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Electric-Field-Driven Generative Nanoimprinting for Tilted Metasurface Nanostructures
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作者 Yu Fan Chunhui Wang +6 位作者 Hongmiao Tian Xiaoming Chen Ben QLi Zhaomin Wang Xiangming Li Xiaoliang Chen Jinyou Shao 《Nano-Micro Letters》 2026年第1期290-305,共16页
Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is p... Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is proposed.The electric field applied between the template and the substrate drives the contact,tilting,filling,and holding processes.By accurately controlling the introduced included angle between the flexible template and the substrate,tilted nanostructures with a controllable angle are imprinted onto the substrate,although they are vertical on the template.By flexibly adjusting the electric field intensity and the included angle,large-area uniform-tilted,gradient-tilted,and high-angle-tilted nanostructures are fabricated.In contrast to traditional replication,the morphology of the nanoimprinting structure is extended to customized control.This work provides a cost-effective,efficient,and versatile technology for the fabrication of various large-area tilted metasurface structures.As an illustration,a tilted nanograting with a high coupling efficiency is fabricated and integrated into augmented reality displays,demonstrating superior imaging quality. 展开更多
关键词 Generative nanoimprinting Electric field assistance Tilted metasurface structures Large-area fabrication
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Fission and Fusion of Localized Coherent Structures for a Higher-Order Broer-Kaup System 被引量:8
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作者 MAZheng-Yi ZHENGChun-Long 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6期993-997,共5页
Starting from a Backlund transformation and taking a special ansatz for the function f, we can obtain a much more generalexpression of solution that includes some variable separated functions for the higher-order Broe... Starting from a Backlund transformation and taking a special ansatz for the function f, we can obtain a much more generalexpression of solution that includes some variable separated functions for the higher-order Broer-Kaup system. From this expression, we investigate the interactions of localized coherent structures such as the multi-solitonic excitations and find the novel phenomenon that their interactions have non-elastic behavior because the fission/fusion may occur after the interaction of each localized coherent structure. 展开更多
关键词 higher-order Broer-Kaup system variable separation approach Backlund transformation soliton fission soliton fusion
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Analysis of ocular structural parameters and higher-order aberrations in Chinese children with myopia 被引量:5
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作者 Xue Li Qi Hu +3 位作者 Qian-Ru Wang Zi-Qing Feng Fan Yang Chun-Yu Du 《World Journal of Clinical Cases》 SCIE 2021年第27期8035-8043,共9页
BACKGROUND Myopia and high myopia are global public health concerns.Patients with high myopia account for 0.5%-5.0%of the global population.AIM To examine diopters,axial length(AL),higher-order aberrations,and other o... BACKGROUND Myopia and high myopia are global public health concerns.Patients with high myopia account for 0.5%-5.0%of the global population.AIM To examine diopters,axial length(AL),higher-order aberrations,and other ocular parameters in Chinese children with myopia,to analyze the influence of structural parameters associated with myopia on visual quality,and to provide a theoretical basis for the prevention and treatment of childhood myopia and high myopia.METHODS This study included 195 children aged 6–17 years with myopia.The AL was measured with an ultrasonic ophthalmic diagnostic instrument,and the aberrations,corneal curvature(minimum K1,maximum K2,and average Km),central corneal thickness,anterior chamber depth,and anterior chamber angle were measured using a Sirius three-dimensional anterior segment analyzer.Using a standard formula,the corneal radius of curvature R(337.3/Km)and AL/R values were obtained.RESULTS The diopter of high myopia compared with low-middle myopia was correlated with age and AL(r=-0.336,-0.405,P<0.001),and AL of high myopia was negatively correlated with K1,K2,and Km(r=-0.673,-0.661,and-0.680,respectively;P<0.001),and positively correlated with age and the anterior chamber depth(r=0.214 and 0.275,respectively;P<0.05).AL/R was more closely related to diopter than AL in children with myopia,and 94.4%of children with myopia had an AL/R of>3.00.CONCLUSION The ocular structural parameters of children change because of different diopters.AL/R is more specific and sensitive than AL in evaluating the refractive status of myopia in children.An AL/R of>3.00 may be used as a specific index of myopia in children.There are differences in AL/R between high myopia and low-middle myopia,which can be used for the classification of ametropia.The degree of myopia has a certain influence on higher-order aberrations. 展开更多
