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A visibly transparent radiative cooling film with self-cleaning function produced by solution processing 被引量:1
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作者 Guoliang Chen Yaming Wang +6 位作者 Jun Qiu Jianyun Cao Yongchun Zou Shuqi Wang Jiahu Ouyang Dechang Jia Yu Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第31期76-84,共9页
Daylighting structures,including solar cells and building windows,utilize sunlight whilst suffering from undesired solar heat and outdoor dust contamination.A radiative cooling system that is transparent to sunlight a... Daylighting structures,including solar cells and building windows,utilize sunlight whilst suffering from undesired solar heat and outdoor dust contamination.A radiative cooling system that is transparent to sunlight and has a superhydrophobic surface would cool and clean the daylighting structures in a sustainable manner.However,the majority of the current daytime radiative cooling systems were designed to fully reflect the incident sunlight to maximize the cooling power.In this work,we optimized both the sunlight transmission and infrared thermal irradiation by modeling the size-dependent scattering and absorption of light by SiO_(2)spheres embedded in a polymer matrix,we found that the use of nanospheres(20 nm)enabled both high sunlight transmittance(>90%)and infrared emissivity(-0.85).This theoretical prediction was confirmed by experimental measurements of a solution-processed nanocomposite film.When coated on a solar cell,the as-prepared film not only preserved the power conversion efficiency of the cell(14.71%,uncoated cell has an efficiency of 14.79%)but also radiatively cooled the cell by up to 5℃under direct sunlight.This reduction of the operating temperature of the solar cell further enhanced its electrical power output,evidenced by an increase in the equilibrium temperature of the LED load by about 14℃.The nanoscale textured surface formed by the nanospheres further led to superhydrophobicity and thus excellent self-cleaning performance(efficient removal of dust by wind and/or water droplets). 展开更多
关键词 Nanocomposite film Radiative cooling visibly transparent SELF-CLEANING
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Visible light photocatalytic enhanced heterogeneous cobalt catalyzed peroxymonosulfate synergistic process to degradation atrazine:Efficiency,influencing factors,by-products removal and mechanism
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作者 Qingkong Chen Jieyu Xia +3 位作者 Fengjun Liu Jianping Fan Peng Yan Mika Sillanpää 《Journal of Environmental Sciences》 2026年第1期166-177,共12页
This study developed a novel heterogeneous Vis-Photo+Fenton-like system by integrating visible-light-responsive Co_(3)O_(4)/TiO_(2) photocatalysis with peroxymonosulfate(PMS)activation for efficient atrazine(ATZ)degra... This study developed a novel heterogeneous Vis-Photo+Fenton-like system by integrating visible-light-responsive Co_(3)O_(4)/TiO_(2) photocatalysis with peroxymonosulfate(PMS)activation for efficient atrazine(ATZ)degradation.The synergistic process achieved complete ATZ removal within 60 min under near-neutral pH(6.9),outperform-ing individual Fenton-like(39%)and photocatalytic(24%)processes.Key factors influencing the degradation efficiency included light sources(UV>visible),pH(optimal at 6.9),catalyst dosage(0.01 g Co_(3)O_(4)/TiO_(2)),and PMS:ATZ molar ratio(1:2).The system exhibited a synergistic coefficient of 5.03(degradation)and 1.97(miner-alization),attributed to enhanced radical generation and accelerated Co^(3+)/Co^(2+)redox cycling through photoin-duced electron transfer.Intermediate analysis revealed dealkylation,dechlorination,and oxidation pathways,with reduced toxicity of by-products(e.g.,CEAT,CIAT)confirmed by ecotoxicity assessments.The mineralization efficiency(Vis-Photo+Fenton-like)reached 83.1%,significantly higher than that of standalone processes(Fenton-like:43.2%;photocatalysis:30.5%).The catalyst demonstrated excellent stability(nearly 90%recov-ery,<1μg/L Co leaching)and practical applicability.This study provides an efficient,sludge-free,and solar-compatible strategy for eliminating persistent herbicides in water treatment. 展开更多
关键词 Synergistic effect Sulfate radical FENTON-LIKE PHOTOCATALYSIS Visible light Atrazine(ATZ)
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FDEFusion:End-to-End Infrared and Visible Image Fusion Method Based on Frequency Decomposition and Enhancement
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作者 Ming Chen Guoqiang Ma +3 位作者 Ping Qi Fucheng Wang Lin Shen Xiaoya Pi 《Computers, Materials & Continua》 2026年第4期817-839,共23页
