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In this paper an overview of recent applications of mid-wave infrared imaging techniques to the study of books is presented. Studies performed by thermography and mid-wave infrared reflectography a...

The study of bronze statues obtained by the lost-wax casting method results of particular relevance from the artistic and historical points of view. In particular, the characterization of structural and subsurface elements of bronzes is very useful to gather insight concerning their preservation state and manufacturing process. For these purposes, infrared thermography has been successfully employed to investigate different kind of items of artistic bronzes, such as repairs, defects and inserts, providing also the possibility to perform the depth-resolved study of the observed subsurface features thanks to the possibility it also provides to evaluate the thermal transport properties of the investigated materials. In this work, the experimental configurations and the capabilities of such a technique have been reviewed. The state of the art of the results obtained by infrared thermography for the analysis of artistic bronzes is presented. It is thus shown that infrared thermography can be nowadays considered as a reliable and consolidated technique to map in a non-destructive way a wide spectrum of features of bronzes.

A study of phase transitions of photochromic p,p’-n-alkylazobenzenes compounds was carried out by means of adiabatic scanning calorimetry (ASC) and photopyroelectric calorimetry (PPE) techniques, yielding accurately the temperature dependence of the enthalpy and of the specific heat capacity across the observed phase transitions, and the corresponding enthalpy of transition values. In addition, polarization microscopy imaging of the sample texture was performed together with the PPE calorimetric evaluations to establish the nature of the involved phases. By performing PPE calorimetric evaluations during UV irradiation of the samples, the influence of the photoinduced trans to cis isomerization of the nAB molecules on the occurrence of the phase transitions was assessed.

Library material, and thus parchment, is frequently subjected to bio-deterioration processes caused by microorganisms. Fungi and bacteria cause alterations in the parchment inducing, in some cases, even the partial detachments of the surface layer and the loss of any text present on it. An important contribution to disinfection of the cultural heritage artefacts is given by the use of ionizing radiation. In this work, a preliminary study on the applicability of X-ray radiation as treatment for bio-deterioration removal is proposed. The results on the microbial growth after different irradiation treatments are shown in order to detect the dose protocol for the bio-degradation removal. Furthermore, the evaluation of the irradiation effects on the parchment microstructure is presented in order to define the applicability of the method on parchment artefacts.

© 2019 Elsevier B.V. The collagen denaturation process in several artificially aged modern parchment samples were studied by combining Adiabatic Scanning Calorimetry and Light Transmission Analysis investigations. It was found that the calorimetric evaluations enabled not only to confirm the previously reported specific heat results concerning the collagen denaturation peaks, but also to identify a novel broad feature most likely associated with additional transformations occurring once denaturation takes place. Moreover, the combination of the investigations by the two adopted techniques allowed to validate the Light Transmission Analysis as a novel simple method capable of recording the entire collagen denaturation temperature path of the analyzed samples. Finally, the polarization microscopy imaging, performed simultaneously with the optical transmission characterization, enabled to perform a direct correlation of the morphology changes of the parchment with the different stages of the collagen denaturation. ispartof: Thermochimica Acta vol:676 pages:263-270 status: published

In this paper a thermographic study of the Boxer at Rest and so called “Hellenistic Prince” archaeological bronzes aimed at obtaining a comparative analysis of the structural and the surface features between the two is presented. In particular, infrared thermography has been employed to characterize the Boxer's inlaid inserts and also to assess the presence of similar inserted items in the “Prince”. Moreover, other features of interest, such as defects and repairs, are analysed in order to gather additional information about the investigated bronze statues and, also, to point out possible differences/similarities in their structure and, in particular, in the bronze surface finishing.

In this work, we report on the application of Pulsed Infrared Thermography for the analysis of the thermal diffusivity dependence on the composition of copper alloys with a tin (Sn) and lead (Pb) concentration typical of ancient bronze artefacts. To this aim, specifically prepared bronzes samples have been investigated. Both the measured thermal diffusivity values and those retrieved from the literature showed a decreasing trend with increasing Sn and Pb concentration. In the overall data analysis, the concentration of Pb atoms was weighted by a coefficient to account for their lower efficiency in reducing the thermal transport properties of the alloy with respect to the Sn atoms. Electrical conductivity values measured on the same samples showed a dependence very similar to that obtained for the thermal conductivity, pointing out the mainly electronic nature of the thermal conductivity in such samples.

