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An enhanced fingerprint template protection scheme based on four-dimensional superchaotic system and dynamic DNA coding
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作者 Baiqiang Hu Jiahui Liu Zhe Liu 《Chinese Physics B》 2025年第7期262-272,共11页
With the rapid development of Internet of things technology,the efficiency of data transmission between devices has been significantly improved.However,the open network environment also poses serious security risks.Th... With the rapid development of Internet of things technology,the efficiency of data transmission between devices has been significantly improved.However,the open network environment also poses serious security risks.This paper proposes an innovative fingerprint template protection scheme,which generates key streams through an improved fourdimensional superchaotic system(4CSCS),uses the space-filling property of Hilbert curves to achieve pixel scrambling,and introduces dynamic DNA encoding to improve encryption.Experimental results show that this scheme has a large key space 2^(528),encrypts image information entropy of more than 7.9970,and shows excellent performance in defending against statistical attacks and differential attacks.Compared with existing methods,this scheme has significant advantages in terms of encryption performance and security,and provides a reliable protection mechanism for fingerprint authentication systems in the Internet of things environment. 展开更多
关键词 four-dimensional superchaotic system fingerprint template protection Zernike moments image encryption
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The Value of Four-Dimensional Ultrasound in Diagnosing Fetal Congenital Heart Disease:A Systematic Review and Meta-Analysis
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作者 Yuanyuan Li XingyueWang +5 位作者 Yucan Deng Runfang Tian Jinfeng Zhao Li Liu Panpan Sun Zhiguang Ping 《Congenital Heart Disease》 2025年第6期717-727,共11页
Background:Four-dimensional(4D)ultrasound is increasingly being used for prenatal diagnosis of congenital heart disease(CHD).We aimed to perform a systematic review and meta-analysis to evaluate its diagnostic accurac... Background:Four-dimensional(4D)ultrasound is increasingly being used for prenatal diagnosis of congenital heart disease(CHD).We aimed to perform a systematic review and meta-analysis to evaluate its diagnostic accuracy for fetal CHD.Methods:This systematic review was conducted in accordance with the PRISMA-DTA guidelines.We systematically searched eight databases for studies published up to July 22,2025.Data were extracted to calculate diagnostic accuracy metrics,study quality was assessed using QUADAS-2,and a bivariate random-effects model was used for the meta-analysis.Results:A total of 49 studies were included,comprising 45 retrospective and 4 prospective studies,which were mainly(91.8%)conducted in China.These studies involved 23,397 fetuses,among which 2115 were diagnosed with congenital heart disease.The pooled sensitivity of 4D ultrasound for diagnosing fetal congenital heart disease was 0.91(95%CI:0.89-0.93),the pooled specificity was 0.98(95%CI:0.97-0.99),and the area under the summary receiver operating characteristic(SROC)curve(AUC)was 0.98(95%CI:0.96-0.99).Although 4D ultrasound technology can be implemented as early as 11 weeks of gestation,its diagnostic sensitivity and specificity reached a superior level and stabilized at an average of 20 weeks of gestation(range 14-28 weeks).Meta-regression indicated that sample size and prior suspicion of fetal CHD were significant contributors to heterogeneity(p<0.05).Conclusion:Four-dimensional ultrasound has high diagnostic efficacy for fetal CHD and is suitable for prenatal screening of fetal CHD,and the diagnostic effect is optimal and stable at an average gestational age of 20 weeks(range 14-28 weeks). 展开更多
关键词 four-dimensional ultrasound congenital heart disease prenatal diagnosis diagnostic accuracy META-ANALYSIS
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Promising four-dimensional flow magnetic resonance imaging technique for vascular flow analysis in children
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作者 Jian-She Yang 《World Journal of Radiology》 2025年第4期47-49,共3页
Leesmidt et al present a comprehensive analysis of abdominal vascular flow in children using four-dimensional(4D)flow magnetic resonance imaging(MRI),aim to establish normal hemodynamic values for the abdominal viscer... Leesmidt et al present a comprehensive analysis of abdominal vascular flow in children using four-dimensional(4D)flow magnetic resonance imaging(MRI),aim to establish normal hemodynamic values for the abdominal visceral organs and to assess the feasibility of 4D flow MRI(4D-f-MRI)in this population.The researchers performed 4D-f-MRI on 9 pediatric patients with a history or suspi-cion of bowel pathology.Flow velocities were measured in the abdominal aorta and superior and inferior mesenteric arteries.The quality of the 4D-f-MRI images was evaluated,and the agreement between the measured flow velocities and those obtained from Duplex ultrasound was established.However,due to the specific limitations of this work,future studies should address the issues of small sample size and the specific age group design. 展开更多
关键词 four-dimensional flow magnetic resonance imaging Hemodynamic values Imaging DIAGNOSIS Vascular flow