In the image fusion field,fusing infrared images(IRIs)and visible images(VIs)excelled is a key area.The differences between IRIs and VIs make it challenging to fuse both types into a high-quality image.Accordingly,eff... In the image fusion field,fusing infrared images(IRIs)and visible images(VIs)excelled is a key area.The differences between IRIs and VIs make it challenging to fuse both types into a high-quality image.Accordingly,efficiently combining the advantages of both images while overcoming their shortcomings is necessary.To handle this challenge,we developed an end-to-end IRI andVI fusionmethod based on frequency decomposition and enhancement.By applying concepts from frequency domain analysis,we used the layering mechanism to better capture the salient thermal targets from the IRIs and the rich textural information from the VIs,respectively,significantly boosting the image fusion quality and effectiveness.In addition,the backbone network combined Restormer Blocks and Dense Blocks;Restormer blocks utilize global attention to extract shallow features.Meanwhile,Dense Blocks ensure the integration between shallow and deep features,thereby avoiding the loss of shallow attributes.Extensive experiments on TNO and MSRS datasets demonstrated that the suggested method achieved state-of-the-art(SOTA)performance in various metrics:Entropy(EN),Mutual Information(MI),Standard Deviation(SD),The Structural Similarity Index Measure(SSIM),Fusion quality(Qabf),MI of the pixel(FMI_(pixel)),and modified Visual Information Fidelity(VIF_(m)). 展开更多
关键词 Infrared images visible images frequency decomposition restormer blocks global attention
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PMCFusion:A Parallel Multi-Dimensional Complementary Network for Infrared and Visible Image Fusion
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作者 Xu Tao Qiang Xiao +1 位作者 Zhaoqi Jin Hao Li 《Computers, Materials & Continua》 2026年第2期1649-1666,共18页
Image fusion technology aims to generate a more informative single image by integrating complementary information from multi-modal images.Despite the significant progress of deep learning-based fusion methods,existing... Image fusion technology aims to generate a more informative single image by integrating complementary information from multi-modal images.Despite the significant progress of deep learning-based fusion methods,existing algorithms are often limited to single or dual-dimensional feature interactions,thus struggling to fully exploit the profound complementarity between multi-modal images.To address this,this paper proposes a parallel multidimensional complementary fusion network,termed PMCFusion,for the task of infrared and visible image fusion.The core of this method is its unique parallel three-branch fusion module,PTFM,which pioneers the parallel synergistic perception and efficient integration of three distinct dimensions:spatial uncorrelation,channel-wise disparity,and frequency-domain complementarity.Leveraging meticulously designed cross-dimensional attention interactions,PTFM can selectively enhance multi-dimensional features to achieve deep complementarity.Furthermore,to enhance the detail clarity and structural integrity of the fused image,we have designed a dedicated multi-scale high-frequency detail enhancement module,HFDEM.It effectively improves the clarity of the fused image by actively extracting,enhancing,and injecting high-frequency components in a residual manner.The overall model employs a multi-scale architecture and is constrained by corresponding loss functions to ensure efficient and robust fusion across different resolutions.Extensive experimental results demonstrate that the proposed method significantly outperforms current state-of-the-art fusion algorithms in both subjective visual effects and objective evaluation metrics. 展开更多
关键词 Infrared and visible image fusion deep learning parallelmulti-dimensional attention mechanism detail enhancement
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Chinese Rural Women's Social Media Use: An Empirical Study Adopting the Technology Acceptance Model
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作者 Zhang Hui Mahadevan Krishnan 《Contemporary Social Sciences》 2026年第1期104-122,共19页
Given the growing importance of social media in digital rural development, this study systematically investigated the influence pathways of social media use among rural women in China, drawing on the Technology Accept... Given the growing importance of social media in digital rural development, this study systematically investigated the influence pathways of social media use among rural women in China, drawing on the Technology Acceptance Model(TAM). Employing quantitative research methods, the study conducted empirical tests based on 367 valid questionnaires using Partial Least Squares Structural Equation Modeling(PLS-SEM) via SmartPLS 4.0 software. Results indicate that significant associations exist between perceived ease of use, perceived usefulness, attitudes toward use, behavioral intention, and actual usage behavior. Specifically, the study finds that rural women's perceived ease of use of social