Nos communications orales

Rechercher une publication :

Titre : Biocorrosion – Corrosion Influencée ou Induite par les Micro-organismes	Année : 2010
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : A study performed in 1990-1993 estimated a minimum of 12-13% of European harbours affected by a particularly aggressive localized MIC phenomenon, called Accelerated Low Water Corrosion (ALWC) occurring at or below the low water zone of steel waterfront structures. ALWC is well recognized to affect harbours worldwide, causing drastic reductions of the service life of steel structures due to unusual high corrosion rates. Prevention and mitigation solutions exist, but are costly, while ALWC prediction has so far not been possible due to the lack of understanding of abiotic and biotic factors and of the mechanisms involved. Presence and potential implication of sulfate-reducing and other sulfur bacteria in ALWC has been reported in previous studies. However, the mechanisms and the characteristics of the biofilm- deposit complex involved in ALWC remain unclear. The objective of this study is to obtain a detailed characterization of ALWC biofilm- deposit complexes taken from one European harbour in order to propose interaction and corrosion mechanisms. Several samples of corroded and non-corroded zones were recently taken from a European harbour affected by ALWC since 20 years. These samples were studied using different analytical methods: (1) cultivation targeting for the first time almost all MIC associated-bacterial metabolic groups (sulfate-reducing bacteria (SRB), thiosulfate-reducing bacteria (TRB), thiosulfate-oxidizing bacteria (TOB), iron- oxidizing bacteria (IOB), iron-reducing bacteria (IRB), manganese-reducing bacteria (MnRB) and marine aerobic heterotrophic bacteria); (2) 16S rDNA PCR-DGGE fingerprinting methods, (3) microscopic methods (e.g. SEM) and (4) analytical methods to determine chemical composition (i.e. XRD, XRFS, and Raman spectrometry). All targeted bacterial groups could be enriched from samples originating from ALWC and from the reference sites confirming that the presence of specific metabolic groups is not an exclusive criterion for characterizing ALWC biofilm. However, IOB activities appeared to be higher in ALWC than in reference samples indicating a potential implication of this metabolic group, which was not yet considered in ALWC. Analysis of SRB and TRB enrichments indicated specific populations associated with ALWC. Analysis of the different layers of biofilm-deposit complexes indicated the presence of an oxygen gradient within the biofilm/deposit complexes. Green rust and iron sulfide detected with SRB in the inner layers of ALWC samples indicated the occurrence of SRB activities. Further results and their interpretation will be discussed in the future to improve ALWC diagnostics and prediction. The work was carried out with a financial grant from the Research Fund for Coal and Steel of the European Community (Project number: RFSR-CT-2008-00018). EUROCORR - Journée de l’Institut de soudure Date : 18 juin 2010

Titre : Comportement des aciers inoxydables exposés en milieu marin	Année : 2009
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible lundi de la mécanique - CETIM

Titre : Installation véhiculant ou stockant de l'eau - Matériaux & Corrosion	Année : 2009
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible USIDO

Titre : The study of relationship between diversity of bacterial biofilms and marine corrosion of carbon steel in harbour environments	Année : 2008
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Here is reported investigation aimed to elucidate relationship between accelerated marine corrosion of carbon steel and community structure of bacterial biofilms associated with corrosion products. The study was conducted in three different French coastal regions (English Channel, Atlantic Ocean and Mediterranean Sea). SEM-EDX, ICP-AES, XRD and micro-Raman spectrometry revealed stratification of corrosion products based on iron oxidation state, regardless of geographical location. Molecular biology techniques and standard cultivation methods demonstrated that bacteria in corrosion products were abundant and highly diverse. Moreover, corrosion products contained many species of diatoms and multicellular organisms. Characterisation of cultivable bacteria and culture-independent molecular fingerprinting method (CE-SSCP) revealed more than 20 bacterial ribotypes in the deposits. Molecular detection of sulphate-reducing bacteria (SRB) was carried out using dissimilatory sulfite-reductase gene (dsrAB) and 16S rDNA probes specific for six SRB sub-groups. The results of microbiological analysis demonstrated that the composition and diversity of bacterial populations associated with corrosion products are determined by the chemistry of different regions, i.e. steel surface, corrosion product surface and green rust / oxy-hydroxide interface, without clear stratification. Moreover, the study confirmed that, irrespective of the site investigated, bacterial species detected in corrosion products differed from the ones present in bulk water, thus emphasising the importance of biofilm sampling when investigating corrosion failures. In view of the obtained results, the role of green rust as sulphate reservoir, the localised acidification induced by biogenically produced sulphur, the plausible role of extracellular polymeric substances in connecting bacterial cells and mineral corrosion products and the impact of multicellular organisms on the corrosion product stability are discussed. 14th International Congress on Marine Corrosion and Fouling July 27-31, 2008 Kobe, Japan

