Strategies for achieving high-energy-density lithium-ion batteries include using high-capacity materials such as high-nickel NCM,increasing the active material content in the electrode by utilizing high-conductivity c...Strategies for achieving high-energy-density lithium-ion batteries include using high-capacity materials such as high-nickel NCM,increasing the active material content in the electrode by utilizing high-conductivity carbon nanotubes(CNT)conductive materials,and electrode thickening.However,these methods are still limited due to the limitation in the capacity of high-nickel NCM,aggregation of CNT conductive materials,and nonuniform material distribution of thick-film electrodes,which ultimately damage the mechanical and electrical integrity of the electrode,leading to a decrease in electrochemical performance.Here,we present an integrated binder-CNT composite dispersion solution to realize a high-solids-content(>77 wt%)slurry for high-mass-loading electrodes and to mitigate the migration of binder and conductive additives.Indeed,the approach reduces solvent usage by approximately 30%and ensures uniform conductive additive-binder domain distribution during electrode manufacturing,resulting in improved coating quality and adhesive strength for high-mass-loading electrodes(>12 mAh cm^(−2)).In terms of various electrode properties,the presented electrode showed low resistance and excellent electrochemical properties despite the low CNT contents of 0.6 wt%compared to the pristine-applied electrode with 0.85 wt%CNT contents.Moreover,our strategy enables faster drying,which increases the coating speed,thereby offering potential energy savings and supporting carbon neutrality in wet-based electrode manufacturing processes.展开更多
One-dimensional ensemble dispersion entropy(EDE1D)is an effective nonlinear dynamic analysis method for complexity measurement of time series.However,it is only restricted to assessing the complexity of one-di-mension...One-dimensional ensemble dispersion entropy(EDE1D)is an effective nonlinear dynamic analysis method for complexity measurement of time series.However,it is only restricted to assessing the complexity of one-di-mensional time series(TS1d)with the extracted complexity features only at a single scale.Aiming at these problems,a new nonlinear dynamic analysis method termed two-dimensional composite multi-scale ensemble Gramian dispersion entropy(CMEGDE_(2D))is proposed in this paper.First,the TS_(1D) is transformed into a two-dimensional image(I_(2D))by using Gramian angular fields(GAF)with more internal data structures and geometri features,which preserve the global characteristics and time dependence of vibration signals.Second,the I2D is analyzed at multiple scales through the composite coarse-graining method,which overcomes the limitation of a single scale and provides greater stability compared to traditional coarse-graining methods.Subsequently,a new fault diagnosis method of rolling bearing is proposed based on the proposed CMEGDE_(2D) for fault feature ex-traction and the chicken swarm algorithm optimized support vector machine(CsO-SvM)for fault pattern identification.The simulation signals and two data sets of rolling bearings are utilized to verify the effectiveness of the proposed fault diagnosis method.The results demonstrate that the proposed method has stronger dis-crimination ability,higher fault diagnosis accuracy and better stability than the other compared methods.展开更多
A novel method that combines reinforced enzyme-induced carbonate precipitation(REICP)was proposed to improve the mechanical properties of dispersive soil.Dispersive soils,which are highly susceptible to erosion caused...A novel method that combines reinforced enzyme-induced carbonate precipitation(REICP)was proposed to improve the mechanical properties of dispersive soil.Dispersive soils,which are highly susceptible to erosion caused by rainfall or seepage,pose significantenvironmental challenges.It is essential to focus on modifying dispersive soil using environmentally friendly methods.This study investigated the cohesion,internal friction angle,permeability,hydrostability test,and microstructure of dispersive soil treated with enzyme-induced carbonate precipitation(EICP)-MgCl2-xanthan gum(REICP),using statistical analysis.A series of laboratory experiments was conducted,including direct shear tests,permeability experiments,mud ball tests,simulated rainfall tests,Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),and scanning electron microscopy(SEM).The results showed that the combined treatment significantly enhanced the mechanical properties of dispersive soil.At the optimal ratio,cohesion increased by a factor of 2,and the permeability coefficientdecreased by approximately 1.7×10^(7)times.Additionally,the strength parameters gradually increased with curing time.Microstructural analyses indicated that calcite precipitation,pore filling,and ionic redistribution significantlyimproved the mechanical properties and hydrostability of the soil.Statistical analyses showed that EICP materials and xanthan gum increased soil cohesion,while magnesium chloride enhanced the internal friction angle and reduced porosity.This study integrates mechanical testing,statistical analysis,and microstructural evaluation to propose a sustainable and environmentally friendly method for improving dispersive soils.This approach reduces the use of chemical modifiers,minimizes environmental impacts,and demonstrates application potential in the stabilization of dispersive soils.展开更多
The relative dispersion of cloud and fog droplets has significant impacts on aerosol indirect effects,radiative transfer,and microphysical processes.However,previous studies have been mostly concerned with clouds,with...The relative dispersion of cloud and fog droplets has significant impacts on aerosol indirect effects,radiative transfer,and microphysical processes.However,previous studies have been mostly concerned with clouds,with limited studies on fog,particularly those that examine the combined influences of all key physical processes and their roles during fog evolution.As such,this study aims to conduct a comprehensive investigation by examining the relationships between relative dispersion and other microphysical variables,as well as the underlying microphysical and dynamic processes,based on field fog campaigns in polluted and clean conditions.In polluted fog,droplet concentrations are higher,leading to smaller droplets and increased dispersion.The correlation between dispersion and droplet volume-mean radius is positive in the polluted fog,but shifts to negative in clean fog.We attribute the difference to various microphysical processes like aerosol activation,condensation,collision-coalescence,and entrainment-mixing.In polluted fog,high aerosol concentrations,low supersaturations,and strong turbulence(entrainment-mixing)provide suitable conditions for the simultaneous occurrence of droplet condensation and aerosol activation,resulting in a positive correlation between dispersion and volume-mean radius,especially during the fog formation stage.In contrast,during the mature stage in clean fog,condensation is dominant with weak aerosol activation leading to a negative correlation between relative dispersion and volume-mean radius.The collision-coalescence process is more active in the mature stage,increasing radii and leading to the negative correlation between dispersion and volume-mean radius.This result sheds new light on understanding the relative dispersion and mechanisms in fog under different aerosol backgrounds.展开更多
Single-atom catalysts(SACs)have demonstrated excellent performance in heterogeneous catalytic reactions owing to their maximized atomic efficiency,distinctive geometric,and electronic configurations.However,the effica...Single-atom catalysts(SACs)have demonstrated excellent performance in heterogeneous catalytic reactions owing to their maximized atomic efficiency,distinctive geometric,and electronic configurations.However,the efficacy of SACs remains limited for certain reactions requiring simultaneous activation of multiple reactants over metallic active sites.Herein,we report an atomically dispersed Pt1Ru1 dual-atom pair site anchored on nanodiamond@graphene(ND@G)for CO oxidation.The Pt1Ru1 dual-atom catalyst shows an exceptional turnover frequency(TOF)of 17.6.10^(-2)s^(-1)at significantly lower temperature(30℃),achieving a tenfold increase in TOF compared to singleatom Pt1/ND@G catalyst(1.5.10^(-2)s^(-1))and surpassing to previously reported Pt-based catalysts under similar conditions.Moreover,the catalyst demonstrates excellent stability,maintaining its activity for 40 h at 80℃without significant deactivation.The superior catalytic performance of Pt-Ru dual-atom catalysts is attributed to the synergistic effect between Pt and Ru atoms with enhanced metallicity for improving simultaneous adsorption and activation of CO and O_(2),and the tuning of conventional competitive reactant adsorption into a non-competitive pathway over dual-atom pair sites.The present work manifests the advantages of dual-atom pair sites in heterogeneous catalysis and paves the way for precise design of catalysts at the atomic scale.展开更多