media has a significant and positive influence on both perceived usefulness and attitudes toward use. Perceived usefulness further significantly promotes attitudes toward use and behavioral intention. Moreover, positive attitudes toward usage and strong behavioral intentions were effectively converted into actual social media usage behaviors. This study not only validates the applicability and explanatory power of the TAM model in understanding the digital behavior of Chinese rural women but also provides quantitative evidence for how social media enhances their “digital visibility.” These findings offer practical insights for governments and platform providers to optimize user experiences and strengthen digital skills training. Despite its limitations, including a cross-sectional design and a regional sample, this research holds significant theoretical and practical implications. 展开更多
关键词 Chinese rural women social media Technology Acceptance Model(TAM) digital visibility
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A Multi-Scale Cross-Band Defense System Integrating Decoupled Visible,Dynamic Infrared Camouflage and Electromagnetic Shielding
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作者 Junlin Liu Shujuan Tan +4 位作者 Xinrui Yang Jiajie Zhu Xin Yan Tianyu Chen Guangbin Ji 《Nano-Micro Letters》 2026年第4期335-352,共18页
Cross-band camouflage technology is a critical necessity,enabling personnel and equipment to evade detection across evolving surveillance systems,thereby enhancing survivability and mission success.Herein,this work de... Cross-band camouflage technology is a critical necessity,enabling personnel and equipment to evade detection across evolving surveillance systems,thereby enhancing survivability and mission success.Herein,this work develops a layer-structured composite system based on carbon nanotube(CNT)film comprising ionic liquid(IL)interlayer for infrared(IR)modulation and surface-engineered Cu_(2)O nanoparticles for visible camouflage.The CNT/IL/CNT architecture enables reversible IR emissivity switching(Δε≈0.55)through electrically driven ion intercalation/deintercalation within 2 s,while spray-coated Cu_(2)O nanoparticles(100~400 nm diameter)on the top CNT film layer generate rich structure colors with 90%IR transmittance.This spectral-decoupling design overcomes the traditional trade-off between color visibility and IR transmittance observed in pigment-based systems.Remarkably,due to physical interface coupling,the Cu_(2)O-coated layer-structured system maintains exceptional electrical conductivity,enabling simultaneous electromagnetic interference shielding and electrothermal energy conversion.The integrated system demonstrates long-term operational stability.By unifying visible-IR camouflage,electromagnetic protection,and energy management in a lightweight platform,this work provides an important paradigm for cross-band camouflage technologies. 展开更多
关键词 Visible camouflage Adaptive IR camouflage Cu_(2)O/CNT composite film Electrothermal energy conversion EMI shielding
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Chaotic dynamics of Pr^(3+)/Yb^(3+)-doped all-fiber up-conversion visible fiber laser
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作者 Yisong Li Yueling Hao +4 位作者 Juanfen Wang Xiaohui Chen Shengxiang Chen Chao Zhou Lingzhen Yang 《Chinese Physics B》 2026年第1期492-496,共5页
We investigate theoretically and experimentally the chaotic dynamics of visible-wavelength all-fiber ring laser.The100-m 630 HP fibers are used to ensure high non-linearity.A 4-m Pr^(3+)/Yb^(3+)-co-doped ZBLAN fiber p... We investigate theoretically and experimentally the chaotic dynamics of visible-wavelength all-fiber ring laser.The100-m 630 HP fibers are used to ensure high non-linearity.A 4-m Pr^(3+)/Yb^(3+)-co-doped ZBLAN fiber provides the gain.The chaotic laser was pumped by the laser diodes with the maximum power of 150 mW at the wavelength of 850 nm.The peak fluorescence spectrum of Pr^(3+)/Yb^(3+)-co-doped ZBLAN fiber at the wavelength of 635 nm shows that the visiblewavelength fiber laser can be achieved by synergistic energy transfer between Pr~(3+)and Yb^(3+)ions.The chaotic fiber laser is generated by adjusting the pump power,polarization controller and the auto-correlation,permutation entropy,skewness,and kurtosis were used to analyze the characteristics of chaotic laser.The noise-like time series and delta-like auto-correlation curve indicate the chaotic output.The complexity and randomness of time series are analyzed by the permutation entropy,skewness,and kurtosis.The result shows that chaotic dynamics is stable when the pump power exceeds a certain value.The visible chaotic all-fiber laser has high stability and can be applied for real-time monitoring and sensing.We believe that this approach may also be feasible for other materials for emission in the visible range. 展开更多
