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Complex fluids, widely used in many industrial applications, typically include amphiphilic molecules such as surfactants. Most of the surfactants used in products for fabric care, home care, and beauty care, such as detergents, or cosmetics have a complex microstructure and rheological behavior. At high concentrations, surfactant solutions self-assemble into lyotropic mesophases exhibiting complex rheology and viscoelasticity relevant for processing.1, 2 These molecules can rearrange themselves depending on both chemical structure and the process. Furthermore, the microstructure of the system strongly affects the properties of the finished product, which are the determining factors for the specific application. It is, therefore, necessary to identify and study the chemical-physical processes that involve such systems. Industrial processing of surfactant-based materials typically includes a water dissolution step. It is well established that both physicochemical and rheological parameters, such as raw material chemistry, type of solvent, temperature and flow conditions, play a key role in the dissolution process3. However, the mechanisms governing the dissolution process are not well understood. This explains the great interest in the dissolution of complex molecules in flow or in static conditions. As a matter of fact, understanding the dissolution of the concentrated surfactant solutions in different solvents is of fundamental importance for their effective industrial application. In this work video microscopy will be used to investigate dissolution in well-controlled static conditions, and the sample microstructure changes will be observed; a microfluidic device will be rearranged to evaluate the effect of specific flow conditions with the aim to understand which is the controlling factor of the phenomenon and see differences from static results; in order to observe the process in a larger scale, a simple lab scale test will be set up and a Raman tool used to characterize the process in beaker with the aims to build a model to quantify the dissolution process and a correlation of this method with pilot plant scale test.

Trace element accumulation in the lichen Pseudevernia furfuracea (L.) Zopf was studied in the district of Acerra (province of Naples, southern Italy), one of the points forming Italy's Triangle of Death. P. furfuracea thalli, collected from Mt. Faito (province of Naples), were transplanted and exposed in bags at different sites in Acerra district, classified into three different site types (urban, rural and industrial). We aimed to test the hypothesis that P. furfuracea, when transplanted in the district of Acerra, would respond to air pollution accumulating trace elements and that element concentrations in the exposed lichens were different in relation to the three different environments, characterised by different pollution sources. Samples were exposed for six months, periodically collected and examined by ICP MS spectrometer assays to measure concentrations of 10 trace elements (Al, As, Cd, Cr, Cu, Fe, Mn, Pb, V and Zn). The exposed samples showed increases in concentrations of all the examined elements; the trace element concentrations were evaluated by calculating exposed to control (EC) ratios, for each site and each trace element, to better understand the accumulation rates. EC ratios were evaluated after 3 and 6 month exposures, at the end of spring and summer respectively: 6 month EC values were the highest. The urban sites showed EC ratios generally higher than industrial and rural; the most accumulated elements were Pb and Cu (at the urban sites), Cu and Zn (at the industrial sites), and Cu and As (at the rural sites). The chemical data were then processed using a multivariate approach (ordination, PCA) to better understand environmental gradients. Bioaccumulation data and PCA analysis showed the sampling sites separated by different trace element abundance. Trace element abundance patterns in the three site types are discussed in relation to the land use and the pollution sources.

Dagli anni ‘60 licheni e briofite vengono utilizzati a livello locale, nazionale o continentale per valutazioni di impatto ambientale dovuto ad attività umane e industriali; la maggior parte degli studi sulle briofite come bioindicatori sono stati rivolti alla stima dei cambiamenti qualitativi e quantitativi della vitalità, presenza, copertura e distribuzione di specie, correlabili alla presenza nell’atmosfera di gas fitotossici, elementi in traccia e altri contaminanti immessi nell’atmosfera da fonti naturali e antropogeniche (1). La valutazione di biodiversità di una regione comprende tradizionalmente la valutazione della biodiversità ecologica (diversità di ambienti), e della biodiversità specifica (numero e frequenza specie) stimata, almeno per la componente vegetale, con metodi basati sul rilievo fito-sociologico. Il recente impiego di markers molecolari applicati allo studio di popolazioni di piante vascolari e muschi (2), ha reso possibile stimare i livelli di diversità genetica intraspecifica per valutare lo stato di conservazione delle comunità naturali e fare previsioni su cambiamenti in atto. Studi effettuati mediante rilievi fitosociologici sulla vegetazione briofitica epifita di Quercus ilex nella regione Campania, hanno messo in evidenza che, nei siti urbani, il numero di specie e l’IAP (Index of Air Purity) sono più bassi, che le specie acrocarpe prevalgono sulle pleurocarpe e la riproduzione sessuale è meno frequente, evidenziando, nei siti più disturbati, uno stato pioniere della comunità briofitica che può essere permanente (3). La struttura e la variabilità genetica del muschio Leptodon smithii campionato in alcuni siti della Campania caratterizzati da diverso grado di disturbo, sono state analizzate utilizzando marcatori nucleari ISSR (internal simple sequence repeat) e confrontate con i dati fitosociologici ed ecologici, evidenziando numerosi parallelismi. Riteniamo, infatti, che l’integrazione di set indipendenti di dati raccolti su popolazioni o comunità naturali possa fornire preziose informazioni per evidenziare e stimare l’effetto congiunto di differenti fonti di disturbo sulla componente biotica sensibile di un ecosistema (4), come ad esempio, nel caso studiato, l’osservazione che fenomeni di erosione genetica riflettono in gran parte la frammentazione degli habitat naturali e il disturbo antropico.