The nonuniform microstructure of magnesium alloy rolled sheets tends to influence their plastic deformation capacity.This study employed multi-pass restricted rolling to successfully prepare AZ31 magnesium alloy rolle...The nonuniform microstructure of magnesium alloy rolled sheets tends to influence their plastic deformation capacity.This study employed multi-pass restricted rolling to successfully prepare AZ31 magnesium alloy rolled sheets with a uniform microstructure,enhancing their mechanical properties.Quasi-in-situ tensile EBSD was used to investigate the effect of microstructure uniformity on the plastic deformation and fracture behavior of magnesium alloy.The results demonstrate that the nonuniformity of the magnesium alloy microstructure intensifies the strain asynchrony between adjacent grains,leading to relative misalignment and crack formation.Fine grains cannot coordinate the strain within their adjacent coarse grains,resulting in ledge formation at their common grain boundaries.Moreover,low-angle grain boundaries(LAGB)influence fracture behavior,rendering fine grains penetrated by LAGB more susceptible to becoming strain concentration areas that promote intergranular fracture and even transgranular fracture.展开更多
Microorganisms can colonize the surface of microplastics(MPs)to form a distinctive microbiome,known as a“plastisphere”which is regarded as an anthropogenic niche for microbial growth.However,bacterial community asse...Microorganisms can colonize the surface of microplastics(MPs)to form a distinctive microbiome,known as a“plastisphere”which is regarded as an anthropogenic niche for microbial growth.However,bacterial community assembly in virgin and aging MP plastispheres across different habitats is poorly understood.This study aims to assess the variations in bacterial community assembly across different niches and habitats with an in situ ex-periment,in which constructed forest wetland(FW),natural lake wetland(LW),and lotus pond wetland(LP)were habitats,and plastispheres of virgin and aging low-density polyethylene(LDPE)MPs,as well as surround-ing wetland soils were niches.Significant niche-related differences in bacterial communities were observed,with lower diversity and enrichment of potential plastic-degrading bacteria in the plastisphere than in the soil bacterial communities.Furthermore,habitat-related differences exerted a more pronounced influence on the beta-diversity patterns of the bacterial communities.The linear regression analyses indicated that the local species pool con-tributed more to bacterial community assembly in the LW wetland,whereas the relative abundance of species was the primary factor in the LP wetland.The null model analysis indicated that plastisphere bacterial communi-ties were predominantly driven by the stochastic process,with a more deterministic assembly observed in the LP wetland and soil bacterial communities.Additionally,the primary ecological process shaping plastisphere com-munities shifted from drift in the virgin LDPE to homogenising dispersal in the aging LDPE.This study provides new insights into the fate and ecological impacts of MPs in wetlands,thereby facilitating the effective regulations of plastic pollution.展开更多
Electrolytes play a key role in determining the electrochemical performance,safety,and lifespan of potassium-based batteries,making their selection and optimization a critical area of research.This study systematicall...Electrolytes play a key role in determining the electrochemical performance,safety,and lifespan of potassium-based batteries,making their selection and optimization a critical area of research.This study systematically investigates the effects of two major potassium-based battery electrolytes,potassium hexafluorophosphate(KPF_(6))and potassium difluorosulfonimide(KFSI)in ethylene carbonate/diethyl carbonate(EC/DEC)solvents,on battery performance,solid electrolyte interphase(SEI)stability,aluminum(Al)current collector corrosion behavior,electrochemical stability window,and dendrite growth issue.Experimental results reveal that KFSI electrolyte significantly outperforms KPF_(6)in terms of cycling stability,rate capability,and Coulombic efficiency(CE),primarily due to the formation of a high-quality SEI on electrode surface.Through X-ray photoelectron spectroscopy(XPS)and time-of-flight secondary ion mass spectrometry(TOF-SIMS)analyses,we construct the SEI structure for both electrolytes,and find that the SEI formed by KFSI is more uniform and stable.Additionally,KPF_(6)exhibits weaker corrosivity towards the Al current collector compared to KFSI due to the formation of an AlF_(3) layer with higher oxidation stability on Al surface.Furthermore,in-situ optical microscopy observations indicate that the dendrite growth in KFSI electrolyte is more uniform,preventing the aggregates.These findings provide essential experimental evidence and theoretical support for optimizing the electrolyte in potassium-based batteries.展开更多
The pollen intine plays important roles in pollen germination and tube growth,but related information in Ginkgo biloba remains unclear.We isolated and obtained de-exined pollen from G.biloba.Using fluorescent probes,w...The pollen intine plays important roles in pollen germination and tube growth,but related information in Ginkgo biloba remains unclear.We isolated and obtained de-exined pollen from G.biloba.Using fluorescent probes,we observed the strongest cellulose fluorescence in the pollen intine.De-esterified pectin immunolabeled with JIM5 was present throughout the entire cell wall,whereas esterified pectin recognized by the monoclonal antibody JIM7 was concentrated in some regions.Callose staining with aniline blue was observed across the entire surface of the pollen intine.These results were confirmed by Fourier Transform InfraRed(FTIR)analysis.We also used proteomic approaches to identify different proteins between mature and de-exined pollen(48h after hydration)in vitro.Based on mass spectrometry,de-exined pollen had more proteins than mature pollen,including calmodulin,serine hydroxymethyltransferase,β-galactosidase 6,and class IV chitinase.According to Gene Ontology(GO)analysis,the differentially expressed proteins were mainly associated with transportation,defense reaction,sugar metabolism,energy metabolism,signal transduction,and cell wall formation.These findings suggest that most proteins involved in pollen germination and pollen tube growth are synthesized during pollen hydration,indicating the important role of pollen hydration in the reproductive process of G.Biloba.展开更多
Lettuce is an important leafy vegetable that represents a significant dietary source of antioxidants and bioactive compounds.However,the levels of metabolites in different lettuce cultivars are poorly characterized.In...Lettuce is an important leafy vegetable that represents a significant dietary source of antioxidants and bioactive compounds.However,the levels of metabolites in different lettuce cultivars are poorly characterized.In this study,we used combined GC×GC-TOF/MS and UPLC-IMS-QTOF/MS to detect and relatively quantify metabolites in 30 lettuce cultivars representing large genetic diversity.Comparison with online databases,the published literature,standards as well using collision cross-section values enabled putative identification of 171 metabolites.Sixteen of these 171 metabolites(including phenolic acid derivatives,glycosylated flavonoids,and one iridoid)were present at significantly different levels in leaf and head type lettuces,which suggested the significant metabolomic variations between the leaf and head types of lettuce are related to secondary metabolism.A combination of the results and metabolic network analysis techniques suggested that leaf and head type lettuces contain not only different levels of metabolites but also have significant variations in the corresponding associated metabolic networks.The novel lettuce metabolite library and novel non-targeted metabolomics strategy devised in this study could be used to further characterize metabolic variations between lettuce cultivars or other plants.Moreover,the findings of this study provide important insight into metabolic adaptations due to natural and human selection,which could stimulate further research to potentially improve lettuce quality,yield,and nutritional value.展开更多
