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
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 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
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
Flexible surface micro-discharge plasma is a non-thermal plasma technique used for treating wounds in a painless way, with significant efficacy for chronic or hard-to-heal wounds. In this study, a confined space was d...Flexible surface micro-discharge plasma is a non-thermal plasma technique used for treating wounds in a painless way, with significant efficacy for chronic or hard-to-heal wounds. In this study, a confined space was designed to simulate wound conditions, with gelatin used to simulate wound tissue. The distinction between open and confined spaces was explored, and the effects of temperature, humidity, discharge power and the gap size within the confined space on the plasma characteristics were analyzed. It was found that temperature, humidity and discharge power are important factors that affect the concentration distribution of active components and the mode transition between ozone and nitrogen oxides. Compared to open space, the concentration of ozone in confined space was relatively lower, which facilitated the formation of nitrogen oxides. In open space, the discharge was dominated by ozone initially. As the temperature,humidity and discharge power increased, nitrogen oxides in the gas-phase products were gradually detected. In confined space, nitrogen oxides can be detected at an early stage and at much higher concentrations than ozone concentration. Furthermore, as the gap of the confined space decreased, the concentration of ozone was observed to decrease while that of nitrate increased, and the rate of this concentration change was further accelerated at higher temperature and higher power. It was shown that ozone concentration decreased from 0.11 to 0.03 μmol and the nitrate concentration increased from 20.5 to 24.5 μmol when the spacing in the confined space was reduced from 5 to 1 mm, the temperature of the external discharge was controlled at 40 ℃, and the discharge power was 12 W. In summary, this study reveals the formation and transformation mechanisms of active substances in air surface micro-discharge plasma within confined space, providing foundational data for its medical applications.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
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
Objective:To investigate the application effect of the discharge preparation plan based on the ADOPT nursing model in patients with first-visit ischemic stroke.Methods:Eighty patients with first-visit ischemic stroke ...Objective:To investigate the application effect of the discharge preparation plan based on the ADOPT nursing model in patients with first-visit ischemic stroke.Methods:Eighty patients with first-visit ischemic stroke admitted to our hospital from June 1,2024 to November 31,2024 were selected and divided into a control group(June 1,2024 to August 30,2024)and an intervention group(September 1,2024 to November 31,2024)according to different admission times,with 40 cases in each group.The control group received routine care and discharge guidance,while the intervention group received a discharge preparation plan based on the ADOPT model on the basis of routine care.The discharge readiness[Discharge Readiness Scale(RHDS)]of patients on the day of discharge was compared.Self-efficacy at 3 months after discharge[evaluated using the Chronic Disease Self-Efficacy Scale(SECD6)],activities of daily living[evaluated using the Barthel index(BI)],blood glucose and blood pressure indicators(diastolic blood pressure,systolic blood pressure,FPG,2 h PG),and readmission rate within 3 months after discharge were also compared between the two groups.Results:On the day of discharge,the RHDS-related dimension scores of the intervention group were higher than those of the control group(t=17.993,8.560,10.243,p<0.05);Three months after discharge,the SECD6 score and BI score of the intervention group were higher than those of the control group(t=8.910,10.899,both p<0.05);Systolic blood pressure,diastolic blood pressure,FPG and 2h PG in the intervention group were lower than those in the control group(t=8.868,4.794,3.829,7.121,all p<0.05);Within 3 months after discharge,the readmission rate of the intervention group was lower than that of the control group(χ^(2)=5.165,2 p<0.05).Conclusion:The discharge preparation plan based on the ADOPT nursing model,when applied to patients with first-visit ischemic stroke,can not only enhance self-efficacy and discharge preparation,improve activities of daily living,but also optimize blood glucose and blood pressure indicators and reduce the readmission rate,which is worthy of reference.展开更多
Research has been carried out on a hybrid discharge ion thruster,aiming to combine the advantages of Direct Current(DC)discharge ion thrusters(known for their high thrust density and high power supply efficiency)with ...Research has been carried out on a hybrid discharge ion thruster,aiming to combine the advantages of Direct Current(DC)discharge ion thrusters(known for their high thrust density and high power supply efficiency)with microwave discharge ion thrusters(which do not require a hollow cathode and are capable of efficient ionization at low pressures).Comparative experiments with different anode structures and single-probe diagnostics revealed that applying a DC bias voltage created a new ionization zone based on microwave discharge.This DC bias increased the sheath potential of the screen grid and led to an elevation in electron temperature and plasma density.It is speculated that the reduced loss of high-energy electrons generated by microwave discharge at the screen grid is the primary reason for the enhanced discharge.By adding a DC bias of approximately 50 V to the microwave discharge,the screen grid current was doubled without a significant increase in discharge power consumption.Under appropriate bias voltages that consider minimizing ion sputtering,DC bias holds promise as a design approach to increase the extracted beam current in microwave ion thrusters.展开更多
