As China's high-speed railway technology advances,high-speed trains have emerged as a pivotal mode of transportation,instrumental in facilitating passenger and freight mobility while fostering robust regional eco-...As China's high-speed railway technology advances,high-speed trains have emerged as a pivotal mode of transportation,instrumental in facilitating passenger and freight mobility while fostering robust regional eco-nomic and trade interactions.Nonetheless,the safety of train operations remains a paramount concern,prompting extensive research into the dynamic behavior of critical components,which is essential to ensuring seamless and secure transportation services.This article commences by comprehensively reviewing the current landscape and evolutionary trajectory of dynamic model analysis for both traditional bearings and axle box bearings.Emphasis is placed on elucidating the profound influence of diverse bearing fault types on the system's kinematic state,alongside delving into the research methodologies employed in developing multi-physics field coupling models.Subsequently,it expounds on the content of investigations focusing on various wheel and track impairments,grounded in the dynamic modeling of the bearing vehicle coupling system.Concurrently,the intricate interplay between wheel-rail excitation and axle box bearing faults on the system's performance is elucidated.Concludingly,the article underscores the inadequacy of current multi-source fault diagnosis meth-odologies in tackling the intricacies of complex train operating environments,thereby highlighting its sig-nificance as a pressing and vital research agenda for the future.展开更多
The spatial offset of bridge has a significant impact on the safety,comfort,and durability of high-speed railway(HSR)operations,so it is crucial to rapidly and effectively detect the spatial offset of operational HSR ...The spatial offset of bridge has a significant impact on the safety,comfort,and durability of high-speed railway(HSR)operations,so it is crucial to rapidly and effectively detect the spatial offset of operational HSR bridges.Drive-by monitoring of bridge uneven settlement demonstrates significant potential due to its practicality,cost-effectiveness,and efficiency.However,existing drive-by methods for detecting bridge offset have limitations such as reliance on a single data source,low detection accuracy,and the inability to identify lateral deformations of bridges.This paper proposes a novel drive-by inspection method for spatial offset of HSR bridge based on multi-source data fusion of comprehensive inspection train.Firstly,dung beetle optimizer-variational mode decomposition was employed to achieve adaptive decomposition of non-stationary dynamic signals,and explore the hidden temporal relationships in the data.Subsequently,a long short-term memory neural network was developed to achieve feature fusion of multi-source signal and accurate prediction of spatial settlement of HSR bridge.A dataset of track irregularities and CRH380A high-speed train responses was generated using a 3D train-track-bridge interaction model,and the accuracy and effectiveness of the proposed hybrid deep learning model were numerically validated.Finally,the reliability of the proposed drive-by inspection method was further validated by analyzing the actual measurement data obtained from comprehensive inspection train.The research findings indicate that the proposed approach enables rapid and accurate detection of spatial offset in HSR bridge,ensuring the long-term operational safety of HSR bridges.展开更多
Domain adaptation aims to reduce the distribution gap between the training data(source domain)and the target data.This enables effective predictions even for domains not seen during training.However,most conventional ...Domain adaptation aims to reduce the distribution gap between the training data(source domain)and the target data.This enables effective predictions even for domains not seen during training.However,most conventional domain adaptation methods assume a single source domain,making them less suitable for modern deep learning settings that rely on diverse and large-scale datasets.To address this limitation,recent research has focused on Multi-Source Domain Adaptation(MSDA),which aims to learn effectively from multiple source domains.In this paper,we propose Efficient Domain Transition for Multi-source(EDTM),a novel and efficient framework designed to tackle two major challenges in existing MSDA approaches:(1)integrating knowledge across different source domains and(2)aligning label distributions between source and target domains.EDTM leverages an ensemble-based classifier expert mechanism to enhance the contribution of source domains that are more similar to the target domain.To further stabilize the learning process and improve performance,we incorporate imitation learning into the training of the target model.In addition,Maximum Classifier Discrepancy(MCD)is employed to align class-wise label distributions between the source and target domains.Experiments were conducted using Digits-Five,one of the most representative benchmark datasets for MSDA.The results show that EDTM consistently outperforms existing methods in terms of average classification accuracy.Notably,EDTM achieved significantly higher performance on target domains such as Modified National Institute of Standards and Technolog with blended background images(MNIST-M)and Street View House Numbers(SVHN)datasets,demonstrating enhanced generalization compared to baseline approaches.Furthermore,an ablation study analyzing the contribution of each loss component validated the effectiveness of the framework,highlighting the importance of each module in achieving optimal performance.展开更多
While desalination is a key solution for global freshwater scarcity,its implementation faces environmental challenges due to concentrated brine byproducts mainly disposed of via coastal discharge systems.Solar interfa...While desalination is a key solution for global freshwater scarcity,its implementation faces environmental challenges due to concentrated brine byproducts mainly disposed of via coastal discharge systems.Solar interfacial evaporation offers sustainable management potential,yet inevitable salt nucleation at evaporation interfaces degrades photothermal conversion and operational stability via light scattering and pathway blockage.Inspired by the mangrove leaf,we propose a photothermal 3D polydopamine and polypyrrole polymerized spacer fabric(PPSF)-based upward hanging model evaporation configuration with a reverse water feeding mechanism.This design enables zero-liquiddischarge(ZLD)desalination through phase-separation crystallization.The interconnected porous architecture and the rough surface of the PPSF enable superior water transport,achieving excellent solar-absorbing efficiency of 97.8%.By adjusting the tilt angle(θ),the evaporator separates the evaporation and salt crystallization zones via controlled capillary-driven brine transport,minimizing heat dissipation from brine discharge.At an optimal tilt angle of 52°,the evaporator reaches an evaporation rate of 2.81 kg m^(−2) h^(−1) with minimal heat loss(0.366 W)under 1-sun illumination while treating a 7 wt%waste brine solution.Furthermore,it sustains an evaporation rate of 2.71 kg m^(−2) h^(−1) over 72 h while ensuring efficient salt recovery.These results highlight a scalable,energy-efficient approach for sustainable ZLD desalination.展开更多
