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Vertical propagation behavior of hydraulic fracture guided by radial borehole:Insight for horizontal well stimulation in multilayered reservoirs
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作者 Tengda Long Gensheng Li +10 位作者 Xiaoguang Wu Zhongwei Huang Zixiao Xie Rui Yang Xianzhi Song Shouceng Tian Haizhu Wang Naikun Hu Xiaohua Wang Xiangyang Wang Xiaoxuan Li 《International Journal of Mining Science and Technology》 2026年第2期229-249,共21页
The strong vertical discontinuities pose a fundamental challenge to optimizing stimulated reservoir volume(SRV)in multilayered reservoirs.This research proposes a radial borehole-assisted horizontal well fracturing te... The strong vertical discontinuities pose a fundamental challenge to optimizing stimulated reservoir volume(SRV)in multilayered reservoirs.This research proposes a radial borehole-assisted horizontal well fracturing technology,which is expected to achieve effective vertical stimulation and commingled production across multiple pay zones.Under different geological and engineering conditions,the vertical propagation behavior of hydraulic fractures guided by radial boreholes can be determined by adjusting the interlayered lithologies and radial borehole configurations in experimental samples.Experimental results reveal four fracture network patterns:passivated,cross-layer,skip-layer,and hybrid fractures in the radial borehole fracturing.The radial boreholes perform better fracture guiding performances in the high-brittleness interlayers,which form cross-layer and hybrid fracture networks to improve the growth height.Hydraulic fractures tend to propagate from high-strength to low-strength layers under radial borehole guidance.When radial boreholes interconnect multiple lithology layers,hydraulic fractures initiate preferentially in lower-strength zones rather than remaining confined to borehole root ends.Increased radial borehole length and diameter facilitate fracture skip-layer initiation and cross-layer propagation,while multiple borehole branches enhance fracture penetration across high-strength interlayers.Radial boreholes with inclination angles below 30°enhance fracture height by generating cross-layer and hybrid fracture networks.Furthermore,an inter-borehole phase angle of less than 180°facilitates single-wing fracture cross-layer propagation.Fracture height is primarily governed by radial borehole length,followed by quantity,inclination angle,and diameter.Based on the geometric similarity criteria,the recommended parameters for radial borehole-assisted fracturing in a 5 1/2-inch horizontal well include a length>15 m,an inclination angle<30°,and a diameter>52 mm to ensure effective stimulation across three or more pay zones.Finally,the field-scale numerical model was developed to simulate the optimized radial borehole fracturing and demonstrate the technical superiority.These findings are expected to provide an in-depth understanding of the effective stimulation in multilayered reservoirs. 展开更多
关键词 multilayered reservoirs Radial borehole fracturing Interlayered lithologies Radial borehole configurations Field-scale numerical model
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Intralayer structure reconstruction of general weighted output-coupling multilayer complex networks
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作者 Xinwei Wang Yayong Wu +1 位作者 Ying Zheng Guo-Ping Jiang 《Chinese Physics B》 2026年第2期287-299,共13页
Multilayer complex dynamical networks,characterized by the intricate topological connections and diverse hierarchical structures,present significant challenges in determining complete structural configurations due to ... Multilayer complex dynamical networks,characterized by the intricate topological connections and diverse hierarchical structures,present significant challenges in determining complete structural configurations due to the unique functional attributes and interaction patterns inherent to different layers.This paper addresses the critical question of whether structural information from a known layer can be used to reconstruct the unknown intralayer structure of a target layer within general weighted output-coupling multilayer networks.Building upon the generalized synchronization principle,we propose an innovative reconstruction method that incorporates two essential components in the design of structure observers,the cross-layer coupling modulator and the structural divergence term.A key advantage of the proposed reconstruction method lies in its flexibility to freely designate both the unknown target layer and the known reference layer from the general weighted output-coupling multilayer network.The reduced dependency on full-state observability enables more deployment in engineering applications with partial measurements.Numerical simulations are conducted to validate the effectiveness of the proposed structure reconstruction method. 展开更多
关键词 multilayer network structure reconstruction cross-layer coupling modulator output coupling
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Influence of Process Parameters on Forming Quality of Single-Channel Multilayer by Joule Heat Fuse Additive Manufacturing
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作者 Li Suli Fan Longfei +3 位作者 Chen Jichao Gao Zhuang Xiong Jie Yang Laixia 《稀有金属材料与工程》 北大核心 2025年第5期1165-1176,共12页