As a popular approach to producing atmospheric pressure non-thermal plasma,dielectric barrier discharge(DBD)has been extensively used in various application fields.In this paper,DBD with wavy dielectric layers is nume...As a popular approach to producing atmospheric pressure non-thermal plasma,dielectric barrier discharge(DBD)has been extensively used in various application fields.In this paper,DBD with wavy dielectric layers is numerically simulated in atmospheric pressure helium mixed with trace nitrogen based on a fluid model.With varying relative position(phase difference(Δφ))of the wavy surfaces,there is a positive discharge and a negative discharge per voltage cycle,each of which consists of a pulse stage and a hump stage.For the pulse stage,maximal current increases with increasingΔφ.Results show that DBD with the wavy surfaces appears as discrete micro-discharges(MDs),which are self-organized to different patterns with varyingΔφ.The MDs are vertical and uniformly-spaced withΔφ=0,which are self-organized in pairs withΔφ=π/4.These MD pairs are merged into some bright wide MDs withΔφ=π/2.In addition,narrow MDs appear between tilted wide MDs withΔφ=3π/4.WithΔφ=π,the pattern is composed of wide and narrow MDs,which are vertical and appear alternately.To elucidate the formation mechanism of the patterns with differentΔφ,temporal evolutions of electron density and electric field are investigated for the positive discharge.Moreover,surface charge on the wavy dielectric layers has also been compared with differentΔφ.展开更多
This paper describes the realization of a homogeneous dielectric barrier discharge(DBD)in argon at atmospheric pressure.The effect of the morphology of the dielectric surface(especially the dielectric surface covered ...This paper describes the realization of a homogeneous dielectric barrier discharge(DBD)in argon at atmospheric pressure.The effect of the morphology of the dielectric surface(especially the dielectric surface covered by hollow ceramic beads(99%Al_(2)O_(3))with different diameters)on discharge is investigated.With different dielectrics,the argon DBD presents two discharge modes:a filamentary mode and a homogeneous mode.Fast photography shows that the filamentary mode operates in a streamer discharge,and the homogeneous mode operates in a Townsend discharge regime.It is found that a homogeneous discharge can be generated within a certain voltage range.The voltage amplitude range decreases,and the breakdown voltage increases with the increase in the mean diameter of the ceramic beads.Waveforms of the total current and optical emission signal present stochastic pulses per half voltage cycle for the filamentary mode,whereas there is one single hump per half voltage cycle for the homogeneous mode.In the homogeneous mode,the intensity of the optical emission decreases with the mean diameter of the ceramic beads.The optical emission spectrum is mainly composed of atomic lines of argon and the second positive system of molecular nitrogen.It reveals that the electron density decreases with the increasing mean diameter of the ceramic beads.The vibrational temperature increases with the increasing mean diameter of the ceramic beads.It is believed that a large number of microdischarges are formed,and smaller ceramic beads have a larger activation surface area and more point discharge.Electrons liberated in the shallow well and electrons generated from microdischarges can increase the secondary electron emission coefficient of the cathode and provide initial electrons for discharge continuously.Therefore,the breakdown electric field is reduced,which contributes to easier generation of homogeneous discharge.This is confirmed by the simulation results.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
With the swift development of economy, the water quality of Beijing is becoming worse day by day and hampers the sustainable development obviously. In this paper, the current conditions of the municipal wastewater str...With the swift development of economy, the water quality of Beijing is becoming worse day by day and hampers the sustainable development obviously. In this paper, the current conditions of the municipal wastewater structure in the industrial sectors are analysed and discussed in terms of the indicators, such as direct wastewater\|discharge coefficient, complete wastewater\|discharge coefficient, direct discharge coefficient of COD and complete discharge coefficient of COD, by taking a year of 1990s as the base year. Some countermeasures are studied and the corresponding recommendations are put forward in order to improve the water environment in Beijing. This provides a scientific ground for coordinating the relationship between the aquatic environment and economic growth in this city.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
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
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
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.
