摘要:

A primary bacterial film on a metal surface immersed in natural waters can create electrochemical conditions at the base of the film that are radically different from those in the bulk water. The concentrations of dissolved oxygen and other chemical species; as well as pH at the metal surface are usually affected. These changes influence electrochemical reactions taking place on the metal during corrosion. On the other hand, the electrochemistry of corrosion can also change the pH and ionic concentrations at the metal surface, thus influencing biofilm formation. This paper will examine what types of changes take place under marine biofilms, the mechanisms by which these changes influence several types of corrosion on a variety of metals, and the implications of that influence to both corrosion rates and corrosion control.

ISSN:0892-7014    

DOI:10.1080/08927019309386247

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Biofilms were generated on the surfaces of heat‐treated or untreated mild steel coupons by incubating for 4 weeks with or without single or mixed inocula of the anaerobic sulphate‐reducing bacterium,Desulfovibrio desulfuricans, and the aerobic pseudomonad,Pseudomonasfluorescens. P. fluorescensbiofilms were scanty, comprising mainly of approximately circular groups of haematite crystals with bacterial cells (mean 102·67·cm−2) aggregating on and around them. On cleaned coupons, circular areas of corrosion corresponding to the crystalline clumps were observed.D. desulfuricansbiofilms were thicker and more uniform. They were composed of iron sulphide corrosion products, bacterial cells (104·33·cm−2) and large amounts of polysaccharide (EPS), seen in the scanning electron microscope. Mixed culture biofilms appeared similarly thick, but somewhat patchier. Cells ofD. desulfuricansand iron sulphide corrosion products were the main components. Cell populations were 101·69·cm−2forP. fluorescensand 104·21‐cm−2forD. desulfuricans. Somewhat less EPS was observed in the scanning electron microscope.

ISSN:0892-7014    

DOI:10.1080/08927019309386248

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Biofouling and corrosion products on 70/30 cupronickel exposed to polluted seawater were studied by SEM with EDAX analysis. Layers of corrosion products containing dissimilar levels of sulphide, iron, copper and nickel were detected. An outer porous layer covered by a biofilm was present in all samples. Only a few genera of diatoms and protozoa could be found in the biofilm. Biofilm establishment on cupronickel was delayed compared with other more inert materials previously assayed. Electrochemical measurements showed that sulphide ions affect cupronickel passivity, interfering in the formation of the outer passive layers.

ISSN:0892-7014    

DOI:10.1080/08927019309386249

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

This paper describes a new technique which used low levels of copper and chlorine to minimise biofouling of pipes and heat exchangers in ships, offshore structures and power stations. Very low concentrations of copper (5 μg · 1−1) and chlorine 20 μg · 1−1) act synergistically to prevent the growth of micro‐ and macrofouling organisms.

ISSN:0892-7014    

DOI:10.1080/08927019309386250

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

ISSN:0892-7014    

DOI:10.1080/08927019309386246

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor