Dispersion experiments were conducted to study the influence of metallic cations on the dispersibility of diaspore. The reaction mechanisms were investigated based on the analysis of zeta (ξ) potential and calculat...Dispersion experiments were conducted to study the influence of metallic cations on the dispersibility of diaspore. The reaction mechanisms were investigated based on the analysis of zeta (ξ) potential and calculations of solution chemistry and DLVO theory. The results show that the valence of cations, instead of the cation type, plays an important role in the dispersibility of diaspore The impact of multivalent metallic cations is greater than that of monovalent cations. In the presence of Ca^2+ and Mg^2+, the dispersion of diaspore doesn't change in the range of pH value below 10. However, Ca^2+ and Mg^2+ may induce strong coagulation of particles when pH value is higher than 10. The adsorption of species of calcium and magnesium ions on diaspore can cause the compression of electric double layer, the decrease of the absolute value of zeta potential and the repulsion force between diaspore particles. The new IEP (isoelectric point) appeared at pH value of 11 may attribute to the adsorption of Mg(OH)2(s).展开更多
Poly(urea-formaldehyde)(PUF)microcapsules were prepared by in-situ polymerization with four different pro-cesses in this paper.The chemical composition,surface morphology,particle size distribution,and thermal sta-bil...Poly(urea-formaldehyde)(PUF)microcapsules were prepared by in-situ polymerization with four different pro-cesses in this paper.The chemical composition,surface morphology,particle size distribution,and thermal sta-bility were characterized by FTIR,SEM,particle size analyzer,and TGA,respectively.The results demonstrated that the agglomeration of the PUF microcapsules was related to the agglomeration of the emulsion particles caused by the changes of emulsion interface during the shell polymerization.Due to the slow deposition of the shell material,the PUF microcapsules with the core-shell structure prepared by the process with ammonium chloride as the last additive showed good dispersibility with an average diameter of 6.36μm,high core content of 71.3 wt%,and high yield of 61.3 wt%.The PUF microcapsules had good thermal stability below 216?C.The PUF microcapsules could be uniformly dispersed in the epoxy coating in a single form.The epoxy coating with 2 wt%PUF microcapsules showed good self-healing property,and the service life of the coating was about doubled.展开更多
A series of β-cyclodextrin (CDs) functionalized graphene nanohybrids have been successfully fabricated utilizing the classical covalent modification methods at different reaction temperatures. It is very interesti...A series of β-cyclodextrin (CDs) functionalized graphene nanohybrids have been successfully fabricated utilizing the classical covalent modification methods at different reaction temperatures. It is very interesting that although both CDs and graphene oxide (GO) could he easily decomposed, the effective combination of GO with CDs leads to significantly enhanced thermal stability of graphene derivatives (GO-CDs). Moreover, the introduction of CDs could dramatically improve the dispersibility promotion of our products in both polar/protic and nonpolar/aprotic solvents, which will contribute to the preparation of polymer nanocomposites and increase of their thermal stability. The improved thermal degradation temperatures can be obtained for polyvinyl alcohol after filling with as little as 1 wt.% of the hybrid. The obtained products could be potentially used in heat-retardant or thermal-control materials.展开更多
The present study describes the complexation between curcumin(Cur) and a peptide mixture(Pep). Pep was prepared by enzymatic hydrolysis of casein and used as an excipient for poorly water-soluble Cur. An aqueous solut...The present study describes the complexation between curcumin(Cur) and a peptide mixture(Pep). Pep was prepared by enzymatic hydrolysis of casein and used as an excipient for poorly water-soluble Cur. An aqueous solution of Pep and an acetone solution of Cur were mixed and lyophilized to obtain a white-yellow powder of the peptide and Cur complex(CurPep). The water dispersibility of Cur was enhanced by the complexation with Pep. Pep was fractionated using ammonium sulfate precipitation and ultrafiltration to identify which peptides preferentially interact with Cur. Relatively hydrophobic peptides with high molecular weights(>5 k Da) were more effective in enhancing the water dispersibility of Cur than other fractions. Cur-Pep dispersed under acidic and neutral conditions, at which amphoteric Pep is positively or negatively charged. Cur-Pep exists as a hydrocolloid with particle size 160–330 nm in aqueous media.展开更多
Nano-Fe3O4 particles were prepared by a two-step microemulsion method, the influence of molar ratio of water to NP-5 (R), alkali concentration and temperature on dispersibility and shape of the nanoparticles were disc...Nano-Fe3O4 particles were prepared by a two-step microemulsion method, the influence of molar ratio of water to NP-5 (R), alkali concentration and temperature on dispersibility and shape of the nanoparticles were discussed. Magnetic studies were also carried out using VSM in this paper. It was found that the optimum preparation parameters are R = 6.0, alkali concentration = 2.5 mol.L–1, initial total iron concentration as 0.88 mol.L–1, and the temperature being 30°C, the prepared nano magnetite particles have uniform size and good dispersibility with a crystal structure belonging to cubicFe3O4 and lattice parameters of a = 8.273 ?. The results of magnetic studies show, magnetic properties of particles are influenced by dispersibility of nanoparticles which depends on size of clusters. The better dispersibility of nanoparticles leads to more ordered inner magnetic vector, and so the stronger magnetic behavior of nano-Fe3O4 particles.展开更多