To overcome the shortage of complex equipment,large volume,and high energy consumption in space capsule manufacturing,a novel sliding pressure Joule heat fuse additive manufacturing technique with reduced volume and l... To overcome the shortage of complex equipment,large volume,and high energy consumption in space capsule manufacturing,a novel sliding pressure Joule heat fuse additive manufacturing technique with reduced volume and low energy consumption was proposed.But the unreasonable process parameters may lead to the inferior consistency of the forming quality of single-channel multilayer in Joule heat additive manufacturing process,and it is difficult to reach the condition for forming thinwalled parts.Orthogonal experiments were designed to fabricate single-channel multilayer samples with varying numbers of layers,and their forming quality was evaluated.The influence of printing current,forming speed,and contact pressure on the forming quality of the single-channel multilayer was analyzed.The optimal process parameters were obtained and the quality characterization of the experiment results was conducted.Results show that the printing current has the most significant influence on the forming quality of the single-channel multilayer.Under the optimal process parameters,the forming section is well fused and the surface is continuously smooth.The surface roughness of a single-channel 3-layer sample is 0.16μm,and the average Vickers hardness of cross section fusion zone is 317 HV,which lays a foundation for the subsequent use of Joule heat additive manufacturing technique to form thinwall parts. 展开更多
关键词 Joule heat additive manufacturing single-channel multilayer process parameter forming quality
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Multilayered microfluidic platform for three-dimensional vascularized organ-on-a-chip applications
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作者 Chenyang Zhou Zhangjie Li +3 位作者 Jiaqi Xu Dingyuan Yu Lian Xuan Xiaolin Wang 《Bio-Design and Manufacturing》 2025年第6期930-947,I0004-I0009,共24页
The vascular network is integral to the developmental and metabolic processes of various tissues and functions as a systemic circulatory system that also interconnects organs throughout the body.In this study,we descr... The vascular network is integral to the developmental and metabolic processes of various tissues and functions as a systemic circulatory system that also interconnects organs throughout the body.In this study,we describe a multilayered microfluidic organ-on-a-chip platform designed for reproducing various three-dimensional(3D)vascularized microtissue models for biological applications.This platform utilizes a porous membrane as a physical barrier and leverages capillary action for hydrogel self-filling.Its high flow resistance mitigates the risk of gel bursting into the medium channels and facilitates the delivery of substances to generate a wide range of interstitial flow and biochemical factor concentration gradients.This study demonstrated that this platform can be used to accurately replicate 3D microenvironments for vasculogenesis,angiogenesis,and vascularized tumor modeling.We also investigated the critical role of multiple microenvironmental regulations in vascular formation on a chip.Moreover,we reproduced the process of tumor angiogenesis,including primary solid tumor features and the inhibitory effects of antitumor drugs on tumor growth and tumor vasculature before and after angiogenesis.Hence,our multilayered microfluidic platform is valuable for exploring multiple vascular mechanisms and constructing specific microtissues that closely mimic in vivo physiological conditions,providing new strategies for cancer research.Furthermore,the multilayered configuration improves design flexibility and scalability,providing the potential for a multi-organ interconnected platform for high-throughput drug screening. 展开更多
关键词 Microfluidics multilayerED Organ-on-a-chip VASCULARIZATION
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Self-similarity of multilayer networks
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作者 Bing Wang Huizhi Yu Daijun Wei 《Chinese Physics B》 2025年第1期204-213,共10页
Research on the self-similarity of multilayer networks is scarce, when compared to the extensive research conducted on the dynamics of these networks. In this paper, we use entropy to determine the edge weights in eac... Research on the self-similarity of multilayer networks is scarce, when compared to the extensive research conducted on the dynamics of these networks. In this paper, we use entropy to determine the edge weights in each sub-network,and apply the degree–degree distance to unify the weight values of connecting edges between different sub-networks, and unify the edges with different meanings in the multilayer network numerically. At this time, the multilayer network is compressed into a single-layer network, also known as the aggregated network. Furthermore, the self-similarity of the multilayer network is represented by analyzing the self-similarity of the aggregate network. The study of self-similarity was conducted on two classical fractal networks and a real-world multilayer network. The results show that multilayer networks exhibit more pronounced self-similarity, and the intensity of self-similarity in multilayer networks can vary with the connection mode of sub-networks. 展开更多
关键词 multilayer networks SELF-siMILARITY degree-degree distance ENTROPY
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An epidemic model considering multiple factors based on multilayer hypernetworks
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作者 Yue-Yue Zheng Zhi-Ping Wang +2 位作者 Ya-Nan Sun Shi-Jie Xie Lin Wang 《Chinese Physics B》 2025年第10期271-283,共13页
