The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated cata...The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated catalytic activity and minimal energy consumption continues to pose a significant challenge.In this research,Fluorine-doped copper-carbon(F/Cu-GAC)particle electrodes were effectively synthesized through an impregnationcalcination technique,utilizing granular activated carbon as the carrier and fluorinedoped modified copper oxides as the catalytic agents.The particle electrodes were subsequently utilized to promote the degradation of 2,4,6-trichlorophenol(2,4,6-TCP)in a threedimensional electrocatalytic reactor(3DER).The F/Cu-GAC particle electrodes were polarized under the action of electric field,which promoted the heterogeneous Fenton-like reaction in which H2O2 generated by two-electron oxygen reduction reaction(2e-ORR)of O_(2) was catalytically decomposed to·OH.The 3DER equipped with F/Cu-GAC particle electrodes showed 100%removal of 2,4,6-TCP and 79.24%removal of TOC with a specific energy consumption(EC)of approximately 0.019 kWh/g·COD after 2 h of operation.The F/Cu-GAC particle electrodes exhibited an overpotential of 0.38 V and an electrochemically active surface area(ECSA)of 715 cm^(2),as determined through linear sweep voltammetry(LSV)and cyclic voltammetry(CV)assessments.These findings suggest a high level of electrocatalytic performance.Furthermore,the catalytic mechanism of the 3DER equipped with F/Cu-GAC particle electrodes was elucidated through the application of X-ray photoelectron spectroscopy(XPS),electron spin resonance(ESR),and active species capture experiments.This investigation offers a novel approach for the effective degradation of 2,4,6-TCP.展开更多
Pd modified electrodes possess problems such as easy agglomeration and low electrolytic ability,and the use of manganese dioxide(MnO_(2)) to facilitate Pd reduction of organic pollutants is just started.However,there ...Pd modified electrodes possess problems such as easy agglomeration and low electrolytic ability,and the use of manganese dioxide(MnO_(2)) to facilitate Pd reduction of organic pollutants is just started.However,there is still a limited understanding of how to match the Pd load and MnO_(2) to realize optimal dechlorination efficiency at minimum cost.Here,a Pd/MnO_(2)/Ni foam cathode was successfully fabricated and applied for the efficient electrochemical dechlorination of 2,4,6-trichlorophenol(2,4,6-TCP).The optimal electrocatalytic hydrodechlorination(ECH)performance with 2,4,6-TCP dechlorination efficiency(92.58%in 180 min)was obtained when the concentration of PdCl_(2) precipitation was 1 mmol/L,the deposition time of MnO_(2) was 300 s and cathode potential was-0.8 V.Performance influenced by the exogenous factors(e.g.,initial pH and coexisted ions)were further investigated.It was found that the neutral pH was the most favorable for ECH and a reduction in dechlorination efficiency(6%~47.6%)was observed in presence of 5 mmol/L of NO_(2)^(-),NO_(3)^(-),S^(2-)or SO_(3)^(2-).Cyclic voltammetry(CV)and quenching experiments verified the existence of three hydrogen species on Pd surface,including adsorbed atomic hydrogen(H^(*)_(ads)),absorbed atomic hydrogen(H^(*)_(abs)),and molecular hydrogen(H_(2)).And the introduction of MnO_(2)promoted the generation of atomic H^(*).Only adsorbed atomic hydrogen(H^(*)_(ads)) was confirmed that it truly facilitated the ECH process.Besides H^(*)_(ads) induced reduction,the direct reduction by cathode electrons also participated in the 2,4,6-TCP dechlorination process.Pd/MnO_(2)/Ni foam cathode shows excellent dechlorination performance,fine stability and recyclable potential,which provides strategies for the effective degradation of persistent halogenated organic pollutants in groundwater.展开更多
Adsorption of 2, 4, 6-trichlorophenol（TCP） onto the calcined Mg/Al-CO_3 layered double hydroxide（CLDH） was investigated. The prepared Mg/Al-CO_3 layered double hydroxide（LDH） and CLDH were characterized by powde...Adsorption of 2, 4, 6-trichlorophenol（TCP） onto the calcined Mg/Al-CO_3 layered double hydroxide（CLDH） was investigated. The prepared Mg/Al-CO_3 layered double hydroxide（LDH） and CLDH were characterized by powder X-ray diffraction（XRD） and thermo gravimetric analyzer-differential scanning calorimeters（TG-DSC）. Moreover, 2,4,6-trichlorophenol（TCP） was removed effectively（94.7% of removal percentage in 9h） under the optimized experimental conditions. The adsorption kinetics data fitted the pseudosecond-order model well. The Freundlich, Langmuir, and Tempkin adsorption models were applied to the experimental equilibrium adsorption data at different temperatures of solution. The adsorption data fitted the Freundlieh adsorption isotherm with good values of the correlation coefficient. A mechanism of the adsorption process is proposed according to the intraparticle diffusion model, which indicates that the overall rate of adsorption can be described as three steps.展开更多