关键词 chaotic lasers visible fiber laser randomness Pr^(3+)/Yb^(3+)doped fiber
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Photoinduced Electron Transfer-Driven Reductive Coupling ofα-Keto Esters for Efficient Carbon-Carbon Bond Construction
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作者 CHEN Di WANG Le 《Journal of Donghua University(English Edition)》 2026年第1期1-9,共9页
Catalytic reduction reactions using isopropanol(IPA)as a transfer hydrogenating agent are gaining significant attention due to the low cost and large-scale production of IPA.Traditional methods for carbon-carbon(C—C)... Catalytic reduction reactions using isopropanol(IPA)as a transfer hydrogenating agent are gaining significant attention due to the low cost and large-scale production of IPA.Traditional methods for carbon-carbon(C—C)bond construction often rely on expensive and scarce transition metal catalysts,raising concerns about sustainability and environmental impact.To address these challenges,we develop a bifunctional photocatalyst,phloroglucinol carbon quantum dot(PG-CQD).It facilitates catalytic transfer hydrogenation(CTH)with IPA as the hydrogen donor.PG-CQDs exhibit both dehydrogenation and reduction activities,enabling the formation of vicinal diols under mild conditions with visible light irradiation.We propose a CTH mechanism that has been successfully validated through experiments.The catalytic system demonstrates remarkable versatility,enabling the synthesis of various vicinal diols from diverseα-keto ester substrates with good or excellent yields.These findings offer a sustainable synthetic strategy that aligns with green chemistry principles and establish a promising pathway for the development of environmentally benign and energy-efficient organic transformations. 展开更多
关键词 carbon-carbon(C-C)bond reductive coupling catalytic transfer hydrogenation(CTH) visible light carbon quantum dot(CQD) isopropanol(IPA)
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Visible Light-Promoted Aerobic Oxo-azidation of Alkenyl Silanes 被引量:1
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作者 Tan Yan Ying Jiale +1 位作者 Yu Bing Lu Zhan 《有机化学》 北大核心 2025年第5期1684-1690,共7页
A visible-light-enabled method for the synthesis ofα-azidoketones has been developed via oxo-azidation of alkenyl silanes with trimethylsilylazide and molecular oxygen under mild conditions.The reaction could be carr... A visible-light-enabled method for the synthesis ofα-azidoketones has been developed via oxo-azidation of alkenyl silanes with trimethylsilylazide and molecular oxygen under mild conditions.The reaction could be carried out in gram scale.Various radical sources,including trifluoromethyl radical,thiocyanate radical,bromide radical,chlorine radical could partici-pate effectively instead of azide radical in the reaction. 展开更多
关键词 visible light catalysis aerobic oxidation alkenyl silanes organic azides
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Efficient chlorination reaction of Pt/RuO_(2)/g-C_(3)N_(4)under visible light irradiation for simultaneous removal of ammonia and bacteria from mariculture wastewater 被引量:1
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作者 Yizhan Zhang Min Zhao +2 位作者 Yida Huang Yan-Ling Hu Lei Wang 《Journal of Environmental Sciences》 2025年第4期490-502,共13页
The removal of ammonia nitrogen(NH_(4)^(+)-N)and bacteria from aquaculture wastewater holds paramount ecological and production significance.In this study,Pt/RuO_(2)/g-C_(3)N_(4)photocatalysts were prepared by deposit... The removal of ammonia nitrogen(NH_(4)^(+)-N)and bacteria from aquaculture wastewater holds paramount ecological and production significance.In this study,Pt/RuO_(2)/g-C_(3)N_(4)photocatalysts were prepared by depositing Pt and RuO_(2)particles onto g-C_(3)N_(4).The physicochemical properties of photocatalysts were explored by X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM),X-ray diffraction(XRD),and UV–vis diffuse reflectance spectrometer(UV–vis DRS).The photocatalysts were then applied to the removal of both NH_(4)^(+)-N and bacteria from simulated mariculture wastewater.The results clarified that the removals of both NH_(4)^(+)-N and bacteria were in the sequence of g-C_(3)N_(4)<RuO_(2)/g-C_(3)N_(4)<Pt/g-C_(3)N_(4)<Pt/RuO_(2)/g-C_(3)N_(4).This magnificent photocatalytic ability of Pt/RuO_(2)/g-C_(3)N_(4)can be interpreted by the transfer of holes from g-C_(3)N_(4)to RuO_(2)to facilitate the in situ generation of HClO from Cl^(−)in wastewater,while Pt extracts photogenerated electrons for H_(2)formation to enhance the reaction.The removal of NH_(4)^(+)-N and disinfection effect were more pronounced in simulated seawater than in purewater.The removal efficiency ofNH_(4)^(+)-N increases with an increase in pH of wastewater,while the bactericidal effect was more significant under a lower pH in a pH range of 6–9.In actual seawater aquaculture wastewater,Pt/RuO_(2)/g-C_(3)N_(4)still exhibits effective removal efficiency of NH_(4)^(+)-N and bactericidal performance under sunlight.This study provides an alternative avenue for removement of NH_(4)^(+)-N and bacteria from saline waters under sunlight. 展开更多
