The structural changes in the CaO-SiO_(2)-Al_(2)O_(3)-MgO slag system with varying CaO contents were investigated through molecular dynamics(MD)simulations,and its effect on the dissolution behavior of alumina inclusi...The structural changes in the CaO-SiO_(2)-Al_(2)O_(3)-MgO slag system with varying CaO contents were investigated through molecular dynamics(MD)simulations,and its effect on the dissolution behavior of alumina inclusions was characterized by the Kullback-Leibler(KL)divergence.The slag structure analysis revealed that the[AlO]tetrahedral structure was the primary network structure in the slag.With increasing the CaO content,the non-bridge oxygen(NBO)content in the slag structure increases,and the bridge oxygen(BO)content decreases,thereby reducing the complexity of the slag network structure.Raman spectroscopy detection verifies the results of the MD simulations.The results indicated that the dissolution rate of alumina inclusions accelerates with increasing the CaO content in the slag,owing to the reduced complexity of the slag network structure and the enhanced interatomic interactions.The simulation results for the dissolution of alumina inclusions were consistent with theoretical calculations based on the slag inclusion capacity and the dimensionless dissolution rate of inclusions.Radial distribution function analysis demonstrated that the interaction between atoms in the slag system and alumina inclusions strengthens,increasing the dissolution rate of alumina inclusions.The[AlO_(6)]octahedral structure of the alumina inclusions is disrupted,forming BO structures,which in turn enhances the complexity of the slag network structure,slowing the dissolution rate of alumina inclusions.In contrast,the slag system with a higher CaO content has a relatively simpler network structure,promoting faster alumina inclusion dissolution.展开更多
China launched its first spaceborne Precipitation Measurement Radar(PMR)on the FY-3G satellite in April 2023.To achieve the scientific goal of measuring the three-dimensional precipitation structure,evaluating the qua...China launched its first spaceborne Precipitation Measurement Radar(PMR)on the FY-3G satellite in April 2023.To achieve the scientific goal of measuring the three-dimensional precipitation structure,evaluating the quantitative measurement ability of the PMR is critical.China operates more than 250 weather radars over the mainland.Consistency of the spaceborne radar with ground-based radars will enhance precipitation measurement ability,especially over oceans and mountains where observations are sparse.Additionally,the spaceborne radar can be used to evaluate the spatial and temporal homogeneity of the ground-based radar network.This paper focuses on comparing the PMR onboard the FY-3G satellite with S-band China New Generation Weather Radars(CINRADs).A comparison algorithm between the PMR and CINRADs has been developed,incorporating detailed quality control,attenuation correction,data optimization,spatiotemporal matching,non-uniform beam filling constraint,uniformity constraint,and frequency correction.The matched data in typical months of four seasons were selected to carry out the comparison.The data consistency between the PMR and CINRADs was analyzed.The correlation coefficient is 0.87,the deviation is 0.89 dB,and the standard deviation is 2.50 dB,based on 98226 matching samples.The results show the radar reflectivity of the PMR is quite comparable to that of the CINRADs,demonstrating that the PMR data quality is satisfactory and can be used to verify and correct data consistency among multiple ground-based radars.This work also paves the way for data fusion and joint application of satellite and ground radars in the future.展开更多
The pervasive accumulation of plastic waste exacerbates environmental degradation and undermines resource circularity.Selective thermal catalysis emerges as a transformative pathway for valorizing waste plastics into ...The pervasive accumulation of plastic waste exacerbates environmental degradation and undermines resource circularity.Selective thermal catalysis emerges as a transformative pathway for valorizing waste plastics into value-added chemicals,yet persistent challenges in catalytic activity and product selectivity demand systematic resolution.This review decodes cutting-edge advances in thermal depolymerization by converging two critical dimensions:atomic-scale active site engineering-where rational design of coordination features and interfacial architectures regulates C-C cleavage energetics and intermediate adsorption-and macromolecular-scale manipulation of polymer transient states-leveraging nanoconfinement effects,chain folding dynamics,and thermal fragmentation to accelerate conversion kinetics.We further highlight breakthroughs in operando char-acterization techniques that resolve time-evolving reaction coordinates across catalytic systems.By establishing multiscale structure-activity relationships linking catalyst configurations to polymer dynamics,this analysis derives design paradigms for next-generation upcycling systems.These principles enable economically viable,industrially scalable plastic valorization while charting a strategic trajectory toward carbon-circular economies.展开更多
Ground-based radar is the primary means by which severe storms are monitored and tracked;however, due to limited coverage, important data is often missed over ocean and mountainous areas. On the other hand, geostation...Ground-based radar is the primary means by which severe storms are monitored and tracked;however, due to limited coverage, important data is often missed over ocean and mountainous areas. On the other hand, geostationary(GEO)weather satellites provide continuous observations with seamless coverage with advanced imager, despite their limited capability to penetrate clouds. Combining satellite and ground-radar observations could exploit the advantages of both techniques, providing tracking capability close to that of ground radar while maintaining full spatial coverage. This study presents a novel method called Multi-dimensional satellite Observation information for Radar Estimation(MORE) to reconstruct radar composite reflectivity(CREF). Deep learning techniques are important components of MORE for estimating CREF from China's Fengyun-4B(FY-4B) GEO satellite observations. Two models are developed: an infraredonly(IR-Single) model available for all times, and a visible-infrared(VIS+IR) model for daytime applications. These models incorporate multi-dimensional satellite observation information, including temporal, spatial, spectral, and viewing angle information, to enhance the accuracy of radar echo reconstruction. Results demonstrate that the VIS+IR model outperforms the IR-Single model, and both models achieves a root-mean-square error(RMSE) of less than 6 dBZ and a coefficient of determination(R~2) of greater than 0.7. The models effectively reconstruct radar echoes, including strong echoes exceeding 50 dBZ, and show good agreement with precipitation data in radar-blind areas. This study offers a valuable solution for severe weather monitoring and tracking in regions lacking ground-based radar observations, and provides a potential tool for enhanced data assimilation in numerical weather prediction(NWP) models.展开更多
