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STUDY ON THE FRAMEWORK SYSTEM OF DIGITAL AGRICULTURE 被引量:9
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作者 LIANGYong LUXiu-shan +2 位作者 ZHANGDe-gui LIANGFu RENZhi-bo 《Chinese Geographical Science》 SCIE CSCD 2003年第1期15-19,共5页
China is a great agricultural country with large population, limited soilresources and traditional farming mode, so the central government has been attaching greatimportance to the development of agriculture and put f... China is a great agricultural country with large population, limited soilresources and traditional farming mode, so the central government has been attaching greatimportance to the development of agriculture and put forward a new agricultural technologyrevolution ― the transformation from traditional agriculture to modern agriculture and fromextensive farming to intensive farming. Digital agriculture is the core of agriculturalinformatization. The enforcement of digital agriculture will greatly promote agricultural technologyrevolution, two agricultural transformations and its rapid development, and enhance China'scompetitive power after the entrance of WTO. To carry out digital agriculture, the frame system ofdigital agriculture is required to be studied in the first place. In accordance with the theory andtechnology of digital earth and in combination with the agricultural reality of China, this articleoutlines the frame system of digital agriculture and its main content arid technology support. 展开更多
关键词 digital agriculture framework system 3S technology spatial data
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Recent advances in zeolitic imidazolate frameworks as drug delivery systems for cancer therapy
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作者 Yuhan Wang Yixin Tang +4 位作者 Lei Guo Xi Yang Shanli Wu Ying Yue Caina Xu 《Asian Journal of Pharmaceutical Sciences》 2025年第1期94-118,共25页
Biological nanotechnologies based on functional nanoplatforms have synergistically catalyzed the emergence of cancer therapies.As a subtype of metal-organic frameworks(MOFs),zeolitic imidazolate frameworks(ZIFs)have e... Biological nanotechnologies based on functional nanoplatforms have synergistically catalyzed the emergence of cancer therapies.As a subtype of metal-organic frameworks(MOFs),zeolitic imidazolate frameworks(ZIFs)have exploded in popularity in the field of biomaterials as excellent protective materials with the advantages of conformational flexibility,thermal and chemical stability,and functional controllability.With these superior properties,the applications of ZIF-based materials in combination with various therapies for cancer treatment have grown rapidly in recent years,showing remarkable achievements and great potential.This review elucidates the recent advancements in the use of ZIFs as drug delivery agents for cancer therapy.The structures,synthesis methods,properties,and various modifiers of ZIFs used in oncotherapy are presented.Recent advances in the application of ZIF-based nanoparticles as single or combination tumor treatments are reviewed.Furthermore,the future prospects,potential limitations,and challenges of the application of ZIF-based nanomaterials in cancer treatment are discussed.We except to fully explore the potential of ZIF-based materials to present a clear outline for their application as an effective cancer treatment to help them achieve early clinical application. 展开更多
关键词 Metal-organic frameworks(MOFs) Zeolitic imidazolate frameworks(ZIF-8) ZIF-based nanoparticles Drug delivery Cancer treatment
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Research on the framework of the cultural heritage digitalization standards system
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作者 Huang Jing Yu Tianxiu +1 位作者 Liu Jianyu Qu Liang 《China Standardization》 2025年第4期60-63,共4页
The standards system for cultural heritage digitalization aims to build a clear and logically rigorous framework to guide the development and revision of relevant standards.This system enhances the scientific,systemat... The standards system for cultural heritage digitalization aims to build a clear and logically rigorous framework to guide the development and revision of relevant standards.This system enhances the scientific,systematic,and practical aspects of cultural heritage digitalization.This paper comprehensively analyzes the current status and needs of cultural heritage digitalization and standardization.It further examines the methods used to construct the standards system.Through comparative analysis,it establishes a lifecycle-based framework for cultural heritage.This framework accounts for the unique characteristics of cultural heritage and systematically integrates key processes such as collection,processing,storage,transmission,and utilization of data.The standards system is divided into six sections:general,data,information,knowledge,intelligence,and application.Based on the current digitalization efforts,this paper proposes key standardization directions for each section.This framework ensures the integrity and consistency of data throughout the digitalization process.It also supports the application of intelligent technologies in cultural heritage conservation,contributing to the sustainable preservation and utilization of cultural heritage data. 展开更多
