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La successione tardo messiniana di Fonte dei Pulcini (FPA) (Maiella sud-orientale), deposta in un bacino di avampaese, ha registrato numerose variazioni paleoambientali in termini di paleoprofondità, paleosalinità, apporto detritico, evaporazione/precipitazione e aridità/umidità. Queste variazioni paleoambientali sono state messe in evidenza attraverso l’analisi integrata di dati paleontologici, geochimici e mineralogici. L’analisi della suscettività magnetica nella successione di FPA ha permesso di effettuare una calibrazione astrocronologica delle variazioni paleoambientali e paleoclimatiche, vincolando la sezione tra 5,394 e 5,335 Ma. Confrontando la curva dell’insolazione con le variazioni paleoambientali registrate dalla sezione FPA è stato messo in evidenza un ritardo di 5-8 ka tra la causa astronomica della variazione climatica e la risposta del bacino sedimentario.

L’analisi mineralogica semiquantitativa di campioni di suolo ricchi in componente argillosa consente di ricavare stime dell’abbondanza percentuale dei minerali argillosi presenti. Non deve essere considerata come un mezzo per determinare le quantità assolute di minerali in un determinato campione, quanto piuttosto, un “ottimo” metodo per monitorare le variazioni quantitative degli stessi minerali in sequenze di campioni.E’ opportuno evitare che il campione venga sottoposto a trattamenti invasivi come attacco acido, macinazione spinta, sonicazione e uso di disperdenti che potrebbero modificare la composizione e/o la struttura dei minerali e quindi alterare il tracciato diffrattometrico. L’analisi semiquantitativa viene generalmente eseguita sul tracciato diffrattometrico della frazione granulometrica

This paper provides new geochemical, petrographic, and isotopic data over a set of 39 samples representative of all different units present in the quaternary volcanism of Monti Cimini region (Provincia Magmatica Toscana) and Vico volcano (Provincia Magmatica Romana). Monte Cimini volcanics are older in age (around 0.94 Ma) includes trachytic and latitic rocks with isotopic ratios 87Sr/86Sr 0.713413„b14 a 0.715685„b5, and 143Nd/144Nd 0.512053„b3 to 0.5121339„b3. Vico volcano (0.4 Ma) products range between phonolitic and trachyandesitic compositions and shows 87Sr/86Sr values of 0.710923„b5 a 0.711264„b6 and 143Nd/144Nd 0.512092„b3 to 0.512122„b3. All these new data are in good agreement with their former attribution to the aforementioned magmatic provinces.

Two bronze sculptures, Ettore e Andromaca, a reproduction of a plaster model by Giorgio de Chirico, and Cardinale, a cast made from an original by Giacomo Manzù, stand outside the Carlo Bilotti contemporary art museum in Villa Borghese park (Rome). The composition of the artificial brown patina present on the statues’ surface, which was applied for aesthetic purposes, is unknown. This paper reports analysis carried out to identify the composition of the artificial patina and describe the corrosion products formed in outdoor conditions. Raman spectroscopy and scanning electron microscopy equipped with X-ray microanalysis were performed on sample fragments and powder scrapings taken from the bronze statues. X-ray powder diffraction was used whenever possible and subject to conservation priorities. Our data revealed, in the artificial brown patina, the formation of copper oxides (cuprite and tenorite) on the surface of both sculptures as possible result of oxidisation treatments performed with a blowtorch before the artificial patination process began. Furthermore, a copper nitrate (gerhardtite) was identified as an ingredient in the preparation applied to the bronze surfaces. The green areas revealed the presence of corrosion products as copper sulphate hydroxide (brochantite) and copper sulphate-chloride (connellite), which form under acid rains conditions.

Seventeen different colored fragments from six selected pre-Columbian estucado ceramics from El Salvador have been investigated by Raman spectroscopy, scanning electron microscope coupled to an energy dispersive spectrometer (SEM/EDS) and X-ray powder diffraction (XRPD). The peculiarity of this kind of ceramics consist of the unusual presence of a white engobe, traditionally termed stucco, between the ceramic body and the decoration elements, hence the name estucado ceramics. The aim of this work was to study the unusual manufacturing technique and to identify the chemical composition of the engobe and of the pigment palette. The results showed that the stucco layer is made of clay (kaolinite) with traces of titanium oxide (anatase). Remarkably, this is the same composition of the white pigments used for the decoration layer, thus excluding an early use of natural titanium oxide as a white pigment in the estucado productions as suggested in previous investigations. Moreover, the presence of kaolinite and anatase both in the stucco and in the decoration layer suggests a cold-working or low temperature technique. The red, yellow and green decorations were realized by the use of natural ochre, while in all the blue and gray decorations Maya blue pigment was identified. Finally, an amorphous carbon pigment of vegetal origin and manganese oxide were used to obtain black pigments.

The catalytic performances of Ni/CeO2–Al2O3 catalysts for the dry reforming of CH4 (DRM) were investigated. Catalysts with different Ni dispersion and different amount of CeAlO3 species were prepared by different methods and characterized by BET, XRD, XPS, Raman, TPR and TPO techniques. Catalytic activity was studied during time on stream in the range 873–1073 K with a mixture of CH4:CO2:Ar = 40:40:20 vol.% and GHSV 90,000 cm3 g−1 h−1. The intrinsic catalytic activity increased with the increasing of Ni crystallite size. Carbon was deposited as nano-fibres and graphite when catalysts worked at lower temperature, and the largest amount was found on the catalyst with the largest Ni crystallite size. The formation of graphitic deposits is limited by the presence of CeAlO3 species formed during catalyst activation. CA preparation method results particularly attractive because it allows to obtain catalysts with small Ni crystallite size and high content of CeAlO3 species, which both have a role in suppressing the carbon deposition and therefore in obtaining stable catalytic performances.