•High temperature and relative humidity increase the degradation rate.•Plasticizer type does not affect the degradation, the content does. High-MW polymers are more stable than shorter chains.•The ...activation energy of dehydrochlorination observed as yellowing is 86 ± 3 kJ/mol.•Use the damage function to predict lifetime of heritage objects.•Identify objects in collections prone to degradation.
Yellowing of plastic objects as a consequence of chemical degradation is a common heritage conservation challenge. In the case of poly(vinyl chloride) elimination of hydrogen chloride leads to the formation of polyene sequences that act as chromophores. The objective of this work was to quantitatively evaluate the rate of degradation observed as yellowing, as relevant to room conditions during long-term storage of heritage collections. Degradation was quantified as increase in the b* colour coordinate during accelerated degradation at 50 and 70 °C as a function of temperature, relative humidity, plasticizer content, and polymer molecular weight. The significance of each variable was investigated with multiple linear regression. Lower temperature, lower relative humidity, higher polymer molecular weight and higher plasticizer content were associated with lower degradation rates. The activation energy of 86 kJ/mol was calculated. The concept of ‘1- °C-equivalent’ is introduced to enable variable prioritisation from a heritage management aspect. The resulting model can be used to shape environmental management guidelines and identify the most vulnerable objects in heritage collections.
In this study, X-Ray Fluorescence Spectrometry (XRF), Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) and Secondary Ion Mass Spectrometry (SIMS) have been used to assess the ...transfer of ions between iron-gall inks and indicator papers soaked in 4:7-diphenyl-1:10-phenanthroline. Such indicators are commonly used in the conservation practice to detect Fe(II) ions and diagnose a presence of ink corrosion phenomena in historical manuscripts. For this purpose four different model inks with variable Fe:Cu proportions were prepared on the basis of gall nuts extract mixed with FeSO4.7H2O, CuSO4.5H2O and Gum Arabic. Obtained results indicate that apart from the main components of inks (S, Fe and Cu) also other elements can migrate to indicator test papers. Collected XRF and LA-ICP-MS data were consistent in their potential for reconstructing major elemental composition of model inks on the basis of indirect analysis with indicator test papers. LA-ICP-MS extended the range of learning into the trace elemental composition, while SIMS allowed observations of structurally significant fragment ions (ML2+, ML+, M+) where L = 4:7-diphenyl-1:10-phenanthroline and M = Fe or Cu ions.
Display omitted
•XRF, LA-ICP-MS and SIMS were used to assess the transfer of ions between iron-gall inks and indicator papers soaked in Bphen.•Evidence that elements other than the main components (S, Fe and Cu) also migrate from inks to the indicator papers when used.•Fragment ions ML2+, ML+, M+ (where L=4:7-diphenyl-1:10-phenanthroline and M=Fe or Cu ions) were detected by SIMS.
The present research exploits the strengths of external reflection FT-IR spectroscopy to non-invasively study heritage plastic objects through inspection, for the first time, of the wide spectral ...range including the near- and mid-IR (12500-350 cm−1). Unlike most of previous works on historical plastic objects, reflection-mode spectra were not corrected for the unfamiliar surface reflection profiles to the more recognizable absorption-like band shapes. This avoided data misinterpretation due to ill-suited Kramers Krönig correction when volume reflection is also present or when highly absorbing IR compounds generate Reststrahlen bands.
The inspection of the enlarged spectral range allowed the detection of fundamental, combination and overtone bands which provided reliable identification and semi-quantitative characterization of different polystyrene-based co-polymers. Furthermore the variation of the plastic optical properties across the explored spectral range allowed us to sample the plastic materials to different depths in the mid- and near-IR regions, so as to probe the chemistry at the surface and in the plastic bulk, respectively, in a non-invasive manner. This proved particularly useful to observe spectral markers of surface degradation occurring in historical ABS-based polymers.
Display omitted
•External reflection FT-IR for non invasive studies of historical plastic objects.•Non invasive identification of polymers.•Estimation of the relative content of monomers in PS-based co-polymers in historical plastic objects.•In situ monitoring of degradation markers in plastics for preventive conservation of historical plastic objects.
