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Evaluating Water Withdrawals for Regional Water Management Under a Data-driven Framework
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作者 LU Yan WANG Jinxin +2 位作者 LIU Jianzhong QIN Fen WANG Jiayao 《Chinese Geographical Science》 SCIE CSCD 2022年第3期521-536,共16页
With an increase in population and economic development,water withdrawals are close to or even exceed the amount of water available in many regions of the world.Modelling water withdrawals could help water planners im... With an increase in population and economic development,water withdrawals are close to or even exceed the amount of water available in many regions of the world.Modelling water withdrawals could help water planners improve the efficiency of water use,water resources allocation,and management in order to alleviate water crises.However,minimal information has been obtained on how water withdrawals have changed over space and time,especially on a regional or local scale.This research proposes a data-driven framework to help estimate county-level distribution of water withdrawals.Using this framework,spatial statistical methods are used to estimate water withdrawals for agricultural,industrial,and domestic purposes in the Huaihe River watershed in China for the period 1978–2018.Total water withdrawals were found to have more than doubled,from 292.55×10^(8)m^(3) in 1978 to 642.93×10^(8)m^(3) in 2009,and decreased to 602.63×10^(8)m^(3) in 2018.Agricultural water increased from 208.17×10^(8)m^(3) in 1978 to 435.80×10^(8)m^(3) in 2009 and decreased to 360.84×10^(8)m^(3) in 2018.Industrial and domestic water usage constantly increased throughout the 1978–2018 period.In 1978,industrial and domestic demands were 20.35×10^(8)m^(3) and 60.04×10^(8)m^(3),respectively,and up until 2018,the figures were 105.58×10^(8)m^(3) and 136.20×10^(8)m^(3).From a spatial distribution perspective,Moran’s I statistical results show that the total water withdrawal has significant spatial autocorrelation during 1978–2018.The overall trend was a gradual increase in 1978–2010 with withdrawal beginning to decline in 2010–2018.The results of Getis-Ord G_(i)^(*)statistical calculations showed spatially contiguous clusters of total water withdrawal in the Huaihe River watershed during1978–2010,and the spatial agglomeration weakened from 2010 to 2018.This study provides a data-driven framework for assessing water withdrawals to enable a deeper understanding of competing water use among economic sectors as well as water withdrawal modelled with proper data resource and method. 展开更多
关键词 water withdrawal data-driven framework spatial data analysis water coefficient Huaihe River watershed China
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Hybrid data-driven framework for shale gas production performance analysis via game theory, machine learning, and optimization approaches 被引量:3
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作者 Jin Meng Yu-Jie Zhou +4 位作者 Tian-Rui Ye Yi-Tian Xiao Ya-Qiu Lu Ai-Wei Zheng Bang Liang 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期277-294,共18页
A comprehensive and precise analysis of shale gas production performance is crucial for evaluating resource potential,designing a field development plan,and making investment decisions.However,quantitative analysis ca... A comprehensive and precise analysis of shale gas production performance is crucial for evaluating resource potential,designing a field development plan,and making investment decisions.However,quantitative analysis can be challenging because production performance is dominated by the complex interaction among a series of geological and engineering factors.In fact,each factor can be viewed as a player who makes cooperative contributions to the production payoff within the constraints of physical laws and models.Inspired by the idea,we propose a hybrid data-driven analysis framework in this study,where the contributions of dominant factors are quantitatively evaluated,the productions are precisely forecasted,and the development optimization suggestions are comprehensively generated.More specifically,game theory and machine learning models are coupled to determine the dominating geological and engineering factors.The Shapley value with definite physical meaning is employed to quantitatively measure the effects of individual factors.A multi-model-fused stacked model is trained for production forecast,which provides the basis for derivative-free optimization algorithms to optimize the development plan.The complete workflow is validated with actual production data collected from the Fuling shale gas field,Sichuan Basin,China.The validation results show that the proposed procedure can draw rigorous conclusions with quantified evidence and thereby provide specific and reliable suggestions for development plan optimization.Comparing with traditional and experience-based approaches,the hybrid data-driven procedure is advanced in terms of both efficiency and accuracy. 展开更多