The outbreak of COVID-19 in 2019 has made people pay more attention to infectious diseases.In order to reduce the risk of infection and prevent the spread of infectious diseases,it is crucial to strengthen individual ... The outbreak of COVID-19 in 2019 has made people pay more attention to infectious diseases.In order to reduce the risk of infection and prevent the spread of infectious diseases,it is crucial to strengthen individual immunization measures and to restrain the diffusion of negative information relevant to vaccines at the opportune moment.This study develops a three-layer coupling model within the framework of hypernetwork evolution,examining the interplay among negative information,immune behavior,and epidemic propagation.Firstly,the dynamic topology evolution process of hypernetwork includes node joining,aging out,hyperedge adding and reconnecting.The three-layer communication model accounts for the multifaceted influences exerted by official media channels,subjective psychological acceptance capabilities,self-identification abilities,and physical fitness levels.Each level of the decision-making process is described using the Heaviside step function.Secondly,the dynamics equations of each state and the prevalence threshold are derived using the microscopic Markov chain approach(MMCA).The results show that the epidemic threshold is affected by three transmission processes.Finally,through the simulation testing,it is possible to enhance the intensity of official clarification,improve individual self-identification ability and physical fitness,and thereby promote the overall physical enhancement of society.This,in turn,is beneficial in controlling false information,heightening vaccination coverage,and controlling the epidemic. 展开更多
关键词 multilayer hypernetworks information diffusion immunization behavior epidemic spreading
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Optimized graph neural network-multilayer perceptron fusion classifier for metastatic prostate cancer detection in Western and Asian populations
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作者 Fengxian Han Xiaohui Fan +12 位作者 Pengwei Long Wenhui Zhang Qiting Li Yingxuan Li Xingpeng Guo Yinran Luo Rongqi Wen Sheng Wang Shan Zhang Yizhuo Li Yan Wang Xu Gao Jing Li 《Asian Journal of Urology》 2025年第3期327-337,共11页
Objective:Prostate cancer(PCa)exhibits significant genomic differences between Western and Asian populations.This study aimed to design a predictive model applicable across diverse populations while selecting a limite... Objective:Prostate cancer(PCa)exhibits significant genomic differences between Western and Asian populations.This study aimed to design a predictive model applicable across diverse populations while selecting a limited set of genes suitable for clinical implementation.Methods:We utilized an integrated dataset of 1360 whole-exome and whole-genome sequences from Chinese and Western PCa cohorts to develop and evaluate the model.External validation was conducted using an independent cohort of patients.A graph neural network architecture,termed the pathway-aware multi-layered hierarchical network-Western and Asian(P-NETwa),was developed and trained on combined genomic profiles from Chinese and Western cohorts.The model employed a multilayer perceptron(MLP)to identify key signature genes from multiomics data,enabling precise prediction of PCa metastasis.Results:The model achieved an accuracy of 0.87 and an F1-score of 0.85 on Western population datasets.The application of integrated Chinese and Western population data improved the accuracy to 0.88,achieving an F1-score of 0.75.The analysis identified 18 signature genes implicated in PCa progression,including established markers(AR and TP53)and novel candidates(MUC16,MUC4,and ASB12).For clinical adoption,the model was optimized for commercially available gene panels while maintaining high classification accuracy.Additionally,a user-friendly web interface was developed to facilitate real-time prediction of primary versus metastatic status using the pre-trained P-NETwa-MLP model.Conclusion:The P-NETwa-MLP model integrates a query system that allows for efficient retrieval of prediction outcomes and associated genomic signatures via sample ID,enhancing its potential for seamless integration into clinical workflows. 展开更多
关键词 Prostate cancer Machine learning multilayer perceptron Graph neural network
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Effects of information and policy regulation on green behavior propagation in multilayer networks: Modeling, analysis,and optimal allocation
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作者 Xian-Li Sun Ling-Hua Zhang 《Chinese Physics B》 2025年第6期635-646,共12页
As the economy grows, environmental issues are becoming increasingly severe, making the promotion of green behavior more urgent. Information dissemination and policy regulation play crucial roles in influencing and am... As the economy grows, environmental issues are becoming increasingly severe, making the promotion of green behavior more urgent. Information dissemination and policy regulation play crucial roles in influencing and amplifying the spread of green behavior across society. To this end, a novel three-layer model in multilayer networks is proposed. In the novel model, the information layer describes green information spreading, the physical contact layer depicts green behavior propagation, and policy regulation is symbolized by an isolated node beneath the two layers. Then, we deduce the green behavior threshold for the three-layer model using the