Nanoparticle-reinforced Mg matrix composites(NPMMCs)capitalize on the synergistic properties of nanoparticles and Mg matrix,resulting in enhanced mechanical attributes compared to matrix.Nonetheless,effective high-tem...Nanoparticle-reinforced Mg matrix composites(NPMMCs)capitalize on the synergistic properties of nanoparticles and Mg matrix,resulting in enhanced mechanical attributes compared to matrix.Nonetheless,effective high-temperature dispersion of nanoparticles remains challenging.This study employs a molten salt dispersant(NaCl-KCl-MgCl_(2))effectively mitigating the oxidation and combustion of TiC nanoparticles(TiC_(np)).Compared with the atmosphere,the molten salt facilitates the pre-dispersion of TiC_(np)through thermal motion at elevated temperatures,thereby reducing agglomeration between the TiC_(np).Simultaneously,the molten salt effectively wets and disrupts the oxide layer on the surface of Mg melt,facilitating the wetting of TiC_(np)by the Mg melt.The successful incorporation of 3 vol.%TiC_(np)into the Mg matrix is achieved by utilizing molten salt,and the addition of TiC_(np)increases the viscosity of mg melt.Further dispersed by ultrasonic dispersion,the unique distribution of TiC_(np)within ring-like structures was obtained which was attributed to the increase of viscosity.As a configurational distribution,the ring-like TiC_(np)distribution morphology significantly enhances the mechanical properties of composites,as evidenced by an approximate 50%increase in compressive strength(UCS).展开更多
This letter addresses challenges in the clinical translation of BIBR1532,a promising telomerase inhibitor,for the treatment of esophageal squamous cell carcinoma(ESCC).BIBR1532 exerts its anti-cancer effect by activat...This letter addresses challenges in the clinical translation of BIBR1532,a promising telomerase inhibitor,for the treatment of esophageal squamous cell carcinoma(ESCC).BIBR1532 exerts its anti-cancer effect by activating DNA damage response(ATR/CHK1 and ATM/CHK2)pathways and downregulating telomere-binding proteins.Although its therapeutic potential is limited by poor aqueous solubility,solid dispersion(SD)technology may overcome this obstacle.Systematic analysis using PubChem-derived simplified molecular input line entry system identifiers and artificial intelligence-driven FormulationDT platform evaluation(oral formulation feasibility index:0.38)revealed that the SD technology,with superior scalability(32 approved products by 2021)and lower production risks,outperforms lipid-based formulations as an optimal dissolution strategy.Material analysis revealed hydroxypropyl methylcellulose(HPMC)as the optimal carrier with lower hygroscopicity,higher temperature and no intestinal targeting,thus enabling ESCC therapy.HPMC-based SD enhances BIBR1532 solubility and bioavailability for effective ESCC treatment.Future studies should focus on pilot tests for SD fabrication.展开更多
Prevention of biological invasion requires understanding how alien species invade native communities.Although studies have identified mechanisms that underlie plant invasion in some habitats,limited attention has focu...Prevention of biological invasion requires understanding how alien species invade native communities.Although studies have identified mechanisms that underlie plant invasion in some habitats,limited attention has focused on invasion patterns along elevational gradients.In this study,we asked which factors drive the global and regional distribution of the invasive plant Galinsoga quadriradiata along elevational gradients.To answer this question,we examined whether human activities(i.e.,roads)promote G.quadriradiata invasion,how seed dispersal-related traits of G.quadriradiata change along elevation gradients,and whether G.quadriradiata has adapted to high-elevation environments through phenotypic plasticity or genetic variation.On the global scale,we found that human activities and road density positively contribute to the G.quadriradiata expansion in mountainous areas.Field surveys in China revealed significant elevational differences in the seed dispersal traits of G.quadriradiata,with higher-elevation populations exhibiting lower dispersal ability and generally lower genetic diversity.Under common conditions,high-elevation populations showed higher leaf mass ratio but lower root mass ratio and reproductive allocation.This suggests that high-elevation environments create a barrier to dispersal for G.quadriradiata,and that G.quadriradiata has adapted phenotypically to these conditions.Our study indicates that the elevational invasion pattern of G.quadriradiata is shaped by multiple factors,particularly human activities and phenotypic adaptability.In addition,our finding that G.quadriradiata invasion at high elevations is not constrained by low genetic diversity indicates that monitoring and management of G.quadriradiata in mountainous areas should be strengthened.展开更多
In the dispersed computing environment driven by intelligent networks,intrusion detection faces significant challenges.This paper proposes a multilayer decentralized federated learning framework based on mean field ga...In the dispersed computing environment driven by intelligent networks,intrusion detection faces significant challenges.This paper proposes a multilayer decentralized federated learning framework based on mean field game theory(MFG-DFL).The framework organizes networked computing points(NCPs)into a three-layer collaborative architecture,and innovatively introduces MFG theory to model the complex dynamic interactions,which among large-scale NCPs as a game between a representative NCP and the mean field.By solving the coupled HJB and FPK equations,we design a dynamic incentive mechanism to fairly quantify and reward NCP contributions,thus aligning individual rationality with the global objectives of the system.The simulation results on the CICIoT2023 data set demonstrate the outstanding performance of the proposed framework.Specifically,it achieves an intrusion detection accuracy of 81.09%in highly non-IID scenarios,showcasing a well-balanced trade-off between computational efficiency and performance enhancement.展开更多
Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening pa...Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening particles also deteriorates the processability and it is of great importance to establish accurate processing maps to guide the thermomechanical processes to enhance the formability.In this study,we performed particle swarm optimization-based back propagation artificial neural network model to predict the high temperature flow behavior of 0.25wt%Al2O3 particle-reinforced Cu alloys,and compared the accuracy with that of derived by Arrhenius-type constitutive model and back propagation artificial neural network model.To train these models,we obtained the raw data by fabricating ODS Cu alloys using the internal oxidation and reduction method,and conducting systematic hot compression tests between 400 and800℃with strain rates of 10^(-2)-10 S^(-1).At last,processing maps for ODS Cu alloys were proposed by combining processing parameters,mechanical behavior,microstructure characterization,and the modeling results achieved a coefficient of determination higher than>99%.展开更多
To simultaneously enrich,separate,and determine five fluoroquinolone antibiotics(FQs)in marine crude drugs(MCDs),seawater and seafood,we conducted this study using vortex assisted dispersed liquid-liquid microextracti...To simultaneously enrich,separate,and determine five fluoroquinolone antibiotics(FQs)in marine crude drugs(MCDs),seawater and seafood,we conducted this study using vortex assisted dispersed liquid-liquid microextraction(DLLME),followed by capillary electrophoresis(CE)-UV.A single-variable optimization was employed to examine the factors influencing the separation effect of CE and the extraction efficiency of DLLME,including buffer solution,organic solvent,separation voltage,extractant,dispersant,and sample solution pH.Under the optimal conditions,the baseline separation of the five FQs was achieved within 6 min.The analytical performance of the method was assessed using six types of actual samples,including three MCDs of hippocampus,clam,and kelp,seawater,and two seafood of prawn and pomfret,demonstrating good linearity ranging from 0.1-5 or 0.01-5μg/mL.The limits of detection(LODs)and limits of quantification(LOQs)for the five FQs in MCDs were 0.0022-0.0292 and 0.0066-0.0973μg/mL,respectively.The LODs and LOQs in seawater and seafood were 0.0009-0.0262 and 0.0029-0.0874μg/mL,respectively.The matrix effects of this method were evaluated in the hippocampus,seawater,and prawn,and the results show that DLLME could effectively eliminate matrix interference.Satisfactory recovery rates were achieved in all the six tested actual samples.This developed DLLME-CE method was proven simple to operate,accurate and reliable,with high sensitivity,making it suitable for the analysis of multiple antibiotic residues in complex matrices.展开更多
