Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulc...Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulching is commonly used in the Loess Plateau region.Incorporating slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop productivity.Combining these techniques represents a novel agricultural approach in semi-arid areas.However,the impact of this integration on soil carbon storage(SOCS),carbon footprint(CF),and economic benefits has received limited research attention.Therefore,we conducted an eight-year study(2015-2022)in the semi-arid northwestern region to quantify the effects of four treatments[urea supplied without plastic film mulching(CK-U),slow-release fertilizer supplied without plastic film mulching(CK-S),urea supplied with plastic film mulching(PM-U),and slow-release fertilizer supplied with plastic film mulching(PM-S)]on soil fertility,economic and environmental benefits.The results revealed that nitrogen fertilizer was the primary contributor to total GHG emissions(≥71.97%).Compared to other treatments,PM-S increased average grain yield by 12.01%-37.89%,water use efficiency by 9.19%-23.33%,nitrogen accumulation by 27.07%-66.19%,and net return by 6.21%-29.57%.Furthermore,PM-S decreased CF by 12.87%-44.31%and CF per net return by 14.25%-41.16%.After eight years,PM-S increased SOCS(0-40 cm)by 2.46%,while PM-U decreased it by 7.09%.These findings highlight the positive effects of PM-S on surface soil fertility,economic gains,and environmental benefits in spring maize production on the Loess Plateau,underscoring its potential for widespread adoption and application.展开更多
Ammonia(NH3)has been widely recognized as a key precursor of atmospheric secondary aerosol formation.Vehicle emission is a major source of urban atmospheric NH3.With the tightening of emission standards and the growin...Ammonia(NH3)has been widely recognized as a key precursor of atmospheric secondary aerosol formation.Vehicle emission is a major source of urban atmospheric NH3.With the tightening of emission standards and the growing trend of vehicle fleet electrification,it is imperative to update the emission factors for NH3 from real-world on-road fleets.In this study,a tunnel measurement was conducted in the urban area of Tianjin,China.The fleet-average NH3 emission factor(EF)was 11.2 mg/(km·veh),significantly lower than those in previous studies,showing the benefit of emission standard updating.Through a multiple linear regression analysis,the EFs of light-duty gasoline vehicles,light-duty diesel vehicles,and heavy-duty diesel vehicles(HDDVs)were estimated to be 5.7±0.6 mg/(km·veh),40.8±5.1 mg/(km·veh),and 160.2±16.6 mg/(km·veh),respectively.Based on the results from this study,we found that HDDVs,which comprise<3%of the total vehicles may contribute approximately 22%of total NH3 emissions in Tianjin.Our results highlight NH3 emissions from HDDVs,a previously potentially overlooked source of NH3 emissions in urban areas.The actual on-road NH3 emissions from HDDVs may exceed current expectations,posing a growing concern for the future.展开更多
Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longe...Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longer period.A multi-objective genetic algorithm(MOGA)and state of charge(SOC)region division for the batteries are introduced to solve the objective function and configuration of the system capacity,respectively.MATLAB/Simulink was used for simulation test.The optimization results show that for a 0.5 MW wind power and 0.5 MW photovoltaic system,with a combination of a 300 Ah lithium battery,a 200 Ah lead-acid battery,and a water storage tank,the proposed strategy reduces the system construction cost by approximately 18,000 yuan.Additionally,the cycle count of the electrochemical energy storage systemincreases from4515 to 4660,while the depth of discharge decreases from 55.37%to 53.65%,achieving shallow charging and discharging,thereby extending battery life and reducing grid voltage fluctuations significantly.The proposed strategy is a guide for stabilizing the grid connection of wind and solar power generation,capability allocation,and energy management of energy conservation systems.展开更多
