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
The effect of low concentrated green inhibitors based on Ce-adipate and Ce-chloride on the corrosion of 7075 aluminum alloy in neutral NaCl electrolyte was studied.Corrosion studies were carried out using electrochemi...The effect of low concentrated green inhibitors based on Ce-adipate and Ce-chloride on the corrosion of 7075 aluminum alloy in neutral NaCl electrolyte was studied.Corrosion studies were carried out using electrochemical impedance spectroscopy(EIS)and linear sweep voltammetry(LSV)while scanning electron microscopy(SEM)and X-ray photoelectron spectroscopy(XPS)were used to conduct surface studies of the alloy upon immersion in the corrosion media.The electrochemical experiments reveal a better inhibitory effect of Ce-adipate than Ce-chloride owing to a higher polarization resistance value(about two times),and a lower corrosion current density.However,both inhibitors act as cathodic inhibitors,show high resistance to pitting corrosion,and enable sufficient protection during prolonged immersion(240 h)in corrosion media.The XPS analysis confirms the presence of cerium in the oxidation states of Ce(III)and Ce(IV)together with the carboxylate-COO−groups and C-C and C-H bonds on the tested specimen with Ce-adipate inhibitor,which are connected to the increased anti-corrosion efficiency.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 Ministry of Science,Technological Development and Innovation of the Republic of Serbia(Nos.451-03-66/2024-03/200026,451-03-65/2024-03/200135)。
文摘The effect of low concentrated green inhibitors based on Ce-adipate and Ce-chloride on the corrosion of 7075 aluminum alloy in neutral NaCl electrolyte was studied.Corrosion studies were carried out using electrochemical impedance spectroscopy(EIS)and linear sweep voltammetry(LSV)while scanning electron microscopy(SEM)and X-ray photoelectron spectroscopy(XPS)were used to conduct surface studies of the alloy upon immersion in the corrosion media.The electrochemical experiments reveal a better inhibitory effect of Ce-adipate than Ce-chloride owing to a higher polarization resistance value(about two times),and a lower corrosion current density.However,both inhibitors act as cathodic inhibitors,show high resistance to pitting corrosion,and enable sufficient protection during prolonged immersion(240 h)in corrosion media.The XPS analysis confirms the presence of cerium in the oxidation states of Ce(III)and Ce(IV)together with the carboxylate-COO−groups and C-C and C-H bonds on the tested specimen with Ce-adipate inhibitor,which are connected to the increased anti-corrosion efficiency.
