Ensuring national food security amidst rapid population growth and increasing extreme weather events remains a critical global challenge.However,the extent to which agricultural modernization in China enhances grain y...Ensuring national food security amidst rapid population growth and increasing extreme weather events remains a critical global challenge.However,the extent to which agricultural modernization in China enhances grain yield and contributes to food security remains unclear.Therefore,using panel data from 327 Chinese cities(2013–2021),this study employs spatial econometric models to analyze the spatial spillover effects of agricultural modernization level(AML)on grain yield and to reveal regional heterogeneity across nine major agricultural zones.The results showed a cumulative grain yield increase of 23.7 million tons,with peak productivity concentrated along the Hu Line and declining eastward and westward.AML also exhibited a steady increase but a clear spatial gradient,decreasing from coastal to inland regions,with the highest level observed in Southern China(SC).A key finding was that a 1%increase in AML directly raised local grain yield by an average of 4.185%,accompanied by significant positive spillover effects on neighboring regions.Regional variations revealed distinct patterns:the direct effects of AML were more pronounced in southern and eastern zones,while spillover effects dominated in northern and western zones.The largest positive direct impact of AML on grain yield was observed in the SC(8.499%),while Middle-Lower Yangtze Plain ranked second but exhibited the strongest positive spatial spillover effect(4.534%).These findings highlight the critical role of agricultural modernization in promoting grain production and provide a solid basis for optimizing regional agricultural systems,ensuring food security,and advancing sustainable agriculture.展开更多
Root-zone temperature(RZT)strongly affects plant growth,nutrient uptake and tolerance to environmental stress,making its regulation a key challenge in greenhouse cultivation in cold climates.This study aimed to assess...Root-zone temperature(RZT)strongly affects plant growth,nutrient uptake and tolerance to environmental stress,making its regulation a key challenge in greenhouse cultivation in cold climates.This study aimed to assess the potential of passive techniques,namely black polyethylene mulch and row covers,for modifying RZT dynamics in lettuce(Lactuca sativa L.)production and to evaluate the predictive performance of the eXtreme Gradient Boosting(XGBoost)algorithm.Experiments were conducted in Iğdır,Türkiye,over a 61-day period,with soil temperature continuously monitored at depths of 1-30 cm under mulched and non-mulched conditions,alongside measurements of greenhouse air temperature both with and without row covers.The application of row covers increased internal air temperature by 5.8℃,while mulching raised RZT by 0.6-1.3℃,with effects diminishing at deeper layers.XGBoost modeling achieved high predictive accuracy,with RMSE values of 0.150-0.189◦C and R^(2)values above 0.99,and feature-importance analysis indicated that neighboring soil depths were the strongest predictors of RZT.These findings show that integrating row covers and mulching can stabilize the root-zone microclimate without active heating.The XGBoost model provides a robust tool for forecasting soil temperature and supports sustainable greenhouse production in cold regions.展开更多
AIM:To investigate the impact of preoperative anterior corneal topographic parameters on the morphology of the postoperative effective optical zone(EOZ)in patients undergoing keratorefractive lenticule extraction(KLEx...AIM:To investigate the impact of preoperative anterior corneal topographic parameters on the morphology of the postoperative effective optical zone(EOZ)in patients undergoing keratorefractive lenticule extraction(KLEx)and wavefront-guided LASIK(WG-LASIK).METHODS:This retrospective study included 310 eyes from patients who underwent either KLEx(via small incision lenticule extraction,171 eyes)or WG-LASIK(139 eyes).Patients were stratified into subgroups based on the median values of spherical equivalent(SE)and anterior corneal topographic parameters.Postoperative EOZ parameters were measured 1mo after surgery and compared across subgroups.Correlation analysis and multivariable linear regression analysis were performed to explore the associations between preoperative anterior corneal topographic parameters and EOZ parameters.RESULTS:A total of 310 eyes were included(KLEx:171 eyes from 88 patients;WG-LASIK:139 eyes from 82 patients).The mean age was 30.65±5.67y in the KLEx cohort and 29.06±5.94y in the WG-LASIK cohort.In the KLEx cohort,SE,preoperative mean keratometry(Km),steep keratometry(K2),and anterior corneal astigmatism(K2-K1)were positively correlated with the postoperative optical zone reduction ratio(RR=EOZ/planned optical zone×100%;all P<0.01).Multivariable regression identified SE[β=0.027,95%confidence interval(CI):0.022-0.032,P<0.001],Km(β=0.009,95%CI:0.002-0.016,P=0.014),and anterior corneal astigmatism(β=0.031,95%CI:0.013-0.049,P<0.001)as significant predictors of RR(R²=0.456,P<0.001).In the WG-LASIK cohort,SE was positively correlated with RR(P<0.01);K2 and anterior corneal astigmatism were positively correlated with both RR(P<0.05)and EOZ eccentricity(P<0.01).Multivariable regression showed SE(β=0.015,95%CI:0.007-0.023,P<0.001)and anterior corneal astigmatism(β=0.029,95%CI:0.012-0.047,P=0.001)were significant predictors of RR(R²=0.121,P<0.001).CONCLUSION:Preoperative anterior corneal topographic parameters,particularly anterior corneal astigmatism,significantly affect postoperative EOZ morphology in both KLEx and WG-LASIK.Additionally,Km is a predictor of EOZ reduction specifically in KLEx.展开更多
The strength of the sliding zone soil determines the stability of reservoir landslides.Fluctuations in water levels cause a change in the seepage field,which serves as both the external hydrogeological environment and...The strength of the sliding zone soil determines the stability of reservoir landslides.Fluctuations in water levels cause a change in the seepage field,which serves as both the external hydrogeological environment and the internal component of a landslide.Therefore,considering the strength changes of the sliding zone with seepage effects,they correspond with the actual hydrogeological circumstances.To investigate the shear behavior of sliding zone soil under various seepage pressures,24 samples were conducted by a self-developed apparatus to observe the shear strength and measure the permeability coefficients at different deformation stages.After seepage-shear tests,the composition of clay minerals and microscopic structure on the shear surface were analyzed through X-ray and scanning electron microscope(SEM)to understand the coupling effects of seepage on strength.The results revealed that the sliding zone soil exhibited strain-hardening without seepage pressure.However,the introduction of seepage caused a significant reduction in shear strength,resulting in strain-softening characterized by a three-stage process.Long-term seepage action softened clay particles and transported broken particles into effective seepage channels,causing continuous damage to the interior structure and reducing the permeability coefficient.Increased seepage pressure decreased the peak strength by disrupting occlusal and frictional forces between sliding zone soil particles,which carried away more clay particles,contributing to an overhead structure in the soil that raised the permeability coefficient and decreased residual strength.The internal friction angle was less sensitive to variations in seepage pressure than cohesion.展开更多
This work focuses on the influence of Al content on the precipitation of nanoprecipitates,growth of prior austenite grains(PAGs),and impact toughness in simulated coarse-grained heat-affected zones (CGHAZs) of two exp...This work focuses on the influence of Al content on the precipitation of nanoprecipitates,growth of prior austenite grains(PAGs),and impact toughness in simulated coarse-grained heat-affected zones (CGHAZs) of two experimental shipbuilding steels after being subjected to high-heat input welding at 400 kJ·cm^(-1).The base metals (BMs) of both steels contained three types of precipitates Type Ⅰ:cubic (Ti,Nb)(C,N),Type Ⅱ:precipitate with cubic (Ti,Nb)(C,N) core and Nb-rich cap,and Type Ⅲ:ellipsoidal Nb-rich precipitate.In the BM of 60Al and 160Al steels,the number densities of the precipitates were 11.37×10^(5) and 13.88×10^(5) mm^(-2),respectively The 60Al and 160Al steel contained 38.12% and 6.39% Type Ⅲ precipitates,respectively.The difference in the content of Type Ⅲ precipitates in the 60Al steel reduced the pinning effect at the elevated temperature of the CGHAZ,which facilitated the growth of PAGs The average PAG sizes in the CGHAZ of the 60Al and 160Al steels were 189.73 and 174.7μm,respectively.In the 60Al steel,the low lattice mismatch among Cu_(2)S,TiN,and γ-Al_(2)O_(3)facilitated the precipitation of Cu_(2)S and TiN onto γ-Al_(2)O_(3)during welding,which decreased the number density of independently precipitated (Ti,Nb)(C,N) particles but increased that of γ-Al_(2)O_(3)–Ti N–Cu_(2)S particles.Thus abnormally large PAGs formed in the CGHAZ of the 60Al steel,and they reached a maximum size of 1 mm.These PAGs greatly reduced the microstructural homogeneity and consequently decreased the impact toughness from 134 (0.016wt%Al) to 54 J (0.006wt%Al)at-40℃.展开更多
