Il Mausoleo dei Plautii a Tivoli: la diagnostica per la conservazione del travertino

Il Mausoleo dei Plautii, del I secolo d.C., rappresenta un elemento monumentale del più ampio complesso di Ponte Lucano, il simbolo della salita verso Tivoli, che da sempre ha attratto l’interesse degli artisti e dei conoscitori d’arte che in pochi passi raggiungevano l’affascinante sito di Villa Adriana, patrimonio Mondiale dell’Umanità. Oggi il Mausoleo, oltre a trovarsi in una situazione di totale incuria, risulta inserito in un contesto ambientale piuttosto critico, a ridosso cioè del fiume Aniene, e quindi continuamente soggetto ad esondazioni che si estendono fino ad invadere il monumento funerario dove le acque ristagnano anche per la presenza di un muro in cemento di recente costruzione. Al fine di valutare lo stato di conservazione del travertino, materiale costitutivo del sepolcro, e fornire un elemento utile per programmare eventuali interventi di tutela e difesa di questo importante monumento, sono state effettuate alcune indagini diagnostiche tramite prelievi in situ sul Mausoleo e su materiali di cava. Le indagini diagnostiche hanno previsto: esami chimico-mineralogici tramite microscopio polarizzatore, mediante FTIR, μ-FTIR e XRD; analisi morfologica, tramite SEM, di alcune forme di alterazione biologica; test microanalitici per localizzare particolari elementi presenti nel travertino; analisi spettrometrica nel visibile dei sali solubili; prove di imbibizione e di evaporazione

The Painted Silk Panels of Palazzo Barberini at Rome. The Scientific Investigation and Preservation Challenge

AbstractThis paper reports the study carried out on the 18th century painted silk panels that cover the walls of the so called Salotto delle sete dipinte in Palazzo Barberini at Rome on the occasion of the conservation work started in 2007. Microscope and spectroscopy investigations were performed in order to study the materials and the realization techniques of the painted silk panels and to evaluate the conservation conditions. Moreover ageing tests were performed in order to evaluate the stability of the consolidant/protective product used for the silk panels

La valutazione sperimentale dei consolidanti per il legno

The aim of this work has been to test some commercial products as consolidants of the structure of two wooden species: poplar (Populus sp.) and walnut (Juglans regia L.). The chosen products are acrylic, epoxy and aliphatic compounds available in commerce and often employed for other applications. The wooden samples have been prepared according to the UNI ISO instructions. The wood characteristic parameters have been measured: density, basic density, shrinkage, porosity, colour. The wooden samples have been artificial aged by means of frost/thaw cycles. The consolidants have been applied to the wood samples aged and not by means of under vacuum immersion. At the end the wood characteristic parameters and the FTIR spectra have been measured to evaluate the product effectiveness for the wood treatment

Lung hyperaeration assessment by computed tomography: Correction of reconstruction-induced bias

Background: Computed tomography (CT) reconstruction parameters, such as slice thickness and convolution kernel, significantly affect the quantification of hyperaerated parenchyma (VHYPER%). The aim of this study was to investigate the mathematical relation between VHYPER% calculated at different reconstruction settings, in mechanically ventilated and spontaneously breathing patients with different lung pathology. Methods: In this retrospective observational study, CT scans of patients of the intensive care unit and emergency department were collected from two CT scanners and analysed with different kernel-thickness combinations (reconstructions): 1.25 mm soft kernel, 5 mm soft kernel, 5 mm sharp kernel in the first scanner; 2.5 mm slice thickness with a smooth (B41s) and a sharp (B70s) kernel on the second scanner. A quantitative analysis was performed with Maluna® to assess lung aeration compartments as percent of total lung volume. CT variables calculated with different reconstructions were compared in pairs, and their mathematical relationship was analysed by using quadratic and power functions. Results: 43 subjects were included in the present analysis. Image reconstruction parameters influenced all the quantitative CT-derived variables. The most relevant changes occurred in the hyperaerated and normally aerated volume compartments. The application of a power correction formula led to a significant reduction in the bias between VHYPER% estimations (p 0.15 in all cases). Conclusions: Hyperaerated percent volume at different reconstruction settings can be described by a fixed mathematical relationship, independent of lung pathology, ventilation mode, and type of CT scanner

Surface Investigation of Photo-Degraded Wood by Colour Monitoring, Infrared Spectroscopy, and Hyperspectral Imaging

The aim of this investigation is to study the changes occurring on the surface of poplar wood exposed to artificial irradiation in a Solar Box. Colour changes were monitored with a reflectance spectrophotometer. Surface chemical modifications were evaluated by measuring the infrared spectra. Hyperspectral imaging was also applied to study the surface wood changes in the visible-near infrared and the short wave infrared wavelength ranges. The data obtained from the different techniques were compared to find the possible correlations in order to evaluate the applicability of the Hyperspectral imaging to investigate wood modifications in a non-invasive modality. The study of colour changes showed an important variation due to photo-irradiation which is the greatest change occurring within the first 24 hours. Infrared spectroscopy revealed that lignin degrades mainly in the first 48 hours. Concerning Hyperspectral imaging, the spectral features in the visible-near infrared range are mainly linked to the spectral shape, whereas in the short wave infrared cellulose and lignin affect shape and reflectance levels. The proposed approach showed that a correlation can be established between colour variation and wood degradation in the visible-near infrared range; furthermore in the short wave infrared region surface chemical changes can be assessed