Znx</sub>Cd1-x</sub>S solid solutions with controlled morphology have been successfully synthe-sized by a facile solution-phase method. The prepared samples were characterized by X-ray powder diffraction (...Znx</sub>Cd1-x</sub>S solid solutions with controlled morphology have been successfully synthe-sized by a facile solution-phase method. The prepared samples were characterized by X-ray powder diffraction (XRD), UV-vis diffuse reflectance spectra, X-ray photoelec-tron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission elec-tron microscopy (TEM). The photocatalytic activity of Zn<sub>x</sub>Cd<sub>1-x</sub>S was evaluated in the 2,4,6-trichlorophenol (TCP) degradation and mineralization in aqueous solution under direct solar light illumination. The experiment demonstrated that TCP was effectively degraded by more than 95% with 120 min. The results show that ZnS with Cd doping (Znx</sub>Cd1-x</sub>S) exhibits the much stronger visible light adsorption than that of pure ZnS, the light adsorption increasing as the Cd<sup>2+</sup> doping amount. These results indicate that Cd doping into a ZnS crystal lattice can result in the shift of the valence band of ZnS to a positive direction. It may lead to its higher oxidative ability than pure ZnS, which is important for organic pollutant degradation under solar light irradiation. Further-more, the photocatalytic activity studies reveal that the prepared Znx</sub>Cd1-x</sub>S nanostructures exhibit an excellent photocatalytic performance, degrading rapidly the aqueous 2,4,6-trichlorophenol solution under solar light irradiation. These results sug-gest that Znx</sub>Cd1-x</sub>S nanostructure will be a promising candidate of photocatalyst working in solar light range.展开更多
2,4,6-trichlorophenol (TCP) was firstly treated with air ions generated by electric discharge, and high dechlorination (53%) was observed after 60 min treatment, indicating that air ions are an efficient dechlorinatio...2,4,6-trichlorophenol (TCP) was firstly treated with air ions generated by electric discharge, and high dechlorination (53%) was observed after 60 min treatment, indicating that air ions are an efficient dechlorination means and might have a future in the oxidative removal of chlorinated phenols. In addition, a stepwise degradation of TCP, beginning with the formation of a major product 2,6-dichloro-1,4-benzenediol via substitution, is proposed through a detailed analysis of gas chromatography/mass spectrometry.展开更多
Designing efficient and sustainable catalyst for peroxymonosulfate(PMS)activation and refractory 2,4,6-trichlorophenol(2,4,6-TCP)removal is an imminent task.This study synthesized a novelγ-MnO_(2)/NF catalyst,which h...Designing efficient and sustainable catalyst for peroxymonosulfate(PMS)activation and refractory 2,4,6-trichlorophenol(2,4,6-TCP)removal is an imminent task.This study synthesized a novelγ-MnO_(2)/NF catalyst,which has advantages in saving manganese dioxide demand and reducing manganese leaching.Theγ-MnO_(2)/NF+PMS oxidation system achieved a 0.219 min^(−1)2,4,6-TCP apparent rate constant at 20℃,and removed>90%of 2,4,6-TCP at the 5th cycle.Both free radical identification and DFT calculations revealed that•OH and SO_(4)^(•−),rather than 1O_(2),were the dominant reactive species duringγ-MnO_(2)/NF+PMS oxidation.The results indicated that the inner-sphere complexation betweenγ-MnO_(2)/NF and PMS facilitated the formation of•OH and SO_(4)^(•−).To fill the research gap in the molecular-level dissimilarities between•OH and SO_(4)^(•−)in 2,4,6-TCP degradation mechanism,experimental testing and quantum chemical analysis methods were used.The DFT calculation found that the HAA reaction at H13 site and RAF reaction at C1 site were more favorable for both•OH and SO_(4)^(•−).For most reaction sites,SO_(4)^(•−)demonstrates greater energy barriers and substrate selectivity than•OH,attributed to steric constraints.The•OH acted as the predominant oxidative agents responsible for 2,4,6-TCP decomposition.Combining DFT calculation and intermediate identification,potential degradation routes of 2,4,6-TCP were proposed.The ecotoxicity assays verified a substantial reduction in acute toxicity of the treated 2,4,6-TCP solution.This study opens up new avenues for activating PMS withγ-MnO_(2)/NF,and helps to select preferred radical oxidation processes for optimal 2,4,6-TCP removal in practical engineering.展开更多
Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both g...Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both global and regional climates.This study assesses the performance of models participating in phase 6 of the Coupled Model Intercomparison Project in simulating interannual variability modes of Northern Hemisphere 500-hPa geopotential height during winter and summer,distinguishing predictable(potentially predictable on seasonal or longer timescales)and unpredictable(intraseasonal and essentially unpredictable at long range)components,using reanalysis data and a variance decomposition method.Although most models effectively capture unpredictable modes in reanalysis,their ability to reproduce dominant predictable modes-specifically the Pacific-North American pattern,Arctic Oscillation,and Western Pacific Oscillation in winter,and the East Atlantic and North Atlantic Oscillations in summer-varies notably.An optimal ensemble is identified to distinguish(a)predictable-external modes,dominated by external forcing,and(b)predictable-internal modes,associated with slow internal variability,during the historical period(1950-2014)and the SSP5-8.5 scenario(2036-2100).Under increased radiative forcing,the leading winter/summer predictable-external mode exhibits a more uniform spatial distribution,remarkably larger trend and annual variance,and enhanced height-sea surface temperature(SST)covariance under SSP5-8.5 compared to historical conditions.The dominant winter/summer predictable-internal modes also exhibit increased variance and height-SST covariance under SSP5-8.5,along with localized changes in spatial configuration.Minimal changes are observed in spatial distribution or variance for dominant winter/summer unpredictable modes under SSP5-8.5.This study,from a predictive perspective,deepens our understanding of model uncertainties and projected changes in circulations.展开更多
The advent of sixth-generation(6G)networks introduces unprecedented challenges in achieving seamless connectivity,ultra-low latency,and efficient resource management in highly dynamic environments.Although fifth-gener...The advent of sixth-generation(6G)networks introduces unprecedented challenges in achieving seamless connectivity,ultra-low latency,and efficient resource management in highly dynamic environments.Although fifth-generation(5G)networks transformed mobile broadband and machine-type communications at massive scales,their properties of scaling,interference management,and latency remain a limitation in dense high mobility settings.To overcome these limitations,artificial intelligence(AI)and unmanned aerial vehicles(UAVs)have emerged as potential solutions to develop versatile,dynamic,and energy-efficient communication systems.The study proposes an AI-based UAV architecture that utilizes cooperative reinforcement learning(CoRL)to manage an autonomous network.The UAVs collaborate by sharing local observations and real-time state exchanges to optimize user connectivity,movement directions,allocate power,and resource distribution.Unlike conventional centralized or autonomous methods,CoRL involves joint state sharing and conflict-sensitive reward shaping,which ensures fair coverage,less interference,and enhanced adaptability in a dynamic urban environment.Simulations conducted in smart city scenarios with 10 UAVs and 50 ground users demonstrate that the proposed CoRL-based UAV system increases user coverage by up to 10%,achieves convergence 40%faster,and reduces latency and energy consumption by 30%compared with centralized and decentralized baselines.Furthermore,the distributed nature of the algorithm ensures scalability and flexibility,making it well-suited for future large-scale 6G deployments.The results highlighted that AI-enabled UAV systems enhance connectivity,support ultra-reliable low-latency communications(URLLC),and improve 6G network efficiency.Future work will extend the framework with adaptive modulation,beamforming-aware positioning,and real-world testbed deployment.展开更多
