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Effect of dominant fractures on triaxial behavior of 3D-printed rock analogs with internal fracture networks
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作者 Lishuai Jiang Pimao Li +3 位作者 Xin He Yang Zhao Quansen Wu Ye Zhao 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1390-1412,共23页
Internal structural defects in engineering rock masses vary in size,exhibit complex shapes,and are unevenly distributed.Dominant fractures within a rock mass often play a critical to its mechanical behavior,directly a... Internal structural defects in engineering rock masses vary in size,exhibit complex shapes,and are unevenly distributed.Dominant fractures within a rock mass often play a critical to its mechanical behavior,directly affecting the macromechanical properties and failure modes.These fractures affect the instability and failure of the surrounding rock,significantlyimpacting the overall stability of engineering structures.Herein,sand-powder three-dimensional(3D)printing technology was used to prepare rock-like specimens with internal fracture networks.Triaxial compression testing,post-failure fracture mapping,and fractal dimension analysis of the fracture surfaces were conducted to investigate the effects of dominant fracture angles on the strength and deformation of rocks with internal fracture networks under triaxial stress.The results indicate that the dominant fracture angle has a pronounced effect on the mechanical behavior of rock.With increasing angle,both compressive strength and elastic modulus exhibit an initial decline followed by an increase.Moreover,higher confiningpressure significantlyimproves the compressive strength of fractured rock.This enhancement weakens as the confiningpressure further increases.Moreover,with increasing confiningpressure,the differences between the maximum and minimum values of elastic moduli and lateral strain ratios in fractured rock gradually decrease.Thus,the impact of the dominant fracture angle on rock mass deformation decreases with increasing confiningpressure.This research elucidates the effects of dominant fracture angles on the mechanical and failure properties of complex fractured rock masses and the influenceof the confiningpressure on these relationships.It provides valuable theoretical insights and practical guidance for stability analyses in engineering rock masses. 展开更多
关键词 Sand powder three-dimensional(3D) printing Internal fracture networks Triaxial compression Rock mechanics Fractal dimension
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Generation of SARS-CoV-2 dual-target candidate inhibitors through 3D equivariant conditional generative neural networks 被引量:1
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作者 Zhong-Xing Zhou Hong-Xing Zhang Qingchuan Zheng 《Journal of Pharmaceutical Analysis》 2025年第6期1291-1310,共20页
Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)mutations are influenced by random and uncontrollable factors,and the risk of the next widespread epidemic remains.Dual-target drugs that synergistically act ... Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)mutations are influenced by random and uncontrollable factors,and the risk of the next widespread epidemic remains.Dual-target drugs that synergistically act on two targets exhibit strong therapeutic effects and advantages against mutations.In this study,a novel computational workflow was developed to design dual-target SARS-CoV-2 candidate inhibitors with the Envelope protein and Main protease selected as the two target proteins.The drug-like molecules of our self-constructed 3D scaffold database were used as high-throughput molecular docking probes for feature extraction of two target protein pockets.A multi-layer perceptron(MLP)was employed to embed the binding affinities into a latent space as conditional vectors to control conditional distribution.Utilizing a conditional generative neural network,cG-SchNet,with 3D Euclidean group(E3)symmetries,the conditional probability distributions of molecular 3D structures were acquired and a set of novel SARS-CoV-2 dual-target candidate inhibitors were generated.The 1D probability,2D joint probability,and 2D cumulative probability distribution results indicate that the generated sets are significantly enhanced compared to the training set in the high binding affinity area.Among the 201 generated molecules,42 molecules exhibited a sum binding affinity exceeding 17.0 kcal/mol while 9 of them having a sum binding affinity exceeding 19.0 kcal/mol,demonstrating structure diversity along with strong dual-target affinities,good absorption,distribution,metabolism,excretion,and toxicity(ADMET)properties,and ease of synthesis.Dual-target drugs are rare and difficult to find,and our“high-throughput docking-multi-conditional generation”workflow offers a wide range of options for designing or optimizing potent dual-target SARS-CoV-2 inhibitors. 展开更多
