40 resultados para Deterioração microbiana

em Universidade Federal do Rio Grande do Norte(UFRN)


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The biodiesel use has become important due to its renewable character and to reduce environmental impacts during the fuel burning. Theses benefit will be valid if the fuel shows good performance, chemistry stability and compatibility with engines. Biodiesel is a good fuel to diesel engines due to its lubricity. Then, the aimed of this study was to verify the physicalchemistry properties of biodiesel and their correlations with possible elastomers damage after biodiesel be used as fuel in an injection system. The methodology was divided in three steps: biodiesels synthesis by transesterification of three vegetable oil (soybean, palm and sunflower) and their physical-chemistry characterization (viscosity, oxidative stability, flash point, acidity, humidity and density); pressurized test of compatibility between elastomers (NBR and VITON) and biodiesel, and the last one, analyze of biodiesels lubricity by tribological test ball-plan( HFRR). Also, the effect of mixture of biodiesel and diesel in different concentrations was evaluated. The results showed that VITON showed better compatibility with all biodiesel blends in relation to NBR, however when VITON had contact with sunflower biodiesel and its blends the swelling degree suffer higher influences due to biodiesel humidity. For others biodiesels and theirs blends, this elastomer kept its mechanical properties constant. The better tribological performance was observed for blends with high biodiesel concentration, lower friction coefficient was obtained when palm biodiesel was used. The main mechanisms observed during the HFRR tests were abrasive and oxidative wear

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In the contemporary world to the deterioration of semi-arid areas of the planet has been the focus of media attention and the scientific community. Brazil has a semiarid, considered the most problematic of the world, either by pressure from physical factors, whether as a result of misguided public policies, has over time been suffering from the consequences of a deterioration that expands over the years. Methodologies, that amidst the problems of semi-arid, come against the deteriorating local, have a good chance to be reapplied in other contexts around the world. This research, based on methodological model for analyzing environmental deterioration, introduced and examined the applicability of the methodology in the semi-arid region of Rio Grande do Norte - Brazil. Although the results provide guidelines for the introduction of underground dams, the application of the methodology was ineffective, given the high rates of forest cover that gave low values for the physical diagnosis conservationist

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The screening for genes in metagenomic libraries from soil creates opportunities to explore the enormous genetic and metabolic diversity of microorganisms. Rivers are ecosystems with high biological diversity, but few were examined using the metagenomic approach. With this objective, a metagenomic library was constructed from DNA soil samples collected at three different points along the Jundiaí-river (Rio Grande do Norte-Brazil). The points sampled are from open area, rough terrain and with the direct incidence of sunlight. This library was analyzed functionally and based in sequence. For functional analysis Luria-Bertani solid medium (LB) with NaCl concentration varied from 0.17M to 0.85M was used for functional analysis. Positives clones resistant to hypersaline medium were obtained. The recombinant DNAs were extracted and transformed into Escherichia coli strain DH10B and survival curves were obtained for quantification of abiotic stress resistance. The sequences of clones were obtained and submitted to the BLASTX tool. Some clones were found to hypothetical proteins of microorganisms from both Archaea and Bacteria division. One of the clones showed a complete ORF with high similarity to glucose-6-phosphate isomerase which participates in the synthesis of glycerol pathway and serves as a compatible solute to balance the osmotic pressure inside and outside of cells. Subsequently, in order to identify genes encoding osmolytes or enzymes related halotolerance, environmental DNA samples from the river soil, from the water column of the estuary and ocean were collected and pyrosequenced. Sequences of osmolytes and enzymes of different microorganisms were obtained from the UniProt and used as RefSeqs for homology identification (TBLASTN) in metagenomic databases. The sequences were submitted to HMMER for the functional domains identification. Some enzymes were identified: alpha-trehalose-phosphate synthase, L-ectoina synthase (EctC), transaminase L-2 ,4-diaminobutyric acid (EctB), L-2 ,4-diaminobutyric acetyltransferase (EctA), L-threonine 3 dehydrogenase (sorbitol pathway), glycerol-3-phosphate dehydrogenase, inositol 3-phosphate dehydrogenase, chaperones, L-proline, glycine betaine binding ABC transporter, myo-inositol-1-phosphate synthase protein of proline simportadora / PutP sodium-and trehalose-6-phosphate phosphatase These proteins are commonly related to saline environments, however the identification of them in river environment is justified by the high salt concentration in the soil during prolonged dry seasons this river. Regarding the richness of the microbiota the river substrate has an abundance of halobacteria similar to the sea and more than the estuary. These data confirm the existence of a specialized response against salt stress by microorganisms in the environment of the Jundiaí river