As the mine depth around the world increases,the temperature of the surrounding rock of the mining workface increases significantly.To control the heat hazards,the hot water in the mining floor is developed during min...As the mine depth around the world increases,the temperature of the surrounding rock of the mining workface increases significantly.To control the heat hazards,the hot water in the mining floor is developed during mining to decrease the min-ing workface temperature while also developing geothermal energy.This method is called the co-exploitation of mine and geothermal energy(CMGE).The geothermal development may precipitate the large-scale failure of the nearby fault zone during the mining process.However,the evolution of shear slide and shear failure of fault under geothermal production/rein-jection during mining is missing.Therefore,a fully-coupled hydraulic mechanism(HM)double-medium model for CMGE was developed based on the measured data of the Chensilou mine.A comparative analysis of the mechanical response of fault between CMGE and single mining was conducted.The disturbance of geothermal production pressure and reinjection pressure under mining on fault stability were respectively expounded.The results indicate that:(1)The disturbance of geo-thermal reinjection amplifies the disturbance of mining on fault stability.The amplified effect resulted in a normal stress drop of the fault,further leading to a substantial increase in shear slide distance,failure area,and cumulative seismic moment of fault compared with the single mining process.(2)As the distance of reinjection well to the fault decreases,the fault failure intensity increases.Setting the production well within the fault is advantageous for controlling fault stability under CMGE.(3)The essence of the combined disturbance of CMGE on the nearby fault is the overlay of tensile stress disturbance on the fault rock mass of the mining and geothermal reinjection.Though the geothermal reinjection causes a minor normal stress drop of fault,it can result in a more serious fault failure under CMGE.This paper supplies a significant gap in understanding thenearby faults failure under CMGE.展开更多
AIM:To observe the effect of the plus power ring zone(PPRZ)area and distribution on myopia progression.METHODS:This retrospective study enrolled 137 pre-teens aged 8-12 at Taiyuan Aier Eye Hospital between 2019 and 20...AIM:To observe the effect of the plus power ring zone(PPRZ)area and distribution on myopia progression.METHODS:This retrospective study enrolled 137 pre-teens aged 8-12 at Taiyuan Aier Eye Hospital between 2019 and 2021.They were fitted with Ortho-K lenses for the first time due to refractive error,with a one-year follow-up period.To indicate the peripheral plus ring zone overlapping with the pupil zone(PPROPZ)accompanying PPRZ,participants were divided based on the PPROPZ to PPRZ ratio.The experimental group had 103 eyes with a PPROPZ to PPRZ ratio of≥0.2,and the control group had 103 eyes with a ratio of<0.2.Participants had a spherical diopter in the range of-6.00 D to-0.75 D,against-the-rule astigmatism less than 1.00 D,with-the-rule astigmatism less than 1.50 D,and corneal curvatures of 39.00 D to 46.00 D.They had a stable best corrected visual acuity of 0.10 LogMAR(20/25)or better when wearing orthokeratology(Ortho-K)lenses.PPRZ and PPROPZ were measured using ImageJ;corneal topography assessed corneal-related parameters,and an optical biometer measured the axial length of the eyes pre and post-one years of lens wear.RESULTS:Changes in axial length elongation were found to decrease when either the PPRZ(P<0.01)or PPROPZ(P<0.001)was increased significantly.The axial length growth was faster in the control group(0.37±0.2 mm)than in the experimental group(0.21±0.11 mm).Furthermore,we found that a larger horizontal visible iris diameter(HVID)corresponded to slower axial growth of the eye.In contrast,axial length growth showed no correlation with surface regularity index(SRI),surface asymmetry index(SAI),flat keratometry value(K_(f)),steep keratometry value(K_(s)).CONCLUSION:For orthokeratology,wearers with larger PPROPZ to PPRZ ratio usually experiences a reduction in axial length growth.The PPRZ and PPROPZ are negatively correlated with the axial length.Our findings provide a recommendation and methods for studying the myopia control mechanism through Ortho-K lenses.展开更多
Exploring the specific environmental impacts and mechanisms of China’s sustainable development pilot policy can enrich and expand China’s institutional and practical experiences,offering valuable insights and refere...Exploring the specific environmental impacts and mechanisms of China’s sustainable development pilot policy can enrich and expand China’s institutional and practical experiences,offering valuable insights and references for advancing global environmental sustainability.This study selects the National Innovation Demonstration Zone for Sustainable Development Agenda(NIDZSDA)as the sample and empirically evaluates the effects of the policy on urban environmental quality,using panel data from 74 prefecture-level cities in China between 2006 and 2020.The findings indicate that the sustainable development policy significantly improves urban environmental quality.Two key mechanisms identified are the aggregation of high-quality talent and the enhancement of technological innovation capabilities.Furthermore,the policy exhibits heterogeneous effects across different types of cities,with more pronounced improvements observed in mega and super cities,as well as in resource-based cities.展开更多
Herein,3‑aminopropyltriethoxysilane(APTES)was used to modify F‑containing silica slag(SS)by simple grafting and served as a multifunctional barrier layer.The amino group(—NH2)in the amino‑modified SS(NH2‑SS)forms lig...Herein,3‑aminopropyltriethoxysilane(APTES)was used to modify F‑containing silica slag(SS)by simple grafting and served as a multifunctional barrier layer.The amino group(—NH2)in the amino‑modified SS(NH2‑SS)forms ligand bonds or hydrogen bonds with sulfur ions in lithium polysulfides(LiPSs),thus inhibiting the shuttle effect.Electrochemical analyses demonstrated that lithium‑sulfur(Li‑S)batteries employing the NH2‑SS interlayer exhibited discharge specific capacities of 1048 and 789 mAh·g^(-1) at 0.2C and 2C,respectively,and even at 4C,the initial discharge specific capacity remained at 590 mAh·g^(-1),outperforming the Li‑S battery with unmodified SS as the interlayer.展开更多
This study reconstructed the paleo-uplift and depression pattern within the sequence stratigraphic framework of the Mid-Permian Maokou Formation,Sichuan Basin,investigated its tectono-sedimentary mechanisms and its co...This study reconstructed the paleo-uplift and depression pattern within the sequence stratigraphic framework of the Mid-Permian Maokou Formation,Sichuan Basin,investigated its tectono-sedimentary mechanisms and its control on paleogeomorphology and large-sale shoals based on analysis of outcrops,loggings and seismic data.The results show that the Maokou Formation comprises two third-order sequences,six fourth-order sequences(SSQ1-SSQ6),and four distinct slope-break zones developing progressively from north to south.Slope-break zones I-III in the northern basin,controlled by synsedimentary extensional faults,exhibited a NE-trending linear distribution with gradual southeastward migration.In contrast,slope-break zone IV in the southern basin displayed an arcuate distribution along the Emeishan Large Igneous Province(ELIP).The evolutions of these multistage slope-break zones governed the Mid-Permian paleogeomorphy in the Sichuan Basin transformations from a giant,north-dipping gentle slope(higher in the southwest than in the northeast)in the early-stage(SSQ1-SSQ2)to a platform(south)-basin(north)pattern in the middle-stage(SSQ3-SSQ5).Ultimately,a further depression zone developed in the southwestern basin during the late-stage(SSQ6),forming a paleo-uplift bounded by two depressions.The developments of the Mid-Permian paleogeomorphic configuration reflected the combined control by the rapid subduction of the Mianlüe Ocean and the episodic eruptions of the Emeishan mantle plume(or hot spots),which jointly facilitated the formation of extensive high-energy shoal facies belts along slope-break zones and around paleo-volcanic uplifts.展开更多