Titre : The study of relationship between diversity of bacterial biofilms and marine corrosion of carbon steel in harbour environments	Année : 2008
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Here is reported investigation aimed to elucidate relationship between accelerated marine corrosion of carbon steel and community structure of bacterial biofilms associated with corrosion products. The study was conducted in three different French coastal regions (English Channel, Atlantic Ocean and Mediterranean Sea). SEM-EDX, ICP-AES, XRD and micro-Raman spectrometry revealed stratification of corrosion products based on iron oxidation state, regardless of geographical location. Molecular biology techniques and standard cultivation methods demonstrated that bacteria in corrosion products were abundant and highly diverse. Moreover, corrosion products contained many species of diatoms and multicellular organisms. Characterisation of cultivable bacteria and culture-independent molecular fingerprinting method (CE-SSCP) revealed more than 20 bacterial ribotypes in the deposits. Molecular detection of sulphate-reducing bacteria (SRB) was carried out using dissimilatory sulfite-reductase gene (dsrAB) and 16S rDNA probes specific for six SRB sub-groups. The results of microbiological analysis demonstrated that the composition and diversity of bacterial populations associated with corrosion products are determined by the chemistry of different regions, i.e. steel surface, corrosion product surface and green rust / oxy-hydroxide interface, without clear stratification. Moreover, the study confirmed that, irrespective of the site investigated, bacterial species detected in corrosion products differed from the ones present in bulk water, thus emphasising the importance of biofilm sampling when investigating corrosion failures. In view of the obtained results, the role of green rust as sulphate reservoir, the localised acidification induced by biogenically produced sulphur, the plausible role of extracellular polymeric substances in connecting bacterial cells and mineral corrosion products and the impact of multicellular organisms on the corrosion product stability are discussed. 14th International Congress on Marine Corrosion and Fouling July 27-31, 2008 Kobe, Japan

Titre : Biofilm et matériaux : je t’aime moi non plus ». XIème colloque du Groupe Français de Bioélectrochimie	Année : 2008
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : A une époque où la tendance serait à la stérilisation généralisée, les biofilms sont souvent une source de problèmes sanitaires et industriels, liés à des effets toxiques mais également à des impacts sur les infrastructures (modification des propriétés de surface ou corrosion par exemple). Ces communautés biologiques, de l’échelle micrométrique à centimétrique selon la thématique (biofilms bactériens ou évolution en macro-biofilms pluricellulaires), présentent une affinité toute particulière pour la plupart des matériaux, métalliques ou non. Il s’agit donc d’un processus normal, naturel et généralement bénéfique d’un point de vue écologique. Néanmoins, bien que les matériaux soient conçus pour résister à un environnement donné, les micro-organismes viennent fréquemment perturber le sommeil des gestionnaires de ces structures. Difficiles à modéliser, à prédire et à maîtriser, que ce soit pour l’expérimentation scientifique ou pour le suivi industriel, ces interactions entre biofilms et matériaux concernent tous les domaines de compétences mais principalement la science des matériaux, la microbiologie et l’électrochimie. Cette communication pluridisciplinaire, parfois laborieuse, offre de nombreuses perspectives de recherche. Une partie de cette problématique est illustrée par des exemples issus de cas industriels, particulièrement en eau de mer, où la distinction des frontières minéral/organique et bénéfique/préjudiciable est discutée. Lacanau-Océan, 29 septembre - 2 octobre 2008

Titre : Sulfate reducing microorganisms: microorganisms implicated in heavy metals speciation and biocorrosion process in coastal and estuarial environments	Année : 2007
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible Annual conference of Universidad Católica de Chile, Santiago du Chili, 19 juillet 2007

Titre : Sulfate reducing microorganisms: microorganisms implicated in heavy metals speciation and biocorrosion process in coastal and estuarial environments	Année : 2007
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible Annual conference of Universidad Católica de Chile, Santiago du Chili, 19 juillet 2007