A RadioFrequency Quadrupole(RFQ)cooler-buncher system was developed and implemented in a collinear laser spectroscopy setup.This system converts a continuous ion beam into short bunches while enhancing the beam qualit...A RadioFrequency Quadrupole(RFQ)cooler-buncher system was developed and implemented in a collinear laser spectroscopy setup.This system converts a continuous ion beam into short bunches while enhancing the beam quality and reducing the energy spread.The functionality of the RFQ cooler buncher was verified through offline tests with stable rubidium and indium beams delivered from a surface ion source and a laser ablation ion source,respectively.Bunched ion beams with a full width at half maximum of approximately 2μs in the time-of-flight spectrum were successfully achieved with a transmission efficiency exceeding 60%.The implementation of the RFQ cooler-buncher system also significantly improved the overall transmission efficiency of the collinear laser spectroscopy setup.展开更多
Precipitable water vapor(PWV)is a key component of the Earth’s climate system,playing a vital role in weather,climate,and hydrological cycling.Passive microwave remote sensing offers a promising approach to measure a...Precipitable water vapor(PWV)is a key component of the Earth’s climate system,playing a vital role in weather,climate,and hydrological cycling.Passive microwave remote sensing offers a promising approach to measure all-sky PWV,though it remains challenging over land.Building on our previous development of a machine learning algorithm,we have created a global terrestrial PWV dataset using measurements from the MicroWave Radiation Imager(MWRI)aboard three FY-3 satellite series(FY-3B,FY-3C and FY-3D).The dataset spans from 2012 to 2020 at a spatial resolution of 0.25°×0.25°.It was validated against SuomiNet GPS and IGRA2(Integrated Global Radiosonde Archive Version 2)PWV products,achieving root-mean-square errors(RMSEs)of 4.47 and 3.89 mm,respectively,with RMSE values ranging from 2.90 to 5.49 mm across diverse surface conditions.As an all-weather PWV product with high-precision,the MWRI PWV dataset addresses gaps in global passive microwave-based terrestrial PWV observations,offering significant value for atmospheric research,climate modeling,hydrological studies,and beyond.展开更多
The Global Precipitation Measurement(GPM)dual-frequency precipitation radar(DPR)products(Version 07A)are employed for a rigorous comparative analysis with ground-based operational weather radar(GR)networks.The reflect...The Global Precipitation Measurement(GPM)dual-frequency precipitation radar(DPR)products(Version 07A)are employed for a rigorous comparative analysis with ground-based operational weather radar(GR)networks.The reflectivity observed by GPM Ku PR is compared quantitatively against GR networks from CINRAD of China and NEXRAD of the United States,and the volume matching method is used for spatial matching.Additionally,a novel frequency correction method for all phases as well as precipitation types is used to correct the GPM Ku PR radar frequency to the GR frequency.A total of 20 GRs(including 10 from CINRAD and 10 from NEXRAD)are included in this comparative analysis.The results indicate that,compared with CINRAD matched data,NEXRAD exhibits larger biases in reflectivity when compared with the frequency-corrected Ku PR.The root-mean-square difference for CINRAD is calculated at 2.38 d B,whereas for NEXRAD it is 3.23 d B.The mean bias of CINRAD matched data is-0.16 d B,while the mean bias of NEXRAD is-2.10 d B.The mean standard deviation of bias for CINRAD is 2.15 d B,while for NEXRAD it is 2.29 d B.This study effectively assesses weather radar data in both the United States and China,which is crucial for improving the overall consistency of global precipitation estimates.展开更多
Long-term mulching has improved crop yields and farmland productivity in semiarid areas,but it has also increased greenhouse gas(GHG)emissions and depleted soil fertility.Biochar application has emerged as a promising...Long-term mulching has improved crop yields and farmland productivity in semiarid areas,but it has also increased greenhouse gas(GHG)emissions and depleted soil fertility.Biochar application has emerged as a promising solution for addressing these issues.In this study,we investigated the effects of four biochar application rates(no biochar(N)=0 t ha^(-1),low(L)=3 t ha^(-1),medium(M)=6 t ha^(-1),and high(H)=9 t ha^(-1))under film mulching and no mulching conditions over three growing seasons.We assessed the impacts on GHG emissions,soil organic carbon sequestration(SOCS),and maize yield to evaluate the productivity and sustainability of farmland ecosystems.Our results demonstrated that mulching increased maize yield(18.68-41.80%),total fixed C in straw(23.64%),grain(28.87%),and root(46.31%)biomass,and GHG emissions(CO_(2),10.78%;N_(2)O,3.41%),while reducing SOCS(6.57%)and GHG intensity(GHGI;13.61%).Under mulching,biochar application significantly increased maize yield(10.20%),total fixed C in straw(17.97%),grain(17.69%)and root(16.75%)biomass,and SOCS(4.78%).Moreover,it reduced the GHG emissions(CO_(2),3.09%;N_(2)O,6.36%)and GHGI(12.28%).These effects correlated with the biochar addition rate,with the optimal rate being 9.0 t ha^(-1).In conclusion,biochar application reduces CO_(2) and N_(2)O emissions,enhances CH_(4) absorption,and improves maize yield under film mulching.It also improves the soil carbon fixation capacity while mitigating the warming potential,making it a promising sustainable management method for mulched farmland in semiarid areas.展开更多
