscopy and theoretical calculations reveal that electrostatic field effects lower the energy barrier for*OCCO formation while accelerating hydrogenation kinetics.Therefore,this work demonstrates that microenvironment modification of the active site by cationic covalent organic framework is a versatile strategy for solar-driven CO_(2)conversion into value-added hydrocarbons. 展开更多
关键词 PHOTOELECTROCHEMICAL CO_(2)reduction cofs Reaction microenvironment C_(2)product
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Construction of Modifiable Phthalocyanine-Based Covalent Organic Frameworks with Irreversible Linking for Efficient Photocatalytic CO_(2)Reduction
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作者 Xuefei Zhou Shaowei Yang +5 位作者 Zhengyang Hu Zhanwei Chen Ying Guo Tianshuai Wang Qiuyu Zhang Hepeng Zhang 《Nano-Micro Letters》 2026年第4期435-448,共14页
Covalent organic frameworks(COFs)are considered promising catalysts for photocatalytic CO_(2)reduction reaction(pCO_(2)RR)due to facilitated regulations.However,the instability of COFs with dynamic reversible covalent... Covalent organic frameworks(COFs)are considered promising catalysts for photocatalytic CO_(2)reduction reaction(pCO_(2)RR)due to facilitated regulations.However,the instability of COFs with dynamic reversible covalent bonds and the limited modifiability of COFs with irreversible covalent bonds restricted the enhancement of the pCO_(2)RR performance.Herein,three phthalocyanine-based COFs with ether-linked,CoOP,CoPOP,and CoBOP,were successfully prepared via in situ polycondensation using modifiable bis-phthalonitrile.CoBOP achieved a record of syngas performance in pCO_(2)RR systems with photosensitizers and sacrificial agents(CO 83.7 mmol g^(-1)h^(-1)and H_254.7 mmol g^(-1)h^(-1)),surpassing most COF photocatalysts.Additionally,CoOP,CoPOP,and CoBOP exhibit stabilities in extreme environments owing to their irreversible covalent bonds.Experimental and density functional theory analyses confirm that the optimally matched the lowest unoccupied molecular orbital of the linking unit between the photosensitizer and active unit endowed Co BOP with the highest photoelectron transfer efficiency among the three catalysts,boosting its pCO_(2)RR activity.This work is highly instructive for designing COFs with structure-adjustable and irreversible covalent bonds. 展开更多
关键词 Photocatalytic CO_(2)RR Phthalocyanine-based cof Irreversible covalent bond Electronic property modulation Photoelectron transfer
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A Multi-Objective Adaptive Car-Following Framework for Autonomous Connected Vehicles with Deep Reinforcement Learning
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作者 Abu Tayab Yanwen Li +5 位作者 Ahmad Syed Ghanshyam G.Tejani Doaa Sami Khafaga El-Sayed M.El-kenawy Amel Ali Alhussan Marwa M.Eid 《Computers, Materials & Continua》 2026年第2期1311-1337,共27页
Autonomous connected vehicles(ACV)involve advanced control strategies to effectively balance safety,efficiency,energy consumption,and passenger comfort.This research introduces a deep reinforcement learning(DRL)-based... Autonomous connected vehicles(ACV)involve advanced control strategies to effectively balance safety,efficiency,energy consumption,and passenger comfort.This research introduces a deep reinforcement learning(DRL)-based car-following(CF)framework employing the Deep Deterministic Policy Gradient(DDPG)algorithm,which integrates a multi-objective reward function that balances the four goals while maintaining safe policy learning.Utilizing real-world driving data from the highD dataset,the proposed model learns adaptive speed control policies suitable for dynamic traffic scenarios.The performance of the DRL-based model is evaluated against a traditional model predictive control-adaptive cruise control(MPC-ACC)controller.Results show that theDRLmodel significantly enhances safety,achieving zero collisions and a higher average time-to-collision(TTC)of 8.45 s,compared to 5.67 s for MPC and 6.12 s for human drivers.For efficiency,the model demonstrates 89.2% headway compliance and maintains speed tracking errors below 1.2 m/s in 90% of cases.In terms of energy optimization,the proposed approach reduces fuel consumption by 5.4% relative to MPC.Additionally,it enhances passenger comfort by lowering jerk values by 65%,achieving 0.12 m/s3 vs.0.34 m/s3 for human drivers.A multi-objective reward function is integrated to ensure stable policy convergence while simultaneously balancing the four key performance metrics.Moreover,the findings underscore the potential of DRL in advancing autonomous vehicle control,offering a robust and sustainable solution for safer,more efficient,and more comfortable transportation systems. 展开更多