Integrating Bayesian Optimization with Volume of Fluid (VOF) simulations, this work aims to optimize the operational conditions and geometric parameters of T-junction microchannels for target droplet sizes. Bayesian O...Integrating Bayesian Optimization with Volume of Fluid (VOF) simulations, this work aims to optimize the operational conditions and geometric parameters of T-junction microchannels for target droplet sizes. Bayesian Optimization utilizes Gaussian Process (GP) as its core model and employs an adaptive search strategy to efficiently explore and identify optimal combinations of operational parameters within a limited parameter space, thereby enabling rapid optimization of the required parameters to achieve the target droplet size. Traditional methods typically rely on manually selecting a series of operational parameters and conducting multiple simulations to gradually approach the target droplet size. This process is time-consuming and prone to getting trapped in local optima. In contrast, Bayesian Optimization adaptively adjusts its search strategy, significantly reducing computational costs and effectively exploring global optima, thus greatly improving optimization efficiency. Additionally, the study investigates the impact of rectangular rib structures within the T-junction microchannel on droplet generation, revealing how the channel geometry influences droplet formation and size. After determining the target droplet size, we further applied Bayesian Optimization to refine the rib geometry. The integration of Bayesian Optimization with computational fluid dynamics (CFD) offers a promising tool and provides new insights into the optimal design of microfluidic devices.展开更多
Production of green hydrogen through water electrolysis powered by renewable energy sources has garnered increasing attention as an attractive strategy for the storage of clean and sustainable energy.Among various ele...Production of green hydrogen through water electrolysis powered by renewable energy sources has garnered increasing attention as an attractive strategy for the storage of clean and sustainable energy.Among various electrolysis technologies,the emerging anion exchange membrane water electrolyser(AEMWE)exhibits the most potential for green hydrogen production,offering a potentially costeffective and sustainable approach that combines the advantages of high current density and fast start from proton exchange membrane water electrolyser(PEMWE)and low-cost catalyst from traditional alkaline water electrolyser(AWE)systems.Due to its relatively recent emergence over the past decade,a series of efforts are dedicated to improving the electrochemical reaction performance to accelerate the development and commercialization of AEMWE technology.A catalytic electrode comprising a gas diffusion layer(GDL)and a catalyst layer(CL)is usually called a gas diffusion electrode(GDE)that serves as a fundamental component within AEMWE,and also plays a core role in enhancing mass transfer during the electrolysis process.Inside the GDEs,bubbles nucleate and grow within the CL and then are transported through the GDL before eventually detaching to enter the electrolyte in the flow field.The transfer processes of water,gas bubbles,charges,and ions are intricately influenced by bubbles.This phenomenon is referred to as bubble-associated mass transfer.Like water management in fuel cells,effective bubble management is crucial in electrolysers,as its failure can result in various overpotential losses,such as activation losses,ohmic losses,and mass transfer losses,ultimately degrading the AEMWE performance.Despite significant advancements in the development of new materials and techniques in AEMWE,there is an urgent need for a comprehensive discussion focused on GDEs,with a particular emphasis on bubbleassociated mass transfer phenomena.This review aims to highlight recent findings regarding mass transfer in GDEs,particularly the impacts of bubble accumulation;and presents the latest advancements in designing CLs and GDLs to mitigate bubble-related issues.It is worth noting that a series of innovative bubble-free-GDE designs for water electrolysis are also emphasized in this review.This review is expected to be a valuable reference for gaining a deeper understanding of bubble-related mass transfer,especially the complex bubble behavior associated with GDEs,and for developing innovative practical strategies to advance AEMWE for green hydrogen production.展开更多
Liquid-liquid dispersion is often performed in stirred tanks,which are valued for their ease of operation,high droplet generation rate and effective droplet dispersion.Many relevant simulations use the Eulerian-Euleri...Liquid-liquid dispersion is often performed in stirred tanks,which are valued for their ease of operation,high droplet generation rate and effective droplet dispersion.Many relevant simulations use the Eulerian-Eulerian method,combining population balance equations with statistical models to forecast droplet breakage.Conversely,the Eulerian-Lagrangian(E-L)method provides precise tracking of individual droplets,which is crucial for simulating dispersion processes.However,E-L simulation faces challenges in integrating droplet breakage effectively.To address this issue,our research introduces a probabilistic approach for droplet breakages.It assumes that a longer time increases the likelihood of breakup;a droplet breaks if the calculated probability exceeds a random value from 0 to 1.Consequently,the simulated breakage frequency becomes independent of the Lagrangian time step.The Sauter mean diameter and droplet size distribution can be accurately predicted by this probabilistic approach.By closely monitoring droplet motion,we reveal the complexity of droplet trajectories and the detailed patterns of circulation in stirred tanks.These insights contribute to a deeper understanding of liquidliquid dispersion dynamics.展开更多