关键词 cultural heritage digitalization standards system data lifecycle framework
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Ecological Security Assessment and Risk Management Framework for Recycled Water Systems in Landscape Hydration
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作者 Xinmiao Wang 《Journal of Architectural Research and Development》 2025年第2期28-31,共4页
Against the backdrop of intensifying global water scarcity,reclaimed water reuse has emerged as a critical strategy for ecological replenishment of landscape water bodies.However,its potential ecological risks remain ... Against the backdrop of intensifying global water scarcity,reclaimed water reuse has emerged as a critical strategy for ecological replenishment of landscape water bodies.However,its potential ecological risks remain underexplored.This study aims to establish a multidimensional ecological safety evaluation framework for reclaimed water replenishment systems and propose hierarchical risk prevention strategies.By integrating ecotoxicological assays(algae growth inhibition,Daphnia behavioral anomalies,zebrafish embryo toxicity),multimedia exposure modeling,and Monte Carlo probabilistic simulations,the risk contributions and spatial heterogeneity of typical pollutants are quantitatively analyzed.Results revealed that sulfamethoxazole(RQ=2.3)and diclofenac(RQ=1.8)posed high ecological risks,with their effects nonlinearly correlated with hydraulic retention time(HRT<3 days)and nutrient loading(TN>1.2 mg/L).A three-tier risk prevention system was developed based on the“source-pathway-receptor”framework:ozone-activated carbon pretreatment achieved 85%removal efficiency for pharmaceutical contaminants,ecological floating beds enhanced nitrogen and phosphorus retention by 40%-60%,and hydraulic regulation(flow velocity>0.1 m/s)effectively suppressed pathogen proliferation.The innovation of this study lies in establishing a chemical-biological-hydrological coupled risk quantification model for reclaimed water reuse scenarios.The hierarchical prevention standards have been incorporated into local reclaimed water management regulations,providing a scientific foundation and technical paradigm for sustainable landscape water replenishment. 展开更多
关键词 Recycled water systems Landscape hydration Ecological security assessment Risk management framework
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A Contrastive Analysis of English and Chinese Intonation Systems: An Auto- Segmental Metrical Framework
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作者 Qingbo Tian Ngee Thai Yap +1 位作者 Chwee Fang Ng Yasir Yahya 《Chinese Journal of Applied Linguistics》 2025年第3期366-400,480,481,共37页
Intonation refers to the use of supra-segmental features to convey pragmatic meanings at the sentence level in a linguistically structured way.The difference in intonation between the native language and a foreign lan... Intonation refers to the use of supra-segmental features to convey pragmatic meanings at the sentence level in a linguistically structured way.The difference in intonation between the native language and a foreign language may influence second language learners’acquisition of intonation.The purpose of this study is to explore the similarities and differences at the level of phonological representation between English and Chinese intonation systems.This study investigated English and Chinese intonation systems,respectively,from both form and meaning under the Auto-Segmental Metrical framework by referring to previous studies and illustrating examples.The results showed that in terms of form,there were notable differences in the structural elements and their inventories between the intonation systems of English and Chinese.In terms of meaning,assertions were represented by different structural elements in English and Chinese intonation systems;the types of structural elements in English intonation possessed the capability to convey complex and subtle meanings,contrasting with the comparatively simpler nature of Chinese intonation.The results reveal that Chinese EFL learners demonstrate considerable difficulties in the production of the structural elements of English intonation and their combinations due to L1 intonation interference. 展开更多
关键词 acquisition of L2 intonation auto-segmental metrical framework Chinese intonation cross-linguistic effects English intonation
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Construction of a Teaching System Through School-enterprise Collaboration in an Integration and Innovation Framework:A Case Study of the Internet of Things Specialization in the Software Engineering Program