The effect of temperature on molten zone length was investigated through simulation to optimize the control of molten zone length during the experimental process. The temperature gradient distribution within the molte...The effect of temperature on molten zone length was investigated through simulation to optimize the control of molten zone length during the experimental process. The temperature gradient distribution within the molten zone during zone refining was simulated using COMSOL Multiphysics software and experimentally validated. The simulated molten zone length showed good agreement with the actual measured length. The experimental study of tellurium purification by zone refining was conducted under the following conditions: three passes of zone refining, a hydrogen flow rate of 0.5 L/min, and molten zone movement speeds of 0.5 and 1.0 mm/min. The results demonstrated that the removal efficiencies of impurities such as Ca and Cu exceeded 95%, while the removal efficiency of phosphorus (P) reached over 70%. And the purity of tellurium reached 6N.展开更多
The interactions between clouds and aerosols represent one of the largest uncertainties in assessing the Earth's radiation budget, highlighting the importance of research on the transition zone(TZ) within the clou...The interactions between clouds and aerosols represent one of the largest uncertainties in assessing the Earth's radiation budget, highlighting the importance of research on the transition zone(TZ) within the cloud-aerosol continuum.This study assesses the global distribution of TZ conditions, analyzes its optical characteristics, and determines the cloud or aerosol types most commonly associated with them, using the cloud-aerosol discrimination(CAD) score of the CloudAerosol Lidar with Orthogonal Polarization(CALIOP) instrument on the CALIPSO satellite. The CAD score classifies clouds and aerosols by the probability density functions of attenuated backscatter, total color ratio, volume depolarization ratio, altitude, and latitude. After applying several filters to avoid artifacts, the TZ was identified as those atmospheric layers that cannot be clearly classified as clouds or aerosols, layers within the no-confidence range(NCR) of the CAD score, and cirrus fringes. The optical characteristics of NCR layers exhibit two main clusters: Cluster 1, with properties between high-altitude ice clouds and aerosols(e.g., wispy cloud fragments), and Cluster 2, with properties between water clouds and aerosols at lower altitudes(e.g., large hydrated aerosols). Our results highlight the significant ubiquity of TZ conditions, which appear in 9.5% of all profiles and comprise 6.4% of the detected layers. Cluster 1 and cirrus-fringe layers predominate near the ITCZ and in mid-latitudes, whereas Cluster 2 layers are more frequent over the oceans along the central West African and East Asian coasts, where elevated smoke and dusty marine aerosols are common.展开更多
The in-flight heating process of cerium dioxide(CeO_(2))powders was investigated through experiments and numerical simulations.In the experiment,CeO_(2)powder(average size of 30μm)was injected into radio-frequency(RF...The in-flight heating process of cerium dioxide(CeO_(2))powders was investigated through experiments and numerical simulations.In the experiment,CeO_(2)powder(average size of 30μm)was injected into radio-frequency(RF)argon plasma,and the temperatures were measured using a DPV-2000 monitor.A model combining the electromagnetism,thermal flow,and heat transfer characteristics of powder during in-flight heating in argon plasma was proposed.The melting processes of CeO_(2)powders of different diameters,with and without thermal resistance effect,were investigated.Results show that the heating process of CeO_(2)powder particles consists of three main stages,one of which is relevant to a dimensionless parameter known as the Biot number.When the Biot value≥0.1,thermal resistance increases significantly,especially for the larger powders.The predicted temperature of the particles at the outlet(1800–2880 K)is in good agreement with the experimental result.展开更多
To ensure the efficient use of resources,particularly in water-scarce arid and semi-arid regions where abiotic stress threatens food security,assessing soil and climate suitability for specific crops is crucial.Simult...To ensure the efficient use of resources,particularly in water-scarce arid and semi-arid regions where abiotic stress threatens food security,assessing soil and climate suitability for specific crops is crucial.Simultaneously,food production must align with sustainable development goals by minimizing negative environmental impacts.Therefore,establishing agro-climatic suitability using a spatiotemporal approach is essential.This involves three key steps:first,determining the climatically appropriate months based on the species’requirements(temporal suitability),and second,establishing the soil suitability of specific plots(spatial suitability).Following this,quantifying crop evapotranspiration allows for optimized water use.This study used climatic and soil variables from diverse data sources to characterize the study area.Subsequently,suitability classes for Portulaca oleracea were determined based on existing literature.Our analysis concerning temporal suitability revealed that June and July are the optimal months for sowing this species in all of the municipalities.Spatially,approximately 30%of the agricultural land use of the study area exhibits a highly suitable class in most municipalities.Both dimensions,the temporal and the spatially,were validated through Chi square(χ^(2))Goodness-of-Fit test and theχ^(2)test of independence,respectively.Consequently,for a one-month production cycle during periods of high suitability,estimated evapotranspiration values are between 210 and 245 mm.In brief,the study area demonstrates favorable agro-climatic conditions for P.oleracea cultivation in specific months of the year according to parameters used,with potential in a large proportion of agricultural land and achievable water requirements.展开更多
Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticle...Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticles were chlorinated by NaClO solution to get AgCl@SiO_(2)/CTS‑based chloramine nano‑hybrid materials,denoted as AgCl@SiO_(2)/CTS‑Cl.A transmission electron microscope was used to observe the morphology of the as‑prepared samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.At the same time,an X‑ray diffractometer and an infrared spectroscope were utilized to characterize their crystal and chemical structures.Besides,ζpotentials were measured to elucidate the surface modification of AgCl nanoparticles by—NH_(2),the antibacterial mechanism of AgCl@SiO_(2)/CTS‑Cl was investigated by scanning electron microscopy,and Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were used as the to‑be‑tested strains to evaluate the antimicrobial activity of samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.Findings demonstrate that sample AgCl@SiO_(2)/CTS exhibits a chain‑like structure ascribed to the interaction between—NH_(2),and each AgCl@SiO_(2)/CTS hybrid nanoparticle contains several AgCl cores.In the meantime,sample AgCl@SiO_(2)/CTS‑Cl exhibits excellent antibacterial activity against E.coli and S.aureus,which is attributed to the synergistic antibacterial effect of Ag^(+)and Cl^(-).Sample AgCl@SiO_(2)/CTS‑Cl with a dosage of 640.00μg·mL^(-1) could completely kill the two kinds of tested bacteria in 12 h of incubation;it retains a high antibacterial efficiency even after 10 cycles of antibacterial tests.展开更多
This study investigates the microstructure and co-precipitation behavior of multicomponent(Ni(Al,Mn)and Cu)nanoparticles in the weld heat-affected zones of high-strength low-carbon steel.Through thermal simulations,th...This study investigates the microstructure and co-precipitation behavior of multicomponent(Ni(Al,Mn)and Cu)nanoparticles in the weld heat-affected zones of high-strength low-carbon steel.Through thermal simulations,the intercritical,fine-grained,and coarsegrained heat-affected zones were systematically characterized to elucidate the interplay between the microstructure,precipitation,and mechanical properties.At a heat input of 30 kJ·cm^(−1),Ni(Al,Mn)nanoparticles dissolve in the intercritical heat-affected zone,followed by dense reprecipitation coupled with significant coarsening of Cu particles during cooling,thereby retaining high strength but reducing impact toughness to(142±10)J(compared to(205±8)J of the base metal).The fine-grained heat-affected zone,under the same heat input,exhibits a refined ferritic-bainite matrix with a few fine Ni(Al,Mn)and slightly coarsened Cu particles,thus enhancing plastic deformation capacity and resulting in superior impact toughness of(196±7)J.Despite complete dissolution of original precipitates at peak temperatures in the coarse-grained heat-affected zone,re-precipitated nanoparticles provide effective strengthening effect,compensating for grain coarsening and dislocation recovery and resulting in an impressive impact toughness of(186±6)J.The toughening mechanism is primarily attributed to the synergistic actions of the matrix,precipitates,and deformation twins.These findings provide mechanistic and quantitative insights for developing processing-microstructure-property relationships in different welding heat-affected zones,and this framework can be further utilized to optimize welding parameters for tailored applications.展开更多