Chemical immobilization is one of the most effective technologies for remediating sites with heavy metals,but the selection of proper immobilization material and determination of its dose ratio is a challenge that lim...Chemical immobilization is one of the most effective technologies for remediating sites with heavy metals,but the selection of proper immobilization material and determination of its dose ratio is a challenge that limits the remediation efficiency.In this study,we conducted a meta-analysis of 489 independent observations on the immobilization of heavy metals,in which the immobilization materials were divided into biochar,phosphate,lime,metal oxides,and clay minerals.The statistical analysis of these observations revealed that the material dose ratio was the most important parameter that controlled immobilization efficiency,and the Freundlich adsorption model was successfully applied to calculate the bioavailable heavy metal(BHM)concentration after immobilization.Based on the calculation results,phosphate was the most effective material for Pb immobilization.Lime was the most effective when the initial bioavailable Cd content was 0.1–1 mg kg^(-1),whereas the immobilization effects of lime and phosphate were similar when the initial bioavailable Cd content was 10 mg kg^(-1).In addition to the material dose ratio,initial soil pH(pHi)and organic matter(OM)content were negatively correlated,whereas the fraction of initial BHMs before immobilization(FB)and immobilization time were positively correlated with immobilization efficiency.A numerical model that considered the material dose ratio,pHi,OM,FB,and immobilization time was established to calculate the residual BHM concentration after immobilization.However,these factors only explained less than 45%of the immobilization effect,indicating that other factors,such as the sub-type of the material and modification methods,also affect the immobilization effect.These results could help to optimize the type of immobilization material of heavy metals and its dose ratio in practical engineering applications.展开更多
The stable sub-angstrom resolution of the aberration-corrected scanning transmission electron microscope(ACSTEM)makes it an advanced and practical characterization technique for all materials.Owing to the prosperous a...The stable sub-angstrom resolution of the aberration-corrected scanning transmission electron microscope(ACSTEM)makes it an advanced and practical characterization technique for all materials.Owing to the prosperous advancement in computational technology,specialized software and programs have emerged as potent facilitators across the entirety of electron microscopy characterization process.Utilizing advanced image processing algorithms promotes the rectification of image distortions,concurrently elevating the overall image quality to superior standards.Extracting high-resolution,pixel-level discrete information and converting it into atomic-scale,followed by performing statistical calculations on the physical matters of interest through quantitative analysis,represent an effective strategy to maximize the value of electron microscope images.The efficacious utilization of quantitative analysis of electron microscope images has become a progressively prominent consideration for materials scientists and electron microscopy researchers.This article offers a concise overview of the pivotal procedures in quantitative analysis and summarizes the computational methodologies involved from three perspectives:contrast,lattice and strain,as well as atomic displacements and polarization.It further elaborates on practical applications of these methods in electronic functional materials,notably in piezoelectrics/ferroelectrics and thermoelectrics.It emphasizes the indispensable role of quantitative analysis in fundamental theoretical research,elucidating the structure–property correlations in high-performance systems,and guiding synthesis strategies.展开更多
Solid oxide cells(SOCs)are emerging devices for efficient energy storage and conversion.However,during SOC operation,gaseous chromium(Cr)species released from Fe-Cr alloy interconnect can lead to Cr deposition and poi...Solid oxide cells(SOCs)are emerging devices for efficient energy storage and conversion.However,during SOC operation,gaseous chromium(Cr)species released from Fe-Cr alloy interconnect can lead to Cr deposition and poisoning of air electrodes,causing substantial degradation in electrochemical performance and compromising the longterm stability of SOCs.This mini-review examines the mechanism of Cr deposition and poisoning in air electrodes under both fuel-cell and electrolysis modes.Furthermore,emphasis is placed on the recent advancements in strategies to mitigate Cr poisoning,offering insights into the rational design and development of active and Cr-tolerant air electrodes for SOCs.展开更多
Fifty agricultural soil samples collected from Fuzhou,southeast China,were first investigated for the occurrence,distribution,and potential risks of twelve organophosphate esters(OPEs).The total concentration of OPEs(...Fifty agricultural soil samples collected from Fuzhou,southeast China,were first investigated for the occurrence,distribution,and potential risks of twelve organophosphate esters(OPEs).The total concentration of OPEs(ΣOPEs)in soil ranged from 1.33 to 96.5 ng/g dry weight(dw),with an average value of 17.1 ng/g dw.Especially,halogenated-OPEs were the predominant group with amean level of 9.75 ng/g dw,and tris(1-chloro-2-propyl)phosphate(TCIPP)was the most abundant OPEs,accounting for 51.1%ofΣOPEs.The concentrations of TCIPP andΣOPEs were found to be significantly higher(P<0.05)in soils of urban areas than those in suburban areas.In addition,the use of agricultural plastic films and total organic carbon had a positive effect on the occurrence of OPE in this study.The positive matrix factorization model suggested complex sources of OPEs in agricultural soils from Fuzhou.The ecological risk assessment demonstrated that tricresyl phosphate presented a medium risk to land-based organisms(0.1≤risk quotient<1.0).Nevertheless,the carcinogenic and noncarcinogenic risks for human exposure to OPEs through soil ingestion and dermal absorption were negligible.These findings would facilitate further investigations into the pollution management and risk control of OPEs.展开更多
Liposomes serve as critical carriers for drugs and vaccines,with their biological effects influenced by their size.The microfluidic method,renowned for its precise control,reproducibility,and scalability,has been wide...Liposomes serve as critical carriers for drugs and vaccines,with their biological effects influenced by their size.The microfluidic method,renowned for its precise control,reproducibility,and scalability,has been widely employed for liposome preparation.Although some studies have explored factors affecting liposomal size in microfluidic processes,most focus on small-sized liposomes,predominantly through experimental data analysis.However,the production of larger liposomes,which are equally significant,remains underexplored.In this work,we thoroughly investigate multiple variables influencing liposome size during microfluidic preparation and develop a machine learning(ML)model capable of accurately predicting liposomal size.Experimental validation was conducted using a staggered herringbone micromixer(SHM)chip.Our findings reveal that most investigated variables significantly influence liposomal size,often interrelating in complex ways.We evaluated the predictive performance of several widely-used ML algorithms,including ensemble methods,through cross-validation(CV)for both lipo-some size and polydispersity index(PDI).A standalone dataset was experimentally validated to assess the accuracy of the ML predictions,with results indicating that ensemble algorithms provided the most reliable predictions.Specifically,gradient boosting was selected for size prediction,while random forest was employed for PDI prediction.We successfully produced uniform large(600 nm)and small(100 nm)liposomes using the optimised experimental conditions derived from the ML models.In conclusion,this study presents a robust methodology that enables precise control over liposome size distribution,of-fering valuable insights for medicinal research applications.展开更多
