Consulta: creatorFacets:"Farah, W."
Registros recuperados: 3
Data/hora: 02/06/2024 18:53:11

Development of alginate hydrogels active against adhesion of microalgae
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Nassif, L. Abi; Rioual, S.; Trepos, Rozenn; Fauchon, M.; Farah, W.; Hellio, C.; Abboud, M.; Lescop, B.
Microorganisms have the ability to settle on nearly all man-made surfaces in contact with seawater and subsequently to form biofilm. Biofilms control and removal is necessary in the sectors of maritime transport, energy... In this work, we present the development of new pure calcium, zinc or copper alginate, but also mixed Ca/Cu and Ca/Zn alginate hydrogels. These materials have been evaluated for their potential inhibition of adhesion of two key biofilm-forming microalgae Halamphora coffeaeformis and Cylindrotheca closterium). All the tested materials have presented high adhesion inhibition about 80%). Copper-base materials present a high toxicity against H. coffeaeformis. Pure zinc alginate is also toxic for this strain. However, the addition of calcium...
Tipo: Text
Palavras-chave: Biofilm; Adhesion; Alginate; Zinc; Biomaterials; Microalgae.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00605/71671/70168.pdf

Reduction of potential ennoblement of stainless steel in natural seawater by an ecofriendly biopolymer
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Abi Nassif, L.; Rioual, S.; Farah, W.; Hellio, C.; Fauchon, M.; Trepos, R; Abboud, M.; Diler, E.; Thierry, D.; Lescop, B.
The effect of biofilm formation on passive stainless steel in seawater environments is of primary importance since it leads to potential ennoblement of surfaces and subsequently to localized corrosion such as pitting and crevice corrosion. This study aims at developing an ecofriendly alginate biopolymer containing both non-toxic calcium and a limited amount of biocidal zinc ions which inhibits this effect. For this purpose, calcium alginate containing less than 1 % of zinc ions localized in the vicinity of the steel surface in natural and renewed seawater is demonstrated to reduce significantly the ennoblement process of steel. After 1 month of immersion, a mass loss of only 4 % of the active material is observed authorizing thereby long-term protection of...
Tipo: Text
Palavras-chave: Biopolymer; Steel; Ennoblement; Antimicrobial; Alginate; Biofilm.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00604/71607/73083.pdf

Development of a Resonant Microwave Sensor for Sediment Density Characterization
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Mansour, Rassoul; Rioual, S.; Lescop, B.; Talbot, P.; Abboud, M.; Farah, W.; Tanné, G.
In this study, a sensor based on the development of a planar antenna immersed in sediments dedicated to water content monitoring in this type of material is proposed and experimentally validated. It is produced by a conventional Printed Circuit Board (PCB) manufacturing process on a double-sided metalized FR4 substrate. The sensitivity of the sensor is ensured by the variation of the real part of the complex dielectric permittivity of sediments with water content at around 1 GHz. As shown, in this frequency range, electrode polarization and Maxwell–Wagner polarization e ects become negligible, leading to only a bulk water polarization sensitivity. The sensor operates in the reflection mode by monitoring the variation of the resonant frequency as a function...
Tipo: Text
Palavras-chave: Resonant sensor; Water content; Dielectric characterization; Microwave; Antenna; Sediments.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00610/72167/70939.pdf