Magnolol,a compound extracted from Magnolia officinalis,demonstrates potential efficacy in addressing metabolic dysfunction and cardiovascular diseases.Its biological activities encompass anti-inflammatory,antioxidant...Magnolol,a compound extracted from Magnolia officinalis,demonstrates potential efficacy in addressing metabolic dysfunction and cardiovascular diseases.Its biological activities encompass anti-inflammatory,antioxidant,anticoagulant,and anti-diabetic effects.Growth/differentiation factor-15(GDF-15),a member of the transforming growth factorβsuperfamily,is considered a potential therapeutic target for metabolic disorders.This study investigated the impact of magnolol on GDF-15 production and its underlying mechanism.The research examined the pharmacological effect of magnolol on GDF-15 expression in vitro and in vivo,and determined the involvement of endoplasmic reticulum(ER)stress signaling in this process.Luciferase reporter assays,chromatin immunoprecipitation,and in vitro DNA binding assays were employed to examine the regulation of GDF-15 by activating transcription factor 4(ATF4),CCAAT enhancer binding proteinγ(CEBPG),and CCCTC-binding factor(CTCF).The study also investigated the effect of magnolol and ATF4 on the activity of a putative enhancer located in the intron of the GDF-15 gene,as well as the influence of single nucleotide polymorphisms(SNPs)on magnolol and ATF4-induced transcription activity.Results demonstrated that magnolol triggers GDF-15 production in endothelial cells(ECs),hepatoma cell line G2(HepG2)and hepatoma cell line 3B(Hep3B)cell lines,and primary mouse hepatocytes.The cooperative binding of ATF4 and CEBPG upstream of the GDF-15 gene or the E1944285 enhancer located in the intron led to full-power transcription of the GDF-15 gene.SNP alleles were found to impact the magnolol and ATF4-induced transcription activity of GDF-15.In high-fat diet ApoE^(-/-)mice,administration of magnolol induced GDF-15 production and partially suppressed appetite through GDF-15.These findings suggest that magnolol regulates GDF-15 expression through priming of promoter and enhancer activity,indicating its potential as a drug for the treatment of metabolic disorders.展开更多
Background:Dry eye disease(DED)predominantly results from elevated tear film os-molarity,which can not only cause ocular inconvenience but may lead to visual impair-ments,severely compromising patient well-being and e...Background:Dry eye disease(DED)predominantly results from elevated tear film os-molarity,which can not only cause ocular inconvenience but may lead to visual impair-ments,severely compromising patient well-being and exerting substantial economic burdens as well.Astaxanthin(AST),a member of the xanthophylls and recognized for its robust abilities to combat inflammation and oxidation,is a common dietary sup-plement.Nonetheless,the precise molecular pathways through which AST influences DED are still poorly understood.Methods:Therapeutic targets for AST were identified using data from the GeneCards,PharmMapper,and Swiss Target Prediction databases,and STITCH datasets.Similarly,targets for dry eye disease(DED)were delineated leveraging resources such as the Therapeutic Target Database(TTD),DisGeNET,GeneCards,and OMIM databases,and DrugBank datasets.Interactions among shared targets were charted and dis-played using CytoScape 3.9.0.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were conducted to elucidate the functions of pivotal tar-gets within the protein-protein interaction network.Molecular interactions between AST and key targets were confirmed through molecular docking using AutoDock and PyMOL.Molecular dynamics simulations were performed using GROMACS 2022.3.Viability of human corneal epithelial cells(hCEC)was assessed across varying concen-trations of AST.A mouse model of experimental DED was developed using 0.1%ben-zalkonium chloride(BAC),and the animals were administered 100 mg/kg/day of AST orally for 7 days.The efficacy of the treatments was assessed through a series of di-agnostic tests to evaluate the condition of the ocular surface after the interventions.The levels of inflammation and oxidative stress were quantitatively assessed using methods such as reverse transcription-polymerase chain reaction(RT-PCR),Western blot,and immunofluorescence staining.Results:Network pharmacology suggests that AST may alleviate DED by influenc-ing oxidation-reduction signaling pathways and reducing oxidative stress provoked by BAC.In vivo experiments demonstrated an improved overall condition in AST-administered mice in contrast to the control group.Immunofluorescence staining analyses indicated a decrease in Keap1 protein in the corneal tissues of AST-treated mice and a significant increase in Nrf2 and HO-1 protein.In vitro studies demon-strated that AST significantly enhanced cell viability and suppressed reactive oxy-gen species expression under hyperosmotic(HS)conditions,thereby protecting the human corneal epithelium.Conclusion:AST is capable of shielding mice from BAC-induced DED,decelerating the progression of DED,and mitigating oxidative stress damage under HS conditions in hCEC cells.The protective impact of AST on DED may operate through stimulating the Keap1-Nrf2/HO-1 signaling pathway.Our research findings indicate that AST may be a promising treatment for DED,offering new insights into DED treatment.展开更多
With the increasing demand for high-performance metallic materials,the improvement of fatigue strength(FS)has become a crucial issue.This study focuses on the AISI 52100 steel,a material with leading fatigue performan...With the increasing demand for high-performance metallic materials,the improvement of fatigue strength(FS)has become a crucial issue.This study focuses on the AISI 52100 steel,a material with leading fatigue performance and low-cost raw material,aiming to further improve its FS.It is found that the fatigue damage mechanism of 52100 steels with different tensile strengths has undergone significant changes,and the inclusions,mainly nitride and oxide,are key factors limiting the further improvement of FS.Therefore,the size reduction and modification of inclusions were attempted through the rare earth addition and strict control of harmful elements.Combining targeted microstructure adjustment,the FS of the 52100 steel has been further enhanced to~1.6 GPa,exceeding that of other metallic materials(performed in uniaxial tension with a stress ratio of R=0.1),and thus establishing it as a standout for its exceptional performance-to-cost ratio.By clarifying the influences of different types of inclusions on fatigue performance and establishing the correlation between micro-hardness(or strength)and FS,an optimization strategy for FS improvement of the 52100 steel was proposed.The FS has been improved by approximately 187 MPa at most by implementing this strategy.These achievements provide feasible technical approaches and theoretical foundations for the anti-fatigue design of metallic materials.展开更多
We have developed a novel S-scheme heterojunction photocatalyst for the photocatalytic production of hydrogen peroxide(H_(2)O_(2))via a two-electron(2e^(-))oxygen reduction reaction.This S-scheme heterojunction Tph-Dh...We have developed a novel S-scheme heterojunction photocatalyst for the photocatalytic production of hydrogen peroxide(H_(2)O_(2))via a two-electron(2e^(-))oxygen reduction reaction.This S-scheme heterojunction Tph-Dha-COF@Nb_(2)C was fabricated via the in-situ solvothermal growth of Tph-Dha-COF nanostructures on amino-functionalized Nb_(2)C MXene nanoflakes(Nb_(2)C-NH_(2)).The integration of Nb_(2)C significantly extended the visible light absorption of Tph-Dha-COF into the near-infrared region for photocatalytic H_(2)O_(2) production.The Tph-Dha-COF@Nb_(2)C composite demonstrated efficient charge separation,rapid electron transfer,and enhanced oxygen adsorption.Consequently,the Tph-Dha-COF@Nb_(2)C heterojunction exhibited a high H_(2)O_(2) production rate of 1833μmol g^(-1) h^(-1) without sacrificial agents.In-situ Fourier transformed infrared spectroscopy and density functional theory calculations revealed the photocatalytic H_(2)O_(2) production mechanism.The generated H_(2)O_(2) demonstrated enhanced antibacterial activity.This work presents the first application of Nb_(2)C in the photocatalytic synthesis of H_(2)O_(2) and provides a novel strategy for constructing COF-based heterojunctions for photocatalytic H_(2)O_(2) generation and wastewater treatment.展开更多
