Evidence of a cubic iron sub-lattice in t-CuFe2O4 demonstrated by X-ray Absorption Fine Structure

Copper ferrite, belonging to the wide and technologically relevant class of spinel ferrites, was grown in the form of t-CuFe2O4 nanocrystals within a porous matrix of silica in the form of either an aerogel or a xerogel, and com-pared to a bulk sample. Extended X-ray absorption fine structure (EXAFS) spectroscopy revealed the presence of two different sub-lattices within the crystal structure of t-CuFe2O4, one tetragonal and one cubic, defined by the Cu2+ and Fe3+ ions respectively. Our investigation provides evidence that the Jahn-Teller distortion, which occurs on the Cu2+ ions located in octahedral sites, does not affect the coordination geometry of the Fe3+ ions, regardless of their location in octahedral or tetrahedral sites

Comparison of PAH degradation by autochthonous microbial communities in sediments of different Mediterranean port areas

PAHs are a class of organic compounds which by their nature (low volatility, low solubility, recalcitrance to biological degradation), tend to accumulate in marine sediments. This study investigated the natural PAH degradation by the autochthonous microbial communities present in sediments of three different Mediterranean tourist ports: Cagliari (Italy), El Kantaoui (Tunisia) and Heraklion (Greece). Bacterial populations able to degrade petroleum hydrocarbons are present in surface sediments from the port areas. Moreover, a spatial variation is evident among Heraklion port sectors according to their different uses. Microcosms were set up with the aim to evaluate aerobic and anoxic phenanthrene (Phe) degradation. The autochthonous microbial communities were able to almost-fully degrade Phe, in aerobic conditions, in 56 days, while in 120 days, no relevant degradation was found in anoxic conditions, except for Heraklion microcosms

Characterization of bacterial communities in tourist ports in the Mediterranean Sea Basin

Port areas pose major concerns due to the presence of toxic pollutants and to their harmful effects on the marine ecosystems and human ealth. Hydrocarbon contamination, associated with the heavy boat traffic and related facilities, is one of the major environmental problems. Moreover, tourist ports are subject to seasonal massive impact. This work is part of a multidisciplinary characterization of the tourist ports of Cagliari IT, El Kantaoui TN, Heraklion GR, carried out within the MAPMED project aimed to improve the environmental sustainability of tourist coastal areas in the Mediterranean Sea Basin with regard to monitoring and reduction of marine hydrocarbon pollution. Two sampling campaigns were carried out during winter and late spring, before the touristic season, and a third one is planned after the touristic season. In each port, samples of seawater, superficial and anoxic sediments were collected at different stations. A combination of culture-dependent (MPN of different metabolic groups) and -independent approaches (T-RFLP of 16S rRNA gene and other genes) has been employed in order to define the seasonal and spatial variations in the Bacteria and Archaea communities