BACKGROUND Hepatic hemangiomas represent the most prevalent benign liver tumors.Surgical management of large symptomatic hepatic hemangiomas remains controversial and there is an increasing interest in minimally invas...BACKGROUND Hepatic hemangiomas represent the most prevalent benign liver tumors.Surgical management of large symptomatic hepatic hemangiomas remains controversial and there is an increasing interest in minimally invasive techniques,such as transcatheter arterial chemoembolization(TACE)and microwave ablation(MWA).AIM To evaluate the efficacy and safety of TACE combined with MWA for large hepatic hemangiomas.METHODS This retrospective cohort study was conducted at Peking Union Medical College Hospital between January 2015 and January 2024.Eighty-two patients with hepatic hemangiomas>5 cm were divided into two groups:Observation(TACE+MWA,n=50)and control(TACE,n=32).Tumor diameter and treatment outcomes were evaluated at baseline,12 months,and>3 years.Appropriate statistical tests were chosen based on the type and distribution of the data.RESULTS At baseline,the median tumor diameter was 8.3(range:5.0-19.2)cm in the observation group and 8.5(range:5.0-20.0)cm in the control group.The median follow up duration was 44.6(95%confidence interval:36.7-52.5)months.At 12 months post-treatment,the observation group demonstrated a higher tumor reduction ratio compared to the control group(50.98%vs 23.28%,respectively;P<0.001).The objective response rate was 93.94%in the observation group,which was significantly higher than that in the control group(33.33%)(P<0.001).No recurrence occurred in the observation group,while one case occurred in the control group.Notably,no cases of hemoglobinuria or acute kidney injury were reported in the observation group.CONCLUSION Combination treatment enhances tumor shrinkage,promotes long-term tumor control,and reduces the complications associated with MWA,thereby presenting a promising alternative to surgical resection.展开更多
Chemical short-range order(SRO)in multi-principal element alloys(MPEAs)and its unprecedented benefits on materials performance have been elucidated in recent experimental observations.Hence,manipulating the fine struc...Chemical short-range order(SRO)in multi-principal element alloys(MPEAs)and its unprecedented benefits on materials performance have been elucidated in recent experimental observations.Hence,manipulating the fine structure of SRO and its interaction with other coexisting SROs or defects becomes increasingly crucial for MPEAs design.Here,using TiZrNb,TiZrVNb,and TiZrV as the model systems,SRO and its interaction with surrounding environment,as well as its effects on mechanical properties are comprehensively explored through density functional theory-based Monte Carlo simulations.We find that both TiZrNb and TiZrVNb exhibit Ti-Zr SRO and Nb-Nb short-range clustering(SRC),whereas in TiZrV,Zr-V SRO occurs in addition to Ti-Zr SRO.SRO largely increases the modulus and the unstable stacking fault energy(USFE).At the electronic scale,SRO is found accompanied with a deeper pseudo-energy gap at Fermi level,and with a covalent bonding character between the metallic atoms.Due to the SRO-oxygen attraction,oxygen centered and Ti/Zr enriched octahedron coined as(O,2Ti,4Zr)-octahedron populates in TiZrNb-O and TiZrV-O.In TiZrVNb-O,there mainly exist two types of octahedral:(O,2Ti,4Zr)and(O,3Ti,3Zr).Quantitatively,forming these(O,Ti,Zr)-octahedra,the modulus and USFE of MPEAs are further increased compared to the individual contribution from SRO or oxygen,but the improvement does not surpass the sum of the increments induced by the two individuals.The present findings deepen the understanding of SROs and their interactions with surrounding environments,pushing forward the effective utilization of SRO in materials design.展开更多