•Combined microwave/optic approach for detection and characterization of detachments of wall paintings.•Risk falling assessment of the detachments and their classification in “stable”, ...“almost-stable” and “unstable”.•Reconstruction of wall painting stratigraphy by non-destructive techniques.•Proof of concept of the proposed tool on the wall paintings masterpiece of Masolino, Masaccio and Filippino Lippi in the Brancacci chapel in Florence, with the support of laboratory tests on proper mock-ups.
This paper evaluates the improvements in wall paintings diagnostic achievable by the synergistic combination of DHSPI, SIRT and MWR techniques. These innovative portable and non-destructive techniques for in-situ diagnostic were tested in laboratory on mock-ups mimicking the real conditions of wall painting defects (such as detachments, cavities and cracks), and on the frescoes painted by Masolino, Masaccio and Filippino Lippi (between 1422 and 1475) in the Brancacci Chapel in the church of Santa Maria del Carmine in Florence, Italy. This research activity was part of the Brancacci Chapel diagnostic and monitoring project, where the assessment of the state of conservation is a mandatory prerequisite for planning the subsequent restoration work. In common practice, restorers make the preliminary evaluation on the state of conservation of the wall paintings by visual and tactile inspection, without the use of any special scientific instrumentation. Cracks, cavities, lack of material, detachments, out-of-plumb and deformation of (non-)structural elements are reported in a condition report to document the state of conservation at a given point in time. In particular, the detachments are recognized by the tap test, but this is a discretionary and highly subjective method. Thus, there is a strong demand for the development of a portable and non-destructive approach that refines this preliminary survey with objective data. Here, we present the results produced by the combination of MWR (useful for the dimensional characterization of hidden defects in the wall) and DHSPI-SIRT to identify the extent of deformations induced by thermal stimulus, providing an objective confirmation of the preliminary investigation performed by restorers, in which the detachments were indicated as “stable”, “not very stable” and “unstable”, i.e., close to falling. The integrated use of these techniques in situ, supported by a laboratory study on ad-hoc prepared mock-ups, proved to be suitable for a quantitative evaluation of damage risk to guide restoration strategy accordingly.
Laser-induced breakdown spectroscopy (LIBS) is a versatile elemental analytical technique whose basic elements were described as early as 1962, shortly after the invention of a pulsed laser. Since ...that time, LIBS has been applied for elemental characterization of various applications. In this work, we review the evolution of LIBS characterization of artworks' materials applications and the development of the LIBS technique for cultural heritage during the years 2015–2020. The LIBS technique has faced and overcome challenges by analytical studies of conservation/restoration and archaeological objects. These challenges required improvements in the LIBS technology in order to obtain good reproducible signals (high S/N, sensitivity) and more reliable quantitative analysis. They also encouraged the LIBS research community to focus on instrumentation development to minimize laser impact, to increase miniaturization (enabling in situ characterization), and to combine different spectroscopic techniques. We aim to encourage more people working on heritage science to use this technique, for whom LIBS may be a brand-new elemental analysis technique, and aim to motivate more LIBS researchers to continue developing the LIBS technique in order to address more issues on conservation, restoration, and archaeology.
Display omitted
•LIBS for heritage science applications in the last six years.•Review of recent evolution of LIBS instrumentation from portable LIBS to hyphenated techniques.•New trend and needs in cultural heritage material characterization.
On the occasion of the upcoming twentieth anniversary of the adoption of the UNESCO Convention on the Safeguarding of Intangible Cultural Heritage , it is important to emphasise the role of ...intangible cultural heritage in preserving the identity of an individual nation. This paper analyses the Science and Social Studies textbooks for the 4th grade of elementary school. The aim of the paper is to determine the representation of intangible cultural heritage inscribed on UNESCO's list of cultural goods by analysing textbooks and to provide guidelines for approaching this topic. The review of textbooks revealed differences in the approach to coverage relating to content related to intangible cultural heritage in textbooks by different authors and different publishing houses. It was observed that different authors approach the topics of cultural heritage differently, and intangible heritage is represented differently in different textbooks. In the majority of textbooks, intangible cultural heritage inscribed on the UNESCO list is well presented, but it is mostly mentioned as such without additional explanations and visual representations. It is necessary to approach this topic in education in a way that will encourage students to be active and participate in preserving the intangible cultural heritage that is a part of each of them, with a textbook being just one of the available tools in the teaching process.