关键词 Shale gas Production performance data-driven Dominant factors Game theory Machine learning Derivative-free optimization
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Chengdu’s Real Estate Market(2019-2024):An Integrated Framework for Data-Driven Insights and Policy Analysis
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作者 HU Xiao WU Jing +1 位作者 WANG Yan JIANG Xinyi 《Cultural and Religious Studies》 2026年第1期26-42,共17页
This study integrates multiple sources of data(transaction data,policy text,public opinion data)with visualization techniques(such as heat maps,time-series trend charts,3D building brochures)to construct an analysis f... This study integrates multiple sources of data(transaction data,policy text,public opinion data)with visualization techniques(such as heat maps,time-series trend charts,3D building brochures)to construct an analysis framework for the Chengdu real estate market.By using the Adaptive Neuro-Fuzzy Inference System(ANFIS)prediction model,spatial GIS(Geographic Information System analysis)analysis,and interactive dashboards,this study reveals market differentiation,policy impacts,and changes in demand structure,thereby providing decision support for the government,enterprises,and homebuyers. 展开更多
关键词 Chengdu City real estate market data-driven insights policy analysis
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Data-Driven Precision Training Model for Innovation and Entrepreneurship Talents in Universities:Theoretical Framework and Implementation Path
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作者 Shuai Yuan 《Journal of Electronic Research and Application》 2025年第6期237-243,共7页
Against the backdrop of the national innovation strategy and the digital transformation of education,the traditional“extensive”training model for innovation and entrepreneurship talents struggles to meet the persona... Against the backdrop of the national innovation strategy and the digital transformation of education,the traditional“extensive”training model for innovation and entrepreneurship talents struggles to meet the personalized development needs of students,making an urgent shift toward precision and intelligence necessary.This study constructs a four-dimensional integrated framework centered on data,“Goal-Data-Intervention-Evaluation”,and proposes a data-driven training model for innovation and entrepreneurship talents in universities.By collecting multi-source data such as learning behaviors,competency assessments,and practical projects,the model conducts in-depth analysis of students’individual characteristics and development potential,enabling precise decision-making in goal setting,teaching intervention,and practical guidance.Based on data analysis,a supportive system for personalized teaching and practical activities is established.Combined with process-oriented and summative evaluations,a closed-loop feedback mechanism is formed to improve training effectiveness.This model provides a theoretical framework and practical path for the scientific,personalized,and intelligent development of innovation and entrepreneurship education in universities. 展开更多
关键词 data-driven AI Innovation and entrepreneurship Talent training
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A systematic data-driven modelling framework for nonlinear distillation processes incorporating data intervals clustering and new integrated learning algorithm
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作者 Zhe Wang Renchu He Jian Long 《Chinese Journal of Chemical Engineering》 2025年第5期182-199,共18页
The distillation process is an important chemical process,and the application of data-driven modelling approach has the potential to reduce model complexity compared to mechanistic modelling,thus improving the efficie... The distillation process is an important chemical process,and the application of data-driven modelling approach has the potential to reduce model complexity compared to mechanistic modelling,thus improving the efficiency of process optimization or monitoring studies.However,the distillation process is highly nonlinear and has multiple uncertainty perturbation intervals,which brings challenges to accurate data-driven modelling of distillation processes.This paper proposes a systematic data-driven modelling framework to solve these problems.Firstly,data segment variance was introduced into the K-means algorithm to form K-means data interval(KMDI)clustering in order to cluster the data into perturbed and steady state intervals for steady-state data extraction.Secondly,maximal information coefficient(MIC)was employed to calculate the nonlinear correlation between variables for removing redundant features.Finally,extreme gradient boosting(XGBoost)was integrated as the basic learner into adaptive boosting(AdaBoost)with the error threshold(ET)set to improve weights update strategy to construct the new integrated learning algorithm,XGBoost-AdaBoost-ET.The superiority of the proposed framework is verified by applying this data-driven modelling framework to a real industrial process of propylene distillation. 展开更多