基金supported by Postgraduate Research&Practice Innovation Program of Jiangsu Province (No. 1003016001)。
文摘Flexible surface micro-discharge plasma is a non-thermal plasma technique used for treating wounds in a painless way, with significant efficacy for chronic or hard-to-heal wounds. In this study, a confined space was designed to simulate wound conditions, with gelatin used to simulate wound tissue. The distinction between open and confined spaces was explored, and the effects of temperature, humidity, discharge power and the gap size within the confined space on the plasma characteristics were analyzed. It was found that temperature, humidity and discharge power are important factors that affect the concentration distribution of active components and the mode transition between ozone and nitrogen oxides. Compared to open space, the concentration of ozone in confined space was relatively lower, which facilitated the formation of nitrogen oxides. In open space, the discharge was dominated by ozone initially. As the temperature,humidity and discharge power increased, nitrogen oxides in the gas-phase products were gradually detected. In confined space, nitrogen oxides can be detected at an early stage and at much higher concentrations than ozone concentration. Furthermore, as the gap of the confined space decreased, the concentration of ozone was observed to decrease while that of nitrate increased, and the rate of this concentration change was further accelerated at higher temperature and higher power. It was shown that ozone concentration decreased from 0.11 to 0.03 μmol and the nitrate concentration increased from 20.5 to 24.5 μmol when the spacing in the confined space was reduced from 5 to 1 mm, the temperature of the external discharge was controlled at 40 ℃, and the discharge power was 12 W. In summary, this study reveals the formation and transformation mechanisms of active substances in air surface micro-discharge plasma within confined space, providing foundational data for its medical applications.
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Construction and Practice of a discharge Preparation Plan for First-visit Ischemic stroke patients Based on the ADOPT model(Project No.:XJ2023005101)。
文摘Objective:To investigate the application effect of the discharge preparation plan based on the ADOPT nursing model in patients with first-visit ischemic stroke.Methods:Eighty patients with first-visit ischemic stroke admitted to our hospital from June 1,2024 to November 31,2024 were selected and divided into a control group(June 1,2024 to August 30,2024)and an intervention group(September 1,2024 to November 31,2024)according to different admission times,with 40 cases in each group.The control group received routine care and discharge guidance,while the intervention group received a discharge preparation plan based on the ADOPT model on the basis of routine care.The discharge readiness[Discharge Readiness Scale(RHDS)]of patients on the day of discharge was compared.Self-efficacy at 3 months after discharge[evaluated using the Chronic Disease Self-Efficacy Scale(SECD6)],activities of daily living[evaluated using the Barthel index(BI)],blood glucose and blood pressure indicators(diastolic blood pressure,systolic blood pressure,FPG,2 h PG),and readmission rate within 3 months after discharge were also compared between the two groups.Results:On the day of discharge,the RHDS-related dimension scores of the intervention group were higher than those of the control group(t=17.993,8.560,10.243,p<0.05);Three months after discharge,the SECD6 score and BI score of the intervention group were higher than those of the control group(t=8.910,10.899,both p<0.05);Systolic blood pressure,diastolic blood pressure,FPG and 2h PG in the intervention group were lower than those in the control group(t=8.868,4.794,3.829,7.121,all p<0.05);Within 3 months after discharge,the readmission rate of the intervention group was lower than that of the control group(χ^(2)=5.165,2 p<0.05).Conclusion:The discharge preparation plan based on the ADOPT nursing model,when applied to patients with first-visit ischemic stroke,can not only enhance self-efficacy and discharge preparation,improve activities of daily living,but also optimize blood glucose and blood pressure indicators and reduce the readmission rate,which is worthy of reference.
基金National Key R&D Program of China(No.2020YFC2201000).
