应用丝束电极研究了半连续培养基中SRB及其生物膜对Q235 低碳钢腐蚀的影响.采用电位、电流以及阻抗扫描技术测试了生物膜的不均匀性特性，以及 电极开路电位和电化学阻抗谱(EIS)与培养时间的关系.发现随生物膜的成长，开路电位负 移.由于生物膜中SRB代谢产生的硫化物具有导电性，使表面电位扫描已不能作为生物膜下 局部腐蚀的判据，但表面阻抗扫描却可探测到膜下的局部腐蚀.EIS表明，生物膜电容极大( 104～105 μF/cm2)，且膜电容随时间呈S型增加,而溶液电阻和电荷传递电阻则呈指 数下降.
Wire beam electrode(WBE) was applied to study the m icrobiologically influenced corrosion(MIC) of Q235 carbon steel associated with sulphate reducing bacteria(SRB) in semicontinuous culture medium(to be complete ly refreshed every 72 hours).The potential,galvanic current density and impedanc e mapping,as well as open circuit potential(OCP) and electrochemical impedance s pectrum(EIS) were measured to predict the localized corrosion under biofilm duri ng SRB growing.As a result,the OCP moved negatively gradually with time.However, The mapping showed the potential fluctuation on the WBE surface decreased over t ime due to the conductivity of FeSx(x=0.9～2) metabolized by SRB in th e biofilm.Therefore,the potential mapping could not be a criterion of localized corrosion under biofilm.Instead,the impedance mapping could give a good predicti on to the MIC.In addition,The biofilm capacity moved up to a very large level(～ 105 μF/cm2) in shape of sigmoid when SRB grew.At the same time,both solutio n resi〖JP2〗stance and charge transfer resistance decreased exponentially.〖JP 〗
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