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The present work focuses on the diagnosis of the damage induced by air multi-pollutants on the Centennial Hall, situated in one of the most industrialized and polluted regions of Poland, in close neighborhood of coal power stations. In order to investigate the impact of multi-pollutants on the cement built heritage samples of damage layer and underlying material were collected from the building, taking into account rain exposure (sheltered, partly sheltered and washed out areas) and analysed by range of analytical techniques: optical and scanning electron microscopy, X ray diffractometry, differential and gravimetric thermal analysis, ion chromatography, flash combustion/gas chromatographic analysis, inductively coupled plasma-optical emission spectrometer. The results obtained show that the surface deterioration of the Centennial Hall is mainly caused by deposition of SO2 and fly ash from coal combustion, and subsequent interaction with the cement components. These results for the first time demonstrate the impact of coal power stations on black crust formation on cementitious materials.

Nell’ambito di un progetto finalizzato allo studio delle diverse tipologie di degrado causate dall’inquinamento atmosferico a carico del patrimonio culturale costruito, in questo lavoro sono state prelevate croste nere in 4 differenti siti (3 europei e 1 nord africano) e caratterizzate mediante cromatografia ionica e spettroscopia a emissione atomica e di massa. I risultati ottenuti mostrano come in tutti i luoghi oggetto di studio, l’SO2 abbia un ruolo prioritario nella formazione delle croste nere. É stato inoltre identificato l’impatto di fonti inquinanti locali antropiche e di sorgenti naturali sul degrado degli edifici considerati, come le emissioni da combustione di carbone e da trasporto, sia ferroviario che veicolare, nel sito di Colonia, l’aerosol marino nei siti costieri di Salè ed Oslo, i sali disgelanti ad Oslo e precedenti trattamenti di restauro nel sito di Firenze.

The available scenarios of multi-pollutants trends in Europe indicate a shift in modern urban atmospheres from and SO2 dominated situation to a multi-pollutant situation, linked to the driven role played by traffic in determining the overall pollution in urban centres. In view of the proven overwhelming influence of mobile combustion sources in determining the future urban atmosphere, “modern’’ soiling on built heritage will be likely to contain primarily organic carbon (OC). This will imply a change in composition of damage layers, which will presumably assume a yellow-brown colouration. The EC TeACH project (Technologies and tools to prioritize assessment and diagnosis of air pollution impact on immovable and movable cultural heritage) sets out to understand the different types of damage on cultural heritage that can be expected in the future, due to changes in pollutants, both in terms of typology and concentration. Results achieved within this still running project on the composition of damage layers, collected and analysed from different monuments in Europe, will be presented and discussed. Elaboration of carbon fractions data will be liked in particular to colourimetric parameters (L*, a*, b*), with the aim of exploring the application of monitoring of colour change of architectural surfaces as potential strategy for preventive conservation.

The available scenarios of multi-pollutants trends in Europe indicate a shift in modern urban atmospheres from and SO2 dominated situation to a multi-pollutant situation, linked to the driven role played by traffic in determining the overall pollution in urban centres. In view of the proven overwhelming influence of mobile combustion sources in determining the future urban atmosphere, “modern’’ soiling on built heritage will be likely to contain primarily organic carbon (OC). This will imply a change in composition of damage layers, which will presumably assume a yellow-brown coloration. The EC TeACH project (Technologies and tools to prioritize assessment and diagnosis of air pollution impact on immovable and movable cultural heritage) sets out to understand the different types of damage on cultural heritage that can be expected in the future, due to changes in pollutants, both in terms of typology and concentration. To accomplish this goal, from the technological point of view the project aims to develop a non invasive device for the continuous monitoring of the damage caused on monuments located outdoor by changing pollution impact, based on the change of colour of the architectural surface. A prototype is currently under testing at 5 monuments located in urban sites in Europe and one in the Mediterranean area, characterized by different environmental and climate conditions: Cologne Cathedral (Germany), S. Maria del Fiore Cathedral in Florence (Italy), the National Gallery in Oslo (Norway), the Arriaga Theatre in Bilbao (Spain), the National Museum in Cracow (Poland), the historic walls of Salè (Morocco). Colorimetric analyses directly at the building surface for blackening/colour change characterisation using a portable spectrophotometer. Results achieved within this still running project on the composition of damage layers will be presented and discussed. Elaboration of carbon fractions data will be liked in particular to colorimetric parameters (L*a*b*), with the aim of exploring the application of monitoring of color change of architectural surfaces as potential strategy for preventive conservation.