关键词 Integrated learning algorithm Data intervals clustering Feature selection Application of artificial intelligence in distillation industry data-driven modelling
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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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Distributed robust data-driven event-triggered control for QUAVs under stochastic disturbances
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作者 Chao Song Hao Li +2 位作者 Bo Li Jiacun Wang Chunwei Tian 《Defence Technology(防务技术)》 2026年第1期155-171,共17页
To address the issue of instability or even imbalance in the orientation and attitude control of quadrotor unmanned aerial vehicles(QUAVs)under random disturbances,this paper proposes a distributed antidisturbance dat... To address the issue of instability or even imbalance in the orientation and attitude control of quadrotor unmanned aerial vehicles(QUAVs)under random disturbances,this paper proposes a distributed antidisturbance data-driven event-triggered fusion control method,which achieves efficient fault diagnosis while suppressing random disturbances and mitigating communication conflicts within the QUAV swarm.First,the impact of random disturbances on the UAV swarm is analyzed,and a model for orientation and attitude control of QUAVs under stochastic perturbations is established,with the disturbance gain threshold determined.Second,a fault diagnosis system based on a high-gain observer is designed,constructing a fault gain criterion by integrating orientation and attitude information from QUAVs.Subsequently,a model-free dynamic linearization-based data modeling(MFDLDM)framework is developed using model-free adaptive control,which efficiently fits the nonlinear control model of the QUAV swarm while reducing temporal constraints on control data.On this basis,this paper constructs a distributed data-driven event-triggered controller based on the staggered communication mechanism,which consists of an equivalent QUAV controller and an event-triggered controller,and is able to reduce the communication conflicts while suppressing the influence of random interference.Finally,by incorporating random disturbances into the controller,comparative experiments and physical validations are conducted on the QUAV platforms,fully demonstrating the strong adaptability and robustness of the proposed distributed event-triggered fault-tolerant control system. 展开更多
关键词 data-driven QUAV control Fault diagnosis Event-triggered Non-conflicting communication
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Data-driven iterative calibration method for prior knowledge of earth-rockfilldam wetting model parameters
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作者 Shaolin Ding Jiajun Pan +4 位作者 Yanli Wang Lin Wang Han Xu Yiwei Lu Xudong Zhao 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1621-1632,共12页
Wetting deformation in earth-rockfill dams is a critical factor influencingdam safety.Although numerous mathematical models have been developed to describe this phenomenon,most of them rely on empirical formulations a... Wetting deformation in earth-rockfill dams is a critical factor influencingdam safety.Although numerous mathematical models have been developed to describe this phenomenon,most of them rely on empirical formulations and lack prior knowledge of model parameters,which is essential for Bayesian parameter inversion to enhance accuracy and reduce uncertainty.This study introduces a datadriven approach to establishing prior knowledge of earth-rockfill dams.Driving factors are utilized to determine the potential range of model parameters,and settlement changes within this range are calculated.The results are iteratively compared with actual monitoring data until the calculated range encompasses the observed data,thereby providing prior knowledge of the model parameters.The proposed method is applied to the right-bank earth-rockfilldam of Danjiangkou.Employing a Gibbs sample size of 30,000,the proposed method effectively calibrates the prior knowledge of the wetting model parameters,achieving a root mean square error(RMSE)of 5.18 mm for the settlement predictions.By comparison,the use of non-informative priors with sample sizes of 30,000 and 50,000 results in significantly larger RMSE values of 11.97 mm and 16.07 mm,respectively.Furthermore,the computational efficiencyof the proposed method is demonstrated by an inversion computation time of 902 s for 30,000 samples,which is notably shorter than the 1026 s and 1558 s required for noninformative priors with 30,000 and 50,000 samples,respectively.These findingsunderscore the superior performance of the proposed approach in terms of both prediction accuracy and computational efficiency.These results demonstrate that the proposed method not only improves the predictive accuracy but also enhances the computational efficiency,enabling optimal parameter identificationwith reduced computational effort.This approach provides a robust and efficientframework for advancing dam safety assessments. 展开更多