The morphology and dimension of W phases play an important role in determining mechanical properties of Mg-RE-Zn(where RE denotes rare earth elements)alloys.In this study,theγ′platelet and W particle occurred in the...The morphology and dimension of W phases play an important role in determining mechanical properties of Mg-RE-Zn(where RE denotes rare earth elements)alloys.In this study,theγ′platelet and W particle occurred in the aged Mg-2Dy-0.5Zn(at.%)alloys were investigated by aberration-corrected scanning transmission electron microscopy.A novel formation mechanism of W phase was proposed,and its effects on the morphology and dimension of W particle,as well as mechanical properties of Mg-2Dy-0.5Zn alloys,were also discussed particularly.Different from other Mg-RE-Zn alloys,the nucleation and growth of W particle in Mg-Dy-Zn alloys mainly depend on the precipitatedγ′platelet.Primarily,a mass of Dy and Zn solute atoms concentrated nearγ′platelet or between two adjacentγ′platelets can meet the composition requirement of W particle nucleation.Next,the smaller interfacial mismatch between W andγ′facilitates the nucleation and growth of W particle.Thirdly,the growth of W particle can be achieved by consuming the surroundingγ′platelets.The nucleation and growth mechanisms make W particles exhibit rectangular or leaf-like and remain at the nanoscale.The coexistence ofγ′platelets and nanoscale W particles,and some better interfacial relationships between phases,lead to a high strength-ductility synergy of alloy.The findings may provide some fundamental guidelines for the microstructure design and optimization of new-type Mg-based alloys.展开更多
With the rapid development of electric vehicles,hybrid electric vehicles and smart grids,people's demand for large-scale energy storage devices is increasingly intense.As a new type of secondary battery,potassium ...With the rapid development of electric vehicles,hybrid electric vehicles and smart grids,people's demand for large-scale energy storage devices is increasingly intense.As a new type of secondary battery,potassium ion battery is promising to replace the lithium-ion battery in the field of large-scale energy storage by virtue of its low price and environmental friendliness.At present,the research on the anode materials of potassium ion batteries mainly focuses on carbon materials and the design of various nanostructured metal-based materials.Problems such as poor rate performance and inferior cycle life caused by electrode structure comminution during charge and discharge have not been solved.Quantum dots/nanodots materials are a new type of nanomaterials that can effectively improve the utilization of electrode materials and reduce production costs.In addition,quantum dots/nanodots materials can enhance the electrode reaction kinetics,reduce the stress generated in cycling,and effectively alleviate the agglomeration and crushing of electrode materials.In this review,we will systematically introduce the synthesis methods,K+storage properties and K+storage mechanisms of carbon quantum dots and carbon-based transition metal compound quantum dots composites.This review will have significant references for potassium ion battery researchers.展开更多
Ferroptosis is a novel form of cell death driven by oxidative damage,and is implicated in various pathological conditions,including neurodegenerative diseases,retinal damage,and ischemia-reperfusion injury of organs.I...Ferroptosis is a novel form of cell death driven by oxidative damage,and is implicated in various pathological conditions,including neurodegenerative diseases,retinal damage,and ischemia-reperfusion injury of organs.Inhibiting ferroptosis has shown great promise as a therapeutic strategy for these diseases,underscoring the urgent need to develop effective ferroptosis inhibitors.Although Ferrostatin-1(Fer-1)is a potent ferroptosis inhibitor,its susceptibility to oxidation and metabolic inactivation limits its clinical utility.In this study,the accumulation of peroxides and the resulting oxidative damage in the cellular microenvironment during ferroptosis were utilized to design Ferrostatin-1 prodrugs with reactive oxygen species-responsive features.This approach led to the development of a series of ferroptosis inhibitors that were capable of recognizing oxidative damage in diseased areas,allowing for targeted release and improved stability.The novel compounds demonstrated significant inhibitory effects and selectivity against RSL-3-induced ferroptosis in HK-2 cells,with compound a1 exhibiting an EC50 of 15.4�0.7μM,outperforming Fer-1.These compounds effectively identify the oxidative microenvironment associated with ferroptosis,enabling the targeted release of Fer-1,which prevents lipid peroxide accumulation and inhibits ferroptosis.This strategy holds promise for treating diseases related to ferroptosis,offering a targeted and intelligent therapeutic approach.展开更多
Impact of texture type on the magnetic properties of ultrahigh density perpendicular magnetic recording media L1_(0)-FePt thin film was investigated,so were the texture formation and evolution mechanism.Reuss,Voigt,an...Impact of texture type on the magnetic properties of ultrahigh density perpendicular magnetic recording media L1_(0)-FePt thin film was investigated,so were the texture formation and evolution mechanism.Reuss,Voigt,and Hill models were used to determine the anisotropic elastic modulus of L1_(0)-FePt thin film with fiber texture.Then,the elastic strain energies of thin films under various stress conditions were calculated.Results reveal that the stress condition has a significant influence on the fiber texture evolution.When the L1_(0)-FePt thin film is subjected to compressive in-plane strain prior to ordering phase transformation,the formation of{100}fiber texture is promoted.On the contrary,the ordering phase transformation under tensile in-plane strain promotes the{001}fiber texture formation.展开更多
To modify the stable thermodynamics and poor kinetics of magnesium hydride(MgH_(2))for solid-state hydrogen storage,MIL-100(Fe)was in situ fabricated on the surfaces of TiO_(2)nano-sheets(NS)by a self-assembly method,...To modify the stable thermodynamics and poor kinetics of magnesium hydride(MgH_(2))for solid-state hydrogen storage,MIL-100(Fe)was in situ fabricated on the surfaces of TiO_(2)nano-sheets(NS)by a self-assembly method,and the prepared TiO_(2)NS@MIL-100(Fe)presents an excellent catalytic effect on MgH_(2).The MgH_(2)+7wt.%TiO_(2)NS@MIL-100(Fe)composite can release hydrogen at 200℃,achieving a decrease of 150℃ compared to pure MgH_(2).Besides,the activation energy of dehydrogenation is decreased to 70.62 kJ/mol and 4 wt.%H_(2) can be desorbed within 20 min at a low temperature of 235℃.Under conditions of 100℃ and 3 MPa,MgH_(2)+7wt.%TiO_(2)NS@MIL-100(Fe)absorbs 5 wt.%of H_(2) in 10 min.Surprisingly,6.62 wt.%reversible capacity is maintained after 50 cycles.The modification mechanism is confirmed that the presence of oxygen vacancies and the synergistic effect of multivalent titanium in TiO_(2)NS@MIL-100(Fe)greatly enhance the kinetic and thermodynamic properties of MgH_(2).展开更多
Presetting tensile twins(TTs)can enhance the mechanical properties of magnesium(Mg)alloys.Two as-received(AR)sheets,as-received state-A(AR-A)with fiber texture and nonuniform grains and as-received state-B with basal ...Presetting tensile twins(TTs)can enhance the mechanical properties of magnesium(Mg)alloys.Two as-received(AR)sheets,as-received state-A(AR-A)with fiber texture and nonuniform grains and as-received state-B with basal texture and uniform equiaxial grains are selected to induce TTs via a novel method called corrugated wide limit alignment(CWLA),and the corresponding CWLA-processed sheets are denoted as CWLA-processed state-A(C-A)and CWLA-processed state-B(C-B).The results demonstrate that a larger initial average grain size correlates with a higher fraction of TTs induced in Mg sheets,thereby refining the grains and forming a new rolling direction(RD)tilted texture during CWLA.The ultimate tensile strength increases by 32%from AR-A to C-A,primarily due to refinement strengthening and twinning-induced strain hardening.The recrystallization mechanism of C-A is dominated by twinning-induced dynamic recrystallization(DRX),where DRX grains prefer to inherit the orientation of TTs,resulting in an enhanced RD-tilted texture and the formation of multi-modal texture.The recrystallization mechanism of C-B is mainly discontinuous DRX and continuous DRX,and the DRX grains prefer to inherit the orientation of matrix grains,ultimately forming a basal texture.In summary,the tensile mechanical behavior of pre-twinned Mg sheets significantly depends on the grain size and texture of the AR sheets,so they present similar changing trends during tensile deformation.展开更多
Introducing vacancies and constructing S-scheme heterojunctions are promising approaches for enhancing photocatalytic activity.However,the application of this synergistic strategy to realize inexpensive and efficient ...Introducing vacancies and constructing S-scheme heterojunctions are promising approaches for enhancing photocatalytic activity.However,the application of this synergistic strategy to realize inexpensive and efficient photocatalysts remains challenging.In this study,a straightforward hydrothermal and calcination modification strategy was used to prepare a photocatalyst in which abundant nitrogen-oxygen vacancies were coupled with a Ce-ZnO@C-g-C_(3)N_(4)composite with an S-scheme heterojunction.Under sunlight irradiation,the prepared composite achieves 98.3%and 86.4%degradation of methylene blue and ciprofloxacin,with degradation rate constants of 0.3464 and 0.0893 min^(-1),respectively.Compared with ZnO and g-C_(3)N_(4),the degradation rates of methylene blue over the composite catalyst are 34.8 and 22.7 times higher,respectively,and those of ciprofloxacin are 2.4 and 4.9 times higher,respectively.Based on a detailed examination of the catalyst structure and photoelectric properties,the high photocatalytic efficiency is attributed to nitrogen-oxygen vacancies,an enhanced surface area,and synergistic S-scheme heterojunction effects.These factors broaden the spectral range,increase the number of active sites,and facilitate efficient charge transfer,thereby enhancing the photocatalytic reaction.This system demonstrates the feasibility of integrating doping and heterojunction formation to enhance photocatalytic performance synergistically.展开更多
Photosynthesis of hydrogen peroxide(H_(2)O_(2))from H_(2)O and O_(2)is considered to be a promising approach.However,limited to the rapid recombination of photo-generated carriers and sluggish kinetics of O_(2)re-duct...Photosynthesis of hydrogen peroxide(H_(2)O_(2))from H_(2)O and O_(2)is considered to be a promising approach.However,limited to the rapid recombination of photo-generated carriers and sluggish kinetics of O_(2)re-duction to H_(2)O_(2),it is a challenge for polymeric photocatalysts to achieve efficient photocatalytic H_(2)O_(2) production.Herein,Ag single atoms and nitrogen defects decorated carbon nitride(Ag@MCT)are con-structed through self-assembly and pyrolysis methods.The optimized photocatalyst displays exceptional performance in pure water,with an H_(2)O_(2) production rate of as high as 528.4μmol g^(-1) h^(-1) and an apparent quantum yield for H_(2)O_(2)production of 4.5%at 420 nm.Experimental and theoretical results reveal that the Ag atomic sites act as electron mediators that promote the capture and transfer of photo-generated charge carriers,while nitrogen defects as electron collectors and reaction sites to enhance the adsorption and activation of O_(2),accelerating reduction kinetics from O_(2) to H_(2)O_(2).This work presents a re-liable strategy to design excellent photocatalysts by rationally modulating electronic structures and active sites for accelerating photo-generated charge carriers transfer and surface reaction kinetics.展开更多
In this study,we present the fabrication of vertical SnO/β-Ga_(2)O_(3) heterojunction diode(HJD)via radio frequency(RF)reactive magnetron sputtering.The valence and conduction band offsets betweenβ-Ga_(2)O_(3) and S...In this study,we present the fabrication of vertical SnO/β-Ga_(2)O_(3) heterojunction diode(HJD)via radio frequency(RF)reactive magnetron sputtering.The valence and conduction band offsets betweenβ-Ga_(2)O_(3) and SnO are determined to be 2.65and 0.75 eV,respectively,through X-ray photoelectron spectroscopy,showing a type-Ⅱband alignment.Compared to its Schottky barrier diode(SBD)counterpart,the HJD presents a comparable specific ON-resistances(R_(on,sp))of 2.8 mΩ·cm^(2) and lower reverse leakage current(I_R),leading to an enhanced reverse blocking characteristics with breakdown voltage(BV)of 1675 V and power figure of merit(PFOM)of 1.0 GW/cm~2.This demonstrates the high quality of the SnO/β-Ga_(2)O_(3) heterojunction interface.Silvaco TCAD simulation further reveals that electric field crowding at the edge of anode for the SBD was greatly depressed by the introduction of SnO film,revealing the potential application of SnO/β-Ga_(2)O_(3) heterojunction in the futureβ-Ga_(2)O_(3)-based power devices.data mining,AI training,and similar technologies,are reserved.展开更多
Hydrogen,as a cheap,clean,and cost-effective secondary energy source,performs an essential role in optimizing today’s energy structure.Magnesium hydride(Mg H_(2))represents an attractive hydrogen carrier for storage ...Hydrogen,as a cheap,clean,and cost-effective secondary energy source,performs an essential role in optimizing today’s energy structure.Magnesium hydride(Mg H_(2))represents an attractive hydrogen carrier for storage and transportation,however,the kinetic behavior and operating temperature remain undesirable.In this work,a dual-phase multi-site alloy(Ms A)anchored on carbon substrates was designed,and its superior catalytic effects on the hydrogen storage properties of MgH_(2) were reported.Mechanism analysis identified that multi-site Fe Ni_(3)/Ni Cu nanoalloys synergistically served as intrinsic drivers for the striking de/hydrogenation performance of the MgH_(2)-Ms A systems.Concretely,the unique multi-metallic site structure attached to the surface of MgH_(2)provided substantial reversible channels and accessible active sites conducive to the adsorption,activation,and nucleation of H atoms.In addition,the coupling system formed by FeNi_(3) and NiCu dual-phase alloys further enhanced the reactivity between Mg/MgH_(2) and H atoms.Hence,the onset dehydrogenation temperature of Mg H_(2)+5 wt%Ms A was reduced to 195℃ and the hydrogen desorption apparent activation energy was reduced to 83.6 k J/mol.5.08 wt%H_(2) could be released at 250℃ in 20 min,reaching a high dehydrogenation rate of 0.254 wt%H_(2)/min,yet that for MgH_(2) at a higher temperature of 335℃ was only 0.145 wt%H_(2)/min.Then,the dehydrogenated Mg H_(2)-Ms A sample could absorb hydrogen from room temperature(30℃)and charge 3.93 wt%H_(2) at 100℃ within20 min under 3.0 MPa H_(2) pressure.Benefiting from carbon substrates,the 5 wt%Ms A doped-MgH_(2) could still maintain 6.36 wt%hydrogen capacity after 20 cycles.In conclusion,this work provides experimental rationale and new insights for the design of efficient catalysts for magnesium-based solid-state hydrogen storage materials.展开更多
基金supported by the National Natural Science Foundation of China(No.U1810208)Shanxi Province Science and Technology Major Projects,China(No.2018110100)。
文摘The nonuniform microstructure of magnesium alloy rolled sheets tends to influence their plastic deformation capacity.This study employed multi-pass restricted rolling to successfully prepare AZ31 magnesium alloy rolled sheets with a uniform microstructure,enhancing their mechanical properties.Quasi-in-situ tensile EBSD was used to investigate the effect of microstructure uniformity on the plastic deformation and fracture behavior of magnesium alloy.The results demonstrate that the nonuniformity of the magnesium alloy microstructure intensifies the strain asynchrony between adjacent grains,leading to relative misalignment and crack formation.Fine grains cannot coordinate the strain within their adjacent coarse grains,resulting in ledge formation at their common grain boundaries.Moreover,low-angle grain boundaries(LAGB)influence fracture behavior,rendering fine grains penetrated by LAGB more susceptible to becoming strain concentration areas that promote intergranular fracture and even transgranular fracture.