关键词 SARS-CoV-2 Dual-target drug 3D generative neural networks Drug design
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3D tomographic analysis of equatorial plasma bubble using GNSS-TEC data from Indonesian GNSS Network
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作者 Ihsan Naufal Muafiry Prayitno Abadi +5 位作者 Teguh N.Pratama Dyah R.Martiningrum Sri Ekawati Yuandhika GWismaya Febrylian FChabibi Gatot HPramono 《Earth and Planetary Physics》 EI CAS 2025年第1期127-136,共10页
Equatorial Plasma Bubbles(EPBs)are ionospheric irregularities that take place near the magnetic equator.EPBs most commonly occur after sunset during the equinox months,although they can also be observed during other s... Equatorial Plasma Bubbles(EPBs)are ionospheric irregularities that take place near the magnetic equator.EPBs most commonly occur after sunset during the equinox months,although they can also be observed during other seasons.The phenomenon significantly disrupts radio wave signals essential to communication and navigation systems.The national network of Global Navigation Satellite System(GNSS)receivers in Indonesia(>30°longitudinal range)provides an opportunity for detailed EPB studies.To explore this,we conducted preliminary 3D tomography of total electron content(TEC)data captured by GNSS receivers following a geomagnetic storm on December 3,2023,when at least four EPB clusters occurred in the Southeast Asian sector.TEC and extracted TEC depletion with a 120-minute running average were then used as inputs for a 3D tomography program.Their 2D spatial distribution consistently captured the four EPB clusters over time.These tomography results were validated through a classical checkerboard test and comparisons with other ionospheric data sources,such as the Global Ionospheric Map(GIM)and International Reference Ionosphere(IRI)profile.Validation of the results demonstrates the capability of the Indonesian GNSS network to measure peak ionospheric density.These findings highlight the potential for future three-dimensional research of plasma bubbles in low-latitude regions using existing GNSS networks,with extensive longitudinal coverage. 展开更多
关键词 EPB Indonesian GNSS network 3D tomography
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Modeling and Comprehensive Review of Signaling Storms in 3GPP-Based Mobile Broadband Networks:Causes,Solutions,and Countermeasures
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作者 Muhammad Qasim Khan Fazal Malik +1 位作者 Fahad Alturise Noor Rahman 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期123-153,共31页
Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important a... Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important and scarce network resources such as bandwidth and processing power.There have been several reports of these control signaling turning into signaling storms halting network operations and causing the respective Telecom companies big financial losses.This paper draws its motivation from such real network disaster incidents attributed to signaling storms.In this paper,we present a thorough survey of the causes,of the signaling storm problems in 3GPP-based mobile broadband networks and discuss in detail their possible solutions and countermeasures.We provide relevant analytical models to help quantify the effect of the potential causes and benefits of their corresponding solutions.Another important contribution of this paper is the comparison of the possible causes and solutions/countermeasures,concerning their effect on several important network aspects such as architecture,additional signaling,fidelity,etc.,in the form of a table.This paper presents an update and an extension of our earlier conference publication.To our knowledge,no similar survey study exists on the subject. 展开更多
关键词 Signaling storm problems control signaling load analytical modeling 3GPP networks smart devices diameter signaling mobile broadband data access data traffic mobility management signaling network architecture 5G mobile communication
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3D bioprinted unidirectional neural network and its application for alcoholic neurodegeneration
