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Page 15 of 939 Results 141 - 150 of 9382

Agnese De Carlo, Valerio Graziani, Paolo Branchini, Luca Tortora
Monoazo and Isoindoline Yellow reactivity in presence of Pb, Ti, Zn-based white substrates

This work explores the effects of accelerated aging conditions on two yellow synthetic organic pigments with good light fastness: PY 1 and PY 139 also known as Hansa Yellow G (or Monoazo yellow) and Isoindoline Yellow, respectively. The reactivity of PY 1 and PY 139 in presence of reactive inorganic whites such as basic lead carbonate, titanium oxide, and zinc oxide was investigated. The accelerated aging process was achieved through UV irradiation in a home-made climatic chamber for a set of bilayer paint mock-ups. Bilayered samples were realized to simulate the painting technique of superimposing multiple layers of thinly applied paint. Colorimetry, Fourier-Transform Infrared Spectroscopy, and Photoluminescence Spectroscopy were adopted to reveal physico-chemical changes occurred in such samples.

Eleonora Marconi, Luca Tortora
Synthesis of titania nanoparticles in W/O microemulsion: moving the production toward a green approach

In this work, we report an easy, fast, reproducible, and low-temperature microemulsion procedure for the large-scale production of titania nanoparticles (NPs). The synthesis involves a polycondensation reaction of alkoxide precursors during the heating at 70 °C. A W/O microemulsion with a volume ratio of 1:1 was obtained using cetylpyridinium bromide (CPB) as a cationic surfactant. Structural and functional characterization of the samples was conducted using X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The photoactivity of the nanostructured titania was evaluated by measuring the photodegradation of Methylene blue (MB). The results indicate that the photoactivity depends on the sinterization grade of the titania nanoparticles. Commercial titania nanoparticles (P25) were used as a reference material commonly employed for coating stone protection in the field of Cultural Heritage Conservation.

Francesca Boccaccini, Aurelio Barbetta, Elena Messina, Marianna Pascucci, Cristina Riccucci, Gabriella Di Carlo
Novel, effective and safe coatings for the protection of copper-based artefacts

Degradation processes in cultural heritage metal artefacts represents a critical issue since they can irreversibly compromise the conservation status of valuable works of art. The products used to hinder these processes are mainly based on harmful or toxic corrosion inhibitors and solvents. Namely, large amounts of organic solvents are typically used by conservators for the application and removal of protective materials. In the last decades, the search for new materials that can simultaneously satisfy protective, aesthetic and safety requirements is receiving an increasing attention.
In this contest, we have focused our attention on the development of sustainable polymer coatings that can provide an active protection and that are easy to be applied and removed using water-based solvents. A green polymer from renewable sources, such as chitosan, was selected and functionalized with anticorrosive species. Validation tests were performed on model copper-based substrates with different composition and surface finish. The performances were compared with a commercial benchmark.

Arianna Ceci, Luca Lanteri, Claudia Pelosi, Paola Pogliani, Sabrina Sottile
Analysis of materials of wax Christ-children from the Monastery of Santa Rosa in Viterbo

This paper reports the results of the analysis performed on three wax Christ-children (wax Bambinelli) preserved in the monastery of Santa Rosa in Viterbo. The analysis was performed on the occasion of the restoration, recently concluded, with the aim at supporting the working operations. The characterisation of the materials was particularly relevant for this kind of objects because they are little studied being considered of lesser artistic relevance than other artworks. But the wax babies are very important for their religious values and for technical details and peculiarities: apart from wax, precious textiles and decoration can be found in their dresses and ornaments. The materials were characterised by 2D and 3D ultraviolet fluorescence imaging, X-ray fluorescence spectroscopy, Fourier Transform Infrared spectroscopy, optical microscopy.
These techniques were used for investigating both the waxy mixture composition and the textile fibers of the babies hair

Angelja Kjara Surca, Mohor Mihelčič
Electrochemistry and vibrational spectroscopy in investigation of protective coatings for bronze artworks

Herein are discussed the possibilities of how to exploit vibrational spectroscopic and electrochemical techniques in the studies of protective coatings for bronze artworks. Protective coatings for bronze 85,555 are prepared on the basis of polyurethanes or fluoropolymers. Reflection-absorption infrared spectroscopy under near grazing conditions is described as a powerful tool for studying the surfaces of bronze when exposed to various conditions (solutions, strippers, temperature). Electrochemical techniques, especially the potentiodynamic polarization technique, are very powerful in the evaluation of protective coatings. A combination of electrochemical and spectroscopic techniques, however, enables to follow changes in the protective coating that occur with an increase in an anodic potential. This is an accelerated test and similar changes are expected to occur in the protective coatings with time, i.e., exposure to atmospheric conditions (rain, humidity …). Various solutions were also tested as strippers to evaluate the removability of coatings.