To fully utilize the resources provided by optical fiber networks,a cross-band quantum light source generating photon pairs,where one photon in a pair is at C band and the other is at O band,is proposed in this work.T...To fully utilize the resources provided by optical fiber networks,a cross-band quantum light source generating photon pairs,where one photon in a pair is at C band and the other is at O band,is proposed in this work.This source is based on spontaneous four-wave mixing(SFWM)in a piece of shallow-ridge silicon waveguide.Theoretical analysis shows that the waveguide dispersion could be tailored by adjusting the ridge width,enabling broadband photon pair generation by SFWM across C band and O band.The spontaneous Raman scattering(SpRS)in silicon waveguides is also investigated experimentally.It shows that there are two regions in the spectrum of generated photons from SpRS,which could be used to achieve cross-band photon pair generation.A chip of shallow-ridge silicon waveguide samples with different ridge widths has been fabricated,through which cross-band photon pair generation is demonstrated experimentally.The experimental results show that the source can be achieved using dispersion-optimized shallow-ridge silicon waveguides.This cross-band quantum light source provides a way to develop new fiber-based quantum communication functions utilizing both C band and O band and extends applications of quantum networks.展开更多
Some patients with systemic lupus erythematosus experience neuropsychiatric symptoms.Although magnetic resonance imaging can detect abnormal signals in the white matter of the brain,conventional methods often struggle...Some patients with systemic lupus erythematosus experience neuropsychiatric symptoms.Although magnetic resonance imaging can detect abnormal signals in the white matter of the brain,conventional methods often struggle to accurately capture microstructural changes.Various diffusion models have been used to study white matter in systemic lupus erythematosus;however,comparative analyses of their sensitivity and specificity for detecting microstructural changes remain insufficient.To address this,our team designed a diagnostic trial that used multimodal diffusion imaging techniques to observe white matter microstructural changes in patients with systemic lupus erythematosus who had neuropsychiatric symptoms,with an aim to identify key diagnostic biomarkers for these patients.Patients with active lupus who received treatment at the Department of Rheumatology and Immunology,The First Affiliated Hospital of China Medical University,from September 2023 to March 2024 were recruited.According to the standards of the American College of Rheumatology,patients with systemic lupus erythematosus who had neuropsychiatric symptoms were assigned to the systemic lupus erythematosus group,whereas those without neuropsychiatric symptoms were assigned to the non-systemic lupus erythematosus group.Additionally,healthy volunteers matched by region,sex,and age were recruited as controls.All three groups underwent the same diffusion magnetic resonance imaging examination protocol to compare differences in diffusion parameters.Advanced diffusion imaging models were able to sensitively detect microstructural changes in the white matter fibers of patients with systemic lupus erythematosus who had neuropsychiatric symptoms,with specific diffusion parameters showing significant abnormalities in key brain regions.In the left superior longitudinal fasciculus subregion and the right thalamic radiations of patients with systemic lupus erythematosus who had neuropsychiatric symptoms,we also identified abnormal diffusion characteristics that were clearly correlated with disease activity,suggesting that microstructural changes in these areas may reflect the dynamic process of neuroinflammatory damage.The present study addresses critical challenges in the diagnosis of systemic lupus erythematosus by identifying specific white matter imaging biomarkers and elucidating the association between microstructural damage and clinical manifestations.The main contributions of our study include:1)establishing axial regression probability parameters from mean apparent propagator magnetic resonance imaging as sensitive biomarkers for systemic lupus erythematosus,particularly in the third subregion of the left superior longitudinal fasciculus;2)demonstrating that multimodal diffusion imaging may be superior to conventional diffusion tensor imaging for detecting white matter microstructural abnormalities in patients with systemic lupus erythematosus;and 3)integrating tract-based spatial statistics with clinically relevant analyses to link imaging findings to pathological mechanisms.展开更多
Aims The evolution and expression of dispersal-related traits are intertwined with those of other life-history functions and are manifested within various physiological constraints.Such a relationship is predicted bet...Aims The evolution and expression of dispersal-related traits are intertwined with those of other life-history functions and are manifested within various physiological constraints.Such a relationship is predicted between inbreeding levels and dispersability,which may be anatomically and ontogenetically linked so that the selection pressures on one may affect the other.While both the effect of inbreeding on reproductive success and on dispersal strategies received much attention,only a few studies considered both simultaneously.Furthermore,such studies often rely on two dichotomic representations of breeding and dispersal:using selfing versus outcrossing as a representation of breeding level,and dispersal ratio as the sole representation of dispersal strategy.Methods Here,we used pollination experiments in the heterocarpic Crepis sancta(Asteraceae)to expand in two different manners on the common practice of using dichotomic representations of breeding and dispersal.First,we used pollination treatments that represent a continuum from selfing through pollination by kin to pollination by a distant neighbor.Second,we measured a whole set of continuous morphological and dispersal-related traits,in addition to measurements of reproductive success and dispersal ratio.Important Findings The proportion of developed capitula and the number of both dispersed and non-dispersed achenes were significantly lower in the self-pollination treatment in comparison to the outcrossed treatments.The effect of pollen sources on dispersal ratio was not statistically significant,though self-pollinated plants rarely produced non-dispersing seeds.Achene's biomass increased with distance between parent plants,but pappus width did not,leading to a nonsignificant effect of pollination on falling velocity.Overall,pollen source affected mainly traits that were associated with reproductive output,but it had no clear effect on predominately dispersal-related traits.Such differences in the response of reproduction and dispersal traits to variation in pollen source suggest that dispersal-related selection is probably weak and/or masked by other forces.展开更多
The mechanical properties and oxidation resistance of two nickel-based superalloys with and without oxide dispersion strengthened(ODS)phases at different temperatures were studied.The microstructure was investigated b...The mechanical properties and oxidation resistance of two nickel-based superalloys with and without oxide dispersion strengthened(ODS)phases at different temperatures were studied.The microstructure was investigated by scanning electron microscopy(SEM),electron backscatter diffraction(EBSD),and transmission electron microscopy(TEM).The results show that the yield strength of the samples with and without ODS phases at room temperature is 1020 and 324 MPa,respectively.The yield strength model was constructed,and it is found that the contribution of grain boundary strengthening,dislocation strengthening and nanoparticle strengthening of nickel-based ODS superalloy exceeds 83%.As the temperature increases,grain boundary sliding and migration decrease the strength of sample but improve its ductility.Oxidation hinders the ductility of sample and intensifies its fracture,and the maximum elongation of nickel-based ODS superalloy at 800℃ is 47.3%.展开更多