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
Good dispersibility of graphene in a medium or matrix is a critical issue in practical applications.In this work,graphene was functionalized using N-(4-hydroxyl phenyl)maleimide(4-HPM)via the Diels—Alder(DA)reaction ...Good dispersibility of graphene in a medium or matrix is a critical issue in practical applications.In this work,graphene was functionalized using N-(4-hydroxyl phenyl)maleimide(4-HPM)via the Diels—Alder(DA)reaction by a one-step catalyst-free approach.The optimal reaction condition was found to be 90℃for 12 h using dimethytformamide(DMF)as the solvent.FTIR,Raman spectroscopy,XPS and EDS proved that 4-HPM moieties were successfully grafted onto the surface of graphene.UVvis and TGA confirmed that the grafting amount of 4-HPM was 3.75%-3.97%based on the mass of graphene.Functionalized graphene showed excellent dispersion stability when dispersed in common solvents such as ethanol,DMF,water,tetrahydrofuran and pxylene.Meanwhile,functionalized graphene also exhibited pH sensitivity in aqueous due to the phenolic hydroxyls from the 4-HPM moieties.As a result of good dispersion stability and pH sensitivity,compared with graphene,functionalized graphene had better adsorption capacity for methylene blue(MB)from aqueous solution.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
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
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
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
Fine nickel powders with a narrow particle size distribution were prepared by reducing nickel hydroxide in aqueous solution.The formation and reduction pathways of nickel powder were analyzed,as well as the effects of...Fine nickel powders with a narrow particle size distribution were prepared by reducing nickel hydroxide in aqueous solution.The formation and reduction pathways of nickel powder were analyzed,as well as the effects of the molar ratio of hydrazine hydrate to nickel hydroxide,hydrazine concentration,and the dosage of surfactant PEG6000 on particle size,surface morphology,and dispersion.Results reveal that the nickel particle nucleation occurs on the nickel hydroxide surface,and the nickel hydroxide gradually dissolves during the reaction.With the increase in molar ratio of hydrazine hydrate to nickel hydroxide,the nickel particle size is initially decreased and then increased.Higher hydrazine hydrate concentrations result in smaller particle sizes.A small amount of PEG6000 surfactant can improve dispersion of nickel particles,but a higher amount of PEG6000 surfactant results in the maintenance of the morphology of nickel hydroxide.Adjusting the surfactant dosage can control the average particle size between 1-2μm.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
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
基金Project (2005CB623701) supported by the National Basic Research Program of China
文摘Dispersion experiments were conducted to study the influence of metallic cations on the dispersibility of diaspore. The reaction mechanisms were investigated based on the analysis of zeta (ξ) potential and calculations of solution chemistry and DLVO theory. The results show that the valence of cations, instead of the cation type, plays an important role in the dispersibility of diaspore The impact of multivalent metallic cations is greater than that of monovalent cations. In the presence of Ca^2+ and Mg^2+, the dispersion of diaspore doesn't change in the range of pH value below 10. However, Ca^2+ and Mg^2+ may induce strong coagulation of particles when pH value is higher than 10. The adsorption of species of calcium and magnesium ions on diaspore can cause the compression of electric double layer, the decrease of the absolute value of zeta potential and the repulsion force between diaspore particles. The new IEP (isoelectric point) appeared at pH value of 11 may attribute to the adsorption of Mg(OH)2(s).
基金This work was supported by the Jiangsu National Synergetic Innovation Center for Advanced Materials and the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Poly(urea-formaldehyde)(PUF)microcapsules were prepared by in-situ polymerization with four different pro-cesses in this paper.The chemical composition,surface morphology,particle size distribution,and thermal sta-bility were characterized by FTIR,SEM,particle size analyzer,and TGA,respectively.The results demonstrated that the agglomeration of the PUF microcapsules was related to the agglomeration of the emulsion particles caused by the changes of emulsion interface during the shell polymerization.Due to the slow deposition of the shell material,the PUF microcapsules with the core-shell structure prepared by the process with ammonium chloride as the last additive showed good dispersibility with an average diameter of 6.36μm,high core content of 71.3 wt%,and high yield of 61.3 wt%.The PUF microcapsules had good thermal stability below 216?C.The PUF microcapsules could be uniformly dispersed in the epoxy coating in a single form.The epoxy coating with 2 wt%PUF microcapsules showed good self-healing property,and the service life of the coating was about doubled.