Titre : Corrosion deposits in natural seawater: a habitat with constant mineral organization and high micro-organisms diversity	Année : 2007
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Investigations into chemistry and microbiology of deposits formed during marine corrosion processes on surfaces of carbon steel are scarce. During the last decade a small number of in situ studies, mainly related to accelerate corrosion reported in harbour environments, has been carried out in Europe, Australia and Asia. Specific corrosion products, such as iron-sulphides in black liquid localized in the internal layer (steel side) or magnetite and iron oxy-hydroxides in external layer (seawater side), were found across the thickness of the deposit. However, the formation and the type of minerals, e.g. iron sulphide species and green rusts were not clearly identified. In this study, the structural organization and the composition of corrosion deposits formed on steel piling structures in three French ports in the English Channel, Atlantic Ocean and Mediterranean Sea have been determined. Spatial distribution of corrosion products did not differ between the three sites and it was strongly correlated with steel corrosion behaviour in saline electrolyte. The weight of the inorganic (mineral) fraction in corrosion products was frequently less than 50% (w/v) of the total weight; the other fraction being composed of water, organic compounds and micro-organisms. Bacterial diversity in the deposit was investigated using cultivable and molecular fingerprinting methods. High abundance and diversity was found in the three sites, with slight differences between surface and interface layers. The results indicate that corrosion deposits can be regarded as habitats with constant mineral fraction and stratification dependent on and following iron oxidation state. The composition and diversity of bacterial populations associated with corrosion products are determined by the chemistry of different regions, i.e. steel surface, deposit surface and green rust / oxy-hydroxide interface without clear stratification. The study confirmed that bacterial species detected in corrosion products differed from the ones present in bulk water, thus emphasising the importance of biofilm sampling when investigating corrosion failures. International conference on biocorrosion of materials (Biocorys 2007), 11-14 June 2007, Paris

Titre : Biocorrosion des matériaux métalliques	Année : 2007
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible Journée membres Institut de Soudure, Corrosion des aciers. 22 mars 2007, Villepinte

Titre : Electrochemical study of indoor atmospheric corrosion layers formed on ancient iron artefacts	Année : 2006
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : The degradation of iron-based materials by atmospheric corrosion is a well-know problem that may have incidence, especially for the storage of radioactive nuclear wastes. It is of importance to evaluate the damages due to this kind of corrosion within long time-periods. Atmospheric corrosion is thought to be a cycling process for which some parts of the corrosion layer may play a key role of electron acceptor during the wet periods. Studying atmospheric corrosion layers formed on ancient iron coupons provides helpful information on this phenomenon. Several indoor atmospheric corrosion layers (0-800 years old), were selected from different localizations in France. Each sample was scrapped from its iron substrate. The resulting powder was mixed with graphite in appropriate proportions and the mixture was pressed onto a stainless steel grid to constitute a composite electrode. The electrochemical responses of the different samples were recorded under galvanostatic regulation, in a nearneutral pH-buffered NaCl solution at 25°C. The E-t reduction curves allowed the determination of two characteristic parameters, Et / 2 , the potential value obtained at half the transition time, and Qt , the coulombic charge obtained at the end of the reduction. The diminution of Et / 2 and Qt with the age of the corrosion layer showed that the “reduction reactivity” decreases with time, suggesting a progressive stabilisation of the corrosion layer. In a second part of the work, we synthesised several common ferric or ferrous/ferric products (goethite, lepidocrocite, magnetite, maghemite, ferrihydrite) and compared their reduction responses (product alone or mixture of 2 or 3 products) to those of corrosion samples. EMCR

Titre : Approches méthodologiques pour la caractérisation des populations dominantes de biofilms marins naturels, sur acier au carbone	Année : 2005
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible 7ème forum de biodétérioration des matériaux, Ouistreham, 26-27 mai 2005

Titre : Long term atmospheric corrosion mechanisms : characterization of ancient rust scales on archaeological iron artifacts	Année : 2005
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible Eurocorr

Titre : Etude du comportement électrochimique d’oxydes/hydroxydes de fer par microbalance à quartz	Année : 2005
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible JE

Titre : Biofilm, biocorrosion and ALWC study in French port environment through in situ tests	Année : 2004
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Microbiologically Influenced Corrosion (MIC) of carbon steel construction is widely observed in port environment in tidal and immersion zone. In the case of low water zone of microorganisms in the Accelerated Low Water Corrosion (ALWC) phenomena the influence has been identified. Most French laboratories, industrials and ports cooperate in research programs to study the bacterial consortia of marine biofilm on carbon steel surface. This study is conducted in laboratory for the fundamental approaches, but the applied approach is conducted through in situ tests in port environment in Atlantic Ocean, English Channel and Mediterranean Sea. This experimental system is developed for investigations in tidal and low water zone, with and without cathodic protection (permanent, after pre-colonization, with failure simulation). The research objectives are: to develop analytic methods, to estimate the most dangerous biofilm consortia, to estimate some risk factors for corrosive metabolism, and to estimate a prevention plan for port authorities. Port and Terminal Technology – millennium conferences, Amsterdam