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Metal-Ceramic (M/C) Zirconia-stainless steel interfaces have been processed through brazing techniques due to the excellent combination of properties such as high temperature stability, high corrosion resistance and good mechanical properties. However, some M/C interfaces show some defects, like porosity and cracks results in the degradation of the interfaces, leading even to its total rupture. Most of time, those defects are associated with an improper brazing parameters selection to the M/C system. In this work, ZrO2 Y-TZP and ZrO2 Mg - PSZ were joint with the stainless steel grade 304 by brazing using a eutectic silver-copper (Ag28Cu) interlayer alloy with different thermal cycles. Ceramic surfaces were previous mechanically metallized with titanium to improve adhesion of the system. The effect of temperature on the M/C interface was studied. SEM-EDS and 3 point flexural bend test were performed to evaluate morphology, chemical composition and mechanical resistance of the M/C interfaces. Lower thermal cycle temperatures produced better results of mechanical resistance, and more regular/ homogeneous reaction layers between braze alloy and metal-ceramic surfaces. Also was proved the AgCu braze alloy activation in situ by titanium

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The biofilms microbial forms of association are responsible for generating, accelerating and / or induce the process of corrosion. The damage generated in the petroleum industry for this type of corrosion is significatives, representing major investment for your control. The aim of this study was to evaluate such tests antibiograms the effects of extracts of Jatropha curcas and essential oil of Lippia gracilis Schauer on microrganisms isolated from water samples and, thereafter, select the most effective natural product for further evaluation of biofilms formed in dynamic system. Extracts of J. curcas were not efficient on the complete inhibition of microbial growth in tests type antibiogram, and essential oil of L. gracilis Schauer most effective and determined for the other tests. A standard concentration of essential oil of 20 μL was chosen and established for the evaluation of the biofilms and the rate of corrosion. The biocide effect was determined by microbial counts of five types of microorganisms: aerobic bacteria, precipitating iron, total anaerobic, sulphate reducers (BRS) and fungi. The rate of corrosion was measured by loss of mass. Molecular identification and scanning electron microscopy (SEM) were performed. The data showed reduction to zero of the most probable number (MPN) of bacteria precipitating iron and BRS from 115 and 113 minutes of contact, respectively. There was also inhibited in fungi, reducing to zero the rate of colony-forming units (CFU) from 74 minutes of exposure. However, for aerobic and anaerobic bacteria there was no significant difference in the time of exposure to the essential oil, remaining constant. The rate of corrosion was also influenced by the presence of oil. The essential oil of L. gracilis was shown to be potentially effective

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The transport of fluids through pipes is used in the oil industry, being the pipelines an important link in the logistics flow of fluids. However, the pipelines suffer deterioration in their walls caused by several factors which may cause loss of fluids to the environment, justifying the investment in techniques and methods of leak detection to minimize fluid loss and environmental damage. This work presents the development of a supervisory module in order to inform to the operator the leakage in the pipeline monitored in the shortest time possible, in order that the operator log procedure that entails the end of the leak. This module is a component of a system designed to detect leaks in oil pipelines using sonic technology, wavelets and neural networks. The plant used in the development and testing of the module presented here was the system of tanks of LAMP, and its LAN, as monitoring network. The proposal consists of, basically, two stages. Initially, assess the performance of the communication infrastructure of the supervisory module. Later, simulate leaks so that the DSP sends information to the supervisory performs the calculation of the location of leaks and indicate to which sensor the leak is closer, and using the system of tanks of LAMP, capture the pressure in the pipeline monitored by piezoresistive sensors, this information being processed by the DSP and sent to the supervisory to be presented to the user in real time