Objective:To systematically summarize and evaluate the evidence on discharge preparation services for patients undergoing total knee arthroplasty,providing an evidence-based foundation for developing scientific and st...Objective:To systematically summarize and evaluate the evidence on discharge preparation services for patients undergoing total knee arthroplasty,providing an evidence-based foundation for developing scientific and standardized discharge preparation intervention programs in clinical practice.Methods:Following the“5S”evidence model,literature such as guidelines,expert consensuses,evidence summaries and randomized controlled trials related to discharge preparation services for total knee arthroplasty patients were retrieved from relevant websites and databases,both domestic and international,from database inception to August 31,2025.Two researchers independently screened the literature,conducted quality appraisals,and extracted and synthesized the evidence.Results:A total of 15 articles were included,comprising 3 guidelines,4 expert consensuses,3 evidence summaries,3 systematic reviews and 2 randomized controlled trials.Ultimately,23 pieces of evidence were summarized across five aspects.Conclusion:This study synthesizes the evidence on discharge preparation services for patients undergoing total knee arthroplasty.It is recommended that healthcare professionals apply this evidence in clinical practice,considering specific circumstances and patient needs.展开更多
Arc faults within the transformers can generate sudden pressure surges,constituting significant hazards that may precipitate oil tank explosions and severely compromise power system stability.Conventional power−freque...Arc faults within the transformers can generate sudden pressure surges,constituting significant hazards that may precipitate oil tank explosions and severely compromise power system stability.Conventional power−frequency arc discharge experiments encounter limitations in isolating pressure wave characteristics due to persistent gas generation and arc reignition.To circumvent these challenges,an oil-immersed impulse voltage discharge platform was conceived and engineered to investigate pressure wave propagation dynamics.A pressure numerical simulation model and theoretical model of oil−solid interface reflection and refraction were subsequently established to elucidate the pressure propagation mechanism.The experimental and simulation results show that the pressure wave generated by pulsed arc discharge in oil propagates radially in the form of spherical waves.Due to the viscous loss and wave front expansion of transformer oil,the peak pressure decays exponentially with distance,with a decay coefficientβ=1.15.When pressure waves encounter metal obstacles inside transformer oil,there are two propagation paths:direct transmission through and multiple reflections through,and a mode transformation of pressure waves occurs at the oil−solid interface,mainly propagating through obstacles in the form of transverse waves.This work quantitatively delineates the energy pressure wave coupling,propagation dynamics,and attenuation mechanisms,providing critical insights for assessing and mitigating arc fault-induced transformer explosion risks.展开更多
This study produced wide(900-1200 mm)AZ31 alloy sheets with varying thicknesses via continuous casting direct rolling(7 mm,6 mm)combined with stepwise warm rolling(4.5 mm,2 mm),examining the effects of this process on...This study produced wide(900-1200 mm)AZ31 alloy sheets with varying thicknesses via continuous casting direct rolling(7 mm,6 mm)combined with stepwise warm rolling(4.5 mm,2 mm),examining the effects of this process on microstructure,corrosion durability,mechanical properties,and discharge properties.Results showed that the reduced thickness significantly refined the grain size from 131.20µm to 7.90µm with the basal texture intensity reached 52%.Synergistic grain refinement,dislocation,and texture strengthening improved the yield strength(YS),ultimate tensile strength(UTS),and elongation(EL)of the 2 mm-thick sheet by 59.11%,39.75%,and 83.52%,respectively,compared to those of the 7 mm-thick sheet.Corrosion durability was also improved,with a corrosion rate of 2.19 mm·y^(-1)for the 2 mm sheet,which was 41%lower than that of the 7 mm sheet(3.72 mm·y^(-1)),due to the formation of a dense Al(OH)3 and layered double hydroxide corrosion film with mitigated micro-galvanic corrosion.As an Mg-air battery anode,the 2 mm sheet performed the best at 10 mA/cm^(2),achieving an anode efficiency of 61.18%,specific energy of 1660.50 mWh·g^(-1),easy discharge product detachment,and reduced self-corrosion.In summary,this study demonstrates a cost-effective and industrially viable approach that combines continuous casting direct rolling with stepwise warm rolling to produce ultra-wide AZ31 sheets with simultaneously improved overall properties,offering a novel strategy to expand the opportunity for commercial Mg alloys in both structural and functional applications.展开更多
Benthic habitat mapping is an emerging discipline in the international marine field in recent years,providing an effective tool for marine spatial planning,marine ecological management,and decision-making applications...Benthic habitat mapping is an emerging discipline in the international marine field in recent years,providing an effective tool for marine spatial planning,marine ecological management,and decision-making applications.Seabed sediment classification is one of the main contents of seabed habitat mapping.In response to the impact of remote sensing imaging quality and the limitations of acoustic measurement range,where a single data source does not fully reflect the substrate type,we proposed a high-precision seabed habitat sediment classification method that integrates data from multiple sources.Based on WorldView-2 multi-spectral remote sensing image data and multibeam bathymetry data,constructed a random forests(RF)classifier with optimal feature selection.A seabed sediment classification experiment integrating optical remote sensing and acoustic remote sensing data was carried out in the shallow water area of Wuzhizhou Island,Hainan,South China.Different seabed sediment types,such as sand,seagrass,and coral reefs were effectively identified,with an overall classification accuracy of 92%.Experimental results show that RF matrix optimized by fusing multi-source remote sensing data for feature selection were better than the classification results of simple combinations of data sources,which improved the accuracy of seabed sediment classification.Therefore,the method proposed in this paper can be effectively applied to high-precision seabed sediment classification and habitat mapping around islands and reefs.展开更多
Lacustrine groundwater discharge(LGD)plays an important role in water resources management.Previous studies have focused on LGD process in a single lake,but the differences in LGD process within the same region have n...Lacustrine groundwater discharge(LGD)plays an important role in water resources management.Previous studies have focused on LGD process in a single lake,but the differences in LGD process within the same region have not been thoroughly investigated.In this study,multiple tracers(hydrochemistry,𝛿D,𝛿18O and 222Rn)were used to compare mechanisms of LGD in Daihai and Ulansuhai Lake in Inner Mongoli1,Northwest China.The hydrochemical types showed a trend from groundwater to lake water,indicating a hydraulic connection between them.In addition,the𝛿D and𝛿18O values of sediment pore water were between the groundwater and lake water,indicating the LGD processes.The radon mass balance model was used to estimate the average groundwater discharge rates of Daihai and Ulansuhai Lake,which were 2.79 mm/day and 3.02 mm/day,respectively.The total nitrogen(TN),total phosphorus(TP),and fluoride inputs associated with LGD in Daihai Lake accounted for 97.52%,96.59%,and 95.84%of the total inputs,respectively.In contrast,TN,TP and fluoride inputs in Ulansuhai Lake were 53.56%,40.98%,and 36.25%,respectively.This indicates that the pollutant inputs associated with LGD posed a potential threat to the ecological stability of Daihai and Ulansuhai Lake.By comparison,the differences of LGD process and associated pollutant flux were controlled by hydrogeological conditions,lakebed permeability and human activities.This study provides a reference for water resources management in Daihai and Ulansuhai Lake basins while improving the understanding of LGD in the Yellow River basin.展开更多
