University of the Littoral Opal Coast

About: University of the Littoral Opal Coast is a education organization based out in Dunkirk, France. It is known for research contribution in the topics: Catalysis & Dielectric. The organization has 1242 authors who have published 2383 publications receiving 46230 citations. The organization is also known as: ULCO.

Seasonal relative abundance of fish larvae inshore at Îles Kerguelen, Southern Ocean

Abstract: Ichthyoplankton sampling was conducted seasonally with 36 surveys between spring 1989 and spring 1992 in four bays in the Kerguelen archipelago: Morbihan, Baleiniers, Choiseul and Audierne. Golfe des Baleiniers is open to the shelf whereas Choiseul and Audierne are long fjords. Golfe du Morbihan is a very large and protected area open to the shelf at its eastern end. Larvae of neritic species were abundant outside whereas larvae of inshore species were abundant inside the Golfe du Morbihan. Larval Lepidonotothen squamifrons were detected during summer every year whereas larvae of Champsocephalus gunnari were observed in only two years, mainly in the northern coastal zone. For both species, our results support coastal spawning grounds in addition to those on the shelf slope. Larvae of the mesopelagic fish Krefftichthys anderssoni were dominant primarily during winter; this was linked to homogenisation of the water column over the shelf and the coastal zone. Larvae of Notothenia cyanobrancha were present throughout the year everywhere, which is linked to the year long pelagic earlylife-history phase.

Estimating the Atmospheric Water Vapor Content from Sun Photometer Measurements

Abstract: The differential absorption technique for estimating columnar water vapor values from the analysis of sunphotometric measurements with wide- and narrowband interferential filters centered near 0.94 μm is discussed and adapted. Water vapor line and continuum absorption calculations are obtained through the procedures included in the radiative transfer code LOWTRAN-7. The accuracy of these calculations is assessed through comparisons with a line-by-line code associated with an updated version of the Clough–Kneizys–Davies continuum. The effects of aerosols and aging of filters on the wide-to-narrow measurements ratio is analyzed. Columnar water vapor retrievals are based upon a search inside a 4D table that contains wide-to-narrow ratios corresponding to combinations of values assumed by four independent variables: sun zenith angle, spectral dependence of aerosol extinction, turbidity level, and the columnar water vapor itself. This table is calculated by taking into account the wide and narrow filt...

Catalytic properties of beta zeolite exchanged with Pd and Fe for toluene total oxidation

Abstract: Dealuminated beta zeolites exchanged with Pd and Fe were prepared to investigate the influence of iron and dealumination on the activity and selectivity of Pd/BEA zeolite for toluene total oxidation. The specific areas determined by BET method and EPR studies allowed to know that the palladium would be more easily agglomerated on the BEA than on the DBEA. Moreover, a quantification of the palladium saturation on the BEA zeolite was deduced by EPR. Effects of dynamic and static oxidation and weak and strong reduction treatments were studied by EPR. Several isolated and interacted Pd + species and hole centers were detected. The Pd was much reduced after the catalytic test in dealuminated and Fe doped samples. This result could be directly correlated to the catalytic deactivation. The deactivation could be also explain by the type of coke deposed on the catalyst and by the hydroscopic behavior of the samples. Addition of Fe or dealumination could prevent the deactivation and then lead to better catalysts for VOCs oxidation.