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Knowledge of the native prokaryotes in hazardous locations favors the application of biotechnology for bioremediation. Independent strategies for cultivation and metagenomics contribute to further microbiological knowledge, enabling studies with non-cultivable about the "native microbiological status and its potential role in bioremediation, for example, of polycyclic aromatic hydrocarbons (HPA's). Considering the biome mangrove interface fragile and critical bordering the ocean, this study characterizes the native microbiota mangrove potential biodegradability of HPA's using a biomarker for molecular detection and assessment of bacterial diversity by PCR in areas under the influence of oil companies in the Basin Petroleum Geology Potiguar (BPP). We chose PcaF, a metabolic enzyme, to be the molecular biomarker in a PCR-DGGE detection of prokaryotes that degrade HPA s. The PCR-DGGE fingerprints obtained from Paracuru-CE, Fortim-CE and Areia Branca-RN samples revealed the occurrence of fluctuations of microbial communities according to the sampling periods and in response to the impact of oil. In the analysis of microbial communities interference of the oil industry, in Areia Branca-RN and Paracuru-CE was observed that oil is a determinant of microbial diversity. Fortim-CE probably has no direct influence with the oil activity. In order to obtain data for better understanding the transport and biodegradation of HPA's, there were conducted in silico studies with modeling and simulation from obtaining 3-D models of proteins involved in the degradation of phenanthrene in the transport of HPA's and also getting the 3-D model of the enzyme PcaF used as molecular marker in this study. Were realized docking studies with substrates and products to a better understanding about the transport mechanism and catalysis of HPA s

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Industrial activities, oil spills and its derivatives, as well as the incomplete combustion of fossil fuels have caused a great accumulation of hydrocarbons in the environment. The number of microorganisms on the planet is estimated at 1030 and prokaryotes the most abundant. They colonized diverse environments for thousands of years, including those considered extreme and represent an untapped source of metabolic and genetic diversity with a large biotechnological potential. It is also known that certain microorganisms have the enzymatic capacity to degrade petroleum hydrocarbons and, in many ecosystems, there is an indigenous community capable of performing this function. The metagenomic has revolutionized the microbiology allowing access uncultured microbial communities, being a powerful tool for elucidation of their ecological functions and metabolic profiles, as well as for identification of new biomolecules. Thus, this study applied metagenomic approaches not only for functional selection of genes involved in biodegradation and emulsification processes of the petroleum-derived hydrocarbons, but also to describe the taxonomic and metabolic composition of two metagenomes from aquatic microbiome. We analyzed 123.116 (365 ± 118 bp) and 127.563 sequences (352 ± 120 bp) of marine and estuarine metagenomes, respectively. Eight clones were found, four involved in the petroleum biodegradation and four were able to emulsify kerosene indicating their abilities in biosurfactants synthesis. Therefore, the metagenomic analyses performed were efficient not only in the search of bioproducts of biotechnological interest and in the analysis of the functional and taxonomic profile of the metagenomes studied as well

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This anthropological study investigates the lived-experience of oral diseases in the context of poverty in Northeast Brazil. During six months in 2004???, ethnographic interviews, narratives and participant-observation with 31 residents of the low-income community, Dendê, located in Fortaleza, Ceará were conducted and analyzed utilizing a hermeneutic-dialetic method. It is revealed that precarious life conditions make prioritizing caretaking a difficult task. Despite suffering tooth pain, seeking a dentist's care is perceived as "a luxury" not a citzens' right. Difficulties in accessing services and poor quality restorations, favor tooth extractions as the most effective intervention. The deterioration of one's oral health is lamented by community members who seek help from popular clinics, politicians and traditional healers. The experience of dental disease differs according to social class, leaves oral scars of inequity, harms self-esteem and inhibits social inclusion. In this context, "treating" the Teeth of Inequity demands that we deepen our comprehension of the social determinants of health, reduce injustice in the access to quality care, remove demoralizing stigmas and empower the community to confront structural forces which affect its life