microscopic Markov chain approach. Moreover, subject to some individuals who are more likely to influence others or become green nodes and the limitations of the capacity of policy regulation, an optimal scheme is given that could optimize policy interventions to most effectively prompt green behavior.Subsequently, simulations are performed to validate the preciseness and theoretical results of the new model. It reveals that policy regulation can prompt the prevalence and outbreak of green behavior. Then, the green behavior is more likely to spread and be prevalent in the SF network than in the ER network. Additionally, optimal allocation is highly successful in facilitating the dissemination of green behavior. In practice, the optimal allocation strategy could prioritize interventions at critical nodes or regions, such as highly connected urban areas, where the impact of green behavior promotion would be most significant. 展开更多
关键词 green behavior propagation multilayer networks information dissemination optimal allocation
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Machine Learning Model for Wind Power Forecasting Using Enhanced Multilayer Perceptron
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作者 Ahmed A.Ewees Mohammed A.A.Al-Qaness +1 位作者 Ali Alshahrani Mohamed Abd Elaziz 《Computers, Materials & Continua》 2025年第5期2287-2303,共17页
Wind power forecasting plays a crucial role in optimizing the integration of wind energy into the grid by predicting wind patterns and energy output.This enhances the efficiency and reliability of renewable energy sys... Wind power forecasting plays a crucial role in optimizing the integration of wind energy into the grid by predicting wind patterns and energy output.This enhances the efficiency and reliability of renewable energy systems.Forecasting approaches inform energy management strategies,reduce reliance on fossil fuels,and support the broader transition to sustainable energy solutions.The primary goal of this study is to introduce an effective methodology for estimating wind power through temporal data analysis.This research advances an optimized Multilayer Perceptron(MLP)model using recently proposedmetaheuristic optimization algorithms,namely the FireHawk Optimizer(FHO)and the Non-Monopolize Search(NO).A modified version of FHO,termed FHONO,is developed by integrating NO as a local search mechanism to enhance the exploration capability and address the shortcomings of the original FHO.The developed FHONO is then employed to optimize the MLP for enhanced wind power prediction.The effectiveness of the proposed FHONO-MLP model is validated using renowned datasets from wind turbines in France.The results of the comparative analysis between FHONO-MLP,conventionalMLP,and other optimized versions of MLP show that FHONO-MLP outperforms the others,achieving an average RootMean Square Error(RMSE)of 0.105,Mean Absolute Error(MAE)of 0.082,and Coefficient of Determination(R^(2))of 0.967 across all datasets.These findings underscore the significant enhancement in predictive accuracy provided by FHONO and demonstrate its effectiveness in improving wind power forecasting. 展开更多
关键词 Wind power forecasting multilayer perceptron fire hawk optimizer non-monopolize search
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Matrix metalloproteinase-2 and pH-responsive drug eluting multilayer as intraocular lens coating to improve the posterior capsule opacification inhibition
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作者 Yuemei Han Jiahao Wang +1 位作者 Hao Chen Quankui Lin 《Regenerative Biomaterials》 2025年第6期183-194,共12页
Intraocular lens(IOL)is a crucial implant for cataract therapy.Posterior capsule opacification(PCO)is the most common post-operative complication after IOL implantation,which is the abnormal hyperplasia of the residua... Intraocular lens(IOL)is a crucial implant for cataract therapy.Posterior capsule opacification(PCO)is the most common post-operative complication after IOL implantation,which is the abnormal hyperplasia of the residual lens epithelial cells(LECs)after IOL implantation in cataract surgery.It is reported that the cellular microenvironment in the lens capsule changes after surgery,such as the elevated secretion of matrix metalloproteinases(MMPs)and a decrease in pH due to undesired cell proliferation.In this study,MMP-2and pH-triggered drug delivery polysaccharide multilayer coating was designed and introduced onto the IOL surface for obtaining the cellular microenvironment-sensitive drug-eluting intraocular implant.The methacrylated heparin(HEP-MA)was synthesized and used to layer-by-layer self-assemble with the doxorubicin-loaded chitosan nanoparticles on the IOL surface.The matrix metalloproteinase-2(MMP-2)sensitive peptide with cysteine contained in both ends(GCRD-GPQGIWGQ-DRCG)was then used to crosslink the polysaccharide multilayer via the Michael addition reaction between sulfhydryl group in cysteines and double bonds in methacrylate groups.The multilayer construction and subsequent cross-linking were validated through ultraviolet-visible spectrophotometer(UV-Vis)and Fourier transform infrared spectroscopy(FTIR).After modification,the IOL material surface becomes more hydrophilic while the optical properties were well maintained.The MMP-2 and pH-sensitive drug sustained-release coating were successfully obtained on the IOL surface via such design.The enzyme-triggered cell proliferation inhibition was realized in the in vitro experiments.In an animal model,significant up-regulation of MMP-2 was observed in the aqueous humor after cataract surgery.The multi-functionalized polysaccharide-coated IOL implanted in the animal eye via cataract surgery effectively inhibits PCO formation while it keeps good in viuo biosafety. 展开更多