River embankments are designed to defend against floods over coastal and riparian areas.It is important to early detect unexpected damages on embankments before they exacerbate.To continuously monitor the stability of...River embankments are designed to defend against floods over coastal and riparian areas.It is important to early detect unexpected damages on embankments before they exacerbate.To continuously monitor the stability of the embankments and efficiently recognize such potential damages,this study takes SAR(Synthetic Aperture Radar)derived deformation as an indicator of the embankment instability,and customizes a multi-temporal InSAR(Interferometric SAR)approach-small baseline subset.Specifically,during InSAR processing,we apply a two-step amplitude difference dispersion threshold method to extract InSAR measurement points,thus improving the point density within the embankment.We applied this method to the Kangshan Embankment(KE)using 147 Sentinel-1 acquired between 2017 and 2021.We categorized KE into Waterside Slope(WS),Embankment Top(ET),and Landside Slope(LS)using InSAR height estimation.Given the dominance of downslope movement,we developed a projection matrix from InSAR-derived deformation in the satellite line-of-sight direction onto WS and LS.The study shows that KE was generally stable during the five-year period,while WS,ET,and LS experienced different deformation processes.For instance,seasonal variation was observed from the deformation time series,especially between every April and November.We applied the principal component analysis to the time-series displacement and analyzed the results in conjunction with the rainfall data of Kangshan Township.It showed that deformation due to rainfall equals 80.93%,81.30%,and 82.46%of the total deformation for WS,ET,and LS,respectively,indicating that rainfall is one of the environmental driving factors affecting the deformations.We conclude that the proposed methodology is suited for systematic embankment monitoring and identifies major driving forces.展开更多
In this paper,we theoretically study the Lamb wave in a multilayered piezoelectric semiconductor(PSC)plate,where each layer is an n-type PSC with the symmetry of transverse isotropy.Based on the extended Stroh formali...In this paper,we theoretically study the Lamb wave in a multilayered piezoelectric semiconductor(PSC)plate,where each layer is an n-type PSC with the symmetry of transverse isotropy.Based on the extended Stroh formalism and dual-variable and position(DVP)method,the general solution of the coupled fields for the Lamb wave is derived,and then the dispersion equation is obtained by the application of the boundary conditions.First,the influence of semiconducting properties on the dispersion behavior of the Lamb wave in a single-layer PSC plate is analyzed.Then,the propagation characteristics of the Lamb wave in a sandwich plate are investigated in detail.The numerical results show that the wave speed and attenuation depend on the stacking sequence,layer thickness,and initial carrier density,the Lamb wave can propagate without a cut-off frequency in both the homogeneous and multilayer PSC plates due to the semiconducting properties,and the Lamb wave without attenuation can be achieved by carefully selecting the semiconductor property in the upper and lower layers.These new features could be very helpful as theoretical guidance for the design and performance optimization of PSC devices.展开更多
Metal-based catalysts are prevalent in the CO_(2) hydrogenation to methanol owing to their remarkable catalytic activity.Herein,Ru/In_(2)O_(3) catalysts with different morphologies obtained by doping Ru into In_(2)O_(...Metal-based catalysts are prevalent in the CO_(2) hydrogenation to methanol owing to their remarkable catalytic activity.Herein,Ru/In_(2)O_(3) catalysts with different morphologies obtained by doping Ru into In_(2)O_(3) with irregular,rod-like,and flower-like morphologies are used for catalytic CO_(2) hydrogenation to methanol.Results indicate that the flower-like Ru/In_(2)O_(3)(Ru/In_(2)O_(3)-F)exhibits higher catalytic performance than Ru/In_(2)O_(3) with other morphologies,achieving a 12.9%CO_(2) conversion,74.02%methanol selectivity,and 671.36 mg_(MeOH) h^(−1) g_(cat)^(−1) methanol spatiotemporal yield.Furthermore,Ru/In_(2)O_(3)-F maintains its catalytic stability over 200 h at 5 MPa and 290℃.The promotional effect mainly stems from the fact that electronic structure of Ru can be effectively adjusted by modulating the morphology of In_(2)O_(3).The strong interaction between atomically dispersed Ru and In_(2)O_(3)-F enhances the structural stability of Ru,inhibiting the agglomeration of the catalyst during the reaction process.Furthermore,density-functional theory calculations reveal that highly dispersed Ru atoms not only perform efficient and rapid electronic gain and loss processes,facilitating the catalytic activation of H_(2) into H intermediates.It also enables the generated reactive H to rapidly overflow to the surrounding In sites to participate in CO_(2) reduction.These findings provide a theoretical basis for the development of high-performance catalysts for CO_(2) hydrogenation.展开更多
Fine particulatematter(PM_(2.5))samples were collected in two neighboring cities,Beijing and Baoding,China.High-concentration events of PM_(2.5) in which the average mass concentration exceeded 75μg/m^(3) were freque...Fine particulatematter(PM_(2.5))samples were collected in two neighboring cities,Beijing and Baoding,China.High-concentration events of PM_(2.5) in which the average mass concentration exceeded 75μg/m^(3) were frequently observed during the heating season.Dispersion Normalized Positive Matrix Factorization was applied for the source apportionment of PM_(2.5) as minimize the dilution effects of meteorology and better reflect the source strengths in these two cities.Secondary nitrate had the highest contribution for Beijing(37.3%),and residential heating/biomass burning was the largest for Baoding(27.1%).Secondary nitrate,mobile,biomass burning,district heating,oil combustion,aged sea salt sources showed significant differences between the heating and non-heating seasons in Beijing for same period(2019.01.10–2019.08.22)(Mann-Whitney Rank Sum Test P<0.05).In case of Baoding,soil,residential heating/biomass burning,incinerator,coal combustion,oil combustion sources showed significant differences.The results of Pearson correlation analysis for the common sources between the two cities showed that long-range transported sources and some sources with seasonal patterns such as oil combustion and soil had high correlation coefficients.Conditional Bivariate Probability Function(CBPF)was used to identify the inflow directions for the sources,and joint-PSCF(Potential Source Contribution Function)was performed to determine the common potential source areas for sources affecting both cities.These models facilitated a more precise verification of city-specific influences on PM_(2.5) sources.The results of this study will aid in prioritizing air pollution mitigation strategies during the heating season and strengthening air quality management to reduce the impact of downwind neighboring cities.展开更多
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2022M3H4A6A0103720142)the National Research Council of Science&Technology(NST)grant by the Korea government(MSIT)(No.GTL24011-000)+1 种基金the Technology Innovation Program(RS-2024-00404165)through the Korea Planning&Evaluation Institute of Industrial Technology(KEIT)funded by the Ministry of Trade,Industry&Energy(MOTIE,Korea)supported by the Samsung SDI Co.Ltd.and the Korea Institute of Science and Technology(KIST)institutional program(2E33942,2E3394B)。
文摘Strategies for achieving high-energy-density lithium-ion batteries include using high-capacity materials such as high-nickel NCM,increasing the active material content in the electrode by utilizing high-conductivity carbon nanotubes(CNT)conductive materials,and electrode thickening.However,these methods are still limited due to the limitation in the capacity of high-nickel NCM,aggregation of CNT conductive materials,and nonuniform material distribution of thick-film electrodes,which ultimately damage the mechanical and electrical integrity of the electrode,leading to a decrease in electrochemical performance.Here,we present an integrated binder-CNT composite dispersion solution to realize a high-solids-content(>77 wt%)slurry for high-mass-loading electrodes and to mitigate the migration of binder and conductive additives.Indeed,the approach reduces solvent usage by approximately 30%and ensures uniform conductive additive-binder domain distribution during electrode manufacturing,resulting in improved coating quality and adhesive strength for high-mass-loading electrodes(>12 mAh cm^(−2)).In terms of various electrode properties,the presented electrode showed low resistance and excellent electrochemical properties despite the low CNT contents of 0.6 wt%compared to the pristine-applied electrode with 0.85 wt%CNT contents.Moreover,our strategy enables faster drying,which increases the coating speed,thereby offering potential energy savings and supporting carbon neutrality in wet-based electrode manufacturing processes.