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O presente estudo objetivou analisar as características epidemiológicas das condições de saúde bucal de 98 idosos de uma Instituição de Longa Permanência para Idosos (ILPI) e de 125 participantes de Grupos de Convivência, de bairros periféricos, socialmente semelhantes, de Fortaleza, Ceará, Brasil, para orientação do tratamento odontológico. Investigou-se a autopercepção em saúde bucal desses idosos a fim de realizar uma avaliação comparativa entre eles e com os levantamentos epidemiológicos de base nacional (SB Brasil) e de base estadual (SB Ceará). Devido a alguns idosos da ILPI recusarem o tratamento dentário e a identificação do elevado percentual de demenciados, optou-se por realizar uma avaliação cognitiva, o Mini Exame do Estado Mental (MEEM) visando identificar os aptos à reabilitação oral. Métodos: abordagem epidemiológica do tipo transversal, sendo a coleta de dados realizada por cinco examinadores, utilizando os critérios recomendados pela OMS (1997). Resultados: O CPO-D médio encontrado na ILPI, foi de 29,88, com predomínio do componente perdido (93,27%) enquanto o CPO-D médio dos não institucionalizados fixou-se em 30,17, com predomínio do componente perdido (63,70%). Também se avaliou o uso e a necessidade de prótese dentária: dos residentes na ILPI, 10,20% usavam prótese superior e 3,06%, inferior; 94,90% necessitavam de prótese superior e 97,96% de inferior; sendo a prótese total foi o tipo mais prevalente, 88,78% para ambos os arcos. O percentual do uso de prótese dos não institucionalizados foi 71,20% no arco superior, sendo 66,40% prótese total; já para o arco inferior, 32,80%, das quais 31,20% era prótese total. No presente estudo, tanto para uso quanto para necessidade, considerando ambos os arcos, a diferença entre os idosos institucionalizados e não institucionalizados foi estatisticamente significativa pelo teste Qui - quadrado (p<0,001). Como resultado do MEEM, observou-se deterioração cognitiva (escore ≤ 12) em 37,25% dos entrevistados, bem como um declínio cognitivo com o avanço da idade. Conclusões: Os resultados apontam que há um maior percentual de uso de prótese total no arco superior e maior frequência quanto à ausência de próteses de qualquer tipo no arco inferior. Evidenciou-se que os idosos pesquisados foram submetidos a tratamento mutilador e, como consequência necessitam de reabilitação oral, o que pressupõe a necessidade de políticas públicas para que isso ocorra efetivamente. Os participantes deste estudo caracterizam-se por uma autopercepção positiva da sua saúde bucal, a despeito das condições clínicas insatisfatórias e de precária saúde bucal, com acentuada prevalência de cárie dentária e edentulismo. O MEEM revelou deficiência cognitiva na maioria dos idosos, confirmando que a sua aplicação, previamente à reabilitação oral pode evitar desperdícios financeiros.Tais achados refletem a necessidade de implantação de políticas reabilitadoras em saúde bucal voltadas para o idoso; baseadas na perspectiva da integralidade como princípio doutrinário do Sistema Único de Saúde, o que redundaria numa melhor qualidade de vida, tanto pela melhor mastigação, digestão e nutrição, pelo maior aproveitamento dos alimentos, quanto pelo favorecimento à comunicação, pela dicção e fala, contribuindo para a socialização e consequente elevação da autoestima dessa clientela.

