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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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Analysis of the Brazilian railway system:concession renewals and the quest for a more diversified and competitive framework
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作者 Raphael Lúcio Reis dos Santos Conrado de Souza Rodrigues +1 位作者 Guilherme de Castro Leiva Armando Belato Pereira 《Railway Sciences》 2026年第1期29-48,共20页
Purpose-This paper provides a comprehensive analysis of the Brazilian freight railway system,examining the efficacy of the current concession renewal model in light of persistent structural problems such as market con... Purpose-This paper provides a comprehensive analysis of the Brazilian freight railway system,examining the efficacy of the current concession renewal model in light of persistent structural problems such as market concentration,cargo dependence on export commodities and underutilization of the network.Situating Brazil within the broader international debate on railway reforms,the paper evaluates whether the ongoing early renewal of concessions can deliver a more diversified and competitive freight system.Design/methodology/approach-The study adopts a sequential mixed-methods research design that integrates longitudinal quantitative analysis with qualitative institutional and policy evaluation.The quantitative component examines time-series indicators published by ANTT,DNIT and INFRA S.A.from 1999 to 2023 to identify structural patterns in traffic growth,investment,safety and market concentration.The qualitative component employs a process-tracing logic to reconstruct the evolution of concession renewals and the implementation of Railway Law 14.273/2021,drawing on concepts from regulatory economics,institutional theory and industrial organization.These empirical streams are synthesized through an analytical framework that connects three dimensions-regulatory design,market structure and system performance-allowing for a systematic assessment of how Brazil’s institutional configuration shapes incentives,competitive dynamics and network utilization.Findings-The analysis confirms that the early renewal of concessions has successfully secured substantial private investment for capacity expansion on existing trunk lines.However,it has perpetuated the vertically integrated model,reinforcing the market power of incumbent operators and failing to significantly promote intramodal competition or cargo diversification.The system remains dominated by iron ore and agricultural commodities,with general cargo representing a minuscule share.The new authorization regime and short-line railway policies present a viable pathway for market opening but face significant operational and institutional barriers to implementation.Originality/value-This research offers a timely and critical assessment of a pivotal moment in Brazilian railway policy.It moves beyond a simplistic evaluation of volume growth to a structural analysis of market failures and the interplay between concession renewal and regulatory innovation.The findings provide actionable insights for policymakers in Brazil and other emerging economies seeking to balance private investment with public interest goals in railway infrastructure,highlighting the necessity of complementary,pro-competitive measures alongside financial investment. 展开更多
关键词 Authorization regime Brazil Cargo diversification Economic resilience Infrastructure policy Market concentration Railway concessions Regulatory framework Short-line railways Transport planning Transport policy Transportation privatization
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A three-dimensional zinc(Ⅱ)metal-organic framework based on nitrogen-containing ligands for the detection of 2,4-dinitrophenylhydrazine and tetracycline
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作者 WANG Xuetian WANG Jijiang +3 位作者 TANG Long YUE Erlin WANG Xiao ZHANG Yuqi 《无机化学学报》 北大核心 2026年第4期861-871,共11页
A metal-organic framework{[Zn(L)_(0.5)(1,2,4,5-tpb)_(0.5)]·DMF·3H_(2)O}_(n)(1)was synthesized by solvothermal reaction,where H4L=5,5'-(ethane-1,2-diyl)diisophthalic acid,and 1,2,4,5-tpb=1,2,4,5-tetra(pyr... A metal-organic framework{[Zn(L)_(0.5)(1,2,4,5-tpb)_(0.5)]·DMF·3H_(2)O}_(n)(1)was synthesized by solvothermal reaction,where H4L=5,5'-(ethane-1,2-diyl)diisophthalic acid,and 1,2,4,5-tpb=1,2,4,5-tetra(pyridin-4-yl)benzene.The analysis of the single crystal structure indicates that L^(4-)and 1,2,4,5-tpb are connected with Zn(Ⅱ)to form a 2D layered structure,and the layers are linked by 1,2,4,5-tpb to form a 3D structure.1 can be used as a highly selective fluorescent probe for the detection of 2,4-dinitrophenylhydrazine(DNP)and tetracycline(TET),and the detection limits were 0.013 and 0.31μmol·L^(-1),respectively.1 was applied successfully to the determination of TET content in the Yanhe River water sample.CCDC:2466221. 展开更多