Penka Girginova, Cristina Galacho
Cellulose ethers and nanoconsolidants: preliminary observations on the suitability of the use of cellulose derivatives in the synthesis of nanolime particles

This communication reports the preliminary results of our ongoing research on the effect of addition of cellulose-derivatives, such as cellulose ethers, in the synthesis of calcium hydroxide (Ca(OH)2) micro-sized particles. Particles of Ca(OH)2 were synthesised without and with addition of different amounts hydroxypropyl methylcellulose (HPMC). The obtained particles were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR). Our preliminary results anticipate that syntheses with addition of HPMC originated the formation of smaller and more uniform in shape and size Ca(OH)2 particles in comparison with the Ca(OH)2 particles synthesized without addition of HPMC. This study contributes to the urgent need of innovative non-toxic sustainable materials, compatible with the original artworks, with long-term efficiency and easy for application.

Erica Sonaglia, Maria Paola Bracciale, Maria Laura Santarelli
Recycled bacterial nanocellulose membranes as novel green gels for the cleaning of cultural heritage surfaces

The removal of extraneous materials without changing artifacts original properties and appearance is a crucial aspect in the cleaning of cultural heritage. In this scenario, gels proved to be useful thanks to solvent retention and its controlled release on surfaces. In the past, synthetic polymer-derived gels attracted interest thanks to their good performance. However, in recent years, nanotechnologies and green chemical approaches have created great interest also in restoration and conservation applications. The aim of this paper is to demonstrate the possibility to use bacterial nanocellulose (BNC) as a green gel material in cleaning operations. Recycled BNC, a by-product from the fermented beverage Kombucha, is used, which represents an innovative application. Purified by-products are investigated by means of different analytical techniques to characterize the chemical structure, crystallinity, microstructure, thermal behaviour, tensile behaviour, water retention capacity (WRC) and organic solvent retention capacity (OSRC). Materials show good mechanical behaviour, diffuse nanodimension and high WRC and OSRC. A selected BNC gel is used in tests on the removal of wax, one of the most widespread deposits of dirt on different surfaces. The experiment demonstrates cleaning efficiency for removing beeswax after one hour and a weak removal of microcrystalline wax, showing BNC s potentiality as a bio-based, bio-degradable and renewable gel.

Cecilia Giorgi, Marilena Cozzolino, Vincenzo Gentile, Paolo Mauriello
Unveiling the Hidden Past: exploring the historical evolution of Borbona (Rieti, Italy) through archaeological surveys and geophysical prospections

The research project aims to uncover the unknown territory and trace its origins. It s conducted by the ISPC CNR to study the historical and archaeological context of Borbona (Rieti, Italy) with the collaboration of the Department of Agricultural Environmental and Food Sciences (University of Molise) for the geophysical prospections. Despite the limited historical and archaeological studies on Borbona, unexpected discoveries emerged during the research. Through various activities, including surveys and analysis of findings, the project has identified ancient habitation areas and significant Roman architectural fragments. The research seeks to transmit the history and culture of Borbona to future generations, fostering a sense of belonging. Protecting historical heritage and areas at archaeological risk, enhancing and promoting existing cultural assets, represent fundamental actions to increase the country s attractiveness in the present and preserve its identity in the future.

Joel Aldrighettoni, Barbara Marana, Maria Grazia D'Urso
War-scapes testimonial gradient: a multi-criteria approach as a proactive tool for choosing future practices of enhancement

The vastness of the material permanences of the Great War within contemporary landscapes imposes on the stakeholders that want to take care of them the need to identify new operational tools capable to calibrate a map of intervention priorities. This contribution presents the elaboration of a methodological approach capable of dealing with the complexity of this fragile heritage through a knowledge-based skeleton useful for comparing different territorial areas by assigning them different testimonial gradients with respect to the level of knowledge of specific pre-established indicators. Thanks to a multi-criteria analysis matrix based on analytical-hierarchical processes (AHP) weights and quantities are assigned to the indicators and sub-indicators under analysis thus highlighting, for each analyzed area potentialities and criticalities that become indispensable for planning future enhancement interventions. This paper presents the application of this innovative approach on the permanences of three fortified systems on the Vezzena Plateau in Trentino (Italy), along what, a hundred years ago, was the former first border line between Italy and the Austro-Hungarian Empire. This study case was sponsored by the Superintendency of the Autonomous Province of Trento that needed an analytical tool to identify on which of these three areas, currently in a state of neglect and degradation, to program future conservation and enhancement plans.

Giulia Fiorini, Maria Alessandra Tini, Francesco Montelli, Gabriele Bitelli
Comparison of two technologies in 3D surveying of Real Estate Assets and Cultural Heritage

Accurate three-dimensional (3D) data from indoor spaces holds significant importance in various fields like real estate management, industrial archaeology and Cultural Heritage. Villa Maraffa complex, located near Ravenna (Italy), served as a case study for employing and comparing advanced technology and sensors in surveying these contexts. To acquire data, the sensors used were Matterport Pro 2 and Leica RTC360. The first one, mainly developed for real estate surveys, has been chosen because of the efficiency and cost-effectiveness in generating point clouds, albeit with lower precision compared to the Leica RTC360 Laser Scanner, the other sensor employed in this study. The focus of the paper is on assessing the point cloud s quality, with an analysis of the Matterport data, including global and specific evaluations. Potential issues like incomplete data and misalignment are identified by comparing coordinates from the Leica scanner. The results are examined to find an optimal solution for a prompt, precise, and well-timed survey, enabling a complete digital reconstruction of the object.

Page 15 of 939 Results 141 - 150 of 9382