Povodom nadolazeće dvadesete obljetnice donošenja UNESCO-ove Konvencije o zaštiti nematerijalne kulturne baštine važno je istaknuti ulogu nematerijalne kulturne baštine za očuvanje identiteta pojedinog naroda. U radu je napravljena analiza udžbenika iz Prirode i društva za 4. razred osnovne škole. Cilj je rada bio analizom udžbenika utvrditi zastupljenost nematerijalne kulturne baštine koja je upisana na UNESCO-ov popis kulturnih dobara te dati smjernice za pristup ovoj temi. Pregledom udžbenika utvrđene su razlike u pristupu obrade sadržaja koji se odnose na nematerijalnu kulturnu baštinu u udžbenicima različitih autora i različitih izdavačkih kuća. Uočeno je kako različiti autori različito pristupaju temama kulturne baštine te je nematerijalna baština različito zastupljena u različitim udžbenicima. U većini je udžbenika dobra pojavnost nematerijalne kulturne baštine s UNESCO-ovog popisa, ali se ona kao takva uglavnom spominje bez dodatnih objašnjenja i slikovnih prikaza. Potrebno je ovoj temi u odgoju i obrazovanju svakako pristupati na način koji će poticati učenike na aktivno djelovanje i njihovo sudjelovanje u očuvanju nematerijalne kulturne baštine koja je dijelom svakoga od njih, a udžbenik je pri tome samo jedno od sredstava u nastavnom procesu.
The molecular characterization of organic materials in samples from artworks and historical objects traditionally entailed qualitative and quantitative analyses by HPLC and GC. Today innovative ...approaches based on analytical pyrolysis enable samples to be analysed without any chemical pre‐treatment. Pyrolysis, which is often considered as a screening technique, shows previously unexplored potential thanks to recent instrumental developments. Organic materials that are macromolecular in nature, or undergo polymerization upon curing and ageing can now be better investigated. Most constituents of paint layers and archaeological organic substances contain major insoluble and chemically non‐hydrolysable fractions that are inaccessible to GC or HPLC. To date, molecular scientific investigations of the organic constituents of artworks and historical objects have mostly focused on the minor constituents of the sample. This review presents recent advances in the qualitative and semi‐quantitative analyses of organic materials in heritage objects based on analytical pyrolysis coupled with mass spectrometry.
Analytical pyrolysis is experiencing previously unexplored potential, thanks to recent instrumental developments. Recent advances in the heritage field enable the investigation of several organic materials in artistic and historical objects that are macromolecular in nature, or which undergo polymerization upon curing and ageing, by strategies based on analytical pyrolysis coupled with mass spectrometry.
Abbiamo intervistato l’attuale Direttrice del SIMPOSIO CIPA 2023 Firenze Prof. Grazia Tucci. Il 29° Simposio CIPA Heritage Documentation partirà nella prestigiosa cornice di Palazzo Vecchio - Salone ...dei Cinquecento - per proseguire, in una settimana di incontri e dibatti scientifici, presso Il Centro Didattico Morgagni dell'Università degli Studi di Firenze.
Abbiamo intervistato l’attuale Direttrice del SIMPOSIO CIPA 2023 Firenze Prof. Grazia Tucci. Il 29° Simposio CIPA Heritage Documentation partirà nella prestigiosa cornice di Palazzo Vecchio - Salone ...dei Cinquecento - per proseguire, in una settimana di incontri e dibatti scientifici, presso Il Centro Didattico Morgagni dell'Università degli Studi di Firenze.
Abbiamo intervistato l’attuale Direttrice del SIMPOSIO CIPA 2023 Firenze Prof. Grazia Tucci. Il 29° Simposio CIPA Heritage Documentation partirà nella prestigiosa cornice di Palazzo Vecchio - Salone ...dei Cinquecento - per proseguire, in una settimana di incontri e dibatti scientifici, presso Il Centro Didattico Morgagni dell'Università degli Studi di Firenze.
