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ABSTRACT Nano-sized Ti[O.sub.2] is widely used as photocatalysts for many applications; however, some aspects in the application in cultural heritage conservation are still unresolved. In particular, in this research, we [...]

Background and Objectives: Being highly consumed by the population for nutritional purposes, the monitoring of radionuclides in milk represents a very important task for the protection of human health. The present paper reports the results of an investigation aimed at determining the natural and anthropogenic radioactivity content in milk and assessing the radiological health risks due to its ingestion. Methods: Liquid for infants, Ultra Heat Treated (UHT) sheep, UHT cow, and UHT goat milk samples, coming from Italian large retailers, were investigated. In particular, a total of twenty samples, five for each type, were analyzed by using High Purity Germanium (HPGe) gamma-ray spectrometry, with the ultimate goal of quantifying the specific activity of natural and anthropic radionuclides (4400K and 137Cs, respectively). The evaluation of dose levels due to the milk ingestion was also performed for six age categories, namely infants, 1-5, 5-10, 10-15, 15-17 years old, and adults (> 17 years old), taking into account the average yearly direct consumption in Italy and under the a priori hypothesis that this need can be satisfied by a single variety of milk. Results: The mean specific activity of 40K varies from (30 ± 4) Bq L-1 to (48 ± 6) Bq L-1; the lowest value was obtained for the UHT sheep milk, while the highest one for the UHT cow milk, with investigated Italian large retailers milk samples presenting an activity concentration of (38 ± 5) Bq L-1 on average. The 137Cs specific activity is lower than the minimum detectable activity (MDA) value for all investigated samples. Regarding the dose levels due to the milk ingestion, the obtained values remain below the threshold value of 1 mSv y-1 set by the Italian legislation. Conclusion: Reported results then show that the radiation dose incurred from the ingestion of the investigated milk samples poses no significant health effect on the population from a radiological point of view.

In this paper, we analyze the internal picosecond dynamics of enantiomeric ((S)-) and racemic ((R, S)-) ibuprofen (IBP), when forming inclusion complexes, in solid state, with methyl-β-cyclodextrin (Me-β-CD), by inelastic and quasi elastic neutron scattering. The study was aimed at understanding, by the analysis of the vibrational and relaxational properties of the inclusion complexes also with respect to the single components, if and how the differences in the structural properties of the hydrogen bond (HB) network of (S)- and (R, S)-IBP can have influence on the complexation process triggered by “host-guest” interactions, whose detailed knowledge is retained a prerequisite for enantiodiscrimination. From the results, a similar complexation mechanism for (S)- and (R, S)-IBP is argued, with a preferred penetration mode involving the isopropyl group of IBP.

The present work reports a multi-analytical study, based on Polarized Optical Microscopy (POM), Scanning Electron Microscopy equipped with an Energy Dispersive X-ray detector (SEM-EDX), micro-Raman and Fourier Transform Infrared Spectroscopy (FT-IR) techniques, aimed at establishing the painting techniques and palettes used to decorate a variety of fragments of frescoes coming from Villa dei Quintili in Rome (Italy) and dated back 2nd century CE. This combined methodological approach, covering different spatial scales extending from the macroscopic to the elemental domain, revealed successful for the unambiguous identification and characterization, in non-invasive or at least micro-destructive way, of pigments, binders and stone materials. The used chromatic palette was identified as yellow ochre (goethite), carbon black (vegetal origin), probably green earth and Cu-green pigment, red ochre (haematite), lime white and Egyptian blue (cuprorivaite). Organic and inorganic binders were respectively identified as linseed oil and lime, this latter carbonated to calcium carbonate. Textural features of plasters were also evaluated in order to investigate raw materials used for their production.

ABSTRACTIntroduction:In light of the recent development of new soft materials, nanostructured self-assembled systems have attracted attention in a variety of technological fields of high social impact. Cyclodextrin nanosponges (CDNS) represent a new and highly versatile class of cross-linked cyclodextrin (CD)-based nanoporous polymers. Their intriguing properties, including safety, biodegradability, negligible toxicity, marked swelling behavior, superior inclusion capability with respect to native CD, are the bases for potential for applications in drug delivery, tissue engineering and regenerative medicine.Areas covered:We report on the state-of-art concerning a detailed characterization of structural and dynamical features of CDNS explored by the combined use of different and complementary techniques, such as Fourier transform infrared absorption in attenuated total reflectance geometry (FTIR-ATR) and Raman spectroscopies, and high resolution magic angle spinning (HR-MAS) NMR spectroscopy. The ambitious objective is to furnish an exhaustive survey of the role played by hydrophobic and hydrophilic groups within the cross-linked network, in dry and swollen states, in determining the macroscopic functional features of CDNS.Expert opinion:The reported results may significantly contribute in the rational design and optimization of new stimuli-responsive systems exhibiting tunable inclusion/release properties, adapted to the therapeutic demands of pathology.