基金supported by China Postdoctoral Science Foundation Funded Project(No.20100481146)Jiangsu Planned Projects for Postdoctoral Research Funds(No.1002015C)+2 种基金Natural Science Foundation of Jiangsu Province(No.BK2011712, BK20130575)National University Student Innovation Program(No.201210288036)NJUST Opening Measuring Fund of Large Precious Apparatus(No.2012-01-15)
文摘A series of β-cyclodextrin (CDs) functionalized graphene nanohybrids have been successfully fabricated utilizing the classical covalent modification methods at different reaction temperatures. It is very interesting that although both CDs and graphene oxide (GO) could he easily decomposed, the effective combination of GO with CDs leads to significantly enhanced thermal stability of graphene derivatives (GO-CDs). Moreover, the introduction of CDs could dramatically improve the dispersibility promotion of our products in both polar/protic and nonpolar/aprotic solvents, which will contribute to the preparation of polymer nanocomposites and increase of their thermal stability. The improved thermal degradation temperatures can be obtained for polyvinyl alcohol after filling with as little as 1 wt.% of the hybrid. The obtained products could be potentially used in heat-retardant or thermal-control materials.
文摘The present study describes the complexation between curcumin(Cur) and a peptide mixture(Pep). Pep was prepared by enzymatic hydrolysis of casein and used as an excipient for poorly water-soluble Cur. An aqueous solution of Pep and an acetone solution of Cur were mixed and lyophilized to obtain a white-yellow powder of the peptide and Cur complex(CurPep). The water dispersibility of Cur was enhanced by the complexation with Pep. Pep was fractionated using ammonium sulfate precipitation and ultrafiltration to identify which peptides preferentially interact with Cur. Relatively hydrophobic peptides with high molecular weights(>5 k Da) were more effective in enhancing the water dispersibility of Cur than other fractions. Cur-Pep dispersed under acidic and neutral conditions, at which amphoteric Pep is positively or negatively charged. Cur-Pep exists as a hydrocolloid with particle size 160–330 nm in aqueous media.
文摘Nano-Fe3O4 particles were prepared by a two-step microemulsion method, the influence of molar ratio of water to NP-5 (R), alkali concentration and temperature on dispersibility and shape of the nanoparticles were discussed. Magnetic studies were also carried out using VSM in this paper. It was found that the optimum preparation parameters are R = 6.0, alkali concentration = 2.5 mol.L–1, initial total iron concentration as 0.88 mol.L–1, and the temperature being 30°C, the prepared nano magnetite particles have uniform size and good dispersibility with a crystal structure belonging to cubicFe3O4 and lattice parameters of a = 8.273 ?. The results of magnetic studies show, magnetic properties of particles are influenced by dispersibility of nanoparticles which depends on size of clusters. The better dispersibility of nanoparticles leads to more ordered inner magnetic vector, and so the stronger magnetic behavior of nano-Fe3O4 particles.
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the National Natural Science Foundation of China(Grant No.51573211)for financial support.
文摘Good dispersibility of graphene in a medium or matrix is a critical issue in practical applications.In this work,graphene was functionalized using N-(4-hydroxyl phenyl)maleimide(4-HPM)via the Diels—Alder(DA)reaction by a one-step catalyst-free approach.The optimal reaction condition was found to be 90℃for 12 h using dimethytformamide(DMF)as the solvent.FTIR,Raman spectroscopy,XPS and EDS proved that 4-HPM moieties were successfully grafted onto the surface of graphene.UVvis and TGA confirmed that the grafting amount of 4-HPM was 3.75%-3.97%based on the mass of graphene.Functionalized graphene showed excellent dispersion stability when dispersed in common solvents such as ethanol,DMF,water,tetrahydrofuran and pxylene.Meanwhile,functionalized graphene also exhibited pH sensitivity in aqueous due to the phenolic hydroxyls from the 4-HPM moieties.As a result of good dispersion stability and pH sensitivity,compared with graphene,functionalized graphene had better adsorption capacity for methylene blue(MB)from aqueous solution.
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 National Key R&D Program of China(2021YFA1502802)the National Natural Science Foundation of China(U21B2092,22202213,22402210,22502215,22502214,22572200,and 22579171)+4 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 2025119The XAS experiments were conducted in Beijing Synchrotron Radiation Facility(BSRF)and Shanghai Synchrotron Radiation Facility(SSRF).
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National Natural Science Foundation of China(51704257,52174350)Hunan Provincial Science and Technology Innovation Program(2024AQ2039)。
文摘Fine nickel powders with a narrow particle size distribution were prepared by reducing nickel hydroxide in aqueous solution.The formation and reduction pathways of nickel powder were analyzed,as well as the effects of the molar ratio of hydrazine hydrate to nickel hydroxide,hydrazine concentration,and the dosage of surfactant PEG6000 on particle size,surface morphology,and dispersion.Results reveal that the nickel particle nucleation occurs on the nickel hydroxide surface,and the nickel hydroxide gradually dissolves during the reaction.With the increase in molar ratio of hydrazine hydrate to nickel hydroxide,the nickel particle size is initially decreased and then increased.Higher hydrazine hydrate concentrations result in smaller particle sizes.A small amount of PEG6000 surfactant can improve dispersion of nickel particles,but a higher amount of PEG6000 surfactant results in the maintenance of the morphology of nickel hydroxide.Adjusting the surfactant dosage can control the average particle size between 1-2μm.
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.