目的分析西安汉族人群CYP2A6基因拷贝数多态性及其与吸烟行为的关联性。方法选取2021年9月—2023年6月在西安区域医学检验中心体检的西安汉族居民3500例为研究对象。根据受试者是否吸烟,将其分为吸烟组(2233例)和不吸烟组(1267例),根据...目的分析西安汉族人群CYP2A6基因拷贝数多态性及其与吸烟行为的关联性。方法选取2021年9月—2023年6月在西安区域医学检验中心体检的西安汉族居民3500例为研究对象。根据受试者是否吸烟,将其分为吸烟组(2233例)和不吸烟组(1267例),根据吸烟组受试者吸烟程度将其进一步分为轻度吸烟亚组(476例)和重度吸烟亚组(1757例)。采用TaqMan®Copy Number Assays试剂盒检测受试者CYP2A6基因拷贝数多态性。结果3500例受试者中,CYP2A6基因拷贝数为0者32例(0.91%),CYP2A6基因拷贝数为1拷贝者632例(18.06%),CYP2A6基因拷贝数为2拷贝者2737例(78.20%),CYP2A6基因拷贝数为≥3拷贝者99例(2.83%)。吸烟组CYP2A6基因拷贝数为0、1拷贝者占比低于不吸烟组,CYP2A6基因拷贝数为2拷贝、≥3拷贝者占比高于不吸烟组(P<0.05)。轻度吸烟亚组与重度吸烟亚组CYP2A6基因拷贝数多态性比较,差异无统计学意义(P>0.05)。结论西安汉族人群CYP2A6基因缺失率较高,达18.97%;西安汉族人群CYP2A6基因拷贝数多态性与吸烟行为可能存在关联,且CYP2A6基因缺失个体不易形成烟草依赖,而CYP2A6基因拷贝数多态性可能与吸烟程度不存在关联。展开更多
The neuroinflammatory response mediated by microglial activation plays an important role in the secondary nerve injury of traumatic brain injury.The post-transcriptional modification of N^(6)-methyladenosine is ubiqui...The neuroinflammatory response mediated by microglial activation plays an important role in the secondary nerve injury of traumatic brain injury.The post-transcriptional modification of N^(6)-methyladenosine is ubiquitous in the immune response of the central nervous system.The fat mass and obesity-related protein catalyzes the demethylation of N^(6)-methyladenosine modifications on mRNA and is widely expressed in various tissues,participating in the regulation of multiple diseases’biological processes.However,the role of fat mass and obesity in microglial activation and the subsequent neuroinflammatory response after traumatic brain injury is unclear.In this study,we found that the expression of fat mass and obesity was significantly down-regulated in both lipopolysaccharide-treated BV2 cells and a traumatic brain injury mouse model.After fat mass and obesity interference,BV2 cells exhibited a pro-inflammatory phenotype as shown by the increased proportion of CD11b^(+)/CD86^(+)cells and the secretion of pro-inflammatory cytokines.Fat mass and obesity-mediated N^(6)-methyladenosine demethylation accelerated the degradation of ADAM17 mRNA,while silencing of fat mass and obesity enhanced the stability of ADAM17 mRNA.Therefore,down-regulation of fat mass and obesity expression leads to the abnormally high expression of ADAM17 in microglia.These results indicate that the activation of microglia and neuroinflammatory response regulated by fat mass and obesity-related N^(6)-methyladenosine modification plays an important role in the pro-inflammatory process of secondary injury following traumatic brain injury.展开更多
The reaction mechanism and pathway of the ozonation of 2,4,6-trichlorophenol(2,4,6-TCP)in aqueous solution were investigated.The removal efficiency and the variation of H_(2)O_(2),Cl^(−),formic acid,and oxalic acid we...The reaction mechanism and pathway of the ozonation of 2,4,6-trichlorophenol(2,4,6-TCP)in aqueous solution were investigated.The removal efficiency and the variation of H_(2)O_(2),Cl^(−),formic acid,and oxalic acid were studied during the semi-batch ozonation experiments(con-tinuous for ozone gas supply,fixed volume of water sample).The results showed that when there was no scavenger,the removal efficiency of 0.1 mmol/L 2,4,6-TCP could reach 99%within 6 min by adding 24 mg/L ozone.The reaction of molecular ozone with 2,4,6-TCP resulted in the formation of H2O2.The maximal concentration of H_(2)O_(2) detected during the ozonation could reach 22.5%of the original concentration of 2,4,6-TCP.The reaction of ozone with H_(2)O_(2) resulted in the generation of a lot of OH·radicals.Therefore,2,4,6-TCP was degraded to formic acid and oxalic acid by ozone and OH·radicals together.With the inhibition of OH·radicals,ozone molecule firstly degraded 2,4,6-TCP to form chlorinated quinone,which was subsequently oxidized to formic acid and oxalic acid.Two reaction pathways of the degradation of 2,4,6-TCP by ozone and O_(3)/OH·were proposed in this study.展开更多
基金supported by Guangxi Science and Technology Major Program(No.AA23073008)Hubei Key Laboratory of Water System Science for Sponge City Construction(Wuhan University)(No.2023–05)Nanning Innovation and Entrepreneur Leading Talent Project(No.2021001).