Membrane electrode assembly(MEA)is widely considered to be the most promising type of electrolyzer for the practical application of electrochemical CO_(2) reduction reaction(CO_(2)RR).In MEAs,a square-shaped cross-sec...Membrane electrode assembly(MEA)is widely considered to be the most promising type of electrolyzer for the practical application of electrochemical CO_(2) reduction reaction(CO_(2)RR).In MEAs,a square-shaped cross-section in the flow channel is normally adopted,the configuration optimization of which could potentially enhance the performance of the electrolyzer.This paper describes the numerical simulation study on the impact of the flow-channel cross-section shapes in the MEA electrolyzer for CO_(2)RR.The results show that wide flow channels with low heights are beneficial to the CO_(2)RR by providing a uniform flow field of CO_(2),especially at high current densities.Moreover,the larger the electrolyzer,the more significant the effect is.This study provides a theoretical basis for the design of high-performance MEA electrolyzers for CO_(2)RR.展开更多
Employing multiple metals for synergistic electronic structure regulation emerges as a promising approach to develop highly efficient and robust electrocatalysts for hydrogen evolution at ampere levels.In this study,a...Employing multiple metals for synergistic electronic structure regulation emerges as a promising approach to develop highly efficient and robust electrocatalysts for hydrogen evolution at ampere levels.In this study,a series of Schreibersite-type intermetallic compounds,particularly Mo_(2)Fe_(0.8)Ru_(0.2)P,are synthesized through high-temperature solid-phase synthesis.Experimental results demonstrate that the integration of Ru significantly improves the kinetics of proton adsorption and desorption during the hydrogen evolution reaction(HER).Additionally,density functional theory(DFT)calculations and X-ray absorption near edge structure(XANES)analyses effectively corroborate the pronounced d-orbital hybridization of Fe within the structure,which facilitates the transfer of hydroxide ions and the maintenance of material durability during alkaline HER processes.Remarkably,Mo_(2)Fe_(0.8)Ru_(0.2)P exhibits superior alkaline HER activity,characterized by an overpotential of merely 48 mV at a current density of 10 mA cm^(-2).After prolonged operation of 1000 h at high current densities(1.1 A cm^(-2)),the activity decline remains minimal,under 4%(with overpotential increasing from 258 mV to 268 mV).These results demonstrate the potential of strategically combining metallic elements to design high-performance industrial-grade electrocatalysts.展开更多
CO_(2)reduction reaction(CO_(2)RR)electrolyzers based on gas diffusion electrode(GDE)enable the direct mass transfer of CO_(2)to the catalyst surface for participation in the reaction,thereby establishing an efficient...CO_(2)reduction reaction(CO_(2)RR)electrolyzers based on gas diffusion electrode(GDE)enable the direct mass transfer of CO_(2)to the catalyst surface for participation in the reaction,thereby establishing an efficient three-phase reaction interface that significantly enhances current density.However,current hydrophobic modification methods face difficulties in achieving precise and substantial control over wettability,and the hydrophobic modifiers tend to significantly impair the conductivity of the electrode and ion transport capabilities.This study employs Nafion ionomers to hydrophobically modify the threedimensional catalyst layer,revealing the bifunctionality of Nafion.The fluorinated backbone of Nafion ensures the hydrophobicity of the entire catalyst layer,while its sulfonic acid groups promote ion transport,without significantly affecting the conductivity of the electrode.Furthermore,by employing modifiers with distinct wettability characteristics,a highly efficient and large-scale manipulation of the hydrophilic/hydrophobic properties of the catalyst layer was successfully realized.The electrode,constructed with silver nanopowder as a representative catalyst and modified with the hydrophobic ionomer Nafion,exhibits a substantial enhancement in both catalytic activity and durability.The optimized electrode exhibited exceptional electrocatalytic performance in both flow cell and membrane electrode assembly(MEA)configurations.Notably,in the MEA,the electrode achieved a remarkable CO Faradaic efficiency(FE)of 93.3%at a total current density of 200 mA cm^(-2),while maintaining stable operation for over 62 h.展开更多
Highly oriented pyrolytic graphite (HOPG) is frequently adopted as the reaction target in12C+12C fusion reaction experiments owing to its superior purity.In this study,we investigate the reaction yield dependence on t...Highly oriented pyrolytic graphite (HOPG) is frequently adopted as the reaction target in12C+12C fusion reaction experiments owing to its superior purity.In this study,we investigate the reaction yield dependence on the accumulated beam dose on HOPG target using a novel detection system consisting of a time-projection chamber and silicon array.The reaction yields are significantly reduced under intense beam bombardment owing to radiation damage to the HOPG surface.The α_(0) and p_(0,1) yields decrease by 51.5% and 25%,respectively,when the ^(12)C^(2+) beam dose accumulates at 5 C.Using the novel detection system and HOPG target,the α0yield is determined to be 2.68_(-1.69)^(+4.69)×10^(-17/12) C after correcting for the yield loss due to radiation damage.Our result represents the highest sensitivity achieved to date in direct measurements of ^(12)C(12C,α_(0))^(20)Ne.展开更多
基金supported by Special Funding Projects for Local Science and Technology Development guided by the Central Committee(No.YDZJSX2022C028)the Fundamental Research Program of Shanxi Province(Nos.20210302123218 and 202203021211187)+4 种基金Innovation and Entrepreneurship Training Program for College Students in Shanxi Province(202210109006)the National Natural Science Foundation(52474367)the Key Research and Development for University-Local Government Collaboration of Lvliang City(2024XDHZ01)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(2025Q022)the Foundation of State Key Laboratory of Advanced Metallurgy,USTB(K22-10).
