Most MIC studies have focused on bacterial involvement; however, under aerobic conditions, other single-celled organisms, such as fungi, yeast and diatoms, can influence corrosion. The predominant types of bacteria associated with MIC are sulfate-reducing bacteria (SRB), sulfur-oxidizing bacteria, iron-oxidizing/reducing bacteria, manganese oxidizing bacteria, and bacteria secreting organic acids and slime. These organisms coexist within a biofilm matrix on metal surfaces, functioning as a consortium in a complex and coordinated manner. The various mechanisms of biocorrosion reflect the variety of physiological activities carried out by these different types of microorganisms when they coexist in biofilms. Despite decades of study on MIC, it is still not known with certainty how many species of microorganisms contribute to corrosion, and researchers continue to report on the formation of biofilms by an ever-widening range of microbial species.
9. Give English equivalents to the following word combinations and learn them by heart:
деятельность микроорганизмов
различные среды
электрохимический процесс
органическая кислота
металлическая поверхность
сероокисляющие бактерии
образование биопленок
микробные виды
аэробные условия
синтетическая коррозия
10. Give Russian equivalents to the following word combinations and learn them by heart:
inhibit corrosion
entire surface
organic acid
hydrogen sulfide
manganese oxidizing bacteria
predominant type
biofilm matrix
physiological activities
11. Translate the following sentences into Russian.
1. Some bacteria can directly reduce metal atoms to ions.
2. Hydrogen ions are produced, along with hydroxyl ions, by the breakdown of water, and the electrons to form atomic hydrogen from the hydrogen ion are produced by the oxidation of atomic iron.
3. The source of electrons is the oxidation of the metal while the electron sink is reduction of hydrogen ions.
4. MIC has been observed as one of the major causes of underground pipeline corrosion.
5. Sulphate reducing bacteria (SRB) have been reported to be responsible for extensive corrosion in hydrocarbon industry.
6. There are other types of corrosion-enhancing bacteria such as iron-reducing bacteria, iron-oxidizing bacteria, nitrifying bacteria, methanogenic bacteria and so on.