Pulsed thermography has proven to be a useful tool to detect subsurface features in ancient bookbindings and, in particular, to provide the IR image of texts buried beneath the end - leaves of the books. In this paper the theory is presented to analyze the influence of the geometrical and physical parameters involved in the processes leading to the distortion in the IR image of the detected buried graphical features. The distortion is mainly due to the lateral diffusion of the heat generated at the ink feature after the absorption of an excitation light. A comprehensive analysis taking into account the three dimensional heat diffusion process, in an optically semi-transparent medium, is considered. Numerical results are reported showing the behavior of the contrast and of a distortion parameter of the buried inked feature detected by the IR imaging in the various considered cases.

In the analysis of complex stratigraphical structures like painted artefact, infrared (IR) techniques can provide precious information about elements hidden under superficial layers of the artwork, such as pictorial features and structural defects. This paper presents a novel complementary use of reflectographic and thermographic techniques for the survey of three baroque paintings, preserved at the Chigi Palace in Ariccia (Italy). First, the IR-ITR laser scanner prototype has been used for the preliminary and remote near-IR reflectographic survey of the areas where the canvas was located. The resulting map was then used for planning the thermographic and mid-IR reflectographic studies, focusing the analyses on the most interesting areas of one of the paintings, called “La Primavera”. The combination of the three imaging techniques revealed several details not visible by the naked eye, such as restored lacunas and pentimenti, demonstrating the validity and complementarity of the proposed combined methodologies.

Active pulsed infrared thermography is an effective technique consisting in moderately heating the specimen by means of the absorption of a visible light pulse and, then, in detecting the transient variation in the emitted infrared radiation by an infrared camera. Inhomogeneities and buried features eventually located into the specimen volume can be revealed by the recorded infrared images. Such a technique has been successfully applied to the analysis of cultural heritage artifacts like ancient bronzes and manuscripts. The former belong to the category of optically opaque materials, whereas the second to the one of optically semi-transparent materials. For both the two considered categories, a mathematical model for the analysis of the thermographic signal is here presented, together with an implementation in Matlab environment using the finite element technique. The developed models are then used to analyse the experimental results and, hence, to obtain both qualitative and quantitative information about the investigated items.

In library heritage, the practice of reusing fragments of older manuscripts was very common, providing complex structures characterised by several overlapped features. Pulsed Thermography enables non-destructive investigations of such a stratigraphic structure and the detection of hidden texts. In this work, a study of the contrast generation in their thermographic detection is presented, aimed to the evaluation of the edges distortion for enhancing the readability of such features which is crucial for palaeographic purposes.

Bowed string instruments represent a peculiar class of artworks, in some cases of historical relevance, capable of producing sound. Concert activity and natural ageing could cause mechanical stress that may lead to defects and fractures. Here, we propose an image-based methodology suitable to investigate such structural features in wooden instruments. The combined use of X-ray radiography and infrared thermography enabled a better identification and documentation of defects, woodworm galleries and cracks, thus enhancing the commonly employed approach.

In this work, the capability of Infrared Thermography to characterize in a non-destructive way the main features of illuminated manuscripts has been assessed. It has been shown how this technique can be exploited for a general investigation of the book materials, structure and decorative apparatus, providing information on the manufacturing method, the preservation state and the changes operated throughout the history of the artefact. The used thermographic approach provided infrared images which show also the non-visible surface and subsurface elements that constitute the illumination metastructure, intended as the structure of the entire pictorial system. A number of aspects, like the verification of the adhesion state of the gold leaf, the recovery of the pentimenti, the detection of metal foil residues and the characterization of the damage produced by fungi and bacteria have been studied. For each of the investigated features an interpretative model accounting for the infrared emission processes responsible of the thermogram generation has been proposed. Moreover, for every studied aspect, it has been shown how, based on the thermographic results, other complementary analyses can be directed like Infrared Reflectography, Scanning Electron Microscopy, X-ray Fluorescence and the Energy Dispersion Spectroscopy. The effectiveness of the proposed approach has been tested in the study of Liber Regulae S. Spiritus de Saxia, a 14th century illuminated manuscript of great historical importance and artistic value, since the wide spectrum of the employed materials and the complexity of the structural changes operated during its history by extensive restoration make it a valid test-bed.