Rechargeable Zn/Sn-air batteries have received considerable attention as promising energy storage devices.However,the electrochemical performance of these batteries is significantly constrained by the sluggish electro...Rechargeable Zn/Sn-air batteries have received considerable attention as promising energy storage devices.However,the electrochemical performance of these batteries is significantly constrained by the sluggish electrocatalytic reaction kinetics at the cathode.The integration of light energy into Zn/Sn-air batteries is a promising strategy for enhancing their performance.However,the photothermal and photoelectric effects generate heat in the battery under prolonged solar irradiation,leading to air cathode instability.This paper presents the first design and synthesis of Ni_(2)-1,5-diamino-4,8-dihydroxyanthraquinone(Ni_(2)DDA),an electronically conductiveπ-d conjugated metal-organic framework(MOF).Ni_(2)DDA exhibits both photoelectric and photothermal effects,with an optical band gap of~1.14 eV.Under illumination,Ni_(2)DDA achieves excellent oxygen evolution reaction performance(with an overpotential of 245 mV vs.reversible hydrogen electrode at 10 mA cm^(−2))and photothermal stability.These properties result from the synergy between the photoelectric and photothermal effects of Ni_(2)DDA.Upon integration into Zn/Sn-air batteries,Ni_(2)DDA ensures excellent cycling stability under light and exhibits remarkable performance in high-temperature environments up to 80℃.This study experimentally confirms the stable operation of photo-assisted Zn/Sn-air batteries under high-temperature conditions for the first time and provides novel insights into the application of electronically conductive MOFs in photoelectrocatalysis and photothermal catalysis.展开更多
The Almus Fault Zone(AFZ)is one of the major splay faults of the North Anatolian Fault Zone(NAFZ)and is important for understanding its tectonic features and assessing regional seismic hazards.This research presents t...The Almus Fault Zone(AFZ)is one of the major splay faults of the North Anatolian Fault Zone(NAFZ)and is important for understanding its tectonic features and assessing regional seismic hazards.This research presents the integration of morphometric indices to quantitatively assess the spatial variation of tectonic activity along the AFZ.The AFZ is an active fault with both strike-slip and normal fault components and consists of two main branches,Mercimekdağı-Çamdere Fault(MÇF)and Tokat Fault(TF)segments.This study aims to assess the relative tectonic activity of the AFZ using various morphometric indices,based on a 10 m resolution DEM,with the aid of ArcGIS and MATLAB software.For this purpose,morphometric indices such as hypsometric integral(HI:0.35-0.65),mountain front sinuosity(Smf:1.3-1.44),valley floor width-height ratio(Vf:0.15-2.28),asymmetry factor(AF:23-77),drainage basin shape(Bs:1.13-6.10)and normalized steepness index(ksn:1-498)were applied to 53 drainage basins.When the Smf and mean Vf indices results were evaluated,it was calculated that the uplift ratio of the region was more than 0.5 mm/yr.The spatial distribution of the relative tectonic activity(Iat)of the area was revealed by combining the obtained morphometric indices analysis results.According to the Iat result,it was concluded that the MercimekdağıÇamdere Fault and Tokat Fault segments have high tectonic activity,but the Mercimekdağı-Çamdere Fault segment has higher tectonic activity.The results obtained were also confirmed by field observations.This research provides valuable information for the evaluation of tectonic activity in drainage systems controlled by splay faults.展开更多
The Guanxian-Anxian fault zone in the Longmen Shan,Sichuan,China,exhibits long-term creep-slip but ruptured during the 2008 Wenchuan earthquake,challenging the view that creeping faults rarely generate strong earthqua...The Guanxian-Anxian fault zone in the Longmen Shan,Sichuan,China,exhibits long-term creep-slip but ruptured during the 2008 Wenchuan earthquake,challenging the view that creeping faults rarely generate strong earthquakes.To investigate the transition from creep-slip to stick-slip,we analyzed fault rocks from the WFSD-3,using microstructural observations,XRD,μXRF,Raman spectroscopy,and quartz grain size statistics.Fault rocks show intense foliation,pressure-solution structures,and abundant clay minerals,reflecting long-term aseismic creep.At the interface between black and gray fault gouges at~1249.98 m,microstructures indicate stick-slip behavior,including truncated grains,angular fragments,and finer grain sizes.Here,clay content drops sharply while strong minerals(quartz,feldspar,calcite,dolomite)increase.Elemental mapping shows Al and K enriched in black gouge,whereas Ca and Si in gray gouge;Raman spectroscopy indicates possible graphitization;the finest quartz grains occur in black gouge.These features mark co-seismic principal slip zone of the Wenchuan earthquake.We propose that fluid-driven transformation of strong minerals into clays facilitates creep-slip,whereas localized precipitation of strong minerals strengthens the fault,causing stress accumulation and controlling the creep-slip to stick-slip transition.This mechanism has implications for reassessing seismic hazards of creeping faults.展开更多
An innovative real-time monitoring method for surrounding rock damage based on microseismic time-lapse double-difference tomography is proposed for delayed dynamic damage identification and insufficient detection of a...An innovative real-time monitoring method for surrounding rock damage based on microseismic time-lapse double-difference tomography is proposed for delayed dynamic damage identification and insufficient detection of adverse geological conditions in deep-buried tunnel construction.The installation techniques for microseismic sensors were optimized by mounting sensors at bolt ends which significantly improves signal-to-noise ratio(SNR)and anti-interference capability compared to conventional borehole placement.Subsequently,a 3D wave velocity evolution model that incorporates construction-induced disturbances was established,enabling the first visualization of spatiotemporal variations in surrounding rock wave velocity.It finds significant wave velocity reduction near the tunnel face,with roof and floor damage zones extending 40–50 m;wave velocities approaching undisturbed levels at 15 m ahead of the working face and on the laterally undisturbed side;pronounced spatial asymmetry in wave velocity distribution—values on the left side exceed those on the right,with a clear stress concentration or transition zone located 10–15 m;and systematically lower velocities behind the face than in front,indicating asymmetric rock damage development.These results provide essential theoretical support and practical guidance for optimizing dynamic construction strategies,enabling real-time adjustment of support parameters,and establishing safety early warning systems in deep-buried tunnel engineering.展开更多
基金National Natural Science Foundation of China,No.42471455,No.42230113National Key Research and Development Program of China,No.2022YFC3800804-01。
文摘Ensuring national food security amidst rapid population growth and increasing extreme weather events remains a critical global challenge.However,the extent to which agricultural modernization in China enhances grain yield and contributes to food security remains unclear.Therefore,using panel data from 327 Chinese cities(2013–2021),this study employs spatial econometric models to analyze the spatial spillover effects of agricultural modernization level(AML)on grain yield and to reveal regional heterogeneity across nine major agricultural zones.The results showed a cumulative grain yield increase of 23.7 million tons,with peak productivity concentrated along the Hu Line and declining eastward and westward.AML also exhibited a steady increase but a clear spatial gradient,decreasing from coastal to inland regions,with the highest level observed in Southern China(SC).A key finding was that a 1%increase in AML directly raised local grain yield by an average of 4.185%,accompanied by significant positive spillover effects on neighboring regions.Regional variations revealed distinct patterns:the direct effects of AML were more pronounced in southern and eastern zones,while spillover effects dominated in northern and western zones.The largest positive direct impact of AML on grain yield was observed in the SC(8.499%),while Middle-Lower Yangtze Plain ranked second but exhibited the strongest positive spatial spillover effect(4.534%).These findings highlight the critical role of agricultural modernization in promoting grain production and provide a solid basis for optimizing regional agricultural systems,ensuring food security,and advancing sustainable agriculture.