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A resistência microbiana a antimicrobianos tem favorecido a busca por substâncias bioativas provenientes de plantas usadas na medicina popular, com o intuito de se obter novos fármacos com atividade antimicrobiana. Neste estudo, foi proposta a investigação da atividade antibacteriana do óleo-resina de Copaifera duckei e de diferentes extratos da casca de Pseudobombax marginatum, e seus possíveis mecanismos de ação. O potencial inibitório antibacteriano foi avaliado utilizando-se os métodos de difusão e diluição em ágar, e a bioautografia. O mecanismo de ação foi analisado por microscopia eletrônica, no qual se observou alterações na ultraestrutura bacteriana, e por eletroforese em SDS-PAGE, que determinou ação sobre as proteínas das superfícies celulares. A análise química foi realizada pelas técnicas de Espectrometria de massas acoplada ao Cromatógrafo a gás- EM/CG (C. duckei) e Cromatografia Líquida de Alta Eficiência- CLAE (P. marginatum). Entre as bactérias estudadas, B. cereus foi a mais suscetível às plantas em estudo, com concentrações inibitórias mínimas (CIMs) correspondentes a 0,3125 mg/mL para o óleo-resina de copaíba, e 0,5 mg/mL para extrato hidroalcoólico (1:1) e 0,512 mg/mL para a fração butanólica da casca P. marginatum, nos quais pôde-se observar alterações na parede celular do B. cereus, com remoção da camada S, espessamento da parede celular e formação de diversos septos nos centros de divisão celular. A análise química por EM/CG mostrou compostos terpênicos no óleo-resina de C. duckei, tendo como composto majoritário o β-bisaboleno, e a análise por CLAE mostrou a presença de compostos derivados da catequina na casca do P. marginatum. Desta forma, as plantas em estudo mostram um potencial antibacteriano considerável, podendo contribuir tanto na terapia antimicrobiana como na área de alimentos, tendo como um de seus prováveis sítios de ação a parede celular bacteriana

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Schinus terebinthifolius Raddi is used in the treatment of skin and mucosal injuries, infections of respiratory, digestive and genitourinary systems. Currently one of the biggest problems faced for the industry of phytopharmaceuticals with regard to the quality of raw materials is the microbial contamination. The aim this study was to evaluate the antimicrobial action of the hidroalcoholic extract of aroeira, beyond testing the effectiveness of the preservative system in hidrogel to the base of this extract. The extracts were prepared by maceration in the ratio of 1:10 of solvent plant/with alcohol 40%. The methods for microbial count were pour plate and test for specific microorganisms, analyzing in third copy each one of the samples. The antimicrobial activity of aroeira extracts was performed using an agar diffusion method, using strains of S. aureus, P. aeruginosa, E. coli, B. subtilis, C. albicans, C. tropicalis, C. krusei, C. guilliermondii, T. rubrum, M. gypseum, A. flavus and A. niger. The formula with aroeira was evaluated by the challenge test. This method consisted of artificial contamination the sample with separate inóculos of A. niger, C. albicans, E. coli e S. aureus aeruginosa and determinations of survivors for the method of counting for pour plate , during times 0, 24h, 48h, 7 days, 14 days, 21 days and 28 days. How much to the results, one verified that the extract of aroeira in the 13,5 concentration mg/mL presented antimicrobial activity for cepas of E. coli, B. subtilis, P. aeruginosa e S. aureus, producing inhibition zone, on average with 13 mm of diameter. However it did not present no fungi activity. The formula with aroeira containig both methylparaben and propylparaben showed a good efficacy in challenge test front to strains of A. niger, C. albicans, E. coli, S. aureus. The A criteria of European Pharmacopoeia, adopted in this work, was verified that this product revealed the good preservative efficacy for the challenge test, time interval of the 28 days. However, it is interesting to extend this study, in order to carry through the sped up stability and the test of shelf, to establish the validity of this formularization