关键词 metal-organic frameworks Zn(Ⅱ) crystal structure fluorescent sensing
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Dual-Signal Colorimetric/Fluorescent Detection of Vibrio parahaemolyticus in Seafood Using a Multifunctional Aptamer-Conjugated Magnetic Covalent Organic Framework-CuO/Au Nanozyme
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作者 SUN Di YANG Xuewen +6 位作者 WANG Hui LIN Hongyong HE Xiaoxia HUO Zhenting LIU Yu YU Zhongjie JIANG Wei 《食品科学》 北大核心 2026年第6期23-40,共18页
In this study,a multifunctional aptamer-conjugated magnetic covalent organic framework(COF)-CuO/Au nanozyme(MCOF-CuO/Au@apt)was developed as a“three-in-one”platform for dual-signal colorimetric and fluorescent detec... In this study,a multifunctional aptamer-conjugated magnetic covalent organic framework(COF)-CuO/Au nanozyme(MCOF-CuO/Au@apt)was developed as a“three-in-one”platform for dual-signal colorimetric and fluorescent detection of Vibrio parahaemolyticus.The nanozyme integrated magnetic separation,peroxidase-like catalytic activity,and specific target recognition through an aptamer-based strategy.Upon binding to V.parahaemolyticus,the catalytic oxidation of tetra-aminophenylethylene(TPE-4A)by the nanozyme was selectively inhibited,resulting in distinct colorimetric and fluorescent signals that significantly enhanced the detection accuracy and reliability.The proposed method exhibited high sensitivity,with limits of detection(LOD)of 21 and 7 CFU/mL for the colorimetric and fluorescent assays,respectively.The performance of this method was validated using real seafood samples,including Penaeus vannamei,Mytilus coruscus,and Crassostrea gigas,which showed high recovery rates(101.11%-107.30%)and excellent reproducibility.The system also demonstrated strong specificity and accuracy under various conditions,confirming its robustness and practical applicability.Collectively,this innovative platform presents a promising solution for the rapid,versatile,and sensitive detection of V.parahaemolyticus in seafood,with considerable potential to advance food safety diagnosis and on-site monitoring. 展开更多
关键词 Vibrio parahaemolyticus dual-signal detection aptamer-based nanozyme magnetic covalent organic framework seafood safety
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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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Prelithiation of silicon encapsulated in MOF-derived carbon/ZnO framework for high-performance lithium-ion battery
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作者 Congcong Liu Yang Yang +6 位作者 Yu Yao Tao Dai Shitan Xu Shoumeng Yang Ghulam Ali Xianhong Rui Yan Yu 《Nano Materials Science》 2026年第2期298-306,共9页
Silicon possesses a high theoretical capacity,making it a potential contender for lithium-ion battery(LIB)anodes.Nonetheless,its practical usage is challenged by low electrical conductivity and significant volume expa... Silicon possesses a high theoretical capacity,making it a potential contender for lithium-ion battery(LIB)anodes.Nonetheless,its practical usage is challenged by low electrical conductivity and significant volume expansion during cycling.Here,we synthesized a novel silicon/carbon(Si/C)anode doped with ZnO via a template-derived method and high-temperature carbonization.The carbon structure,originated from metal-organic frameworks(MOFs)and ZnO doping,substantially enhanced the electrochemical properties of the composite material.It exhibited an initial capacity of 2100.3 mA h g^(-1)at a current density of 0.2 A g^(-1)and demonstrated excellent capacity retention over successive cycles.Moreover,the composite material displayed superior rate performance at higher current densities of 2 A g^(-1)and 3 A g^(-1).To address the low initial Coulombic efficiency(ICE)of siliconbased materials,we adopted a direct contact prelithiation approach and optimized the lithiation process by controlling the prelithiation time.After 30 min of prelithiation,the ICE reached 97.9%,thereby reducing the initial irreversible capacity loss(ICL)and realizing stable discharge-charge in subsequent cycles.This rational design provides valuable insights for achieving high-performance silicon anode. 展开更多
关键词 Metal-organic frameworks SILICON ZNO Prelithiation Lithium-ion batteries
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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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A review of hydrogen production and storage technologies for power system integration and applications