To investigate the response of Roadside Monitoring Stations(RSs)to traffic-related air pollution,traffic and pollutant characteristics,influencing factors,and potential source characterization in Tianjin,China were de...To investigate the response of Roadside Monitoring Stations(RSs)to traffic-related air pollution,traffic and pollutant characteristics,influencing factors,and potential source characterization in Tianjin,China were determined based on roadside monitoring of real-world data conducted at RSs in 2022.The diurnal variation trend of pollutants at RSs was consistent with that at the National Monitoring Station(NM),with notably higher pollutant fluctuations during the morning and evening peak traffic times at RSs,where the average diurnal concentration was 41.46%higher than that at the NM.The generalized additive model(GAM)for nitrogen oxides(NO_(x))and carbon monoxide(CO),responding to themultiple influencing factors,performed well at RSs,with deviance explained by 86.6%and 61.4%,respectively.The synergistic effects of wind direction and speed contributed to most of the variations in NO_(x) and CO,which were 14.74%and 12.87%,respectively.Pollutant concentrations were highest under windless conditions,with pollutants originating primarily from local vehicle emissions.The model results indicated that medium-duty truck(MDT)traffic flow predominantly contributed to the variability in NO_(x) emissions,whereas passenger car(PC)traffic flow was the primary source of CO emissions from traffic variables.MDTs should be the focus of urban NO_(x) traffic emissions control.Potential-source analysis validated the results obtained from the GAM,and both analyses showed that RSs can better characterize traffic-related air pollutants.Furthermore,more stringent emission standards have effectively mitigated the release of pollutants from motor vehicles and contributed to the modernization of vehicle fleet composition,effectively decreasing CO concentrations.展开更多
Senescent macrophages have emerged as dynamic cells within the tumor microenvironment that significantly promote tumor progression through complex cellular and molecular functional alterations. This review explores th...Senescent macrophages have emerged as dynamic cells within the tumor microenvironment that significantly promote tumor progression through complex cellular and molecular functional alterations. This review explores the multifaceted roles of macrophage senescence in cancer, and establishes links between senescent macrophages and tumor progression from multiple perspectives, on the basis of the first comprehensive analysis of the molecular mechanisms and pathways involved. By systematically examining the diverse changes in senescent macrophages, this review integrates and analyzes their effects on tumors, thus offering a comprehensive and novel theoretical foundation, and practical insights for cancer treatment. Notably, by integrating current molecular research and therapeutic advancements, we summarize novel therapeutic strategies targeting senescent macrophages, including senolytics, senescence modulators, and cutting-edge immunotherapies, thereby highlighting the potential of senescent macrophages as a therapeutic target and introducing new opportunities for cancer treatment.展开更多
This paper presents a new capacity planning method that utilizes the complementary characteristics of wind and solar power output.It addresses the limitations of relying on a single metric for a comprehensive assessme...This paper presents a new capacity planning method that utilizes the complementary characteristics of wind and solar power output.It addresses the limitations of relying on a single metric for a comprehensive assessment of complementarity.To enable more accurate predictions of the optimal wind-solar ratio,a comprehensive complementarity rate is proposed,which allows for the optimization of wind-solar capacity based on this measure.Initially,the Clayton Copula function is employed to create a joint probability distribution model for wind and solar power,enabling the calculation of the comprehensive complementarity rate.Following this,a joint planning model is developed to enhance the system’s economy and reliability.The goal is to minimize total costs,load deficit rates,and curtailment rates by applying an ImprovedMulti-Objective Particle SwarmOptimization algorithm(IMOPSO).Results show that when the proportion of wind power reaches 70%,the comprehensive complementarity rate is optimized.This optimization leads to a 14.83%reduction in total costs and a 9.27%decrease in curtailment rates.Compared to existing studies,this paper offers a multidimensional analysis of the relationship between the comprehensive complementarity rate and the optimal wind-solar ratio,thereby improving predictive accuracy and providing a valuable reference for research on the correlation between wind and solar power.展开更多
基金supported by the National Natural Science Foundation of China(No.32071980)the Key Projects of Shaanxi Agricultural Collaborative Innovation and Extension Alliance(No.LMZD202201)+1 种基金the Key R&D Project in Shaanxi Province(No.2021LLRH-07)Shaanxi Natural Scientific Basic Research Program project(No.2022JQ-157).