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Cultivating Innovation and Entrepreneurship Abilities in Vocational College Graduates Based on a“Three-Dimensional and Four-Dimensional”System-Taking Guangdong Vocational Institute of Public Administration as an Example
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作者 Zhongkun Wu Zhixiong Zhang 《Journal of Contemporary Educational Research》 2025年第9期339-348,共10页
Addressing the core weaknesses in the innovation and entrepreneurship capabilities of vocational college graduates,such as market insight and risk tolerance,as well as issues with the existing training model,including... Addressing the core weaknesses in the innovation and entrepreneurship capabilities of vocational college graduates,such as market insight and risk tolerance,as well as issues with the existing training model,including courses that are disconnected from industry,a lack of systematic practical training,and superficial school-enterprise cooperation,this paper constructs a“three-dimensional,four-dimensional”training system.The“three-dimensional”foundational framework encompasses three pillars:curriculum,general education layer,professional integration layer,practical application layer,practice as in three stages:introductory,simulated,and practical,and support including dual mentors,policies,and platforms.The“four-dimensional”differentiated strategies include four implementation pathways:professional differentiation,stage differentiation,addressing capability shortcomings,and school-government-industry collaboration.This system is grounded in theories such as multiple intelligences theory and systems theory,forming a closed-loop process of“theoretical input—practical application—support mechanisms”.Based on the practices of Guangdong Vocational Institute of Public Administration,the paper proposes a competency development pathway tailored by major and stage,which can effectively enhance the innovative and entrepreneurial core competencies of vocational college graduates.This provides a replicable systematic solution for vocational college innovative and entrepreneurial education,supporting vocational education reform and regional economic development. 展开更多
关键词 Three-dimensional and four-dimensional system Vocational college graduates Innovation and entrepreneurship capabilities Training pathways School-enterprise collaboration
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Multi-source information response characteristics of surrounding rock catastrophic instability in deep roadways with four-dimensional support
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作者 Pengfei Yan Zhanguo Ma +5 位作者 Hongbo Li Peng Gong Haihui Zhao Chuanchuan Cai Mingshuo Xu Tianqi She 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第11期7183-7207,共25页
As coal mining progresses to greater depths,controlling the stability of surrounding rock in deep roadways has become an increasingly complex challenge.Although four-dimensional(4D)support theoretically offers unique ... As coal mining progresses to greater depths,controlling the stability of surrounding rock in deep roadways has become an increasingly complex challenge.Although four-dimensional(4D)support theoretically offers unique advantages in maintaining the stability of rock mass,the disaster evolution processes and multi-source information response characteristics in deep roadways with 4D support remain unclear.Consequently,a large-scale physical model testing system and self-designed 4D support components were employed to conduct similarity model tests on the surrounding rock failure process under unsupported(U-1),traditional bolt-mesh-cable support(T-2),and 4D support(4D-R-3)conditions.Combined with multi-source monitoring techniques,including stress–strain,digital image correlation(DIC),acoustic emission(AE),microseismic(MS),parallel electric(PE),and electromagnetic radiation(EMR),the mechanical behavior and multi-source information responses were comprehensively analyzed.The results show that the peak stress and displacement of the models are positively correlated with the support strength.The multi-source information exhibits distinct response characteristics under different supports.The response frequency,energy,and fluctuationsof AE,MS,and EMR signals,along with the apparent resistivity(AR)high-resistivity zone,follow the trend U-1>T-2>4D-R-3.Furthermore,multi-source information exhibits significantdifferences in sensitivity across different phases.The AE,MS,and EMR signals exhibit active responses to rock mass activity at each phase.However,AR signals are only sensitive to the fracture propagation during the plastic yield and failure phases.In summary,the 4D support significantlyenhances the bearing capacity and plastic deformation of the models,while substantially reducing the frequency,energy,and fluctuationsof multi-source signals. 展开更多
关键词 Physical model Deep roadway four-dimensional(4D)support Multi-source monitoring information Catastrophic instability process
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Assessment of superior mesenteric vascular flow quantitation in children using four-dimensional flow magnetic resonance imaging:A feasibility study
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作者 Kantheera Leesmidt Parmede Vakil +3 位作者 Sofia Verstraete Amanda R Liu Rachelle Durand Jesse Courtier 《World Journal of Radiology》 2025年第2期21-27,共7页