基金supported by Shanghai Municipal Natural Science Foundation,China(No.21ZR1446800)the National Natural Science Foundation of China(No.41877425)the Fundamental Research Funds for the Central Universities(No.226-2024-00052)。
文摘Microorganisms can colonize the surface of microplastics(MPs)to form a distinctive microbiome,known as a“plastisphere”which is regarded as an anthropogenic niche for microbial growth.However,bacterial community assembly in virgin and aging MP plastispheres across different habitats is poorly understood.This study aims to assess the variations in bacterial community assembly across different niches and habitats with an in situ ex-periment,in which constructed forest wetland(FW),natural lake wetland(LW),and lotus pond wetland(LP)were habitats,and plastispheres of virgin and aging low-density polyethylene(LDPE)MPs,as well as surround-ing wetland soils were niches.Significant niche-related differences in bacterial communities were observed,with lower diversity and enrichment of potential plastic-degrading bacteria in the plastisphere than in the soil bacterial communities.Furthermore,habitat-related differences exerted a more pronounced influence on the beta-diversity patterns of the bacterial communities.The linear regression analyses indicated that the local species pool con-tributed more to bacterial community assembly in the LW wetland,whereas the relative abundance of species was the primary factor in the LP wetland.The null model analysis indicated that plastisphere bacterial communi-ties were predominantly driven by the stochastic process,with a more deterministic assembly observed in the LP wetland and soil bacterial communities.Additionally,the primary ecological process shaping plastisphere com-munities shifted from drift in the virgin LDPE to homogenising dispersal in the aging LDPE.This study provides new insights into the fate and ecological impacts of MPs in wetlands,thereby facilitating the effective regulations of plastic pollution.
基金supported by the Innovation Capability Support Program of Shaanxi(No.2024CX-GXPT-12)the National Natural Science Foundation of China(No.22403074).
文摘Electrolytes play a key role in determining the electrochemical performance,safety,and lifespan of potassium-based batteries,making their selection and optimization a critical area of research.This study systematically investigates the effects of two major potassium-based battery electrolytes,potassium hexafluorophosphate(KPF_(6))and potassium difluorosulfonimide(KFSI)in ethylene carbonate/diethyl carbonate(EC/DEC)solvents,on battery performance,solid electrolyte interphase(SEI)stability,aluminum(Al)current collector corrosion behavior,electrochemical stability window,and dendrite growth issue.Experimental results reveal that KFSI electrolyte significantly outperforms KPF_(6)in terms of cycling stability,rate capability,and Coulombic efficiency(CE),primarily due to the formation of a high-quality SEI on electrode surface.Through X-ray photoelectron spectroscopy(XPS)and time-of-flight secondary ion mass spectrometry(TOF-SIMS)analyses,we construct the SEI structure for both electrolytes,and find that the SEI formed by KFSI is more uniform and stable.Additionally,KPF_(6)exhibits weaker corrosivity towards the Al current collector compared to KFSI due to the formation of an AlF_(3) layer with higher oxidation stability on Al surface.Furthermore,in-situ optical microscopy observations indicate that the dendrite growth in KFSI electrolyte is more uniform,preventing the aggregates.These findings provide essential experimental evidence and theoretical support for optimizing the electrolyte in potassium-based batteries.
基金This work was supported financially by Natural Science Foundation of China(Grant Nos.31971408,31670181)Forestry Technology Innovation and Extension of Jiangsu Province(Grant No.LYKJ[2019]48)+1 种基金Qing Lan Project of Jiangsu ProvinceGraduate Student Scientific Research Innovation Projects in Yangzhou University(Grant No.XKYCX18_089).
文摘The pollen intine plays important roles in pollen germination and tube growth,but related information in Ginkgo biloba remains unclear.We isolated and obtained de-exined pollen from G.biloba.Using fluorescent probes,we observed the strongest cellulose fluorescence in the pollen intine.De-esterified pectin immunolabeled with JIM5 was present throughout the entire cell wall,whereas esterified pectin recognized by the monoclonal antibody JIM7 was concentrated in some regions.Callose staining with aniline blue was observed across the entire surface of the pollen intine.These results were confirmed by Fourier Transform InfraRed(FTIR)analysis.We also used proteomic approaches to identify different proteins between mature and de-exined pollen(48h after hydration)in vitro.Based on mass spectrometry,de-exined pollen had more proteins than mature pollen,including calmodulin,serine hydroxymethyltransferase,β-galactosidase 6,and class IV chitinase.According to Gene Ontology(GO)analysis,the differentially expressed proteins were mainly associated with transportation,defense reaction,sugar metabolism,energy metabolism,signal transduction,and cell wall formation.These findings suggest that most proteins involved in pollen germination and pollen tube growth are synthesized during pollen hydration,indicating the important role of pollen hydration in the reproductive process of G.Biloba.
基金This work was supported by the National Natural Science Foundation of China(No.61233006)the Seed Industry Development Project of Shanghai,China(Grant No.2016,1-8)+1 种基金Shanghai Agriculture Applied Technology Development Program,China(Grant No.20170304)X.Y.was supported by the State Scholarship Fund of China Scholarship Council(No.201706230173).
文摘Lettuce is an important leafy vegetable that represents a significant dietary source of antioxidants and bioactive compounds.However,the levels of metabolites in different lettuce cultivars are poorly characterized.In this study,we used combined GC×GC-TOF/MS and UPLC-IMS-QTOF/MS to detect and relatively quantify metabolites in 30 lettuce cultivars representing large genetic diversity.Comparison with online databases,the published literature,standards as well using collision cross-section values enabled putative identification of 171 metabolites.Sixteen of these 171 metabolites(including phenolic acid derivatives,glycosylated flavonoids,and one iridoid)were present at significantly different levels in leaf and head type lettuces,which suggested the significant metabolomic variations between the leaf and head types of lettuce are related to secondary metabolism.A combination of the results and metabolic network analysis techniques suggested that leaf and head type lettuces contain not only different levels of metabolites but also have significant variations in the corresponding associated metabolic networks.The novel lettuce metabolite library and novel non-targeted metabolomics strategy devised in this study could be used to further characterize metabolic variations between lettuce cultivars or other plants.Moreover,the findings of this study provide important insight into metabolic adaptations due to natural and human selection,which could stimulate further research to potentially improve lettuce quality,yield,and nutritional value.
