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Correia, Amabel Fernandes - One of the best experts on this subject based on the ideXlab platform.
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Isolamento, identificação e controle de microorganismos presentes em estruturas metálicas corroídas na usina hidroelétrica Coaracy Nunes
2013Co-Authors: Correia, Amabel FernandesAbstract:Corrosão é o processo espontâneo de deterioração, que ocorre em superfícies de materiais metálicos e não metálicos, por meio de reações químicas ou eletroquímicas, influenciada por vários fatores físicos, químicos e biológicos. Dentre os fatores biológicos, destacam-se os produtos do metabolismo microbiano e a formação de biofilme, capazes de modificar a interface substrato/solução, facilitando, iniciando, acelerando ou inibindo as reações de corrosão, sem alterar sua natureza eletroquímica. O processo corrosivo sob influência de microorganismos, denominado de biocorrosão, corrosão microbiológica ou corrosão influenciada microbiologicamente, representa grande problema mundial e acarreta elevadas perdas econômicas, além de danos ambientais. Na busca de alternativas para o controle e prevenção da corrosão influenciada microbiologicamente, este trabalho teve como principal objetivo detectar e caracterizar microorganismos, presentes nas estruturas metálicas corroídas e na água das tubulações da Usina Hidroelétrica Coaracy Nunes, localizada no estado do Amapá, bem como, testar 30 extratos brutos, obtidos de plantas medicinais coletadas na região amazônica do Amapá, quanto à ação antimicrobiana frente aos microorganismos isolados dos materiais coletados na usina. Para isto, técnicas microbiológicas, moleculares, de microscopia eletrônica e espectroscopia foram utilizadas. As técnicas microbiológicas de cultivo, de identificação bioquímica e da avaliação da atividade antimicrobiana, permitiram a caracterização de microorganismos das famílias Enterobacteriacea, Pseudomonadaceae, Bacillaceae, Corynebacteriaceae, Enterococcaceae, Dematiaceae e Moniliaceae e a demonstração da atividade antimicrobiana de 5 extratos frente a Pseudomonas aeruginosa e bactérias do gênero Bacillus. Na amplificação gênica pela reação em cadeia de polimerase (Polymerase Chain Reaction - PCR), foi detectado fragmento de 1300 pares de base correspondendo ao gene 16S rRNA, evidenciando a presença de microorganismos do domínio Arquea, e na análise por microscopia eletrônica de varredura e espectroscopia de energia dispersiva por raios – X, foi detectado a formação de biofilme e o potencial corrosivo das comunidades microbianas presentes no material coletado na usina. A importância destes achados, não só representam tentativas de controle da corrosão influenciada microbiologicamente in locu, como também promove o desenvolvimento sócio-econômico das populações circunvizinhas à usina, com relação a produção e comercialização de plantas medicinais como potenciais anticorrosivos/antimicrobianos. _______________________________________________________________________________________ ABSTRACTCorrosion is a spontaneous deterioration process that occurs over metallic and non-metallic material surfaces by chemical or electrochemical reactions, influenced by several physical, chemical and biological variables. Among the biological factors the products of microbial metabolism and biofilm formation are included which could modify the interface between substrate and solution, facilitating, initiating, accelerating or inhibiting the Corrosion reactions, without changing its electrochemical nature. The corrosive process under the influence of microorganisms, called bioCorrosion, Microbiological Corrosion or Microbiologically influenced Corrosion, represents an enormous global problem and causes huge economic losses and environmental damage. In search of alternative solutions for controlling and preventing the Microbiologically influenced Corrosion, this work aimed at detecting and characterizing microorganisms in corroded metal structures and water pipelines in the Coaracy Nunes Hydroelectric power plant, located in the state of Amapá, and, assaying 30 ethanolic crude extracts obtained from medicinal plants harvested in the Amazon region of Amapá, against microorganisms isolated from corroded materials collected at the power plant. In order to accomplish these objectives, Microbiological and molecular biology techniques, as also electron microscopy and spectroscopy analysis have been employed. Techniques of Microbiological cultivation, biochemical identification and evaluation of antimicrobial activity, allowed the characterization of microorganisms belonging to the Enterobacteriaceae, Pseudomonadaceae, Bacillaceae, Corynebacteriaceae, Enterococaceae, Dematiaceae and Moniliaceae families, besides the detection of antimicrobial activity exerted by 5 plant ethanolic crude extracts against Pseudomonas aeruginosa and the Bacillus genus. By genomic amplification utilizing the polymerase chain reaction, it was found a fragment of 1300 base pairs corresponding to the 16S rRNA gene, evidencing the presence of Archea domain microorganisms. Analysis by the scanning electron microscopy and the X ray energy dispersion techniques detected biofilm formation and the corrosive potential of microbial communities present in the material collected at the power plant. The importance of these findings not only represents attempts to control Microbiologically influenced Corrosion in locu, but also promote the socioeconomic development of the power plant surrounding populations regarding the production and marketing of medicinal plants as potential anticorrosive/antimicrobials