关键词 posterior capsule opacifi cation intraocular lens STIMULI-RESPONsiVE drug-eluting coating polysaccharide multilayer
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Preparation and Characterization of Multilayered High-density Polyethylene with Tunable Crystalline Structure
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作者 Yi-Jie Ma Jia-Wei Gong +4 位作者 Bin Chen Ying Zhang Gan-Ji Zhong Zhong-Ming Li Xue-Qin Gao 《Chinese Journal of Polymer Science》 2025年第9期1616-1628,I0011,共14页
In rotationally extruded fittings,high-density polyethylene(HDPE)pipes prepared using conventional processing methods often suffer from poor pressure resistance and low toughness.This study introduces an innovative ro... In rotationally extruded fittings,high-density polyethylene(HDPE)pipes prepared using conventional processing methods often suffer from poor pressure resistance and low toughness.This study introduces an innovative rotary shear system(RSS)to address these deficiencies through controlled mandrel rotation and cooling rates.We successfully prepared self-reinforced HDPE pipes with a three-layer structure combining spherical and shish-kebab crystals.Rotational processing aligned the molecular chains in the ring direction and formed shish-kebab crystals.As a result,the annular tensile strength of the rotationally processed three-layer shish-kebab structure(TSK)pipe increased from 26.7 MPa to 76.3 MPa,an enhancement of 185.8%.Notably,while maintaining excellent tensile strength(73.4 MPa),the elongation at break of the spherulite shishkebab spherulite(SKS)tubes was improved to 50.1%,as compared to 33.8%in the case of shish-kebab spherulite shish-kebab(KSK)tubes.This improvement can be attributed to the changes in the micro-morphology and polymer structure within the SKS tubes,specifically due to the formation of small-sized shish-kebab crystals and the low degrees of interlocking.In addition,2D-SAXS analysis revealed that KSK tubes have higher tensile strength due to smaller crystal sizes and larger shish dimensions,forming dense interlocking structures.In contrast,the SKS and TSK tubes had thicker amorphous regions and smaller shish sizes,resulting in reduced interlocking and mechanical performance. 展开更多
关键词 High-density polyethylene pipe SHISH-KEBAB Circumferential tensile strength Rotational shear multilayer structure
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LOEV-APO-MLP:Latin Hypercube Opposition-Based Elite Variation Artificial Protozoa Optimizer for Multilayer Perceptron Training
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作者 Zhiwei Ye Dingfeng Song +7 位作者 Haitao Xie Jixin Zhang Wen Zhou Mengya Lei Xiao Zheng Jie Sun Jing Zhou Mengxuan Li 《Computers, Materials & Continua》 2025年第12期5509-5530,共22页
The Multilayer Perceptron(MLP)is a fundamental neural network model widely applied in various domains,particularly for lightweight image classification,speech recognition,and natural language processing tasks.Despite ... The Multilayer Perceptron(MLP)is a fundamental neural network model widely applied in various domains,particularly for lightweight image classification,speech recognition,and natural language processing tasks.Despite its widespread success,training MLPs often encounter significant challenges,including susceptibility to local optima,slow convergence rates,and high sensitivity to initial weight configurations.To address these issues,this paper proposes a Latin Hypercube Opposition-based Elite Variation Artificial Protozoa Optimizer(LOEV-APO),which enhances both global exploration and local exploitation simultaneously.LOEV-APO introduces a hybrid initialization strategy that combines Latin Hypercube Sampling(LHS)with Opposition-Based Learning(OBL),thus improving the diversity and coverage of the initial population.Moreover,an Elite Protozoa Variation Strategy(EPVS)is incorporated,which applies differential mutation operations to elite candidates,accelerating convergence and strengthening local search capabilities around high-quality solutions.Extensive experiments are conducted on six classification tasks and four function approximation tasks,covering a wide range of problem complexities and demonstrating superior generalization performance.The results demonstrate that LOEV-APO consistently outperforms nine state-of-the-art metaheuristic algorithms and two gradient-based methods in terms of convergence speed,solution accuracy,and robustness.These findings suggest that LOEV-APO serves as a promising optimization tool for MLP training and provides a viable alternative to traditional gradient-based methods. 展开更多
关键词 Artificial protozoa optimizer multilayer perceptron Latin hypercube sampling opposition-based learning neural network training
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Core-shell nickel@copper nanowires associated with multilayered gradient architecture design towards excellent absorption-dominant electromagnetic interference shielding
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作者 Peng Ai Xiaoping Mai +1 位作者 Bai Xue Lan Xie 《Journal of Materials Science & Technology》 2025年第27期21-31,共11页