文摘The structural changes in the CaO-SiO_(2)-Al_(2)O_(3)-MgO slag system with varying CaO contents were investigated through molecular dynamics(MD)simulations,and its effect on the dissolution behavior of alumina inclusions was characterized by the Kullback-Leibler(KL)divergence.The slag structure analysis revealed that the[AlO]tetrahedral structure was the primary network structure in the slag.With increasing the CaO content,the non-bridge oxygen(NBO)content in the slag structure increases,and the bridge oxygen(BO)content decreases,thereby reducing the complexity of the slag network structure.Raman spectroscopy detection verifies the results of the MD simulations.The results indicated that the dissolution rate of alumina inclusions accelerates with increasing the CaO content in the slag,owing to the reduced complexity of the slag network structure and the enhanced interatomic interactions.The simulation results for the dissolution of alumina inclusions were consistent with theoretical calculations based on the slag inclusion capacity and the dimensionless dissolution rate of inclusions.Radial distribution function analysis demonstrated that the interaction between atoms in the slag system and alumina inclusions strengthens,increasing the dissolution rate of alumina inclusions.The[AlO_(6)]octahedral structure of the alumina inclusions is disrupted,forming BO structures,which in turn enhances the complexity of the slag network structure,slowing the dissolution rate of alumina inclusions.In contrast,the slag system with a higher CaO content has a relatively simpler network structure,promoting faster alumina inclusion dissolution.
基金jointly supported by the National Natural Science Foundation of China(Grant U2442214)the China Meteorological Administration Youth Innovation Team(Grant No.CMA2024QN10)+1 种基金the National Defense Science and Technology Bureau’s 14th Five-Year Civil Aerospace Preresearch Project(Grant Nos.D030303 and D040204)the International Space Water Cycle Observation Constellation Program(Grant No.183311KYSB20200015).
文摘China launched its first spaceborne Precipitation Measurement Radar(PMR)on the FY-3G satellite in April 2023.To achieve the scientific goal of measuring the three-dimensional precipitation structure,evaluating the quantitative measurement ability of the PMR is critical.China operates more than 250 weather radars over the mainland.Consistency of the spaceborne radar with ground-based radars will enhance precipitation measurement ability,especially over oceans and mountains where observations are sparse.Additionally,the spaceborne radar can be used to evaluate the spatial and temporal homogeneity of the ground-based radar network.This paper focuses on comparing the PMR onboard the FY-3G satellite with S-band China New Generation Weather Radars(CINRADs).A comparison algorithm between the PMR and CINRADs has been developed,incorporating detailed quality control,attenuation correction,data optimization,spatiotemporal matching,non-uniform beam filling constraint,uniformity constraint,and frequency correction.The matched data in typical months of four seasons were selected to carry out the comparison.The data consistency between the PMR and CINRADs was analyzed.The correlation coefficient is 0.87,the deviation is 0.89 dB,and the standard deviation is 2.50 dB,based on 98226 matching samples.The results show the radar reflectivity of the PMR is quite comparable to that of the CINRADs,demonstrating that the PMR data quality is satisfactory and can be used to verify and correct data consistency among multiple ground-based radars.This work also paves the way for data fusion and joint application of satellite and ground radars in the future.
基金supported by the Key Technologies Research and Development Program(2024YFC2909605)Black Soil Project of Shenyang Science and Technology Program(24-216-2-07)Fundamental Research Funds for the Central Universities(NO.N25BSS006).
文摘The pervasive accumulation of plastic waste exacerbates environmental degradation and undermines resource circularity.Selective thermal catalysis emerges as a transformative pathway for valorizing waste plastics into value-added chemicals,yet persistent challenges in catalytic activity and product selectivity demand systematic resolution.This review decodes cutting-edge advances in thermal depolymerization by converging two critical dimensions:atomic-scale active site engineering-where rational design of coordination features and interfacial architectures regulates C-C cleavage energetics and intermediate adsorption-and macromolecular-scale manipulation of polymer transient states-leveraging nanoconfinement effects,chain folding dynamics,and thermal fragmentation to accelerate conversion kinetics.We further highlight breakthroughs in operando char-acterization techniques that resolve time-evolving reaction coordinates across catalytic systems.By establishing multiscale structure-activity relationships linking catalyst configurations to polymer dynamics,this analysis derives design paradigms for next-generation upcycling systems.These principles enable economically viable,industrially scalable plastic valorization while charting a strategic trajectory toward carbon-circular economies.
基金supported by the National Natural Science Foundation of China (NSFC) (Grant No.42205044)Feng Yun Application Pioneering Project (FY-APP) Innovation Center for Feng Yun Meteorological Satellite (FYSIC) Special Project (FY-APP-XC-2023.04)the Wuxi University Research Start-up Fund for Recruited Talent。
文摘Ground-based radar is the primary means by which severe storms are monitored and tracked;however, due to limited coverage, important data is often missed over ocean and mountainous areas. On the other hand, geostationary(GEO)weather satellites provide continuous observations with seamless coverage with advanced imager, despite their limited capability to penetrate clouds. Combining satellite and ground-radar observations could exploit the advantages of both techniques, providing tracking capability close to that of ground radar while maintaining full spatial coverage. This study presents a novel method called Multi-dimensional satellite Observation information for Radar Estimation(MORE) to reconstruct radar composite reflectivity(CREF). Deep learning techniques are important components of MORE for estimating CREF from China's Fengyun-4B(FY-4B) GEO satellite observations. Two models are developed: an infraredonly(IR-Single) model available for all times, and a visible-infrared(VIS+IR) model for daytime applications. These models incorporate multi-dimensional satellite observation information, including temporal, spatial, spectral, and viewing angle information, to enhance the accuracy of radar echo reconstruction. Results demonstrate that the VIS+IR model outperforms the IR-Single model, and both models achieves a root-mean-square error(RMSE) of less than 6 dBZ and a coefficient of determination(R~2) of greater than 0.7. The models effectively reconstruct radar echoes, including strong echoes exceeding 50 dBZ, and show good agreement with precipitation data in radar-blind areas. This study offers a valuable solution for severe weather monitoring and tracking in regions lacking ground-based radar observations, and provides a potential tool for enhanced data assimilation in numerical weather prediction(NWP) models.