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Isolamento, identificação e controle de microorganismos presentes em estruturas metálicas corroídas na usina hidroelétrica Coaracy Nunes
2009Co-Authors: Correia, Amabel FernandesAbstract:Dissertação (Mestrado em Ciencias da Saúde)—Universidade de Brasília, Programa de Pós-graduação em Ciências da Saúde.Texto parcialmente liberado pelo autor. Conteúdo disponível: Resumo.Corrosão é o processo espontâneo de deterioração, que ocorre em superfícies de materiais metálicos e não metálicos, por meio de reações químicas ou eletroquímicas, influenciada por vários fatores físicos, químicos e biológicos. Dentre os fatores biológicos, destacam-se os produtos do metabolismo microbiano e a formação de biofilme, capazes de modificar a interface substrato/solução, facilitando, iniciando, acelerando ou inibindo as reações de corrosão, sem alterar sua natureza eletroquímica. O processo corrosivo sob influência de microorganismos, denominado de biocorrosão, corrosão microbiológica ou corrosão influenciada microbiologicamente, representa grande problema mundial e acarreta elevadas perdas econômicas, além de danos ambientais. Na busca de alternativas para o controle e prevenção da corrosão influenciada microbiologicamente, este trabalho teve como principal objetivo detectar e caracterizar microorganismos, presentes nas estruturas metálicas corroídas e na água das tubulações da Usina Hidroelétrica Coaracy Nunes, localizada no estado do Amapá, bem como, testar 30 extratos brutos, obtidos de plantas medicinais coletadas na região amazônica do Amapá, quanto à ação antimicrobiana frente aos microorganismos isolados dos materiais coletados na usina. Para isto, técnicas microbiológicas, moleculares, de microscopia eletrônica e espectroscopia foram utilizadas. As técnicas microbiológicas de cultivo, de identificação bioquímica e da avaliação da atividade antimicrobiana, permitiram a caracterização de microorganismos das famílias Enterobacteriacea, Pseudomonadaceae, Bacillaceae, Corynebacteriaceae, Enterococcaceae, Dematiaceae e Moniliaceae e a demonstração da atividade antimicrobiana de 5 extratos frente a Pseudomonas aeruginosa e bactérias do gênero Bacillus. Na amplificação gênica pela reação em cadeia de polimerase (Polymerase Chain Reaction - PCR), foi detectado fragmento de 1300 pares de base correspondendo ao gene 16S rRNA, evidenciando a presença de microorganismos do domínio Arquea, e na análise por microscopia eletrônica de varredura e espectroscopia de energia dispersiva por raios – X, foi detectado a formação de biofilme e o potencial corrosivo das comunidades microbianas presentes no material coletado na usina. A importância destes achados, não só representam tentativas de controle da corrosão influenciada microbiologicamente in locu, como também promove o desenvolvimento sócio-econômico das populações circunvizinhas à usina, com relação a produção e comercialização de plantas medicinais como potenciais anticorrosivos/antimicrobianos. _______________________________________________________________________________________ ABSTRACTCorrosion is a spontaneous deterioration process that occurs over metallic and non-metallic material surfaces by chemical or electrochemical reactions, influenced by several physical, chemical and biological variables. Among the biological factors the products of microbial metabolism and biofilm formation are included which could modify the interface between substrate and solution, facilitating, initiating, accelerating or inhibiting the Corrosion reactions, without changing its electrochemical nature. The corrosive process under the influence of microorganisms, called bioCorrosion, Microbiological Corrosion or Microbiologically influenced Corrosion, represents an enormous global problem and causes huge economic losses and environmental damage. In search of alternative solutions for controlling and preventing the Microbiologically influenced Corrosion, this work aimed at detecting and characterizing microorganisms in corroded metal structures and water pipelines in the Coaracy Nunes Hydroelectric power plant, located in the state of Amapá, and, assaying 30 ethanolic crude extracts obtained from medicinal plants harvested in the Amazon region of Amapá, against microorganisms isolated from corroded materials collected at the power plant. In order to accomplish these objectives, Microbiological and molecular biology techniques, as also electron microscopy and spectroscopy analysis have been employed. Techniques of Microbiological cultivation, biochemical identification and evaluation of antimicrobial activity, allowed the characterization of microorganisms belonging to the Enterobacteriaceae, Pseudomonadaceae, Bacillaceae, Corynebacteriaceae, Enterococaceae, Dematiaceae and Moniliaceae families, besides the detection of antimicrobial activity exerted by 5 plant ethanolic crude extracts against Pseudomonas aeruginosa and the Bacillus genus. By genomic amplification utilizing the polymerase chain reaction, it was found a fragment of 1300 base pairs corresponding to the 16S rRNA gene, evidencing the presence of Archea domain microorganisms. Analysis by the scanning electron microscopy and the X ray energy dispersion techniques detected biofilm formation and the corrosive potential of microbial communities present in the material collected at the power plant. The importance of these findings not only represents attempts to control Microbiologically influenced Corrosion in locu, but also promote the socioeconomic development of the power plant surrounding populations regarding the production and marketing of medicinal plants as potential anticorrosive/antimicrobials
Dun Zhang - One of the best experts on this subject based on the ideXlab platform.