文摘Research has been carried out on a hybrid discharge ion thruster,aiming to combine the advantages of Direct Current(DC)discharge ion thrusters(known for their high thrust density and high power supply efficiency)with microwave discharge ion thrusters(which do not require a hollow cathode and are capable of efficient ionization at low pressures).Comparative experiments with different anode structures and single-probe diagnostics revealed that applying a DC bias voltage created a new ionization zone based on microwave discharge.This DC bias increased the sheath potential of the screen grid and led to an elevation in electron temperature and plasma density.It is speculated that the reduced loss of high-energy electrons generated by microwave discharge at the screen grid is the primary reason for the enhanced discharge.By adding a DC bias of approximately 50 V to the microwave discharge,the screen grid current was doubled without a significant increase in discharge power consumption.Under appropriate bias voltages that consider minimizing ion sputtering,DC bias holds promise as a design approach to increase the extracted beam current in microwave ion thrusters.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12375250,11875121,51977057,11805013)the Natural Science Foundation of Hebei Province,China(Grant Nos.A2020201025 and A2022201036)+3 种基金the Hebei Province Optoelectronic Information Materials Laboratory Performance Subsidy Fund Project(Grant No.22567634H)the Funds for Distinguished Young Scientists of Hebei Province,China(Grant No.A2012201045)the Natural Science Interdisciplinary Research Program of Hebei University(Grant Nos.DXK201908 and DXK202011)the Post-graduate’s Innovation Fund Project of Hebei University(Grant No.HBU2022bs004)。
文摘As a popular approach to producing atmospheric pressure non-thermal plasma,dielectric barrier discharge(DBD)has been extensively used in various application fields.In this paper,DBD with wavy dielectric layers is numerically simulated in atmospheric pressure helium mixed with trace nitrogen based on a fluid model.With varying relative position(phase difference(Δφ))of the wavy surfaces,there is a positive discharge and a negative discharge per voltage cycle,each of which consists of a pulse stage and a hump stage.For the pulse stage,maximal current increases with increasingΔφ.Results show that DBD with the wavy surfaces appears as discrete micro-discharges(MDs),which are self-organized to different patterns with varyingΔφ.The MDs are vertical and uniformly-spaced withΔφ=0,which are self-organized in pairs withΔφ=π/4.These MD pairs are merged into some bright wide MDs withΔφ=π/2.In addition,narrow MDs appear between tilted wide MDs withΔφ=3π/4.WithΔφ=π,the pattern is composed of wide and narrow MDs,which are vertical and appear alternately.To elucidate the formation mechanism of the patterns with differentΔφ,temporal evolutions of electron density and electric field are investigated for the positive discharge.Moreover,surface charge on the wavy dielectric layers has also been compared with differentΔφ.
基金supported by National Natural Science Foundation of China(Nos.11875121,51977057,11575050,11875014)the Hebei Province Natural Science Foundation(No.A2022201036)。
文摘This paper describes the realization of a homogeneous dielectric barrier discharge(DBD)in argon at atmospheric pressure.The effect of the morphology of the dielectric surface(especially the dielectric surface covered by hollow ceramic beads(99%Al_(2)O_(3))with different diameters)on discharge is investigated.With different dielectrics,the argon DBD presents two discharge modes:a filamentary mode and a homogeneous mode.Fast photography shows that the filamentary mode operates in a streamer discharge,and the homogeneous mode operates in a Townsend discharge regime.It is found that a homogeneous discharge can be generated within a certain voltage range.The voltage amplitude range decreases,and the breakdown voltage increases with the increase in the mean diameter of the ceramic beads.Waveforms of the total current and optical emission signal present stochastic pulses per half voltage cycle for the filamentary mode,whereas there is one single hump per half voltage cycle for the homogeneous mode.In the homogeneous mode,the intensity of the optical emission decreases with the mean diameter of the ceramic beads.The optical emission spectrum is mainly composed of atomic lines of argon and the second positive system of molecular nitrogen.It reveals that the electron density decreases with the increasing mean diameter of the ceramic beads.The vibrational temperature increases with the increasing mean diameter of the ceramic beads.It is believed that a large number of microdischarges are formed,and smaller ceramic beads have a larger activation surface area and more point discharge.Electrons liberated in the shallow well and electrons generated from microdischarges can increase the secondary electron emission coefficient of the cathode and provide initial electrons for discharge continuously.Therefore,the breakdown electric field is reduced,which contributes to easier generation of homogeneous discharge.This is confirmed by the simulation results.
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With the swift development of economy, the water quality of Beijing is becoming worse day by day and hampers the sustainable development obviously. In this paper, the current conditions of the municipal wastewater structure in the industrial sectors are analysed and discussed in terms of the indicators, such as direct wastewater\|discharge coefficient, complete wastewater\|discharge coefficient, direct discharge coefficient of COD and complete discharge coefficient of COD, by taking a year of 1990s as the base year. Some countermeasures are studied and the corresponding recommendations are put forward in order to improve the water environment in Beijing. This provides a scientific ground for coordinating the relationship between the aquatic environment and economic growth in this city.
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 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 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.