关键词 MYOPIA higher-order aberrations DIOPTER Axial length Cornea radius of curvature
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Design Guidelines for Composition of Brazing Filler Metals and Evolution Mechanisms of Typical Microstructures 被引量:5
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作者 Long Weimin 《稀有金属材料与工程》 北大核心 2025年第4期837-853,共17页
Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler ... Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler metals is ever-increasing.It is of great significance to investigate the optimized composition design methods and to establish systematic design guidelines for brazing filler metals.This study elucidated the fundamental rules for the composition design of brazing filler metals from a three-dimensional perspective encompassing the basic properties of applied brazing filler metals,formability and processability,and overall cost.The basic properties of brazing filler metals refer to their mechanical properties,physicochemical properties,electromagnetic properties,corrosion resistance,and the wettability and fluidity during brazing.The formability and processability of brazing filler metals include the processes of smelting and casting,extrusion,rolling,drawing and ring-making,as well as the processes of granulation,powder production,and the molding of amorphous and microcrystalline structures.The cost of brazing filler metals corresponds to the sum of materials value and manufacturing cost.Improving the comprehensive properties of brazing filler metals requires a comprehensive and systematic consideration of design indicators.Highlighting the unique characteristics of brazing filler metals should focus on relevant technical indicators.Binary or ternary eutectic structures can effectively enhance the flow spreading ability of brazing filler metals,and solid solution structures contribute to the formability.By employing the proposed design guidelines,typical Ag based,Cu based,Zn based brazing filler metals,and Sn based solders were designed and successfully applied in major scientific and engineering projects. 展开更多
关键词 design of brazing filler metals design guidelines for composition Ag based brazing filler metals eutectic structures evolution
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Characterization and Analysis of Abnormal Grain Structures in WSTi6421 Titanium Alloy AfterβAnnealing Treatment 被引量:1
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作者 Wang Wensheng Liu Xianghong +5 位作者 Wang Haipeng Wang Kaixuan Tian Yanwen Yan Jianchuan Li Yulu Chen Haisheng 《稀有金属材料与工程》 北大核心 2025年第2期354-362,共9页
As-forged WSTi6421 titanium alloy billet afterβannealing was investigated.Abnormally coarse grains larger than adjacent grains could be observed in the microstructures,forming abnormal grain structures with uneven si... As-forged WSTi6421 titanium alloy billet afterβannealing was investigated.Abnormally coarse grains larger than adjacent grains could be observed in the microstructures,forming abnormal grain structures with uneven size distribution.Through electron backscattered diffraction(EBSD),the forged microstructure at various locations of as-forged WSTi6421 titanium alloy billet was analyzed,revealing that the strength of theβphase cubic texture generated by forging significantly influences the grain size afterβannealing.Heat treatment experiments were conducted within the temperature range from T_(β)−50°C to T_(β)+10°C to observe the macro-and micro-morphologies.Results show that the cubic texture ofβphase caused by forging impacts the texture of the secondaryαphase,which subsequently influences theβphase formed during the post-βannealing process.Moreover,the pinning effect of the residual primaryαphase plays a crucial role in the growth ofβgrains during theβannealing process.EBSD analysis results suggest that the strength ofβphase with cubic texture formed during forging process impacts the orientation distribution differences ofβgrains afterβannealing.Additionally,the development of grains with large orientations within the cubic texture shows a certain degree of selectivity duringβannealing,which is affected by various factors,including the pinning effect of the primaryαphase,the strength of the matrix cubic texture,and the orientation relationship betweenβgrain and matrix.Comprehensively,the stronger the texture in a certain region,the less likely the large misoriented grains suffering secondary growth,thereby aggregating the difference in microstructure and grain orientation distribution across different regions afterβannealing. 展开更多
关键词 WSTi6421 titanium alloy βannealing abnormal grain structure
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SCS-Net:A DNN-based electromagnetic shielding effectiveness analysis method for slotted composite structures 被引量:1
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作者 Wanli DU Guangzhi CHEN +4 位作者 Ziang ZHANG Xinsong WANG Shunchuan YANG Xingye CHEN Donglin SU 《Chinese Journal of Aeronautics》 2025年第3期505-520,共16页