关键词 PHOTOCATALYSIS Mariculture wastewater Ammonia nitrogen Visible light irradiation Microbial inactivation
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Development of Palygorskite-CaIn_(2)S_(4) composite for rapid Cr(Ⅵ) reduction under visible light 被引量:1
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作者 Yuanyuan Wang Shijun Jia +3 位作者 Shiqiang Ding Wenyan Zhang Rui Shu Yingfei Hu 《Journal of Environmental Sciences》 2025年第10期562-575,共14页
Using natural minerals to eliminate harmful Cr(Ⅵ)under sustainable sunshine has significant potential.Herein,Palygorskite nanorods were utilized as carriers for the in-situ synthesis of CaIn_(2)S_(4) photocatalysts t... Using natural minerals to eliminate harmful Cr(Ⅵ)under sustainable sunshine has significant potential.Herein,Palygorskite nanorods were utilized as carriers for the in-situ synthesis of CaIn_(2)S_(4) photocatalysts through a simple one-pot thermal process,enabling the efficient reduction of Cr(Ⅵ).With a Palygorskite to CaIn_(2)S_(4) mass ratio of 5%,the conversion rate of Cr(Ⅵ)reached 98%after 60min of visible-light exposure,with a remarkable reaction rate of 0.0633 min^(-1).The effective integration of CaIn_(2)S_(4) with Palygorskite led to a more uniform dispersion of CaIn_(2)S_(4),exposing more reactive sites.Moreover,the establishment of a heterojunction between CaIn_(2)S_(4) and Palygorskite facilitated the transport of photogenerated electrons from CaIn_(2)S_(4),enhancing the efficiency of charge separation.These factors contribute to the improved photocatalytic performance.Additionally,the developed composite photocatalysts demonstrated excellent stability under light exposure and could be reused efficiently.Trapping tests on active substances revealed that e-played key roles in the Cr(Ⅵ)reduction.This research suggests the potential of using natural minerals to fabricate composite photocatalysts capable of effectively removing pollutants from the environment using solar energy. 展开更多
关键词 Cr(Ⅵ)reduction Visible light PALYGORSKITE CaIn_(2)S_(4)
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A magnetic N-doped graphene photocatalyst for fast tetracycline degradation
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作者 ZHANG Ze-liang ZHAO Nan +3 位作者 LI Ru-yi ZHANG Yi MA Can-liang FENG Si-si 《新型炭材料(中英文)》 北大核心 2025年第6期1377-1390,I0060-I0065,共20页
A novel nitrogen-doped graphene(NG)supporting magnetic nanoparticles(Fe and Fe_(3)C)was synthesized from g-C_(3)N_(4)and Fe(C_(5)H_(5))_(2).When used as a photocatalyst exposed to visible light,the material was excell... A novel nitrogen-doped graphene(NG)supporting magnetic nanoparticles(Fe and Fe_(3)C)was synthesized from g-C_(3)N_(4)and Fe(C_(5)H_(5))_(2).When used as a photocatalyst exposed to visible light,the material was excellent in degrading tetracycline(TC)in aqueous solutions.Scanning electron microscopy indicated that it had a folded sheet structure,with numerous nanoparticles observed on graphene sheets.Raman spectroscopy confirmed the presence of significant defects in the material,which suppressed the recombination of photogenerated electron-hole pairs.The performance and degradation mechanism of the photocatalyst was verified using a series of optical and electrochemical experiments and theoretical calculations.The degradation efficiency of the catalyst for TC was as high as 97.1%in 120 min under visible light irradiation,which is superior to other reported catalysts.A mechanism study showed that TC is rapidly degraded into CO_(2),H_(2)O and other small inorganic molecules,with holes(h^(+))serving as the primary driving force.The catalyst had an outstanding stability and reusability,and could be easily recovered using an external magnetic field. 展开更多
关键词 MAGNETIC PHOTOCATALYST Visible light DEGRADATION TETRACYCLINE
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BDMFuse:Multi-scale network fusion for infrared and visible images based on base and detail features
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作者 SI Hai-Ping ZHAO Wen-Rui +4 位作者 LI Ting-Ting LI Fei-Tao Fernando Bacao SUN Chang-Xia LI Yan-Ling 《红外与毫米波学报》 北大核心 2025年第2期289-298,共10页