文摘Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulching is commonly used in the Loess Plateau region.Incorporating slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop productivity.Combining these techniques represents a novel agricultural approach in semi-arid areas.However,the impact of this integration on soil carbon storage(SOCS),carbon footprint(CF),and economic benefits has received limited research attention.Therefore,we conducted an eight-year study(2015-2022)in the semi-arid northwestern region to quantify the effects of four treatments[urea supplied without plastic film mulching(CK-U),slow-release fertilizer supplied without plastic film mulching(CK-S),urea supplied with plastic film mulching(PM-U),and slow-release fertilizer supplied with plastic film mulching(PM-S)]on soil fertility,economic and environmental benefits.The results revealed that nitrogen fertilizer was the primary contributor to total GHG emissions(≥71.97%).Compared to other treatments,PM-S increased average grain yield by 12.01%-37.89%,water use efficiency by 9.19%-23.33%,nitrogen accumulation by 27.07%-66.19%,and net return by 6.21%-29.57%.Furthermore,PM-S decreased CF by 12.87%-44.31%and CF per net return by 14.25%-41.16%.After eight years,PM-S increased SOCS(0-40 cm)by 2.46%,while PM-U decreased it by 7.09%.These findings highlight the positive effects of PM-S on surface soil fertility,economic gains,and environmental benefits in spring maize production on the Loess Plateau,underscoring its potential for widespread adoption and application.
基金supported by the National key research and development program of China(No.2022YFE0135000)the National Natural Science Foundation of China(No.42175123)the Natural Science Foundation of Tianjin(No.23JCJQJC00170).
文摘Ammonia(NH3)has been widely recognized as a key precursor of atmospheric secondary aerosol formation.Vehicle emission is a major source of urban atmospheric NH3.With the tightening of emission standards and the growing trend of vehicle fleet electrification,it is imperative to update the emission factors for NH3 from real-world on-road fleets.In this study,a tunnel measurement was conducted in the urban area of Tianjin,China.The fleet-average NH3 emission factor(EF)was 11.2 mg/(km·veh),significantly lower than those in previous studies,showing the benefit of emission standard updating.Through a multiple linear regression analysis,the EFs of light-duty gasoline vehicles,light-duty diesel vehicles,and heavy-duty diesel vehicles(HDDVs)were estimated to be 5.7±0.6 mg/(km·veh),40.8±5.1 mg/(km·veh),and 160.2±16.6 mg/(km·veh),respectively.Based on the results from this study,we found that HDDVs,which comprise<3%of the total vehicles may contribute approximately 22%of total NH3 emissions in Tianjin.Our results highlight NH3 emissions from HDDVs,a previously potentially overlooked source of NH3 emissions in urban areas.The actual on-road NH3 emissions from HDDVs may exceed current expectations,posing a growing concern for the future.
基金supported by a Horizontal Project on the Development of a Hybrid Energy Storage Simulation Model for Wind Power Based on an RT-LAB Simulation System(PH2023000190)the Inner Mongolia Natural Science Foundation Project and the Optimization of Exergy Efficiency of a Hybrid Energy Storage System with Crossover Control for Wind Power(2023JQ04).
文摘Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longer period.A multi-objective genetic algorithm(MOGA)and state of charge(SOC)region division for the batteries are introduced to solve the objective function and configuration of the system capacity,respectively.MATLAB/Simulink was used for simulation test.The optimization results show that for a 0.5 MW wind power and 0.5 MW photovoltaic system,with a combination of a 300 Ah lithium battery,a 200 Ah lead-acid battery,and a water storage tank,the proposed strategy reduces the system construction cost by approximately 18,000 yuan.Additionally,the cycle count of the electrochemical energy storage systemincreases from4515 to 4660,while the depth of discharge decreases from 55.37%to 53.65%,achieving shallow charging and discharging,thereby extending battery life and reducing grid voltage fluctuations significantly.The proposed strategy is a guide for stabilizing the grid connection of wind and solar power generation,capability allocation,and energy management of energy conservation systems.
基金support from National Key Research and Development Program of China(2023YFC3905400)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA0490102)National Natural Science Foundation of China(22178354,2242100322408374).