关键词 Car-following model DDPG multi-objective framework autonomous connected vehicles
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The Impact of Entrepreneurial Spirit on Firm-Level New Quality Productive Forces:An Empirical Analysis Based on the TOE Framework
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作者 Guo Yanqing Zhang Qiao 《Contemporary Social Sciences》 2026年第1期35-51,共17页
Accelerating the development of new quality productive forces(NQPF),with innovation at its core,has become essential for firm growth in the new era.Drawing on financial data from China's A-share listed companies s... Accelerating the development of new quality productive forces(NQPF),with innovation at its core,has become essential for firm growth in the new era.Drawing on financial data from China's A-share listed companies spanning the period 2010–2023,this study empirically investigates the impact of entrepreneurial spirit on firm-level NQPF.The results indicate that entrepreneurial spirit significantly promotes firm-level NQPF.Mechanism analysis indicates that entrepreneurial effort—underpinned by technological capital accumulation,effective incentive and constraint mechanisms,and a competitive market environment—plays a mediating role in this relationship.Further heterogeneity analysis reveals that,amid China's economic transition,the positive effects of entrepreneurial spirit are more pronounced in non-state-owned enterprises,high-tech firms,and newly established firms.Accordingly,systematic efforts should be pursued across the technological,organizational,and environmental(TOE)dimensions to optimize the cultivation of entrepreneurial spirit.In particular,greater emphasis should be placed on productive entrepreneurial spirit and the constructive role of entrepreneurial effort,so as to fully leverage their contribution to the advancement of firm-level NQPF. 展开更多
关键词 TOE framework entrepreneurial spirit firm-level NQPF entrepreneurial effort
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Metal-organic frameworks for sustainable recovery of precious metals:Advances in synthesis,applications,and multiscale mechanisms
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作者 Baocheng Zhou Guo Lin +3 位作者 Shixing Wang Tu Hu Yunfei An Libo Zhang 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期417-445,共29页
The recovery of precious metals(PMs)from secondary resources is critical for addressing global supply-chain vulnerabilities and sustainable resource utilization.This review systematically examines the transformative p... The recovery of precious metals(PMs)from secondary resources is critical for addressing global supply-chain vulnerabilities and sustainable resource utilization.This review systematically examines the transformative potential of metal-organic frameworks(MOFs)as next-generation adsorbents for PM recovery,focusing on their synthesis,functionalization,and multiscale adsorption mechanisms.We critically analyze conventional pyrometallurgical and hydrometallurgical methods and highlight their limitations in terms of selectivity,energy consumption,and secondary pollution.In contrast,MOFs offer tunable porosity,abundant active sites,and tunable surface chemistry,enabling efficient PM capture via synergistic physical and chemical adsorption.Advanced modification techniques,including direct synthesis and post-synthetic modification,are reviewed to propose strategies for enhancing the adsorption kinetics and selectivity for Au,Ag,Pt,and Pd.Key structure-property relationships are established through multiscale characterization and thermodynamic models,revealing the critical roles of hierarchical porosity,soft donor atoms,and framework stability.Industrial challenges,such as aqueous stability and scalability,are addressed via Zr-O bond strengthening,hydrophobic functionalization,and support immobilization.This study consolidates the experimental and theoretical advances in MOF-based PM recovery and provides a roadmap for translating laboratory innovations into practical applications within the circular-economy framework. 展开更多
关键词 metal-organic frameworks precious metal recovery FUNCTIONALIZATION ADSORPTION MECHANISMS circular economy
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Bioinspired Precision Peeling of Ultrathin Bamboo Green Cellulose Frameworks for Light Management in Optoelectronics