基金supported by the National Natural Science Foundation of China(Nos.12027809,12350007)National Key R&D Program of China(Nos.2022YFA1605100,2023YFA1606403,and 2023YFE0101600)+1 种基金New Cornerstone Science Foundation through the XPLORER PRIZEfunding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation program under grant agreement No.679038.
文摘A RadioFrequency Quadrupole(RFQ)cooler-buncher system was developed and implemented in a collinear laser spectroscopy setup.This system converts a continuous ion beam into short bunches while enhancing the beam quality and reducing the energy spread.The functionality of the RFQ cooler buncher was verified through offline tests with stable rubidium and indium beams delivered from a surface ion source and a laser ablation ion source,respectively.Bunched ion beams with a full width at half maximum of approximately 2μs in the time-of-flight spectrum were successfully achieved with a transmission efficiency exceeding 60%.The implementation of the RFQ cooler-buncher system also significantly improved the overall transmission efficiency of the collinear laser spectroscopy setup.
基金supported by the National Natural Science Foundation of China(Grant Nos.42075079 and U2442214).
文摘Precipitable water vapor(PWV)is a key component of the Earth’s climate system,playing a vital role in weather,climate,and hydrological cycling.Passive microwave remote sensing offers a promising approach to measure all-sky PWV,though it remains challenging over land.Building on our previous development of a machine learning algorithm,we have created a global terrestrial PWV dataset using measurements from the MicroWave Radiation Imager(MWRI)aboard three FY-3 satellite series(FY-3B,FY-3C and FY-3D).The dataset spans from 2012 to 2020 at a spatial resolution of 0.25°×0.25°.It was validated against SuomiNet GPS and IGRA2(Integrated Global Radiosonde Archive Version 2)PWV products,achieving root-mean-square errors(RMSEs)of 4.47 and 3.89 mm,respectively,with RMSE values ranging from 2.90 to 5.49 mm across diverse surface conditions.As an all-weather PWV product with high-precision,the MWRI PWV dataset addresses gaps in global passive microwave-based terrestrial PWV observations,offering significant value for atmospheric research,climate modeling,hydrological studies,and beyond.
基金funded by the National Key Research and Development Program of China(Grant No.2023YFB3907500)the National Natural Science Foundation(Grant No.42330602)the“Fengyun Satellite Remote Sensing Product Validation and Verification”Youth Innovation Team of the China Meteorological Administration(Grant No.CMA2023QN12)。
文摘The Global Precipitation Measurement(GPM)dual-frequency precipitation radar(DPR)products(Version 07A)are employed for a rigorous comparative analysis with ground-based operational weather radar(GR)networks.The reflectivity observed by GPM Ku PR is compared quantitatively against GR networks from CINRAD of China and NEXRAD of the United States,and the volume matching method is used for spatial matching.Additionally,a novel frequency correction method for all phases as well as precipitation types is used to correct the GPM Ku PR radar frequency to the GR frequency.A total of 20 GRs(including 10 from CINRAD and 10 from NEXRAD)are included in this comparative analysis.The results indicate that,compared with CINRAD matched data,NEXRAD exhibits larger biases in reflectivity when compared with the frequency-corrected Ku PR.The root-mean-square difference for CINRAD is calculated at 2.38 d B,whereas for NEXRAD it is 3.23 d B.The mean bias of CINRAD matched data is-0.16 d B,while the mean bias of NEXRAD is-2.10 d B.The mean standard deviation of bias for CINRAD is 2.15 d B,while for NEXRAD it is 2.29 d B.This study effectively assesses weather radar data in both the United States and China,which is crucial for improving the overall consistency of global precipitation estimates.
基金supported by the National Key Research and Development Program of China(2021YFE0101300 and 2021YFD1901102)the project supported by the Natural Science Basic Research Plan in Shaanxi Province,China(2023-JC-YB-185)the Ningxia Key Research and Development Program,China(2023BCF01018)。
文摘Long-term mulching has improved crop yields and farmland productivity in semiarid areas,but it has also increased greenhouse gas(GHG)emissions and depleted soil fertility.Biochar application has emerged as a promising solution for addressing these issues.In this study,we investigated the effects of four biochar application rates(no biochar(N)=0 t ha^(-1),low(L)=3 t ha^(-1),medium(M)=6 t ha^(-1),and high(H)=9 t ha^(-1))under film mulching and no mulching conditions over three growing seasons.We assessed the impacts on GHG emissions,soil organic carbon sequestration(SOCS),and maize yield to evaluate the productivity and sustainability of farmland ecosystems.Our results demonstrated that mulching increased maize yield(18.68-41.80%),total fixed C in straw(23.64%),grain(28.87%),and root(46.31%)biomass,and GHG emissions(CO_(2),10.78%;N_(2)O,3.41%),while reducing SOCS(6.57%)and GHG intensity(GHGI;13.61%).Under mulching,biochar application significantly increased maize yield(10.20%),total fixed C in straw(17.97%),grain(17.69%)and root(16.75%)biomass,and SOCS(4.78%).Moreover,it reduced the GHG emissions(CO_(2),3.09%;N_(2)O,6.36%)and GHGI(12.28%).These effects correlated with the biochar addition rate,with the optimal rate being 9.0 t ha^(-1).In conclusion,biochar application reduces CO_(2) and N_(2)O emissions,enhances CH_(4) absorption,and improves maize yield under film mulching.It also improves the soil carbon fixation capacity while mitigating the warming potential,making it a promising sustainable management method for mulched farmland in semiarid areas.
基金supported by the National Natural Science Foundation of China(Nos.82171552 and 82170479)the Natural Science Foundation of Shanghai Ctiy(No.21ZR1457500)the Science and Technology Bureau of Shanghai Putuo District(No.ptkwws202102).