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作者 Jing Tang Donglai Fu +2 位作者 Jun Hong Guoyu Qi Yan Qiang 《计算机教育》 2025年第3期41-47,共7页
The advancement of Internet of Things(IoT)technology is driving industries toward intelligent digital transformation,highlighting the crucial role of software engineering.Despite this,the integration of software engin... The advancement of Internet of Things(IoT)technology is driving industries toward intelligent digital transformation,highlighting the crucial role of software engineering.Despite this,the integration of software engineering into IoT engineering education remains underexplored.To address this gap,the School of Software at North University of China,in collaboration with QST Innovation Technology Group Co.,Ltd.(QST),has developed an innovative educational mechanism.This initiative focuses on the software engineering IoT track and optimizes the teaching process through the outcome-based education(OBE)concept.It incorporates military-industrial characteristics,introduces advanced information and technology curricula,and enhances laboratory infrastructure.The goal is to cultivate innovative talents with unique capabilities,thereby fostering the comprehensive development and application of IoT technology. 展开更多
关键词 Software engineering IoT track School-enterprise collaboration Integration and innovation framework Outcome-based education
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Research on multi-view collaborative detection system for UAV swarms based on Pix2Pix framework and BAM attention mechanism
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作者 Yan Ding Qingxin Cao +2 位作者 Bozhi Zhang Peilin Li Zhongjiao Shi 《Defence Technology(防务技术)》 2025年第4期213-226,共14页
Drone swarm systems,equipped with photoelectric imaging and intelligent target perception,are essential for reconnaissance and strike missions in complex and high-risk environments.They excel in information sharing,an... Drone swarm systems,equipped with photoelectric imaging and intelligent target perception,are essential for reconnaissance and strike missions in complex and high-risk environments.They excel in information sharing,anti-jamming capabilities,and combat performance,making them critical for future warfare.However,varied perspectives in collaborative combat scenarios pose challenges to object detection,hindering traditional detection algorithms and reducing accuracy.Limited angle-prior data and sparse samples further complicate detection.This paper presents the Multi-View Collaborative Detection System,which tackles the challenges of multi-view object detection in collaborative combat scenarios.The system is designed to enhance multi-view image generation and detection algorithms,thereby improving the accuracy and efficiency of object detection across varying perspectives.First,an observation model for three-dimensional targets through line-of-sight angle transformation is constructed,and a multi-view image generation algorithm based on the Pix2Pix network is designed.For object detection,YOLOX is utilized,and a deep feature extraction network,BA-RepCSPDarknet,is developed to address challenges related to small target scale and feature extraction challenges.Additionally,a feature fusion network NS-PAFPN is developed to mitigate the issue of deep feature map information loss in UAV images.A visual attention module(BAM)is employed to manage appearance differences under varying angles,while a feature mapping module(DFM)prevents fine-grained feature loss.These advancements lead to the development of BA-YOLOX,a multi-view object detection network model suitable for drone platforms,enhancing accuracy and effectively targeting small objects. 展开更多
关键词 Drone swarm systems Reconnaissance and strike Image generation Multi-view detection Pix2Pix framework Attention mechanism
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Single-image super-resolution of gamma-ray imaging system using deep denoiser prior based on plug-and-play framework
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作者 Guo-Guang Li Liang Sheng +6 位作者 Bao-Jun Duan Yang Li Yan Song Zi-Jian Zhu Wei-Peng Yan Dong-Wei Hei Qing-Zi Xing 《Matter and Radiation at Extremes》 2025年第2期56-70,共15页