This study exhibits a design of the discharge product film of a bulk AZ63-Ce-La-Ca(AZ63X)anode for Mg-air battery.An ideal discharge product film for Mg anode is that it could inhibit the anodic hydrogen evolution but...This study exhibits a design of the discharge product film of a bulk AZ63-Ce-La-Ca(AZ63X)anode for Mg-air battery.An ideal discharge product film for Mg anode is that it could inhibit the anodic hydrogen evolution but does not hinder the transfer of the electrons at the interface.Fortunately,the addition of Ce,La,and Ca into AZ63 alloy achieves this goal.The Mg-air battery with AZ63X anode in 3.5%Na Cl has an ultrahigh anodic efficiency of 85.7±1.7%and energy-density of 2431±53 mWh g^(-1)with the unique discharge product film,surpassing the values of most reported Mg-air batteries.Furthermore,the alloying elements reduce the anode delamination effect significantly by transforming the block Mg_(17)Al_(12)phase into the connected Mg_(17)Al_(12)structure and fine rod Al_(2)RE and Al_(2)Ca.展开更多
A novel precipitate-free Mg-0.1Sn anode with a homogeneous equal-axis grain structure was developed and rolled successfully at 573 K.Electrochemical test results indicate that the Mg-0.1Sn alloy exhibits enhanced anod...A novel precipitate-free Mg-0.1Sn anode with a homogeneous equal-axis grain structure was developed and rolled successfully at 573 K.Electrochemical test results indicate that the Mg-0.1Sn alloy exhibits enhanced anode dissolution kinetics.A Mg-air battery prepared using this anode exhibits a cell voltage of 1.626 V at 0.5 mA/cm^(2),reasonable anodic efficiency of 58.17%,and good specific energy of 1730.96 mW·h/g at 10 mA/cm^(2).This performance is attributed to the effective reactive anode surface,the suppressed chunk effect,and weak self-corrosion owing to the homogeneous basal texture.展开更多
Seawater desalination has been considered an important solution for water scarcity in coastal areas.Morocco,with its 3,500 km long coastline,has seen significant growth in population and industrial activities in recen...Seawater desalination has been considered an important solution for water scarcity in coastal areas.Morocco,with its 3,500 km long coastline,has seen significant growth in population and industrial activities in recent years.The dams that supply water to most regions of Morocco have faced periods of drought.This led the government to start a large-scale seawater desalination project that shall produce over 2 MM m^(3)/year.The most common environmental impact associated with desalination plants is the high concentration brine discharge which can alter the physical,chemical,and biological properties of the receiving water body,In fact,the increasing number of desalination plants along the coastline amplifies the potential risks that brine discharges pose to marine ecosystems.This highlights the critical need for regulations to manage pollutant concentrations in water,both at the discharge point(Effluent Standards-ES)and in the receiving environment(Ambient Standards-AS).Law 36-15,in its Article 72,grants any natural or legal person,whether public or private,the right to carry out seawater desalination to meet their own water needs or those of other users,in accordance with current legislation and regulations.However,the definition of regulations concerning marine environmental aspects and the substantial limits for discharges has not yet been specified.Indeed,these regulations will need to be developed with due consideration for the local biodiversity.These regulations should also take into account the technical criteria required to determine the compliance point and define the boundaries of the brine discharge impact zone.展开更多
To enhance the operational capacity and space utilization of baffle-drop shafts,this study improved the traditional baffle-drop shaft by expanding the wet-side space,incorporating large rotation-angle baffles,and inst...To enhance the operational capacity and space utilization of baffle-drop shafts,this study improved the traditional baffle-drop shaft by expanding the wet-side space,incorporating large rotation-angle baffles,and installing overflow holes in the dividing wall.A three-dimensional turbulent model was developed using ANSYS Fluent to simulate the hydraulic characteristics of both traditional and new baffle-drop shafts across various flow rates.The simulation results demonstrated that the new shaft design allowed for discharge from both the wet and dry sides,significantly improving operational capacity,with the dry side capable of handling 40%of the inlet flow.Compared to the traditional shaft,the new design reduced shaft wall pressures and decreased the mean and standard deviation of pressure on typical baffles by 21%and 63%,respectively,therefore enhancing structural safety.Additionally,the new shaft achieved a 2%-12%higher energy dissipation rate than the traditional shaft across different flow rates.This study offers valuable insights for the design and optimization of drop shafts in deep tunnel drainage systems.展开更多
The deposition layer on the discharge channel wall of a Hall thruster after long-term operation occasionally detaches from the wall and interferes with the plasma inside the channel,resulting in current pulse and thre...The deposition layer on the discharge channel wall of a Hall thruster after long-term operation occasionally detaches from the wall and interferes with the plasma inside the channel,resulting in current pulse and threatening the power supply.To understand the generation mechanism of the current pulse,the interaction between the peeling material and the channel plasma was studied by the particle-in-cell and Monte Carlo collision(PIC/MCC)method.The plasma evolution and distribution in the Hall thruster channel when peeling material existed were simulated.Simulation results show that the peeling material changes the electron transportation and ionization,and the effects are related to the position of the peeling material.When the peeling material invades the zone where the ionization rate is originally the highest without peeling material,the ionization process is almost terminated.The ionization suppression by the peeling material will cause the propellant gas to refill the channel exit.As the peeling material moves away,gas discharge is induced near the channel exit,resulting in anode current pulse.展开更多
Although lithium-ion batteries(LIBs)currently dominate a wide spectrum of energy storage applications,they face challenges such as fast cycle life decay and poor stability that hinder their further application.To addr...Although lithium-ion batteries(LIBs)currently dominate a wide spectrum of energy storage applications,they face challenges such as fast cycle life decay and poor stability that hinder their further application.To address these limitations,element doping has emerged as a prevalent strategy to enhance the discharge capacity and extend the durability of Li-Ni-Co-Mn(LNCM)ternary compounds.This study utilized a machine learning-driven feature screening method to effectively pinpoint four key features crucially impacting the initial discharge capacity(IC)of Li-Ni-Co-Mn(LNCM)ternary cathode materials.These features were also proved highly predictive for the 50^(th)cycle discharge capacity(EC).Additionally,the application of SHAP value analysis yielded an in-depth understanding of the interplay between these features and discharge performance.This insight offers valuable direction for future advancements in the development of LNCM cathode materials,effectively promoting this field toward greater efficiency and sustainability.展开更多