The fusion of infrared and visible images should emphasize the salient targets in the infrared image while preserving the textural details of the visible images.To meet these requirements,an autoencoder-based method f... The fusion of infrared and visible images should emphasize the salient targets in the infrared image while preserving the textural details of the visible images.To meet these requirements,an autoencoder-based method for infrared and visible image fusion is proposed.The encoder designed according to the optimization objective consists of a base encoder and a detail encoder,which is used to extract low-frequency and high-frequency information from the image.This extraction may lead to some information not being captured,so a compensation encoder is proposed to supplement the missing information.Multi-scale decomposition is also employed to extract image features more comprehensively.The decoder combines low-frequency,high-frequency and supplementary information to obtain multi-scale features.Subsequently,the attention strategy and fusion module are introduced to perform multi-scale fusion for image reconstruction.Experimental results on three datasets show that the fused images generated by this network effectively retain salient targets while being more consistent with human visual perception. 展开更多
关键词 infrared image visible image image fusion encoder-decoder multi-scale features
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Photoinduced Nickel-Catalyzed Reductive Heck Reaction
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作者 Liu Junjie Zhao Hongping +2 位作者 Hu Yuanyuan Wang Hengxin Yuan Weiming 《有机化学》 北大核心 2025年第5期1691-1697,共7页
An efficient visible-light induced nickel-catalyzed reductive Heck reaction of alkenes by using mild organic reductant Hantzsch ester(HEH)instead of traditional metal reductants or hydride reagents was developed.The r... An efficient visible-light induced nickel-catalyzed reductive Heck reaction of alkenes by using mild organic reductant Hantzsch ester(HEH)instead of traditional metal reductants or hydride reagents was developed.The reductive hydroarylation of acrylates with aryl halides was successfully achieved without requiring exogenous photoredox catalysts.This reaction is highlighted by the simple and mild conditions,good functional group tolerance,thus providing a complementary approach for alkenes reductive Heck reaction. 展开更多
关键词 NICKEL reductive Heck reaction visible light organic reductant alken
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Cyclization of N-(2-Ethynylphenyl)acrylamides for the Synthesis of Heteropolycyclic Compounds
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作者 Dong Daoqing Wang Yimeng +7 位作者 Zhu Gengning Wang Yanli Yu Shuguang Liu Juan Feng Jianxin Xu Xinming Yan Shiqiang Wang Zuli 《有机化学》 北大核心 2025年第10期3741-3754,共14页
N-(2-Ethynylphenyl)acrylamides have emerged as key intermediates for the synthesis of complex heteropolycyclic compounds.The recent advances focus on the tandem cyclization involving these precursors,among which forma... N-(2-Ethynylphenyl)acrylamides have emerged as key intermediates for the synthesis of complex heteropolycyclic compounds.The recent advances focus on the tandem cyclization involving these precursors,among which formation of fused six/N-three,six/five(N,S,O),and six/six-membered rings are highlighted.Nitrogen,sulfur,and oxygen incorporations into five-membered rings provide efficient routes to bioactive polycyclic molecules.These cyclization reactions exhibit excellent atom economy,high efficiency,and good functional group compatibility.Furthermore,novel catalytic systems and photochemical strategies also expand the synthetic applications of these precursors.Taken together,these advancements offer versatile tools for the synthesis of intricate heterocyclic scaffolds with broad applications in organic and medicinal chemistry. 展开更多
关键词 CYCLIZATION heteropolycyclic compounds N-(2-ethynylphenyl)acrylamides RADICAL visible light
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Na and O Co-doped Carbon Nitride for Efficient Photocatalytic Hydrogen Evolution
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作者 CHEN Libo SHENG Ying +3 位作者 WU Ming SONG Jiling JIAN Jian SONG Erhong 《无机材料学报》 北大核心 2025年第5期552-560,I0011,I0012,共11页
Elemental doping is an effective strategy for tuning the band structure of graphite carbon nitride(CN)to enhance its photocatalytic performance.In this study,sodium(Na)and oxygen(O)co-doped carbon nitride(Na/O-CN_(x),... Elemental doping is an effective strategy for tuning the band structure of graphite carbon nitride(CN)to enhance its photocatalytic performance.In this study,sodium(Na)and oxygen(O)co-doped carbon nitride(Na/O-CN_(x),x=1.0,2.0,3.0,4.0)was synthesized via solid-phase reaction of sodium citrate(NaCA)and pure CN powder in the Teflon-sealed autoclave under air conditions at 180℃.Surface area of Na/O-CN_(3.0) is measured to be 18.8 m^(2)/g,increasing by 60.7%compared to that of pure CN(11.7 m^(2)/g).Bandgap energy of Na/O-CN_(3.0) is determined to be 2.68 eV,marginally lower than that of pure CN(2.70 eV),thereby enhancing its capacity for sunlight absorption.Meanwhile,the incorporation of Na and O atoms into Na/O-CN_(x) is found to effectively reduce recombination rates of photogenerated electron-hole pairs.As a result,Na/O-CN_(x) samples exhibit markedly enhanced photocatalytic hydrogen evolution activity under visible light irradiation.Notably,the optimal Na/O-CN_(3.0) sample achieves a photocatalytic hydrogen production rate of 103.2μmol·g^(–1)·h^(–1),which is 8.2 times greater than that of pure CN(11.2μmol·g^(–1)·h^(–1)).Furthermore,a series of Na/O-CN_(x)-yO_(2)(y=0,20%,40%,60%,80%,100%)samples were prepared by modulating the oxygen content within reaction atmosphere.The catalytic performance evaluations reveal that the incorporation of both Na and O atoms in Na/O-CN_(3.0) enhances photocatalytic activity.This study also introduces novel methodologies for synthesis of metal atom-doped CN materials at lower temperature,highlighting the synergistic effect of Na and O atoms in photocatalytic hydrogen production of Na/O-CN_(x) samples. 展开更多
