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Multiscale feature learning and attention mechanism for infrared and visible image fusion

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Science China(Technological Sciences) 2024年第2期67卷 408-422页

作者： GAO li luo Delin wang Song School of Aerospace Engineering Xiamen UniversityXiamen 361102China Electric Power Research Institute China Southern Power GridGuangzhou 510063China

Current fusion methods for infrared and visible images tend to extract features at a single scale,which results in insufficient detail and incomplete feature *** address these issues,we propose an infrared and visible image fusion network based on a multiscale feature learning and attention mechanism(MsAFusion).A multiscale dilation convolution framework is employed to capture image features across various scales and broaden the perceptual ***,an attention network is introduced to enhance the focus on salient targets in infrared images and detailed textures in visible *** compensate for information loss during convolution,jump connections are utilized during the image reconstruction *** fusion process utilizes a combined loss function consisting of pixel loss and gradient loss for unsupervised fusion of infrared and visible *** experiments on the dataset of electricity facilities demonstrate that our proposed method outperforms nine state-of-theart methods in terms of visual perception and four objective evaluation metrics.

关键词： infrared and visible images image fusion attention mechanism CNN feature extraction

A double-layer radiative cooling coating that utilizes the refractive index difference between layers to achieve extremely high solar reflectivity

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Science China Technological Sciences 2024年第10期67卷 3182-3189页

作者： wang FuQiang li ChunZhe YANG ZhenNing XIE WeiXin li Xiang XU ZengHui YAN yuying CHENG ZiMing School of Energy Science and Engineering Harbin Institute of Technology School of New Energy Harbin Institute of Technology at Weihai China Construction Eco-Environmental Protection Technology Co. Ltd. Faculty of Engineering University of Nottingham

Passive daytime radiative cooling（PDRC） technology has great potential in reducing cooling energy consumption. In order to further improve the spectral performance of PDRC coatings, current researchers mostly focus on the selection and size design of functional particles, while ignoring the optical properties enhancement effect caused by the interlayer binder. In this study, based on the principle that the refractive index difference between layers enhanced the backscattering performance of the solar spectrum, we proposed and manufactured a double-layer PDRC coating with polyvinylidene difluoride（PVDF） as the filmforming material in the upper layer and polydimethylsiloxane（PDMS） as the film-forming material in the lower layer, both filled with Al2O3and SiO2particles. The double-layer PDRC coating exhibited excellent spectral performance that a high solar reflectivity of 98% and an emissivity of 0.95 at the “atmospheric window” band. In comparison, the solar spectrum reflectivity of the single-layer PDRC coatings based on PVDF and PDMS of the same thickness was 95% and 94.7%, respectively. Outdoor tests showed that the PDRC coating achieved a temperature decrease of up to 7.1℃ under direct sunlight at noon time. In addition, the PDRC coating had excellent weather resistance, water resistance, and other basic properties. This article opens up a new idea and provides methodological guidance for the design of double-layer PDRC coatings.

关键词： double-layer radiative cooling coating spectral modulation interlayer refractive index solar energy radiative transfer

Crack propagation and damage evolution of metallic cylindrical shells under internal explosive loading

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Defence Technology（防务技术） 2024年第9期39卷 133-146页

作者： Yusong luo Weibing li Junbao li Wenbin li Xiaoming wang ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjing210094China

This paper investigates the three-dimensional crack propagation and damage evolution process of metallic column shells under internal explosive *** calibration of four typical failure parameters for 40CrMnSiB steel was conducted through experiments and subsequently applied to *** numerical simulation results employing the four failure criteria were compared with the differences and similarities observed in freeze-recovery tests and ultra-high-speed *** analysis addressed the critical issue of determining failure criteria for the fracture of a metal shell under internal explosive *** upon this foundation,the damage parameter D_(c),linked to the cumulative crack density,was defined based on the evolution characteristics of a substantial number of *** relationship between the damage parameter and crack velocity over time was established,and the influence of the internal central pressure on the damage parameter and crack velocity was *** in the fracture modes were found under different failure criteria,with the principal strain failure criterion proving to be the most effective for simulating 3D crack propagation in a pure shear fracture *** statistical analysis of the shell penetration fracture radius data,it was determined that the fracture radius remained essentially constant during the crack evolution process and could be considered a *** propagation velocity of axial cracks ranged between 5300 m/s and 12600 m/s,surpassing the Rayleigh wave velocity of the shell material and decreasing linearly with *** increase in shell damage exhibited an initial rapid phase,followed by deceleration,demonstrating accelerated damage during the propagation stage of the blast wave and decelerated damage after the arrival of the rarefaction *** study provides an effective approach for investigating crack propagation and damage *** derived crack propagation and damage evolution law s

