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Registros recuperados: 39 | |
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Cordier, Clémence; Stavrakakis, Christophe; Morga, Benjamin; Degrémont, Lionel; Voulgaris, Alexandra; Bacchi, Alessia; Sauvade, Patrick; Coelho, Franz; Moulin, Philippe. |
Among water treatment processes, ultrafiltration is known to be efficient for the elimination of micro-organisms (bacteria and viruses). In this study, two pathogens were targeted, a bacterium, Vibrio aestuarianus and a virus, OsHV-1, with the objective to produce high quality water from seawater, in the case of shellfish productions. The retention of those microorganisms by ultrafiltration was evaluated at labscale. In the case of OsHV-1, the protection of oysters was validated by in vivo experiments using oysters spat and larvae, both stages being highly susceptible to the virus. The oysters raised using contaminated seawater which was then subsequently treated by ultrafiltration, had similar mortality to the negative controls. In the case of V.... |
Tipo: Text |
Palavras-chave: Ultrafiltration; Biosecurisation; Pathogen retention; Sea water; OsHV-1; Shellfish production. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00634/74576/74466.pdf |
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Le Gac, Pierre-yves; Choqueuse, Dominique; Melot, D.. |
Polymers are widely used for passive thermal insulation coatings on steel pipe in offshore oil and gas production. In this industry, structures used in deep sea have to be reliable, as they are in service for more than 20 years in a very severe environment: sea water, hydrostatic pressure and temperature gradient. One of the main questions is how to test and predict the lifetime of such structures in the laboratory? This study presents one approach that has been developed to characterize and predict the degradation of polymers used as thermal insulation materials. This paper is dedicated to polyurethane (polyether based) degradation in sea water at high temperature. Ageing has been performed in natural sea water under hydrostatic pressure at temperatures... |
Tipo: Text |
Palavras-chave: Polyurethane; Hydrolysis; Accelerated ageing; Sea water; Coating; Offshore. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00160/27132/25330.pdf |
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Le Gac, Pierre-yves; Le Saux, V.; Paris, M; Marco, Y.. |
Polymers are widely used in marine environments due to their excellent properties and good weathering resistance. Despite this extensive use, their long term behaviour in such an aggressive environment is still not well known. To assess the polymer durability within reasonable durations, it is essential to perform accelerated ageing tests to accelerate the degradation kinetics but without any modification of the degradation process. This study therefore proposes and validates accelerated ageing tests to study marine ageing of a silica-filled chloroprene rubber (CR) used for offshore applications. Several accelerated ageing protocols are investigated for temperatures ranging from 20 to 80 degrees C in renewed natural seawater. The ageing consequences are... |
Tipo: Text |
Palavras-chave: Chloroprene rubber; Degradation; Sea water; Silica; Accelerated ageing; Natural ageing. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00073/18429/20232.pdf |
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Labasque, Thierry; Chaumery, Christian; Aminot, Alain; Kergoat, Gilles. |
The spectrophotometric iodine measurement for oxygen determination by the Winkler method is re-examined for theoretical and operational aspects. It is shown that the selection of an isobestic point for measuring the mixture of iodine and tri-iodide in the solution enhances reliability. The wavelength value of 466 nm was selected after a spectrum study. Then, performances are assessed by mean of statistical approach based on repeated standardization curves at the isobestic point compared with other wavelengths. At 466 nm, the method is linear up to about 1000 mumol kg(-1) of O-2. Optimization and validation of the spectrophotometric method is realized through a robustness study based on factors that may alter the results (temperature, reagent volumes,... |
Tipo: Text |
Palavras-chave: Isobestic point; Sea water; Spectrophotometry; Dissolved oxygen. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/publication-1694.pdf |
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Blanke, Bruno; Arhan, Michel; Lazar, A; Prevost, Gwenaelle. |