BACKGROUND Four-dimensional(4D)flow magnetic resonance imaging(MRI)is used as a noninvasive modality for assessing hemodynamic information with neurovascular and body applications.The application of 4D flow MRI for as... BACKGROUND Four-dimensional(4D)flow magnetic resonance imaging(MRI)is used as a noninvasive modality for assessing hemodynamic information with neurovascular and body applications.The application of 4D flow MRI for assessment of bowel disease in children has not been previously described.AIM To determine feasibility of superior mesenteric venous and arterial flow quantitation in pediatric patients using 4D flow MRI.METHODS Nine pediatric patients(7-14 years old,5 male and 4 female)with history or suspicion of bowel pathology,who underwent magnetic resonance(MR)enterography with 4D flow MR protocol from November 2022 to October 2023.Field strength/sequence:3T MRI using 4D flow MR protocol.Flow velocity and peak speed measurements were performed by two diagnostic radiologists placing the region of interest in perpendicular plane to blood flow on each cross section of superior mesenteric artery(SMA)and superior mesenteric vein(SMV)at three predetermined levels.Bland-Altman analysis,showed good agreement of flow velocity and peak speed measurements of SMV and SMA between two readers.RESULTS Mean SMV flow velocity increased from proximal to mid to distal(0.14 L/minute,0.17 L/minute,0.22 L/minute respectively).Mean SMA flow velocity decreased from proximal to mid to distal(0.35 L/minute,0.27 L/minute,0.21 L/minute respectively).Observed agreement was good for flow velocity measurements of SMV(mean bias-0.01 L/minute and 95%limits of agreement,-0.09 to 0.08 L/minute)and SMA(mean bias-0.03 L/minute and 95%limits of agreement,-0.23 to 0.17 L/minute)between two readers.Good agreement for peak speed measurements of SMV(mean bias-1.2 cm/second and 95%limits of agreement,-9.4 to 7.0 cm/second)and SMA(mean bias-3.2 cm/second and 95%limits of agreement,-31.4 to 24.9 cm/second).CONCLUSION Flow quantitation using 4D Flow is feasible to provide hemodynamic information for SMV and SMA in children. 展开更多
关键词 four-dimensional flow magnetic resonance imaging Superior mesenteric artery Superior mesenteric vein Bowel disease Mesenteric vessel flow analysis
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Transforming pediatric imaging:The role of four-dimensional flow magnetic resonance imaging in quantifying mesenteric blood flow
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作者 Arvind Mukundan Devansh Gupta +1 位作者 Riya Karmakar Hsiang-Chen Wang 《World Journal of Radiology》 2025年第6期174-178,共5页
The article"Assessment of superior mesenteric vascular flow quantitation in children using four-dimensional flow magnetic resonance imaging"suggests to use of four-dimensional(4D)flow magnetic resonance imag... The article"Assessment of superior mesenteric vascular flow quantitation in children using four-dimensional flow magnetic resonance imaging"suggests to use of four-dimensional(4D)flow magnetic resonance imaging(MRI)which is also to measure the blood flow in the superior mesenteric vein(SMV)in pediatric patients over the traditional method.The study focuses on assessing the potential of SMV and superior mesenteric artery(SMA)flow quantification in children utilizing 4D flow MRI.It included 9 pediatric patients aged 18 years and below where 5 were male and 4 were female patients,on whom magnetic resonance enterorrhaphy(MRE)with 4D flow MRI protocol was used.Statistical analysis was performed using MedCalc.Measurements of SMV and SMA between two readers were calculated using Bland-Altman analysis.The results stated that six patients showed no MRE evidence of active inflammatory bowel disease,two patients showed unmarkable bowel appearance on MRI and one patient showed normal MRE without endoscopy performed at the same timeframe.The study utilized available 4D flow MRI sequences in this study aiming to show the feasibility of 4D flow quantitation of SMA and SMV flow in pediatric patients.The study also discovered good agreement for both peak velocity and peak speed measurements of SMA and SMV. 展开更多
关键词 Pediatric radiology four-dimensional flow magnetic resonance imaging Mesenteric vasculature Bowel disease HEMODYNAMICS Superior mesenteric artery Superior mesenteric vein Noninvasive imaging Feasibility study Socioeconomic impact
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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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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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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 gas sensors:comprehensive review from principal,fabrication to application
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作者 Soon Hyeong So Seung Yong Lee +4 位作者 Hohyung Kang Hyegi Min Hee-Tae Jung Kyu Hyoung Lee Dae Woo Kim 《International Journal of Extreme Manufacturing》 2026年第1期1-31,共31页