关键词 Earth-rockfilldam Wetting deformation Prior knowledge data-driven Bayesian inversion
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An electrochemical immunosensor based on an antibody-ferrocene-functionalized covalent organic framework
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作者 Qiang Fang Yingbo Lu +3 位作者 Jianying Huang Cheng Zhang Jing Wu Shijun Li 《Chinese Chemical Letters》 2026年第2期401-406,共6页
High-sensitive quantitative determination of alpha-fetoprotein(AFP)is of crucial importance for early clinical diagnosis of cancers.Herein,an AuNPs-free electrochemical immunosensor(Ab1-Fc-COF)was prepared from a carb... High-sensitive quantitative determination of alpha-fetoprotein(AFP)is of crucial importance for early clinical diagnosis of cancers.Herein,an AuNPs-free electrochemical immunosensor(Ab1-Fc-COF)was prepared from a carboxylic group enriched COF by post-functionalization with detecting antibody(Ab1)and ferrocene(Fc),and used for electrochemical detection of AFP.Due to the small,homogeneous pore size of the COF,Ab1 with a big size was immobilized on the surface of the COF,while Fc with a small size was covalently modified both on the surface and in the pores of COF.The covalently immobilized Ab1 was quite stable and beneficial to specifically detect AFP biomarkers.Meanwhile,the enriched Fc molecules not only improved the conductivity of the COF,but also effectively transferred and amplified the electrochemical signal.This proposed immunosensor exhibited high sensitivity in detecting AFP with a detection limit of 0.39 pg/mL(S/N of 3:1)and a wide linear response range spanning from 1 pg/mL to 100 ng/mL when plotted against logarithmic concentrations.Furthermore,this immunosensor showed excellent selectivity,stability and reproducibility in the testing of real samples.This study presents an innovative prototype for construction of a precious metal-free,antibody-directly-immobilized,simple and stable electrochemical immunoprobe. 展开更多
关键词 Covalent organic frameworks Post-functionalization FERROCENE Electrochemical immunosensors ALPHA-FETOPROTEIN
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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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Interface-directed porous aromatic framework nanoflakes for ultrafast quasi-homogeneous photocatalytic aerobic oxidation in air
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作者 Hengtao Lei Yuhui Zhai +6 位作者 Jian Song Xiaojun Zhao Ayesha Javaid Geng Tan Yuyang Tian Qinhe Pan Guangshan Zhu 《Science China Chemistry》 2026年第2期900-906,共7页
The development of efficient photocatalysts for crucial organic transformation,such as aerobic oxidation,remains challenging.Although powdered porous materials offer abundant accessible active sites,their application ... The development of efficient photocatalysts for crucial organic transformation,such as aerobic oxidation,remains challenging.Although powdered porous materials offer abundant accessible active sites,their application in liquid-phase catalysis is often limited by insufficient light absorption and inevitable charge recombination,which are inherent drawbacks of conventional heterogeneous catalysts.Here,through rational design and nanoscale-engineering of porous aromatic frameworks(PAFs)comprising porphyrin and porous organic cage,a quasi-homogeneous porous photocatalyst with high catalytic activity and controllable dimension was developed.The interface-directed growth in oil-in-water emulsion shaped the morphology of photoactive PAFs from powders to nanoflakes,which facilitated the light absorbance and catalyst-substrate interaction.Compared with PAF powders,PAF nanoflakes exhibited superior photocatalytic activity for aerobic oxidation.For mustard gas simulant(2-chloroethyl ethyl sulfide,CEES),PAF nanoflakes exhibited ultrafast detoxification rates in room air with a half-life(t_(1/2))as fast as 26s,which even exceeded other catalysts in pure oxygen.It also completely catalyzed the aerobic oxidation of thioether within 15 min,which is almost the fastest rate among any reported organic photocatalysts.Furthermore,the efficient catalytic performance under mild conditions caused by improved light enrichment,surface charge transfer and carrier lifetime was elucidated. 展开更多
关键词 porous aromatic framework morphology control nanoflake photocatalysis aerobic oxidation
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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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Polyoxometalate-constructed 2D irregular porous inorganic framework with single-crystal superprotonic conductivity
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作者 Mengnan Yang Shiyan Ji +3 位作者 Lijuan Xiong Pengtao Ma Jingping Wang Jingyang Niu 《Science China Chemistry》 2026年第2期729-736,共8页