基金Supported by the National Natural Science Foundation of China(Grant No.51975004)the Outstanding Youth Fund of Universities in Anhui Province of China(Grant No.2022AH020032).
文摘One-dimensional ensemble dispersion entropy(EDE1D)is an effective nonlinear dynamic analysis method for complexity measurement of time series.However,it is only restricted to assessing the complexity of one-di-mensional time series(TS1d)with the extracted complexity features only at a single scale.Aiming at these problems,a new nonlinear dynamic analysis method termed two-dimensional composite multi-scale ensemble Gramian dispersion entropy(CMEGDE_(2D))is proposed in this paper.First,the TS_(1D) is transformed into a two-dimensional image(I_(2D))by using Gramian angular fields(GAF)with more internal data structures and geometri features,which preserve the global characteristics and time dependence of vibration signals.Second,the I2D is analyzed at multiple scales through the composite coarse-graining method,which overcomes the limitation of a single scale and provides greater stability compared to traditional coarse-graining methods.Subsequently,a new fault diagnosis method of rolling bearing is proposed based on the proposed CMEGDE_(2D) for fault feature ex-traction and the chicken swarm algorithm optimized support vector machine(CsO-SvM)for fault pattern identification.The simulation signals and two data sets of rolling bearings are utilized to verify the effectiveness of the proposed fault diagnosis method.The results demonstrate that the proposed method has stronger dis-crimination ability,higher fault diagnosis accuracy and better stability than the other compared methods.
基金supported by the National Natural Science Foundation of China(Grant No.42407199)Heilongjiang Provincial Natural Science Foundation of China(Grant No.PL2024D003)the Fundamental Research Funds for the Central Universities(Grant No.2572023CT17).
文摘A novel method that combines reinforced enzyme-induced carbonate precipitation(REICP)was proposed to improve the mechanical properties of dispersive soil.Dispersive soils,which are highly susceptible to erosion caused by rainfall or seepage,pose significantenvironmental challenges.It is essential to focus on modifying dispersive soil using environmentally friendly methods.This study investigated the cohesion,internal friction angle,permeability,hydrostability test,and microstructure of dispersive soil treated with enzyme-induced carbonate precipitation(EICP)-MgCl2-xanthan gum(REICP),using statistical analysis.A series of laboratory experiments was conducted,including direct shear tests,permeability experiments,mud ball tests,simulated rainfall tests,Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),and scanning electron microscopy(SEM).The results showed that the combined treatment significantly enhanced the mechanical properties of dispersive soil.At the optimal ratio,cohesion increased by a factor of 2,and the permeability coefficientdecreased by approximately 1.7×10^(7)times.Additionally,the strength parameters gradually increased with curing time.Microstructural analyses indicated that calcite precipitation,pore filling,and ionic redistribution significantlyimproved the mechanical properties and hydrostability of the soil.Statistical analyses showed that EICP materials and xanthan gum increased soil cohesion,while magnesium chloride enhanced the internal friction angle and reduced porosity.This study integrates mechanical testing,statistical analysis,and microstructural evaluation to propose a sustainable and environmentally friendly method for improving dispersive soils.This approach reduces the use of chemical modifiers,minimizes environmental impacts,and demonstrates application potential in the stabilization of dispersive soils.
基金supported by the Chinese National Natural Science Foundation under Grant Nos.(41975181,42325503,42375197,42575207,42205090)Y.LIU is supported by the U.S.Department of Energy’s Atmospheric System Research(ASR)program.
文摘The relative dispersion of cloud and fog droplets has significant impacts on aerosol indirect effects,radiative transfer,and microphysical processes.However,previous studies have been mostly concerned with clouds,with limited studies on fog,particularly those that examine the combined influences of all key physical processes and their roles during fog evolution.As such,this study aims to conduct a comprehensive investigation by examining the relationships between relative dispersion and other microphysical variables,as well as the underlying microphysical and dynamic processes,based on field fog campaigns in polluted and clean conditions.In polluted fog,droplet concentrations are higher,leading to smaller droplets and increased dispersion.The correlation between dispersion and droplet volume-mean radius is positive in the polluted fog,but shifts to negative in clean fog.We attribute the difference to various microphysical processes like aerosol activation,condensation,collision-coalescence,and entrainment-mixing.In polluted fog,high aerosol concentrations,low supersaturations,and strong turbulence(entrainment-mixing)provide suitable conditions for the simultaneous occurrence of droplet condensation and aerosol activation,resulting in a positive correlation between dispersion and volume-mean radius,especially during the fog formation stage.In contrast,during the mature stage in clean fog,condensation is dominant with weak aerosol activation leading to a negative correlation between relative dispersion and volume-mean radius.The collision-coalescence process is more active in the mature stage,increasing radii and leading to the negative correlation between dispersion and volume-mean radius.This result sheds new light on understanding the relative dispersion and mechanisms in fog under different aerosol backgrounds.
基金supported by the National Key R&D Program of China (2021YFA1502802)the National Natural Science Foundation of China (U21B2092, 22202213, 22402210, 22502215, 22502214, 22572200, and 22579171)+3 种基金the International Partnership Program of Chinese Academy of Sciences (172GJHZ2022028MI)the Shenyang Bureau of Science and Technology (24-213-3-25)the Natural Science Foundation of Liaoning Province (2025BS0153)Zhongke Technology Achievement Transfer and Transformation Center of Henan Province 2025119
文摘Single-atom catalysts(SACs)have demonstrated excellent performance in heterogeneous catalytic reactions owing to their maximized atomic efficiency,distinctive geometric,and electronic configurations.However,the efficacy of SACs remains limited for certain reactions requiring simultaneous activation of multiple reactants over metallic active sites.Herein,we report an atomically dispersed Pt1Ru1 dual-atom pair site anchored on nanodiamond@graphene(ND@G)for CO oxidation.The Pt1Ru1 dual-atom catalyst shows an exceptional turnover frequency(TOF)of 17.6.10^(-2)s^(-1)at significantly lower temperature(30℃),achieving a tenfold increase in TOF compared to singleatom Pt1/ND@G catalyst(1.5.10^(-2)s^(-1))and surpassing to previously reported Pt-based catalysts under similar conditions.Moreover,the catalyst demonstrates excellent stability,maintaining its activity for 40 h at 80℃without significant deactivation.The superior catalytic performance of Pt-Ru dual-atom catalysts is attributed to the synergistic effect between Pt and Ru atoms with enhanced metallicity for improving simultaneous adsorption and activation of CO and O_(2),and the tuning of conventional competitive reactant adsorption into a non-competitive pathway over dual-atom pair sites.The present work manifests the advantages of dual-atom pair sites in heterogeneous catalysis and paves the way for precise design of catalysts at the atomic scale.
基金funded by the National Key Research&Development Program of China(grant no 2022YFB3705705)the National Natural Science Foundation of China(grant nos.52301142,52371107,52201115)+3 种基金the Heilongjiang Provincial Postdoctoral Science Foundation(grant no LBH-11Z22167)The Fundamental Research Funds for the Central Universities(grant no HIT.OCEF.2024035)The Science and Technology Innovation Program of Hunan Province(grant no 2022RC4012)The Shanxi Provincial Science and Technology Major Special Project plan of“Taking the lead in unveiling the list”[grant nos.202201050201012].