As the proportion of composite materials used in aircraft continues to increase, the electromagnetic Shielding Effectiveness (SE) of these materials becomes a critical factor in the electromagnetic safety design of ai... As the proportion of composite materials used in aircraft continues to increase, the electromagnetic Shielding Effectiveness (SE) of these materials becomes a critical factor in the electromagnetic safety design of aircraft structures. The assessment of electromagnetic SE for Slotted Composite Structures(SCSs) is particularly challenging due to their complex geometries and there remains a lack of suitable models for accurately predicting the SE performance of these intricate configurations. To address this issue, this paper introduces SCS-Net, a Deep Neural Network (DNN) method designed to accurately predict the SE of SCS. This method considers the impacts of various structural parameters, material properties and incident wave parameters on the SE of SCSs. In order to better model the SCS, an improved Nicolson-Ross-Weir (NRW) method is introduced in this paper to provide an equivalent flat structure for the SCS and to calculate the electromagnetic parameters of the equivalent structure. Additionally, the prediction of SE via DNNs is limited by insufficient test data, which hinders support for large-sample training. To address the issue of limited measured data, this paper develops a Measurement-Computation Fusion (MCF) dataset construction method. The predictions based on the simulation results show that the proposed method maintains an error of less than 0.07 dB within the 8–10 GHz frequency range. Furthermore, a new loss function based on the weighted L1-norm is established to improve the prediction accuracy for these parameters. Compared with traditional loss functions, the new loss function reduces the maximum prediction error for equivalent electromagnetic parameters by 47%. This method significantly improves the prediction accuracy of SCS-Net for measured data, with a maximum improvement of 23.88%. These findings demonstrate that the proposed method enables precise SE prediction and design for composite structures while reducing the number of test samples needed. 展开更多
关键词 Deep neural networkcs Measurement-computation fusion Electromagnetic shielding effectiveness Slotted composite structures structural paranmeters
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Higher-order effects on self-similar parabolic pulse in the microstructured fibre amplifier 被引量:1
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作者 刘伟慈 徐文成 +3 位作者 冯杰 陈伟成 李书贤 刘颂豪 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期1025-1028,共4页
By considering higher-order effects, the properties of self-similar parabolic pulses propagating in the microstructured fibre amplifier with a normal group-velocity dispersion have been investigated. The numerical res... By considering higher-order effects, the properties of self-similar parabolic pulses propagating in the microstructured fibre amplifier with a normal group-velocity dispersion have been investigated. The numerical results indicate that the higher-order effects can badly distort self-similar parabolic pulse shape and optical spectrum, and at the same time the peak shift and oscillation appear, while the pulse still reveals highly linear chirp but grows into asymmetry. The influence of different higher-order effects on self-similar parabolic pulse propagation has been analysed. It shows that the self-steepening plays a more important role. We can manipulate the geometrical parameters of the microstructured fibre amplifier to gain a suitable dispersion and nonlinearity coefficient which will keep high-quality self-similar parabolic pulse propagation. These results are significant for the further study of self-similar parabolic pulse propagation. 展开更多
关键词 self-similar parabolic pulse microstructured fibre amplifier higher-order dispersion nonlinear effect
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A New Technique for Constructing Higher-order Iterative Methods to Solve Nonlinear Systems
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作者 XIAO Xiaoyong 《应用数学》 北大核心 2025年第3期762-774,共13页
In this paper,a new technique is introduced to construct higher-order iterative methods for solving nonlinear systems.The order of convergence of some iterative methods can be improved by three at the cost of introduc... In this paper,a new technique is introduced to construct higher-order iterative methods for solving nonlinear systems.The order of convergence of some iterative methods can be improved by three at the cost of introducing only one additional evaluation of the function in each step.Furthermore,some new efficient methods with a higher-order of convergence are obtained by using only a single matrix inversion in each iteration.Analyses of convergence properties and computational efficiency of these new methods are made and testified by several numerical problems.By comparison,the new schemes are more efficient than the corresponding existing ones,particularly for large problem sizes. 展开更多