文摘Integrating Bayesian Optimization with Volume of Fluid (VOF) simulations, this work aims to optimize the operational conditions and geometric parameters of T-junction microchannels for target droplet sizes. Bayesian Optimization utilizes Gaussian Process (GP) as its core model and employs an adaptive search strategy to efficiently explore and identify optimal combinations of operational parameters within a limited parameter space, thereby enabling rapid optimization of the required parameters to achieve the target droplet size. Traditional methods typically rely on manually selecting a series of operational parameters and conducting multiple simulations to gradually approach the target droplet size. This process is time-consuming and prone to getting trapped in local optima. In contrast, Bayesian Optimization adaptively adjusts its search strategy, significantly reducing computational costs and effectively exploring global optima, thus greatly improving optimization efficiency. Additionally, the study investigates the impact of rectangular rib structures within the T-junction microchannel on droplet generation, revealing how the channel geometry influences droplet formation and size. After determining the target droplet size, we further applied Bayesian Optimization to refine the rib geometry. The integration of Bayesian Optimization with computational fluid dynamics (CFD) offers a promising tool and provides new insights into the optimal design of microfluidic devices.
基金support from the National Natural Science Foundation of China(Grant No.52006029)the Promotion Foundation for Young Science and Technology Talents in Jilin Province(Grant No.QT202113)+2 种基金the Special Foundation of Industrial Innovation in Jilin Province(Grant No.2019C056-2)the Special Foundation for Outstanding Young Talents Training in Jilin(Grant No.20200104107)the UK EPSRC(EP/W03784X/1)。
文摘Production of green hydrogen through water electrolysis powered by renewable energy sources has garnered increasing attention as an attractive strategy for the storage of clean and sustainable energy.Among various electrolysis technologies,the emerging anion exchange membrane water electrolyser(AEMWE)exhibits the most potential for green hydrogen production,offering a potentially costeffective and sustainable approach that combines the advantages of high current density and fast start from proton exchange membrane water electrolyser(PEMWE)and low-cost catalyst from traditional alkaline water electrolyser(AWE)systems.Due to its relatively recent emergence over the past decade,a series of efforts are dedicated to improving the electrochemical reaction performance to accelerate the development and commercialization of AEMWE technology.A catalytic electrode comprising a gas diffusion layer(GDL)and a catalyst layer(CL)is usually called a gas diffusion electrode(GDE)that serves as a fundamental component within AEMWE,and also plays a core role in enhancing mass transfer during the electrolysis process.Inside the GDEs,bubbles nucleate and grow within the CL and then are transported through the GDL before eventually detaching to enter the electrolyte in the flow field.The transfer processes of water,gas bubbles,charges,and ions are intricately influenced by bubbles.This phenomenon is referred to as bubble-associated mass transfer.Like water management in fuel cells,effective bubble management is crucial in electrolysers,as its failure can result in various overpotential losses,such as activation losses,ohmic losses,and mass transfer losses,ultimately degrading the AEMWE performance.Despite significant advancements in the development of new materials and techniques in AEMWE,there is an urgent need for a comprehensive discussion focused on GDEs,with a particular emphasis on bubbleassociated mass transfer phenomena.This review aims to highlight recent findings regarding mass transfer in GDEs,particularly the impacts of bubble accumulation;and presents the latest advancements in designing CLs and GDLs to mitigate bubble-related issues.It is worth noting that a series of innovative bubble-free-GDE designs for water electrolysis are also emphasized in this review.This review is expected to be a valuable reference for gaining a deeper understanding of bubble-related mass transfer,especially the complex bubble behavior associated with GDEs,and for developing innovative practical strategies to advance AEMWE for green hydrogen production.
基金support from the National Key Research and Development Program of China,China(2023YFE0106600)the National Natural Science Foundation of China,China(22421003,22178354,21925805)funding from FFG(Austria)under project“ABATE”(903872).
