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A new method was employed for the preparation of a set of lanthanum cobaltites of general formula La1-xMxCoO3+ with M=Ce, Eu and x=0, 0.05, 0.1, 0.2. All the samples so prepared showed nanostructured, thermally very stable and characterised by highly crystalline perovskite-like structure and high surface area. Their activity as catalysts for the catalytic flameless combustion of methane was by ca. one order of magnitude higher than that of their analogues, prepared through the usual calcination-milling procedure.Adsorption of oxygen was accompanied by formation of paramagnetic species. Desorption of preadsorbed oxygen was dependent on the nature of the doping element and on the value of the stoichiometric coefficient x of their formula. A correlation between the temperature of the maximal rate of oxygen release and catalytic activity was found. The following scale of activity for the title reaction vs. x values could be set up: 0.1 Ce > 0.05 Ce > 0 > 0.05 Eu > 0.1 Eu  0.2 Ce. The higher activity of Ce-doped catalysts as compared to those doped with Eu was found to be related to the strength of the bond between oxygen and Co ions.

A flame pyrolysis (FP) procedure has been set up for the preparation of V/Al/O catalysts to be employed for the oxidative dehydrogenation of propane to propylene. The samples have been characterised by means of various techniques (FT-IR, Raman, EPR, ICP-MS, TGA, XRD, SEM) and their catalytic activity has been evaluated in two different operating modes, i.e. under anaerobic conditions and by co-feeding oxygen. The particle size distribution became progressively more homogeneous with increasing V concentration, due to the catalytic effect of the V ions during the FP synthesis. Some V2O5 segregation was observed even at low V loading. However, higher V dispersion was attained with respect to a reference sample prepared by impregnation of the FP-prepared alumina support. 2The increase of V concentration always led to an improvement of propane conversion, though selectivity showed different trends depending on the operating conditions. The comparison with the sample prepared by impregnation showed similar catalytic activity, with a bit higher selectivity for the FP-prepared sample under anaerobic conditions.

A set of LaMnO3 and LaCoO3 catalysts was prepared through different synthesis procedures. The selected techniques included the sol-gel method, flame hydrolysis from aqueous solution, complexation through EDTA and solid-state reaction. The last was accomplished through reactive grinding by ball milling either in a vibration mill or in a planetary mill. EDTA complexation was applied for LaCoO3 only and did not improve significantly catalyst activity or stability, with respect to other techniques. Ball milling never allowed obtaining a pure perovskitic phase, at least under the most energetic grinding conditions permitted by our apparatus. The highest activity for the catalytic flameless combustion of methane was obtained with the sol-gel prepared samples, though thermal resistance revealed insufficient for high temperature applications. A bit lower activity, but coupled with good thermal stability was obtained with the samples prepared through flame hydrolysis.

The amount of the trace elements As, Ba, Cd, Cr, Cu, Hg, Li, Mn, Ni, Pb, Rb, Se, Sr, and Zn was measured in top soils and edible mushrooms, Boletus edulis, Macrolepiota procera, collected at five distinct green microhabitats inside the Lucca province, North-Central Italy (years 2008-2009). Results showed a top soil element content within the Italian statutory limits. Concerning the amount of mushroom elements, we observed significant species-differences obtaining higher levels of Ni, Rb, and Se in B. edulis or As, Pb, Cu in M. procera. Bioaccumulation factors (BCFs: element in mushroom/element in soil) resulted species-dependent and element-selective: in particular, B. edulis preferentially accumulated Se (BCFs varying from 14 to 153), while M. procera mainly concentrated Cu (BCFs varying from 5 to 15). As well, both species displayed between-site BCF differences. By a multivariate principal component approach, cluster analysis (CA), we could resolve two main clusters of soil element composition, corresponding to the most ecologically divergent sites. Besides, CA showed no cluster relating to element contents of B. edulis at the different collection sites, while a separation in groups was found for M. procera composition with respect to harvesting locations, suggesting uptake systems, in this saprotrophic species, sensitive to microhabitat. Regarding consumer safety, Cd, Hg, Pb levels resulted sometime relevant in present samples, never reaching values from current literature on mushrooms collected in urban-polluted areas. Our findings encourage a deeper assessment of the molecular mechanisms of metal intake by edible mushrooms, encompassing genetic biochemical and geo-ecological variables, with particular awareness to element bioavailability in soils and fungi.

The formation of social bonding is fundamental for several animals, including humans, for its relevant and obvious impact upon reproduction and, thus, survival of the species. Recent data would suggest that oxytocin might be one of the mediators of this process. Given the paucity of data on the possible involvement of oxytocin in human attachment, the present study was aimed to explore the possible relationships between the plasma levels of this neuropeptide and romantic attachment in healthy subjects. Forty-five healthy subjects who volunteered for the study, were included in the study. The romantic attachment was assessed using the Italian version of the so-called "Experiences in Close Relationships" (ECR), a self-report questionnaire for measuring this parameter in adults. The results showed that attachment anxiety and oxytocin are positively linked in romantic attachment to a statistically significant degree (r = 0.30, p = 0.04), that is, the higher the oxytocin levels the higher the score on the anxiety scale of the ECR. The authors suggest the hypothesis that this link represents one of the biological processes resulting in those rewarding emotions related to romantic attachment.

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Three SrTiO 3±δ catalysts have been compared. One of them (T3) was prepared by the traditional sol-gel procedure, the other two through the flame hydrolysis (FH) technique, in the presence of either 1.5 mol excess of citric acid (sample T2) or 3 mol excess of tartaric acid (sample T1) as complexing agent in the precursor solution. All the catalysts possessed the perovskite-like structure, with some SrCO 3 as impurity. T1 was more crystalline than the other two samples and showed the most active as catalyst for the flameless combustion of methane. Isolated Ti 3+ ions were found in T3 by EPR analysis, while different EPR features were noticed with T1 and T2 and attributed to Ti 4+ /O 3 − . A high concentration of isolated Ti 3+ ions was observed with T1, accompanied by Ti 4+ /O 3 − and by other paramagnetic species, probably Ti 4+ /O − and Sr 2+ /O − , not observed with the other samples. This difference between the samples T1 and T2, likely connected with the different temperature attained during the FH preparation process with the two different complexing agents, can explain the higher oxidising activity of the T1 sample.