关键词 Na and O co-doped carbon nitride synergistic effect visible light photocatalytic hydrogen evolution
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Band gap regulation of MIL-101(Fe)via pyrazine-based ligands substitution for enhanced visible-light adsorption and its photo-Fenton-like application
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作者 Zongchen Li Jian Lu +3 位作者 Renjie Pan Qi Fu Tian-Yang Zhang Bin Xu 《Journal of Environmental Sciences》 2025年第9期762-772,共11页
Regulating the photo-response region of iron metal-organic frameworks(Fe-MOFs)is a viable strategy for enhancing their practical application in the visible-light driven photo-Fenton-like process.This study developed a... Regulating the photo-response region of iron metal-organic frameworks(Fe-MOFs)is a viable strategy for enhancing their practical application in the visible-light driven photo-Fenton-like process.This study developed a novel pyrazine-based Fe-MOFs(MIL-101(Fe)-Pz)by substituting the 1,4-dicarboxybenzene acid ligands in typical MIL-101(Fe)with 2,5-pyrazinedicarboxylic acid(PzDC),in which sodium acetate was used as coordinative modulator to control the crystal size(2–3μm).The incorporation of Fe-pyridine N coordination structures originated from PzDC ligands gave MIL-101(Fe)-Pz narrowed band gap(1.45 eV)than MIL-101(Fe)(2.54 eV)resulting in improved visible-light adsorption capacity(λ>420 nm),and also increased the proportion of Fe(Ⅱ)in the Fe-clusters.Thus MIL-101(Fe)-Pz exhibited a synergistic enhanced photo-Fenton-like catalytic performance under visible-light irradiation.The MIL-101(Fe)-Pz/H_(2)O_(2)/Vis system could degrade 99%of sulfamethoxazolewithin 30min,whichwas 10-fold faster than that of the pristine MIL-101(Fe),it also effectively removed other organic micropollutants with high durability and stability.Mechanistic analysis revealed that the PzDC ligands substitution decreased the band gap of MIL-101(Fe),giving MIL-101(Fe)-Pz appropriate band structure(-0.40∼1.05 V vs.NHE)which can cover several light-driven process for the generation of reactive oxygen species,including Fe(Ⅲ)reduction and H_(2)O_(2) activation for accelerating•OH generation,as well as oxygen reduction reaction for generating H_(2)O_(2),O_(2)^(•−) and ^(1)O_(2).This study highlights the role of pyridine-N containing ligands in regulating the band structure of Fe-MOFs,providing valuable guidance for the design of Fe-MOFs photocatalysts. 展开更多
关键词 Fe-MOFs Pyrazine ligands Photocatalysis Visible light Fenton-like process
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Critical processes controlling the formation of visible gold in the giant Jiaodong gold province:Constraints from microtextural and geochemical analyses by SEM,TOF-SIMS,and LA-(MC)-ICP-MS
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作者 Hong Wang Ting-Guang Lan +6 位作者 Lang-Ye Zhao Hong-Rui Fan Zhan-Ping Li Huan-Long Hu Zi-Qi Xu Hong-Wei Peng Lei Shu 《Acta Geochimica》 2025年第6期1167-1185,共19页
The world-class Jiaodong gold province in the North China Craton hosts over 5000 t of Au resource and is characterized by abundant visible gold mineralization.However,the critical processes controlling the formation o... The world-class Jiaodong gold province in the North China Craton hosts over 5000 t of Au resource and is characterized by abundant visible gold mineralization.However,the critical processes controlling the formation of visible gold in this province remain poorly understood.To solve this problem,integrated microtextural,trace elemental,and sulfur isotopic analyses of pyrite from the high-grade Linglong gold deposit in the Jiaodong gold province were conducted in this study.Two distinct pyrite types were identified within auriferous quartz-sulfide veins:(1)Py1 aggregates in quartz-pyrite veins(hydrothermal stageⅡ),and(2)euhedral to subhedral,coarse-grained Py2 crystals in quartz-polymetallic sulfide veins(hydrothermal stageⅢ).Microtextural and elemental analyses revealed that visible gold predominantly occurs as intergranular particles between primary pyrite crystals within Py1 aggregates.The Py1 exhibits complex microtextures with abundant mineral inclusions of polymetallic sulfides and has low concentrations of Au(median:0.032 ppm)with a narrowδ^(34)S range(4.86‰-6.75‰),indicative of rapid crystallization under unstable,disequilibrium conditions.By contrast,the Py2 is texturally homogeneous and contains higher Au concentrations(median:0.304 ppm)with progressively increasingδ^(34)S values(5.25‰-10.14‰)over time,suggesting slow crystal growth under more stable,near-equilibrium conditions.Based on the microtextural and geochemical information,it is proposed that fluid boiling occurred only during the hydrothermal stage Ⅱ,which resulted in the unstable physicochemical environment and rapid deposition of gold.During the boiling processes,gold colloids likely occurred and promoted the formation of visible gold. 展开更多
