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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.dsr.2007.12.008 Byline: Fabrizio D'Ortenzio (a), David Antoine (a), Salvatore Marullo (b) Keywords: CO.sub.2 dynamics; Ocean remote sensing; Mediterranean Sea; Ocean mixed layer Abstract: The air-sea CO.sub.2 flux, the carbon export to the deep layers, and more generally the carbon budgets are presently poorly characterized in the Mediterranean Sea. An approach to the simulation of these fluxes at regional scale is proposed, based on an array of unconnected one-dimensional (1D) physical-biological-chemical coupled models. The rationale is to massively assimilate satellite information, on one hand to derive accurate surface heat fluxes, and, on the other hand, to implicitly account for the horizontal processes not explicitly represented in the 1D scheme. This method is applied here to simulate the upper ocean physical and biogeochemical dynamics of the entire Mediterranean Sea over the years 1998-2004, and at a 0.5[degrees] spatial resolution. The mixed-layer annual cycles are validated against the values determined from a database of in situ temperature profiles, demonstrating the validity of the approach in various physical regimes. A validation of the simulated annual cycles of the total inorganic carbon (TCO.sub.2) and of the carbon dioxide partial pressure (pCO.sub.2) is presented at a measurement site in the northwestern Mediterranean where both properties were determined in 1998-1999 and in 2003-2004. An additional validation of the pCO.sub.2 fields is presented using along-track data collected during the 'Productivite des Systemes Oceaniques Pelagiques' (PROSOPE) cruise. The basin-scale air-sea carbon budget derived from the model outputs shows that the Mediterranean Sea, over the study period, is close to equilibrium with the atmosphere, with a slight sink for the atmospheric CO.sub.2. This is in agreement with the results previously obtained via indirect methods and is supported here by a series of sensitivity studies. A detailed analysis of the pCO.sub.2 and TCO.sub.2 seasonal distributions in the Mediterranean Sea is provided for the first time. It shows that the biological processes play a major role in shaping the pCO.sub.2 seasonal evolution in the eastern and western basins. Author Affiliation: (a) Laboratoire d'Oceanographie de Villefranche, Universite Pierre et Marie Curie et CNRS, Quai de La Darse, BP 8, 06238 Villefranche sur Mer Cedex, France (b) Centro Ricerche Frascati, Ente per le Nuove tecnologie, l'Energia e l'Ambiente Frascati, Italy Article History: Received 27 September 2006; Revised 30 November 2007; Accepted 12 December 2007

Within the Copernicus Marine Environment Monitoring Service (CMEMS), a new operational MEDiterranean Diurnal Optimally Interpolated SST (MED DOISST) product has been developed. This product provides hourly mean maps (Level-4) of sub-skin SST at 1/16° horizontal resolution over the Mediterranean Sea from January 2019 to present. The product is built by combining hourly SST data from the Spinning Enhanced Visible and InfraRed Imager (SEVIRI) on board Meteosat Second Generation and model analyses through optimal interpolation. SEVIRI and model data are respectively used as the observation source and first-guess. The differences between satellite and model SST are free, or nearly free, of any diurnal cycle, thus allowing them to be interpolated in space and time using satellite data acquired at different times of the day. The accuracy of the MED DOISST product is assessed here by comparison against surface drifting buoy measurements, covering the years 2019 and 2020. The diurnal cycle reconstructed from DOISST is in good agreement with the one observed by independent drifter data, with a mean bias of 0.041 ± 0.001 K and root-mean-square difference (RMSD) of 0.412 ± 0.001 K. The new SST product is more accurate than the input model during the central warming hours, when the model, on average, underestimates drifter SST by one tenth of degree. The MED DOISST product is also able to reproduce accurately the extreme diurnal warming events frequently observed in the Mediterranean Sea, which may reach amplitudes larger than 5 K during the warm season. This product can contribute to improve the prediction capability of numerical weather forecast systems (e.g., through improved forcings/assimilation), as well as the monitoring of surface heat budget estimates and temperature extremes which can have significant impacts on the marine ecosystem. The full MED DOISST product (released on 04 May 2021) is available upon free registration at https://doi.org/10.25423/CMCC/SST%5FMED%5FPHY%5FSUBSKIN%5FL4%5FNRT%5F010%5F036 (Pisano et al., 2021). The reduced subset used here for validation and review purposes is openly available at https://doi.org/10.5281/zenodo.5807729 (Pisano, 2021). [ABSTRACT FROM AUTHOR]