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作者 Yan Wang Yuan Zhang +2 位作者 Yingfeng Zuo Dawei Zhao Yiqiang Wu 《Nano-Micro Letters》 2026年第1期474-489,共16页
Cellulose frameworks have emerged as promising materials for light management due to their exceptional light-scattering capabilities and sustainable nature.Conventional biomass-derived cellulose frameworks face a fund... Cellulose frameworks have emerged as promising materials for light management due to their exceptional light-scattering capabilities and sustainable nature.Conventional biomass-derived cellulose frameworks face a fundamental trade-off between haze and transparency,coupled with impractical thicknesses(≥1 mm).Inspired by squid’s skin-peeling mechanism,this work develops a peroxyformic acid(HCOOOH)-enabled precision peeling strategy to isolate intact 10-μm-thick bamboo green(BG)frameworks—100×thinner than wood-based counterparts while achieving an unprecedented optical performance(88%haze with 80%transparency).This performance surpasses delignified biomass(transparency<40%at 1 mm)and matches engineered cellulose composites,yet requires no energy-intensive nanofibrillation.The preserved native cellulose I crystalline structure(64.76%crystallinity)and wax-coated uniaxial fibril alignment(Hermans factor:0.23)contribute to high mechanical strength(903 MPa modulus)and broadband light scattering.As a light-management layer in polycrystalline silicon solar cells,the BG framework boosts photoelectric conversion efficiency by 0.41%absolute(18.74%→19.15%),outperforming synthetic anti-reflective coatings.The work establishes a scalable,waste-to-wealth route for optical-grade cellulose materials in next-generation optoelectronics. 展开更多
关键词 Bamboo green Cellulose framework Chemical peeling Optical properties Light management
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Three-dimensional supramolecular polymer frameworks with precisely tunable and large apertures for enzyme encapsulation
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作者 Runtan Gao Yang Zong +2 位作者 Tingting Li Na Liu Zongquan Wu 《Chinese Chemical Letters》 2026年第1期361-367,共7页
Three-dimensional supramolecular organic frameworks with precisely tunable pore sizes are highly demanded for a wide range of applications,e.g.,encapsulating enzymes to enhance their stability,activity,and reusability... Three-dimensional supramolecular organic frameworks with precisely tunable pore sizes are highly demanded for a wide range of applications,e.g.,encapsulating enzymes to enhance their stability,activity,and reusability.However,precise control and tune the pore size of such frameworks still remains a significant challenge to date.In this study,we constructed supramolecular polymer frameworks using rigid tetrahedral star polyisocyanides with tunable length and sufficiently narrow distribution as building block.First,a series of tetrahedral four-arm star polyisocyanides with controlled chain lengths and narrow molecular weight distributions was prepared via the Pd(Ⅱ)-catalyzed living isocyanide polymerization.Then 2-ureido-4[1H]-pyrimidinone(Upy) unit was installed onto each chain-end of polyisocyanide arms via post-polymerization functionalization.Leveraging the supramolecular hydrogen bonding interactions between the terminal Upy units,well-ordered supramolecular polymer frameworks were readily obtained.Notably,the pore size was dependent on the chain length of the polyisocyanide arms.Precisely control the chain length of polyisocyanide arms,supramolecular polymer frameworks with pore sizes ranging from 5.06 nm to 9.72 nm were achieved.These frameworks,with tunable and large pore apertures,demonstrated exceptional capabilities in encapsulating enzymes of different sizes,such as lipase(TL),horseradish peroxidase(HRP),and glucose oxidase(GOx).The encapsulated enzymes exhibited significantly enhanced catalytic activity and durability.Moreover,the frameworks' tunable and large pore apertures facilitated the co-encapsulation of multiple enzymes,enabling efficient dual-enzyme cascade reactions. 展开更多
关键词 Supramolecular organic frameworks Living polymerization Supramolecular self-assembly Polyisocyanide Enzyme encapsulation
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Optimizing COF crystallinity for high-resolution GC separation
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作者 Chu Zeng Han Yang +1 位作者 Ming Xu Zhi-Yuan Gu 《Chinese Chemical Letters》 2026年第1期503-506,共4页