文摘Nanoparticle-reinforced Mg matrix composites(NPMMCs)capitalize on the synergistic properties of nanoparticles and Mg matrix,resulting in enhanced mechanical attributes compared to matrix.Nonetheless,effective high-temperature dispersion of nanoparticles remains challenging.This study employs a molten salt dispersant(NaCl-KCl-MgCl_(2))effectively mitigating the oxidation and combustion of TiC nanoparticles(TiC_(np)).Compared with the atmosphere,the molten salt facilitates the pre-dispersion of TiC_(np)through thermal motion at elevated temperatures,thereby reducing agglomeration between the TiC_(np).Simultaneously,the molten salt effectively wets and disrupts the oxide layer on the surface of Mg melt,facilitating the wetting of TiC_(np)by the Mg melt.The successful incorporation of 3 vol.%TiC_(np)into the Mg matrix is achieved by utilizing molten salt,and the addition of TiC_(np)increases the viscosity of mg melt.Further dispersed by ultrasonic dispersion,the unique distribution of TiC_(np)within ring-like structures was obtained which was attributed to the increase of viscosity.As a configurational distribution,the ring-like TiC_(np)distribution morphology significantly enhances the mechanical properties of composites,as evidenced by an approximate 50%increase in compressive strength(UCS).
基金Supported by“Continuation”Project of Excellent Doctors,Guangdong Basic and Applied Basic Research Foundation,No.2025A04J5082Guangdong Basic and Applied Basic Research Foundation,No.2024A1515011236.
文摘This letter addresses challenges in the clinical translation of BIBR1532,a promising telomerase inhibitor,for the treatment of esophageal squamous cell carcinoma(ESCC).BIBR1532 exerts its anti-cancer effect by activating DNA damage response(ATR/CHK1 and ATM/CHK2)pathways and downregulating telomere-binding proteins.Although its therapeutic potential is limited by poor aqueous solubility,solid dispersion(SD)technology may overcome this obstacle.Systematic analysis using PubChem-derived simplified molecular input line entry system identifiers and artificial intelligence-driven FormulationDT platform evaluation(oral formulation feasibility index:0.38)revealed that the SD technology,with superior scalability(32 approved products by 2021)and lower production risks,outperforms lipid-based formulations as an optimal dissolution strategy.Material analysis revealed hydroxypropyl methylcellulose(HPMC)as the optimal carrier with lower hygroscopicity,higher temperature and no intestinal targeting,thus enabling ESCC therapy.HPMC-based SD enhances BIBR1532 solubility and bioavailability for effective ESCC treatment.Future studies should focus on pilot tests for SD fabrication.
基金supported by the National Natural Science Foundation of China(32271584 and 31600445)the Natural Science Basic Research Plan in Shaanxi Province of China(2020JM-286)+2 种基金the Fundamental Research Funds for the Central Universities(GK202103072,GK202103073)the National College Students'Innovative Entrepreneurial Training Plan Program(202310718085)Special Research Project in Philosophy and Social Sciences of Shaanxi Province(2022HZ1795).
文摘Prevention of biological invasion requires understanding how alien species invade native communities.Although studies have identified mechanisms that underlie plant invasion in some habitats,limited attention has focused on invasion patterns along elevational gradients.In this study,we asked which factors drive the global and regional distribution of the invasive plant Galinsoga quadriradiata along elevational gradients.To answer this question,we examined whether human activities(i.e.,roads)promote G.quadriradiata invasion,how seed dispersal-related traits of G.quadriradiata change along elevation gradients,and whether G.quadriradiata has adapted to high-elevation environments through phenotypic plasticity or genetic variation.On the global scale,we found that human activities and road density positively contribute to the G.quadriradiata expansion in mountainous areas.Field surveys in China revealed significant elevational differences in the seed dispersal traits of G.quadriradiata,with higher-elevation populations exhibiting lower dispersal ability and generally lower genetic diversity.Under common conditions,high-elevation populations showed higher leaf mass ratio but lower root mass ratio and reproductive allocation.This suggests that high-elevation environments create a barrier to dispersal for G.quadriradiata,and that G.quadriradiata has adapted phenotypically to these conditions.Our study indicates that the elevational invasion pattern of G.quadriradiata is shaped by multiple factors,particularly human activities and phenotypic adaptability.In addition,our finding that G.quadriradiata invasion at high elevations is not constrained by low genetic diversity indicates that monitoring and management of G.quadriradiata in mountainous areas should be strengthened.
基金National Science Foundation Project of China(62436004,62372317)National Key Research and Development Program of China(2023YFC3331702)。
文摘In the dispersed computing environment driven by intelligent networks,intrusion detection faces significant challenges.This paper proposes a multilayer decentralized federated learning framework based on mean field game theory(MFG-DFL).The framework organizes networked computing points(NCPs)into a three-layer collaborative architecture,and innovatively introduces MFG theory to model the complex dynamic interactions,which among large-scale NCPs as a game between a representative NCP and the mean field.By solving the coupled HJB and FPK equations,we design a dynamic incentive mechanism to fairly quantify and reward NCP contributions,thus aligning individual rationality with the global objectives of the system.The simulation results on the CICIoT2023 data set demonstrate the outstanding performance of the proposed framework.Specifically,it achieves an intrusion detection accuracy of 81.09%in highly non-IID scenarios,showcasing a well-balanced trade-off between computational efficiency and performance enhancement.
基金financial support of the National Natural Science Foundation of China(No.52371103)the Fundamental Research Funds for the Central Universities,China(No.2242023K40028)+1 种基金the Open Research Fund of Jiangsu Key Laboratory for Advanced Metallic Materials,China(No.AMM2023B01).financial support of the Research Fund of Shihezi Key Laboratory of AluminumBased Advanced Materials,China(No.2023PT02)financial support of Guangdong Province Science and Technology Major Project,China(No.2021B0301030005)。
文摘Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening particles also deteriorates the processability and it is of great importance to establish accurate processing maps to guide the thermomechanical processes to enhance the formability.In this study,we performed particle swarm optimization-based back propagation artificial neural network model to predict the high temperature flow behavior of 0.25wt%Al2O3 particle-reinforced Cu alloys,and compared the accuracy with that of derived by Arrhenius-type constitutive model and back propagation artificial neural network model.To train these models,we obtained the raw data by fabricating ODS Cu alloys using the internal oxidation and reduction method,and conducting systematic hot compression tests between 400 and800℃with strain rates of 10^(-2)-10 S^(-1).At last,processing maps for ODS Cu alloys were proposed by combining processing parameters,mechanical behavior,microstructure characterization,and the modeling results achieved a coefficient of determination higher than>99%.