Gamma-ray imaging systems are powerful tools in radiographic diagnosis.However,the recorded images suffer from degradations such as noise,blurring,and downsampling,consequently failing to meet high-precision diagnosti... Gamma-ray imaging systems are powerful tools in radiographic diagnosis.However,the recorded images suffer from degradations such as noise,blurring,and downsampling,consequently failing to meet high-precision diagnostic requirements.In this paper,we propose a novel single-image super-resolution algorithm to enhance the spatial resolution of gamma-ray imaging systems.A mathematical model of the gamma-ray imaging system is established based on maximum a posteriori estimation.Within the plug-and-play framework,the half-quadratic splitting method is employed to decouple the data fidelit term and the regularization term.An image denoiser using convolutional neural networks is adopted as an implicit image prior,referred to as a deep denoiser prior,eliminating the need to explicitly design a regularization term.Furthermore,the impact of the image boundary condition on reconstruction results is considered,and a method for estimating image boundaries is introduced.The results show that the proposed algorithm can effectively addresses boundary artifacts.By increasing the pixel number of the reconstructed images,the proposed algorithm is capable of recovering more details.Notably,in both simulation and real experiments,the proposed algorithm is demonstrated to achieve subpixel resolution,surpassing the Nyquist sampling limit determined by the camera pixel size. 展开更多
关键词 deep denoiser prior enhance spatial resolution maximum posteriori estimationwithin radiographic diagnosishoweverthe maximum posteriori estimation gamma ray imaging plug play framework recorded images
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Porous framework materials for energy&environment relevant applications:A systematic review 被引量:7
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作者 Yutao Liu Liyu Chen +16 位作者 Lifeng Yang Tianhao Lan Hui Wang Chenghong Hu Xue Han Qixing Liu Jianfa Chen Zeming Feng Xili Cui Qianrong Fang Hailong Wang Libo Li Yingwei Li Huabin Xing Sihai Yang Dan Zhao Jinping Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第2期217-310,共94页
Carbon peaking and carbon neutralization trigger a technical revolution in energy&environment related fields.Development of new technologies for green energy production and storage,industrial energy saving and eff... Carbon peaking and carbon neutralization trigger a technical revolution in energy&environment related fields.Development of new technologies for green energy production and storage,industrial energy saving and efficiency reinforcement,carbon capture,and pollutant gas treatment is in highly imperious demand.The emerging porous framework materials such as metal–organic frameworks(MOFs),covalent organic frameworks(COFs)and hydrogen-bonded organic frameworks(HOFs),owing to the permanent porosity,tremendous specific surface area,designable structure and customizable functionality,have shown great potential in major energy-consuming industrial processes,including sustainable energy gas catalytic conversion,energy-efficient industrial gas separation and storage.Herein,this manuscript presents a systematic review of porous framework materials for global and comprehensive energy&environment related applications,from a macroscopic and application perspective. 展开更多
关键词 Porous framework materials CATALYSIS SEPARATION Gas storage Carbon neutrality
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Systematic Security Guideline Framework through Intelligently Automated Vulnerability Analysis
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作者 Dahyeon Kim Namgi Kim Junho Ahn 《Computers, Materials & Continua》 SCIE EI 2024年第3期3867-3889,共23页
This research aims to propose a practical framework designed for the automatic analysis of a product’s comprehensive functionality and security vulnerabilities,generating applicable guidelines based on real-world sof... This research aims to propose a practical framework designed for the automatic analysis of a product’s comprehensive functionality and security vulnerabilities,generating applicable guidelines based on real-world software.The existing analysis of software security vulnerabilities often focuses on specific features or modules.This partial and arbitrary analysis of the security vulnerabilities makes it challenging to comprehend the overall security vulnerabilities of the software.The key novelty lies in overcoming the constraints of partial approaches.The proposed framework utilizes data from various sources to create a comprehensive functionality profile,facilitating the derivation of real-world security guidelines.Security guidelines are dynamically generated by associating functional security vulnerabilities with the latest Common Vulnerabilities and Exposure(CVE)and Common Vulnerability Scoring System(CVSS)scores,resulting in automated guidelines tailored to each product.These guidelines are not only practical but also applicable in real-world software,allowing for prioritized security responses.The proposed framework is applied to virtual private network(VPN)software,wherein a validated Level 2 data flow diagram is generated using the Spoofing,Tampering,Repudiation,Information Disclosure,Denial of Service,and Elevation of privilege(STRIDE)technique with references to various papers and examples from related software.The analysis resulted in the identification of a total of 121 vulnerabilities.The successful implementation and validation demonstrate the framework’s efficacy in generating customized guidelines for entire systems,subsystems,and selected modules. 展开更多