文摘Liquid-liquid dispersion is often performed in stirred tanks,which are valued for their ease of operation,high droplet generation rate and effective droplet dispersion.Many relevant simulations use the Eulerian-Eulerian method,combining population balance equations with statistical models to forecast droplet breakage.Conversely,the Eulerian-Lagrangian(E-L)method provides precise tracking of individual droplets,which is crucial for simulating dispersion processes.However,E-L simulation faces challenges in integrating droplet breakage effectively.To address this issue,our research introduces a probabilistic approach for droplet breakages.It assumes that a longer time increases the likelihood of breakup;a droplet breaks if the calculated probability exceeds a random value from 0 to 1.Consequently,the simulated breakage frequency becomes independent of the Lagrangian time step.The Sauter mean diameter and droplet size distribution can be accurately predicted by this probabilistic approach.By closely monitoring droplet motion,we reveal the complexity of droplet trajectories and the detailed patterns of circulation in stirred tanks.These insights contribute to a deeper understanding of liquidliquid dispersion dynamics.
基金Supported by the Peking Union Medical College Hospital Central High-Level Hospital Clinical Research Project,No.2022-PUMCH-B-069。
文摘BACKGROUND Hepatic hemangiomas represent the most prevalent benign liver tumors.Surgical management of large symptomatic hepatic hemangiomas remains controversial and there is an increasing interest in minimally invasive techniques,such as transcatheter arterial chemoembolization(TACE)and microwave ablation(MWA).AIM To evaluate the efficacy and safety of TACE combined with MWA for large hepatic hemangiomas.METHODS This retrospective cohort study was conducted at Peking Union Medical College Hospital between January 2015 and January 2024.Eighty-two patients with hepatic hemangiomas>5 cm were divided into two groups:Observation(TACE+MWA,n=50)and control(TACE,n=32).Tumor diameter and treatment outcomes were evaluated at baseline,12 months,and>3 years.Appropriate statistical tests were chosen based on the type and distribution of the data.RESULTS At baseline,the median tumor diameter was 8.3(range:5.0-19.2)cm in the observation group and 8.5(range:5.0-20.0)cm in the control group.The median follow up duration was 44.6(95%confidence interval:36.7-52.5)months.At 12 months post-treatment,the observation group demonstrated a higher tumor reduction ratio compared to the control group(50.98%vs 23.28%,respectively;P<0.001).The objective response rate was 93.94%in the observation group,which was significantly higher than that in the control group(33.33%)(P<0.001).No recurrence occurred in the observation group,while one case occurred in the control group.Notably,no cases of hemoglobinuria or acute kidney injury were reported in the observation group.CONCLUSION Combination treatment enhances tumor shrinkage,promotes long-term tumor control,and reduces the complications associated with MWA,thereby presenting a promising alternative to surgical resection.
基金financially supported by the National Natural Science Foundation of China(No.52173216)CNPC Science and Technology Project"Research and Development of Corrosion Resistant Materials for Extreme Environments"(No.2023ZZ11-02).
文摘Chemical short-range order(SRO)in multi-principal element alloys(MPEAs)and its unprecedented benefits on materials performance have been elucidated in recent experimental observations.Hence,manipulating the fine structure of SRO and its interaction with other coexisting SROs or defects becomes increasingly crucial for MPEAs design.Here,using TiZrNb,TiZrVNb,and TiZrV as the model systems,SRO and its interaction with surrounding environment,as well as its effects on mechanical properties are comprehensively explored through density functional theory-based Monte Carlo simulations.We find that both TiZrNb and TiZrVNb exhibit Ti-Zr SRO and Nb-Nb short-range clustering(SRC),whereas in TiZrV,Zr-V SRO occurs in addition to Ti-Zr SRO.SRO largely increases the modulus and the unstable stacking fault energy(USFE).At the electronic scale,SRO is found accompanied with a deeper pseudo-energy gap at Fermi level,and with a covalent bonding character between the metallic atoms.Due to the SRO-oxygen attraction,oxygen centered and Ti/Zr enriched octahedron coined as(O,2Ti,4Zr)-octahedron populates in TiZrNb-O and TiZrV-O.In TiZrVNb-O,there mainly exist two types of octahedral:(O,2Ti,4Zr)and(O,3Ti,3Zr).Quantitatively,forming these(O,Ti,Zr)-octahedra,the modulus and USFE of MPEAs are further increased compared to the individual contribution from SRO or oxygen,but the improvement does not surpass the sum of the increments induced by the two individuals.The present findings deepen the understanding of SROs and their interactions with surrounding environments,pushing forward the effective utilization of SRO in materials design.