Gas sensors are valuable tools for human applications,and extensive research has been conducted in this field.However,practical implementation has yet to be fully realized.In response,efforts have been made to explore... Gas sensors are valuable tools for human applications,and extensive research has been conducted in this field.However,practical implementation has yet to be fully realized.In response,efforts have been made to explore metal-organic frameworks(MOFs),a novel class of porous materials,as potential solutions.MOFs exhibit exceptional porosity and highly tunable chemical compositions and structures,giving rise to a wide range of unique physical and chemical properties.Significant progress has been achieved in developing MOF-based gas sensors,improving sensing performance for various gases.This review aims to provide a comprehensive understanding of MOF-based gas sensors,even for readers unfamiliar with MOFs and gas sensors.It covers the working principles of these sensors,fundamental concepts of MOFs,strategies for tuning MOF properties,fabrication techniques for MOF films,and recent studies on MOF and MOF-derivative gas sensors.Finally,current challenges,overlooked aspects,and future directions for fully exploiting the potential of MOFs in gas sensor development are discussed. 展开更多
关键词 metal organic framework gas sensor gas transport FABRICATION REVIEW
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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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Porphyrin-based metal-organic frameworks for photocatalytic carbon dioxide reduction:Current understanding and challenges
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作者 Hao Wu Rui Liu +1 位作者 Donghui Li Yun Hau Ng 《Nano Materials Science》 2026年第1期183-206,共24页
Photocatalytic carbon dioxide reduction reaction(CO_(2)RR)is a carbon-neutral strategy to address global energy use and its impact on climate.Metal oxide and metal chalcogenide catalysts are the most investigated cata... Photocatalytic carbon dioxide reduction reaction(CO_(2)RR)is a carbon-neutral strategy to address global energy use and its impact on climate.Metal oxide and metal chalcogenide catalysts are the most investigated catalysts for photocatalytic CO_(2)RR.Unfortunately,low CO_(2)adsorption ability and limited active sites of metal oxide and metal chalcogenide catalysts for CO_(2)RR make them less competitive compared to their industrial counterparts.Inspired by applications of porphyrin-based metal-organic framework(MOF)catalysts for hydrogen evolution and photodynamic therapy,the investigations of these porphyrin-based MOFs,including pristine and composite porphyrin-based MOFs in photocatalytic CO_(2)RR,have attracted significant attention in the last five years due to their excellent CO_(2)adsorption capacities,high porosity,high stability,exceptional optoelectronic properties,and multi-functionality.However,due to the difference in photocatalytic CO_(2)RR,several critical issues need to be addressed to achieve the rational design of advanced porphyrin-based MOF photocatalysts to improve activity,selectivity,and stability for CO_(2)RR.Here,we review recent developments in the field of porphyrin-based MOF CO_(2)RR photocatalysts,along with critical issues,challenges,and perspectives concerning porphyrin-based MOF catalysts for photocatalytic CO_(2)RR. 展开更多
关键词 PORPHYRIN Metal-organic framework PHOTOCATALYST Carbon dioxide conversion Charge separation
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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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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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Sub-nanometer resolution for anion conduction in a covalent-organic framework membrane:A hierarchical approach
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作者 Qiang Wang Zhiguo Qu Jianwen Jiang 《Journal of Energy Chemistry》 2026年第2期186-197,I0006,共13页
Ion conduction in covalent-organic framework(COF)membranes is vital for energy conversion and storage.Conventional phenomenological methods based on the Arrhenius equation offer micrometer-scale cognition of ion condu... Ion conduction in covalent-organic framework(COF)membranes is vital for energy conversion and storage.Conventional phenomenological methods based on the Arrhenius equation offer micrometer-scale cognition of ion conduction,whereas they ignore atomic details of ion-pore interactions and sophisticated conduction mechanisms,leaving gaps in high-resolution and bottom-up understanding of ion conduction in a nanoconfined space.In this study,we develop a hierarchical approach by holistically synergizing electronic structure calculations,first-principles molecular dynamics simulations,and thermodynamic integration methods to investigate the conduction of chloride(Cl^(-))and hydroxide(OH^(-))ions in a COF membrane.It is revealed that Cl^(-)ion with symmetric charge distribution undergoes weak solvation and tight ion-pore binding,which results in a tortuous conduction pathway,a high energy barrier,and slow diffusion based on the vehicular mechanism.In remarkable contrast,OH^(-)ion with heterogeneous charge distribution features strong solvation and weak ion-pore binding,and it jumps frequently via a smooth pathway and a low energy barrier.Moreover,OH^(-)ion conduction follows a mixed vehicular and Grotthuss mechanism,causing highly mutable ion identity and number,as well as superior dynamics due to proton transfer.This hierarchical approach provides sub-nanometer resolution insights into ion conduction,guiding intelligent membrane design and performance regulation to control ion conduction for emerging applications. 展开更多
关键词 Anion conduction Grotthuss mechanism Vehicular mechanism Free energy barrier Covalent-organic frameworks
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