关键词 framework AUTOMATION vulnerability analysis SECURITY GUIDELINES
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Rational design of new in situ reduction of Ni(II)catalytic system for low-cost and large-scale preparation of porous aromatic frameworks
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作者 Shanshan Wang Yue Wu +3 位作者 Wenxiang Zhang Hao Ren Guangshan Zhu Heping Ma 《Carbon Energy》 SCIE EI CAS CSCD 2024年第5期105-113,共9页
Porous aromatic framework 1(PAF-1)is an extremely representative nanoporous organic framework owing to its high stability and exceptionally high surface area.Currently,the synthesis of PAF-1 is catalyzed by the Ni(COD... Porous aromatic framework 1(PAF-1)is an extremely representative nanoporous organic framework owing to its high stability and exceptionally high surface area.Currently,the synthesis of PAF-1 is catalyzed by the Ni(COD)2/COD/bpy system,suffering from great instability and high cost.Herein,we developed an in situ reduction of the Ni(II)catalytic system to synthesize PAF-1 in low cost and high yield.The active Ni(0)species produced from the NiCl_(2)/bpy/NaI/Mg catalyst system can effectively catalyze homocoupling of tetrakis(4-bromophenyl)methane at the room temperature to form PAF-1 with high Brunauer-Emmett-Teller(BET)-specific surface area up to 4948 m^(2) g^(−1)(Langmuir surface area,6785 m2 g−1).The possible halogen exchange and dehalogenation coupling mechanisms for this new catalytic process in PAF's synthesis are discussed in detail.The efficiency and universality of this innovative catalyst system have also been demonstrated in other PAFs'synthesis.This work provides a cheap,facile,and efficient method for scalable synthesis of PAFs and explores their application for high-pressure storage of Xe and Kr. 展开更多
关键词 adsorption carbon material nickel catalysis porous aromatic framework porous organic polymer
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Research advances of tetrahedral framework nucleic acid-based systems in biomedicine
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作者 Lihang Wang Mary Li Javier +5 位作者 Chunshan Luo Tingsheng Lu Shudan Yao Bing Qiu Yun Wang Yunfeng Lin 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第11期35-43,共9页
This article reviews the latest research advances of tetrahedral framework nucleic acid(t FNA)-based systems in their fabrication,modification,and the potential applications in biomedicine.TFNA arises from the synthes... This article reviews the latest research advances of tetrahedral framework nucleic acid(t FNA)-based systems in their fabrication,modification,and the potential applications in biomedicine.TFNA arises from the synthesis of four single-stranded DNA chains.Each chain contains brief sequences that complement those found in the other three,culminating in the creation of a pyramid-shaped nanostructure of approximately 10 nanometers in size.The first generation of t FNA demonstrates inherent compatibility with biological systems and the ability to permeate cell membrane effectively.These attributes translate into remarkable capabilities for regulating various cellular biological processes,fostering tissue regeneration,and modulating immune responses.The subsequent evolution of t FNA introduces enhanced adaptability and a relatively higher degree of biological stability.This advancement encompasses structural modifications,such as the addition of functional domains at the vertices or side arms,integration of low molecular weight pharmaceuticals,and the implementation of diverse strategies aimed at reversing multi-drug resistance in tumor cells or microorganisms.These augmentations empower t FNA-based systems to be utilized in different scenarios,thus broadening their potential applications in various biomedical fields. 展开更多
关键词 DNA nanomaterials Tetrahedral framework nucleic acid Drug delivery ANTIOXIDATION IMMUNOMODULATION Tissue regeneration Antitumor therapy
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Synthesis,structures,and properties of metal-organic frameworks based on bipyridyl ligands and isophthalic acid 被引量:1
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作者 HOU Jimin LI Mengyang +4 位作者 GONG Chunhua ZHANG Shaozhuang ZHAN Caihong XU Hao XIE Jingli 《无机化学学报》 北大核心 2025年第3期549-560,共12页