Exploiting high-performance absorption-dominant electromagnetic interference(EMI)shielding composites is urgently desired yet challenging for minimizing secondary electromagnetic radiation pollution.Herein,a nickel(Ni... Exploiting high-performance absorption-dominant electromagnetic interference(EMI)shielding composites is urgently desired yet challenging for minimizing secondary electromagnetic radiation pollution.Herein,a nickel(Ni)shell was in-situ grown on a copper nanowires(CuNWs)core to greatly improve the stability of CuNWs,while maintaining excellent electrical conductivity.Afterward,Ni nanowires/Ni@Cu nanowires/graphite paper/waterborne polyurethane(NiNWs/Ni@CuNWs/graphite paper/WPU,n Ni-m Ni@Cu-G)composite foams with the multilayered gradient architectures were fabricated by a facile multi-step freeze-casting method.In the resultant composite foams,the lowly conductive porous NiNWs/WPU layer plays a role as the impedance matching layer,the moderately conductive porous Ni@CuNWs/WPU layer acts as the transition layer,and the highly conductive graphite paper layer serves as the reflection layer.Arising from the rational layout of multilayered gradient magnetic-electrical networks,n Ni-m Ni@Cu-G foam holds the superior averaged total EMI shielding effectiveness(EMI SET)of 75.2 dB and optimal absorption coefficient(A)of 0.93 at the incident direction from NiNWs/WPU layer,suggesting the dominant absorption in EMI shielding mechanism and efficiently alleviating the secondary electromagnetic pollution.Furthermore,n Ni-m Ni@Cu-G foam also exhibits fascinating compressive properties with a compressive strength of 49.3 kPa,which is essential for its practical application.This multilayered gradient architecture design provides valuable insight into high-efficiently constructing absorption-dominant EMI shielding composites. 展开更多
关键词 Core-shell structure multilayered gradient architecture Nickel@copper nanowire Absorption dominance Electromagnetic interference shielding
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An interfacial contact model for two-dimensional thermal consolidation of multilayered saturated soils subjected to ramp-type heating
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作者 WEN Min-jie TANG Ke-jie +6 位作者 XIE Jia-hao TIAN Yi ZHANG Yi-ming WU Wen-bing MEI Guo-xiong WU Da-zhi LIU Kai-fu 《Journal of Central South University》 2025年第9期3361-3382,共22页
When the interface of a multilayered saturated soil is rough with noticeable gaps, heat flow lines converge towards the actual contact points, causing thermal flow contraction. Conversely, in the interface between two... When the interface of a multilayered saturated soil is rough with noticeable gaps, heat flow lines converge towards the actual contact points, causing thermal flow contraction. Conversely, in the interface between two layers of soil with different properties, pore water flows slowly along the pore channels, demonstrating laminar flow phenomenon. To predict the thermal contact resistance and flow contact resistance at the interface, this paper constructs general imperfect thermal contact model and general imperfect flow contact model, respectively. Utilizing a thermo-hydro- mechanical coupling model, the thermal consolidation behavior of multilayered saturated soil under two-dimensional conditions is investigated. Fourier and Laplace transformations are applied to decouple the governing equations, yielding expressions for the temperature increment, pore water pressure, and displacement in multilayered saturated soil. The inverse Fourier-Laplace transformation is then used to obtain numerical solutions, which are compared with degeneration solutions to validate the computational accuracy. The differences in the thermal consolidation process under various thermal contact and flow contact resistance models are discussed. Furthermore, the impact of parameters such as the thermal resistance coefficient, partition thermal contact coefficient, flow contact resistance coefficient, and partition flow contact coefficient on thermal consolidation are investigated. Results indicate that thermal contact resistance creates a relative thermal gradient at the interface, leading to increased pore water pressure and reduced displacement nearby. In contrast, flow contact resistance generates a relative pore pressure gradient at the interface, resulting in increased displacement within the saturated soil with minimal effect on temperature increment distribution. 展开更多
关键词 multilayered saturated soils thermal consolidation thermal contact resistance flow contact resistance ramp-type heating
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Effect of Heat Treatment on Microstructure Evolution and Fracture Mechanism of 30CrMo/316L Multilayered Composites Fabricated by Vacuum Electron Beam Welding and Accumulative Hot Roll Bonding
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作者 Ming-Rong Fan Tian-Yu Wang +3 位作者 Jing-Gang Suo Ming-Kun Wang Ying-Ying Feng Zong-An Luo 《Acta Metallurgica Sinica(English Letters)》 2025年第12期2265-2278,共14页