基金Supported by the National Natural Science Foundation of China(No.22176210)the Major Innovation Fund of Shandong Province(No.2021ZDSYS23)。
文摘To simultaneously enrich,separate,and determine five fluoroquinolone antibiotics(FQs)in marine crude drugs(MCDs),seawater and seafood,we conducted this study using vortex assisted dispersed liquid-liquid microextraction(DLLME),followed by capillary electrophoresis(CE)-UV.A single-variable optimization was employed to examine the factors influencing the separation effect of CE and the extraction efficiency of DLLME,including buffer solution,organic solvent,separation voltage,extractant,dispersant,and sample solution pH.Under the optimal conditions,the baseline separation of the five FQs was achieved within 6 min.The analytical performance of the method was assessed using six types of actual samples,including three MCDs of hippocampus,clam,and kelp,seawater,and two seafood of prawn and pomfret,demonstrating good linearity ranging from 0.1-5 or 0.01-5μg/mL.The limits of detection(LODs)and limits of quantification(LOQs)for the five FQs in MCDs were 0.0022-0.0292 and 0.0066-0.0973μg/mL,respectively.The LODs and LOQs in seawater and seafood were 0.0009-0.0262 and 0.0029-0.0874μg/mL,respectively.The matrix effects of this method were evaluated in the hippocampus,seawater,and prawn,and the results show that DLLME could effectively eliminate matrix interference.Satisfactory recovery rates were achieved in all the six tested actual samples.This developed DLLME-CE method was proven simple to operate,accurate and reliable,with high sensitivity,making it suitable for the analysis of multiple antibiotic residues in complex matrices.
基金supported by the Quantum Science and Technology-National Science and Technology Major Project (Grant No.2024ZD0302502 for WZ)the National Natural Science Foundation of China(Grant No.92365210 for WZ)+1 种基金Tsinghua Initiative Scientific Research Program (for WZ)the project of Tsinghua University-Zhuhai Huafa Industrial Share Company Joint Institute for Architecture Optoelectronic Technologies (JIAOT,for YH)。
文摘To fully utilize the resources provided by optical fiber networks,a cross-band quantum light source generating photon pairs,where one photon in a pair is at C band and the other is at O band,is proposed in this work.This source is based on spontaneous four-wave mixing(SFWM)in a piece of shallow-ridge silicon waveguide.Theoretical analysis shows that the waveguide dispersion could be tailored by adjusting the ridge width,enabling broadband photon pair generation by SFWM across C band and O band.The spontaneous Raman scattering(SpRS)in silicon waveguides is also investigated experimentally.It shows that there are two regions in the spectrum of generated photons from SpRS,which could be used to achieve cross-band photon pair generation.A chip of shallow-ridge silicon waveguide samples with different ridge widths has been fabricated,through which cross-band photon pair generation is demonstrated experimentally.The experimental results show that the source can be achieved using dispersion-optimized shallow-ridge silicon waveguides.This cross-band quantum light source provides a way to develop new fiber-based quantum communication functions utilizing both C band and O band and extends applications of quantum networks.
基金supported by the National Natural Science Foundation Joint Fund,No.U22A20309(to PY)the Natural Science Foundation of LiaoningProvince,No.2023-MS-07(to HuL)the Unveiling Key Scientific and Technological Projects of Liaoning Province,No.2021JH1/10400051(to HuL).
文摘Some patients with systemic lupus erythematosus experience neuropsychiatric symptoms.Although magnetic resonance imaging can detect abnormal signals in the white matter of the brain,conventional methods often struggle to accurately capture microstructural changes.Various diffusion models have been used to study white matter in systemic lupus erythematosus;however,comparative analyses of their sensitivity and specificity for detecting microstructural changes remain insufficient.To address this,our team designed a diagnostic trial that used multimodal diffusion imaging techniques to observe white matter microstructural changes in patients with systemic lupus erythematosus who had neuropsychiatric symptoms,with an aim to identify key diagnostic biomarkers for these patients.Patients with active lupus who received treatment at the Department of Rheumatology and Immunology,The First Affiliated Hospital of China Medical University,from September 2023 to March 2024 were recruited.According to the standards of the American College of Rheumatology,patients with systemic lupus erythematosus who had neuropsychiatric symptoms were assigned to the systemic lupus erythematosus group,whereas those without neuropsychiatric symptoms were assigned to the non-systemic lupus erythematosus group.Additionally,healthy volunteers matched by region,sex,and age were recruited as controls.All three groups underwent the same diffusion magnetic resonance imaging examination protocol to compare differences in diffusion parameters.Advanced diffusion imaging models were able to sensitively detect microstructural changes in the white matter fibers of patients with systemic lupus erythematosus who had neuropsychiatric symptoms,with specific diffusion parameters showing significant abnormalities in key brain regions.In the left superior longitudinal fasciculus subregion and the right thalamic radiations of patients with systemic lupus erythematosus who had neuropsychiatric symptoms,we also identified abnormal diffusion characteristics that were clearly correlated with disease activity,suggesting that microstructural changes in these areas may reflect the dynamic process of neuroinflammatory damage.The present study addresses critical challenges in the diagnosis of systemic lupus erythematosus by identifying specific white matter imaging biomarkers and elucidating the association between microstructural damage and clinical manifestations.The main contributions of our study include:1)establishing axial regression probability parameters from mean apparent propagator magnetic resonance imaging as sensitive biomarkers for systemic lupus erythematosus,particularly in the third subregion of the left superior longitudinal fasciculus;2)demonstrating that multimodal diffusion imaging may be superior to conventional diffusion tensor imaging for detecting white matter microstructural abnormalities in patients with systemic lupus erythematosus;and 3)integrating tract-based spatial statistics with clinically relevant analyses to link imaging findings to pathological mechanisms.
基金This work was supported by the Sol Leshin Foundation and by the Israeli Science Foundation(834/15).
文摘Aims The evolution and expression of dispersal-related traits are intertwined with those of other life-history functions and are manifested within various physiological constraints.Such a relationship is predicted between inbreeding levels and dispersability,which may be anatomically and ontogenetically linked so that the selection pressures on one may affect the other.While both the effect of inbreeding on reproductive success and on dispersal strategies received much attention,only a few studies considered both simultaneously.Furthermore,such studies often rely on two dichotomic representations of breeding and dispersal:using selfing versus outcrossing as a representation of breeding level,and dispersal ratio as the sole representation of dispersal strategy.Methods Here,we used pollination experiments in the heterocarpic Crepis sancta(Asteraceae)to expand in two different manners on the common practice of using dichotomic representations of breeding and dispersal.First,we used pollination treatments that represent a continuum from selfing through pollination by kin to pollination by a distant neighbor.Second,we measured a whole set of continuous morphological and dispersal-related traits,in addition to measurements of reproductive success and dispersal ratio.Important Findings The proportion of developed capitula and the number of both dispersed and non-dispersed achenes were significantly lower in the self-pollination treatment in comparison to the outcrossed treatments.The effect of pollen sources on dispersal ratio was not statistically significant,though self-pollinated plants rarely produced non-dispersing seeds.Achene's biomass increased with distance between parent plants,but pappus width did not,leading to a nonsignificant effect of pollination on falling velocity.Overall,pollen source affected mainly traits that were associated with reproductive output,but it had no clear effect on predominately dispersal-related traits.Such differences in the response of reproduction and dispersal traits to variation in pollen source suggest that dispersal-related selection is probably weak and/or masked by other forces.
基金supported by the National Natural Science Foundation of China(No.52271177)Leading Talents Project of Scientific and Technological Innovation in Hunan Province,China(No.2021RC4036)+1 种基金the Natural Science Foundation of Hunan Province,China(Nos.2023JJ50172,2020JJ6069)State Key Laboratory of Materials Processing and Die&Mould Technology,Huazhong University of Science and Technology,China。
文摘The mechanical properties and oxidation resistance of two nickel-based superalloys with and without oxide dispersion strengthened(ODS)phases at different temperatures were studied.The microstructure was investigated by scanning electron microscopy(SEM),electron backscatter diffraction(EBSD),and transmission electron microscopy(TEM).The results show that the yield strength of the samples with and without ODS phases at room temperature is 1020 and 324 MPa,respectively.The yield strength model was constructed,and it is found that the contribution of grain boundary strengthening,dislocation strengthening and nanoparticle strengthening of nickel-based ODS superalloy exceeds 83%.As the temperature increases,grain boundary sliding and migration decrease the strength of sample but improve its ductility.Oxidation hinders the ductility of sample and intensifies its fracture,and the maximum elongation of nickel-based ODS superalloy at 800℃ is 47.3%.
