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Moscato grapes give very aromatic musts and wines, characterized by the presence of monoterpenoids. The Farroupilha region situated in the highlands of South Brazil, is responsible for 50% of Brazilian Moscato wines production, and obtained its Geographical Indication (GI) in 2015. Brazilian Moscato wines are produced with several varieties, mainly Moscato Branco, Moscato Bianco R2 and Moscato Giallo. The objective of this study was to characterize the aromatic profile of wines produced with the three varieties. Microvinifications were conducted with grapes collected in three vineyards located in Farroupilha. Volatile compounds were evaluated using gas chromatography, and sensory characteristics were determined by a panel of enologists using a specific descriptive chard. Moscato Giallo wines exhibited the highest concentrations of ethyl acetate, 2-phenylethanol, isoamyl acetate, linalool, and α-terpineol; Moscato R2 wines showed the highest concentrations of ethyl decanoate and nerol, while Moscato Branco wines, the most representative variety of Brazilian sparkling Moscato wines, exhibited the highest concentrations of ethanal and ethyl hexanoate, and intermediary concentrations of the other compounds. In sensory analysis, the three varieties exhibited pear, pitanga, rosemary, and citric fruits aromas, but in general, Moscato Giallo and Moscato R2 were more intense, while Moscato Branco showed the highest acidity.

NMR T1 relaxation times have been measured for 13C nuclei in the alkyl chains of symmetric tetra-n-alkylstannanes dissolved in CDCl3. The results are interpreted in terms of conformational transitions occurring in the aliphatic chains superimposed to rotational diffusion of the whole molecule. A comparison with analogous tetra-n-alkylammonium salts is performed. Differences are ascribed to changes in the overall rotational diffusion deriving from effects of charge upon formation of ion-pairs and larger aggregates.

The conformational dynamics of alkyl chains is usually analysed within the framework of the rotational isomeric state (RIS) approximation, where only the conformers corresponding to the configurational potential minima are considered, and torsional fluctuations about the minima are ignored. In order to test the validity of this procedure, 13 C NMR T 1 relaxation times have been measured in the series of symmetric tetra- n -alkylammonium ions (C N H 2 N +1 ) 4 N + , with N = 8, 10, 12, 16 and 18, and compared with theoretical results predicted by the RIS model. Spin relaxation rates of the terminal carbon atoms show a tendency to level off for increasing chain length, in contrast with the monotonic increase predicted by the RIS model. The experimental behaviour reveals that deviations from RIS results appear for chains with more than ten carbon atoms.

The effectiveness of electrochemical methods in purification of synthetic wastewaters containing bisphenol-A has been tested. The role of electrode material and electrolysis parameters have been considered. The kinetics of bisphenol oxidation have been followed using different analytical techniques and a degradation mechanism has been proposed.