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The study and characterization of an art work carried out by two or more artists is always an interesting challenge since each painter, although belonging to the same artistic current, can introduce specific pictorial materials or peculiar aesthetic effects, which constitute the artist fingerprint. This work presents a preliminary analytical study of the “Portrait of Mario Nuzzi”, painted by Giovanni Maria Morandi and Mario Nuzzi. In particular, non-invasive investigations were conducted using UV–VIS–NIR–SWIR multispectral imaging, radiography and X-ray spectroscopy (XRF). Multivariate analyses (PCA) were performed on VIS–NIR multispectral imaging in order to highlight some details not clearly visible using a traditional univariate analysis. Such an approach could be useful for authentication processes. In particular, in this paper we propose the use of the score density plot to determine the artist’s “chiaroscuro” fingerprint. Finally, the artist’s palette was compared with that of the “Primavera” painting, painted by Mario Nuzzi and Filippo Lauri, by using XRF analyses. We discovered that “Portrait of Mario Nuzzi” has not been significantly changed since the final version. Furthermore, the elemental composition of the pigments revealed that the palette used in the two paintings does not completely overlap. This aspect encourages us to perform a more detailed analysis of the pigments with the aim of better discriminating the parts painted by Mario Nuzzi from those of each collaborator.

We have used time resolved small angle X-ray scattering (SAXS) for investigating the early stages of the formation of crystalline colloidal Ag particles by AgNO3 reduction with ascorbic acid in an aqueous acidic solution of a polynaphthalene sulphonate polymer (Daxad). In order to exploit the polymer role in silver crystallization, the measurements have been performed at different polymer concentrations. Data analysis suggests that the nucleation and growth of primary particles of about 20 nm in diameter, occurring in a surface-fractal arrangement of the dynamic polymeric template, is assisted by the development of long range spatial correlations. These correlations could be a sign of polymer-induced liquid fluctuations as intermediate precursors of Ag crystallization.

Grazing incidence synchrotron X-ray diffraction was used to investigate the structure of vacuum-sublimated tetracene thin films (6–50 nm thick) deposited on silicon dioxide. The films were found to be polycrystalline with crystallite texturing and size increasing with the deposition flux. This last parameter was found to have a great influence on the relative amounts of the polymorphs (thin film α and β phases) composing the films. These two different phases are characterised by different spacings of the (0 0 l) planes, the spacing of the α phase being closer to that of the bulk. The thicknesses of the two phases in the film change as a function of the deposition flux. Finally, we discuss the role of the deposition flux on the charge-carrier mobility in tetracene films used as active layers in field-effect devices.

FELs based on SASE are believed to be powerful tools to explore the frontiers of basic sciences, from physics to chemistry to biology. Intense R&D programs have started in the USA and Europe in order to understand the SASE physics and to prove the feasibility of these sources. The allocation of considerable resources in the Italian National Research Plan (PNR) brought about the formation of a CNR–ENEA–INFN–University of Roma “Tor Vergata” study group. A conceptual design study has been developed and possible schemes for linac sources have been investigated, leading to the SPARX proposal. We report in this paper the results of a preliminary start to end simulation concerning one option we are considering based on an S-band normal conducting linac with high-brightness photoinjector integrated in an RF compressor.

A new beamline for macromolecular crystallography has been constructed and is currently under commissioning. Its source is the high-power wiggler at the 2 GeV storage ring ELETTRA. The optics consists of a double-crystal monochromator in nondispersive configuration followed by a toroidal focusing mirror, and is designed to allow both diffraction experiments with monochromatized beam in the energy range 4-25 keV, and Laue experiments with white beam. The experimental station is based on an imaging plate area detector from MarResearch and a model 5020 Huber 4-circle diffractometer. To control the second apparatus, a plug-in board interface for a personal computer and a crystallographic package, CS, have been developed.