As an effective conventional absorbent, biochar exhibited limited adsorption ability toward small hydrophobic molecules. To enhance the adsorption capacity, a novel adsorbent was prepared by immobilizing nanoscale zer...As an effective conventional absorbent, biochar exhibited limited adsorption ability toward small hydrophobic molecules. To enhance the adsorption capacity, a novel adsorbent was prepared by immobilizing nanoscale zero-valent iron onto modified biochar（MB） and then the elemental silver was attached to the surface of iron（Ag/Fe/MB）. It＇s noted that spherical Ag/Fe nanoparticles with diameter of 51 nm were highly dispersed on the surface of MB. As the typical hydrophobic contaminant, carbon tetrachloride was selected for examining the removal efficiency of the adsorbent. The removal efficiencies of carbon tetrachloride by original biochar（OB）, Ag/Fe, Ag/Fe/OB and Ag/Fe/MB were fully investigated. It＇s found that Ag/Fe/MB showed higher carbon tetrachloride removal efficiency, which is about 5.5 times higher than that of the OB sample due to utilizing the merits of high adsorption and reduction. Thermodynamic parameters revealed that the removal of carbon tetrachloride by Ag/Fe/MB was a spontaneous and exothermic process, which was affected by solution p H, initial carbon tetrachloride concentration and temperature. The novel Ag/Fe/MB composites provided a promising material for carbon tetrachloride removal from effluent.展开更多
Ag/Fe multilayers with well compositional modulation periodicity of 4-60 nm were prepared at room temperature by evaporation deposition using an ultra high vacuum (UHV) chamber. Their microstructure and hardness were ...Ag/Fe multilayers with well compositional modulation periodicity of 4-60 nm were prepared at room temperature by evaporation deposition using an ultra high vacuum (UHV) chamber. Their microstructure and hardness were investigated using XRD, TEM and nanoindentation. The fcc/bcc type multilayers show a textured polycrystalline growth with Ag (111) and Fe (110) in Ag layers and Fe layers, respectively. The hardness increases with decreasing periodicity and approaches the maximum of 6.36 GPa at the periodicity of 4 nm. The peak hardness is 1.51 times mixture value. The experimental results are well explained by the dislocation-image force-based model developed by Lehoczky.展开更多
The emergence of insecticide resistance presents a major challenge in pest control and agriculture,while the use of conventional pesticides raises environmental and health concerns.This study addresses these issues th...The emergence of insecticide resistance presents a major challenge in pest control and agriculture,while the use of conventional pesticides raises environmental and health concerns.This study addresses these issues through the green synthesis of Ag/Fe bimetallic nanoparticles(BMNPs)using Vallaris solanacea plant extract and evaluates their eco-biological activities.The synthesized Ag/Fe BMNPs,with an average size of 30 nm as determined by SEM,were characterized by UV–Vis spectroscopy,FTIR,EDX,and SEM.In vitro assays revealed significant anti-inflammatory(91%),antioxidant(95%),anti-diabetic,anti-hemolytic,and antimicrobial activities.Additionally,the nanoparticles demonstrated 100% mortality against Sitophilus oryzae(rice weevil)and exhibited 97%degradation of the pesticide Novacide,indicating potent pesticidal and environmental remediation capabilities.Computational analysis,including molecular docking and molecular dynamics simulations,revealed strong interactions between Ag/Fe BMNPs and insecticide resistance(IR)proteins,with binding energies surpassing those of traditional pesticides,suggesting an ability to circumvent resistance mechanisms.These findings highlight the potential of Ag/Fe BMNPs as a sustainable,eco-friendly alternative for pest management and environmental applications in agriculture and beyond.展开更多
Two important iron oxides： Fe304 and Fe203, as well as Fe304 and Fe203 nanoparticles mingling with Ag were successfully synthesized via a hydrothermal procedure. The samples were confirmed and characterized by X-ray ...Two important iron oxides： Fe304 and Fe203, as well as Fe304 and Fe203 nanoparticles mingling with Ag were successfully synthesized via a hydrothermal procedure. The samples were confirmed and characterized by X-ray diffraction （XRD）, and X-ray photoelectron spectroscopy （XPS）. The morphology of the samples was observed by transmission electron microscopy （TEM）. The results indicated Fe304, Fe203, Ag/Fe304 and Ag/Fe203 samples all were nanoparticles with smaller sizes. The samples were modified on a glassy carbon electrode and their elctrocatalytic properties for p-nitropbenol in a basic solution were investigated. The results revealed all the samples showed enhanced catalytic performances by comparison with a bare glassy carbon electrode. Furthermore, p-nitrophenol could be reduced at a lower peak potential or a higher peak current on a glassy carbon electrode modified with Ag/Fe304 or Ag/Fe203 composite nanoparticles.展开更多