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作者 Ibrahim B.Mansir Paul C.Okonkwo Talal F.Qahtan 《Global Energy Interconnection》 2026年第1期83-107,共25页
The fast-changing trajectory of energy systems toward renewables requires flexible,low-emission technologies that can buffer supply intermittently and offer large-scale energy storage systems.Moreso,hydrogen is increa... The fast-changing trajectory of energy systems toward renewables requires flexible,low-emission technologies that can buffer supply intermittently and offer large-scale energy storage systems.Moreso,hydrogen is increasingly viewed as a multi-scale flexibility resource capable of supporting deep decarbonization in renewable-dominated power systems,yet existing reviews often treat production,storage,and conversion technologies in isolation.Hydrogen offers the ability to convert,store and reconvert energy on various timescales.This review critically analyses the current literature of hydrogen production and storage in relation to power systems integration,synthesizing technical,economic and operational advances.The study synthesizes recent advances in electrolysis,particularly PEM and high-temperature SOEC systems,together with emerging PEC routes,biomass-to-hydrogen processes,and long-duration storage technologies.It considers,for storage,the performance and maturity of compressed gas,liquid hydrogen,metal and complex hydrides,liquid organic hydrogen carriers,and geological formations.Integration studies show that the value of hydrogen is enhanced as the share of renewables increases,providing seasonal storage,grid balancing,and sector coupling via power-to-hydrogen-to-power configurations.Yet technical,economic and other hurdles such as conversion losses,infrastructure requirements,and safety considerations are still holding back widespread implementation.The review also underlines the value of policy frameworks,such as country-level hydrogen strategies,carbon pricing,tax incentives,and harmonized safety standards to speed up adoption and reduce barriers to costs.The review synthesizes offer planners,operators,and policymakers a clear roadmap for aligning hydrogen deployment strategies with evolving technical requirements and high-renewable power-system conditions.By summarizing what is known and discussing opportunities for the future,this review is intended to be a roadmap towards maximizing hydrogen in reaching a flexible,resilient and carbon free power system. 展开更多
关键词 Green hydrogen ELECTROLYSIS PHOTOELECTROCHEMICAL Biomass reforming Grid integration Policy frameworks
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Hybridization of polyoxometalates and metal-organic frameworks for effective tumor chemodynamic therapy and sonodynamic therapy
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作者 Runjie Wang Zhengya Yue +4 位作者 Wei Feng Yuan Sun Xin Hai Lei Wang Tiedong Sun 《Nano Materials Science》 2026年第1期244-253,共10页
Metal-organic frameworks(MOFs)with high porosity,specific surface area,and unique topologies are highly regarded for their applications in photocatalysis,medical treatment,and environmental pollutant degradation.Howev... Metal-organic frameworks(MOFs)with high porosity,specific surface area,and unique topologies are highly regarded for their applications in photocatalysis,medical treatment,and environmental pollutant degradation.However,due to the limitations of the tumor microenvironment(TME),traditional MOFs have limited efficacy in this environment.This paper designs multi-metal oxide-based heterostructure POMOFs nanoreactors with a nesting doll-like structure.This new structure not only exhibits therapeutic effects in TME but also utilizes ultrasound(US)to enhance the release of reactive oxygen species(ROS)for CDT&SDT co-therapy,becoming an effective sound sensitizer for destroying tumor cells.In summary,our study proposes an idea for constructing multi-metal oxide-based heterostructure MOFs nanoreactors material with a nesting doll-like structure to enhance ROS release and synergistically treat tumor diseases. 展开更多
关键词 Metal-organic frameworks POLYOXOMETALATES Chemodynamic therapy Sonodynamic therapy Heterogeneous structure
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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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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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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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Sedimentary Characteristics and Evolution of the High-resolution Sequence Stratigraphic Framework of the Taiyuan Formation in the Hangjinqi Area,Northern Ordos Basin
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作者 ZHAO Mingsheng TIAN Jingchun +1 位作者 SU Bingrui ZHANG Xiang 《Acta Geologica Sinica(English Edition)》 2026年第1期54-68,共15页