Oligothiophene derivatives play a central role in the formulation of materials used in devices in the field of organic electronics. In this work, we report the results of the study of UV-vis absorption and fluorescence spectra, in several solvents, of a series of oligothiophenes recently synthesized in our laboratory. The studied oligothiophenes present different structures due to several factors: the donor–acceptor (D–A) or acceptor–donor–acceptor (A–D–A) architecture, the number of thiophene rings in the backbone (ranging from three to eight), the number and position of solubilizing octyl chains in the backbone, and the type of acceptor moieties (from Knoevenagel condensation either with ethyl cyanoacetate or 3-ethylrhodanine). Since solvents with different polarities were adopted, we provide a detailed analysis on the observed positive and negative solvatochromism effects depending on the symmetry of the oligomers, the lengths of the backbones and the kind of acceptors adopted. Moreover, the electrochemical synthesis of a new donor–acceptor oligothiophene (which can be assumed as a model compound) by anodic dimerization is reported, along with the voltammetric analysis of the obtained product. [ABSTRACT FROM AUTHOR]

We document the development and public release of a new dataset (1997-2018), consisting of global maps of the Forel-Ule index, hue angle and Secchi disk depth. Source data comes from the European Space Agency (ESA) Ocean Colour (OC) Climate Change Initiative (CCI), which is providing merged multi-sensor data from the mid-resolution sensors in operation at a specific time from 1997 to the present day. Multi-sensor satellite datasets are advantageous tools for ecological studies because they increase the probabilities of cloud-free data over a given region, as data from multiple satellites whose overpass times differ by a few hours are combined. Moreover, data merging from heritage and present satellites can expand the duration of the time series indefinitely, which allows the calculation of significant trends. Additionally, data are remapped consistently and analysis-ready for scientists. Also, the products described in this article have the exclusive advantage of being linkable to in-situ historic observations and thus enabling the construction of very long time series. Monthly data are presented at a spatial resolution of ~4 km at the equator and are available at PANGAEA, https://doi:10.1594/PANGAEA.904266 (Pitarch et al., 2019a). Two smaller and easier to handle test datasets have been produced from the former: a global dataset at 1 degree spatial resolution and another one for the North Atlantic at 0.25 degree resolution. [ABSTRACT FROM AUTHOR]

Current concerns for sustainability and the environment make low‐impact materials desirable for environmental remediation and, in particular wastewater treatment. We obtained supramolecular gels of l‐amino acids in the deep eutectic solvent formed by choline chloride and phenylacetic acid. After gel characterization, and investigating gel–sol transition temperatures, gelation kinetics, rheological properties, and morphology, the gels were applied as sorbents to remove cationic dyes from aqueous solutions. The effects of the pH, dye nature, volume, and concentration of wastewater were analyzed, and the best result was obtained with a l‐phenylalanine‐based eutectogel. It can be reused for at least 9 times without losing efficiency, also with dye mixtures. Interestingly, this gel can be loaded onto columns to decolorize flowing solutions, achieving 85 % of removal efficiency in only 10 minutes and allowing its reuse for at least 4 cycles. In terms of adsorption capacity, this eutectogel is competitive with efficient gel‐based dye sorbent systems, with a value 1930 mg/g reached at a high concentration of rhodamine B 479 mg/L. [ABSTRACT FROM AUTHOR]

The importance of electronic effect of the substituents present on the aromatic ring is evaluated by considering both electron-withdrawing and donor substituents and the importance of the steric effects of the substituents both para- and ortho-substituted benzoic acids is analyzed. The ortho-steric effect has operated differently in water and in the aromatic ionic liquid, determining in this solvent medium a particular behavior for ortho-substituted benzoic acids.

The kinetics of nucleophilic aromatic substitution of three nitrothiophene derivatives in different [1-butyl-3-methylimidazolium][[N.sub.3]]/ionic liquid binary mixtures are analyzed. The studies have shown that a simple linear dependence of the pseudo-first kinetic constant from nucleophile concentration is detected as a consequence of the ability of all solvent media to favor the leaving group departure.