文摘The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated catalytic activity and minimal energy consumption continues to pose a significant challenge.In this research,Fluorine-doped copper-carbon(F/Cu-GAC)particle electrodes were effectively synthesized through an impregnationcalcination technique,utilizing granular activated carbon as the carrier and fluorinedoped modified copper oxides as the catalytic agents.The particle electrodes were subsequently utilized to promote the degradation of 2,4,6-trichlorophenol(2,4,6-TCP)in a threedimensional electrocatalytic reactor(3DER).The F/Cu-GAC particle electrodes were polarized under the action of electric field,which promoted the heterogeneous Fenton-like reaction in which H2O2 generated by two-electron oxygen reduction reaction(2e-ORR)of O_(2) was catalytically decomposed to·OH.The 3DER equipped with F/Cu-GAC particle electrodes showed 100%removal of 2,4,6-TCP and 79.24%removal of TOC with a specific energy consumption(EC)of approximately 0.019 kWh/g·COD after 2 h of operation.The F/Cu-GAC particle electrodes exhibited an overpotential of 0.38 V and an electrochemically active surface area(ECSA)of 715 cm^(2),as determined through linear sweep voltammetry(LSV)and cyclic voltammetry(CV)assessments.These findings suggest a high level of electrocatalytic performance.Furthermore,the catalytic mechanism of the 3DER equipped with F/Cu-GAC particle electrodes was elucidated through the application of X-ray photoelectron spectroscopy(XPS),electron spin resonance(ESR),and active species capture experiments.This investigation offers a novel approach for the effective degradation of 2,4,6-TCP.
基金supported by the NSFC-JSPS joint research program(No.51961145202)the Natural Science Foundation of Heilongjiang Province,China(No.C2018035)。
文摘Pd modified electrodes possess problems such as easy agglomeration and low electrolytic ability,and the use of manganese dioxide(MnO_(2)) to facilitate Pd reduction of organic pollutants is just started.However,there is still a limited understanding of how to match the Pd load and MnO_(2) to realize optimal dechlorination efficiency at minimum cost.Here,a Pd/MnO_(2)/Ni foam cathode was successfully fabricated and applied for the efficient electrochemical dechlorination of 2,4,6-trichlorophenol(2,4,6-TCP).The optimal electrocatalytic hydrodechlorination(ECH)performance with 2,4,6-TCP dechlorination efficiency(92.58%in 180 min)was obtained when the concentration of PdCl_(2) precipitation was 1 mmol/L,the deposition time of MnO_(2) was 300 s and cathode potential was-0.8 V.Performance influenced by the exogenous factors(e.g.,initial pH and coexisted ions)were further investigated.It was found that the neutral pH was the most favorable for ECH and a reduction in dechlorination efficiency(6%~47.6%)was observed in presence of 5 mmol/L of NO_(2)^(-),NO_(3)^(-),S^(2-)or SO_(3)^(2-).Cyclic voltammetry(CV)and quenching experiments verified the existence of three hydrogen species on Pd surface,including adsorbed atomic hydrogen(H^(*)_(ads)),absorbed atomic hydrogen(H^(*)_(abs)),and molecular hydrogen(H_(2)).And the introduction of MnO_(2)promoted the generation of atomic H^(*).Only adsorbed atomic hydrogen(H^(*)_(ads)) was confirmed that it truly facilitated the ECH process.Besides H^(*)_(ads) induced reduction,the direct reduction by cathode electrons also participated in the 2,4,6-TCP dechlorination process.Pd/MnO_(2)/Ni foam cathode shows excellent dechlorination performance,fine stability and recyclable potential,which provides strategies for the effective degradation of persistent halogenated organic pollutants in groundwater.