基金supported by the National Key Research and Development Program of China(No.2018YFC1800506)the National Natural Science Foundation of China(No.42107261)+1 种基金the Natural Science Foundation of Zhejiang Province,China(No.LQ22D030002)the Open Project Foundation of Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control,China(No.NUEORS202001).
文摘Chemical immobilization is one of the most effective technologies for remediating sites with heavy metals,but the selection of proper immobilization material and determination of its dose ratio is a challenge that limits the remediation efficiency.In this study,we conducted a meta-analysis of 489 independent observations on the immobilization of heavy metals,in which the immobilization materials were divided into biochar,phosphate,lime,metal oxides,and clay minerals.The statistical analysis of these observations revealed that the material dose ratio was the most important parameter that controlled immobilization efficiency,and the Freundlich adsorption model was successfully applied to calculate the bioavailable heavy metal(BHM)concentration after immobilization.Based on the calculation results,phosphate was the most effective material for Pb immobilization.Lime was the most effective when the initial bioavailable Cd content was 0.1–1 mg kg^(-1),whereas the immobilization effects of lime and phosphate were similar when the initial bioavailable Cd content was 10 mg kg^(-1).In addition to the material dose ratio,initial soil pH(pHi)and organic matter(OM)content were negatively correlated,whereas the fraction of initial BHMs before immobilization(FB)and immobilization time were positively correlated with immobilization efficiency.A numerical model that considered the material dose ratio,pHi,OM,FB,and immobilization time was established to calculate the residual BHM concentration after immobilization.However,these factors only explained less than 45%of the immobilization effect,indicating that other factors,such as the sub-type of the material and modification methods,also affect the immobilization effect.These results could help to optimize the type of immobilization material of heavy metals and its dose ratio in practical engineering applications.
基金Project supported by the financial support from the National Key R&D Program of China(Grant No.2021YFB3201100)the National Natural Science Foundation of China(Grant No.52172128)the Top Young Talents Programme of Xi’an Jiaotong University.
文摘The stable sub-angstrom resolution of the aberration-corrected scanning transmission electron microscope(ACSTEM)makes it an advanced and practical characterization technique for all materials.Owing to the prosperous advancement in computational technology,specialized software and programs have emerged as potent facilitators across the entirety of electron microscopy characterization process.Utilizing advanced image processing algorithms promotes the rectification of image distortions,concurrently elevating the overall image quality to superior standards.Extracting high-resolution,pixel-level discrete information and converting it into atomic-scale,followed by performing statistical calculations on the physical matters of interest through quantitative analysis,represent an effective strategy to maximize the value of electron microscope images.The efficacious utilization of quantitative analysis of electron microscope images has become a progressively prominent consideration for materials scientists and electron microscopy researchers.This article offers a concise overview of the pivotal procedures in quantitative analysis and summarizes the computational methodologies involved from three perspectives:contrast,lattice and strain,as well as atomic displacements and polarization.It further elaborates on practical applications of these methods in electronic functional materials,notably in piezoelectrics/ferroelectrics and thermoelectrics.It emphasizes the indispensable role of quantitative analysis in fundamental theoretical research,elucidating the structure–property correlations in high-performance systems,and guiding synthesis strategies.
基金supported by National Natural Science Foundation of China(22279018)National Natural Science Foundation of China(22005055)Natural Science Foundation of Fujian Province(2022J01085).
文摘Solid oxide cells(SOCs)are emerging devices for efficient energy storage and conversion.However,during SOC operation,gaseous chromium(Cr)species released from Fe-Cr alloy interconnect can lead to Cr deposition and poisoning of air electrodes,causing substantial degradation in electrochemical performance and compromising the longterm stability of SOCs.This mini-review examines the mechanism of Cr deposition and poisoning in air electrodes under both fuel-cell and electrolysis modes.Furthermore,emphasis is placed on the recent advancements in strategies to mitigate Cr poisoning,offering insights into the rational design and development of active and Cr-tolerant air electrodes for SOCs.
基金supported by the Open Fund of the Laboratory for Earth Surface Processes,Ministry of Education,Peking University,Beijing,China,and the Cultivation Fund Program for Excellent Dissertation in Fujian Normal University,China(No.LWPYS202315)the Research Start-up Fund of Fujian Normal University,China(No.Y0720304X13).
文摘Fifty agricultural soil samples collected from Fuzhou,southeast China,were first investigated for the occurrence,distribution,and potential risks of twelve organophosphate esters(OPEs).The total concentration of OPEs(ΣOPEs)in soil ranged from 1.33 to 96.5 ng/g dry weight(dw),with an average value of 17.1 ng/g dw.Especially,halogenated-OPEs were the predominant group with amean level of 9.75 ng/g dw,and tris(1-chloro-2-propyl)phosphate(TCIPP)was the most abundant OPEs,accounting for 51.1%ofΣOPEs.The concentrations of TCIPP andΣOPEs were found to be significantly higher(P<0.05)in soils of urban areas than those in suburban areas.In addition,the use of agricultural plastic films and total organic carbon had a positive effect on the occurrence of OPE in this study.The positive matrix factorization model suggested complex sources of OPEs in agricultural soils from Fuzhou.The ecological risk assessment demonstrated that tricresyl phosphate presented a medium risk to land-based organisms(0.1≤risk quotient<1.0).Nevertheless,the carcinogenic and noncarcinogenic risks for human exposure to OPEs through soil ingestion and dermal absorption were negligible.These findings would facilitate further investigations into the pollution management and risk control of OPEs.
基金supported by the National Key Research and Development Plan of the Ministry of Science and Technology,China(Grant No.:2022YFE0125300)the National Natural Science Foundation of China(Grant No:81690262)+2 种基金the National Science and Technology Major Project,China(Grant No.:2017ZX09201004-021)the Open Project of National facility for Translational Medicine(Shanghai),China(Grant No.:TMSK-2021-104)Shanghai Jiao Tong University STAR Grant,China(Grant Nos.:YG2022ZD024 and YG2022QN111).
文摘Liposomes serve as critical carriers for drugs and vaccines,with their biological effects influenced by their size.The microfluidic method,renowned for its precise control,reproducibility,and scalability,has been widely employed for liposome preparation.Although some studies have explored factors affecting liposomal size in microfluidic processes,most focus on small-sized liposomes,predominantly through experimental data analysis.However,the production of larger liposomes,which are equally significant,remains underexplored.In this work,we thoroughly investigate multiple variables influencing liposome size during microfluidic preparation and develop a machine learning(ML)model capable of accurately predicting liposomal size.Experimental validation was conducted using a staggered herringbone micromixer(SHM)chip.Our findings reveal that most investigated variables significantly influence liposomal size,often interrelating in complex ways.We evaluated the predictive performance of several widely-used ML algorithms,including ensemble methods,through cross-validation(CV)for both lipo-some size and polydispersity index(PDI).A standalone dataset was experimentally validated to assess the accuracy of the ML predictions,with results indicating that ensemble algorithms provided the most reliable predictions.Specifically,gradient boosting was selected for size prediction,while random forest was employed for PDI prediction.We successfully produced uniform large(600 nm)and small(100 nm)liposomes using the optimised experimental conditions derived from the ML models.In conclusion,this study presents a robust methodology that enables precise control over liposome size distribution,of-fering valuable insights for medicinal research applications.