This research explores the influence of crystallinity on gas chromatographic(GC) separation using covalent organic frameworks(COFs) as stationary phases.Three COF materials(CTF-DCBs) with varying crystallinity were sy... This research explores the influence of crystallinity on gas chromatographic(GC) separation using covalent organic frameworks(COFs) as stationary phases.Three COF materials(CTF-DCBs) with varying crystallinity were synthesized and characterized.CTF-DCB-1,with superior crystallinity,demonstrated highselectivity GC separation of benzene isomers as well as styrene/phenylacetylene mixtures,while CTFDCB-2 and CTF-DCB-3 exhibited lower crystallinity and worse separation performance.Thermodynamic and kinetic tests showed that CTF-DCB-1 had the worst thermodynamic adsorption but low diffusion mass transfer resistance,which resulted in the best separation.Therefore,optimizing the crystallinity of COFs is necessary for balancing the kinetic diffusion and thermodynamic interactions towards the analytes,achieving high-performance GC stationary phases. 展开更多
关键词 Covalent organic framework Gas chromatography CRYSTALLINITY Kinetic diffusion Thermodynamic adsorption
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Advances in electrocatalytic and photocatalytic CO_(2)conversion to value-added chemicals using copper-based covalent organic frameworks
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作者 LI Yue LIU Ziqi +7 位作者 FENG Ke LI Yingdan NING Yue SHEN Li LU Jitao MENG Qingguo WANG Min WANG Haiying 《无机化学学报》 北大核心 2026年第1期1-22,共22页
CO_(2)reduction technology can promote the resource utilization of carbon and help alleviate global warming and energy supply pressure.It is an effective way to achieve energy conversion and utilization.Covalent organ... CO_(2)reduction technology can promote the resource utilization of carbon and help alleviate global warming and energy supply pressure.It is an effective way to achieve energy conversion and utilization.Covalent organic frameworks(COFs)are porous crystalline materials formed by connecting organic monomers through covalent bonds.They have the characteristics of functional diversity and rich chemical properties.Their advantages,such as high porosity,a wide range of visible light absorption,and excellent charge separation efficiency,give them good potential in CO_(2)capture,separation,and conversion.Currently,Cu is a key metal in the catalytic CO_(2)reduction reaction(CO_(2)RR)for the preparation of high-value-added chemicals.The preparation of highly stable and large-pore Cu-based COFs using COFs as an ideal sacrificial template for loading Cu can be used to develop high-performance electrocatalysts and photocatalysts.In this review,we discuss the latest advancements in this field,including the development of various Cu-based COFs and their applications as catalysts for CO_(2)RR.Here,we mainly introduce the synthesis strategies,some important characterization information,and the applications of electrocatalytic and photocatalytic CO_(2)conversion using these previously reported Cu-based COFs. 展开更多
关键词 copper-based covalent organic frameworks CO_(2)reduction reactions electrocatalytic CO_(2)conversion photocatalytic CO_(2)conversion
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Synergistic lock-anchor engineered diketopyrrolopyrrole-COFs for efficient photocatalytic uranium extraction
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作者 Fengtao Yu Xiaolong Zhang +5 位作者 Jie Xu Guihong Wu Huiying Lei Zhiwu Yu Jianding Qiu Jianli Hua 《Journal of Energy Chemistry》 2026年第1期284-293,I0007,共11页
As a key low-carbon energy source,nuclear power plays a vital role in the global transition toward sustainable energy.Photocatalytic uranium extraction from seawater(UES)offers a promising solution to ensure long-term... As a key low-carbon energy source,nuclear power plays a vital role in the global transition toward sustainable energy.Photocatalytic uranium extraction from seawater(UES)offers a promising solution to ensure long-term uranium supply but is challenged by ultra-low uranium concentrations and ion interference.To overcome these issues,we design three diketopyrrolopyrrole-based covalent organic frameworks(COFs)via a synergisticπ-extended lock and carboxyl-functionalized anchor molecular engineering strategy.Among them,TPy-DPP-COF features a covalently lockedπ-conjugated structure that enhances planarity,optimizes energy alignment,and minimizes exciton binding energy,thereby promoting