The complete knowledge of the porous structure of rocks is necessarily requested for the prediction of the damages induced by salt crystallization. Nevertheless, the geometric description of the porous structure is usually very difficult because of the variability of the size distribution of voids, ranging from nanometers to millimeters, which generally is not accessible by a single methodology. For this reason, a multi-technique approach was used here: the investigation at sub-micrometric dimensional scale (> 0.004 µm) was carried out by Hg intrusion porosimetry (MIP), whereas the study at the nanoscale required Small Angle Neutron Scattering (SANS) analysis. All the results were interpreted in the framework of a fractal model. The analyses were performed on limestones of different geological formations, cropping out in south-eastern Sicily and largely used as building stones in Baroque monuments of the Noto Valley (belonging to the UNESCO Heritage List).

In the present study, an innovative methodological approach has been proposed in order to characterize meteoritic samples without removing or causing damage to any part of them. In particular, Raman and X-ray fluorescence (XRF) measurements have been preliminarily performed, using portable instruments, in order to obtain qualitative and semi-quantitative compositional information, respectively. These analyses have been followed and supported by time of flight neutron diffraction (TOF-ND) experiments, which allowed us to perform quantitative mineralogical phase analysis. Such a methodological approach was tested on four meteoritic samples, of different types and sizes, coming from several different regions of the Solar System (e.g., the Moon, Mars and asteroids). The validity and strength of the results obtained using these techniques are discussed and compared with results available in the literature.

Detailed spectroscopic studies performed by quasi-elastic and inelastic light scattering (Rayleigh wing and Raman) and a preliminary analysis by quasi-elastic and inelastic neutron scattering (incoherent quasi-elastic neutron scattering (IQENS) and incoherent inelastic neutron scattering (IINS)) in water, in the bulk and in confined geometry at different hydration levels and at room temperature, are presented. The possibility to compare the experimental results obtained by both the complementary spectroscopic techniques and analysed in the framework of existing models for confined liquids, has allowed us to identify the clear influence of the confinement on the mobility of this fundamental liquid, which shows a dramatic frozen-in effect with respect to the bulk state. In addition, the presence of an α-relaxation process, related to a distribution of relaxational times which recalls the mode coupling theory (MCT), characteristic of dense supercooled liquids, has been confirmed. Furthermore inelastic features in both spectroscopies show a loss of low frequency collective vibrational bands connected with the presence of tetrahedral environments for physisorbed water. Finally Raman results show a systematic lowering of the OH stretching bands for water involved in tetrahedral C_2v symmetry.

Tituli Pictiare an ancient form of urban graffiti very common in the archaeological site of Pompeii (Naples, South—Italy). They are generally made of red pigments applied on walls of Campanian ignimbrite. This paper deals with a scientific investigation aimed to their conservation. This is a challenging task since it requires a multidisciplinary approach that includes restorers, archaeologists and conservation scientists. The study has provided suggestions on the proper way to conserve Tituli Pictiover time. In the present work, several specimens of Campanian ignimbrite were painted with red earth pigment; lime and Arabic gum have been used as binders as well. Such painted stones were treated with three consolidants: a suspension of reactive nanoparticles of silica, ethyl silicate and an acrylic microemulsion. Treated and untreated specimens were subjected to thermal aging, artificial solar radiation and induced crystallization decay. It has been assessed the colorimetric variations induced by treatments. Moreover, the micromorphologic features of the consolidated surfaces have been highlighted by means of electron microscope observations. The scotch tape test allowed to compare the superficial cohesion induced by the three used products. According to the results, ethyl silicate seems to represent the most successful product.

We provide an overview of recent results obtained by the innovative application of mobile spectroscopy for in situ investigation in archaeometry. Its growing relevance is linked to the great advantages of avoiding the transport and eventual damage of precious artifacts and of allowing the analysis of those specimens that are, for example, built into infrastructures or in some way permanently affixed. In this context, some case studies of combined instrumental approaches, involving X-ray fluorescence (XRF) and Raman spectroscopy, integrated by infrared thermography (IRT), are, in particular, discussed: the archaeological site of Scifì (Forza d’Agrò, province of Messina, Italy) and the Abbey of SS. Pietro e Paolo d’Agrò (Casalvecchio Siculo, province of Messina, Italy). In the first case, the elemental composition, as obtained by XRF, of two types of mortars belonging to two different chronological phases, dated back between the 3rd and the 5th century AD, allowed us to hypothesize a same origin area of their raw materials and a different production technique. Again, the combined use of XRF and Raman spectroscopies, supported by IRT technique, on pottery fragments of Greek-Hellenistic age and late imperial period, furnished important information concerning the receipts for the pigmenting agents of the finishing layer, allowing in some cases their unambiguous identification. In the second case, XRF data collected on bricks and stones from the external facade of the abbey allowed us to make some hypothesis concerning the provenance of their constituents materials, supposed to be in the area of valley of the river Agrò.