This study presents a novel polyoxometalate(POM)constructed crystalline inorganic framework,featuring a 2D layered architecture with irregular porosity and inherent proton sources.This unique configuration establishes... This study presents a novel polyoxometalate(POM)constructed crystalline inorganic framework,featuring a 2D layered architecture with irregular porosity and inherent proton sources.This unique configuration establishes an intrinsic hydrogen bonding network that facilitates proton hopping(Grotthuss mechanism),achieving a[100]directional proton conductivity of 1.75×10^(-3)S cm^(-1)under a low relative humidity(RH)of 35%at 298 K.Notably,under elevated conditions(338 K,95%RH),it attains a superprotonic conductivity of 1.61 S cm^(-1),representing one of the highest values recorded for framework materials to date.Analysis of the molecular structure,pore geometry characteristics and topological connectivity,and water vapor adsorption experiment(offering proton diffusion coefficient),indicates that the exceptional water-mediated proton dynamics stem from the interlayer S-shaped irregular pore channels,which probably induce a siphon-like effect to significantly enhance the transport of hydrated protons under the vehicle mechanism.This work not only proposes a POM strategy for constructing 2D inorganic frameworks but also reveals the irregular pore channel-enhanced proton dynamics,providing new insights into the optimization of proton conductors. 展开更多
关键词 POLYOXOMETALATE 2D inorganic framework superprotonic conductivity proton dynamics
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Underscoring the polyimide-linkage in covalent organic frameworks and related applications
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作者 Qi Li Minqiao Liang +5 位作者 Huifen Zhuang Zhengyang Chen Yuxiang Jiang Xiaofei Chen Yifa Chen Ya-Qian Lan 《Chinese Chemical Letters》 2026年第2期6-18,共13页
Polyimide-linkage covalent organic frameworks(PI-COFs),as a subclass of the COFs material family,featuring the unique combination of excellent thermal stability of polyimide,tunable pore sizes,as well as high crystall... Polyimide-linkage covalent organic frameworks(PI-COFs),as a subclass of the COFs material family,featuring the unique combination of excellent thermal stability of polyimide,tunable pore sizes,as well as high crystallinity and surface area of COFs,are expected to be a novel type of promising crystalline porous material with potential applications in adsorption and separation,catalysis,chemical sensing,and energy storage.Therefore,it is increasingly important to summarize polyimide-linkage in COFs and related applications and provide in-depth insight to accelerate future development.In this review,we offer a comprehensive overview of recent advancements in PI-COFs,emphasizing their synthesis methods,design principles and applications.Finally,our brief outlooks on the current challenges and future developments of PI-COFs are provided.Overall,this review aims to guide the recent and future development of PI-COFs. 展开更多
关键词 Covalent organic frameworks Polyimide-linkage Heteroatomic sites Chemical stability Thermal stability
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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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A scalable ultramicroporous metal-organic framework for highly effective propylene/propane separation at elevated temperatures
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作者 Wen-Jiang Tian Ding-Yi Hu +6 位作者 Zi-Nan Chen Rong-Hua Wang Zi-Luo Fang Meng-Ru Yang Hao-Long Zhou Dong-Dong Zhou Xiao-Ming Chen 《Science China Chemistry》 2026年第2期754-760,共7页
The separation of propylene(C_(3)H_(6))and propane(C_(3)H_(8))presents a significant industrial challenge due to their similar molecular dimensions and physicochemical properties.Among various separation methods,molec... The separation of propylene(C_(3)H_(6))and propane(C_(3)H_(8))presents a significant industrial challenge due to their similar molecular dimensions and physicochemical properties.Among various separation methods,molecular sieving emerges as the most promising approach,but it will be significantly compromised at high temperatures due to the significant thermal motion.Here,we report a thermally robust zinc-based metal-organic framework(MOF)that can be synthesized on sub-kilogram scale and achieve exceptional C_(3)H_(6)/C_(3)H_(8) separation performances across a broad temperature range(298–353 K).Unlike conventional MOFs suffering from thermal lattice expansion to give poorer selectivity,this new MOF gives the adsorption capacity of C_(3)H_(6)essentially unchanged and that of C_(3)H_(8) negligible at elevated temperatures,outperforming most state-of-the-art adsorbents,in virtue of multiple hydrogen bonds at the aperture.Column breakthrough experiments confirmed the excellent separation capability,and showed no performance degradation over multi-round adsorption-desorption cycles at 353 K.This study addresses the critical challenge of the trade-off between temperature and selectivity in adsorptive separation,which offers new insights into the design of porous structures for highly effective separation at high temperatures. 展开更多