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作者 Mihyeon Bae Joeng Ju Kim +1 位作者 Jinah Jang Dong-Woo Cho 《International Journal of Extreme Manufacturing》 2025年第5期294-312,共19页
The brain exhibits complex physiology characterized by unique features such as a brain-specific extracellular matrix, compartmentalized structure (white and grey matter), and an aligned axonal network. These physiolog... The brain exhibits complex physiology characterized by unique features such as a brain-specific extracellular matrix, compartmentalized structure (white and grey matter), and an aligned axonal network. These physiological characteristics underpin brain function and facilitate signal transduction similar to that in an electrical circuit. Therefore, investigating these features in vitro is crucial for understanding the interactions between neuronal signal transduction processes and the pathology of neurological diseases. Compared to neurons on patterned substrates, three-dimensional (3D) bioprinting-based neural models provide significant advantages in replicating axonal kinetics without physical limitations. This study proposes the development of a 3D bioprinted engineered neural network (BENN) model to replicate the physiological features of the brain, suggesting its application as a tool for studying neurodegenerative diseases. We employed 3D bioprinting to reconstruct the compartmentalized structure of the brain, and controlled the directionality of axonal growth by applying electrical stimuli to the printed neural structure for overcoming spatial constraints. The reconstructed axonal network demonstrated reliability as a neural analog, including the visualization of mature neuronal features and spontaneous calcium reactions. Furthermore, these brain-like neural network models have demonstrated usefulness for studying neurodegeneration by enabling the visualization of degenerative pathophysiology in alcohol-exposed neurons. The BENN facilitates the visualization of region-specific pathological markers in soma or axon populations, including amyloid-beta formation and axonal deformation. Overall, the BENN closely mimics brain physiology, offers insights into the dynamics of axonal networks, and can be applied to studying neurological diseases. 展开更多
关键词 3D bioprinting engineered neural network NEURODEGENERATION
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Fusion Prototypical Network for 3D Scene Graph Prediction
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作者 Jiho Bae Bogyu Choi +1 位作者 Sumin Yeon Suwon Lee 《Computer Modeling in Engineering & Sciences》 2025年第6期2991-3003,共13页
Scene graph prediction has emerged as a critical task in computer vision,focusing on transforming complex visual scenes into structured representations by identifying objects,their attributes,and the relationships amo... Scene graph prediction has emerged as a critical task in computer vision,focusing on transforming complex visual scenes into structured representations by identifying objects,their attributes,and the relationships among them.Extending this to 3D semantic scene graph(3DSSG)prediction introduces an additional layer of complexity because it requires the processing of point-cloud data to accurately capture the spatial and volumetric characteristics of a scene.A significant challenge in 3DSSG is the long-tailed distribution of object and relationship labels,causing certain classes to be severely underrepresented and suboptimal performance in these rare categories.To address this,we proposed a fusion prototypical network(FPN),which combines the strengths of conventional neural networks for 3DSSG with a Prototypical Network.The former are known for their ability to handle complex scene graph predictions while the latter excels in few-shot learning scenarios.By leveraging this fusion,our approach enhances the overall prediction accuracy and substantially improves the handling of underrepresented labels.Through extensive experiments using the 3DSSG dataset,we demonstrated that the FPN achieves state-of-the-art performance in 3D scene graph prediction as a single model and effectively mitigates the impact of the long-tailed distribution,providing a more balanced and comprehensive understanding of complex 3D environments. 展开更多
关键词 3D scene graph prediction prototypical network 3D scene understanding
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Effectiveness of Invertible Neural Network in Variable Material 3D Printing:Application to Screw-Based Material Extrusion
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作者 Yunze Wang Beining Zhang +5 位作者 Siwei Lu Chuncheng Yang Ling Wang Jiankang He Changning Sun Dichen Li 《Additive Manufacturing Frontiers》 2025年第2期20-29,共10页