The effects of accumulative hot rolling followed by solution treatment on the microstructural evolution and fracture behavior of 30CrMo/316L multilayered composites have been investigated.A scanning electron microscop... The effects of accumulative hot rolling followed by solution treatment on the microstructural evolution and fracture behavior of 30CrMo/316L multilayered composites have been investigated.A scanning electron microscope equipped with an electron backscatter diffraction probe,a laser confocal microscope,an electron probe microanalysis,and a universal testing machine were employed to characterize the microstructures and mechanical properties.The results indicate that solution treatment transformed the microstructure of the 30CrMo layer from ferrite to martensite,while the 316L layer remained austenitic but transitioned from the rolled to the recrystallized state.Additionally,solution treatment significantly enhanced the mechanical properties of the composite,leading to an increase in yield strength and ultimate tensile strength to 744 and 1106 MPa,respectively—258 and 276 MPa higher than those of the hot-rolled plate.The enhancement in strength is primarily attributed to the formation of high-strength martensite in the 30CrMo layer.During deformation,the composite interface effectively impeded crack propagation and induced step-like deflection.However,the formation of cross-layer grains facilitated crack nucleation at grain boundaries,leading to rapid crack propagation and instantaneous fracture.Therefore,preventing the formation of cross-layer grains during the heat treatment process is crucial,as their presence weakens the interfacial strengthening effect of the composite plate.This study provides valuable insights for the design and development of multi-layered steels. 展开更多
关键词 30CrMo/316L multilayered composite Accumulative rolling Solution treatment Microstructural evolution Fracture mechanism
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Perfluorocarbon liquid-assisted inverted multilayer internal limiting membrane flaps covering for macular hole retinal detachment in high myopia with axial length≥30 mm
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作者 Li-Ping Wang Wen-Jie Dang +3 位作者 Hong Yan Ke Gong Jin Deng Wen-Tao Sun 《International Journal of Ophthalmology(English edition)》 2025年第12期2288-2295,共8页
AIM:To evaluate the surgical outcomes of the perfluorocarbon liquid(PFCL)-assisted inverted multilayer internal limiting membrane(ILM)flaps covering technique in macular hole retinal detachment(MHRD)in high myopia wit... AIM:To evaluate the surgical outcomes of the perfluorocarbon liquid(PFCL)-assisted inverted multilayer internal limiting membrane(ILM)flaps covering technique in macular hole retinal detachment(MHRD)in high myopia with axial length(AL)≥30 mm.METHODS:In this retrospective,interventional,consecutive comparative study,44 MHRD eyes were divided into two groups:the PFCL-assisted inverted multilayer ILM flaps covering technique group(Group 1,21 eyes)and the ILM peeling group(Group 2,23 eyes).The follow-up period was>12mo.Postoperative outcomes,including retinal reattachment,macular hole(MH)closure,and bestcorrected visual acuity(BCVA),were assessed.Statistical analysis using the Mann–Whitney U test and Fisher’s exact test was conducted to compare differences between groups.RESULTS:There were no statistically significant differences in baseline preoperative clinical characteristics,including age,sex,AL,diopters,duration of symptom,lens status,posterior staphyloma presence and extent of RD.Retinal reattachment rates were higher in Group 1(90.5%)than in Group 2(82.6%),without statistical significance(P=0.667).MH closure rates were significantly higher in Group 1(85.7%)than in Group 2(17.4%;P<0.001).The Group-1 BCVA(logMAR)improved significantly from 2.13±0.91 preoperatively to 1.21±0.66 postoperatively(P=0.026).The Group 2 BCVA improved significantly from 1.91±0.53 preoperatively to 1.19±0.41 postoperatively(P=0.032).However,there were no significant differences in visual-acuity improvement between groups(P=0.460).CONCLUSION:This technique offers a more effective approach for improving MH closure rates and postoperative visual function in MHRD with AL≥30 mm in high myopia. 展开更多
关键词 high myopia inverted multilayer internal limiting membrane flaps covering macular hole retinal detachment perfluorocarbon liquid
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3D Exact Magneto-Electro-Elastic Static Analysis of Multilayered Plates
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作者 Salvatore Brischetto Domenico Cesare Tommaso Mondino 《Computer Modeling in Engineering & Sciences》 2025年第7期643-668,共26页
This study proposes a three-dimensional(3D)coupled magneto-electro-elastic problem for the static analysis of multilayered plates embedding piezomagnetic and piezoelectric layers by considering both sensor and actuato... This study proposes a three-dimensional(3D)coupled magneto-electro-elastic problem for the static analysis of multilayered plates embedding piezomagnetic and piezoelectric layers by considering both sensor and actuator configurations.The 3D governing equations for the magneto-electro-elastic static behavior of plates are explicitly show that are made by the three 3D equilibrium equations,the 3D divergence equation for magnetic induction,and the 3D divergence equation for the electric displacement.The proposed solution involves the exponential matrix in the thickness direction and primary variables’harmonic forms in the in-plane ones.A closed-form solution is performed considering simply-supported boundary conditions.Interlaminar continuity conditions are imposed for displacements,magnetic potential,electric potential,transverse shear/normal stresses,transverse normal magnetic induction and transverse normal electric displacement.Therefore,a layerwise approach is adopted.The results section is composed of an assessment part,where the present model is compared to past 3D electro-elastic or magneto-elastic formulations and a new benchmark part.Benchmarks consider sensor and actuator plate configurations for the fully coupled magneto-electro-elastic cases for different thickness ratios.Tabular and graphical results are presented for displacements,stresses,magnetic potential,electric potential,transverse normal magnetic induction and transverse normal electric displacement.For each presented benchmark,magneto-electro-elastic coupling and thickness and material layer effects are discussed in depth. 展开更多