In this paper a method is presented based on the use of active infrared thermography for the detection of subsurface graphical features in artworks. A theoretical model for the thermographic signal describing the physical mechanisms which allow the identification of the buried features has been proposed and thereafter it has been applied to the analysis of the results obtained on specifically made test samples. It is shown that the proposed model predictions adequately describe the experimental results obtained on the test samples. A comparative analysis between the proposed technique and infrared reflectography is also presented. The comparison shows that active thermography can be more effective in the detection of features buried below infrared translucent layers and, in addition, that it can provide information about the depth of the detected features, particularly in highly IR diffusing materials.

Over the last few years, there has been an increasing interest in the application of photothermal techniques to the investigation of cultural heritage. Thanks to their peculiar ability of depth-resolving the position of subsurface features, these techniques are in fact well suited for a nondestructive analysis of multi-layer structures such as the one typical of artwork. In addition, the recent availability of highly developed instrumentation makes it possible to effectively carry out in situ investigations into different kinds of artwork. Such circumstances have created new opportunities in both theoretical and experimental research whose development is still in progress. In this work, we report an overview of the results that have been obtained on several kinds of artwork and of further developments that can be used to improve the effectiveness of the application of photothermal techniques to this field.

In this work, an experimental method based on the use of pulsed thermography is proposed for the depth-resolved characterization of double-layered structures of cultural heritage items. A quantitative evaluation of the inspected features was achieved by comparing thermographic data with theoretical predictions provided by specifically developed theoretical models for the analysis of the thermographic signal. In this respect, thermographic models for both optically opaque and semi-transparent materials were employed to analyze the results obtained in copper alloys and paper-based original artworks, respectively. Thermographic inspections aimed at establishing the procedure adopted for the application of insertions in ancient bronze statues are presented. Finally, the evaluation of the depth position of graphical features buried beneath leaves of historical books is proposed.

In this paper, infrared thermography is applied to the quantitative characterization of optically semi-transparent media by using a newly introduced mathematical model. The method is specifically aimed to the detection and evaluations in graphic features buried beneath the surface of some particular kind of cultural heritage artefacts, such as books and documents. A numerical approach based on the finite element method, is proposed for solving the model equations. The computed thermographic signal depends on different inspected material physical properties, which have been selectively evaluated by comparing the theoretical results with the experimental ones in specifically designed test samples. Thereafter, the model is applied to the analysis of the results obtained in the case of graphic elements buried within samples constituted by the same previously characterized materials.

The application of science and technology to the knowledge and protection of cultural heritage can help the experts in conservation of historical assets to develop new strategies.A multidisciplinary approach makes to tackle the issues of evaluation, restoration, use and enhancement in a more mature way. Physics and biology sciences applied to the care and diagnosis of cultural heritage is an innovative research field capable of giving unreleased answers to problems still open.As part of the activities undertaken in collaboration between the nuclear fusion technologies and safety department of the ENEA Frascati research center and the Mathematics, Physics and Natural Sciences Faculty of the University of Rome Tor Vergata, an innovative approach has been developed to the study and handling of library goods in general and parchment supports in particular.The aim of our work has been to demonstrate the applicability of bio-degradation removal treatments through ionizing radiation in a non-invasive and safe way and to the characterize the material from the microbiological and opto-thermal point of view.

In this paper, a new method based on the use of infrared thermography is proposed for the characterization of repairs and inserted parts on ancient bronzes. In particular, the quality of the contact between different kind of insertions and the main body of bronze statues is investigated by analysing the heat conduction process occurring across the interface between them. The thermographic results have been used to establish the nature of these inserted elements and the way they have been coupled to the main body of the statue during and after the manufacturing process. A model for the heat conduction based on the numerical finite elements method has been applied to compare the obtained results to the theoretical predictions. Measurements have been first carried out on test samples and then in the field on the Boxer at Rest (Museo Nazionale Romano in Rome), a masterpiece of the Greek Statuary, which contains a large variety of inserted items and repairs which are typical of the manufacturing process of bronze artefacts in general.

In this paper, the thermographic results obtained by studying some masterpieces of the bronze statuary of Rome are presented. More specifically, a quantitative approach has been adopted in the investigation of the Capitoline She Wolf, hosted in the Musei Capitolini, and of the Boxer at Rest and the Hellenistic Prince belonging to the collection of the Museo Nazionale Romano. The obtained results provided data useful to characterize the properties of the bronze alloy and several subsurface features of the statue, such as casting faults and patches. In particular, the interface between different kind of patches and the main body of the statue has been investigated in order to determine the way they were applied. Moreover, the thermal diffusivity of the alloy of the Capitoline She Wolf has been evaluated and quantitative investigations have been carried out in order to determine the depth of some features, such as the cavities originating from air bubbles in the casting melt.