关键词 metal-organic framework propylene/propane separation scalable synthesis high-temperature separation GATING
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Planting nitrogen-rich motif into porous aromatic frameworks to boost redox potential and multi-ion storage for wide-temperature sodium-organic batteries
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作者 Mimi Zhang Linqi Cheng +3 位作者 Zhaoli Liu Fengchao Cui Fang Luo Heng-Guo Wang 《Science China Chemistry》 2026年第2期979-985,共7页
Redox-active porous aromatic frameworks(PAFs)have emerged as hopeful candidates for sodium-ion batteries(SIBs)in view of their porous structures,chemical stability and tunable architectures.Herein,we successfully synt... Redox-active porous aromatic frameworks(PAFs)have emerged as hopeful candidates for sodium-ion batteries(SIBs)in view of their porous structures,chemical stability and tunable architectures.Herein,we successfully synthesized two redox-active PAFs(PAF-305 and PAF-306)with different nitrogen-containing motifs,and demonstrated their application as cathode materials for SIBs.Density functional theory(DFT)calculations reveal that nitrogen-rich PAF-305 exhibits a lower lowest unoccupied molecular orbital(LUMO)energy level(-3.35 eV)and a narrower energy gap(E_(g))(2.40 eV)compared with nitrogen-poor PAF-306.As expected,PAF-305 displays outstanding electrochemical performance,comprising a high reversible capacity of 145.2 mAh g^(-1)at 0.05 A g^(-1)and satisfactory cycling stability with 92% capacity retention over 1000 cycles at 0.2 A g^(-1).Remarkably,PAF-305 maintains robust electrochemical properties across a wide temperature range(-20℃ to 50℃).Through a combination of experimental characterizations and theoretical calculations,the sodium-ion storage mechanism of PAF-305 is elucidated.This study not only provides a promising strategy for exploring other redox-active organic units in the design of novel PAFs,but also expands the potential applications of PAFs in energy storage systems. 展开更多
关键词 porous aromatic framework nitrogen-rich motif multi-ion storage wide temperature sodium-organic batteries
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Tetrahedral framework nucleic acid loaded celastrol ameliorates skin fibrosis by epithelial-mesenchymal transition prevention
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作者 Junxin Cheng Zhongyi Fang +2 位作者 Runqiao Yang Yunfeng Lin Sirong Shi 《Science China Materials》 2026年第3期1786-1796,共11页
Progressive skin fibrosis ultimately results in irreversible contractures,causing both joint dysfunction and cosmetic deformity.The key pathological features of skin fibrosis include persistent inflammation and abnorm... Progressive skin fibrosis ultimately results in irreversible contractures,causing both joint dysfunction and cosmetic deformity.The key pathological features of skin fibrosis include persistent inflammation and abnormal accumulation of the extracellular matrix(ECM),with epithelialmesenchymal transition(EMT)playing a critical role in disease progression.However,current therapeutic strategies for cutaneous fibrosis are largely palliative and often require repeated interventions,with limited efficacy.Celastrol(Cel)exerts anti-inflammatory and anti-fibrotic effects in skin tissue,but its clinical application is limited by poor bioavailability and a narrow therapeutic window.Tetrahedral framework nucleic acid(tFNA),a novel nanocarrier system,exhibits multiple advantages,including enhanced cellular uptake,improved cell viability,and intrinsic anti-fibrotic and anti-inflammatory properties.Therefore,this study applied tFNA-Cel complex(TCC)as an advanced nanotherapeutic agent,designed to exert a synergistic anti-fibrotic effect.In this study,an in vitro model of skin fibrosis was established using human keratinocyte(HaCaT)cells treated with 5 ng mL^(-1) transforming growth factor beta(TGF-β)for 24 h.The results showed that TCC significantly inhibited EMT progression by reducingα-smooth muscle actin(α-SMA)levels and increasing E-cadherin level.Compared to tFNA or Cel alone,TCC exhibited superior anti-fibrotic effects in the fibrosis model,as evidenced by modulation of SMAD family member 2(SMAD2)signaling and collagen I expression.Furthermore,the TCC group showed lower levels of nuclear factorκB p65(NF-κB p65),BCL-2-associated X protein(Bax),and reactive oxygen species(ROS)compared to the Cel or tFNA groups.These findings highlight TCC as a promising treatment for skin fibrosis,with its synergistic anti-fibrotic effects providing new therapeutic avenues. 展开更多
关键词 tetrahedral framework nucleic acids CELASTROL skin fibrosis nanodrug delivery system epithelial-mesenchymal transition
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