文摘Root-zone temperature(RZT)strongly affects plant growth,nutrient uptake and tolerance to environmental stress,making its regulation a key challenge in greenhouse cultivation in cold climates.This study aimed to assess the potential of passive techniques,namely black polyethylene mulch and row covers,for modifying RZT dynamics in lettuce(Lactuca sativa L.)production and to evaluate the predictive performance of the eXtreme Gradient Boosting(XGBoost)algorithm.Experiments were conducted in Iğdır,Türkiye,over a 61-day period,with soil temperature continuously monitored at depths of 1-30 cm under mulched and non-mulched conditions,alongside measurements of greenhouse air temperature both with and without row covers.The application of row covers increased internal air temperature by 5.8℃,while mulching raised RZT by 0.6-1.3℃,with effects diminishing at deeper layers.XGBoost modeling achieved high predictive accuracy,with RMSE values of 0.150-0.189◦C and R^(2)values above 0.99,and feature-importance analysis indicated that neighboring soil depths were the strongest predictors of RZT.These findings show that integrating row covers and mulching can stabilize the root-zone microclimate without active heating.The XGBoost model provides a robust tool for forecasting soil temperature and supports sustainable greenhouse production in cold regions.
文摘AIM:To investigate the impact of preoperative anterior corneal topographic parameters on the morphology of the postoperative effective optical zone(EOZ)in patients undergoing keratorefractive lenticule extraction(KLEx)and wavefront-guided LASIK(WG-LASIK).METHODS:This retrospective study included 310 eyes from patients who underwent either KLEx(via small incision lenticule extraction,171 eyes)or WG-LASIK(139 eyes).Patients were stratified into subgroups based on the median values of spherical equivalent(SE)and anterior corneal topographic parameters.Postoperative EOZ parameters were measured 1mo after surgery and compared across subgroups.Correlation analysis and multivariable linear regression analysis were performed to explore the associations between preoperative anterior corneal topographic parameters and EOZ parameters.RESULTS:A total of 310 eyes were included(KLEx:171 eyes from 88 patients;WG-LASIK:139 eyes from 82 patients).The mean age was 30.65±5.67y in the KLEx cohort and 29.06±5.94y in the WG-LASIK cohort.In the KLEx cohort,SE,preoperative mean keratometry(Km),steep keratometry(K2),and anterior corneal astigmatism(K2-K1)were positively correlated with the postoperative optical zone reduction ratio(RR=EOZ/planned optical zone×100%;all P<0.01).Multivariable regression identified SE[β=0.027,95%confidence interval(CI):0.022-0.032,P<0.001],Km(β=0.009,95%CI:0.002-0.016,P=0.014),and anterior corneal astigmatism(β=0.031,95%CI:0.013-0.049,P<0.001)as significant predictors of RR(R²=0.456,P<0.001).In the WG-LASIK cohort,SE was positively correlated with RR(P<0.01);K2 and anterior corneal astigmatism were positively correlated with both RR(P<0.05)and EOZ eccentricity(P<0.01).Multivariable regression showed SE(β=0.015,95%CI:0.007-0.023,P<0.001)and anterior corneal astigmatism(β=0.029,95%CI:0.012-0.047,P=0.001)were significant predictors of RR(R²=0.121,P<0.001).CONCLUSION:Preoperative anterior corneal topographic parameters,particularly anterior corneal astigmatism,significantly affect postoperative EOZ morphology in both KLEx and WG-LASIK.Additionally,Km is a predictor of EOZ reduction specifically in KLEx.
基金supported by the Major Program of the National Natural Science Foundation of China (Grant No.42090055)the National Major Scientific Instruments and Equipment Development Projects of China (Grant No.41827808)the National Nature Science Foundation of China (Grant No.42207216).
文摘The strength of the sliding zone soil determines the stability of reservoir landslides.Fluctuations in water levels cause a change in the seepage field,which serves as both the external hydrogeological environment and the internal component of a landslide.Therefore,considering the strength changes of the sliding zone with seepage effects,they correspond with the actual hydrogeological circumstances.To investigate the shear behavior of sliding zone soil under various seepage pressures,24 samples were conducted by a self-developed apparatus to observe the shear strength and measure the permeability coefficients at different deformation stages.After seepage-shear tests,the composition of clay minerals and microscopic structure on the shear surface were analyzed through X-ray and scanning electron microscope(SEM)to understand the coupling effects of seepage on strength.The results revealed that the sliding zone soil exhibited strain-hardening without seepage pressure.However,the introduction of seepage caused a significant reduction in shear strength,resulting in strain-softening characterized by a three-stage process.Long-term seepage action softened clay particles and transported broken particles into effective seepage channels,causing continuous damage to the interior structure and reducing the permeability coefficient.Increased seepage pressure decreased the peak strength by disrupting occlusal and frictional forces between sliding zone soil particles,which carried away more clay particles,contributing to an overhead structure in the soil that raised the permeability coefficient and decreased residual strength.The internal friction angle was less sensitive to variations in seepage pressure than cohesion.
基金support from the National Natural Science Foundation of China (No. U1960202)the Opening Foundation from Shanghai Engineering Research Center of Hot Manufacturing, China (No. 18DZ2253400)。
文摘This work focuses on the influence of Al content on the precipitation of nanoprecipitates,growth of prior austenite grains(PAGs),and impact toughness in simulated coarse-grained heat-affected zones (CGHAZs) of two experimental shipbuilding steels after being subjected to high-heat input welding at 400 kJ·cm^(-1).The base metals (BMs) of both steels contained three types of precipitates Type Ⅰ:cubic (Ti,Nb)(C,N),Type Ⅱ:precipitate with cubic (Ti,Nb)(C,N) core and Nb-rich cap,and Type Ⅲ:ellipsoidal Nb-rich precipitate.In the BM of 60Al and 160Al steels,the number densities of the precipitates were 11.37×10^(5) and 13.88×10^(5) mm^(-2),respectively The 60Al and 160Al steel contained 38.12% and 6.39% Type Ⅲ precipitates,respectively.The difference in the content of Type Ⅲ precipitates in the 60Al steel reduced the pinning effect at the elevated temperature of the CGHAZ,which facilitated the growth of PAGs The average PAG sizes in the CGHAZ of the 60Al and 160Al steels were 189.73 and 174.7μm,respectively.In the 60Al steel,the low lattice mismatch among Cu_(2)S,TiN,and γ-Al_(2)O_(3)facilitated the precipitation of Cu_(2)S and TiN onto γ-Al_(2)O_(3)during welding,which decreased the number density of independently precipitated (Ti,Nb)(C,N) particles but increased that of γ-Al_(2)O_(3)–Ti N–Cu_(2)S particles.Thus abnormally large PAGs formed in the CGHAZ of the 60Al steel,and they reached a maximum size of 1 mm.These PAGs greatly reduced the microstructural homogeneity and consequently decreased the impact toughness from 134 (0.016wt%Al) to 54 J (0.006wt%Al)at-40℃.
