The design of nanostructured materials occupies a privileged position in the development and management of affordable and effective technology in the antibacterial sector.Here,we discuss the antimicrobial properties o...The design of nanostructured materials occupies a privileged position in the development and management of affordable and effective technology in the antibacterial sector.Here,we discuss the antimicrobial properties of three carbonaceous nanoblades and nanodarts materials of graphene oxide(GO),reduced graphene oxide(RGO),and single-wall carbon nanotubes(SWCNTs)that have a mechano-bactericidal effect,and the ability to piercing or slicing bacterial membranes.To demonstrate the significance of size,morphology and composition on the antibacterial activity mechanism,the designed nanomaterials have been characterized.The minimum inhibitory concentration(MIC),standard agar well diffusion,and transmission electron microscopy were utilized to evaluate the antibacterial activity of GO,RGO,and SWCNTs.Based on the evidence obtained,the three carbonaceous materials exhibit activity against all microbial strains tested by completely encapsulating bacterial cells and causing morphological disruption by degrading the microbial cell membrane in the order of RGO>GO>SWCNTs.Because of the external cell wall structure and outer membrane proteins,the synthesized carbonaceous nanomaterials exhibited higher antibacterial activity against Gram-positive bacterial strains than Gram-negative and fungal microorganisms.RGO had the lowest MIC values(0.062,0.125,and 0.25 mg/mL against B.subtilis,S.aureus,and E.coli,respectively),as well as minimum fungal concentrations(0.5 mg/mL for both A.fumigatus and C.albicans).At 12 hr,the cell viability values against tested microbial strains were completely suppressed.Cell lysis and death occurred as a result of severe membrane damage caused by microorganisms perched on RGO nanoblades.Our work gives an insight into the design of effective graphene-based antimicrobial materials for water treatment and remediation.展开更多
Currently,as the production of light crude oil is reaching its peak,the focus of the petroleum industry is shifting towards significant amount of heavy oil to meet the increasing need for energy and fuels.Heavy oil is...Currently,as the production of light crude oil is reaching its peak,the focus of the petroleum industry is shifting towards significant amount of heavy oil to meet the increasing need for energy and fuels.Heavy oil is typically categorized by its high density,great viscosity with small API gravity,high hetero-atom content and limited low boiling point fuel fraction yield compared to light oil.One approach for enhancing the flow characteristics of heavy oil before the recovery process is introducing catalysts into the reservoir.This scientific research focuses on the preparation and characterization of(10%,20%,30%)TiO_(2)@α-Fe_(2)O_(3) nanocomposite catalysts for potential catalytic applications.The study outlines the synthesis method used to create different ratios of as-prepared nanocomposites.It provides detailed characterization through various analytical techniques.The results highlight the successful formation of X%TiO_(2)@α-Fe_(2)O_(3) nanocomposites with well-defined structures and optimized properties for catalytic reactions.The study investigates the impact of this nanocomposite on the rheological characterizations of heavy crude oil,focusing on the capability of decreasing viscosity and advance flow characteristics.The experimental results demonstrate notable improvements in viscosity reduction and enhancing heavy crude oil production processes as the best results obtained by(0.5 wt%)20%TiO_(2)@α-Fe_(2)O_(3)(62.6%after 2 h at 200°C).The asphaltene and resin ratio decreased by 54.5%and 68.1%respectively.The saturated and aromatic content shows 67.56%and 15.91%respectively at the same conditions.The presence of different surfactants(non-ionic and anionic)gives a synergetic effect which reveals active participation of contact angle changing and Interfacial tension(IFT)reduction.This research contributes to the advancement of methods for upgrading heavy crude oil,offering a promising avenue for increasing efficiency and productivity in the oil industry.展开更多
基金supported by the Center for Functional Materials,National Institute for Materials Science,Japan,Egyptian Petroleum Research Institute,Egypt,and Nano-Environmental Uint,Theodor Bilharz Research Institute,Egypt。
文摘The design of nanostructured materials occupies a privileged position in the development and management of affordable and effective technology in the antibacterial sector.Here,we discuss the antimicrobial properties of three carbonaceous nanoblades and nanodarts materials of graphene oxide(GO),reduced graphene oxide(RGO),and single-wall carbon nanotubes(SWCNTs)that have a mechano-bactericidal effect,and the ability to piercing or slicing bacterial membranes.To demonstrate the significance of size,morphology and composition on the antibacterial activity mechanism,the designed nanomaterials have been characterized.The minimum inhibitory concentration(MIC),standard agar well diffusion,and transmission electron microscopy were utilized to evaluate the antibacterial activity of GO,RGO,and SWCNTs.Based on the evidence obtained,the three carbonaceous materials exhibit activity against all microbial strains tested by completely encapsulating bacterial cells and causing morphological disruption by degrading the microbial cell membrane in the order of RGO>GO>SWCNTs.Because of the external cell wall structure and outer membrane proteins,the synthesized carbonaceous nanomaterials exhibited higher antibacterial activity against Gram-positive bacterial strains than Gram-negative and fungal microorganisms.RGO had the lowest MIC values(0.062,0.125,and 0.25 mg/mL against B.subtilis,S.aureus,and E.coli,respectively),as well as minimum fungal concentrations(0.5 mg/mL for both A.fumigatus and C.albicans).At 12 hr,the cell viability values against tested microbial strains were completely suppressed.Cell lysis and death occurred as a result of severe membrane damage caused by microorganisms perched on RGO nanoblades.Our work gives an insight into the design of effective graphene-based antimicrobial materials for water treatment and remediation.
基金[Egyptian Petroleum Research Institute] for their invaluable support and assistance in conducting this research
文摘Currently,as the production of light crude oil is reaching its peak,the focus of the petroleum industry is shifting towards significant amount of heavy oil to meet the increasing need for energy and fuels.Heavy oil is typically categorized by its high density,great viscosity with small API gravity,high hetero-atom content and limited low boiling point fuel fraction yield compared to light oil.One approach for enhancing the flow characteristics of heavy oil before the recovery process is introducing catalysts into the reservoir.This scientific research focuses on the preparation and characterization of(10%,20%,30%)TiO_(2)@α-Fe_(2)O_(3) nanocomposite catalysts for potential catalytic applications.The study outlines the synthesis method used to create different ratios of as-prepared nanocomposites.It provides detailed characterization through various analytical techniques.The results highlight the successful formation of X%TiO_(2)@α-Fe_(2)O_(3) nanocomposites with well-defined structures and optimized properties for catalytic reactions.The study investigates the impact of this nanocomposite on the rheological characterizations of heavy crude oil,focusing on the capability of decreasing viscosity and advance flow characteristics.The experimental results demonstrate notable improvements in viscosity reduction and enhancing heavy crude oil production processes as the best results obtained by(0.5 wt%)20%TiO_(2)@α-Fe_(2)O_(3)(62.6%after 2 h at 200°C).The asphaltene and resin ratio decreased by 54.5%and 68.1%respectively.The saturated and aromatic content shows 67.56%and 15.91%respectively at the same conditions.The presence of different surfactants(non-ionic and anionic)gives a synergetic effect which reveals active participation of contact angle changing and Interfacial tension(IFT)reduction.This research contributes to the advancement of methods for upgrading heavy crude oil,offering a promising avenue for increasing efficiency and productivity in the oil industry.
