Microbial contamination and the resulting corrosion in aircraft fuel system pose a serious threat to flight safety.Revealing the corrosion behavior and mechanism of fuel-degrading microorganisms on tank materials is c...Microbial contamination and the resulting corrosion in aircraft fuel system pose a serious threat to flight safety.Revealing the corrosion behavior and mechanism of fuel-degrading microorganisms on tank materials is crucial for developing effective mitigation strategies.In this study,the corrosion mechanisms of two representative hydrocarbon-degrading bacteria,Alcanivorax dieselolei and Microbacterium oxydans,toward AA7075 aluminum alloy,were systematically investigated.A combination of biofilm characterization,electrochemical testing,and surface/corrosion product characterization was employed.Both strains markedly accelerated the corrosion of AA7075,as evidence by the progressive decrease in polarization resistance and the pronounced rightward shift of the potentiodynamic polarization curves.Moreover,the difference between the pitting potential(E_(pit))and the corrosion potential(E_(corr))(ΔE=E_(pit)‒E_(corr))decreased due to microbial activities,indicating a pronounced tendency toward accelerated pitting corrosion.Corrosion morphology analysis revealed that both microbes promoted localized pitting corrosion.Furthermore,analysis of aviation kerosene composition indicated that both bacteria accelerated the degradation of C8 and C9 alkanes.These findings highlight the multiple threats of microbial contamination,material degradation,and fuel quality deterioration in fuel systems and underscore the need for targeted protection strategies for marine aviation operations.展开更多
With the rapid development of the marine economy,marine microbiologically influenced corrosion(MIC)has garnered increasing attention.However,most studies have not analyzed the MIC process over continuous and extended ...With the rapid development of the marine economy,marine microbiologically influenced corrosion(MIC)has garnered increasing attention.However,most studies have not analyzed the MIC process over continuous and extended periods,failing to provide a comprehensive understanding of MIC mechanisms at different stages.In this study,the corrosion behavior of EH36 steel caused by Halomonas titanicae in an aerobic enriched seawater over a 30-d incubation period was investigated driven by big data.The results revealed that the corrosion by H.titanicae against EH36 steel evolved dynamically over time.During the initial stages,the aerobic respiration of H.titanicae consumed significant amounts of oxygen,which suppressed the cathodic oxygen reduction process,thereby inhibiting corrosion compared to the abiotic conditions.As time progressed,the accumulation of corrosion products slowed the abiotic corrosion,while the biotic corrosion accelerated due to a shift from aerobic to anaerobic respiration by H.titanicae,utilizing Fe0 and nitrate as electron donors and acceptors,respectively.The big data results are consistent with the weight loss and electrochemical data,demonstrating the reliability of using big data monitoring techniques to characterize microbial corrosion processes.展开更多
基金financially supported by the National Natural Science Foundation of China (No. 52371056)the Liaoning Provincial Youth Science Fund Project, China (Category B, No. 2025JH6/101000010)+1 种基金the Guangdong Basic and Applied Basic Research Foundation, China (No. 2024A1515240055)funding from the China Scholarship Council
文摘Microbial contamination and the resulting corrosion in aircraft fuel system pose a serious threat to flight safety.Revealing the corrosion behavior and mechanism of fuel-degrading microorganisms on tank materials is crucial for developing effective mitigation strategies.In this study,the corrosion mechanisms of two representative hydrocarbon-degrading bacteria,Alcanivorax dieselolei and Microbacterium oxydans,toward AA7075 aluminum alloy,were systematically investigated.A combination of biofilm characterization,electrochemical testing,and surface/corrosion product characterization was employed.Both strains markedly accelerated the corrosion of AA7075,as evidence by the progressive decrease in polarization resistance and the pronounced rightward shift of the potentiodynamic polarization curves.Moreover,the difference between the pitting potential(E_(pit))and the corrosion potential(E_(corr))(ΔE=E_(pit)‒E_(corr))decreased due to microbial activities,indicating a pronounced tendency toward accelerated pitting corrosion.Corrosion morphology analysis revealed that both microbes promoted localized pitting corrosion.Furthermore,analysis of aviation kerosene composition indicated that both bacteria accelerated the degradation of C8 and C9 alkanes.These findings highlight the multiple threats of microbial contamination,material degradation,and fuel quality deterioration in fuel systems and underscore the need for targeted protection strategies for marine aviation operations.
基金financially supported by the National Natural Science Foundation of China(Nos.U2106206,52471079,42276212,and 42176043)the Natural Science Foundation of Shandong Province(ZR2024ME047)+1 种基金the National Materials Corrosion and Protection Data Center(No.2023DATAFU20-01)The authors wish to acknowledge Sen Wang,Haiyan Yu,Xiaomin Zhao from State Key Laboratory of Microbial Technology,Shandong University for the assistance in the SEM analysis。
文摘With the rapid development of the marine economy,marine microbiologically influenced corrosion(MIC)has garnered increasing attention.However,most studies have not analyzed the MIC process over continuous and extended periods,failing to provide a comprehensive understanding of MIC mechanisms at different stages.In this study,the corrosion behavior of EH36 steel caused by Halomonas titanicae in an aerobic enriched seawater over a 30-d incubation period was investigated driven by big data.The results revealed that the corrosion by H.titanicae against EH36 steel evolved dynamically over time.During the initial stages,the aerobic respiration of H.titanicae consumed significant amounts of oxygen,which suppressed the cathodic oxygen reduction process,thereby inhibiting corrosion compared to the abiotic conditions.As time progressed,the accumulation of corrosion products slowed the abiotic corrosion,while the biotic corrosion accelerated due to a shift from aerobic to anaerobic respiration by H.titanicae,utilizing Fe0 and nitrate as electron donors and acceptors,respectively.The big data results are consistent with the weight loss and electrochemical data,demonstrating the reliability of using big data monitoring techniques to characterize microbial corrosion processes.