文摘Magnolol,a compound extracted from Magnolia officinalis,demonstrates potential efficacy in addressing metabolic dysfunction and cardiovascular diseases.Its biological activities encompass anti-inflammatory,antioxidant,anticoagulant,and anti-diabetic effects.Growth/differentiation factor-15(GDF-15),a member of the transforming growth factorβsuperfamily,is considered a potential therapeutic target for metabolic disorders.This study investigated the impact of magnolol on GDF-15 production and its underlying mechanism.The research examined the pharmacological effect of magnolol on GDF-15 expression in vitro and in vivo,and determined the involvement of endoplasmic reticulum(ER)stress signaling in this process.Luciferase reporter assays,chromatin immunoprecipitation,and in vitro DNA binding assays were employed to examine the regulation of GDF-15 by activating transcription factor 4(ATF4),CCAAT enhancer binding proteinγ(CEBPG),and CCCTC-binding factor(CTCF).The study also investigated the effect of magnolol and ATF4 on the activity of a putative enhancer located in the intron of the GDF-15 gene,as well as the influence of single nucleotide polymorphisms(SNPs)on magnolol and ATF4-induced transcription activity.Results demonstrated that magnolol triggers GDF-15 production in endothelial cells(ECs),hepatoma cell line G2(HepG2)and hepatoma cell line 3B(Hep3B)cell lines,and primary mouse hepatocytes.The cooperative binding of ATF4 and CEBPG upstream of the GDF-15 gene or the E1944285 enhancer located in the intron led to full-power transcription of the GDF-15 gene.SNP alleles were found to impact the magnolol and ATF4-induced transcription activity of GDF-15.In high-fat diet ApoE^(-/-)mice,administration of magnolol induced GDF-15 production and partially suppressed appetite through GDF-15.These findings suggest that magnolol regulates GDF-15 expression through priming of promoter and enhancer activity,indicating its potential as a drug for the treatment of metabolic disorders.
基金supported by grants from the Beijing Municipal Public Welfare Development and Reform Pilot Project for Medical Research Institutes(PWD&RPP-MRI,JYY2023-6)the R&D Program of Beijing Municipal Education Commission(KZ20231002543).
文摘Background:Dry eye disease(DED)predominantly results from elevated tear film os-molarity,which can not only cause ocular inconvenience but may lead to visual impair-ments,severely compromising patient well-being and exerting substantial economic burdens as well.Astaxanthin(AST),a member of the xanthophylls and recognized for its robust abilities to combat inflammation and oxidation,is a common dietary sup-plement.Nonetheless,the precise molecular pathways through which AST influences DED are still poorly understood.Methods:Therapeutic targets for AST were identified using data from the GeneCards,PharmMapper,and Swiss Target Prediction databases,and STITCH datasets.Similarly,targets for dry eye disease(DED)were delineated leveraging resources such as the Therapeutic Target Database(TTD),DisGeNET,GeneCards,and OMIM databases,and DrugBank datasets.Interactions among shared targets were charted and dis-played using CytoScape 3.9.0.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were conducted to elucidate the functions of pivotal tar-gets within the protein-protein interaction network.Molecular interactions between AST and key targets were confirmed through molecular docking using AutoDock and PyMOL.Molecular dynamics simulations were performed using GROMACS 2022.3.Viability of human corneal epithelial cells(hCEC)was assessed across varying concen-trations of AST.A mouse model of experimental DED was developed using 0.1%ben-zalkonium chloride(BAC),and the animals were administered 100 mg/kg/day of AST orally for 7 days.The efficacy of the treatments was assessed through a series of di-agnostic tests to evaluate the condition of the ocular surface after the interventions.The levels of inflammation and oxidative stress were quantitatively assessed using methods such as reverse transcription-polymerase chain reaction(RT-PCR),Western blot,and immunofluorescence staining.Results:Network pharmacology suggests that AST may alleviate DED by influenc-ing oxidation-reduction signaling pathways and reducing oxidative stress provoked by BAC.In vivo experiments demonstrated an improved overall condition in AST-administered mice in contrast to the control group.Immunofluorescence staining analyses indicated a decrease in Keap1 protein in the corneal tissues of AST-treated mice and a significant increase in Nrf2 and HO-1 protein.In vitro studies demon-strated that AST significantly enhanced cell viability and suppressed reactive oxy-gen species expression under hyperosmotic(HS)conditions,thereby protecting the human corneal epithelium.Conclusion:AST is capable of shielding mice from BAC-induced DED,decelerating the progression of DED,and mitigating oxidative stress damage under HS conditions in hCEC cells.The protective impact of AST on DED may operate through stimulating the Keap1-Nrf2/HO-1 signaling pathway.Our research findings indicate that AST may be a promising treatment for DED,offering new insights into DED treatment.
基金financially supported by the National Key Research and Development Program of China(No.2022YFB3705200)the National Natural Science Foundation of China(NSFC)(Nos.52321001,52130002 and 52371123)the IMR Innovation Fund(No.2024-PY07).
文摘With the increasing demand for high-performance metallic materials,the improvement of fatigue strength(FS)has become a crucial issue.This study focuses on the AISI 52100 steel,a material with leading fatigue performance and low-cost raw material,aiming to further improve its FS.It is found that the fatigue damage mechanism of 52100 steels with different tensile strengths has undergone significant changes,and the inclusions,mainly nitride and oxide,are key factors limiting the further improvement of FS.Therefore,the size reduction and modification of inclusions were attempted through the rare earth addition and strict control of harmful elements.Combining targeted microstructure adjustment,the FS of the 52100 steel has been further enhanced to~1.6 GPa,exceeding that of other metallic materials(performed in uniaxial tension with a stress ratio of R=0.1),and thus establishing it as a standout for its exceptional performance-to-cost ratio.By clarifying the influences of different types of inclusions on fatigue performance and establishing the correlation between micro-hardness(or strength)and FS,an optimization strategy for FS improvement of the 52100 steel was proposed.The FS has been improved by approximately 187 MPa at most by implementing this strategy.These achievements provide feasible technical approaches and theoretical foundations for the anti-fatigue design of metallic materials.