关键词 Systems of nonlinear equation Order of convergence higher-order method Extended Newton iteration Computational efficiency
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Dynamic Structural Colors in Helical Superstructures:from Supramolecules to Polymers 被引量:1
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作者 Bo Ji Lang Qin Yan-Lei Yu 《Chinese Journal of Polymer Science》 2025年第3期406-428,共23页
Cholesteric liquid crystals(CLCs)exhibit unique helical superstructures that selectively reflect circularly polarized light,enabling them to dynamically respond to environmental changes with tunable structural colors.... Cholesteric liquid crystals(CLCs)exhibit unique helical superstructures that selectively reflect circularly polarized light,enabling them to dynamically respond to environmental changes with tunable structural colors.This dynamic color-changing capability is crucial for applications that require adaptable optical properties,positioning CLCs as key materials in advanced photonic technologies.This review focuses on the mechanisms of dynamic color tuning in CLCs across various forms,including small molecules,cholesteric liquid crystal elastomers(CLCEs),and cholesteric liquid crystal networks(CLCNs),and emphasizes the distinct responsive coloration each structure provides.Key developments in photochromic mechanisms based on azobenzene,dithienylethene,and molecular motor switches,are discussed for their roles in enhancing the stability and tuning range of CLCs.We examine the color-changing behaviors of CLCEs under mechanical stimuli and CLCNs under swelling,highlighting the advantages of each form.Following this,applications of dynamic color-tuning CLCs in information encryption,adaptive camouflage,and smart sensing technologies are explored.The review concludes with an outlook on current challenges and future directions in CLC research,particularly in biomimetic systems and dynamic photonic devices,aiming to broaden their functional applications and impact. 展开更多
关键词 structural colors Cholesteric liquid crystals Elastomers Polymer network
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Development of mechanical equivalent porous structures for 3Dprinted artificial femoral heads 被引量:1
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作者 Moyu Liu Jun Wang +3 位作者 Yu Li Kaiyuan Cheng Yong Huan Ning Li 《Acta Mechanica Sinica》 2025年第4期176-187,共12页
The current artificial bone is unable to accurately replicate the inhomogeneity and anisotropy of human cancellous bone.To address this issue,we proposed a personalized approach based on clinical CT images to design m... The current artificial bone is unable to accurately replicate the inhomogeneity and anisotropy of human cancellous bone.To address this issue,we proposed a personalized approach based on clinical CT images to design mechanical equivalent porous structures for artificial femoral heads.Firstly,supported by Micro and clinical CT scans of 21 bone specimens,the anisotropic mechanical parameters of human cancellous bone in the femoral head were characterized using clinical CT values(Hounsfield unit).After that,the equivalent porous structure of cancellous bone was designed based on the gyroid surface,the influence of its degree of anisotropy and volume fraction on the macroscopic mechanical parameters was investigated by finite element analysis.Furthermore,a mapping relationship between CT values and the porous structure was established by jointly solving the mechanical parameters of the porous structure and human cancellous bone,allowing the design of personalized gradient porous structures based on clinical CT images.Finally,to verify the mechanical equivalence,implant press-in tests were conducted on 3D-printed artificial femoral heads and human femoral heads,the influence of the porous structure’s cell size in bone-implant interaction problems was also explored.Results showed that the minimum deviations of press-in stiffness(<15%)and peak load(<5%)both occurred when the cell size was 20%to 30%of the implant diameter.In conclusion,the designed porous structure can replicate the human cancellous bone-implant interaction at a high level,indicating its effectiveness in optimizing the mechanical performance of 3D-printed artificial femoral head. 展开更多
关键词 Mechanical equivalence Porous structure ANISOTROPY Femoral head Artificial bone
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Magneto-Electro-Elastic Analysis of Doubly-Curved Shells: Higher-Order Equivalent Layer-Wise Formulation
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作者 Francesco Tornabene Matteo Viscoti Rossana Dimitri 《Computer Modeling in Engineering & Sciences》 2025年第2期1767-1838,共72页