基金Funded by the National Natural Science Foundation of China(No.21476269)
文摘Adsorption of 2, 4, 6-trichlorophenol（TCP） onto the calcined Mg/Al-CO_3 layered double hydroxide（CLDH） was investigated. The prepared Mg/Al-CO_3 layered double hydroxide（LDH） and CLDH were characterized by powder X-ray diffraction（XRD） and thermo gravimetric analyzer-differential scanning calorimeters（TG-DSC）. Moreover, 2,4,6-trichlorophenol（TCP） was removed effectively（94.7% of removal percentage in 9h） under the optimized experimental conditions. The adsorption kinetics data fitted the pseudosecond-order model well. The Freundlich, Langmuir, and Tempkin adsorption models were applied to the experimental equilibrium adsorption data at different temperatures of solution. The adsorption data fitted the Freundlieh adsorption isotherm with good values of the correlation coefficient. A mechanism of the adsorption process is proposed according to the intraparticle diffusion model, which indicates that the overall rate of adsorption can be described as three steps.
文摘Znx</sub>Cd1-x</sub>S solid solutions with controlled morphology have been successfully synthe-sized by a facile solution-phase method. The prepared samples were characterized by X-ray powder diffraction (XRD), UV-vis diffuse reflectance spectra, X-ray photoelec-tron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission elec-tron microscopy (TEM). The photocatalytic activity of Zn<sub>x</sub>Cd<sub>1-x</sub>S was evaluated in the 2,4,6-trichlorophenol (TCP) degradation and mineralization in aqueous solution under direct solar light illumination. The experiment demonstrated that TCP was effectively degraded by more than 95% with 120 min. The results show that ZnS with Cd doping (Znx</sub>Cd1-x</sub>S) exhibits the much stronger visible light adsorption than that of pure ZnS, the light adsorption increasing as the Cd<sup>2+</sup> doping amount. These results indicate that Cd doping into a ZnS crystal lattice can result in the shift of the valence band of ZnS to a positive direction. It may lead to its higher oxidative ability than pure ZnS, which is important for organic pollutant degradation under solar light irradiation. Further-more, the photocatalytic activity studies reveal that the prepared Znx</sub>Cd1-x</sub>S nanostructures exhibit an excellent photocatalytic performance, degrading rapidly the aqueous 2,4,6-trichlorophenol solution under solar light irradiation. These results sug-gest that Znx</sub>Cd1-x</sub>S nanostructure will be a promising candidate of photocatalyst working in solar light range.
基金the Alexander von Humboldt Foundation of Germany, and partly by the CAS and the NNSF of China.
文摘2,4,6-trichlorophenol (TCP) was firstly treated with air ions generated by electric discharge, and high dechlorination (53%) was observed after 60 min treatment, indicating that air ions are an efficient dechlorination means and might have a future in the oxidative removal of chlorinated phenols. In addition, a stepwise degradation of TCP, beginning with the formation of a major product 2,6-dichloro-1,4-benzenediol via substitution, is proposed through a detailed analysis of gas chromatography/mass spectrometry.
基金supported by“Pioneer and Leading Goose+X”S&T Program of Zhejiang,China(No.2025C02230)the National Natural Science Foundation of China(Nos.52400110 and 52070111).
文摘Designing efficient and sustainable catalyst for peroxymonosulfate(PMS)activation and refractory 2,4,6-trichlorophenol(2,4,6-TCP)removal is an imminent task.This study synthesized a novelγ-MnO_(2)/NF catalyst,which has advantages in saving manganese dioxide demand and reducing manganese leaching.Theγ-MnO_(2)/NF+PMS oxidation system achieved a 0.219 min^(−1)2,4,6-TCP apparent rate constant at 20℃,and removed>90%of 2,4,6-TCP at the 5th cycle.Both free radical identification and DFT calculations revealed that•OH and SO_(4)^(•−),rather than 1O_(2),were the dominant reactive species duringγ-MnO_(2)/NF+PMS oxidation.The results indicated that the inner-sphere complexation betweenγ-MnO_(2)/NF and PMS facilitated the formation of•OH and SO_(4)^(•−).To fill the research gap in the molecular-level dissimilarities between•OH and SO_(4)^(•−)in 2,4,6-TCP degradation mechanism,experimental testing and quantum chemical analysis methods were used.The DFT calculation found that the HAA reaction at H13 site and RAF reaction at C1 site were more favorable for both•OH and SO_(4)^(•−).For most reaction sites,SO_(4)^(•−)demonstrates greater energy barriers and substrate selectivity than•OH,attributed to steric constraints.The•OH acted as the predominant oxidative agents responsible for 2,4,6-TCP decomposition.Combining DFT calculation and intermediate identification,potential degradation routes of 2,4,6-TCP were proposed.The ecotoxicity assays verified a substantial reduction in acute toxicity of the treated 2,4,6-TCP solution.This study opens up new avenues for activating PMS withγ-MnO_(2)/NF,and helps to select preferred radical oxidation processes for optimal 2,4,6-TCP removal in practical engineering.
