Le Budget et le Deficit.

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Elimination de la matière organique biodégradable par ultrafiltration

Les installations de production de la Compagnie des Eaux de banlieue (CEB) au Mont Valérien traitent l'eau de Seine en aval de Paris sur 2 filières de potabilisation comprenant pour la première (50 000 m3/J) une préozonation, une coagulation au sels d'Aluminium (Aqualenc), une décantation (super pulsator Degrémont), une filtration sur sable, une ozonation, une filtration sur charbon actif en grains (CAG) et une désinfection finale au bioxyde de chlore, et pour la deuxième, une filtration lente sur sable (80 000 m3/j) dite filtration "Chabale".Dans le cadre du remplacement de la filière "Chabale", une unité de démonstration (8 m3/h) eomprenaut une addition de charbon actif en poudre (CAP) avant ultrafiltration sur membrane a été mise en route.Dans cette étude, une comparaison du traitement conventionnel physico-chimique de l'usine et du nouveau procédé d'ultrafiltration a été effectuée. Pour cela, un suivi du carbone organique total et une évaluation du potentiel de reviviscence ont été réalisés en différents points des chaînes de traitement. La matière organique biodégradable (MOB) a été mesurée par la méthode Werner (1980).Les premiers résultats montrent :- l'élimination des MOB est comparable pour les différents procédés;- toutefois, la nature des MOB est sensiblement affectée à chaque type de traitement (ozonation, addition de CAP, filtration sur sable ou sur CAG)."Compagnie des Eaux de Banlieue" water facilities located at the Mont-Valérien treat the Seine river water downstream Paris. A first facility (5000 m3/day) includes the following processes : preozonation, coagulation, settling, sand filtration, postozonalion, GAC filtration and a final desinfection (CIO2). A second one consists in a biological sand filtration (80000 m3/day). An ultrafiltration demonstration plant including a CAP addition into the recirculation loop is currently tested on a small scale (8 m3/h) to compare the conventional treatments with new ultrafiltration process.In this study, the TOC removal as well as the biodegradable organic matter (BOM) removal are evaluated on the different processes. The BOM has been assessed by the Werner methodology (1980).During the cool season (october-january) all the biodegradable organic matter were removed by the clarification process (preozonation + coagulation decantation + sand filtration). More than 90 % of the BOM were also removed by the ultrafiltration demonstration plant (including granular activated carbon) although the addition of preozonation slightly increases the effluent BOM concentrations and modifies its composition. 80 % of the dissolved organic compounds were removed by the preozonation + ultrafiltration + powder treatment line. This performance should be compared with the 70 % removal obtained with conventional treatments.This study demonstrate that the combination 03 + UF + CAP can advantageously replace traditional treatment such as preozonation + coagulation clarification + ozonation + granular activated carbon + desinfection

III.5 Stellar classification in CoRoT faint stars fields

This book is dedicated to all the people interested in the CoRoT mission and the beautiful data that were delivered during its six year duration. Either amateurs, professional, young or senior researchers, they will find treasures not only at the time of this publication but also in the future twenty or thirty years. It presents the data in their final version, explains how they have been obtained, how to handle them, describes the tools necessary to understand them, and where to find them. It also highlights the most striking first results obtained up to now. CoRoT has opened several unexpected directions of research and certainly new ones still to be discovered

IV.3 The wealth of stellar variability

This book is dedicated to all the people interested in the CoRoT mission and the beautiful data that were delivered during its six year duration. Either amateurs, professional, young or senior researchers, they will find treasures not only at the time of this publication but also in the future twenty or thirty years. It presents the data in their final version, explains how they have been obtained, how to handle them, describes the tools necessary to understand them, and where to find them. It also highlights the most striking first results obtained up to now. CoRoT has opened several unexpected directions of research and certainly new ones still to be discovered

Residual stress measurements of alumina-zirconia ceramics by time-of-flight neutron diffraction

Neutron strain scanning and Rietveld analysis were used to study the residual stresses in Al2O3/Y-TZP ceramic composites fabricated by different green processing techniques (a novel tape casting and conventional slip casting) and with different zirconia content. The results show that the residual stresses in zirconia particulates are tensile and the ones in alumina matrix are compressive, with almost flat through-thickness residual stress profiles in all bulk samples. The residual stresses for both phases were mainly dependent on the zirconia content, irrespective of the measurement direction and the fabrication process

Oscillating red giants in the CoRoT exo-field: Asteroseismic mass and radius determination

Context. Observations and analysis of solar-type oscillations in red-giant stars is an emerging aspect of asteroseismic analysis with a number of open questions yet to be explored. Although stochastic oscillations have previously been detected in red giants from both radial velocity and photometric measurements, those data were either too short or had sampling that was not complete enough to perform a detailed data analysis of the variability. The quality and quantity of photometric data as provided by the CoRoT satellite is necessary to provide a breakthrough in observing p-mode oscillations in red giants. We have analyzed continuous photometric time-series of about 11 400 relatively faint stars obtained in the exofield of CoRoT during the first 150 days long-run campaign from May to October 2007. We find several hundred stars showing a clear power excess in a frequency and amplitude range expected for red-giant pulsators. In this paper we present first results on a sub-sample of these stars. Aims. Knowing reliable fundamental parameters like mass and radius is essential for detailed asteroseismic studies of red-giant stars. As the CoRoT exofield targets are relatively faint (11-16 mag) there are no (or only weak) constraints on the star's location in the H-R diagram. We therefore aim to extract information about such fundamental parameters solely from the available time series. Methods. We model the convective background noise and the power excess hump due to pulsation with a global model fit and deduce reliable estimates for the stellar mass and radius from scaling relations for the frequency of maximum oscillation power and the characteristic frequency separation.Comment: 10 pages, 7 figures, accepted for publication in A&