A macro-tidal tropical estuary with high fluvial discharge is characterized by both fragility and remarkable dynamism.This study utilizes the Salween River Delta(SRD)as a case example to examine the interplay between ...A macro-tidal tropical estuary with high fluvial discharge is characterized by both fragility and remarkable dynamism.This study utilizes the Salween River Delta(SRD)as a case example to examine the interplay between morphology and vegetation under similar tidal conditions.Our analysis of correlations and inferences revealed several significant trends in the SRD:(1)an overall expansion of land area and intertidal vegetation,with the most pronounced changes occurring in the eastern sector;(2)the predominance of river discharge influencing the southwestern and northern sectors,contrasted with the primary impact of storm surges in the eastern sector;and(3)three distinct causal relationships among estuarine morphology,vegetation,storm surges,and river discharge:a direct model where river discharge shapes estuarine morphology,a progressive model in which river discharge affects vegetation distribution,subsequently influencing estuarine morphology,and a hybrid model where storm surges directly impact vegetation and indirectly modify its distribution through changes in estuarine morphology.The stability of sediment supply and the role of intertidal vegetation are crucial for the continuous seaward advance,providing a vital foundation for the protection and development of estuarine deltas.展开更多
In this work,a series of experiments are carried out to investigate the effect of charge/discharge rates(1,2,3 and 4 C)and state of charges(SOCs,namely 0%,50%,75%and 100%)on thermal runaway(TR)and fire behavior of lit...In this work,a series of experiments are carried out to investigate the effect of charge/discharge rates(1,2,3 and 4 C)and state of charges(SOCs,namely 0%,50%,75%and 100%)on thermal runaway(TR)and fire behavior of lithium iron phosphate(LFP)batteries.The TR process caused by overheating LFP batteries is usually divided into four stages,with high temperatures and fire risks.High-rate charge and discharge damage the internal morphology and structural stability of materials seriously.The TR behavior of battery is fully aggravated,which is further manifested by the advanced opening of the safety vent,release of gas and occurrence of TR.With the increase of charging rate,the deteriorated TR characteristics can be discerned,such as the lower TR temperature,the shorter TR time,and the more serious TR consequences.Such changes can be assigned to the decline of battery stability.In addition,the battery SOC greatly impacts safety,especially the flame temperature and the severity of consequences.As for the 100%SOC battery cycled at 4 C,there is still a high risk of thermal runaway propagation at the position 1 m far away from the battery.This work helps to realize the TR and fire features of battery in-depth,enlightening the safety protection of battery.展开更多
Accurate estimation of understory terrain has significant scientific importance for maintaining ecosystem balance and biodiversity conservation.Addressing the issue of inadequate representation of spatial heterogeneit...Accurate estimation of understory terrain has significant scientific importance for maintaining ecosystem balance and biodiversity conservation.Addressing the issue of inadequate representation of spatial heterogeneity when traditional forest topographic inversion methods consider the entire forest as the inversion unit,this study pro⁃poses a differentiated modeling approach to forest types based on refined land cover classification.Taking Puerto Ri⁃co and Maryland as study areas,a multi-dimensional feature system is constructed by integrating multi-source re⁃mote sensing data:ICESat-2 spaceborne LiDAR is used to obtain benchmark values for understory terrain,topo⁃graphic factors such as slope and aspect are extracted based on SRTM data,and vegetation cover characteristics are analyzed using Landsat-8 multispectral imagery.This study incorporates forest type as a classification modeling con⁃dition and applies the random forest algorithm to build differentiated topographic inversion models.Experimental re⁃sults indicate that,compared to traditional whole-area modeling methods(RMSE=5.06 m),forest type-based classi⁃fication modeling significantly improves the accuracy of understory terrain estimation(RMSE=2.94 m),validating the effectiveness of spatial heterogeneity modeling.Further sensitivity analysis reveals that canopy structure parame⁃ters(with RMSE variation reaching 4.11 m)exert a stronger regulatory effect on estimation accuracy compared to forest cover,providing important theoretical support for optimizing remote sensing models of forest topography.展开更多
To explore the electrostatic discharge behavior of charged powders in industrial silos,discharge experiments are conducted based on a full-size industrial silo discharge platform.Electrostatic discharge mode,frequency...To explore the electrostatic discharge behavior of charged powders in industrial silos,discharge experiments are conducted based on a full-size industrial silo discharge platform.Electrostatic discharge mode,frequency,and energy are investigated for powders of different polarities.Although the powders have low charge-to-mass ratios(+0.087μC/kg for the positively charged powders and−0.26μC/kg for the negatively charged ones),electrostatic discharges occur approximately every 10 s,with the maximum discharge energy being 800 mJ.Powder polarity considerably influences discharge energy.The positive powders exhibit higher discharge energy than the negative ones,although discharge frequency remains similar for both.Effects of powder charge,humidity,and mass flow on discharge frequency and discharge energy are quantitatively analyzed,providing important insights for the improvement of safety in industrial powder handling.展开更多
Based on a homemade novel dielectric barrier discharge actuator with a rotating high-voltage electrode, this study investigates the influence of electrode rotating speed on the discharge characteristics, and the mecha...Based on a homemade novel dielectric barrier discharge actuator with a rotating high-voltage electrode, this study investigates the influence of electrode rotating speed on the discharge characteristics, and the mechanisms of discharge process under rotary conditions are discussed. The results demonstrate that when the high-voltage electrode is rotating,the distribution patterns of dielectric barrier discharge and the parameters of micro-discharge channels exhibit significant changes. Under a low rotating speed, the discharge patterns present as a series of separated discharge channels, resulting in uniform charge distribution but uneven electric field distribution in the gap. As the rotating speed increases, the electric field and the discharge channels will be affected by the rotation, so the electric field is more evenly distributed in the gap, and the discharge mode changes to a quasi-uniform discharge. With increasing distance from the rotation axis, the electric field strength gradually decreases, and the electric field force experienced by the micro-discharge channels during its formation weakens. Consequently, the average size of the micro-discharge channels increases, indicating that these channels are gradually stretched. The rotation of the electrode generates a significant number of accumulated charges, impacting the number of micro-discharge channels. The number of micro-discharge channels at the center of the electrode increases with rotating speed;however, due to channel stretching, the average size of the micro-discharge channels at the edge of the electrode also increases, leading to a decrease in their overall quantity. The research results reveal the significant impact of the electrode rotation on the characteristics of discharge channels, providing a theoretical basis for further optimal design of the rotating dielectric barrier discharge in various application.展开更多
基金Supported by the National Natural Science Foundation of China(Grant Nos.12393783,12302067,12172235,52072249)Joint Funds of the National Natural Science Foundation of China(Grant No.U24A2003)+3 种基金College Education Scientific Research Project of Hebei Province(Grant No.JZX2024006)Central Guiding Local Scientific and Technological Development Funding Project(Grant No.246Z2206G)the Key Research Project of China State Railway Group Co.,Ltd.(Grant No.N2024T009)S&T Program of Hebei(Grant No.21567622H).