(2E,6E)-4-methyl-2,6-bis(pyridin-3-ylmethylene)cyclohexan-1-one(L_(1))and 4-methyl-2,6-bis[(E)-4-(pyridin-4-yl)benzylidene]cyclohexan-1-one(L_(2))were synthesized and combined with isophthalic acid(H_(2)IP),then under... (2E,6E)-4-methyl-2,6-bis(pyridin-3-ylmethylene)cyclohexan-1-one(L_(1))and 4-methyl-2,6-bis[(E)-4-(pyridin-4-yl)benzylidene]cyclohexan-1-one(L_(2))were synthesized and combined with isophthalic acid(H_(2)IP),then under solvothermal conditions,to react with transition metals achieving four novel metal-organic frameworks(MOFs):[Zn(IP)(L_(1))]_(n)(1),{[Cd(IP)(L_(1))]·H_(2)O}_(n)(2),{[Co(IP)(L_(1))]·H_(2)O}_(n)(3),and[Zn(IP)(L_(2))(H_(2)O)]_(n)(4).MOFs 1-4 have been characterized by single-crystal X-ray diffraction,powder X-ray diffraction,thermogravimetry,and elemental analysis.Single-crystal X-ray diffraction shows that MOF 1 crystallizes in the monoclinic crystal system with space group P2_(1)/n,and MOFs 2-4 belong to the triclinic system with the P1 space group.1-3 are 2D sheet structures,2 and 3 have similar structural characters,whereas 4 is a 1D chain structure.Furthermore,1-3 exhibited certain photocatalytic capability in the degradation of rhodamine B(Rh B)and pararosaniline hydrochloride(PH).4could be used as a heterogeneous catalyst for the Knoevenagel reaction starting with benzaldehyde derivative and malononitrile.4 could promote the reaction to achieve corresponding products in moderate yields within 3 h.Moreover,the catalyst exhibited recyclability for up to three cycles without significantly dropping its activity.A mechanism for MOF 4 catalyzed Knoevenagel condensation reaction of aromatic aldehyde and malononitrile has been initially proposed.CCDC:2356488,1;2356497,2;2356499,3;2356498,4. 展开更多
关键词 bipyridyl ligands metal⁃organic frameworks photocatalytic degradation Knoevenagel condensation
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Metal-organic framework-derived sulfur-doped iron-cobalt tannate nanorods for efficient oxygen evolution reaction performance 被引量:1
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作者 ZHAI Haoying WEN Lanzong +3 位作者 LIAO Wenjie LI Qin ZHOU Wenjun CAO Kun 《无机化学学报》 北大核心 2025年第5期1037-1048,共12页
Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nano... Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nanorods,which had many voids.The S-FeCoTA catalysts exhibited excellent electrochemical oxygen evolution reaction(OER)performance with a low overpotential of 273 mV at 10 mA·cm^(-2)and a small Tafel slope of 36 mV·dec^(-1)in 1 mol·L^(-1)KOH.The potential remained at 1.48 V(vs RHE)at 10 mA·cm^(-2)under continuous testing for 15 h,implying that S-FeCoTA had good stability.The Faraday efficiency of S-FeCoTA was 94%.The outstanding OER activity of S-FeCoTA is attributed to the synergistic effects among S,Fe,and Co,thus promoting electron transfer,reducing the reaction kinetic barrier,and enhancing the OER performance. 展开更多
关键词 hydrothermal method tannic acid metal‑organic framework ELECTROCATALYSIS oxygen evolution reaction
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Construction of iron manganese metal-organic framework-derived manganese ferrite/carbon-modified graphene composites toward broadband and efficient electromagnetic dissipation 被引量:2
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作者 Baohua Liu Shuai Liu +1 位作者 Zaigang Luo Ruiwen Shu 《International Journal of Minerals,Metallurgy and Materials》 2025年第3期546-555,共10页
The preparation of carbon-based electromagnetic wave(EMW)absorbers possessing thin matching thickness,wide absorption bandwidth,strong absorption intensity,and low filling ratio remains a huge challenge.Metal-organic ... The preparation of carbon-based electromagnetic wave(EMW)absorbers possessing thin matching thickness,wide absorption bandwidth,strong absorption intensity,and low filling ratio remains a huge challenge.Metal-organic frameworks(MOFs)are ideal self-sacrificing templates for the construction of carbon-based EMW absorbers.In this work,bimetallic FeMn-MOF-derived MnFe_(2)O_(4)/C/graphene composites were fabricated via a two-step route of solvothermal reaction and the following pyrolysis treatment.The results re-veal the evolution of the microscopic morphology of carbon skeletons from loofah-like to octahedral and then to polyhedron and pomegran-ate after the adjustment of the Fe^(3+)to Mn^(2+)molar ratio.Furthermore,at the Fe^(3+)to Mn^(2+)molar ratio of 2:1,the obtained MnFe_(2)O_(4)/C/graphene composite exhibited the highest EMW absorption capacity.Specifically,a minimum reflection loss of-72.7 dB and a max-imum effective absorption bandwidth of 5.1 GHz were achieved at a low filling ratio of 10wt%.In addition,the possible EMW absorp-tion mechanism of MnFe_(2)O_(4)/C/graphene composites was proposed.Therefore,the results of this work will contribute to the construction of broadband and efficient carbon-based EMW absorbers derived from MOFs. 展开更多
关键词 metal-organic frameworks GRAPHENE magnetic composites morphology regulation electromagnetic dissipation
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Perspectives on metal-organic framework-derived microwave absorption materials 被引量:2
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作者 Meng-Qi Wang Mao-Sheng Cao 《Journal of Materials Science & Technology》 2025年第11期37-52,共16页
