Ricerc@Sapienza

A set of Roman orichalcum coins, issued from 88 B.C. to 96 A.D., has been investigated using a multi-analytical approach.The aim of the study is to explore the corrosion processes of this alloy, with a special attention to the dezincification and decuprification phenomena, from the external layers to the unaltered core of the samples.

Zinc oxide (ZnO) nanoparticles were synthesized on diatomite (DE) surface by a low
temperature sol gel technique, starting from zinc acetate dihydrate (Zn(CH3COO)2?·?2H2O)
solution in water/ethyl alcohol, in presence of triethanolamine (TEA) with functions of Zn2+
chelating agent, catalyst and mediator of nanoparticle growth on DE surface. Microstructural
features were investigated by field emission scanning electron microscopy and x-ray diffraction.
ZnO crystalline nanoparticles, well distributed both on the surface and into the porous

The local structure of a series of homologous protic ionic liquids (PILs) is investigated using ab initio computations and ab initio-based molecular dynamics. The purpose of this work is to show that in PILs the network of hydrogen bonds may promote like-charge clustering between anionic species. We correlate the theoretical evidence of this possibility with viscosity experimental data. The homologous series of liquids is obtained by coupling choline with amino acid anions and varying the side chain.

Due to their capability to recover the initial shape, Shape Memory Alloys (SMAs) are widely used in many applications. Different grades are commercially available and they can be classified considering either their chemical compositions (e.g., Cu based, Ni based, Fe based) or according to their mechanical behaviour. The most used SMAs are the Ni based alloys thanks to their performances both in terms of mechanical resistance and in terms of fatigue resistance, but their costs are quite high. Cu based alloys are good competitors of the Ni based alloys.

High?resolution NMR images on three different present?day wood samples and an archaeological wood specimen were presented and discussed. Although the spatial resolution is still low to perform dendrology for the exact identification of the wooden species, the T2?spin?density weighted images exhibit contrasts that are in excellent agreement with optical histological images. On the other hand, T2* and T1?weighted images provide physiological information that is not obtainable by the usual light microscopic investigations.

A bronze axe of the Iron Age found in Motya (Sicily, Italy), in prehistoric strata dating from the 10th century BC (before the foundation of the Phoenician colony), has been characterised using Scanning Electron Microscopy (SEM-EDX), X-ray diffraction (XRD) and Electron Microprobe Analysis (EMPA). The axe was studied using micro-and invasive analyses, aiming to explore microstructure, corrosive process and to acquire quantitative chemical analysis. The results revealed that the axe is composed by a leaded-Cu-Sn alloy.

The aim of this work was to characterize chemical composition of the alloys and corrosion microstructures of Phoenician bronze weapons from the archaeological site of Motya (western Sicily, Italy). For this purpose, some bronze artifacts were selected and studied by the combined use of different analytical techniques, such as scanning electron microscope (SEM-EDS) and electron microprobe analysis (EMPA). Moreover, X-ray maps on cross section of the artifacts were also performed to obtain information about elemental distribution in the different layers.