文摘As China's high-speed railway technology advances,high-speed trains have emerged as a pivotal mode of transportation,instrumental in facilitating passenger and freight mobility while fostering robust regional eco-nomic and trade interactions.Nonetheless,the safety of train operations remains a paramount concern,prompting extensive research into the dynamic behavior of critical components,which is essential to ensuring seamless and secure transportation services.This article commences by comprehensively reviewing the current landscape and evolutionary trajectory of dynamic model analysis for both traditional bearings and axle box bearings.Emphasis is placed on elucidating the profound influence of diverse bearing fault types on the system's kinematic state,alongside delving into the research methodologies employed in developing multi-physics field coupling models.Subsequently,it expounds on the content of investigations focusing on various wheel and track impairments,grounded in the dynamic modeling of the bearing vehicle coupling system.Concurrently,the intricate interplay between wheel-rail excitation and axle box bearing faults on the system's performance is elucidated.Concludingly,the article underscores the inadequacy of current multi-source fault diagnosis meth-odologies in tackling the intricacies of complex train operating environments,thereby highlighting its sig-nificance as a pressing and vital research agenda for the future.
基金sponsored by the National Natural Science Foundation of China(Grant No.52178100).
文摘The spatial offset of bridge has a significant impact on the safety,comfort,and durability of high-speed railway(HSR)operations,so it is crucial to rapidly and effectively detect the spatial offset of operational HSR bridges.Drive-by monitoring of bridge uneven settlement demonstrates significant potential due to its practicality,cost-effectiveness,and efficiency.However,existing drive-by methods for detecting bridge offset have limitations such as reliance on a single data source,low detection accuracy,and the inability to identify lateral deformations of bridges.This paper proposes a novel drive-by inspection method for spatial offset of HSR bridge based on multi-source data fusion of comprehensive inspection train.Firstly,dung beetle optimizer-variational mode decomposition was employed to achieve adaptive decomposition of non-stationary dynamic signals,and explore the hidden temporal relationships in the data.Subsequently,a long short-term memory neural network was developed to achieve feature fusion of multi-source signal and accurate prediction of spatial settlement of HSR bridge.A dataset of track irregularities and CRH380A high-speed train responses was generated using a 3D train-track-bridge interaction model,and the accuracy and effectiveness of the proposed hybrid deep learning model were numerically validated.Finally,the reliability of the proposed drive-by inspection method was further validated by analyzing the actual measurement data obtained from comprehensive inspection train.The research findings indicate that the proposed approach enables rapid and accurate detection of spatial offset in HSR bridge,ensuring the long-term operational safety of HSR bridges.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.RS-2024-00406320)the Institute of Information&Communica-tions Technology Planning&Evaluation(IITP)-Innovative Human Resource Development for Local Intellectualization Program Grant funded by the Korea government(MSIT)(IITP-2026-RS-2023-00259678).
文摘Domain adaptation aims to reduce the distribution gap between the training data(source domain)and the target data.This enables effective predictions even for domains not seen during training.However,most conventional domain adaptation methods assume a single source domain,making them less suitable for modern deep learning settings that rely on diverse and large-scale datasets.To address this limitation,recent research has focused on Multi-Source Domain Adaptation(MSDA),which aims to learn effectively from multiple source domains.In this paper,we propose Efficient Domain Transition for Multi-source(EDTM),a novel and efficient framework designed to tackle two major challenges in existing MSDA approaches:(1)integrating knowledge across different source domains and(2)aligning label distributions between source and target domains.EDTM leverages an ensemble-based classifier expert mechanism to enhance the contribution of source domains that are more similar to the target domain.To further stabilize the learning process and improve performance,we incorporate imitation learning into the training of the target model.In addition,Maximum Classifier Discrepancy(MCD)is employed to align class-wise label distributions between the source and target domains.Experiments were conducted using Digits-Five,one of the most representative benchmark datasets for MSDA.The results show that EDTM consistently outperforms existing methods in terms of average classification accuracy.Notably,EDTM achieved significantly higher performance on target domains such as Modified National Institute of Standards and Technolog with blended background images(MNIST-M)and Street View House Numbers(SVHN)datasets,demonstrating enhanced generalization compared to baseline approaches.Furthermore,an ablation study analyzing the contribution of each loss component validated the effectiveness of the framework,highlighting the importance of each module in achieving optimal performance.
基金supported by National Key Research and Development Program of China(2022YFB3804902,2022YFB3804900)the National Natural Science Foundation of China(52203226,52161145406,42376045)the Fundamental Research Funds for the Central Universities(2232024Y-01,2232025D-02).
文摘While desalination is a key solution for global freshwater scarcity,its implementation faces environmental challenges due to concentrated brine byproducts mainly disposed of via coastal discharge systems.Solar interfacial evaporation offers sustainable management potential,yet inevitable salt nucleation at evaporation interfaces degrades photothermal conversion and operational stability via light scattering and pathway blockage.Inspired by the mangrove leaf,we propose a photothermal 3D polydopamine and polypyrrole polymerized spacer fabric(PPSF)-based upward hanging model evaporation configuration with a reverse water feeding mechanism.This design enables zero-liquiddischarge(ZLD)desalination through phase-separation crystallization.The interconnected porous architecture and the rough surface of the PPSF enable superior water transport,achieving excellent solar-absorbing efficiency of 97.8%.By adjusting the tilt angle(θ),the evaporator separates the evaporation and salt crystallization zones via controlled capillary-driven brine transport,minimizing heat dissipation from brine discharge.At an optimal tilt angle of 52°,the evaporator reaches an evaporation rate of 2.81 kg m^(−2) h^(−1) with minimal heat loss(0.366 W)under 1-sun illumination while treating a 7 wt%waste brine solution.Furthermore,it sustains an evaporation rate of 2.71 kg m^(−2) h^(−1) over 72 h while ensuring efficient salt recovery.These results highlight a scalable,energy-efficient approach for sustainable ZLD desalination.
文摘Objective:To systematically summarize and evaluate the evidence on discharge preparation services for patients undergoing total knee arthroplasty,providing an evidence-based foundation for developing scientific and standardized discharge preparation intervention programs in clinical practice.Methods:Following the“5S”evidence model,literature such as guidelines,expert consensuses,evidence summaries and randomized controlled trials related to discharge preparation services for total knee arthroplasty patients were retrieved from relevant websites and databases,both domestic and international,from database inception to August 31,2025.Two researchers independently screened the literature,conducted quality appraisals,and extracted and synthesized the evidence.Results:A total of 15 articles were included,comprising 3 guidelines,4 expert consensuses,3 evidence summaries,3 systematic reviews and 2 randomized controlled trials.Ultimately,23 pieces of evidence were summarized across five aspects.Conclusion:This study synthesizes the evidence on discharge preparation services for patients undergoing total knee arthroplasty.It is recommended that healthcare professionals apply this evidence in clinical practice,considering specific circumstances and patient needs.