Variable material screw-based material extrusion(S-MEX)3D printing technology provides a novel approach for fabricating composites with continuous material gradients.Nevertheless,achieving precise alignment between th... Variable material screw-based material extrusion(S-MEX)3D printing technology provides a novel approach for fabricating composites with continuous material gradients.Nevertheless,achieving precise alignment between the process parameters and material compositions is challenging because of fluctuations in the melt rheological state caused by material variations.In this study,an invertible extrusion prediction model for 0-40 wt% short carbon fiber reinforced polyether-ether-ketone(SCF/PEEK)in the S-MEX process was established using an invertible neural network(INN)that demonstrated the capabilities of forward flow rate prediction and inverse process optimization with accuracies of 0.852 and 0.877,respectively.Moreover,a strategy for adjusting the screw speeds using process parameters obtained from the INN was developed to maintain a consistent flow rate during the variable material printing process.Benefiting from uniform flow,the linewidth accuracy was improved by 77%,and the surface roughness was reduced by 51%.Adjusting the process parameters by using an INN offers significant potential for flow rate control and the enhancement of the overall performance of variable material 3D printing. 展开更多
关键词 Material extrusion 3D printing Multi-material Invertible neural network
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Prediction of Quality Markers(Q-Markers)for the Mongolian Medicine Naru-3 Based on Chemical Composition,Pharmacological Effects,and Network Pharmacology
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作者 Ying En Liang Xu Jiaqi Yu 《Journal of Clinical and Nursing Research》 2025年第1期1-10,共10页
Naru Sanwei Pill,also known as Naru-3,a Mongolian medicine originating from Zhigao Pharmacopoeia,is a classic prescription used in the treatment of rheumatism.It is composed of Terminalia chebula,processed Aconitum ku... Naru Sanwei Pill,also known as Naru-3,a Mongolian medicine originating from Zhigao Pharmacopoeia,is a classic prescription used in the treatment of rheumatism.It is composed of Terminalia chebula,processed Aconitum kusnezoffii Reichb.,and Piper longum,and is known for its effects in eliminating“mucus,”relieving pain,and reducing swelling,with significant efficacy in treating joint effusion and lumbar pain.In recent years,researchers have summarized its chemical components and pharmacological effects,and employed network pharmacology methods based on the core theory of Traditional Chinese Medicine quality markers(Q-Markers)to analyze and predict its markers.The results identified potential Q-Markers for Naru-3,providing a scientific basis for quality control and further research. 展开更多
关键词 Mongolian medicine Naru-3 network pharmacology Quality markers Chemical components Pharmacological effects
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基于机器学习的西安市2018—2020年O_(3)浓度预测
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作者 刘南健 周卫健 李国辉 《地球环境学报》 2026年第1期116-127,共12页
臭氧(O_(3))浓度受自然因素和人类活动影响,呈现复杂的非线性演化特征,准确预测其浓度对环境管理和决策至关重要。文章以西安市为对象,利用2018—2020年逐小时空气污染物数据及同期ERA5气象再分析资料,构建卷积神经网络(CNN)、极端梯度... 臭氧(O_(3))浓度受自然因素和人类活动影响,呈现复杂的非线性演化特征,准确预测其浓度对环境管理和决策至关重要。文章以西安市为对象,利用2018—2020年逐小时空气污染物数据及同期ERA5气象再分析资料,构建卷积神经网络(CNN)、极端梯度提升机(XGBoost)、随机森林(RF)和多元线性回归(MLR) 4种模型,进行24 h单步O_(3)浓度预测。结果表明:基于树结构的XGBoost和RF模型整体预测性能优异,尤其在2020年全时段和该年夏季预测中表现突出,其中,XGBoost效果最佳;相比之下,经典的CNN模型并未展现出预期优势,而MLR模型在2020年及该年夏季预测中表现最差。所有模型对O_(3)浓度预测均存在一定程度的高估与低估,特别是对下午时段较高浓度的O_(3)浓度普遍低估,但树模型(XGBoost和RF)能更好地控制预测偏差幅度。进一步通过SHAP值解释2020年预测结果,发现历史O_(3)浓度、太阳辐射(SOL)和气压(PRS)是影响模型输出的前三大关键特征;在2020年的夏季预测中,O_(3)浓度和辐射相关因子对模型决策贡献尤为显著。研究表明树集成模型在处理O_(3)浓度预测的非线性特征时更具优势,为相关区域空气质量预报提供有效技术参考。 展开更多
关键词 O_(3)浓度预测 机器学习 基于树的模型 神经网络
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A lignin-based polyelectrolyte with fast 3D Li^(+)transportation network
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作者 Pengfei Sun Yeqiang Zhang +4 位作者 Chengdong Fang Jinji Lan Yanping Chen Liubin Feng Jiajia Chen 《Journal of Energy Chemistry》 2025年第8期114-121,共8页