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sulfide ions induced release of biocides from a metal phenolic supramolecular film fabricated on aluminum for inhibition of microbially influenced Corrosion
Corrosion Science, 2020Co-Authors: Haoyuan Cai, Peng Wang, Xiaotong Chen, Yu Wang, Dun ZhangAbstract:Abstract Herein, we fabricate a novel metal-phenolic supramolecular film on aluminium, which can control release of loaded biocides when S2− concentration is higher than 10 mM or in sulfate reducing bacteria (SRB) environment with a long incubation period. The protection effect of the film on microbially influenced Corrosion (MIC) induced by SRB is analyzed with fluorescence microscopy and electrochemical measurement. A novel Microbiological Corrosion protection mechanism is proposed based on its effective roles to suppress SRB settlement and insulate corrosive medium. The intelligent film maintains a longtime antibacterial behavior owing to its S2--responsive character, which enhances the Microbiological Corrosion resistance.
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Slippery liquid-infused porous surfaces fabricated on aluminum as a barrier to Corrosion induced by sulfate reducing bacteria
Corrosion Science, 2015Co-Authors: Peng Wang, Zhou Lu, Dun ZhangAbstract:Abstract Microbiological Corrosion induced by sulfate reducing bacteria (SRB) is one of the main threatens to the safety of marine structure. To reduce Microbiological Corrosion, slippery liquid infused porous surfaces (SLIPS) were designed and fabricated on aluminum substrate by constructing rough aluminum oxide layer, followed by fluorination of the rough layer and infiltration with lubricant. The as-fabricated SLIPS were characterized with wettability measurement, SEM and XPS. Their resistances to Microbiological Corrosion induced by SRB were evaluated with fluorescence microscopy and electrochemical measurement. It was demonstrated that they present high resistance to bacteria adherence and the resultant Microbiological Corrosion in static seawater.
E Ramous - One of the best experts on this subject based on the ideXlab platform.
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a study of the Microbiological Corrosion products of steel and cast iron pipes in fresh water
Journal of Materials Science, 1991Co-Authors: B Badan, M Magrini, E RamousAbstract:Biological Corrosion is one of the most common corrosive processes found in steel, cast iron and other metals placed in soil, sea water and fresh water. We have studied this type of Corrosion development process in steel and cast iron pipes. This Corrosion process shows tubercular morphology on the inside surface of pipes. Resulting Corrosion products have been examined by: chemical analysis, scanning electron microscopy (SEM), X-ray diffraction (XRD) and Mossbauer spectroscopy. In all the samples the following iron compounds were found: α-FeOOH (Goethite), γ-FeOOH (Lepidocrocite), non-stoichiometric Fe3O4 and colloidal hydrate oxide Fe(OH)3 · 0.9H2O. Small quantities of α-FeOOH and γ-FeOOH compounds were present as small size grain particles (10–20 nm). These particles may be considered responsible for worsening the organoleptic properties of water.
Marcus Ferreira - One of the best experts on this subject based on the ideXlab platform.
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expanding the durability of stainless steels in water systems under Microbiological Corrosion conditions
Europace, 2007Co-Authors: N De Cristofaro, E Menaaroni, J Telegdi, N Arlt, P Gumpel, D Schiller, Matress V Serrano, Moura T E Silva, Marcus FerreiraAbstract:Microbiological Corrosion (MIC) of steel structures of waters treatments plants is a serious material durability problem, which occurs in the presence of microbes, adequate nutrients and corrosive products, leading to changes in the rate and sometimes aiso the type of the electrochemical Corrosion reactions. Different aspects on MIC of stainless steels in water treatment plants were studied, but intensive work on these problems is still missing. This European project, intends to asses the performance of typical stainless steels and newer stainless steels grades with enhanced Corrosion resistance and to define suitable tools to prevent MIC failure including recommendations and procedures for usage of these materials. The examined corc materials were the following austenitic stainless steels: EN 1.4301, the EN 1.4401 and the modified EN 1.4301. The improved Corrosion resistant stainless steel grades included in the project were the following: EN 1.4462, EN 1.4539 und EN 1.4565.
B Badan - One of the best experts on this subject based on the ideXlab platform.
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a study of the Microbiological Corrosion products of steel and cast iron pipes in fresh water
Journal of Materials Science, 1991Co-Authors: B Badan, M Magrini, E RamousAbstract:Biological Corrosion is one of the most common corrosive processes found in steel, cast iron and other metals placed in soil, sea water and fresh water. We have studied this type of Corrosion development process in steel and cast iron pipes. This Corrosion process shows tubercular morphology on the inside surface of pipes. Resulting Corrosion products have been examined by: chemical analysis, scanning electron microscopy (SEM), X-ray diffraction (XRD) and Mossbauer spectroscopy. In all the samples the following iron compounds were found: α-FeOOH (Goethite), γ-FeOOH (Lepidocrocite), non-stoichiometric Fe3O4 and colloidal hydrate oxide Fe(OH)3 · 0.9H2O. Small quantities of α-FeOOH and γ-FeOOH compounds were present as small size grain particles (10–20 nm). These particles may be considered responsible for worsening the organoleptic properties of water.