基金funded by the Science and Technology Program of State Grid Corporation of China(5500-202356358A-2-1-ZX).
文摘Arc faults within the transformers can generate sudden pressure surges,constituting significant hazards that may precipitate oil tank explosions and severely compromise power system stability.Conventional power−frequency arc discharge experiments encounter limitations in isolating pressure wave characteristics due to persistent gas generation and arc reignition.To circumvent these challenges,an oil-immersed impulse voltage discharge platform was conceived and engineered to investigate pressure wave propagation dynamics.A pressure numerical simulation model and theoretical model of oil−solid interface reflection and refraction were subsequently established to elucidate the pressure propagation mechanism.The experimental and simulation results show that the pressure wave generated by pulsed arc discharge in oil propagates radially in the form of spherical waves.Due to the viscous loss and wave front expansion of transformer oil,the peak pressure decays exponentially with distance,with a decay coefficientβ=1.15.When pressure waves encounter metal obstacles inside transformer oil,there are two propagation paths:direct transmission through and multiple reflections through,and a mode transformation of pressure waves occurs at the oil−solid interface,mainly propagating through obstacles in the form of transverse waves.This work quantitatively delineates the energy pressure wave coupling,propagation dynamics,and attenuation mechanisms,providing critical insights for assessing and mitigating arc fault-induced transformer explosion risks.
基金funded by the National Natural Science Foundation of China(No.52204407,No.22208220,No.52304408,No.52304398)the Zhejiang Provincial Natural Science Foundation of China(No.LQN25E010012)the Key Industrial Technology Research and Basic public welfare program projects in Shaoxing city(2023B41003,2023A11004 and 2023A11005).
文摘This study produced wide(900-1200 mm)AZ31 alloy sheets with varying thicknesses via continuous casting direct rolling(7 mm,6 mm)combined with stepwise warm rolling(4.5 mm,2 mm),examining the effects of this process on microstructure,corrosion durability,mechanical properties,and discharge properties.Results showed that the reduced thickness significantly refined the grain size from 131.20µm to 7.90µm with the basal texture intensity reached 52%.Synergistic grain refinement,dislocation,and texture strengthening improved the yield strength(YS),ultimate tensile strength(UTS),and elongation(EL)of the 2 mm-thick sheet by 59.11%,39.75%,and 83.52%,respectively,compared to those of the 7 mm-thick sheet.Corrosion durability was also improved,with a corrosion rate of 2.19 mm·y^(-1)for the 2 mm sheet,which was 41%lower than that of the 7 mm sheet(3.72 mm·y^(-1)),due to the formation of a dense Al(OH)3 and layered double hydroxide corrosion film with mitigated micro-galvanic corrosion.As an Mg-air battery anode,the 2 mm sheet performed the best at 10 mA/cm^(2),achieving an anode efficiency of 61.18%,specific energy of 1660.50 mWh·g^(-1),easy discharge product detachment,and reduced self-corrosion.In summary,this study demonstrates a cost-effective and industrially viable approach that combines continuous casting direct rolling with stepwise warm rolling to produce ultra-wide AZ31 sheets with simultaneously improved overall properties,offering a novel strategy to expand the opportunity for commercial Mg alloys in both structural and functional applications.
基金Supported by the National Natural Science Foundation of China(Nos.42376185,41876111)the Shandong Provincial Natural Science Foundation(No.ZR2023MD073)。
文摘Benthic habitat mapping is an emerging discipline in the international marine field in recent years,providing an effective tool for marine spatial planning,marine ecological management,and decision-making applications.Seabed sediment classification is one of the main contents of seabed habitat mapping.In response to the impact of remote sensing imaging quality and the limitations of acoustic measurement range,where a single data source does not fully reflect the substrate type,we proposed a high-precision seabed habitat sediment classification method that integrates data from multiple sources.Based on WorldView-2 multi-spectral remote sensing image data and multibeam bathymetry data,constructed a random forests(RF)classifier with optimal feature selection.A seabed sediment classification experiment integrating optical remote sensing and acoustic remote sensing data was carried out in the shallow water area of Wuzhizhou Island,Hainan,South China.Different seabed sediment types,such as sand,seagrass,and coral reefs were effectively identified,with an overall classification accuracy of 92%.Experimental results show that RF matrix optimized by fusing multi-source remote sensing data for feature selection were better than the classification results of simple combinations of data sources,which improved the accuracy of seabed sediment classification.Therefore,the method proposed in this paper can be effectively applied to high-precision seabed sediment classification and habitat mapping around islands and reefs.
基金supported by the Natural Science Foundation of Inner Mongolia Autonomous Region of China(No.2023QN04011)the National Natural Science Foundation of China(Nos.42307092 and 52279067)+1 种基金Ordos Science and Technology Major Project(No.ZD20232303)Project of Key Laboratory of River and Lake in Inner Mongolia Autonomous Region(No.2022QZBZ0003).
文摘Lacustrine groundwater discharge(LGD)plays an important role in water resources management.Previous studies have focused on LGD process in a single lake,but the differences in LGD process within the same region have not been thoroughly investigated.In this study,multiple tracers(hydrochemistry,𝛿D,𝛿18O and 222Rn)were used to compare mechanisms of LGD in Daihai and Ulansuhai Lake in Inner Mongoli1,Northwest China.The hydrochemical types showed a trend from groundwater to lake water,indicating a hydraulic connection between them.In addition,the𝛿D and𝛿18O values of sediment pore water were between the groundwater and lake water,indicating the LGD processes.The radon mass balance model was used to estimate the average groundwater discharge rates of Daihai and Ulansuhai Lake,which were 2.79 mm/day and 3.02 mm/day,respectively.The total nitrogen(TN),total phosphorus(TP),and fluoride inputs associated with LGD in Daihai Lake accounted for 97.52%,96.59%,and 95.84%of the total inputs,respectively.In contrast,TN,TP and fluoride inputs in Ulansuhai Lake were 53.56%,40.98%,and 36.25%,respectively.This indicates that the pollutant inputs associated with LGD posed a potential threat to the ecological stability of Daihai and Ulansuhai Lake.By comparison,the differences of LGD process and associated pollutant flux were controlled by hydrogeological conditions,lakebed permeability and human activities.This study provides a reference for water resources management in Daihai and Ulansuhai Lake basins while improving the understanding of LGD in the Yellow River basin.