In this work,we have developed a lignin-derived polymer electrolyte(LSELi),which demonstrates exceptional ionic conductivity of 1.6×10^(-3)S cm^(−1)and a high cation transference number of 0.57 at 25°C.Time ... In this work,we have developed a lignin-derived polymer electrolyte(LSELi),which demonstrates exceptional ionic conductivity of 1.6×10^(-3)S cm^(−1)and a high cation transference number of 0.57 at 25°C.Time of flight secondary ion mass spectrometry(TOF-SIMS)analysis shows that the large-size 1-ethyl-3-methylimidazolium cations(EMIM^(+))can induce the aggregation of the anionic segments in lignosulfonate to reconstruct the three-dimensional(3D)spatial structure of polyelectrolyte,thereby forming a fluent Li^(+)transport 3D network.Dielectric loss spectroscopy further reveals that within this transport network,Li^(+)transport is decoupled from the relaxation of lignosulfonate chain segments,exhibiting characteristics of rapid Li^(+)transport.Furthermore,in-situ distribution of relaxation times analysis indicates that a stable solid electrolyte interface layer is formed at the Li plating interface with LSELi,optimizing the Li plating interface and exhibiting low charge transfer impedance and stable Li plating and stripping.Thus,a substantially prolonged cycling stability and reversibility are obtained in the Li||LSELi||Li battery at 25°C(1800 h at 0.1 mA cm^(−2),0.1 mAh cm^(−2)).At 25°C,the Li||LSELi||LiFePO_(4)cell shows 132 mAh g^(−1)of capacity with 92.7%of retention over 120 cycles at 0.1 mA cm^(−2). 展开更多
关键词 Lithium metal batteries Lignin-based polyelectrolyte 3D Li^(+)transportation network Rechargeable batteries
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Adaptive Fusion Neural Networks for Sparse-Angle X-Ray 3D Reconstruction
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作者 Shaoyong Hong Bo Yang +4 位作者 Yan Chen Hao Quan Shan Liu Minyi Tang Jiawei Tian 《Computer Modeling in Engineering & Sciences》 2025年第7期1091-1112,共22页
3D medical image reconstruction has significantly enhanced diagnostic accuracy,yet the reliance on densely sampled projection data remains a major limitation in clinical practice.Sparse-angle X-ray imaging,though safe... 3D medical image reconstruction has significantly enhanced diagnostic accuracy,yet the reliance on densely sampled projection data remains a major limitation in clinical practice.Sparse-angle X-ray imaging,though safer and faster,poses challenges for accurate volumetric reconstruction due to limited spatial information.This study proposes a 3D reconstruction neural network based on adaptive weight fusion(AdapFusionNet)to achieve high-quality 3D medical image reconstruction from sparse-angle X-ray images.To address the issue of spatial inconsistency in multi-angle image reconstruction,an innovative adaptive fusion module was designed to score initial reconstruction results during the inference stage and perform weighted fusion,thereby improving the final reconstruction quality.The reconstruction network is built on an autoencoder(AE)framework and uses orthogonal-angle X-ray images(frontal and lateral projections)as inputs.The encoder extracts 2D features,which the decoder maps into 3D space.This study utilizes a lung CT dataset to obtain complete three-dimensional volumetric data,from which digitally reconstructed radiographs(DRR)are generated at various angles to simulate X-ray images.Since real-world clinical X-ray images rarely come with perfectly corresponding 3D“ground truth,”using CT scans as the three-dimensional reference effectively supports the training and evaluation of deep networks for sparse-angle X-ray 3D reconstruction.Experiments conducted on the LIDC-IDRI dataset with simulated X-ray images(DRR images)as training data demonstrate the superior performance of AdapFusionNet compared to other fusion methods.Quantitative results show that AdapFusionNet achieves SSIM,PSNR,and MAE values of 0.332,13.404,and 0.163,respectively,outperforming other methods(SingleViewNet:0.289,12.363,0.182;AvgFusionNet:0.306,13.384,0.159).Qualitative analysis further confirms that AdapFusionNet significantly enhances the reconstruction of lung and chest contours while effectively reducing noise during the reconstruction process.The findings demonstrate that AdapFusionNet offers significant advantages in 3D reconstruction of sparse-angle X-ray images. 展开更多
关键词 3D reconstruction adaptive fusion X-ray imaging medical imaging deep learning neural networks sparse angles autoencoder
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Polymerized-ionic-liquid-based solid polymer electrolyte for ultra-stable lithium metal batteries enabled by structural design of monomer and crosslinked 3D network
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作者 Lingwang Liu Jiangyan Xue +14 位作者 Yiwen Gao Shiqi Zhang Haiyang Zhang Keyang Peng Xin Zhang Suwan Lu Shixiao Weng Haifeng Tu Yang Liu Zhicheng Wang Fengrui Zhang Daosong Fu Jingjing Xu Qun Luo Xiaodong Wu 《Materials Reports(Energy)》 2025年第1期61-69,共9页
