微生物对金属的腐蚀和对有机材料的分解

Microbial Corrosion of Metals and Deterioration of Polymeric Materials

微生物（包括细菌和真菌）在金属的腐蚀和高分子材料的退化（分解）中起着重要的作用。在自然条件下，材料的表面附着薄薄的一层微生物，也叫微生物膜。微生物在材料表面上的生长直接影响到金属材料的电化学特征，可促进和加速其腐蚀速度；其它的微生物腐蚀反应包括有微生物体外多聚物，微生物产生的氢气和真菌分泌的有机酸类。异养型的细菌可直接或间接地分解高分子聚合物，将其做为自身的碳和能量来源，其结果是造成高分子材料结构的破坏。自养和异养型微生物都能通过分泌无机酸和参予硫化物的转化而破坏水泥和石质材料。生物降解和退化的防治通常是采用添加杀菌剂的办法，可是细菌能在与药物接触后的短时间内获得抵抗力。所以，防止材料腐蚀和退化的关键是防止和阻碍微生物的附着和生长，从而减轻和延缓破坏性。

Microorganisms including bacteria and fungi play an important role in the corrosion of metals and deterioration of polymeric materials Under natural conditions, a thin layer of microorganisms may adhere on surfaces forming the socalled biofilm Microbial colonization on surfaces influences the localized electrochemical characteristics of the metals, resulting in corrosion Other microbial processes inducing corrosion include microbial exopolymeric materials, microbial hydrogen and organic acids produced by the fungi Heterotrophic microorganisms utilize polymers either directly or indirectly as a source of carbon and energy, and the consequences are weakening of the polymer structure Both autotrophic and heterotrophic microorganisms are capable of deteriorating concrete and stone through production of inorganic acids and sulfur transformation respectively Prevention of biodeterioration is largely done by incorporation of biocides, but bacteria develop resistance quickly by mutation after exposure