关键词 Visible gold deposition PYRITE GEOCHEMISTRY Jiaodong gold province Microtextural analyses
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HaIVFusion: Haze-Free Infrared and Visible Image Fusion
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作者 Xiang Gao Yongbiao Gao +2 位作者 Aimei Dong Jinyong Cheng Guohua Lv 《IEEE/CAA Journal of Automatica Sinica》 2025年第10期2040-2055,共16页
The purpose of infrared and visible image fusion is to create a single image containing the texture details and significant object information of the source images,particularly in challenging environments.However,exis... The purpose of infrared and visible image fusion is to create a single image containing the texture details and significant object information of the source images,particularly in challenging environments.However,existing image fusion algorithms are generally suitable for normal scenes.In the hazy scene,a lot of texture information in the visible image is hidden,the results of existing methods are filled with infrared information,resulting in the lack of texture details and poor visual effect.To address the aforementioned difficulties,we propose a haze-free infrared and visible fusion method,termed HaIVFusion,which can eliminate the influence of haze and obtain richer texture information in the fused image.Specifically,we first design a scene information restoration network(SIRNet)to mine the masked texture information in visible images.Then,a denoising fusion network(DFNet)is designed to integrate the features extracted from infrared and visible images and remove the influence of residual noise as much as possible.In addition,we use color consistency loss to reduce the color distortion resulting from haze.Furthermore,we publish a dataset of hazy scenes for infrared and visible image fusion to promote research in extreme scenes.Extensive experiments show that HaIVFusion produces fused images with increased texture details and higher contrast in hazy scenes,and achieves better quantitative results,when compared to state-ofthe-art image fusion methods,even combined with state-of-the-art dehazing methods. 展开更多
关键词 Deep learning dehazing image fusion infrared image visible image
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Experimental study on egress capacity of key facilities in pressurized oxygen-supplement compartments
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作者 Kai-Qiang Wang Xue-Hua Song +5 位作者 Wei-Jun Liu Kang Wen Zhi-Gang Shi Jun Zhang Bin Yao Wei-Guo Song 《Chinese Physics B》 2025年第1期536-546,共11页
Pressurized buildings have emerged as a novel architectural solution to alleviate altitude illness in high-altitude regions.Unlike conventional buildings,evacuation from this kind of building has to experience a depre... Pressurized buildings have emerged as a novel architectural solution to alleviate altitude illness in high-altitude regions.Unlike conventional buildings,evacuation from this kind of building has to experience a depressurization time,which results in air expansion and heat absorption,creating a dense fog and impairing sight within the buildings.Evacuation experiments were performed in a pressurized oxygen-supplement compartment to investigate the pedestrian motion properties.Based on the questionnaires,participants reported varying degrees of symptoms such as ear blockage,reduced environmental noise,and dizziness,which had a measurable impact on their mobility.We focus on the evacuation parameters through three basic building components:staircases,pressure transition cabins,and escape windows.As the visibility in the compartment decreases from high to low,the movement patterns of pedestrian shift from triangular to single-file with a significant decline in evacuation efficiency.It is found that there is a linear relationship between evacuation time and the number of evacuees through escape windows.The pressure transition cabin is a crucial evacuation route in emergencies,and evacuation time is recommended as the key metric for assessing its effectiveness.These findings offer valuable insights for emergency evacuation strategies in pressurized buildings. 展开更多
关键词 ALTITUDE VISIBILITY ARCHITECTURAL
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