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The apparent virtuosity that if could wait of the globalization and the neoliberalism has given signals of deterioration in the contractual relations, especially in contracts of mass consumption, generating innumerable offensive situations to the basic rights and the goods constitutionally protected of the contractors. In the world of today, still that it does not reveal any desire, the individual practically is compelled to contract, for force of necessities and customs completely imposed, mainly in face of the essentiality of the services or agreed to goods. Ahead of as much and unexpected changes in the civil liames and of consumption, dictated for the globalization, it comes to surface the reflection if the private law e, more specifically, the civil law, meet prepared adequately to deal with these new parameters of the economy. The present dissertation has the intention to investigate if the globalization and the consequent neoliberalism, in this beginning of third millennium, will imply to revive of the principles and the basics paradigms of the contracts that consolidated and had kept, for more than two centuries, the liberal State. One notices that the study of this phenomenon it gains importance to the measure where if it aggravates the decline of the social State (Welfare State), with the embrittlement and the loss of the autonomy of the state authority, over all in countries of delayed modernity, as it is the case of Brazil, that presents deep deficiencies to give or to promote, with a minimum of quality and efficiency, essential considered public services to the collective and that if they find consecrated in the Federal Constitution, as basic rights or as goods constitutionally protecting, the example of the health, the education, the housing, the security, the providence, the insurance, the protection the maternity, the infancy and of aged and deficient. To the end, the incidence of constant basic rights of the man in the Constitution is concluded that, in the process of interpretation of the right contractual conflicts that have as object rights or goods constitutionally proteges, in the universe of the globalized perhaps economy and of the neoliberalismo, it consists in one of the few ways - unless the only one - that still they remain to over all deal with more adequately the contractual relations, exactly that if considers the presence of clauses generalities in the scope of the legislation infraconstitutional civil and of consumption, front the private detainers of social-economic power. To be able that it matters necessarily in disequilibrium between the parts, whose realignment depends on the effect and the graduation that if it intends to confer to the basic right in game in the private relation. The Constitution, when allowing the entailing of the basic rights in the privates relations, would be assuming contours of a statute basic of all the collective, giving protection to the man against the power, if public or independently private

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Protozoa may be an important alternative food source for Calanoida copepods in these environments. Aiming to quantify the feeding preferences of N. cearensis by ciliates in the presence of cyanobacteria, in vitro experiments were conducted, using mixed cultures in different concentrations of total food for copepod. Two ciliates species (Paramecium sp. and Cyclidium sp.) and a cyanobacteria toxic strain (Microcystis aeruginosa) were offered as food. Previous experiments were done to identify the copepod s maximum ingestion rate through the use of a type II functional response model when each prey is offered separately. High maximum ingestion rate were found when those protists were offered as prey. N. cearensis showed significant preference for protozoal prey over the cyanobacterium tested both in low (corresponding 95.15% of the diet) and in high food concentration treatments (about 91.56% of the diet), preferring the bigger ciliate in lower concentrations (67.52% of the diet). The meaningful involvement of heterotrophic organisms in the zooplankton diet emphasis the microbial loop participation in the energy transition from copepods to higher trophic levels. This data contributes to understand the stability of existing trophic interactions in reservoirs subjected to eutrophication and assists trophic cascade studies in these environments

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Infrastructure works are included in strategic areas for the social development. For that matter that all of the investments are very important for the social development. When the population has enough water and an acceptable quality, and it includes a wastewater gathering and its treatment, the whole society became less susceptible to the water diseases. Even the Water Supply and the Sewage depend for its perfect operation of reservoirs, or of the accumulation of water to provide the popular necessity, either due to retention or for the treatment wastewarer. These structures present very specific environmental conditions, because the microclimate created around them, like high environmental humidity and for the existence of many harmful substances for the concrete, such as chloride ions presents in water. The reservoir that compose the System of Water Supply of Natal were built between 1970s and 1980s, a period whom the technical and scientific community did not have in-depth studies about the reinforced concrete mechanism of deterioration. Therefore, these reservoirs have been suffered accelerated deterioration progress, and they have been shown many pathological manifestations strikingly visible. In front of all these problems this academic work aims to identify the generally conditions of conservation of all the reservoirs components of the Water Supply System of Natal. This academic work objectives to develop a recuperation plan for use in these reservoirs, in this academic work it was achieved all the survey of pathological manifestation existing in each reservoir. It was made with local visits, photographic recorders of all manifestations viii and realization of in loco tests. The other step consisted in a application of GDE/UnB metodolgy reformulated by Fonseca (2007). In the step of local visits in each reservoir it was evaluated carbonation depth, by spreading a phenolphthalein solution with 1% of concentration; evaluation of contamination of chlorides, by spreading silver nitrate solution with 1% of concentration, and evaluation of width cracks. After the conclusion of all the testings, it was established that all reservoir, studied in this academic work, have showed an advanced deteriorating condition. It´s presents prevalent pathological manifestations as unacceptable cracks, spots, efflorescence and reinforcement corrosion, and in some cases, chlorides contamination. After the conclusion of the testings and its concatenation it was able to implementing, using GDE/UnB methodology, the order of the restoration its service life and initial safety conditions