Recent engineering applications increasingly adopt smart materials,whose mechanical responses are sensitive to magnetic and electric fields.In this context,new and computationally efficient modeling strategies are ess... Recent engineering applications increasingly adopt smart materials,whose mechanical responses are sensitive to magnetic and electric fields.In this context,new and computationally efficient modeling strategies are essential to predict the multiphysic behavior of advanced structures accurately.Therefore,the manuscript presents a higher-order formulation for the static analysis of laminated anisotropic magneto-electro-elastic doubly-curved shell structures.The fundamental relations account for the full coupling between the electric field,magnetic field,and mechanical elasticity.The configuration variables are expanded along the thickness direction using a generalized formulation based on the Equivalent Layer-Wise approach.Higher-order polynomials are selected,allowing for the assessment of prescribed values of the configuration variables at the top and bottom sides of solids.In addition,an effective strategy is provided for modeling general surface distributions of mechanical pressures and electromagnetic external fluxes.The model is based on a continuum-based formulation which employs an analytical homogenization of the multifield material properties,based on Mori&Tanaka approach,of a magneto-electro-elastic composite material obtained from a piezoelectric and a piezomagnetic phase,with coupled magneto-electro-elastic effects.A semi-analytical Navier solution is applied to the fundamental equations,and an efficient post-processing equilibrium-based procedure is here used,based on the numerical assessment with the Generalized Differential Quadrature(GDQ)method,to recover the response of three-dimensional shells.The formulation is validated through various examples,investigating the multifield response of panels of different curvatures and lamination schemes.An efficient homogenization procedure,based on the Mori&Tanaka approach,is employed to obtain the three-dimensional constitutive relation of magneto-electro-elastic materials.Each model is validated against three-dimensional finite-element simulations,as developed in commercial codes.Furthermore,the full coupling effect between the electric and magnetic response is evaluated via a parametric investigation,with useful insights for design purposes of many engineering applications.The paper,thus,provides a formulation for the magneto-electro-elastic analysis of laminated structures,with a high computational efficiency,since it provides results with three-dimensional capabilities with a two-dimensional formulation.The adoption of higher-order theories,indeed,allows us to efficiently predict not only the mechanical response of the structure as happens in existing literature,but also the through-the-thickness distribution of electric and magnetic variables.A novel higher-order theory has been proposed in this work for the magneto-electro-elastic analysis of laminated shell structures with varying curvatures.This theory employs a generalized method to model the distribution of the displacement field components,electrostatic,and magneto-static potential,accounting for higher-order polynomials.The thickness functions have been defined to prescribe the arbitrary values of configuration variables at the top and bottom surfaces,even though the model is ESL-based.The fundamental governing equations have been derived in curvilinear principal coordinates,considering all coupling effects among different physical phenomena,including piezoelectric,piezomagnetic,and magneto-electric effects.A homogenization algorithm based on a Mori&Tanaka approach has been adopted to obtain the equivalent magneto-electro-mechanical properties of a two-phase transversely isotropic composite.In addition,an effective method has been adopted involving the external loads in terms of surface tractions,as well as the electric and magnetic fluxes.In the post-processing stage,a GDQ-based procedure provides the actual 3D response of a doubly-curved solid.The model has been validated through significant numerical examples,showing that the results of this semi-analytical theory align well with those obtained from 3D numerical models from commercial codes.In particular,the accuracy of the model has been verified for lamination schemes with soft layers and various curvatures under different loading conditions.Moreover,this formulation has been used to predict the effect of combined electric and magnetic loads on the mechanical response of panels with different curvatures and lamination schemes.As a consequence,this theory can be applied in engineering applications where the combined effect of electric and magnetic loads is crucial,thus facilitating their study and design.An existing limitation of this study is that the solution is that it is derived only for structures with uniform curvature,cross-ply lamination scheme,and simply supported boundary conditions.Furthermore,it requires that each lamina within the stacking sequence exhibits magneto-electro-elastic behavior.Therefore,at the present stage,it cannot be used for multifield analysis of classical composite structures with magneto-electric patches.A further enhancement of the research work could be the derivation of a solution employing a numerical technique,to overcome the limitations of the Navier method.In this way,the same theory may be adopted to predict the multifield response of structures with variable curvatures and thickness,as well as anisotropic materials and more complicated boundary conditions.Acknowledgement:The authors are grateful to the Department of Innovation Engineering of Univer-sity of Salento for the support. 展开更多