基金supported by the National Natural Science Foundation of China(52471095)National Key Research and Development Program of China(Grant No.2023YFC2811404)Natural Science Foundation of Xiamen,China(No.3502Z20227015)。
文摘This study exhibits a design of the discharge product film of a bulk AZ63-Ce-La-Ca(AZ63X)anode for Mg-air battery.An ideal discharge product film for Mg anode is that it could inhibit the anodic hydrogen evolution but does not hinder the transfer of the electrons at the interface.Fortunately,the addition of Ce,La,and Ca into AZ63 alloy achieves this goal.The Mg-air battery with AZ63X anode in 3.5%Na Cl has an ultrahigh anodic efficiency of 85.7±1.7%and energy-density of 2431±53 mWh g^(-1)with the unique discharge product film,surpassing the values of most reported Mg-air batteries.Furthermore,the alloying elements reduce the anode delamination effect significantly by transforming the block Mg_(17)Al_(12)phase into the connected Mg_(17)Al_(12)structure and fine rod Al_(2)RE and Al_(2)Ca.
基金partially supported by the National Natural Science Foundation of China(No.51901153)Shanxi Scholarship Council of China(No.2019032)+1 种基金the Natural Science Foundation of Shanxi,China(No.202103021224049)the Shanxi Zhejiang University New Materials and Chemical Research Institute Scientific Research Project,China(No.2022SX-TD025)。
文摘A novel precipitate-free Mg-0.1Sn anode with a homogeneous equal-axis grain structure was developed and rolled successfully at 573 K.Electrochemical test results indicate that the Mg-0.1Sn alloy exhibits enhanced anode dissolution kinetics.A Mg-air battery prepared using this anode exhibits a cell voltage of 1.626 V at 0.5 mA/cm^(2),reasonable anodic efficiency of 58.17%,and good specific energy of 1730.96 mW·h/g at 10 mA/cm^(2).This performance is attributed to the effective reactive anode surface,the suppressed chunk effect,and weak self-corrosion owing to the homogeneous basal texture.
文摘Seawater desalination has been considered an important solution for water scarcity in coastal areas.Morocco,with its 3,500 km long coastline,has seen significant growth in population and industrial activities in recent years.The dams that supply water to most regions of Morocco have faced periods of drought.This led the government to start a large-scale seawater desalination project that shall produce over 2 MM m^(3)/year.The most common environmental impact associated with desalination plants is the high concentration brine discharge which can alter the physical,chemical,and biological properties of the receiving water body,In fact,the increasing number of desalination plants along the coastline amplifies the potential risks that brine discharges pose to marine ecosystems.This highlights the critical need for regulations to manage pollutant concentrations in water,both at the discharge point(Effluent Standards-ES)and in the receiving environment(Ambient Standards-AS).Law 36-15,in its Article 72,grants any natural or legal person,whether public or private,the right to carry out seawater desalination to meet their own water needs or those of other users,in accordance with current legislation and regulations.However,the definition of regulations concerning marine environmental aspects and the substantial limits for discharges has not yet been specified.Indeed,these regulations will need to be developed with due consideration for the local biodiversity.These regulations should also take into account the technical criteria required to determine the compliance point and define the boundaries of the brine discharge impact zone.
基金supported by the National Key Research and Development Program of China(Grant No.2021YFD1700802).
文摘To enhance the operational capacity and space utilization of baffle-drop shafts,this study improved the traditional baffle-drop shaft by expanding the wet-side space,incorporating large rotation-angle baffles,and installing overflow holes in the dividing wall.A three-dimensional turbulent model was developed using ANSYS Fluent to simulate the hydraulic characteristics of both traditional and new baffle-drop shafts across various flow rates.The simulation results demonstrated that the new shaft design allowed for discharge from both the wet and dry sides,significantly improving operational capacity,with the dry side capable of handling 40%of the inlet flow.Compared to the traditional shaft,the new design reduced shaft wall pressures and decreased the mean and standard deviation of pressure on typical baffles by 21%and 63%,respectively,therefore enhancing structural safety.Additionally,the new shaft achieved a 2%-12%higher energy dissipation rate than the traditional shaft across different flow rates.This study offers valuable insights for the design and optimization of drop shafts in deep tunnel drainage systems.
基金supported by National Natural Science Foundation of China(No.U23B20152).
文摘The deposition layer on the discharge channel wall of a Hall thruster after long-term operation occasionally detaches from the wall and interferes with the plasma inside the channel,resulting in current pulse and threatening the power supply.To understand the generation mechanism of the current pulse,the interaction between the peeling material and the channel plasma was studied by the particle-in-cell and Monte Carlo collision(PIC/MCC)method.The plasma evolution and distribution in the Hall thruster channel when peeling material existed were simulated.Simulation results show that the peeling material changes the electron transportation and ionization,and the effects are related to the position of the peeling material.When the peeling material invades the zone where the ionization rate is originally the highest without peeling material,the ionization process is almost terminated.The ionization suppression by the peeling material will cause the propellant gas to refill the channel exit.As the peeling material moves away,gas discharge is induced near the channel exit,resulting in anode current pulse.
基金supported by the National Natural Science Foundation of China(Nos.52122408,52071023)the Program for Science&Technology Innovation Talents in the University of Henan Province(No.22HASTIT1006)+2 种基金the Program for Central Plains Talents(No.ZYYCYU202012172)the Ministry of Education,Singapore(No.RG70/20)the Opening Project of National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials,Henan University of Science and Technology(No.HKDNM201906).
文摘Although lithium-ion batteries(LIBs)currently dominate a wide spectrum of energy storage applications,they face challenges such as fast cycle life decay and poor stability that hinder their further application.To address these limitations,element doping has emerged as a prevalent strategy to enhance the discharge capacity and extend the durability of Li-Ni-Co-Mn(LNCM)ternary compounds.This study utilized a machine learning-driven feature screening method to effectively pinpoint four key features crucially impacting the initial discharge capacity(IC)of Li-Ni-Co-Mn(LNCM)ternary cathode materials.These features were also proved highly predictive for the 50^(th)cycle discharge capacity(EC).Additionally,the application of SHAP value analysis yielded an in-depth understanding of the interplay between these features and discharge performance.This insight offers valuable direction for future advancements in the development of LNCM cathode materials,effectively promoting this field toward greater efficiency and sustainability.