Solid polymer electrolytes(SPEs)have attracted much attention for their safety,ease of packaging,costeffectiveness,excellent flexibility and stability.Poly-dioxolane(PDOL)is one of the most promising matrix materials ... Solid polymer electrolytes(SPEs)have attracted much attention for their safety,ease of packaging,costeffectiveness,excellent flexibility and stability.Poly-dioxolane(PDOL)is one of the most promising matrix materials of SPEs due to its remarkable compatibility with lithium metal anodes(LMAs)and suitability for in-situ polymerization.However,poor thermal stability,insufficient ionic conductivity and narrow electrochemical stability window(ESW)hinder its further application in lithium metal batteries(LMBs).To ameliorate these problems,we have successfully synthesized a polymerized-ionic-liquid(PIL)monomer named DIMTFSI by modifying DOL with imidazolium cation coupled with TFSI^(-)anion,which simultaneously inherits the lipophilicity of DOL,high ionic conductivity of imidazole,and excellent stability of PILs.Then the tridentate crosslinker trimethylolpropane tris[3-(2-methyl-1-aziridine)propionate](TTMAP)was introduced to regulate the excessive Li^(+)-O coordination and prepare a flame-retardant SPE(DT-SPE)with prominent thermal stability,wide ESW,high ionic conductivity and abundant Lit transference numbers(t_(Li+)).As a result,the LiFePO_(4)|DT-SPE|Li cell exhibits a high initial discharge specific capacity of 149.60 mAh g^(-1)at 0.2C and 30℃with a capacity retention rate of 98.68%after 500 cycles.This work provides new insights into the structural design of PIL-based electrolytes for long-cycling LMBs with high safety and stability. 展开更多
关键词 Polymerized ionic liquid Solid polymer electrolyte Structural design Crosslinked 3D network Lithium metal battery
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Assembling 3D cross-linked network by carbon nitride nanowires for visible-light photocatalytic H_(2) evolution from dyestuffs wastewater
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作者 Linyu Zhu Xu Tian +5 位作者 Guang Shi Wenchi Zhang Peisong Tang Mohamed Bououdina Sajjad Ali Pengfei Xia 《Chinese Chemical Letters》 2025年第12期561-566,共6页
Photocatalytic H_(2) evolution from wastewater exhibits fascinating prospects in environment and energy fields.Here,we propose a novel 3D cross-linked g-C_(3)N_(4) network(SCN)assembling with 1D nanowires.This network... Photocatalytic H_(2) evolution from wastewater exhibits fascinating prospects in environment and energy fields.Here,we propose a novel 3D cross-linked g-C_(3)N_(4) network(SCN)assembling with 1D nanowires.This network structure endows SCN with abundant carbon defects,creating a defect energy level and shallow charge trapping centres,which significantly prolongs the photocarrier lifetime,suppresses their recombination and facilitates the mass transfer process during the dye photodegradation.Consequently,in photocatalytic H_(2) evolution coupled with Rhodamine B(RhB)photodegradation under visible light,the H_(2) production rate of SCN is 283μmol h^(-1)g^(-1),accompanying by 97%RhB photodegradation efficiency,much higher than UCN's 31μmol h^(-1)g^(-1)and 64%.In particular,AQY of SCN for H_(2) evolution from RhB solution reaches 23.7%at 380 nm.Furthermore,the calculated transition states demonstrate that the N1 site connected to the defect in SCN has a minimum Gibbs free energy ΔG(H^(*)),indicating that H~+undergoes an H^(+)→H^(*)→H_(2) evolution process. 展开更多
关键词 Photocatalysis Carbon nitride 3D cross-linked network H_(2)evolution from wastewater Reaction mechanism
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Actuator Fault Diagnosis of 3-PR(P)S Parallel Robot Based on Dung Beetle Optimization-Back Propagation Neural Network
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作者 Junjie Huang Chenhao Huangfu +3 位作者 Qinlei Zhang Shikai Li Yonggang Yan Jiangkun Cai 《Journal of Dynamics, Monitoring and Diagnostics》 2025年第2期91-100,共10页