关键词： Internal explosive loading Failure criterion Crack propagation Damage evolution Freeze-recovery test

Photoinduced generation of alkyl and phthalimide nitrogen radicals from N-hydroxyphthalimide esters for the synthesis of benzophenone-type bioisosteres

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Science China Chemistry 2024年第10期67卷 3389-3396页

作者： Fei li Jianyang Dong Huijuan liao Jiayi Dang Xuechen Zhou yuying wang Chenya wang Qin Jiang Gang li Dong Xue Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education and School of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi’an 710119China

N-Hydroxyphthalimide(NHPI)esters have emerged as powerful sources of alkyl radicals generated by single-electron transfer,but homolysis of NHPI ester to produce an alkyl radical and a phthalimide nitrogen radical is still in its *** this study,we developed a light-induced method for generation of alkyl and phthalimide nitrogen radicals from NHPI esters and subsequent reactions of the radicals with[1.1.1]propellane and aryl aldehydes for rapid generation of bicycle[1.1.1]pentane *** method does not require metals or photosensitizers,features a broad substrate scope(90 examples)and excellent functional group tolerance,and can be used for the functionalization of structurally complex natural products and *** investigations indicate that the reaction involves photoinduced homolytic cleavage of the Cs_(2)CO_(3)-NHPI ester complex to produce alkyl and phthalimide nitrogen radicals and subsequent hydrogen atom transfer between the phthalimide nitrogen radical and the aldehyde to generate an acyl radical.

关键词： phthalimide nitrogen radicals aryl aldehydes hydrogen atom transfer bicycle[1.1.1]pentane ketones bioisosteres

Electrochemical filtration for drinking water purification:A review on membrane materials,mechanisms and roles

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Journal of Environmental Sciences 2024年第7期141卷 102-128页

作者： yuying Qi Donghao li Shixuan Zhang Fengxiang li Tao Hua College of Environmental Science and Engineering Nankai UniversityTianjin 300350China Key Laboratory of Pollution Process and Environmental Criteria Ministry of EducationTianjin 300350China Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation Tianjin 300350China

Electrochemical filtration can not only enrich low concentrations of pollutants but also produce reactive oxygen species to interact with toxic pollutants with the assistance of a power supply,making it an effective strategy for drinking water *** addition,the application of electrochemical filtration facilitates the reduction of pretreatment procedures and the use of chemicals,which has outstanding potential for maximizing process simplicity and reducing operating costs,enabling the production of safe drinking water in smaller *** recent years,the research on electrochemical filtration has gradually increased,but there has been a lack of attention on its application in the removal of low concentrations of pollutants from low conductivity *** this review,membrane substrates and electrocatalysts used to improve the performance of electrochemical membranes are briefly ***,the application prospects of emerging single-atom catalysts in electrochemical filtration are also ***,several electrochemical advanced oxidation processes coupled with membrane filtration are described,and the related working mechanisms and their advantages and shortcomings used in drinking water purification are ***,the roles of electrochemical filtration in drinking water purification are presented,and the main problems and future perspectives of electrochemical filtration in the removal of low concentration pollutants are discussed.

关键词： Electrochemical filtration Drinking water Conductive membrane Low concentration Electrocatalyst

Effect of Al_(2)O_(3)fiber on twin intersections-induced dynamic recrystallization in fine-grained TiAl matrix composite

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Journal of Materials Science & Technology 2024年第5期172卷 1-14页

作者： Yaofeng luo Yan wang li wang Bin liu Yong liu State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Dynamic recrystallization(DRX)is of great significance for the thermomechanical processing and microstructural regulation of TiAl ***,the underlying DRX mechanism remains poorly *** this study,an Avrami kinetics model for DRX was established,which was capable of predicting the DRX fraction *** addition,the effect of Al_(2)O_(3)short fiber on the DRX mechanisms of TiAl matrix composite during the isothermal compression was investigated for the first *** re-sults showed that other than inhibiting DRX by particles in the TiAl matrix composites,the addition of Al_(2)O_(3)short fiber accelerated a novel DRX process,which was induced by twinning and twin intersec-tions(TDRX).Thus,this composite exhibited a higher DRX rate than that of the as-cast TiAl monolithic *** origin of the twin intersection and TDRX for the composite was *** stress concentration near the Al_(2)O_(3)fiber was above the critical shear stress for twinning and thus was favorable for the formation of twinning and twin *** high stored strain energy at the regions of twins and twin intersections provided the driving force for *** accelerated the grain refinement in the TiAl matrix near the Al_(2)O_(3)*** present findings would provide a new perspective on DRX mechanisms,and provide the scientific guidance for optimizing the microstructures of TiAl matrix composites.