基金supported by the National Natural Science Foundation of China(Grant Nos.U2342210 and 42275043)the National Institute of Natural Hazards,Ministry of Emergency Management of China(Grant Nos.J2223806,ZDJ2024-25 and ZDJ2025-34)。
文摘Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both global and regional climates.This study assesses the performance of models participating in phase 6 of the Coupled Model Intercomparison Project in simulating interannual variability modes of Northern Hemisphere 500-hPa geopotential height during winter and summer,distinguishing predictable(potentially predictable on seasonal or longer timescales)and unpredictable(intraseasonal and essentially unpredictable at long range)components,using reanalysis data and a variance decomposition method.Although most models effectively capture unpredictable modes in reanalysis,their ability to reproduce dominant predictable modes-specifically the Pacific-North American pattern,Arctic Oscillation,and Western Pacific Oscillation in winter,and the East Atlantic and North Atlantic Oscillations in summer-varies notably.An optimal ensemble is identified to distinguish(a)predictable-external modes,dominated by external forcing,and(b)predictable-internal modes,associated with slow internal variability,during the historical period(1950-2014)and the SSP5-8.5 scenario(2036-2100).Under increased radiative forcing,the leading winter/summer predictable-external mode exhibits a more uniform spatial distribution,remarkably larger trend and annual variance,and enhanced height-sea surface temperature(SST)covariance under SSP5-8.5 compared to historical conditions.The dominant winter/summer predictable-internal modes also exhibit increased variance and height-SST covariance under SSP5-8.5,along with localized changes in spatial configuration.Minimal changes are observed in spatial distribution or variance for dominant winter/summer unpredictable modes under SSP5-8.5.This study,from a predictive perspective,deepens our understanding of model uncertainties and projected changes in circulations.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(RS-2025-00559546)supported by the IITP(Institute of Information&Coummunications Technology Planning&Evaluation)-ITRC(Information Technology Research Center)grant funded by the Korea government(Ministry of Science and ICT)(IITP-2025-RS-2023-00259004).
文摘The advent of sixth-generation(6G)networks introduces unprecedented challenges in achieving seamless connectivity,ultra-low latency,and efficient resource management in highly dynamic environments.Although fifth-generation(5G)networks transformed mobile broadband and machine-type communications at massive scales,their properties of scaling,interference management,and latency remain a limitation in dense high mobility settings.To overcome these limitations,artificial intelligence(AI)and unmanned aerial vehicles(UAVs)have emerged as potential solutions to develop versatile,dynamic,and energy-efficient communication systems.The study proposes an AI-based UAV architecture that utilizes cooperative reinforcement learning(CoRL)to manage an autonomous network.The UAVs collaborate by sharing local observations and real-time state exchanges to optimize user connectivity,movement directions,allocate power,and resource distribution.Unlike conventional centralized or autonomous methods,CoRL involves joint state sharing and conflict-sensitive reward shaping,which ensures fair coverage,less interference,and enhanced adaptability in a dynamic urban environment.Simulations conducted in smart city scenarios with 10 UAVs and 50 ground users demonstrate that the proposed CoRL-based UAV system increases user coverage by up to 10%,achieves convergence 40%faster,and reduces latency and energy consumption by 30%compared with centralized and decentralized baselines.Furthermore,the distributed nature of the algorithm ensures scalability and flexibility,making it well-suited for future large-scale 6G deployments.The results highlighted that AI-enabled UAV systems enhance connectivity,support ultra-reliable low-latency communications(URLLC),and improve 6G network efficiency.Future work will extend the framework with adaptive modulation,beamforming-aware positioning,and real-world testbed deployment.