关键词 multilayered and smart plates static analyses magneto-electro-elastic coupling exponential matrix method 3D model layer-wise approach
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Coaxial nano-multilayered C/SnO_(2)/TiO_(2) composites as anode materials for lithium-ion batteries
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作者 Jiao Li Haoran Liang +5 位作者 Shichao Li Jie Sun Yifan Zhang Shuxing Mei Shasha Wang Yong Zheng 《Rare Metals》 2025年第10期7118-7135,共18页
Tin dioxide(SnO_(2))with a high theoretical specific capacity of 1494 mAh g^(-1)is a promising candidate anode material for lithium storage.However,the shortcomings of serious volume expansion and low conductivity lim... Tin dioxide(SnO_(2))with a high theoretical specific capacity of 1494 mAh g^(-1)is a promising candidate anode material for lithium storage.However,the shortcomings of serious volume expansion and low conductivity limit its wide application.Herein,coaxial nano-multilayered C/SnO_(2)/TiO_(2)composites were fabricated via layerby-layer self-assembly of TiO_(2)and SnO_(2)-gel layers on the natural cellulose filter paper,followed by thermal treatment under a nitrogen atmosphere.Through engineering design of the assembly process,the optimal C/SinO_(2)/TiO_(2)composite features five alternating SnO_(2)and TiO_(2)nanolayers,with TiO_(2)as the outside shell(denoted as C/TSTST).This unique structure endows the C/TSTST with excellent structural stability and electrochemical kinetics,making it a high-performance anode for lithium-ion batteries(LIBs).The C/TSTST composite delivers a high reversible capacity of 676 mAh g^(-1)at 0.1 A g^(-1)after 200 cycles and retains a capacity of 504 mAh g^(-1)at 1.0 A g^(-1),which can be recovered to 781 mAh g^(-1)at 0.1 A g^(-1)The significantly enhanced electrochemical performance is attributed to the hierarchical hybrid structure,where the carbon core combined with coaxial TiO_(2)nanolayers serves as a structural scaffold,ameliorating volume change of SnO_(2)while creating abundant interfacial defects for enhanced lithium storage and rapid charge transport.These findings are further demonstrated by the density functional theory(DFT)calculations.This work provides an efficient strategy for designing coaxial nano-multilayered transition metal oxide-related electrode materials,offering new insights into high-performance LIBs anodes. 展开更多
关键词 C/SnO_(2)/TiO_(2) Coaxial multilayered structure Layer-by-layer self-assembly Anode materials Lithium storage
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C/SiC/MoSi_2-SiC-Si multilayer coating for oxidation protection of carbon/carbon composites 被引量:5
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作者 张雨雷 李贺军 +2 位作者 胡志雄 李克智 张磊磊 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期2118-2122,共5页
C/SiC/MoSi2-SiC-Si oxidation protective multilayer coating for carbon/carbon (C/C) composites was prepared by pack cementation and slurry method. The microstructure, element distribution and phase composition of the... C/SiC/MoSi2-SiC-Si oxidation protective multilayer coating for carbon/carbon (C/C) composites was prepared by pack cementation and slurry method. The microstructure, element distribution and phase composition of the as-received coating were analyzed by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The results show that the multilayer coating was composed of MoSi2, SiC and Si. It could effectively protect C/C composites against oxidation for 200 h with the mass loss of 3.25% at 1873 K in static air. The mass loss of the coated C/C composites results from the volatilization of SiO2 and the formation of cracks and bubble holes in the coating. 展开更多
关键词 C/C composites C/siC MOsi2 siC multilayer COATING OXIDATION
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Structure and mechanical properties of thick Cr/Cr_2N/CrN multilayer coating deposited by multi-arc ion plating 被引量:9
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作者 单磊 王永欣 +3 位作者 李金龙 李赫 鲁侠 陈建敏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第4期1135-1143,共9页
A Cr/Cr2N/CrN multilayer coating with a thickness of 24.4 μm was deposited by multi-arc ion plating. The coating was systematically characterized by field emission scanning electron microscopy(FESEM), X-ray photoelec... A Cr/Cr2N/CrN multilayer coating with a thickness of 24.4 μm was deposited by multi-arc ion plating. The coating was systematically characterized by field emission scanning electron microscopy(FESEM), X-ray photoelectron spectrometry(XPS), energy dispersive spectroscopy(EDS), X-ray diffraction(XRD) and transmission electron microscopy(TEM). Hardness and adhesion were tested by nanoindentation and scratch tester, respectively. The friction properties were investigated by a reciprocating UMT-3MT ball-on-disk tribometer in air and seawater. The results showed that the multilayer coating consisted of three different layers, with Cr,Cr2N and CrN phases, respectively. Compared with CrN single layer coating, the adhesion of the multilayer coating was improved significantly, the hardness of the multilayer coating was(21±2) GPa. The corrosion resistance of the multilayer coating was also improved in artificial seawater. The friction coefficient of multilayer coating was lower than that of CrN single layer coating both in air and seawater. 展开更多
关键词 Cr/Cr2N/CrN multilayer coating microstructure mechanical properties corrosion resistance FRICTION
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