（Ag ＋ Fe）-doped ZnO nanopowders have been synthesized using combustion method. Ag doping level was kept as 2 at.%, and Fe doping level was varied from 3 to 6 at,%, and the structural, optical, surface morphological...（Ag ＋ Fe）-doped ZnO nanopowders have been synthesized using combustion method. Ag doping level was kept as 2 at.%, and Fe doping level was varied from 3 to 6 at,%, and the structural, optical, surface morphological, and antibacterial properties have been investigated. The structural studies show that ZnO/（Ag 4-Fe） nanopowders have hexagonal wurtzite structure with a preferential orientation along the （101） plane. The FE-SEM images indicate that there is a gradual decrease in the grain size with the increase in the doping level of Fe, and the TEM images are correlated well with FE-SEM images. The XPS profile clearly confirms the presence of expected elemental composition. Photolumi- nescence studies reveal the presence of extrinsic defects in the material. Antibacterial activity of Ag- and Fe-doped ZnO nanopowders against Vibrio parahaemolyticus, Vibrio Cholerae, and Staphylococcus aureus bacteria was also investigated.展开更多
In this work,we fabricated three kinds of Ag/Fe2O3 model catalysts with different morphologies to study the interfacial interactions between Ag and Fe2O3,and how they affected the catalytic activity in hydrogenation o...In this work,we fabricated three kinds of Ag/Fe2O3 model catalysts with different morphologies to study the interfacial interactions between Ag and Fe2O3,and how they affected the catalytic activity in hydrogenation of p-nitrophenol was explored.The hydrothermal method was used to synthesize the metal oxide supported silver catalyst,with various morphologies including nanoplates(NPs),nanospheres(NSs),and nanocubes(NCs).The crystal structure,morphology and surface elements of the composite were investigated by various measurements,such as X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM)and X-ray photoelectron spectroscopy(XPS).The catalytic activity was also evaluated by the reduction of p-nitrophenol to p-aminophenol.It was found that the activities of the above catalysts varied with the morphology of the support.Among them,Ag/Fe2O3 NPs promoted the highest performance,Ag/Fe2O3 NSs were slightly inferior,and Ag/Fe2O3 NCs were the worst.At last,we ascribed the remarkable activity of Ag/Fe2O3 NPs to the strong metal-support interactions between Ag and Fe2O3.展开更多
基金supported by the National Natural Science Foundation of China(No.41472223)
文摘As an effective conventional absorbent, biochar exhibited limited adsorption ability toward small hydrophobic molecules. To enhance the adsorption capacity, a novel adsorbent was prepared by immobilizing nanoscale zero-valent iron onto modified biochar（MB） and then the elemental silver was attached to the surface of iron（Ag/Fe/MB）. It＇s noted that spherical Ag/Fe nanoparticles with diameter of 51 nm were highly dispersed on the surface of MB. As the typical hydrophobic contaminant, carbon tetrachloride was selected for examining the removal efficiency of the adsorbent. The removal efficiencies of carbon tetrachloride by original biochar（OB）, Ag/Fe, Ag/Fe/OB and Ag/Fe/MB were fully investigated. It＇s found that Ag/Fe/MB showed higher carbon tetrachloride removal efficiency, which is about 5.5 times higher than that of the OB sample due to utilizing the merits of high adsorption and reduction. Thermodynamic parameters revealed that the removal of carbon tetrachloride by Ag/Fe/MB was a spontaneous and exothermic process, which was affected by solution p H, initial carbon tetrachloride concentration and temperature. The novel Ag/Fe/MB composites provided a promising material for carbon tetrachloride removal from effluent.
基金Projects(50871060, 50772055) supported by the National Natural Science Foundation of ChinaProject(2007AA03Z426) supported by High-tech Research and Development Program of China
文摘Ag/Fe multilayers with well compositional modulation periodicity of 4-60 nm were prepared at room temperature by evaporation deposition using an ultra high vacuum (UHV) chamber. Their microstructure and hardness were investigated using XRD, TEM and nanoindentation. The fcc/bcc type multilayers show a textured polycrystalline growth with Ag (111) and Fe (110) in Ag layers and Fe layers, respectively. The hardness increases with decreasing periodicity and approaches the maximum of 6.36 GPa at the periodicity of 4 nm. The peak hardness is 1.51 times mixture value. The experimental results are well explained by the dislocation-image force-based model developed by Lehoczky.