The Ordos Basin is a large superimposed hydrocarbon-bearing basin in China,and further research on the sedimentary characteristics and sedimentary evolution of the sequence framework of target layers is of great theor... The Ordos Basin is a large superimposed hydrocarbon-bearing basin in China,and further research on the sedimentary characteristics and sedimentary evolution of the sequence framework of target layers is of great theoretical and practical significance for guiding oil and gas exploration.The sedimentary facies and sedimentary evolution of the high-resolution sequence framework of the Carboniferous Taiyuan Formation in the Hangjinqi area have been systematically analyzed for the first time by drilling,logging and seismic data.The results show that four types of sequence interfaces can be identified in the Taiyuan Formation:regional unconformity surfaces,scour surfaces,lithologic-lithofacies transformation surfaces and flooding surfaces.According to the sedimentary response caused by the upward and downward movements of the base level at different levels,the Taiyuan Formation can be divided into 2 long-term cycles(LSC_(1)-LSC_(2)),4 mid-term cycles(MSC_(1)-MSC4)and 7 short-term cycles(SSC_(1)-SSC7).The long-and mid-term cycles correspond to members T_(1)and T_(2)and layers T_(1)-1,T_(1-2),T_(2-1),and T_(2)-2,respectively.Long-term cycles are dominated by C_(1);mid-term cycles are dominated by C_(1)and C_(2),followed by A2;and short-term cycles are dominated by C_(1),C_(2),A1 and A2.Under the high-resolution sequence stratigraphic framework,the Hangjinqi area underwent a transformation of fan delta and tidal flat depositional systems during the Taiyuan Formation sedimentary period.In the MSC_(1)-MSC_(2)stage,owing to a large-scale paleocontinent,the fan delta sedimentary body,which was limited in scale and scope,developed only in the southeastern corner and gradually transitioned basinward to tidal flat facies.In the MSC3-MSC4 stage,as the paleocontinent continuously decreased and the sedimentary range expanded,fan-delta plain sedimentation began in the study area.Several braided distributary channels with poor connectivity developed on the fan-delta plain,and between them were floodplains and peat swamps. 展开更多
关键词 high-resolution sequence framework sedimentary characteristics sedimentary evolution Taiyuan Formation Hangjinqi area northern Ordos Basin
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Self-assembly of disassemblable supramolecular organic frameworks for doxorubicin delivery,photofrin posttreatment phototoxicity inhibition and heparin neutralization
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作者 Ya-Jie Zhu Zhi-Min Lv +5 位作者 Hao-Feng Zhu Qi-Yan Qi Shang-Bo Yu Jia Tian Wei Zhou Zhan-Ting Li 《Chinese Chemical Letters》 2026年第1期320-326,共7页
Two supramolecular organic frameworks(SOFs)have been constructed from the co-assembly of biimidazolium-derived octacationic components and cucurbit[8]uril in water.Dynamic light scattering and ^(1)H NMR experiments re... Two supramolecular organic frameworks(SOFs)have been constructed from the co-assembly of biimidazolium-derived octacationic components and cucurbit[8]uril in water.Dynamic light scattering and ^(1)H NMR experiments reveal that both SOFs can undergo reversible assembly and disassembly at room temperature.One of the SOFs displays unprecedently high maximum tolerated dose of 120 mg/kg with mice,which improves by 40%compared with the highest value of the reported SOFs.In vitro and in vivo tests show that the SOF can adsorb doxorubicin and overcome the resistance of multidrugresistant MDR A549/ADR tumor cells to realize intracellular delivery,leading to enhanced antitumor efficacy.Moreover,it can also completely inhibit the posttreatment phototoxicity of photofrin and fully neutralize the anticoagulation of both unfractionated heparin and low molecular weight heparins through efficient inclusion and elimination or sequestration mechanism.As the first examples that undergo roomtemperature reversible assembly and disassembly,the new SOFs in principle allow for quantitative analysis of the molecular components in the body that is prerequisite for preclinical evaluation in the future. 展开更多
关键词 Supramolecular organic framework Self-assembly and disassembly Biosafety Drug delivery Porphyrin phototoxicity inhibition Heparin antagonism
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Facile and scale-up synthesis of cyano-functionalized covalent organic frameworks for selective gold recovery
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作者 Bo Li Yuanzhe Cheng +8 位作者 Xuyang Ma Dongxu Zhao Yang Zhang Yongxing Sun Jia Chen Li Wu Liang Zhao Hongdeng Qiu Yujian He 《Chinese Chemical Letters》 2026年第1期514-519,共6页