基金supported by Natural Science Foundation of Liaoning Province of China under Grant No.2020-MS-085。
文摘The morphology and dimension of W phases play an important role in determining mechanical properties of Mg-RE-Zn(where RE denotes rare earth elements)alloys.In this study,theγ′platelet and W particle occurred in the aged Mg-2Dy-0.5Zn(at.%)alloys were investigated by aberration-corrected scanning transmission electron microscopy.A novel formation mechanism of W phase was proposed,and its effects on the morphology and dimension of W particle,as well as mechanical properties of Mg-2Dy-0.5Zn alloys,were also discussed particularly.Different from other Mg-RE-Zn alloys,the nucleation and growth of W particle in Mg-Dy-Zn alloys mainly depend on the precipitatedγ′platelet.Primarily,a mass of Dy and Zn solute atoms concentrated nearγ′platelet or between two adjacentγ′platelets can meet the composition requirement of W particle nucleation.Next,the smaller interfacial mismatch between W andγ′facilitates the nucleation and growth of W particle.Thirdly,the growth of W particle can be achieved by consuming the surroundingγ′platelets.The nucleation and growth mechanisms make W particles exhibit rectangular or leaf-like and remain at the nanoscale.The coexistence ofγ′platelets and nanoscale W particles,and some better interfacial relationships between phases,lead to a high strength-ductility synergy of alloy.The findings may provide some fundamental guidelines for the microstructure design and optimization of new-type Mg-based alloys.
基金financial support from the Doctoral Foundation of Henan University of Engineering(No.D2022025)National Natural Science Foundation of China(No.U2004162)+1 种基金National Natural Science Foundation of China(No.52302138)Key Project for Science and Technology Development of Henan Province(No.232102320221)。
文摘With the rapid development of electric vehicles,hybrid electric vehicles and smart grids,people's demand for large-scale energy storage devices is increasingly intense.As a new type of secondary battery,potassium ion battery is promising to replace the lithium-ion battery in the field of large-scale energy storage by virtue of its low price and environmental friendliness.At present,the research on the anode materials of potassium ion batteries mainly focuses on carbon materials and the design of various nanostructured metal-based materials.Problems such as poor rate performance and inferior cycle life caused by electrode structure comminution during charge and discharge have not been solved.Quantum dots/nanodots materials are a new type of nanomaterials that can effectively improve the utilization of electrode materials and reduce production costs.In addition,quantum dots/nanodots materials can enhance the electrode reaction kinetics,reduce the stress generated in cycling,and effectively alleviate the agglomeration and crushing of electrode materials.In this review,we will systematically introduce the synthesis methods,K+storage properties and K+storage mechanisms of carbon quantum dots and carbon-based transition metal compound quantum dots composites.This review will have significant references for potassium ion battery researchers.
基金supported by the Natural Science Foundation of Liaoning Province(2023-MSBA-020)the Fundamental Research Funds for Central Universities(DUT24MS020)Science and Technology Innovation Fund of Dalian(2022JJ13SN073).
文摘Ferroptosis is a novel form of cell death driven by oxidative damage,and is implicated in various pathological conditions,including neurodegenerative diseases,retinal damage,and ischemia-reperfusion injury of organs.Inhibiting ferroptosis has shown great promise as a therapeutic strategy for these diseases,underscoring the urgent need to develop effective ferroptosis inhibitors.Although Ferrostatin-1(Fer-1)is a potent ferroptosis inhibitor,its susceptibility to oxidation and metabolic inactivation limits its clinical utility.In this study,the accumulation of peroxides and the resulting oxidative damage in the cellular microenvironment during ferroptosis were utilized to design Ferrostatin-1 prodrugs with reactive oxygen species-responsive features.This approach led to the development of a series of ferroptosis inhibitors that were capable of recognizing oxidative damage in diseased areas,allowing for targeted release and improved stability.The novel compounds demonstrated significant inhibitory effects and selectivity against RSL-3-induced ferroptosis in HK-2 cells,with compound a1 exhibiting an EC50 of 15.4�0.7μM,outperforming Fer-1.These compounds effectively identify the oxidative microenvironment associated with ferroptosis,enabling the targeted release of Fer-1,which prevents lipid peroxide accumulation and inhibits ferroptosis.This strategy holds promise for treating diseases related to ferroptosis,offering a targeted and intelligent therapeutic approach.
基金Inner Mongolia Natural Science Foundation Project(2020LH05028)。
文摘Impact of texture type on the magnetic properties of ultrahigh density perpendicular magnetic recording media L1_(0)-FePt thin film was investigated,so were the texture formation and evolution mechanism.Reuss,Voigt,and Hill models were used to determine the anisotropic elastic modulus of L1_(0)-FePt thin film with fiber texture.Then,the elastic strain energies of thin films under various stress conditions were calculated.Results reveal that the stress condition has a significant influence on the fiber texture evolution.When the L1_(0)-FePt thin film is subjected to compressive in-plane strain prior to ordering phase transformation,the formation of{100}fiber texture is promoted.On the contrary,the ordering phase transformation under tensile in-plane strain promotes the{001}fiber texture formation.
基金financial support from the National Natural Science Foundation of China(No.51801078).
文摘To modify the stable thermodynamics and poor kinetics of magnesium hydride(MgH_(2))for solid-state hydrogen storage,MIL-100(Fe)was in situ fabricated on the surfaces of TiO_(2)nano-sheets(NS)by a self-assembly method,and the prepared TiO_(2)NS@MIL-100(Fe)presents an excellent catalytic effect on MgH_(2).The MgH_(2)+7wt.%TiO_(2)NS@MIL-100(Fe)composite can release hydrogen at 200℃,achieving a decrease of 150℃ compared to pure MgH_(2).Besides,the activation energy of dehydrogenation is decreased to 70.62 kJ/mol and 4 wt.%H_(2) can be desorbed within 20 min at a low temperature of 235℃.Under conditions of 100℃ and 3 MPa,MgH_(2)+7wt.%TiO_(2)NS@MIL-100(Fe)absorbs 5 wt.%of H_(2) in 10 min.Surprisingly,6.62 wt.%reversible capacity is maintained after 50 cycles.The modification mechanism is confirmed that the presence of oxygen vacancies and the synergistic effect of multivalent titanium in TiO_(2)NS@MIL-100(Fe)greatly enhance the kinetic and thermodynamic properties of MgH_(2).
基金supported by the National Natural Science Foundation of China(No.52005362)the Fundamental Research Program of Shanxi Province(Nos.202303021221005 and 202303021211045)+1 种基金the Patent Commercialization Program of Shanxi Province(No.202402003)the Key Research and Development Plan of Xinzhou City.