The work focuses on the diagnosis of the damage induced by air multi-pollutants on the Centennial Hall, situated in one of the most industrialized and polluted regions of Poland, in close neighborhood of coal power stations. In order to investigate the impact of multi-pollutants on the cement built heritage samples of damage layer and underlying material were collected from the building, taking into account rain exposure (sheltered, partly sheltered and washed out areas) and analysed by range of analytical techniques: optical and scanning electron microscopy, X ray diffractometry, differential and gravimetric thermal analysis, ion chromatography, flash combustion/gas chromatographic analysis, inductively coupled plasma-optical emission spectrometer. The results obtained show that the surface deterioration of the Centennial Hall is mainly caused by deposition of SO2 and fly ash from coal combustion, and subsequent interaction with the cement components. These results for the first time demonstrate the impact of coal power stations on black crust formation on cementitious materials.

Very few scientific studies have been dedicated to the impact of multipollutants on 20th-century built heritage. The effect of the impact of gaseous pollutants and aerosols on cement mortars in urban areas, especially the formation of black crusts, is still not well documented, making this issue a challenging area of research. The present work focuses on the evaluation of the impact of air multipollutants on the Casa Galleria Vichi, a modern concrete building dated 1911, located in the center of Florence (Italy). In order to investigate the surface damage induced by air multipollutants, samples of deterioration layers (crusts) and underlying material were collected and analysed. The results obtained from the experimental activity performed on the damage layers indicate that gypsum, due to the deposition of sulphur atmospheric compounds, is the main damage product. Furthermore the particulate matter found embedded in the gypsum matrix, shows that oil fossil fuel combustion is the main cause of building surface blackening.

It is generally agreed that the role played by aerosols in determining the air quality in urban areas is steadily increasing. As well as being among the main agents responsible for today’s atmospheric pollution, atmospheric particles are also recognized to participate actively in damage layer formation. In fact, recent years have witnessed a marked acceleration in surface soiling phenomena, as can be observed in the continual blackening of monument surfaces located in polluted areas. While numerous authors have performed detailed studies on the impact of the sulphation process in monument decay on a world-wide scale, surface blackening remains in need of in-depth investigation. The EC project CARAMEL (Carbon content and origin of damage layers in European monuments) has as one of its fundamental work steps the analytical study of black crusts collected at different monuments located in European urban sites. The aim is to create a data base of the carbon fraction concentrations present, and understand their relationship with the content of aerosol carbon components.

To investigate the short-term optical, chemical and morphological changes in Invisalign appliances.One 'as-received' Invisalign aligner, one 'as-received' Invisalign aligner immersed in artificial saliva for 14 days and 10 Invisalign aligners worn by 10 randomly selected patients for 14 days were used. Fourier'transform infra-red microspectroscopy was used to characterise any molecular changes on the surfaces of the appliances, spectrophotometry was used to evaluate any changes in colour and transparency, scanning electron microscopy and energy dispersive X-ray microanalysis were used to examine the surface morphology and elemental composition of deposits on the surfaces of the aligners and gas chromatography-mass spectrometry was used to identify substances released from the aligners into the artificial saliva.Aligners worn for 14 days had microcracks, abraded and delaminated areas, localised calcified biofilm deposits and loss of transparency. Monomers and/or by-products were not released from the aligner suspended in artificial saliva for 14 days, which suggests that the material is chemically stable.Further studies are required to evaluate how intra-oral conditions may influence the optical properties and chemical stability of the aligners.

It has been recognized that many modern buildings undergo rapid deterioration, especially in areas with high air pollutant concentrations. It is assumed that the deposition of gaseous multipollutants and aerosols plays a major role in causing the deterioration of monuments and built cultural heritage in European cities. While the deterioration process due to air pollutants and particle deposition is well studied in stones, particularly limestone, sandstone and granite, in the case of cement materials the subject has yet to be explored. This work focuses on the investigation of the impact of air multipollutants on concrete architecture in current urban atmospheres. The diagnosis of surface layers considering location of buildings, is a major issue in this research. To this end laboratory analyses have been preformed on samples from buildings exposed in different urban areas: Centennial Hall of 1913 (Wroclaw, Poland, close to a power station); Chiesa dell'Autostrada del Sole of 1963 (Florence, Italy, close to the motorway) and Casa Galleria Vichi of 1911 (Florence city centre). The samplings were carried out taking into account different levels and parts of the buildings, in washed out, sheltered and partly sheltered areas. The characterization of collected surface layers and cement mortar samples was performed using a range of analytical methods, including optical and scanning electron microscopy, x-ray diffraction, ion chromatography, induced coupled plasma-optical emission spectroscopy, differential and gravimetric thermal analysis and CHNSO elemental analysis. The quantitative results from the experimental work will be presented and discussed, in order to achieve an exhaustive picture of the main causes leading to concrete deterioration in the buildings under study.