关键词 Magneto-electro-elastic materials equivalent layer-wise generalized differential quadrature higher-order theories navier solution recovery procedure smart structures
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Theoretical Insights into the Atomic and Electronic Structures of Polyperyleneimide:On the Origin of Photocatalytic Oxygen Evolution Activity
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作者 Yi-Qing Wang Zhi Lin +1 位作者 Ming-Tao Li Shao-Hua Shen 《电化学(中英文)》 北大核心 2025年第5期28-36,共9页
Polymeric perylene diimide(PDI)has been evidenced as a good candidate for photocatalytic water oxidation,yet the origin of the photocatalytic oxygen evolution activity remains unclear and needs further exploration.Her... Polymeric perylene diimide(PDI)has been evidenced as a good candidate for photocatalytic water oxidation,yet the origin of the photocatalytic oxygen evolution activity remains unclear and needs further exploration.Herein,with crystal and atomic structures of the self-assembled PDI revealed from the X-ray diffraction pattern,the electronic structure is theoretically illustrated by the first-principles density functional theory calculations,suggesting the suitable band structure and the direct electronic transition for efficient photocatalytic oxygen evolution over PDI.It is confirmed that the carbonyl O atoms on the conjugation structure serve as the active sites for oxygen evolution reaction by the crystal orbital Hamiltonian group analysis.The calculations of reaction free energy changes indicate that the oxygen evolution reaction should follow the reaction pathway of H_(2)O→^(*)OH→^(*)O→^(*)OOH→^(*)O_(2)with an overpotential of 0.81 V.Through an in-depth theoretical computational analysis in the atomic and electronic structures,the origin of photocatalytic oxygen evolution activity for PDI is well illustrated,which would help the rational design and modification of polymeric photocatalysts for efficient oxygen evolution. 展开更多
关键词 Photocatalytic oxygen evolution Polymeric perylene diimide Atomic structure Electronic structure Reaction pathway
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Highly Thermally Conductiveand Flame-Retardant Waterborne Polyurethane Composites with 3D BNNS Bridging Structures via MagneticField Assistance 被引量:1
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作者 Hao Jiang Yuhui Xie +7 位作者 Mukun He Jindao Li Feng Wu Hua Guo Yongqiang Guo Delong Xie Yi Mei Junwei Gu 《Nano-Micro Letters》 2025年第6期279-296,共18页
The microstructure design for thermal conduction pathways in polymeric electrical encapsulation materials is essential to meet the stringent requirements for efficient thermal management and thermal runaway safety in ... The microstructure design for thermal conduction pathways in polymeric electrical encapsulation materials is essential to meet the stringent requirements for efficient thermal management and thermal runaway safety in modern electronic devices.Hence,a composite with three-dimensional network(Ho/U-BNNS/WPU)is developed by simultaneously incorporating magnetically modified boron nitride nanosheets(M@BNNS)and non-magnetic organo-grafted BNNS(U-BNNS)into waterborne polyurethane(WPU)to synchronous molding under a horizontal magnetic field.The results indicate that the continuous in-plane pathways formed by M@BNNS aligned along the magnetic field direction,combined with the bridging structure established by U-BNNS,enable Ho/U-BNNS/WPU to exhibit exceptional in-plane(λ//)and through-plane thermal conductivities(λ_(⊥)).In particular,with the addition of 30 wt%M@BNNS and 5 wt%U-BNNS,theλ//andλ_(⊥)of composites reach 11.47 and 2.88 W m^(-1) K^(-1),respectively,which representing a 194.2%improvement inλ_(⊥)compared to the composites with a single orientation of M@BNNS.Meanwhile,Ho/U-BNNS/WPU exhibits distinguished thermal management capabilities as thermal interface materials for LED and chips.The composites also demonstrate excellent flame retardancy,with a peak heat release and total heat release reduced by 58.9%and 36.9%,respectively,compared to WPU.Thus,this work offers new insights into the thermally conductive structural design and efficient flame-retardant systems of polymer composites,presenting broad application potential in electronic packaging fields. 展开更多
关键词 Boron nitride nanosheets Magnetic response structural design Thermal conductivity Flame retardancy
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Effects of bamboo invasion on forest structures and diameter–height allometries 被引量:1
