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
The interfacial properties of Schottky contacts crucially affect the performance of power devices. While a few studies have explored the impact of fluorine on Schottky contacts, a comprehensive theoretical explanation...The interfacial properties of Schottky contacts crucially affect the performance of power devices. While a few studies have explored the impact of fluorine on Schottky contacts, a comprehensive theoretical explanation supported by experimental evidence remains lacking. This work investigates the effects of fluorine incorporation and electrothermal annealing(ETA) on the current transport process at Ni/β-Ga_(2)O_(3) Schottky contacts. X-ray photoelectron spectroscopy and first-principles calculations confirm the presence of fluorine substitutions for oxygen and oxygen vacancies and their lowering effect on the Schottky barrier heights. Additionally, accurate electrothermal hybrid TCAD simulations validates the extremely short-duration high temperatures(683 K) induced by ETA, which facilitates lattice rearrangement and reduces interface trap states. The interface trap states are quantitatively resolved through frequency-dependent conductance technique, showing the trap density(DT)reduction from(0.88-2.48) × 10^(11) cm^(-2)·eV^(-1) to(0.46-2.09) × 10^(11) cm^(-2)·eV^(-1). This investigation offers critical insights into the β-Ga_(2)O_(3) contacts with the collaborative treatment and solids the promotion of high-performance β-Ga_(2)O_(3) power devices.展开更多
Background:Hua-Yi-Jie-Du formula(HYJD)is a traditional Chinese medicine that has proven effective against viral pneumonia and was extensively used during the COVID-19 pandemic.This study investigates how HYJD influenc...Background:Hua-Yi-Jie-Du formula(HYJD)is a traditional Chinese medicine that has proven effective against viral pneumonia and was extensively used during the COVID-19 pandemic.This study investigates how HYJD influences group 2 innate lymphoid cell(ILC2)and nucleotide oligomerization domain(NOD)-like receptor protein 3(NLRP3)inflammasome activation in a mouse model of viral pneumonia.Methods:A mouse model of viral pneumonia was established through the administration of polyinosinic-polycytidylic acid(poly(I:C))via nasal drops.Histopathological analysis of lung tissue was conducted,alongside enzyme-linked immunosorbent assay to quantify cytokine levels in serum and bronchoalveolar lavage fluid(BALF).Flow cytometry was employed to detect ILC2 cells in lung tissue and spleen,while immunofluorescence techniques were utilized to visualize ILC2 cells in lung tissue.Transcriptomic sequencing was performed,and the results were validated using qRT-PCR and western blot analysis.Results:HYJD significantly ameliorated inflammatory infiltration in lung tissue,decreased mucus protein secretion,and reduced the serum levels of inflammatory cytokines interleukin(IL)-1β,IL-6,and tumor necrosis factor-alpha(TNF-α).Additionally,it lowered the expression of cytokines IL-4,IL-5,IL-13,IL-25,thymic stromal lymphopoietin(TSLP),and IL-33 in BALF,and reduced the differentiation of ILC2 cells in both lung tissue and spleen.Transcriptomic analysis and experimental validation revealed that HYJD downregulated the expression of NLRP3 related genes and proteins within the NOD-like receptor signaling pathway.Conclusion:The mechanism by which HYJD intervenes in acute lung injury associated with viral pneumonia may involve the reduction of ILC2 cells differentiation and the inhibition of NLRP3 activation.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
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
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
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
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
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
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 Natural Science Foundation of China (Grant Nos. 62174019, 52302046, L2424216)the Guangdong Basic and Applied Basic Research Foundation (Grant No. 2024A1515012139)+2 种基金the Major Program (JD) of Hubei Province (Grant No. 2023BAA009)the Knowledge Innovation Program of Wuhan-Shuguang Project (Grant No. 2023010201020262)the Basic Research Program of Jiangsu (Grant No. BK20230268)。
文摘The interfacial properties of Schottky contacts crucially affect the performance of power devices. While a few studies have explored the impact of fluorine on Schottky contacts, a comprehensive theoretical explanation supported by experimental evidence remains lacking. This work investigates the effects of fluorine incorporation and electrothermal annealing(ETA) on the current transport process at Ni/β-Ga_(2)O_(3) Schottky contacts. X-ray photoelectron spectroscopy and first-principles calculations confirm the presence of fluorine substitutions for oxygen and oxygen vacancies and their lowering effect on the Schottky barrier heights. Additionally, accurate electrothermal hybrid TCAD simulations validates the extremely short-duration high temperatures(683 K) induced by ETA, which facilitates lattice rearrangement and reduces interface trap states. The interface trap states are quantitatively resolved through frequency-dependent conductance technique, showing the trap density(DT)reduction from(0.88-2.48) × 10^(11) cm^(-2)·eV^(-1) to(0.46-2.09) × 10^(11) cm^(-2)·eV^(-1). This investigation offers critical insights into the β-Ga_(2)O_(3) contacts with the collaborative treatment and solids the promotion of high-performance β-Ga_(2)O_(3) power devices.
基金supported by Yunnan Provincial Major Science and Technology Special Program(No.202402AA310035)Yunnan Key Laboratory of Dai and Yi Medicines(Yunnan University of Chinese Medicine)(No.2024JS2404)Research Foundation of Chuxiong Medical College(No.2024YYXM38).
文摘Background:Hua-Yi-Jie-Du formula(HYJD)is a traditional Chinese medicine that has proven effective against viral pneumonia and was extensively used during the COVID-19 pandemic.This study investigates how HYJD influences group 2 innate lymphoid cell(ILC2)and nucleotide oligomerization domain(NOD)-like receptor protein 3(NLRP3)inflammasome activation in a mouse model of viral pneumonia.Methods:A mouse model of viral pneumonia was established through the administration of polyinosinic-polycytidylic acid(poly(I:C))via nasal drops.Histopathological analysis of lung tissue was conducted,alongside enzyme-linked immunosorbent assay to quantify cytokine levels in serum and bronchoalveolar lavage fluid(BALF).Flow cytometry was employed to detect ILC2 cells in lung tissue and spleen,while immunofluorescence techniques were utilized to visualize ILC2 cells in lung tissue.Transcriptomic sequencing was performed,and the results were validated using qRT-PCR and western blot analysis.Results:HYJD significantly ameliorated inflammatory infiltration in lung tissue,decreased mucus protein secretion,and reduced the serum levels of inflammatory cytokines interleukin(IL)-1β,IL-6,and tumor necrosis factor-alpha(TNF-α).Additionally,it lowered the expression of cytokines IL-4,IL-5,IL-13,IL-25,thymic stromal lymphopoietin(TSLP),and IL-33 in BALF,and reduced the differentiation of ILC2 cells in both lung tissue and spleen.Transcriptomic analysis and experimental validation revealed that HYJD downregulated the expression of NLRP3 related genes and proteins within the NOD-like receptor signaling pathway.Conclusion:The mechanism by which HYJD intervenes in acute lung injury associated with viral pneumonia may involve the reduction of ILC2 cells differentiation and the inhibition of NLRP3 activation.
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 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 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.