Pulsed infrared thermography was applied to the analysis of the Capitoline She Wolf bronze statue, in the collection of the Musei Capitolini in Rome. We show how it can be used to study the bronze alloy properties and several subsurface and structural features of the statue such as casting faults and repairs providing information useful to recover the steps of the manufacturing process. In particular, the thermal diffusivity of the alloy was determined and quantitative evaluations were carried out concerning the thickness of the bronze in various parts of the statue, the depth of cavities originating from air bubbles in the casting melt and the profile of the contact area of some patches applied to mend gaps left after the casting process. Finally the obtained thermal diffusivity value was discussed in relation to the actual bronze composition of the She Wolf statue and it was shown to be consistent with the trend of values expected for different copper alloy compositions.

Active infrared thermography is an important non-destructive technique frequently employed in the analysis of cultural heritage. For its capability to show subsurface features in the artifacts, this technique has been used to investigate various kinds of artifacts, composed of different structures and materials. In this work, an overview of its recent applications is presented. In particular, the detection of cold working features in bronze sculpture investigations, of buried features in ancient book bindings, such as their structural characteristics and written scraps re-used in their manufacturing process, and on the investigation of defects and inhomogeneities in illuminations, is reported.

The infrared (IR) emissivity of a set of polymeric fibers composed of randomly oriented carbon nanotubes dispersed into a poly(ethylene terephthalate) matrix host was investigated. Samples containing different amounts of carbon nanotubes in the range between 1 and 10 wt% were analyzed. The effects of the included carbon nanotubes on electrical and morphological properties were studied by means of electric conductance, scanning electron micrography and white light interferometry investigations, respectively. The emissivity was characterized in the 3.5–5.1 μm spectral range by using the infrared thermography technique under heating regime. To analyze the obtained results, a theoretical model based on the Maxwell Garnett theory has been proposed. A percolation effect in the electrical conductance and a gradual increase of the emissivity has been observed, respectively with increasing carbon nanotubes content. In particular, morphological investigations showed the emerging surface roughness when carbon nanotubes are added to the polymeric matrix which may further contribute to the increase of the emissivity value. On the basis of the obtained results, it can be concluded that the investigated composite fibers have the potential to develop new materials enabling both high IR emission and large electrical conduction.

In this work we investigate various aspects of the finishing process in ancient bronze sculptures by means of active infrared thermography (IRT). Active IRT provides information on surface and sub-surface features of the investigated artefact, by analysing the heat diffusion process induced within the sample by appropriate thermal stimulations usually produced by absorption of light emitted by different sources. The aim of this research is, in particular, to investigate the processing of bronze surfaces, revealing repairs like plugs, fillings, local castings and concealed marks.

In this paper, an overview of the recent applications of pulsed infrared thermography is presented. Pulsed infrared thermography, which provides stratigraphic information by analyzing the heat diffusion process within the sample after a thermal perturbation, is applied to the investigation of different kinds of cultural heritage artefacts. In particular, it is used to analyze repairs, decorative elements, and casting faults on bronzes, to detect texts hidden or damaged in ancient books/documents, and to characterize paint decorations. Moreover, the integration of pulsed infrared thermography and three-dimensional shape recording methods is proposed in order to provide a three-dimensional representation of the thermographic results. Finally, it is shown how the obtained thermographic results may be crucial from the historical and artistic points of view for understanding the modus operandi of a specific artist and/or of a workshop and for reconstructing the manufacturing process of the analyzed artefacts.

In this work, active infrared thermography was applied to study a seventeenth-century painting on paper, namely the Chigi's family tree, housed at Palazzo Chigi in Ariccia (Rome). Thermography was performed before and after restoration to obtain information used in planning the restoration and also to assess its effectiveness. Infrared thermography provided important information on the artifact structure, areas of damage, structural defects, and the state of adhesion between different layers of the composite artifact before and after the treatment.

We present an opto-thermal approach based on the use of active infrared thermography (IRT) for the study of texts hidden inside the bookbinding structure of ancient books. In particular we focus our investigation on the detection and characterization of texts on paper scraps, belonging to earlier handwritten or printed leaves, used for the making of bookbindings and lying between the end papers and the cover. A qualitative description of the physical mechanisms allowing the identification of texts is proposed and a comparative analysis of the results obtained by means of different IRT experimental configurations is presented. The results show that active IRT can be a very useful tool for the detection and the identification of underlying texts whose reading can provide useful information on the specific history of ancient books.