文摘目的分析西安汉族人群CYP2A6基因拷贝数多态性及其与吸烟行为的关联性。方法选取2021年9月—2023年6月在西安区域医学检验中心体检的西安汉族居民3500例为研究对象。根据受试者是否吸烟,将其分为吸烟组(2233例)和不吸烟组(1267例),根据吸烟组受试者吸烟程度将其进一步分为轻度吸烟亚组(476例)和重度吸烟亚组(1757例)。采用TaqMan®Copy Number Assays试剂盒检测受试者CYP2A6基因拷贝数多态性。结果3500例受试者中,CYP2A6基因拷贝数为0者32例(0.91%),CYP2A6基因拷贝数为1拷贝者632例(18.06%),CYP2A6基因拷贝数为2拷贝者2737例(78.20%),CYP2A6基因拷贝数为≥3拷贝者99例(2.83%)。吸烟组CYP2A6基因拷贝数为0、1拷贝者占比低于不吸烟组,CYP2A6基因拷贝数为2拷贝、≥3拷贝者占比高于不吸烟组(P<0.05)。轻度吸烟亚组与重度吸烟亚组CYP2A6基因拷贝数多态性比较,差异无统计学意义(P>0.05)。结论西安汉族人群CYP2A6基因缺失率较高,达18.97%;西安汉族人群CYP2A6基因拷贝数多态性与吸烟行为可能存在关联,且CYP2A6基因缺失个体不易形成烟草依赖,而CYP2A6基因拷贝数多态性可能与吸烟程度不存在关联。
基金supported by grants from the Major Projects of Health Science Research Foundation for Middle-Aged and Young Scientist of Fujian Province,China,No.2022ZQNZD01010010the National Natural Science Foundation of China,No.82371390Fujian Province Scientific Foundation,No.2023J01725(all to XC).
文摘The neuroinflammatory response mediated by microglial activation plays an important role in the secondary nerve injury of traumatic brain injury.The post-transcriptional modification of N^(6)-methyladenosine is ubiquitous in the immune response of the central nervous system.The fat mass and obesity-related protein catalyzes the demethylation of N^(6)-methyladenosine modifications on mRNA and is widely expressed in various tissues,participating in the regulation of multiple diseases’biological processes.However,the role of fat mass and obesity in microglial activation and the subsequent neuroinflammatory response after traumatic brain injury is unclear.In this study,we found that the expression of fat mass and obesity was significantly down-regulated in both lipopolysaccharide-treated BV2 cells and a traumatic brain injury mouse model.After fat mass and obesity interference,BV2 cells exhibited a pro-inflammatory phenotype as shown by the increased proportion of CD11b^(+)/CD86^(+)cells and the secretion of pro-inflammatory cytokines.Fat mass and obesity-mediated N^(6)-methyladenosine demethylation accelerated the degradation of ADAM17 mRNA,while silencing of fat mass and obesity enhanced the stability of ADAM17 mRNA.Therefore,down-regulation of fat mass and obesity expression leads to the abnormally high expression of ADAM17 in microglia.These results indicate that the activation of microglia and neuroinflammatory response regulated by fat mass and obesity-related N^(6)-methyladenosine modification plays an important role in the pro-inflammatory process of secondary injury following traumatic brain injury.
基金This work was supported by the China Postdoctoral Science Foundation and the National Natural Science Foundation of China(Grant No.50325824).
文摘The reaction mechanism and pathway of the ozonation of 2,4,6-trichlorophenol(2,4,6-TCP)in aqueous solution were investigated.The removal efficiency and the variation of H_(2)O_(2),Cl^(−),formic acid,and oxalic acid were studied during the semi-batch ozonation experiments(con-tinuous for ozone gas supply,fixed volume of water sample).The results showed that when there was no scavenger,the removal efficiency of 0.1 mmol/L 2,4,6-TCP could reach 99%within 6 min by adding 24 mg/L ozone.The reaction of molecular ozone with 2,4,6-TCP resulted in the formation of H2O2.The maximal concentration of H_(2)O_(2) detected during the ozonation could reach 22.5%of the original concentration of 2,4,6-TCP.The reaction of ozone with H_(2)O_(2) resulted in the generation of a lot of OH·radicals.Therefore,2,4,6-TCP was degraded to formic acid and oxalic acid by ozone and OH·radicals together.With the inhibition of OH·radicals,ozone molecule firstly degraded 2,4,6-TCP to form chlorinated quinone,which was subsequently oxidized to formic acid and oxalic acid.Two reaction pathways of the degradation of 2,4,6-TCP by ozone and O_(3)/OH·were proposed in this study.