charge transfer and suppressing recombination.Concurrently,carboxyl groups enable uranyl-specific coordination and create local electric fields to facilitate charge separation.These features contribute to the outstanding performance of TPy-DPP-COF,which achieves a high uranium adsorption capacity of 16.33 mg g−1 in natural seawater under irradiation,with only 29.3%capacity loss after 10 cycles,surpassing industrial benchmarks.Density functional theory(DFT)calculations and experimental studies reveal a synergistic photocatalysis-adsorption pathway,with DPP units acting as active sites for uranium reduction.This work highlights a molecular design strategy for developing efficient COF-based photocatalysts for practical marine uranium recovery. 展开更多
关键词 DIKETOPYRROLOPYRROLE Covalent organic frameworks Exciton binding energy Photocatalytic uranium extraction Synergistic effect
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CoOOH@COFs S-scheme heterojunction for efficient triclosan degradation in photocatalytic-peroxymonosulfate activation system:Enhanced interfacial electron transfer mechanism
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作者 Lu Zhang Baohua Wang +7 位作者 Wei Yang Lunan Ju Zihan Fu Lei Zhao Yunqi Jiang Hongyan Wang Xiansheng Wang Cong Lyu 《Chinese Chemical Letters》 2026年第1期570-576,共7页
Triclosan(TCS) poses harmful risks to ecosystems and human health owing to its endocrine-disrupting effects.Therefore,developing an efficient and sustainable technology to degrade TCS is urgently needed.Herein,cobalt ... Triclosan(TCS) poses harmful risks to ecosystems and human health owing to its endocrine-disrupting effects.Therefore,developing an efficient and sustainable technology to degrade TCS is urgently needed.Herein,cobalt oxyhydroxide @covalent organic frameworks(CoOOH@COFs) S-scheme heterojunction was synthesized,which combined the visible-light-driven photocatalysis and peroxymonosulfate(PMS) activation to synergistically generate abundant reactive oxygen species(ROSs) for TCS degradation.The degradation efficiency of TCS reached 100 % within 8 min in the Vis-CoOOH@COFs/PMS system,and the reaction rate constant was 0.456 min^(-1),which was nearly 1.90 and 2.85 times that of single Co OOH and COFs,and2.36 times that under dark condition,respectively.The density functional theory(DFT) calculations confirmed the energy band bending of CoOOH@COFs and S-scheme charge transport from COFs to Co OOH.Both experimental and theoretical analyses indicated that Co OOH@COFs in photocatalytic-PMS activation systems synergistically facilitated photo-generated carrier separation,enhanced interfacial electron transfer,accelerated PMS activation,and generated multiple ROSs.In particular,photogenerated electrons(e^(-))accelerated the Co(Ⅲ)/Co(Ⅱ) redox cycle,while the PMS captured the e-,which significantly decreased the charge combination of Co OOH@COFs.Radicals(O_(2)^(·-),^(·)OH,and SO_(4)^(·-)) and non-radicals(such as ^(1)O_(2),h^(+),and e^(-)) were both presented in the Vis-CoOOH@COFs/PMS system,with O_(2)^(-) playing a dominant role in TCS degradation.Furthermore,the pathway of TCS degradation and toxicity of intermediates were explored by DFT calculation and transformation product identification.Importantly,the environmentally friendly CoOOH@COFs S-scheme heterojunction exhibited excellent stability and reusability.In conclusion,this study innovatively designed an S-scheme heterojunction in the photocatalytic-PMS activation system,providing guidance and theoretical support for efficient and eco-friendly wastewater treatment. 展开更多
关键词 Covalent organic frameworks Cobalt oxyhydroxide S-scheme heterojunction Interfacial electron transfer Peroxymonosulfate activation
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A Hierarchical Attention Framework for Business Information Systems:Theoretical Foundation and Proof-of-Concept Implementation
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作者 Sabina-Cristiana Necula Napoleon-Alexandru Sireteanu 《Computers, Materials & Continua》 2026年第2期2055-2088,共34页