Titre : Utilisation de la microbalance à quartz pour l’étude des HDL de type rouille verte	Année : 2004
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible GFECI

Titre : Electrochemical study of lepidocrocite reduction and redox cycling for the mechanistic modelling of atmospheric corrosion	Année : 2004
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible Eurocorr

Titre : Applications of thin layers of iron oxidation products for corrosion studies	Année : 2004
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible Eurocorr

Titre : Interrelationship between cathodic protection and microbiologically influenced corrosion in marine environment: brief-review and prospects	Année : 2003
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Cathodic protection is widely used to prevent corrosion of steel constructions exposed to seawater. This protection causes a calcareous deposit as well as a biofilm formation. The Sulphate-Reducing Bacteria (SRB) and Thiosulphate-Reducing Bacteria (TRB) are involved in the steel biodegradation phenomena in marine environment. The surface colonization by these species under cathodic protection are described particularly for the TRB and with immersion periods of over 30 days. After a brief-review, preliminary studies explain the first results of our investigation in natural seawater and carbon steel during 4 to 8 weeks experiment. We have made experiments with natural strains of SRB/TRB, with monoculture of Desulfovibrio halophilus (SRB) and Dethiosulfovibrio peptidovorans (TRB), with potential a Cathodic Protection (CP) of –900 mV/SCE and –1000 mV/SCE and without CP. These results seem indicate that the effects of CP on the sulphide-producing bacteria metabolism is the reduction of their corrosive activity. Harbour Congress Proceeding, Antwerpen-Belgium, March-April 2003. Proceedings p.169-178

Titre : Impact de la protection cathodique sur l’activité corrosive de la flore sulfurogène	Année : 2003
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : La protection cathodique (PC) de l’acier au carbone en milieu marin est connue pour son effet inhibiteur vis-à-vis de la colonisation des genres bactériens aérobies [1]. En revanche, il a été démontré qu’un potentiel compris entre -900 mV/ECS et -1000 mV/ECS (généralement appliqué en zones portuaires françaises) est sans effet limitant vis-à-vis de la colonisation de la flore anaérobie de type sulfurogène telles que les Bactéries Sulfato-Réductrices (BSR) et Thiosulfato-Réductrices (BTR) [2][3][4][5]. Lors d’essais en laboratoire, il a été démontré que la rupture du système de PC accélère les phénomènes de biodétérioration, alors que ceux-ci semblent inhibés en temps normal [3][6]. Par conséquent, la PC modifierait le métabolisme bactérien et/ou l’action du produit du métabolisme bactérien. Plusieurs hypothèses sont émises, notamment le rôle de l’hydrogénase et l’inhibition de l’action des sulfures. 6ème forum de biodétérioration des matériaux, La Rochelle, 23-24 octobre 2003

Titre : Synthèse électrochimique et applications de films minces de composés HDL et rouilles vertes	Année : 2003
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible GFECI

Titre : formation du biofilm marin : conséquences et perspectives	Année : 2003
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible Séminaire VALOMER, pôle technologique de Bidart (Biarritz). 3-4 octobre 2003

Titre : Interactions entre la germination du dépôt calcomagnésien et la croissance de Desulfovibrio halophilus et Dethiosulfovibrio peptidovorans à la surface d’un acier carbone sous protection cathodique	Année : 2002
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible Colloque Matériaux 2002, Tours, 21-25 oct

Titre : Influence de la protection cathodique, d’acier immergé en milieu marin, sur la vitesse de colonisation de la flore sulfurogène	Année : 2002
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible 5ème forum de biodétérioration des matériaux (CEFRACOR/CNRS), Dourdan, 23-24 mai 2002

Titre : role of microorganisms on the formation of calcareous deposit resulted of cathodic protection applied in marine environment	Année : 2002
Auteur(s) : Pineau S. Lefèvre Y. Dupont-Morral I. Marsset B. Scherrer P. Auzeby C. Bénaïssa B. Abstract : Non disponible Forum CEFRACOR Cathodic protection and associated coatings, Aix en Provence