The recovery of gold from waste electronic and electric equipment(WEEE) has gained great attention with the increased number of WEEE,because it can largely alleviate the pressure on the environment and resources.Coval... The recovery of gold from waste electronic and electric equipment(WEEE) has gained great attention with the increased number of WEEE,because it can largely alleviate the pressure on the environment and resources.Covalent organic frameworks(COFs) are ideal adsorbents for gold recovery owing to their large surface area,good stability,easily functionalized ability,periodic structures,and definitive nanopores.Herein,a cyano-functionalized COF(COF-CN) with high crystallinity was large-scale prepared under mild conditions for the recovery of gold.The introduction of cyano groups enable COF-CN to exhibit excellent gold recovery performance,which possesses fast adsorption kinetics,high cycling stability,and adsorption capacity up to 663.67 mg/g.Excitingly,COF-CN showed extremely high selectivity for gold ions,even in the presence of various competing cations and anions.The COF-CN maintained excellent selectivity and removal efficiency in gold recovery experiments from WEEE.The facile synthesis of COF-CN and its outstanding selectivity in actual samples make it an attractive opportunity for practical gold recovery. 展开更多
关键词 Cyano functionalization Gold recovery Covalent organic frameworks Waste electronic and electric equipment SELECTIVITY
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Enhanced Photocatalytic Reduction of CO_(2) to Complete CO Mediated by Donor-Acceptor Covalent Organic Frameworks
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作者 Yi Li Longyan Wang +3 位作者 Deqi Fan Zhaolin Li Chengxiao Zhao Xiaofei Yang 《Energy & Environmental Materials》 2026年第2期332-340,共9页
The photocatalytic behavior of covalent organic frameworks(COFs)for carbon dioxide(CO_(2))reduction is dependent on the structure and physicochemical properties;CO_(2) photoreduction performance is generally influence... The photocatalytic behavior of covalent organic frameworks(COFs)for carbon dioxide(CO_(2))reduction is dependent on the structure and physicochemical properties;CO_(2) photoreduction performance is generally influenced by multiple effects rather than a single variable.Rational design and construction of donor(D)-acceptor(A)type COFs have emerged as an ideal strategy for improving photocatalytic CO_(2) reduction performance.However,it is still challenging to unveil the influence of building blocks on catalytic activity and selectivity of CO_(2) conversion in D–A COFs.Herein,we report a modified solvothermal method to constructβ-ketoenamine-linked COFs based on a one-step Schiff base condensation reaction.By employing 1,3,5-triformylphloroglucinol(TP),which enables both chemical stability and crystallinity of COFs as the electron acceptor,and 1,3,5-tris(4-aminophenyl)triazine(TAPT),2,4,6-tris(4-aminophenyl)pyridine(TAPP),and 1,3,5-tris(4-aminophenyl)benzene(TAPB)as the electron donors,respectively,we synthesized three distinct COF materials with different intensities of the D–A interaction,based on the molecule design,to regulate the microenvironment for CO_(2) photoreduction in pure water.The incorporation of D–A moieties into COFs remarkably accelerates charge separation and transport via enhanced D–A interaction or reinforced charge density difference.TP-TAPB COF,featuring the strongest D–A interaction,exhibited the highest CO production rate of 464.6μmol g^(-1) with nearly 100%selectivity,7.2 times higher activity than TP-TAPT. 展开更多
关键词 CO_(2)reduction covalent organic frameworks donor–acceptor PHOTOCATALYSIS
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Tetrahedral framework nucleic acids in the prevention and treatment of skin and mucosal diseases:Advances and prospects
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作者 Yuge Zhang Siqi Xu +4 位作者 Chenpeng Chen Haiyu Xian Qitao Wen Yunfeng Lin Tao Wang 《Chinese Chemical Letters》 2026年第2期135-144,共10页