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作者 Ming Ouyang Anwar Eziz +8 位作者 Shuli Xiao Wenjing Fang Qiong Cai Suhui Ma Jiangling Zhu Qingpei Yang Jinming Hu Zhiyao Tang Jingyun Fang 《Forest Ecosystems》 2025年第1期38-45,共8页
Forest structure is fundamental in determining ecosystem function,yet the impact of bamboo invasion on these structural characteristics remains unclear.We investigated 219 invasion transects at 41 sites across the dis... Forest structure is fundamental in determining ecosystem function,yet the impact of bamboo invasion on these structural characteristics remains unclear.We investigated 219 invasion transects at 41 sites across the distribution areas of Moso bamboo(Phyllostachys edulis)in China to explore the effects of bamboo invasion on forest structural attributes and diameter–height allometries by comparing paired plots of bamboo,mixed bamboo-tree,and non-bamboo forests along the transects.We found that bamboo invasion decreased the mean and maximum diameter at breast height,maximum height,and total basal area,but increased the mean height,stem density,and scaling exponent for stands.Bamboo also had a higher scaling exponent than tree,particularly in mixed forests,suggesting a greater allocation of biomass to height growth.As invasion intensity increased,bamboo allometry became more plastic and decreased significantly,whereas tree allometry was indirectly promoted by increasing stem density.Additionally,a humid climate may favour the scaling exponents for both bamboo and tree,with only minor contributions from topsoil moisture and nitrogen content.The inherent superiority of diameter–height allometry allows bamboo to outcompete tree and contributes to its invasive success.Our findings provide a theoretical basis for understanding the causes and consequences of bamboo invasion. 展开更多
关键词 Moso bamboo Forest structure Stand density DBHHeight allometry Scaling exponent Wetness index
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Regulation of crystal and microstructures of RETaO_(4)(RE=Nd,Sm,Gd.Ho,Er)powders synthesized via co-precipitation 被引量:1
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作者 Jiang Tian Lin Chen +10 位作者 Xunlei Chen Keren Luo Baihui Li Di Zhang Meng Wang Bing Xu Zhiyi Ren Shixiao Yan Xiaoliang Sun Chi Liu Jing Feng 《Journal of Rare Earths》 2025年第6期1246-1255,I0006,共11页
Ferroelastic rare earth tantalates(RETaO_(4))are widely researched as the next-generation thermal barrier coatings(TBCs),and RETaO_(4)powders are hugely significant for synthesizing their coatings.The current research... Ferroelastic rare earth tantalates(RETaO_(4))are widely researched as the next-generation thermal barrier coatings(TBCs),and RETaO_(4)powders are hugely significant for synthesizing their coatings.The current research used chemical co-precipitation within an automated experimental device to synthesize RETaO_(4)(RE=Nd,Sm,Gd,Ho,Er)powders.The device automatically monitored and controlled the solutions'pH,improving the chemical co-precipitation efficiency.The crystal structure and microstructure of the RETaO_(4)powders can be controlled by changing the annealing temperature,and the materials undergo an m'-m phase transition.The m'-RETaO_(4)powders exhibit nano-size grains,while m-RETaO_(4)powders evince micron-size grains,altered by the annealing temperatures.A simultaneous thermal analysis es-timates the reversive ferroelastic tetragonal-monoclinic phase transition temperatures.Overall,this research focuses on the synthesis,crystal structures,microstructures,and phase transition of the fabricated RETaO_(4)powders. 展开更多
关键词 Rare earth tantalates Chemical co-precipitation method Rare earths Crystal structures MICROstructures Annealingtemperatures
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Higher-order optimality conditions for multiobjective optimization through a new type of directional derivatives
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作者 HUANG Zheng-gang 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第3期543-557,共15页
This paper deals with extensions of higher-order optimality conditions for scalar optimization to multiobjective optimization.A type of directional derivatives for a multiobjective function is proposed,and with this n... This paper deals with extensions of higher-order optimality conditions for scalar optimization to multiobjective optimization.A type of directional derivatives for a multiobjective function is proposed,and with this notion characterizations of strict local minima of order k for a multiobjective optimization problem with a nonempty set constraint are established,generalizing the corresponding scalar case obtained by Studniarski[3].Also necessary not sufficient and sufficient not necessary optimality conditions for this minima are derived based on our directional derivatives,which are generalizations of some existing scalar results and equivalent to some existing multiobjective ones.Many examples are given to illustrate them there. 展开更多
关键词 strict local minima of order k multiobjective optimization higher-order optimality conditions higher-order directional derivatives