基金supported by the National Key Research and Development Program of China(Nos.2023YFC3707301 and 2023YFC3705400)the Fundamental Research Funds for the Central Universities(Nos.ZB23003425 and 63211075)。
文摘To investigate the response of Roadside Monitoring Stations(RSs)to traffic-related air pollution,traffic and pollutant characteristics,influencing factors,and potential source characterization in Tianjin,China were determined based on roadside monitoring of real-world data conducted at RSs in 2022.The diurnal variation trend of pollutants at RSs was consistent with that at the National Monitoring Station(NM),with notably higher pollutant fluctuations during the morning and evening peak traffic times at RSs,where the average diurnal concentration was 41.46%higher than that at the NM.The generalized additive model(GAM)for nitrogen oxides(NO_(x))and carbon monoxide(CO),responding to themultiple influencing factors,performed well at RSs,with deviance explained by 86.6%and 61.4%,respectively.The synergistic effects of wind direction and speed contributed to most of the variations in NO_(x) and CO,which were 14.74%and 12.87%,respectively.Pollutant concentrations were highest under windless conditions,with pollutants originating primarily from local vehicle emissions.The model results indicated that medium-duty truck(MDT)traffic flow predominantly contributed to the variability in NO_(x) emissions,whereas passenger car(PC)traffic flow was the primary source of CO emissions from traffic variables.MDTs should be the focus of urban NO_(x) traffic emissions control.Potential-source analysis validated the results obtained from the GAM,and both analyses showed that RSs can better characterize traffic-related air pollutants.Furthermore,more stringent emission standards have effectively mitigated the release of pollutants from motor vehicles and contributed to the modernization of vehicle fleet composition,effectively decreasing CO concentrations.
基金supported by grants from the Postdoctoral Science Foundation of China (Grant No. 2020M672072)。
文摘Senescent macrophages have emerged as dynamic cells within the tumor microenvironment that significantly promote tumor progression through complex cellular and molecular functional alterations. This review explores the multifaceted roles of macrophage senescence in cancer, and establishes links between senescent macrophages and tumor progression from multiple perspectives, on the basis of the first comprehensive analysis of the molecular mechanisms and pathways involved. By systematically examining the diverse changes in senescent macrophages, this review integrates and analyzes their effects on tumors, thus offering a comprehensive and novel theoretical foundation, and practical insights for cancer treatment. Notably, by integrating current molecular research and therapeutic advancements, we summarize novel therapeutic strategies targeting senescent macrophages, including senolytics, senescence modulators, and cutting-edge immunotherapies, thereby highlighting the potential of senescent macrophages as a therapeutic target and introducing new opportunities for cancer treatment.
基金This work was supported by Inner Mongolia Natural Science Foundation Project and the Optimization of Exergy Efficiency of a Hybrid Energy Storage System with Crossover Control for Wind Power(2023JQ04).
文摘This paper presents a new capacity planning method that utilizes the complementary characteristics of wind and solar power output.It addresses the limitations of relying on a single metric for a comprehensive assessment of complementarity.To enable more accurate predictions of the optimal wind-solar ratio,a comprehensive complementarity rate is proposed,which allows for the optimization of wind-solar capacity based on this measure.Initially,the Clayton Copula function is employed to create a joint probability distribution model for wind and solar power,enabling the calculation of the comprehensive complementarity rate.Following this,a joint planning model is developed to enhance the system’s economy and reliability.The goal is to minimize total costs,load deficit rates,and curtailment rates by applying an ImprovedMulti-Objective Particle SwarmOptimization algorithm(IMOPSO).Results show that when the proportion of wind power reaches 70%,the comprehensive complementarity rate is optimized.This optimization leads to a 14.83%reduction in total costs and a 9.27%decrease in curtailment rates.Compared to existing studies,this paper offers a multidimensional analysis of the relationship between the comprehensive complementarity rate and the optimal wind-solar ratio,thereby improving predictive accuracy and providing a valuable reference for research on the correlation between wind and solar power.