Any malfunctions of the actuators of the robots have the potential to destroy the robot’s normal motion,and most of the current actuator fault diagnosis methods are difficult to meet the requirements of simplifying t... Any malfunctions of the actuators of the robots have the potential to destroy the robot’s normal motion,and most of the current actuator fault diagnosis methods are difficult to meet the requirements of simplifying the actuator modeling and solving the difficulty of fault data collection.To solve the problem of real-time diagnosis of actuator faults in the 3-PR(P)S parallel robot,the model of 3-PR(P)S parallel robot and data-driven-based method for the fault diagnosis are presented.Firstly,only the input-output relationship of the actuator is considered for modeling actuator faults,reducing the complexity of fault modeling and reducing the time consumption of parameter identification,thereby meeting the requirements of real-time diagnosis.A Simulink model of the electromechanical actuator(EMA)was constructed to analyze actuator faults.Then the short-term analysis method was employed for collecting the sample data of the slider position on the test platform of the EMA system and feature extraction.Training samples for neural networks are obtained.Furthermore,we optimized the Back Propagation(BP)neural network using the Dung Beetle Optimization Algorithm(DBO),which effectively resolved the weights and thresholds of the BP neural network.Compared to BP and Particle Swarm Optimization(PSO)-BP,the DBO-BP has better convergence,convergence rate,and the best-classifying quality.So,the classification for the different actuator faults is obviously improved.Finally,a fault diagnosis system was designed for the actuator of the 3-PR(P)S parallel robot,and the experimental results demonstrate that this system can detect actuator faults within 0.1 seconds.This work also provides the technical support for the fault-tolerant control of the 3-PR(P)S Parallel robot. 展开更多
关键词 ACTUATOR Back Propagation neural network Dung Beetle Algorithm fault diagnosis 3-PR(P)S parallel robot
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长三角地区PM_(2.5)和O_(3)健康风险及其联防联控分区研究
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作者 宋晓伟 韩越梅 +5 位作者 郝永佩 程鹏 朱晓东 孔媛 高宁馨 李思思 《环境科学研究》 北大核心 2026年第2期493-505,共13页
为评估长三角地区PM_(2.5)和O_(3)短期暴露的健康风险,并破解区域复合污染联防联控精准分区管理的难题,本文分析了2015−2023年长三角地区PM_(2.5)和O_(3)污染特征及其健康风险,并通过量化复合污染健康指数(CPHI),构建了以城市为节点、... 为评估长三角地区PM_(2.5)和O_(3)短期暴露的健康风险,并破解区域复合污染联防联控精准分区管理的难题,本文分析了2015−2023年长三角地区PM_(2.5)和O_(3)污染特征及其健康风险,并通过量化复合污染健康指数(CPHI),构建了以城市为节点、以城市间复合污染的相似性为权重的复杂网络,同时应用Girvan-Newman社区发现算法(GN算法)划分联防联控分区,并在各分区内识别关键城市节点以支撑分区内差异化协同治理。结果表明:①得益于近年来大气污染治理成效显著,2015−2023年长三角地区PM_(2.5)年均浓度下降38.31%;而O_(3)年均浓度波动上升11.15%,主要与前期防控重点差异及新型冠状病毒感染疫情影响有关。PM_(2.5)与O_(3)的浓度峰值分别出现在冬季(62μg/m^(3))和夏季(117μg/m^(3)),二者峰值差异由不同的人为活动与自然因素共同驱动。PM_(2.5)与O_(3)污染严重区域均集中在长三角北部地区,南部地区污染较低。②2015−2023年长三角地区归因于PM_(2.5)污染的早逝人数显著下降,无锡市等城市降幅(66%)较大,而归因于O_(3)污染的早逝人数波动上升,芜湖市等城市增幅(25791%)较大。③基于GN算法的社区划分结果,将长三角地区划分为5个复合污染特征相似的联防联控区(北部分区、中西分区、中东分区、西南分区和东南分区)。各分区关键城市节点的差异化治理策略为,无锡市、嘉兴市等关键通道城市强化跨市协同治理,无锡市、苏州市等高效枢纽城市可率先实施减排示范,而滁州市、六安市等边缘城市应聚焦本地源治理。研究显示,长三角地区PM_(2.5)和O_(3)污染特征及健康风险具有明显的时空分异特征,且基于城市间CPHI时间序列所划分的联防联控分区及其关键节点识别,可为长三角地区精细化协同治理提供科学的决策依据。 展开更多
关键词 PM_(2.5) O_(3) 长三角地区 健康风险 复杂网络 区域联防联控
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基于GF-3雷达数据极化分解与深度学习的干旱区绿洲土地覆被及盐渍化分级研究
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作者 刘翔宇 张飞 依力亚斯江·努尔麦麦提 《新疆师范大学学报(自然科学版)》 2026年第2期58-70,共13页
土地利用/覆被演变研究是解析人地关系的重要科学议题,其精准监测对区域可持续发展决策具有支撑作用。本研究以克里雅绿洲为研究对象,基于高分三号(GF-3)全极化合成孔径雷达数据与Landsat 8-OLI多光谱数据,结合野外实测土壤理化参数,构... 土地利用/覆被演变研究是解析人地关系的重要科学议题,其精准监测对区域可持续发展决策具有支撑作用。本研究以克里雅绿洲为研究对象,基于高分三号(GF-3)全极化合成孔径雷达数据与Landsat 8-OLI多光谱数据,结合野外实测土壤理化参数,构建多源遥感协同分类体系。将土壤盐渍化分级(轻度、中度、重度)作为土地覆被质量的核心量化指标,与土地利用类型(耕地、植被、水体、裸地)共同构成分类框架。通过应用八种极化分解方法、随机森林特征优选算法及U-Net深度学习模型,系统探讨干旱区绿洲土地利用/覆被分类的最优解译方案。实验结果表明,相较于传统影像分类算法,U-Net深度学习框架在分类精度指标上呈现显著优势,其总体分类精度提升至78.21%,Kappa系数达0.72.该模型有效融合雷达后向散射特征、光学光谱特征及土壤有机质含量等理化参数,通过多维特征空间构建解决植被-盐渍化混合像元的同谱异质问题。本研究提出的多源数据融合分类方法为绿洲生态系统监测提供了新的技术支撑,其分类结果的空间异质性解析能力为绿洲土地退化防治与资源管理决策提供了可靠的科学依据。 展开更多
关键词 积神经网络 GF-3 极化分解 克里雅绿洲 土地利用/覆被
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青钱柳复方调控MAPK/ERK和PI3K/AKT信号通路治疗糖尿病小鼠的药效与作用机制探讨
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作者 徐曼如 乔梦媛 +8 位作者 朱月 范依然 任攀 陈金鑫 钟芙蓉 陈明琪 李捷 张发荣 伍文彬 《世界科学技术-中医药现代化》 北大核心 2026年第1期164-177,共14页
目的探讨青钱柳复方对2型糖尿病(T2DM)小鼠血脂和血糖的改善作用及阐明其机制。方法通过网络药理学预测青钱柳复方改善T2DM的作用靶点;构建T2DM小鼠模型,将36只雄性昆明小鼠随机分为假手术空白组、模型组、二甲双胍阳性对照组以及青钱... 目的探讨青钱柳复方对2型糖尿病(T2DM)小鼠血脂和血糖的改善作用及阐明其机制。方法通过网络药理学预测青钱柳复方改善T2DM的作用靶点;构建T2DM小鼠模型,将36只雄性昆明小鼠随机分为假手术空白组、模型组、二甲双胍阳性对照组以及青钱柳复方低、中、高剂量组。在高脂喂养及链脲佐菌素注射诱导建立T2DM小鼠模型后进行灌胃给药,每日1次,连续28天。采用苏木素-伊红染色法观察小鼠胰腺病理变化;利用血糖仪监测空腹血糖、糖耐量;使用生化分析仪测定总胆固醇、甘油三酯水平;通过蛋白免疫印迹法检测小鼠胰腺中磷酸化及总量的信号蛋白表达,包括磷脂酰肌醇3-激酶(PI3K)、蛋白激酶B(AKT)、原癌基因酪氨酸蛋白激酶(SRC)和细胞外信号调节激酶(ERK)。结果网络药理学共筛选出青钱柳复方作用靶点365个,T2DM相关靶点2450个,其交集靶点287个,核心靶点主要包括信号转导及炎症相关蛋白,如SRC、STAT3(信号转导和转录激活因子3)、AKT1等。基因本体(GO)和京都基因与基因组百科全书(KEGG)分析表明,青钱柳复方主要调控信号转导、炎症反应和细胞凋亡等生物过程,涉及丝裂原活化蛋白激酶(MAPK)/ERK和PI3K/AKT信号通路。青钱柳复方显著改善T2DM小鼠胰腺病理损伤;降低空腹血糖、总胆固醇和甘油三酯水平,并抑制胰腺中PI3K、AKT、SRC和ERK的表达。结论网络药理学与动物实验验证表明青钱柳复方通过抑制MAPK/ERK和PI3K/AKT通路改善T2DM,未来将通过功能性阻断实验及多组学分析深入阐明其多靶点协同机制。 展开更多