文摘Presetting tensile twins(TTs)can enhance the mechanical properties of magnesium(Mg)alloys.Two as-received(AR)sheets,as-received state-A(AR-A)with fiber texture and nonuniform grains and as-received state-B with basal texture and uniform equiaxial grains are selected to induce TTs via a novel method called corrugated wide limit alignment(CWLA),and the corresponding CWLA-processed sheets are denoted as CWLA-processed state-A(C-A)and CWLA-processed state-B(C-B).The results demonstrate that a larger initial average grain size correlates with a higher fraction of TTs induced in Mg sheets,thereby refining the grains and forming a new rolling direction(RD)tilted texture during CWLA.The ultimate tensile strength increases by 32%from AR-A to C-A,primarily due to refinement strengthening and twinning-induced strain hardening.The recrystallization mechanism of C-A is dominated by twinning-induced dynamic recrystallization(DRX),where DRX grains prefer to inherit the orientation of TTs,resulting in an enhanced RD-tilted texture and the formation of multi-modal texture.The recrystallization mechanism of C-B is mainly discontinuous DRX and continuous DRX,and the DRX grains prefer to inherit the orientation of matrix grains,ultimately forming a basal texture.In summary,the tensile mechanical behavior of pre-twinned Mg sheets significantly depends on the grain size and texture of the AR sheets,so they present similar changing trends during tensile deformation.
基金Project supported by the Bingtuan Science and Technology Program(2024DA036,2022ZD099)。
文摘Introducing vacancies and constructing S-scheme heterojunctions are promising approaches for enhancing photocatalytic activity.However,the application of this synergistic strategy to realize inexpensive and efficient photocatalysts remains challenging.In this study,a straightforward hydrothermal and calcination modification strategy was used to prepare a photocatalyst in which abundant nitrogen-oxygen vacancies were coupled with a Ce-ZnO@C-g-C_(3)N_(4)composite with an S-scheme heterojunction.Under sunlight irradiation,the prepared composite achieves 98.3%and 86.4%degradation of methylene blue and ciprofloxacin,with degradation rate constants of 0.3464 and 0.0893 min^(-1),respectively.Compared with ZnO and g-C_(3)N_(4),the degradation rates of methylene blue over the composite catalyst are 34.8 and 22.7 times higher,respectively,and those of ciprofloxacin are 2.4 and 4.9 times higher,respectively.Based on a detailed examination of the catalyst structure and photoelectric properties,the high photocatalytic efficiency is attributed to nitrogen-oxygen vacancies,an enhanced surface area,and synergistic S-scheme heterojunction effects.These factors broaden the spectral range,increase the number of active sites,and facilitate efficient charge transfer,thereby enhancing the photocatalytic reaction.This system demonstrates the feasibility of integrating doping and heterojunction formation to enhance photocatalytic performance synergistically.
基金supported by the Basic Science Center Program for Ordered Energy Conversion of the National Natural Science Foundation of China(No.52488201)the National Natural Science Foundation of China(No.52276213)+1 种基金the Key Research and Development Program of Shaanxi Province(No.2024GX-YBXM-459)the Fundamental Research Funds for the Central Universities.
文摘Photosynthesis of hydrogen peroxide(H_(2)O_(2))from H_(2)O and O_(2)is considered to be a promising approach.However,limited to the rapid recombination of photo-generated carriers and sluggish kinetics of O_(2)re-duction to H_(2)O_(2),it is a challenge for polymeric photocatalysts to achieve efficient photocatalytic H_(2)O_(2) production.Herein,Ag single atoms and nitrogen defects decorated carbon nitride(Ag@MCT)are con-structed through self-assembly and pyrolysis methods.The optimized photocatalyst displays exceptional performance in pure water,with an H_(2)O_(2) production rate of as high as 528.4μmol g^(-1) h^(-1) and an apparent quantum yield for H_(2)O_(2)production of 4.5%at 420 nm.Experimental and theoretical results reveal that the Ag atomic sites act as electron mediators that promote the capture and transfer of photo-generated charge carriers,while nitrogen defects as electron collectors and reaction sites to enhance the adsorption and activation of O_(2),accelerating reduction kinetics from O_(2) to H_(2)O_(2).This work presents a re-liable strategy to design excellent photocatalysts by rationally modulating electronic structures and active sites for accelerating photo-generated charge carriers transfer and surface reaction kinetics.
基金supported by the National Natural Science Foundation of China(NSFC,No.62074048)the Key Research and Development Plan of Anhui Province(No.2022f04020007)the Natural Science Foundation of Anhui Province(No.2208085MF177)。
文摘In this study,we present the fabrication of vertical SnO/β-Ga_(2)O_(3) heterojunction diode(HJD)via radio frequency(RF)reactive magnetron sputtering.The valence and conduction band offsets betweenβ-Ga_(2)O_(3) and SnO are determined to be 2.65and 0.75 eV,respectively,through X-ray photoelectron spectroscopy,showing a type-Ⅱband alignment.Compared to its Schottky barrier diode(SBD)counterpart,the HJD presents a comparable specific ON-resistances(R_(on,sp))of 2.8 mΩ·cm^(2) and lower reverse leakage current(I_R),leading to an enhanced reverse blocking characteristics with breakdown voltage(BV)of 1675 V and power figure of merit(PFOM)of 1.0 GW/cm~2.This demonstrates the high quality of the SnO/β-Ga_(2)O_(3) heterojunction interface.Silvaco TCAD simulation further reveals that electric field crowding at the edge of anode for the SBD was greatly depressed by the introduction of SnO film,revealing the potential application of SnO/β-Ga_(2)O_(3) heterojunction in the futureβ-Ga_(2)O_(3)-based power devices.data mining,AI training,and similar technologies,are reserved.
基金financial supports from the National Key R&D Program of China(No.2020YFA0406204)the National Natural Science Foundation of China(No.51801078)。
文摘Hydrogen,as a cheap,clean,and cost-effective secondary energy source,performs an essential role in optimizing today’s energy structure.Magnesium hydride(Mg H_(2))represents an attractive hydrogen carrier for storage and transportation,however,the kinetic behavior and operating temperature remain undesirable.In this work,a dual-phase multi-site alloy(Ms A)anchored on carbon substrates was designed,and its superior catalytic effects on the hydrogen storage properties of MgH_(2) were reported.Mechanism analysis identified that multi-site Fe Ni_(3)/Ni Cu nanoalloys synergistically served as intrinsic drivers for the striking de/hydrogenation performance of the MgH_(2)-Ms A systems.Concretely,the unique multi-metallic site structure attached to the surface of MgH_(2)provided substantial reversible channels and accessible active sites conducive to the adsorption,activation,and nucleation of H atoms.In addition,the coupling system formed by FeNi_(3) and NiCu dual-phase alloys further enhanced the reactivity between Mg/MgH_(2) and H atoms.Hence,the onset dehydrogenation temperature of Mg H_(2)+5 wt%Ms A was reduced to 195℃ and the hydrogen desorption apparent activation energy was reduced to 83.6 k J/mol.5.08 wt%H_(2) could be released at 250℃ in 20 min,reaching a high dehydrogenation rate of 0.254 wt%H_(2)/min,yet that for MgH_(2) at a higher temperature of 335℃ was only 0.145 wt%H_(2)/min.Then,the dehydrogenated Mg H_(2)-Ms A sample could absorb hydrogen from room temperature(30℃)and charge 3.93 wt%H_(2) at 100℃ within20 min under 3.0 MPa H_(2) pressure.Benefiting from carbon substrates,the 5 wt%Ms A doped-MgH_(2) could still maintain 6.36 wt%hydrogen capacity after 20 cycles.In conclusion,this work provides experimental rationale and new insights for the design of efficient catalysts for magnesium-based solid-state hydrogen storage materials.