基金supported by the Key Project of the National Natural Science Foundation of China(U23B2091)the National Key R&D Program of China(2022YFC2905600)+1 种基金the Youth Project of the National Natural Science Foundation of China(52304104 and 52404157)the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(GZB20240825).
文摘As the mine depth around the world increases,the temperature of the surrounding rock of the mining workface increases significantly.To control the heat hazards,the hot water in the mining floor is developed during mining to decrease the min-ing workface temperature while also developing geothermal energy.This method is called the co-exploitation of mine and geothermal energy(CMGE).The geothermal development may precipitate the large-scale failure of the nearby fault zone during the mining process.However,the evolution of shear slide and shear failure of fault under geothermal production/rein-jection during mining is missing.Therefore,a fully-coupled hydraulic mechanism(HM)double-medium model for CMGE was developed based on the measured data of the Chensilou mine.A comparative analysis of the mechanical response of fault between CMGE and single mining was conducted.The disturbance of geothermal production pressure and reinjection pressure under mining on fault stability were respectively expounded.The results indicate that:(1)The disturbance of geo-thermal reinjection amplifies the disturbance of mining on fault stability.The amplified effect resulted in a normal stress drop of the fault,further leading to a substantial increase in shear slide distance,failure area,and cumulative seismic moment of fault compared with the single mining process.(2)As the distance of reinjection well to the fault decreases,the fault failure intensity increases.Setting the production well within the fault is advantageous for controlling fault stability under CMGE.(3)The essence of the combined disturbance of CMGE on the nearby fault is the overlay of tensile stress disturbance on the fault rock mass of the mining and geothermal reinjection.Though the geothermal reinjection causes a minor normal stress drop of fault,it can result in a more serious fault failure under CMGE.This paper supplies a significant gap in understanding thenearby faults failure under CMGE.
文摘AIM:To observe the effect of the plus power ring zone(PPRZ)area and distribution on myopia progression.METHODS:This retrospective study enrolled 137 pre-teens aged 8-12 at Taiyuan Aier Eye Hospital between 2019 and 2021.They were fitted with Ortho-K lenses for the first time due to refractive error,with a one-year follow-up period.To indicate the peripheral plus ring zone overlapping with the pupil zone(PPROPZ)accompanying PPRZ,participants were divided based on the PPROPZ to PPRZ ratio.The experimental group had 103 eyes with a PPROPZ to PPRZ ratio of≥0.2,and the control group had 103 eyes with a ratio of<0.2.Participants had a spherical diopter in the range of-6.00 D to-0.75 D,against-the-rule astigmatism less than 1.00 D,with-the-rule astigmatism less than 1.50 D,and corneal curvatures of 39.00 D to 46.00 D.They had a stable best corrected visual acuity of 0.10 LogMAR(20/25)or better when wearing orthokeratology(Ortho-K)lenses.PPRZ and PPROPZ were measured using ImageJ;corneal topography assessed corneal-related parameters,and an optical biometer measured the axial length of the eyes pre and post-one years of lens wear.RESULTS:Changes in axial length elongation were found to decrease when either the PPRZ(P<0.01)or PPROPZ(P<0.001)was increased significantly.The axial length growth was faster in the control group(0.37±0.2 mm)than in the experimental group(0.21±0.11 mm).Furthermore,we found that a larger horizontal visible iris diameter(HVID)corresponded to slower axial growth of the eye.In contrast,axial length growth showed no correlation with surface regularity index(SRI),surface asymmetry index(SAI),flat keratometry value(K_(f)),steep keratometry value(K_(s)).CONCLUSION:For orthokeratology,wearers with larger PPROPZ to PPRZ ratio usually experiences a reduction in axial length growth.The PPRZ and PPROPZ are negatively correlated with the axial length.Our findings provide a recommendation and methods for studying the myopia control mechanism through Ortho-K lenses.
基金fund support was received from National Social Science Fund of China[Grant No.23BJL010].
文摘Exploring the specific environmental impacts and mechanisms of China’s sustainable development pilot policy can enrich and expand China’s institutional and practical experiences,offering valuable insights and references for advancing global environmental sustainability.This study selects the National Innovation Demonstration Zone for Sustainable Development Agenda(NIDZSDA)as the sample and empirically evaluates the effects of the policy on urban environmental quality,using panel data from 74 prefecture-level cities in China between 2006 and 2020.The findings indicate that the sustainable development policy significantly improves urban environmental quality.Two key mechanisms identified are the aggregation of high-quality talent and the enhancement of technological innovation capabilities.Furthermore,the policy exhibits heterogeneous effects across different types of cities,with more pronounced improvements observed in mega and super cities,as well as in resource-based cities.
文摘Herein,3‑aminopropyltriethoxysilane(APTES)was used to modify F‑containing silica slag(SS)by simple grafting and served as a multifunctional barrier layer.The amino group(—NH2)in the amino‑modified SS(NH2‑SS)forms ligand bonds or hydrogen bonds with sulfur ions in lithium polysulfides(LiPSs),thus inhibiting the shuttle effect.Electrochemical analyses demonstrated that lithium‑sulfur(Li‑S)batteries employing the NH2‑SS interlayer exhibited discharge specific capacities of 1048 and 789 mAh·g^(-1) at 0.2C and 2C,respectively,and even at 4C,the initial discharge specific capacity remained at 590 mAh·g^(-1),outperforming the Li‑S battery with unmodified SS as the interlayer.
基金Supported by the Key projects of the PetroChina Joint Fund Under the National Natural Science Foundation of China(U23B20154,92255302)Science and Technology Cooperation Project of the Innovation Consortium between PetroChina and Southwest Petroleum University(2020CX010000)Open Fund of the Key Laboratory of Carbonate Reservoirs,China National Petroleum Corporation(RIPED-2024-JS-1804).
文摘This study reconstructed the paleo-uplift and depression pattern within the sequence stratigraphic framework of the Mid-Permian Maokou Formation,Sichuan Basin,investigated its tectono-sedimentary mechanisms and its control on paleogeomorphology and large-sale shoals based on analysis of outcrops,loggings and seismic data.The results show that the Maokou Formation comprises two third-order sequences,six fourth-order sequences(SSQ1-SSQ6),and four distinct slope-break zones developing progressively from north to south.Slope-break zones I-III in the northern basin,controlled by synsedimentary extensional faults,exhibited a NE-trending linear distribution with gradual southeastward migration.In contrast,slope-break zone IV in the southern basin displayed an arcuate distribution along the Emeishan Large Igneous Province(ELIP).The evolutions of these multistage slope-break zones governed the Mid-Permian paleogeomorphy in the Sichuan Basin transformations from a giant,north-dipping gentle slope(higher in the southwest than in the northeast)in the early-stage(SSQ1-SSQ2)to a platform(south)-basin(north)pattern in the middle-stage(SSQ3-SSQ5).Ultimately,a further depression zone developed in the southwestern basin during the late-stage(SSQ6),forming a paleo-uplift bounded by two depressions.The developments of the Mid-Permian paleogeomorphic configuration reflected the combined control by the rapid subduction of the Mianlüe Ocean and the episodic eruptions of the Emeishan mantle plume(or hot spots),which jointly facilitated the formation of extensive high-energy shoal facies belts along slope-break zones and around paleo-volcanic uplifts.