Exploring efficient microwave absorbing materials(MAMs)has gradually become a hot topic in recent years because it is crucial in both civil and military fields.Metal-organic framework(MOF)has great potential due to it... Exploring efficient microwave absorbing materials(MAMs)has gradually become a hot topic in recent years because it is crucial in both civil and military fields.Metal-organic framework(MOF)has great potential due to its unique composition and bonding mode,which has advantages such as large specific surface area,high porosity,adjustable structure,and designable composition.Herein,MOF-derived MAMs are highlighted based on morphology and structure.The synthesis strategies of MOF-derived MAMs of different dimensions are discussed.On this basis,the structure-activity relationships can be deeply explored through the precise control of material structure and property by atomic engineering.Finally,perspectives are given for the existing problems of MOF-derived MAMs,which will open a new horizon and promote the development of MAMs. 展开更多
关键词 Metal-organic framework Atomic engineering Microwave absorption
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Superelastic and ultralight covalent organic framework composite aerogels modified with different functional groups for ultrafast adsorbing organic pollutants in water 被引量:1
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作者 Shiyan Ai Yaning Xu +3 位作者 Hui Zhou Ziwei Cui Tiantian Wu Dan Tian 《Chinese Chemical Letters》 2025年第10期478-487,共10页
Covalent organic frameworks(COFs)have great potential as adsorbents due to their customizable functionality,low density and high porosity.However,COFs powder exists with poor processing and recycling performance.Moreo... Covalent organic frameworks(COFs)have great potential as adsorbents due to their customizable functionality,low density and high porosity.However,COFs powder exists with poor processing and recycling performance.Moreover,due to the accumulation of COFs nanoparticles,it is not conducive to the full utilization of their surface functional groups.Currently,the strategy of COFs assembling into aerogel can be a good solution to this problem.Herein,we successfully synthesize composite aerogels(CSR)by in-situ self-assembly of two-dimensional COFs and graphene based on crosslinking of sodium alginate.Sodium alginate in the composite improves the mechanical properties of the aerogel,and graphene provides a template for the in-situ growth of COFs.Impressively,CSR aerogels with different COFs and sizes can be prepared by changing the moiety of the ligand and modulating the addition amount of COFs.The prepared CSR aerogels exhibit porous,low density,good processability and good mechanical properties.Among them,the density of CSR-N-1.6 is only 5 mg/cm3,which is the lowest density among the reported COF aerogels so far.Due to these remarkable properties,CSR aerogels perform excellent adsorption and recycling properties for the efficient and rapid removal of organic pollutants(organic dyes and antibiotics)from polluted water.In addition,it is also possible to visually recognize the presence of antibiotics by fluorescence detection.This work not only provides a new strategy for synthesizing COF aerogels,but also accelerates the practical application of COF aerogels and contributes to environmental remediation. 展开更多
关键词 Covalent organic frameworks GRAPHENE AEROGELS ADSORPTION Sewage treatment
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Controllable synthesis of hydrogen-bonded organic framework encapsulated enzyme for continuous production of chiral hydroxybutyric acid in a two-stage cascade microreactor 被引量:1
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作者 Danyang Zhao Qiangqiang Xue +1 位作者 Yujun Wang Guangsheng Luo 《Chinese Journal of Chemical Engineering》 2025年第1期175-184,共10页
Constructing a framework carrier to stabilize protein conformation,induce high embedding efficiency,and acquire low mass-transfer resistance is an urgent issue in the development of immobilized enzymes.Hydrogen-bonded... Constructing a framework carrier to stabilize protein conformation,induce high embedding efficiency,and acquire low mass-transfer resistance is an urgent issue in the development of immobilized enzymes.Hydrogen-bonded organic frameworks(HOFs)have promising application potential for embedding enzymes.In fact,no metal involvement is required,and HOFs exhibit superior biocompatibility,and free access to substrates in mesoporous channels.Herein,a facile in situ growth approach was proposed for the self-assembly of alcohol dehydrogenase encapsulated in HOF.The micron-scale bio-catalytic composite was rapidly synthesized under mild conditions(aqueous phase and ambient temperature)with a controllable embedding rate.The high crystallinity and periodic arrangement channels of HOF were preserved at a high enzyme encapsulation efficiency of 59%.This bio-composite improved the tolerance of the enzyme to the acid-base environment and retained 81%of its initial activity after five cycles of batch hydrogenation involving NADH coenzyme.Based on this controllably synthesized bio-catalytic material and a common lipase,we further developed a two-stage cascade microchemical system and achieved the continuous production of chiral hydroxybutyric acid(R-3-HBA). 展开更多
