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Within the neu_ART project, funded by Regione Piemonte (Italy), a team of specialists in different scientific fields coming from Istituto Nazionale di Fisica Nucleare (INFN), Physics Department of University of Torino and Centro Conservazione e Restauro (CCR) “La Venaria Reale” has developed a new digital X-ray apparatus expressly designed for painted canvas and panels up to about 3 m × 4 m. Compared to all other systems scanning time is faster, the procedure to obtain the whole radiography is easier and images are available in real time. This apparatus has been widely tested on artworks restored at CCR “La Venaria Reale”, allowing to study and optimize the operating parameters and to evaluate its performance, thanks to the feedback provided by professionals involved in the activities of conservation. Supported by the results presented in this work, restorers had the possibility to investigate the materials characteristics and to plan the operating strategy in advance: indeed, radiographs revealed areas with losses of paint, repainted areas, canvas damages, hidden pictures, writings and previous restorations. The X-Ray system for Digital Radiography is integrated in a more complex apparatus that can be used also for computed tomography of voluminous objects up to 2.5 m in height and 2 m in width, making the apparatus developed in the neu_ART project a unique and comprehensive tool at conservators' disposal.

We present x-ray imaging results for diverse iron-based-ink antique writings - single-page manuscripts, stacks and scrolls - from the 16th century on. The objective is to elaborate new digitization techniques by x-ray tomography for the “Venice Time Machine” (VTM) project in collaboration with the “Archivio di Stato”. The technique can potentially read unopened - perhaps unopenable - documents and speed up the entire digitization process of large collections. The technique is feasible thanks to the highly absorbing chemical elements in ancient European ink recipes. The corresponding x-ray contrast allows character reading with reasonably short exposure times. The impact is quite relevant: the potential feasibility of “softer” and faster digitization of huge collections like the Archivio di Stato - 80 km of documents spanning 10 centuries.

Hydrogen sensors, intending to operate at low temperatures (around 25°C), based on TiO 2 nanotube arrays were fabricated and characterized in N 2 /H 2 atmosphere with different nitrogen concentrations. The nanotube arrays were obtained through Ti anodic oxidation in a NH 4 F in ethylene glycol (0, 5 % in weight) and 2 % H 2 O bath, magnetically stirred at room temperature. The TiO 2 nanotube hydrogen sensors were characterized at room temperature with hydrogen concentration varying from 50 to 4000 ppm. A linear conductance variation between 50 and 500 ppm was observed. This result is very attractive for hydrogen sensors where low operation temperatures are needed, for example, in medical applications.

TiO 2 nanotube arrays obtained by Ti foil anodization are tested as pH electrodes, showing performance close to standard glass electrodes. The TiO 2 nanotube arrays were obtained by Ti foil anodization in a NH 4 F organic solution with 20, 40 and 60 V and different anodization times. The obtained nanotubes samples were characterized by Scanning Electron Microscopy (SEM). Electrode modified by TiO 2 nanotubes were characterized in pH buffer solution (pH of 4.0, 7.0 and 10.0) and the obtained results show that electrode modified by NTs obtained with anodization voltage of 40 V with 45 minutes presents an almost linear response close to Nernst equation (59 mV/pH).

The development of high sensitive miniaturized sensors is of special importance for “Lab on a Chip” and biosensors development [1]. In this context and due to its n-type semiconductor character and its high chemical stability, TiO 2 thin films have been proposed for application as pH and H sensors [2]. Even more, taking advantage of their high specific surface, TiO 2 nanotubes have been also considered as a natural candidate for application in pH detection [3].