Modern business information systems face significant challenges in managing heterogeneous data sources,integrating disparate systems,and providing real-time decision support in complex enterprise environments.Contempo... Modern business information systems face significant challenges in managing heterogeneous data sources,integrating disparate systems,and providing real-time decision support in complex enterprise environments.Contemporary enterprises typically operate 200+interconnected systems,with research indicating that 52% of organizations manage three or more enterprise content management systems,creating information silos that reduce operational efficiency by up to 35%.While attention mechanisms have demonstrated remarkable success in natural language processing and computer vision,their systematic application to business information systems remains largely unexplored.This paper presents the theoretical foundation for a Hierarchical Attention-Based Business Information System(HABIS)framework that applies multi-level attention mechanisms to enterprise environments.We provide a comprehensive mathematical formulation of the framework,analyze its computational complexity,and present a proof-of-concept implementation with simulation-based validation that demonstrates a 42% reduction in crosssystem query latency compared to legacy ERP modules and 70% improvement in prediction accuracy over baseline methods.The theoretical framework introduces four hierarchical attention levels:system-level attention for dynamic weighting of business systems,process-level attention for business process prioritization,data-level attention for critical information selection,and temporal attention for time-sensitive pattern recognition.Our complexity analysis demonstrates that the framework achieves O(n log n)computational complexity for attention computation,making it scalable to large enterprise environments including retail supply chains with 200+system-scale deployments.The proof-of-concept implementation validates the theoretical framework’s feasibility withMSE loss of 0.439 and response times of 0.000120 s per query,demonstrating its potential for addressing key challenges in business information systems.This work establishes a foundation for future empirical research and practical implementation of attention-driven enterprise systems. 展开更多
关键词 Attention mechanisms business information systems theoretical framework enterprise architecture complex systems hierarchical attention
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IL/COF复合材料用于H_(2)/N_(2)吸附分离的高通量筛选研究
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作者 曹泽铭 汪朝旭 《广州化工》 2026年第1期70-72,共3页
在能源转换领域,需要高纯度的氢气作为能源载体,分离技术对提供纯净的氢气至关重要。基于巨正蒙特卡罗(GCMC)模拟方法,系统地研究了1300个IL/COFs复合材料在常温常压下对H_(2)/N_(2)混合气体的分离性能进行了高通量计算筛选。研究结果... 在能源转换领域,需要高纯度的氢气作为能源载体,分离技术对提供纯净的氢气至关重要。基于巨正蒙特卡罗(GCMC)模拟方法,系统地研究了1300个IL/COFs复合材料在常温常压下对H_(2)/N_(2)混合气体的分离性能进行了高通量计算筛选。研究结果表明材料的孔径在5.6~8Å、比表面积在140~870 m^(2)/g范围内,离子液体的负载量为15对时,材料对H_(2)/N_(2)的分离效果最佳。该计算结果可为今后定向设计与可控合成相关高性能IL/COFs复合分离材料提供理论参考。 展开更多
关键词 高通量筛选 共价有机框架 离子液体 吸附分离
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Confining Li^(+)Solvation in Core-Shell Metal-Organic Frameworks for Stable Lithium Metal Batteries at 100℃
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作者 Minh Hai Nguyen Jeongmin Shin +3 位作者 Mee-Ree Kim Quan Van Nguyen JinHyeok Cha Sangbaek Park 《Nano-Micro Letters》 2026年第4期718-734,共17页
The practical deployment of lithium metal batteries remains severely constrained,especially under elevated temperatures.Although metal-organic frameworks(MOFs)improve the thermal stability of liquid electrolytes by ca... The practical deployment of lithium metal batteries remains severely constrained,especially under elevated temperatures.Although metal-organic frameworks(MOFs)improve the thermal stability of liquid electrolytes by capturing them in well-ordered sub-nanopores,interparticle voids between MOF particles readily absorb liquid electrolyte,obscuring our understanding of the intrinsic role of nanopores in directing Li^(+)transport.To address this challenge,we introduce a one-dimensional(1D)MOF model architecture that eliminates interparticle effects and enables direct observation of Li^(+)solvation and de-solvation dynamics.Comparative studies of 1D HKUST-1 and ZIF-8 uncover distinct transport behaviors,supported by both experimental measurements and neural network potential-based molecular dynamics simulations.Building on these insights,we construct a hierarchical core-shell MOF architecture by integrating ZIF-8(core)and HKUST-1(shell)onto a hybrid fiber scaffold.This design harnesses the complementary strengths of both MOFs to achieve continuous ion pathways,directional Li^(+)conduction,and improved thermal and electrochemical resilience. 展开更多
关键词 Quasi-solid-state electrolyte Metal-organic frameworks Li metal batteries Thermal stability Lithium-ion solvation/de-solvation
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