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3D Printing of Tough Hydrogel Scaffolds with Functional Surface Structures for Tissue Regeneration
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作者 Ke Yao Gaoying Hong +11 位作者 Ximin Yuan Weicheng Kong Pengcheng Xia Yuanrong Li Yuewei Chen Nian Liu Jing He Jue Shi Zihe Hu Yanyan Zhou Zhijian Xie Yong He 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期18-45,共28页
Hydrogel scaffolds have numerous potential applications in the tissue engineering field.However,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and hi... Hydrogel scaffolds have numerous potential applications in the tissue engineering field.However,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical properties.Inspired by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this gap.First,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent biocompatibility.Furthermore,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell growth.Interestingly,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT strategies.Animal experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries. 展开更多
关键词 3D printing Tough hydrogel scaffold Functional surface structure Tissue regeneration BIOMATERIALS
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Mixture of Bacillus Amyloliquefaciens and Bacillus Pumilus Modulates Community Structures of Rice Rhizosphere Soil to Suppress Rice Seedling Blight 被引量:1
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作者 JIANG Nan QIU Jiehua +7 位作者 TIAN Dagang SHI Huanbin LIU Zhiquan WEN Hui XIE Shuwei CHEN Huizhe WU Meng KOU Yanjun 《Rice science》 2025年第1期118-130,I0067-I0070,共17页
Rice seedling blight,caused by various fungi,including Fusarium oxysporum,poses a severe threat to rice production.As awareness grows regarding the environmental and safety hazards associated with the application of f... Rice seedling blight,caused by various fungi,including Fusarium oxysporum,poses a severe threat to rice production.As awareness grows regarding the environmental and safety hazards associated with the application of fungicides for managing rice seedling blight,there has been a shift in focus towards biological control agents.In this study,we isolated biocontrol bacteria from paddy fields that significantly inhibited the growth of F.oxysporum in vitro and identified the strains as Bacillus amyloliquefaciens T40 and Bacillus pumilus T208.Additionally,our findings indicated that the combined application of these Bacillus strains in soil was more effective in reducing the incidence of rice seedling blight than their individual use.Analysis of 16S and internal transcribed spacer rRNA gene sequencing data revealed that the mixture of the T40 and T208 strains exhibited the lowest average clustering coefficients,which were negatively correlated with the biomass of F.oxysporum-inoculated rice seedlings.Furthermore,this mixture led to higher stochastic assembly(average|βNTI|<2)and reduced selection pressures on rice rhizosphere bacteria compared with individual strain applications.The mixture of the T40 and T208 strains also significantly increased the expression of defense-related genes.In conclusion,the mixture of the T40 and T208 strains effectively modulates microbial community structures,enhances microbial network stability,and boosts the resistance against rice seedling blight.Our study supports the development and utilization of biological resources for crop protection. 展开更多
关键词 application strategy disease control disease resistance microbial community structure microbial community assembly process Oryza sativa
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应用Tekla Structures软件完成裂解炉钢结构详细设计图纸
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作者 刘义朋 《石油化工设计》 2025年第3期27-30,I0002,共5页
以裂解炉辐射段钢结构设计为例,介绍如何应用Tekla Structures软件完成裂解炉详细设计图纸。设计过程中实现了将完善的三维模型和二维图纸链接,并将三维模型迅速高效的转化为二维图纸的目标。简化了传统二维出图模式,辅助完成裂解炉钢... 以裂解炉辐射段钢结构设计为例,介绍如何应用Tekla Structures软件完成裂解炉详细设计图纸。设计过程中实现了将完善的三维模型和二维图纸链接,并将三维模型迅速高效的转化为二维图纸的目标。简化了传统二维出图模式,辅助完成裂解炉钢结构在裂解炉制造厂预制和项目现场顺利安装。 展开更多
关键词 裂解炉 Tekla structures 钢结构 详图设计
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Optimal Synchronization of Higher-Order Dynamical Networks
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作者 Guanrong CHEN 《Artificial Intelligence Science and Engineering》 2025年第1期31-36,共6页
This article briefly reviews the topic of complex network synchronization,with its graph-theoretic criterion,showing that the homogeneous and symmetrical network structures are essential for optimal synchronization.Fu... This article briefly reviews the topic of complex network synchronization,with its graph-theoretic criterion,showing that the homogeneous and symmetrical network structures are essential for optimal synchronization.Furthermore,it briefly reviews the notion of higher-order network topologies and shows their promising potential in application to evaluating the optimality of network synchronizability. 展开更多
关键词 complex network SYNCHRONIZATION optimal synchronizability SIMPLEX higher-order topology
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