The application of DNA hybridization technology,grounded in Watson-Crick base pairing,has facilitated the rational design of framework nucleic acids(FNAs)featuring adaptable shapes and dimensions.These nanostructures ... The application of DNA hybridization technology,grounded in Watson-Crick base pairing,has facilitated the rational design of framework nucleic acids(FNAs)featuring adaptable shapes and dimensions.These nanostructures exhibit remarkable stability and reproducibility,making them promising candidates for biomedical applications.Among various FNAs,tetrahedral FNAs(tFNAs),first introduced by Turberfield,are nanoscale assemblies of oligonucleotides that possess unique physical,chemical,and biological properties.Previous studies have demonstrated that tFNAs exhibit excellent cellular uptake,enhanced tissue permeability,and strong capabilities to promote cell migration,proliferation,and differentiation.Moreover,the intrinsic ability of tFNAs to efficiently penetrate cell membranes allows tFNAs to serve as versatile carriers for small-molecule drugs or functional oligonucleotides,thereby exerting significant anti-inflammatory,antioxidant,antibacterial,and immunomodulatory effects.These features highlight the therapeutic potential of tFNA-based complexes in skin,mucosal,and barrier tissue repair and regeneration.This review provides a comprehensive analysis of recent advances in the application of tFNAs for the prevention and treatment of skin,mucosal,and barrier tissue diseases,with a focus on their mechanisms of action and future prospects in regenerative medicine and targeted therapies. 展开更多
关键词 Tetrahedral framework nucleic acids DNA nanomaterials Nucleic acid drugs Skin repair and regeneration Mucosal lesions
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Ultra heat-resistant hydrogen-bonded organic framework:Breaking the thermal stability limit of high-energy materials
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作者 Bojun Tan Jinkang Dou +13 位作者 Jing Zhang Xiong Yang Jiatong Ren Changwei Tang Jian Su Gen Zhang Siwei Song Qinghua Zhang Binghui Duan Hongchang Mo Minghui Xu Xianming Lu Bozhou Wang Ning Liu 《Defence Technology(防务技术)》 2026年第3期300-306,共7页
The pursuit of heat-resistant energetic materials(HREMs)with thermal stability beyond 450℃ presents a significant challenge that has yet to be achieved.In this work,we develop an innovative electronic delocalization ... The pursuit of heat-resistant energetic materials(HREMs)with thermal stability beyond 450℃ presents a significant challenge that has yet to be achieved.In this work,we develop an innovative electronic delocalization strategy to design and synthesize a planar dizwitterionic diamino-bistriazolotetrazine,designated as TYX-1.The unique structural feature of TYX-1,including a nitrogen-rich fused ring system,planar conformation,and dizwitterionic configuration,combined with its hydrogen-bonded organic framework(HOF)structure,confer exceptional thermal stability(The onset temperature is 428℃,and the peak temperature is 473℃),high density(1.84 g/cm^(3)),and remarkable detonation performance(detonation velocity:8616 m/s).Furthermore,TYX-1 exhibits an impressive insensitivity(impact sensitivity>40 J;friction sensitivity>360 N),surpassing all previously reported HREMs.Theoretical calculations and single-crystal clearly indicate that the delocalizedπelectrons within the dizwitterionic bistriazolotetrazine rings and the HOF structure of TYX-1 are pivotal in ensuring its high thermal stability and high energy density.The discovery of TYX-1 marks a significant advancement in the field of HREMs and is anticipated to catalyze substantial progress in various high-temperature applications reliant on energetic materials. 展开更多
关键词 Ultra heat-resistant energetic materials Hydrogen-bonded organic framework A planar dizwitterionic structure Nitrogen-rich fused-ring skeleton
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Experimental Verification of Intrinsic Pressure Framework in an Activity Landscape
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作者 Zihao Sun Longfei Li +6 位作者 Chuyun Wang Jing Wang Huaicheng Chen Gao Wang Fangfu Ye Liyu Liu Mingcheng Yang 《Chinese Physics Letters》 2026年第1期322-326,共5页
The intrinsic pressure framework,which treats self-propelling force as an external force,provides a convenient and consistent description of mechanical equilibrium in active matter.However,direct experimental evidence... The intrinsic pressure framework,which treats self-propelling force as an external force,provides a convenient and consistent description of mechanical equilibrium in active matter.However,direct experimental evidence is still lacking.To validate this framework,here we employ a programmable robotic platform,where a single light-controlled wheeled robot travels in an activity landscape.Our experiments quantitatively demonstrate that the intrinsic pressure difference across the activity interface is balanced by the emerged polarization force.This result unambiguously confirms the theoretical predictions,thus validating the intrinsic pressure framework and laying the experimental foundation for the intrinsic pressure-based mechanical description of dry active matter. 展开更多
关键词 intrinsic pressure framework activity landscape intrinsic pressure difference robotic platform programmable robotic platformwhere self propelling force polarization force mechanical equilibrium
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