The origins and fates of the Atlantic salinity maximum water (SMW), formed through excess evaporation in the tropics and subtropics of both hemispheres, are studied using monthly mean outputs of a numerical simulation of the world ocean climatological circulation. After defining formation domains from the surface salinity field and the vertical stratification, a Lagrangian technique is used to estimate the formation rates and main pathways in each hemisphere and the role of this water in the framework of the warm water return flow of the meridional overturning cell. Formation rates around 9 and 11 Sv are found in the Southern and Northern Hemispheres, respectively. While the export of the southern SMW from its formation area is realized by the western... |
Tipo: Text |
Palavras-chave: Atlantic ocean; Lagrangian method; Numerical simulation; Salinity; Sea water. |
Ano: 2002 |
URL: https://archimer.ifremer.fr/doc/2002/publication-769.pdf |
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Bruni, V; Crisafi, E; Maugeri, T; Zaccone, R. |
110 Vibrio strains were isolated, at various times of the year, from samples of sea-water supply, breeding-tank water and discarded fish used as food at the breeding stations. From the results obtained by the biochemical and cultural tests, it was possible to identify most of the isolated strains as Vibrio anguillarum . Strains with intermediate characteristics, above-all positive saccharose, proved to be numerous. The authors discuss the occurrence, in particular environments such as those being studied, of atypical or intermediate vibrio strains which are difficult to classify. |
Tipo: Text |
Palavras-chave: Vibrio; Microbiological culture; Bacteria; Food; Minced products; Fish ponds; Sea water; Identification; Marine aquaculture; Bacteria collecting devices; Microbiological analysis. |
Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-997.pdf |
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Sarradin, Pierre-marie; Caprais, Jean-claude; Riso, Ricardo; Kerouel, Roger; Aminot, Alain. |
Water samples were collected around the communities of a hydrothermal mussel, Bathymodiolus sp., in the Lucky Strike (1700 m depth) and Menez Gwen (850 m depth) areas, Mid Atlantic Ridge, and analysed for chemical constituents. The environment surrounding the organisms consists in sea water (88 to 100%) mixed with hydrothermal fluid with pH between 6.2 and 8, Sigma S (H2S + HS-) concentrations from 0 to 62 mu mol l(-1). High dissolved organic carbon (DOC) concentrations suggest a highly productive ecosystem. Production of ammonium and DOG, consumption of nitrate and sulfide in the vicinity of the organisms are among the environmental changes found in relation with local biological activity. Concentrations of Cu and Pb were high, implying that the organisms... |
Tipo: Text |
Palavras-chave: Environment; Sea water; Hydrothermal vents; Mussels. |
Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/00147/25847/23968.pdf |
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Bodoy, A; Geiaron, P; Garnier, Jacqueline; Heurtebise, S. |
Two different biomasses (100 g multiplied by m super(-2) and 1 kg multiplied by m super(-2)) of oysters were put in identical sea-water ponds, thus leading to different trophic conditions, corresponding to rearing techniques. Changes in growth, biochemical composition and sexual maturation were recorded for two age groups. The first one included 9 month-old oysters and the second one 21 month-old oysters, at the beginning of the experiment. For both age groups, significant differences were observed in growth and biochemical composition. Lipids were accumulated faster for the lower biomass. However, the only difference concerning glycogen was observed on the older oysters. They showed a peak at the lowest biomass and a decrease at the larger biomass. Sexual... |
Tipo: Text |
Palavras-chave: Crassostrea gigas; Bivalvia; Sea water; Oyster culture; Glycogen; Age; Chemical composition; Lipids; Biochemistry; Sexual maturity; Rearing; Pond culture; Biomass; Growth; Density. |
Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/1992/acte-916.pdf |
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Davies, Peter; Evrard, Guy. |
Polyurethanes are frequently used in underwater applications. They are required to resist the marine environment over long periods of immersion but the multiplicity of resin formulations makes material selection difficult. Accelerated tests are essential to guarantee long term integrity. This paper presents results from an experimental study in which polyurethane samples of two hardnesses, 40 and 90 Shore A, have been subjected to immersion in artificial sea water for periods up to two years at temperatures from 50 to 100 degrees C. In parallel samples have been immersed at sea in the Brest Estuary for up to five years. Mechanical properties have been measured on tensile specimens after ageing. The accelerated test results and FTIR analysis indicate that... |
Tipo: Text |
Palavras-chave: Accelerated test; Sea water; Ageing; Marine; Polyurethane. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2822.pdf |
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Registros recuperados: 39 | |
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