基金National Natural Science Foundation of China,No.41906148,No.42271086Rejuvenating Yunnan Talents Support Plan Young Talent Program,No.XDYC-QNRC-2023-0322。
文摘A macro-tidal tropical estuary with high fluvial discharge is characterized by both fragility and remarkable dynamism.This study utilizes the Salween River Delta(SRD)as a case example to examine the interplay between morphology and vegetation under similar tidal conditions.Our analysis of correlations and inferences revealed several significant trends in the SRD:(1)an overall expansion of land area and intertidal vegetation,with the most pronounced changes occurring in the eastern sector;(2)the predominance of river discharge influencing the southwestern and northern sectors,contrasted with the primary impact of storm surges in the eastern sector;and(3)three distinct causal relationships among estuarine morphology,vegetation,storm surges,and river discharge:a direct model where river discharge shapes estuarine morphology,a progressive model in which river discharge affects vegetation distribution,subsequently influencing estuarine morphology,and a hybrid model where storm surges directly impact vegetation and indirectly modify its distribution through changes in estuarine morphology.The stability of sediment supply and the role of intertidal vegetation are crucial for the continuous seaward advance,providing a vital foundation for the protection and development of estuarine deltas.
基金supported by the National Key Research and Development Plan(2023YFC3009900)the National Natural Science Foundation of China(52104197,52272396,52474233)+3 种基金Hongkong Scholar Program(XJ2022022)Research Grants Council of the Hong Kong Special Administrative Region(City U11214221)Natural Science Foundation of the Jiangsu Higher Education Institutions(21KJB620001)the Open Fund of the State Key Laboratory of Fire Science(SKLFS)Program(HZ2022-KF04)。
文摘In this work,a series of experiments are carried out to investigate the effect of charge/discharge rates(1,2,3 and 4 C)and state of charges(SOCs,namely 0%,50%,75%and 100%)on thermal runaway(TR)and fire behavior of lithium iron phosphate(LFP)batteries.The TR process caused by overheating LFP batteries is usually divided into four stages,with high temperatures and fire risks.High-rate charge and discharge damage the internal morphology and structural stability of materials seriously.The TR behavior of battery is fully aggravated,which is further manifested by the advanced opening of the safety vent,release of gas and occurrence of TR.With the increase of charging rate,the deteriorated TR characteristics can be discerned,such as the lower TR temperature,the shorter TR time,and the more serious TR consequences.Such changes can be assigned to the decline of battery stability.In addition,the battery SOC greatly impacts safety,especially the flame temperature and the severity of consequences.As for the 100%SOC battery cycled at 4 C,there is still a high risk of thermal runaway propagation at the position 1 m far away from the battery.This work helps to realize the TR and fire features of battery in-depth,enlightening the safety protection of battery.
基金Supported by the National Natural Science Foundation of China(42401488,42071351)the National Key Research and Development Program of China(2020YFA0608501,2017YFB0504204)+4 种基金the Liaoning Revitalization Talents Program(XLYC1802027)the Talent Recruited Program of the Chinese Academy of Science(Y938091)the Project Supported Discipline Innovation Team of the Liaoning Technical University(LNTU20TD-23)the Liaoning Province Doctoral Research Initiation Fund Program(2023-BS-202)the Basic Research Projects of Liaoning Department of Education(JYTQN2023202)。
文摘Accurate estimation of understory terrain has significant scientific importance for maintaining ecosystem balance and biodiversity conservation.Addressing the issue of inadequate representation of spatial heterogeneity when traditional forest topographic inversion methods consider the entire forest as the inversion unit,this study pro⁃poses a differentiated modeling approach to forest types based on refined land cover classification.Taking Puerto Ri⁃co and Maryland as study areas,a multi-dimensional feature system is constructed by integrating multi-source re⁃mote sensing data:ICESat-2 spaceborne LiDAR is used to obtain benchmark values for understory terrain,topo⁃graphic factors such as slope and aspect are extracted based on SRTM data,and vegetation cover characteristics are analyzed using Landsat-8 multispectral imagery.This study incorporates forest type as a classification modeling con⁃dition and applies the random forest algorithm to build differentiated topographic inversion models.Experimental re⁃sults indicate that,compared to traditional whole-area modeling methods(RMSE=5.06 m),forest type-based classi⁃fication modeling significantly improves the accuracy of understory terrain estimation(RMSE=2.94 m),validating the effectiveness of spatial heterogeneity modeling.Further sensitivity analysis reveals that canopy structure parame⁃ters(with RMSE variation reaching 4.11 m)exert a stronger regulatory effect on estimation accuracy compared to forest cover,providing important theoretical support for optimizing remote sensing models of forest topography.
基金The National Natural Science Foundation of China(No.51976039)。
文摘To explore the electrostatic discharge behavior of charged powders in industrial silos,discharge experiments are conducted based on a full-size industrial silo discharge platform.Electrostatic discharge mode,frequency,and energy are investigated for powders of different polarities.Although the powders have low charge-to-mass ratios(+0.087μC/kg for the positively charged powders and−0.26μC/kg for the negatively charged ones),electrostatic discharges occur approximately every 10 s,with the maximum discharge energy being 800 mJ.Powder polarity considerably influences discharge energy.The positive powders exhibit higher discharge energy than the negative ones,although discharge frequency remains similar for both.Effects of powder charge,humidity,and mass flow on discharge frequency and discharge energy are quantitatively analyzed,providing important insights for the improvement of safety in industrial powder handling.
基金Project supported by the National Natural Science Foundation of China (Grant No. 52377135)。
文摘Based on a homemade novel dielectric barrier discharge actuator with a rotating high-voltage electrode, this study investigates the influence of electrode rotating speed on the discharge characteristics, and the mechanisms of discharge process under rotary conditions are discussed. The results demonstrate that when the high-voltage electrode is rotating,the distribution patterns of dielectric barrier discharge and the parameters of micro-discharge channels exhibit significant changes. Under a low rotating speed, the discharge patterns present as a series of separated discharge channels, resulting in uniform charge distribution but uneven electric field distribution in the gap. As the rotating speed increases, the electric field and the discharge channels will be affected by the rotation, so the electric field is more evenly distributed in the gap, and the discharge mode changes to a quasi-uniform discharge. With increasing distance from the rotation axis, the electric field strength gradually decreases, and the electric field force experienced by the micro-discharge channels during its formation weakens. Consequently, the average size of the micro-discharge channels increases, indicating that these channels are gradually stretched. The rotation of the electrode generates a significant number of accumulated charges, impacting the number of micro-discharge channels. The number of micro-discharge channels at the center of the electrode increases with rotating speed;however, due to channel stretching, the average size of the micro-discharge channels at the edge of the electrode also increases, leading to a decrease in their overall quantity. The research results reveal the significant impact of the electrode rotation on the characteristics of discharge channels, providing a theoretical basis for further optimal design of the rotating dielectric barrier discharge in various application.