In this paper, we present an application of the infrared thermography to the study of illuminations. In particular, we analyze a 15th century antiphonary from the Biblioteca Angelica of Rome to characterize the conservation state and the structure of the illuminations on the occasion of its planned restoration. We show the results achieved from the stratigraphic investigation of the gilded surface, the parchment substrate and the underdrawing. The obtained information have been, then, used to direct the necessary restoration steps and also to assess the effectiveness of the treatments by a comparative analysis of the thermograms recorded before and after the restoration.

Infrared thermography (IRT) is a non-destructive technique that has recently been extensively applied to the investigation of cultural heritage. It provides information on the surface and subsurface structure of the artefacts by the analysis of the heat diffusion process within the sample. IRT has been successfully applied to the study of historic large structures and buildings most of the time by means of the so-called passive approach, where only the naturally occurring temperature changes in the sample are analysed. On the other hand, IRT has also been applied to the study of other art and historic artefact by applying the so-called active method where the thermal stimulation of the sample is required. In this article, an overview of the applications of active thermography to the investigation of art and historic artefacts will be presented and discussed.

Occupational exposure to chromium may cause airway inflammation and bronchial asthma. In this study we investigated the effect of chromium on the respiratory tract of exposed and non-exposed electroplating workers using spirometry and analysis of induced sputum (IS), exhaled breath condensate (EBC) and nasal lavage fluid (NLF). In both groups spirometry was normal; chromium in induced sputum was higher in exposed workers (7.90 +/- 0.855 microg/L, vs 1.78 +/- 0.075 microg/L; p0.001); no significant difference was found in induced sputum cellularity. Median nitrite concentration in EBC was significantly higher in exposed subjects (4.35 micromol/L, 5 degrees -95 degrees percentile: 1.88-10.13 vs 0.11 micromol/L, 5-95 percentile: 0-0.72) (p0.001). IL-6 and TNF-alpha were not detectable in EBC. Median IL-6 concentration in nasal lavage fluid was higher in exposed workers (5.72 pg/ml, 5-95 percentile: 0-65.25 pg/ml vs 0.28 pg/ml, 5-95 percentile: 0-1.7 pg/ml) (p0.01). No differences in Eosinophil Cationic Protein concentration were found. TNF-alpha was not detectable in NLF. Chromium in induced sputum correlated with nitrites in EBC. For the first time three non-invasive methods were used to assess changes in respiratory tract in workers exposed to chromium. The results suggest chromium exerts an inflammatory/irritative action on airways.

Background: The study objectives were to assess the ship physician's diagnostic accuracy in making the decision to air evacuate critically ill patients from cruise ships, to determine the outcome of these patients, and the overall benefit of air evacuation. Methods: From October 1999 to May 2000, we performed a prospective study of critically ill patients coming from cruise ships in the Caribbean and transported to our institution by air ambulance. Demographics, initial diagnosis, and treatment on board were collected by the triage officer at the time of the cruise physician's first call. In route complications and flight team composition were obtained from the air ambulance monitoring log. Patients were followed-up in the hospital for complications, outcome, and final diagnosis. Results: A consecutive series of 104 patients were considered for analysis. There were 65 men and 39 women (mean age: 68.7 years). Cruise physician's diagnosis was correct in more than 90% of the cases. Internal medicine and surgical conditions represented 80.8% and 19.2% of the cases respectively, falling mainly into three categories: cardiac (34.6%), neurological (20.2%), and digestive (14%). Two cardiac arrests and 1 ventricular fibrillation were successfully resuscitated and 5 of 15 myocardial infarctions received thrombolytic therapy on board. Air transfers were warranted in 96.1% of the cases and physician presence in the flight was considered appropriate in 97.6%. In route complications and mortality rate were 5.8% and 2.9% respectively, related to serious cardiac events. Among the 98 hospitalized patients, 10 patients developed new complications and 5 died. The overall mortality rate was 7.7%. Conclusion: The cruise industry appears off to a good start in the medical treatment of passengers needing air evacuation to a land based medical facility. There is room for improvement and adoption of American College of Emergency Physicians (ACEP) and International Council of Cruise Lines (ICCL) Health Care Guidelines are meaningful first steps. Analysis of Caribbean medical facilities and implementation of active telemedicine conferencing represent alternatives to air evacuation that need to be studied.