关键词 青钱柳复方 2型糖尿病 网络药理学 MAPK/ERK信号通路 PI3K/AKT信号通路
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Biomimetic Gradient Lubrication Hydrogel Contrived by Self-Reinforced MOFs Nanoparticle Network
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作者 Desheng Liu Yixian Wang +8 位作者 Changcheng Bai Danli Hu Xingxing Yang Yaozhong Lu Tao Wu Fei Zhai Pan Jiang Xiaolong Wang Weimin Liu 《Nano-Micro Letters》 2026年第5期217-234,共18页
The development of gradient lubrication materials is critical for numerous biomedical applications,particularly in magnifying mechanical properties and service longevity.Herein,we present an innovative approach to fab... The development of gradient lubrication materials is critical for numerous biomedical applications,particularly in magnifying mechanical properties and service longevity.Herein,we present an innovative approach to fabricate biomimetic gradient lubrication hydrogel through the synergistic integration of three-dimensional(3D)printed metal-organic frameworks(MOFs)nanoparticle network hydrogel skeletons with bioinspired lubrication design.Specifically,robust hydrogel skeletons were engineered through single or multi-material 3D printing,followed by the in situ growth of MOFs nanoparticles within this hydrogel network to create a reinforced,load-bearing architecture.Subsequently,biomimetic lubrication capability was enabled by mechanically coupling another lubricating hydrogel within 3D-printed MOFs nanoparticle network hydrogel skeleton.The superficial layer is highly lubricious to ensure low coefficient of friction(~0.1141)and wear resistance(40,000 cycles),while the deeper layer is stiffer to afford the obligatory mechanical support(fracture strength~2.50 MPa).Furthermore,the gradient architecture stiffness of the hydrogel can be modulated by manipulating the spatial distribution of MOFs within the 3D-printed hydrogel skeleton.As a proof-of-concept,biomimetic gradient hydrogel meniscus structures with C-and O-shaped configurations were constructed by leveraging multi-material 3D printing,demonstrating exceptional lubrication performance.This innovative biomimetic design opens new avenues for creating implantable biomedical gradient lubricating materials with reinforced mechanical and lubrication performance. 展开更多
关键词 Biomimetic gradient architecture DIW 3D printing Lubricating hydrogel MOFs nanoparticle network Slippery meniscus
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Enhancing SS-OCT 3D image reconstruction:A real-time system with stripe artifact suppression and GPU parallel acceleration
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作者 Dandan LIU 《虚拟现实与智能硬件(中英文)》 2026年第1期115-130,共16页
Optical coherence tomography(OCT),particularly Swept-Source OCT,is widely employed in medical diagnostics and industrial inspections owing to its high-resolution imaging capabilities.However,Swept-Source OCT 3D imagin... Optical coherence tomography(OCT),particularly Swept-Source OCT,is widely employed in medical diagnostics and industrial inspections owing to its high-resolution imaging capabilities.However,Swept-Source OCT 3D imaging often suffers from stripe artifacts caused by unstable light sources,system noise,and environmental interference,posing challenges to real-time processing of large-scale datasets.To address this issue,this study introduces a real-time reconstruction system that integrates stripe-artifact suppression and parallel computing using a graphics processing unit.This approach employs a frequency-domain filtering algorithm with adaptive anti-suppression parameters,dynamically adjusted through an image quality evaluation function and optimized using a convolutional neural network for complex frequency-domain feature learning.Additionally,a graphics processing unit integrated 3D reconstruction framework is developed,enhancing data processing throughput and real-time performance via a dual-queue decoupling mechanism.Experimental results demonstrate significant improvements in structural similarity(0.92),peak signal-to-noise ratio(31.62 dB),and stripe suppression ratio(15.73 dB)compared with existing methods.On the RTX 4090 platform,the proposed system achieved an end-to-end delay of 94.36 milliseconds,a frame rate of 10.3 frames per second,and a throughput of 121.5 million voxels per second,effectively suppressing artifacts while preserving image details and enhancing real-time 3D reconstruction performance. 展开更多
关键词 Stripe artifact suppression 3D reconstruction GPU parallel computing Adaptive frequency domain filtering Convolutional neural network
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