基金financial support from the National Key Research and Development Program of China(No.2023YFC2907904)the National Natural Science Foundation of China(Nos.52374364,52104355,52074363)+1 种基金National Sustainable Development Agenda Innovation Demonstration Zones:Provincial Special“Open Competition”Project in Chenzhou,China(No.2022sfq57)Postdoctoral Innovation Talent Support Program,China(No.BX20230438)。
文摘The effect of temperature on molten zone length was investigated through simulation to optimize the control of molten zone length during the experimental process. The temperature gradient distribution within the molten zone during zone refining was simulated using COMSOL Multiphysics software and experimentally validated. The simulated molten zone length showed good agreement with the actual measured length. The experimental study of tellurium purification by zone refining was conducted under the following conditions: three passes of zone refining, a hydrogen flow rate of 0.5 L/min, and molten zone movement speeds of 0.5 and 1.0 mm/min. The results demonstrated that the removal efficiencies of impurities such as Ca and Cu exceeded 95%, while the removal efficiency of phosphorus (P) reached over 70%. And the purity of tellurium reached 6N.
基金funded through project NUBOLOSYTI (PID2023149972NB-100) of the Spanish Ministry of Science and Innovation (MICINN)supported by an IFUdG 2022 fellowship。
文摘The interactions between clouds and aerosols represent one of the largest uncertainties in assessing the Earth's radiation budget, highlighting the importance of research on the transition zone(TZ) within the cloud-aerosol continuum.This study assesses the global distribution of TZ conditions, analyzes its optical characteristics, and determines the cloud or aerosol types most commonly associated with them, using the cloud-aerosol discrimination(CAD) score of the CloudAerosol Lidar with Orthogonal Polarization(CALIOP) instrument on the CALIPSO satellite. The CAD score classifies clouds and aerosols by the probability density functions of attenuated backscatter, total color ratio, volume depolarization ratio, altitude, and latitude. After applying several filters to avoid artifacts, the TZ was identified as those atmospheric layers that cannot be clearly classified as clouds or aerosols, layers within the no-confidence range(NCR) of the CAD score, and cirrus fringes. The optical characteristics of NCR layers exhibit two main clusters: Cluster 1, with properties between high-altitude ice clouds and aerosols(e.g., wispy cloud fragments), and Cluster 2, with properties between water clouds and aerosols at lower altitudes(e.g., large hydrated aerosols). Our results highlight the significant ubiquity of TZ conditions, which appear in 9.5% of all profiles and comprise 6.4% of the detected layers. Cluster 1 and cirrus-fringe layers predominate near the ITCZ and in mid-latitudes, whereas Cluster 2 layers are more frequent over the oceans along the central West African and East Asian coasts, where elevated smoke and dusty marine aerosols are common.
基金National Natural Science Foundation of China(11875039)Shanxi Scholarship Council of China(2023-033)+2 种基金Fundamental Research Program of Shanxi Province(202303021221071)China Baowu Low Carbon Metallurgical Innovation Foundation(2022)2023 Anhui Major Industrial Innovation Plan Project。
文摘The in-flight heating process of cerium dioxide(CeO_(2))powders was investigated through experiments and numerical simulations.In the experiment,CeO_(2)powder(average size of 30μm)was injected into radio-frequency(RF)argon plasma,and the temperatures were measured using a DPV-2000 monitor.A model combining the electromagnetism,thermal flow,and heat transfer characteristics of powder during in-flight heating in argon plasma was proposed.The melting processes of CeO_(2)powders of different diameters,with and without thermal resistance effect,were investigated.Results show that the heating process of CeO_(2)powder particles consists of three main stages,one of which is relevant to a dimensionless parameter known as the Biot number.When the Biot value≥0.1,thermal resistance increases significantly,especially for the larger powders.The predicted temperature of the particles at the outlet(1800–2880 K)is in good agreement with the experimental result.
文摘To ensure the efficient use of resources,particularly in water-scarce arid and semi-arid regions where abiotic stress threatens food security,assessing soil and climate suitability for specific crops is crucial.Simultaneously,food production must align with sustainable development goals by minimizing negative environmental impacts.Therefore,establishing agro-climatic suitability using a spatiotemporal approach is essential.This involves three key steps:first,determining the climatically appropriate months based on the species’requirements(temporal suitability),and second,establishing the soil suitability of specific plots(spatial suitability).Following this,quantifying crop evapotranspiration allows for optimized water use.This study used climatic and soil variables from diverse data sources to characterize the study area.Subsequently,suitability classes for Portulaca oleracea were determined based on existing literature.Our analysis concerning temporal suitability revealed that June and July are the optimal months for sowing this species in all of the municipalities.Spatially,approximately 30%of the agricultural land use of the study area exhibits a highly suitable class in most municipalities.Both dimensions,the temporal and the spatially,were validated through Chi square(χ^(2))Goodness-of-Fit test and theχ^(2)test of independence,respectively.Consequently,for a one-month production cycle during periods of high suitability,estimated evapotranspiration values are between 210 and 245 mm.In brief,the study area demonstrates favorable agro-climatic conditions for P.oleracea cultivation in specific months of the year according to parameters used,with potential in a large proportion of agricultural land and achievable water requirements.
文摘Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticles were chlorinated by NaClO solution to get AgCl@SiO_(2)/CTS‑based chloramine nano‑hybrid materials,denoted as AgCl@SiO_(2)/CTS‑Cl.A transmission electron microscope was used to observe the morphology of the as‑prepared samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.At the same time,an X‑ray diffractometer and an infrared spectroscope were utilized to characterize their crystal and chemical structures.Besides,ζpotentials were measured to elucidate the surface modification of AgCl nanoparticles by—NH_(2),the antibacterial mechanism of AgCl@SiO_(2)/CTS‑Cl was investigated by scanning electron microscopy,and Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were used as the to‑be‑tested strains to evaluate the antimicrobial activity of samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.Findings demonstrate that sample AgCl@SiO_(2)/CTS exhibits a chain‑like structure ascribed to the interaction between—NH_(2),and each AgCl@SiO_(2)/CTS hybrid nanoparticle contains several AgCl cores.In the meantime,sample AgCl@SiO_(2)/CTS‑Cl exhibits excellent antibacterial activity against E.coli and S.aureus,which is attributed to the synergistic antibacterial effect of Ag^(+)and Cl^(-).Sample AgCl@SiO_(2)/CTS‑Cl with a dosage of 640.00μg·mL^(-1) could completely kill the two kinds of tested bacteria in 12 h of incubation;it retains a high antibacterial efficiency even after 10 cycles of antibacterial tests.
基金supported by the National Natural Science Foundation of China(No.U2330110)Youth Science Foundation Project(Category A)of Liaoning Province,China(No.2025JH6/101100006).