关键词： TiAl matrix composite Al_(2)O_(3)fiber Twin intersection Dynamic recrystallization

Direct visualization of laser-driven dynamic fragmentation in tin by in situ x-ray diffraction

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Matter and Radiation at Extremes 2024年第5期9卷 109-114页

作者： Jing Yang Xinxin wang liang Xu Qiannan wang Yi Sun Jiangtao li lin Zhang Yinghua li yuying Yu Pei wang Qiang Wu Jianbo Hu Laboratory for Shock Wave and Detonation Physics Institute of Fluid PhysicsChina Academy of Engineering PhysicsMianyang 621900China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100094China

We present a novel method for investigating laser-driven dynamic fragmentation in tin using in situ X-ray *** experimental results demonstrate the feasibility of the method for simultaneously identifying the phase and temperature of fragments through analysis of the diffraction ***,we observe a deviation from the widely accepted isentropic release assumption,with the temperature of the fragments being found to be more than 100 K higher than expected,owing to the release of plastic work during dynamic *** findings are further verified through extensive large-scale molecular dynamics simulations,in which strain energies are found to be transferred into thermal energies during the nucleation and growth of voids,leading to an increase in *** findings thus provide crucial insights into the impact-driven dynamic fragmentation phenomenon and reveal the significant influence of plastic work on material response during shock release.

关键词： dynamic release diffraction

A Distributed Adaptive Second-Order Latent Factor Analysis Model

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IEEE/CAA Journal of Automatica Sinica 2024年第11期11卷 2343-2345页

作者： Jialiang wang Weiling li Xin luo the School of Computer Science and Technology Dongguan University of Technology the College of Computer and Information Science Southwest University

Dear Editor,This letter presents a distributed adaptive second-order latent factor(DAS) model for addressing the issue of high-dimensional and incomplete data representation. Compared with first-order optimizers, a second-order optimizer has stronger ability in approaching a better solution when dealing with the non-convex optimization problems, thus obtaining better performance in extracting the latent factors(LFs) well representing the known information from high-dimensional and incomplete data.

关键词： Particle swarm optimization (PSO)

lignin‐derived carbon with pyridine N‐B doping and a nanosandwich structure for high and stable lithium storage

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Carbon Energy 2024年第8期6卷 232-247页

作者： Dichao Wu Jiayuan li yuying Zhao Ao wang Gaoyue Zhang Jianchun Jiang Mengmeng Fan Kang Sun Key Lab of Biomass Energy and Material Jiangsu ProvinceNational Engineering Lab for Biomass Chemical UtilizationKey and Open Lab on Forest Chemical EngineeringSFAInstitute of Chemical Industry of Forest ProductsChinese Academy of ForestryNanjingChina Jiangsu Co‐Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjingChina School of Energy and Environment Southeast UniversityNanjingChina Department of Chemistry Tsinghua UniversityBeijingChina Fujian Provincial Key Laboratory of Biomass Low‐Carbon Conversion Academy of Advanced Carbon Conversion TechnologyHuaqiao UniversityXiamenChina Chinese Academy of Sciences Xinjiang lihua Institute of Technology UrumqiChina

Biomass‐derived carbon is a promising electrode material in energy storage ***,how to improve its low capacity and stability,and slow diffusion kinetics during lithium storage remains a *** this research,we propose a“self‐assembly‐template”method to prepare B,N codoped porous carbon(BN‐C)with a nanosandwich structure and abundant pyridinic N‐B *** nanosandwich structure can increase powder density and cycle stability by constructing a stable solid electrolyte interphase film,shortening the li^(+)diffusion pathway,and accommodating volume expansion during repeated charging/*** abundant pyridinic N‐B species can simultaneously promote the adsorption/desorption of li^(+)/PF_(6)^(−)and reduce the diffusion *** BN‐C electrode showed a high lithium‐ion storage capacity of above 1140 mAh g^(−1)at 0.05 A g^(−1)and superior stability(96.5%retained after 2000 cycles).Moreover,owing to the synergistic effect of the nanosandwich structure and pyridinic N‐B species,the assembled symmetrical BN‐C//BN‐C full cell shows a high energy density of 234.7Wh kg^(−1),high power density of 39.38 kW kg−1,and excellent cycling stability,superior to most of the other cells reported in the *** the density functional theory simulation demonstrated,pyridinic N‐B shows enhanced adsorption activity for li^(+)and PF_(6)^(−),which promotes an increase in the capacity of the anode and cathode,***,the relatively lower diffusion barrier of pyridinic N‐B promotes li^(+)migration,resulting in good rate ***,this study provides a new approach for the synergistic modulation of a nanostructure and an active site simultaneously to fabricate the carbon electrode material in energy storage devices.

关键词： high cycling stability high energy density lithium‐ion batteries pyridinic N‐B species sandwich structure carbon nanosheet