基金National Natural Science Foundation of China(No.41830110)National Key Research Development Program of China(No.2018YFC1503603)+2 种基金State Scholarship Fund from the Chinese Scholarship Council(No.202206710096)Project of China Railway Corporation(No.2021-key-14,2021-major-08)The Joint Planning of Technology and Water Conservancy of Jiangxi Province(No.2022KSG01009).
文摘River embankments are designed to defend against floods over coastal and riparian areas.It is important to early detect unexpected damages on embankments before they exacerbate.To continuously monitor the stability of the embankments and efficiently recognize such potential damages,this study takes SAR(Synthetic Aperture Radar)derived deformation as an indicator of the embankment instability,and customizes a multi-temporal InSAR(Interferometric SAR)approach-small baseline subset.Specifically,during InSAR processing,we apply a two-step amplitude difference dispersion threshold method to extract InSAR measurement points,thus improving the point density within the embankment.We applied this method to the Kangshan Embankment(KE)using 147 Sentinel-1 acquired between 2017 and 2021.We categorized KE into Waterside Slope(WS),Embankment Top(ET),and Landside Slope(LS)using InSAR height estimation.Given the dominance of downslope movement,we developed a projection matrix from InSAR-derived deformation in the satellite line-of-sight direction onto WS and LS.The study shows that KE was generally stable during the five-year period,while WS,ET,and LS experienced different deformation processes.For instance,seasonal variation was observed from the deformation time series,especially between every April and November.We applied the principal component analysis to the time-series displacement and analyzed the results in conjunction with the rainfall data of Kangshan Township.It showed that deformation due to rainfall equals 80.93%,81.30%,and 82.46%of the total deformation for WS,ET,and LS,respectively,indicating that rainfall is one of the environmental driving factors affecting the deformations.We conclude that the proposed methodology is suited for systematic embankment monitoring and identifies major driving forces.
基金Project supported by the National Natural Science Foundation of China(Nos.U21A20430 and 12302202)the Hebei Natural Science Foundation of China(No.A2023210040)+1 种基金the Science and Technology Project of Hebei Education Department of China(No.BJ2025005)the Hebei Provincial Department of Human Resources and Social Security of China(No.C20220324)。
文摘In this paper,we theoretically study the Lamb wave in a multilayered piezoelectric semiconductor(PSC)plate,where each layer is an n-type PSC with the symmetry of transverse isotropy.Based on the extended Stroh formalism and dual-variable and position(DVP)method,the general solution of the coupled fields for the Lamb wave is derived,and then the dispersion equation is obtained by the application of the boundary conditions.First,the influence of semiconducting properties on the dispersion behavior of the Lamb wave in a single-layer PSC plate is analyzed.Then,the propagation characteristics of the Lamb wave in a sandwich plate are investigated in detail.The numerical results show that the wave speed and attenuation depend on the stacking sequence,layer thickness,and initial carrier density,the Lamb wave can propagate without a cut-off frequency in both the homogeneous and multilayer PSC plates due to the semiconducting properties,and the Lamb wave without attenuation can be achieved by carefully selecting the semiconductor property in the upper and lower layers.These new features could be very helpful as theoretical guidance for the design and performance optimization of PSC devices.
基金financially supported by the Key Laboratory of Carbon-based Energy Molecular Chemical Utilization Technology in Guizhou Province(No.2023008)Guizhou Provincial Science and Technology Projects(No.ZKZD2023004)+1 种基金One Hundred Person Project of Guizhou Province(No.GCC 2023013)Scientific and Technological Innovation Talents Team Project of Guizhou Province(No.CXTD2023029).
文摘Metal-based catalysts are prevalent in the CO_(2) hydrogenation to methanol owing to their remarkable catalytic activity.Herein,Ru/In_(2)O_(3) catalysts with different morphologies obtained by doping Ru into In_(2)O_(3) with irregular,rod-like,and flower-like morphologies are used for catalytic CO_(2) hydrogenation to methanol.Results indicate that the flower-like Ru/In_(2)O_(3)(Ru/In_(2)O_(3)-F)exhibits higher catalytic performance than Ru/In_(2)O_(3) with other morphologies,achieving a 12.9%CO_(2) conversion,74.02%methanol selectivity,and 671.36 mg_(MeOH) h^(−1) g_(cat)^(−1) methanol spatiotemporal yield.Furthermore,Ru/In_(2)O_(3)-F maintains its catalytic stability over 200 h at 5 MPa and 290℃.The promotional effect mainly stems from the fact that electronic structure of Ru can be effectively adjusted by modulating the morphology of In_(2)O_(3).The strong interaction between atomically dispersed Ru and In_(2)O_(3)-F enhances the structural stability of Ru,inhibiting the agglomeration of the catalyst during the reaction process.Furthermore,density-functional theory calculations reveal that highly dispersed Ru atoms not only perform efficient and rapid electronic gain and loss processes,facilitating the catalytic activation of H_(2) into H intermediates.It also enables the generated reactive H to rapidly overflow to the surrounding In sites to participate in CO_(2) reduction.These findings provide a theoretical basis for the development of high-performance catalysts for CO_(2) hydrogenation.
基金supported by the National Institute of Environmental Research(NIER)funded by the Ministry of Environment(No.NIER-2019-04-02-039)supported by Particulate Matter Management Specialized Graduate Program through the Korea Environmental Industry&Technology Institute(KEITI)funded by the Ministry of Environment(MOE).
文摘Fine particulatematter(PM_(2.5))samples were collected in two neighboring cities,Beijing and Baoding,China.High-concentration events of PM_(2.5) in which the average mass concentration exceeded 75μg/m^(3) were frequently observed during the heating season.Dispersion Normalized Positive Matrix Factorization was applied for the source apportionment of PM_(2.5) as minimize the dilution effects of meteorology and better reflect the source strengths in these two cities.Secondary nitrate had the highest contribution for Beijing(37.3%),and residential heating/biomass burning was the largest for Baoding(27.1%).Secondary nitrate,mobile,biomass burning,district heating,oil combustion,aged sea salt sources showed significant differences between the heating and non-heating seasons in Beijing for same period(2019.01.10–2019.08.22)(Mann-Whitney Rank Sum Test P<0.05).In case of Baoding,soil,residential heating/biomass burning,incinerator,coal combustion,oil combustion sources showed significant differences.The results of Pearson correlation analysis for the common sources between the two cities showed that long-range transported sources and some sources with seasonal patterns such as oil combustion and soil had high correlation coefficients.Conditional Bivariate Probability Function(CBPF)was used to identify the inflow directions for the sources,and joint-PSCF(Potential Source Contribution Function)was performed to determine the common potential source areas for sources affecting both cities.These models facilitated a more precise verification of city-specific influences on PM_(2.5) sources.The results of this study will aid in prioritizing air pollution mitigation strategies during the heating season and strengthening air quality management to reduce the impact of downwind neighboring cities.