文摘The emergence of insecticide resistance presents a major challenge in pest control and agriculture,while the use of conventional pesticides raises environmental and health concerns.This study addresses these issues through the green synthesis of Ag/Fe bimetallic nanoparticles(BMNPs)using Vallaris solanacea plant extract and evaluates their eco-biological activities.The synthesized Ag/Fe BMNPs,with an average size of 30 nm as determined by SEM,were characterized by UV–Vis spectroscopy,FTIR,EDX,and SEM.In vitro assays revealed significant anti-inflammatory(91%),antioxidant(95%),anti-diabetic,anti-hemolytic,and antimicrobial activities.Additionally,the nanoparticles demonstrated 100% mortality against Sitophilus oryzae(rice weevil)and exhibited 97%degradation of the pesticide Novacide,indicating potent pesticidal and environmental remediation capabilities.Computational analysis,including molecular docking and molecular dynamics simulations,revealed strong interactions between Ag/Fe BMNPs and insecticide resistance(IR)proteins,with binding energies surpassing those of traditional pesticides,suggesting an ability to circumvent resistance mechanisms.These findings highlight the potential of Ag/Fe BMNPs as a sustainable,eco-friendly alternative for pest management and environmental applications in agriculture and beyond.
文摘Two important iron oxides： Fe304 and Fe203, as well as Fe304 and Fe203 nanoparticles mingling with Ag were successfully synthesized via a hydrothermal procedure. The samples were confirmed and characterized by X-ray diffraction （XRD）, and X-ray photoelectron spectroscopy （XPS）. The morphology of the samples was observed by transmission electron microscopy （TEM）. The results indicated Fe304, Fe203, Ag/Fe304 and Ag/Fe203 samples all were nanoparticles with smaller sizes. The samples were modified on a glassy carbon electrode and their elctrocatalytic properties for p-nitropbenol in a basic solution were investigated. The results revealed all the samples showed enhanced catalytic performances by comparison with a bare glassy carbon electrode. Furthermore, p-nitrophenol could be reduced at a lower peak potential or a higher peak current on a glassy carbon electrode modified with Ag/Fe304 or Ag/Fe203 composite nanoparticles.
基金the financial assistance from the director of collegiate education,Govt.of Tamil Nadu,Chennai
文摘（Ag ＋ Fe）-doped ZnO nanopowders have been synthesized using combustion method. Ag doping level was kept as 2 at.%, and Fe doping level was varied from 3 to 6 at,%, and the structural, optical, surface morphological, and antibacterial properties have been investigated. The structural studies show that ZnO/（Ag 4-Fe） nanopowders have hexagonal wurtzite structure with a preferential orientation along the （101） plane. The FE-SEM images indicate that there is a gradual decrease in the grain size with the increase in the doping level of Fe, and the TEM images are correlated well with FE-SEM images. The XPS profile clearly confirms the presence of expected elemental composition. Photolumi- nescence studies reveal the presence of extrinsic defects in the material. Antibacterial activity of Ag- and Fe-doped ZnO nanopowders against Vibrio parahaemolyticus, Vibrio Cholerae, and Staphylococcus aureus bacteria was also investigated.
基金financially supported by the 111 Project of the Ministry of Science and Technology of China(No.B17019)Talent Project of Southwest University of the Ministry of Education of China(No.SWU115034)。
文摘In this work,we fabricated three kinds of Ag/Fe2O3 model catalysts with different morphologies to study the interfacial interactions between Ag and Fe2O3,and how they affected the catalytic activity in hydrogenation of p-nitrophenol was explored.The hydrothermal method was used to synthesize the metal oxide supported silver catalyst,with various morphologies including nanoplates(NPs),nanospheres(NSs),and nanocubes(NCs).The crystal structure,morphology and surface elements of the composite were investigated by various measurements,such as X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM)and X-ray photoelectron spectroscopy(XPS).The catalytic activity was also evaluated by the reduction of p-nitrophenol to p-aminophenol.It was found that the activities of the above catalysts varied with the morphology of the support.Among them,Ag/Fe2O3 NPs promoted the highest performance,Ag/Fe2O3 NSs were slightly inferior,and Ag/Fe2O3 NCs were the worst.At last,we ascribed the remarkable activity of Ag/Fe2O3 NPs to the strong metal-support interactions between Ag and Fe2O3.