文摘We have developed a novel S-scheme heterojunction photocatalyst for the photocatalytic production of hydrogen peroxide(H_(2)O_(2))via a two-electron(2e^(-))oxygen reduction reaction.This S-scheme heterojunction Tph-Dha-COF@Nb_(2)C was fabricated via the in-situ solvothermal growth of Tph-Dha-COF nanostructures on amino-functionalized Nb_(2)C MXene nanoflakes(Nb_(2)C-NH_(2)).The integration of Nb_(2)C significantly extended the visible light absorption of Tph-Dha-COF into the near-infrared region for photocatalytic H_(2)O_(2) production.The Tph-Dha-COF@Nb_(2)C composite demonstrated efficient charge separation,rapid electron transfer,and enhanced oxygen adsorption.Consequently,the Tph-Dha-COF@Nb_(2)C heterojunction exhibited a high H_(2)O_(2) production rate of 1833μmol g^(-1) h^(-1) without sacrificial agents.In-situ Fourier transformed infrared spectroscopy and density functional theory calculations revealed the photocatalytic H_(2)O_(2) production mechanism.The generated H_(2)O_(2) demonstrated enhanced antibacterial activity.This work presents the first application of Nb_(2)C in the photocatalytic synthesis of H_(2)O_(2) and provides a novel strategy for constructing COF-based heterojunctions for photocatalytic H_(2)O_(2) generation and wastewater treatment.
基金the National Key R&D Program of China(No.2021YFA1501503)the National Natural Science Foundation of China(Nos.22250008,22121004,22108197)+3 种基金the Haihe Laboratory of Sustainable Chemical Transformations(No.CYZC202107)the Natural Science Foundation of Tianjin City(No.21JCZXJC00060)the Program of Introducing Talents of Discipline to Universities(No.BP0618007)the Xplorer Prize for financial support。
文摘Membrane electrode assembly(MEA)is widely considered to be the most promising type of electrolyzer for the practical application of electrochemical CO_(2) reduction reaction(CO_(2)RR).In MEAs,a square-shaped cross-section in the flow channel is normally adopted,the configuration optimization of which could potentially enhance the performance of the electrolyzer.This paper describes the numerical simulation study on the impact of the flow-channel cross-section shapes in the MEA electrolyzer for CO_(2)RR.The results show that wide flow channels with low heights are beneficial to the CO_(2)RR by providing a uniform flow field of CO_(2),especially at high current densities.Moreover,the larger the electrolyzer,the more significant the effect is.This study provides a theoretical basis for the design of high-performance MEA electrolyzers for CO_(2)RR.
基金supported by Research Grants of the NRF(2023R1A2C2003823,RS-2024-00405818)funded by the National Research Foundation under the Ministry of Science,ICT&Future,Korea。
文摘Employing multiple metals for synergistic electronic structure regulation emerges as a promising approach to develop highly efficient and robust electrocatalysts for hydrogen evolution at ampere levels.In this study,a series of Schreibersite-type intermetallic compounds,particularly Mo_(2)Fe_(0.8)Ru_(0.2)P,are synthesized through high-temperature solid-phase synthesis.Experimental results demonstrate that the integration of Ru significantly improves the kinetics of proton adsorption and desorption during the hydrogen evolution reaction(HER).Additionally,density functional theory(DFT)calculations and X-ray absorption near edge structure(XANES)analyses effectively corroborate the pronounced d-orbital hybridization of Fe within the structure,which facilitates the transfer of hydroxide ions and the maintenance of material durability during alkaline HER processes.Remarkably,Mo_(2)Fe_(0.8)Ru_(0.2)P exhibits superior alkaline HER activity,characterized by an overpotential of merely 48 mV at a current density of 10 mA cm^(-2).After prolonged operation of 1000 h at high current densities(1.1 A cm^(-2)),the activity decline remains minimal,under 4%(with overpotential increasing from 258 mV to 268 mV).These results demonstrate the potential of strategically combining metallic elements to design high-performance industrial-grade electrocatalysts.
基金National Key R&D Program of China(2023YFA1507902,2021YFA1500804)the National Natural Science Foundation of China(22121004,22038009,22250008)+2 种基金the Haihe Laboratory of Sustainable Chemical Transformations(CYZC202107)the Program of Introducing Talents of Discipline to Universities,China(No.BP0618007)the Xplorer Prize,China,for their financial support。
文摘CO_(2)reduction reaction(CO_(2)RR)electrolyzers based on gas diffusion electrode(GDE)enable the direct mass transfer of CO_(2)to the catalyst surface for participation in the reaction,thereby establishing an efficient three-phase reaction interface that significantly enhances current density.However,current hydrophobic modification methods face difficulties in achieving precise and substantial control over wettability,and the hydrophobic modifiers tend to significantly impair the conductivity of the electrode and ion transport capabilities.This study employs Nafion ionomers to hydrophobically modify the threedimensional catalyst layer,revealing the bifunctionality of Nafion.The fluorinated backbone of Nafion ensures the hydrophobicity of the entire catalyst layer,while its sulfonic acid groups promote ion transport,without significantly affecting the conductivity of the electrode.Furthermore,by employing modifiers with distinct wettability characteristics,a highly efficient and large-scale manipulation of the hydrophilic/hydrophobic properties of the catalyst layer was successfully realized.The electrode,constructed with silver nanopowder as a representative catalyst and modified with the hydrophobic ionomer Nafion,exhibits a substantial enhancement in both catalytic activity and durability.The optimized electrode exhibited exceptional electrocatalytic performance in both flow cell and membrane electrode assembly(MEA)configurations.Notably,in the MEA,the electrode achieved a remarkable CO Faradaic efficiency(FE)of 93.3%at a total current density of 200 mA cm^(-2),while maintaining stable operation for over 62 h.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB34020200)National Key Research and Development Program(MOST 2022YFA1602304)+1 种基金Scientific Research Instrument and Equipment Development Program of the Chinese Academy of Sciences(No.GJJSTD20210007)National Natural Science Foundation of China(Nos.12175156,U1632142).
文摘Highly oriented pyrolytic graphite (HOPG) is frequently adopted as the reaction target in12C+12C fusion reaction experiments owing to its superior purity.In this study,we investigate the reaction yield dependence on the accumulated beam dose on HOPG target using a novel detection system consisting of a time-projection chamber and silicon array.The reaction yields are significantly reduced under intense beam bombardment owing to radiation damage to the HOPG surface.The α_(0) and p_(0,1) yields decrease by 51.5% and 25%,respectively,when the ^(12)C^(2+) beam dose accumulates at 5 C.Using the novel detection system and HOPG target,the α0yield is determined to be 2.68_(-1.69)^(+4.69)×10^(-17/12) C after correcting for the yield loss due to radiation damage.Our result represents the highest sensitivity achieved to date in direct measurements of ^(12)C(12C,α_(0))^(20)Ne.