文摘This study investigates the microstructure and co-precipitation behavior of multicomponent(Ni(Al,Mn)and Cu)nanoparticles in the weld heat-affected zones of high-strength low-carbon steel.Through thermal simulations,the intercritical,fine-grained,and coarsegrained heat-affected zones were systematically characterized to elucidate the interplay between the microstructure,precipitation,and mechanical properties.At a heat input of 30 kJ·cm^(−1),Ni(Al,Mn)nanoparticles dissolve in the intercritical heat-affected zone,followed by dense reprecipitation coupled with significant coarsening of Cu particles during cooling,thereby retaining high strength but reducing impact toughness to(142±10)J(compared to(205±8)J of the base metal).The fine-grained heat-affected zone,under the same heat input,exhibits a refined ferritic-bainite matrix with a few fine Ni(Al,Mn)and slightly coarsened Cu particles,thus enhancing plastic deformation capacity and resulting in superior impact toughness of(196±7)J.Despite complete dissolution of original precipitates at peak temperatures in the coarse-grained heat-affected zone,re-precipitated nanoparticles provide effective strengthening effect,compensating for grain coarsening and dislocation recovery and resulting in an impressive impact toughness of(186±6)J.The toughening mechanism is primarily attributed to the synergistic actions of the matrix,precipitates,and deformation twins.These findings provide mechanistic and quantitative insights for developing processing-microstructure-property relationships in different welding heat-affected zones,and this framework can be further utilized to optimize welding parameters for tailored applications.
基金supported by the National Natural Science Foundation of China(No.62464010)Spring City Plan-Special Program for Young Talents(K202005007)+2 种基金Yunnan Talents Support Plan for Young Talents(XDYC-QNRC-2022-0482)Yunnan Local Colleges Applied Basic Research Projects(202101BA070001-138)Frontier Research Team of Kunming University 2023.
文摘Rechargeable Zn/Sn-air batteries have received considerable attention as promising energy storage devices.However,the electrochemical performance of these batteries is significantly constrained by the sluggish electrocatalytic reaction kinetics at the cathode.The integration of light energy into Zn/Sn-air batteries is a promising strategy for enhancing their performance.However,the photothermal and photoelectric effects generate heat in the battery under prolonged solar irradiation,leading to air cathode instability.This paper presents the first design and synthesis of Ni_(2)-1,5-diamino-4,8-dihydroxyanthraquinone(Ni_(2)DDA),an electronically conductiveπ-d conjugated metal-organic framework(MOF).Ni_(2)DDA exhibits both photoelectric and photothermal effects,with an optical band gap of~1.14 eV.Under illumination,Ni_(2)DDA achieves excellent oxygen evolution reaction performance(with an overpotential of 245 mV vs.reversible hydrogen electrode at 10 mA cm^(−2))and photothermal stability.These properties result from the synergy between the photoelectric and photothermal effects of Ni_(2)DDA.Upon integration into Zn/Sn-air batteries,Ni_(2)DDA ensures excellent cycling stability under light and exhibits remarkable performance in high-temperature environments up to 80℃.This study experimentally confirms the stable operation of photo-assisted Zn/Sn-air batteries under high-temperature conditions for the first time and provides novel insights into the application of electronically conductive MOFs in photoelectrocatalysis and photothermal catalysis.
文摘The Almus Fault Zone(AFZ)is one of the major splay faults of the North Anatolian Fault Zone(NAFZ)and is important for understanding its tectonic features and assessing regional seismic hazards.This research presents the integration of morphometric indices to quantitatively assess the spatial variation of tectonic activity along the AFZ.The AFZ is an active fault with both strike-slip and normal fault components and consists of two main branches,Mercimekdağı-Çamdere Fault(MÇF)and Tokat Fault(TF)segments.This study aims to assess the relative tectonic activity of the AFZ using various morphometric indices,based on a 10 m resolution DEM,with the aid of ArcGIS and MATLAB software.For this purpose,morphometric indices such as hypsometric integral(HI:0.35-0.65),mountain front sinuosity(Smf:1.3-1.44),valley floor width-height ratio(Vf:0.15-2.28),asymmetry factor(AF:23-77),drainage basin shape(Bs:1.13-6.10)and normalized steepness index(ksn:1-498)were applied to 53 drainage basins.When the Smf and mean Vf indices results were evaluated,it was calculated that the uplift ratio of the region was more than 0.5 mm/yr.The spatial distribution of the relative tectonic activity(Iat)of the area was revealed by combining the obtained morphometric indices analysis results.According to the Iat result,it was concluded that the MercimekdağıÇamdere Fault and Tokat Fault segments have high tectonic activity,but the Mercimekdağı-Çamdere Fault segment has higher tectonic activity.The results obtained were also confirmed by field observations.This research provides valuable information for the evaluation of tectonic activity in drainage systems controlled by splay faults.
基金supported by the National Natural Science Foundation of China(42230312,42272270,42172262,42372266)the Deep Earth Probe and Mineral Resources Exploration-National Science and Technology Major Project(2024ZD1000500)the China Geological Survey Project(DD20240041).
文摘The Guanxian-Anxian fault zone in the Longmen Shan,Sichuan,China,exhibits long-term creep-slip but ruptured during the 2008 Wenchuan earthquake,challenging the view that creeping faults rarely generate strong earthquakes.To investigate the transition from creep-slip to stick-slip,we analyzed fault rocks from the WFSD-3,using microstructural observations,XRD,μXRF,Raman spectroscopy,and quartz grain size statistics.Fault rocks show intense foliation,pressure-solution structures,and abundant clay minerals,reflecting long-term aseismic creep.At the interface between black and gray fault gouges at~1249.98 m,microstructures indicate stick-slip behavior,including truncated grains,angular fragments,and finer grain sizes.Here,clay content drops sharply while strong minerals(quartz,feldspar,calcite,dolomite)increase.Elemental mapping shows Al and K enriched in black gouge,whereas Ca and Si in gray gouge;Raman spectroscopy indicates possible graphitization;the finest quartz grains occur in black gouge.These features mark co-seismic principal slip zone of the Wenchuan earthquake.We propose that fluid-driven transformation of strong minerals into clays facilitates creep-slip,whereas localized precipitation of strong minerals strengthens the fault,causing stress accumulation and controlling the creep-slip to stick-slip transition.This mechanism has implications for reassessing seismic hazards of creeping faults.
基金support of the National Natural Science Foundation of China(No.52274176)the Guangdong Province Key Areas R&D Program(No.2022B0101070001)+5 种基金Chongqing Elite Innovation and Entrepreneurship Leading talent Project(No.CQYC20220302517)the Chongqing Natural Science Foundation Innovation and Development Joint Fund(No.CSTB2022NSCQ-LZX0079)the National Key Research and Development Program Young Scientists Project(No.2022YFC2905700)the Chongqing Municipal Education Commission“Shuangcheng Economic Circle Construction in Chengdu-Chongqing Area”Science and Technology Innovation Project(No.KJCX2020031)the Fundamental Research Funds for the Central Universities(No.2024CDJGF-009)the Key Project for Technological Innovation and Application Development in Chongqing(No.CSTB2025TIAD-KPX0029).
文摘An innovative real-time monitoring method for surrounding rock damage based on microseismic time-lapse double-difference tomography is proposed for delayed dynamic damage identification and insufficient detection of adverse geological conditions in deep-buried tunnel construction.The installation techniques for microseismic sensors were optimized by mounting sensors at bolt ends which significantly improves signal-to-noise ratio(SNR)and anti-interference capability compared to conventional borehole placement.Subsequently,a 3D wave velocity evolution model that incorporates construction-induced disturbances was established,enabling the first visualization of spatiotemporal variations in surrounding rock wave velocity.It finds significant wave velocity reduction near the tunnel face,with roof and floor damage zones extending 40–50 m;wave velocities approaching undisturbed levels at 15 m ahead of the working face and on the laterally undisturbed side;pronounced spatial asymmetry in wave velocity distribution—values on the left side exceed those on the right,with a clear stress concentration or transition zone located 10–15 m;and systematically lower velocities behind the face than in front,indicating asymmetric rock damage development.These results provide essential theoretical support and practical guidance for optimizing dynamic construction strategies,enabling real-time adjustment of support parameters,and establishing safety early warning systems in deep-buried tunnel engineering.