关键词 Hydrogen-bonded organic framework Immobilized enzyme Synthesis Chiral hydroxycarboxylic acid BIOCATALYSIS Nanostructure
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Radiation reduction modification of sp^(2) carbon-conjugated covalent organic frameworks for enhanced photocatalytic chromium(Ⅵ) removal 被引量:1
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作者 Shouchao Zhong Yue Wang +6 位作者 Mingshu Xie Yiqian Wu Jiuqiang Li Jing Peng Liyong Yuan Maolin Zhai Weiqun Shi 《Chinese Chemical Letters》 2025年第5期277-282,共6页
A sp^(2) carbon-conjugated covalent organic framework (BDATN) was modified through γ-ray radiation reduction and subsequent acidification with hydrochloric acid to yield a novel functional COF (named rBDATN-HCl) for ... A sp^(2) carbon-conjugated covalent organic framework (BDATN) was modified through γ-ray radiation reduction and subsequent acidification with hydrochloric acid to yield a novel functional COF (named rBDATN-HCl) for Cr(Ⅵ) removal.The morphology and structure of rBDATN-HCl were analyzed and identified by SEM,FTIR,XRD and solid-state13C NMR.It is found that the active functional groups,such as hydroxyl and amide,were introduced into BDATN after radiation reduction and acidification.The prepared rBDATN-HCl demonstrates a photocatalytic reduction removal rate of Cr(Ⅵ) above 99%after 60min of illumination with a solid-liquid ratio of 0.5 mg/mL,showing outstanding performance,which is attributed to the increase of dispersibility and adsorption sites of r BDATN-HCl.In comparison to the cBDATN-HCl synthesized with chemical reduction,rBDATN-HCl exhibits a better photoreduction performance for Cr(Ⅵ),demonstrating the advantages of radiation preparation of rBDATN-HCl.It is expected that more functionalized sp^(2) carbon-conjugated COFs could be obtained by this radiation-induced reduction strategy. 展开更多
关键词 Covalent organic framework Gamma radiation Photocatalytic reduction CHROMIUM Water purification
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Detailed oil-source correlation within the sequence and sedimentary framework in the Fushan Depression,Beibuwan Basin,South China Sea 被引量:1
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作者 Xin Wang Mei-Jun Li +3 位作者 Yang Shi Hao Guo Bang Zeng Xi He 《Petroleum Science》 2025年第1期90-109,共20页
The Fushan Depression is one of the petroliferous depressions in the Beibuwan Basin,South China Sea.Previous studies have preliminarily explored the origin and source of crude oils in some areas of this depression.Nev... The Fushan Depression is one of the petroliferous depressions in the Beibuwan Basin,South China Sea.Previous studies have preliminarily explored the origin and source of crude oils in some areas of this depression.Nevertheless,no systematic investigations on the classification and origin of oils and hy-drocarbon migration processes have been made for the entire petroleum system in this depression,which has significantly hindered the hydrocarbon exploration in the region.A total of 32 mudstone and 58 oil samples from the Fushan Depression were analyzed to definite the detailed oil-source correlation within the sequence and sedimentary framework.The organic matter of third member of Paleogene Liushagang Formation(Els(3))source rocks,both deltaic and lacustrine mudstone,are algal-dominated with high abundance of C_(23)tricyclic terpane and C_(30)4-methylsteranes.The deltaic source rocks occur-ring in the first member(Els_(1))and second member(Els_(2))of the Paleogene Liushagang Formation are characterized by high abundance of C_(19+20)tricyclic terpane and oleanane,reflecting a more terrestrial plants contribution.While lacustrine source rocks of Els_(1)and Els_(2)display the reduced input of terrige-nous organic matter with relatively low abundance of C 19+20 tricyclic terpane and oleanane.Three types of oils were identified by their biomarker compositions in this study.Most of the oils discovered in the Huachang and Bailian Els_(1)reservoir belong to group A and were derived from lacustrine source rocks of Els_(1)and Els_(2).Group B oils are found within the Els_(1)and Els_(2)reservoirs,showing a close relation to the deltaic source rocks of Els_(1)and Els_(2),respectively.Group C oils,occurring in the Els3 reservoirs,have a good affinity with the Els3 source rocks.The spatial distribution and accumulation of different groups of oils are mainly controlled by the sedimentary facies and specific structural conditions.The Els_(2)reservoir in the Yong'an area belonging to Group B oil,are adjacent to the source kitchen and could be considered as the favorable exploration area in the future. 展开更多
关键词 Oil-source correlation Sequence stratigraphic framework Biomarkers Fushan depression South China Sea
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