Hybrid nanomaterials and nanoparticles for the prevention of biodeterioration of cultural heritage objects

Resumen del trabajo presentado al IX Congreso Ciencia y Arte, celebrado del 17 al 19 de octubre de 2022.N

Nanomateriales antimicrobianos para prevenir el biodeterioro del patrimonio cultural

Resumen del trabajo presentado a la 9ª Jornada de Jóvenes Investigadores de Química y Física de Aragón, celebrada en Zaragoza el 16 de diciembre de 2021.Peer reviewe

Polyoxometalate‐Ionic Liquids (POM‐ILs) as anticorrosion and antibacterial coatings for natural stones

Resumen del póster presentado al RSC Chemical Nanoscience and Nanotechnology Early Careers Virtual Meeting, celebrado el 24 de marzo de 2021.Peer reviewe

Influence du faciès sur la fracturation dans les roches carbonatées

TOULOUSE3-BU Sciences (315552104) / SudocTOULOUSE-Observ. Midi Pyréné (315552299) / SudocSudocFranceF

Les calcaires du Bajocien de la cuesta du Dogger à Dom-le-Mesnil et Hannogne-Saint-Martin (Ardennes).

International audienc

Thermographic imaging for early detection of biocolonization on buildings

International audienceBiofilms developed on historical heritage buildings are made of various microbial communities settled and anchored in a substrate. They provide a good medium to the development of macroscopic vegetation which causes irreversible and physical damage to stone structure. Infrared thermography (IRT) measurements have been performed in laboratory scale to investigate the applicability of this non-destructive technique to an early detection of microbial biofilms on stone surface. Detecting biofilms before stone soiling is important in Cultural Heritage conservation to avoid both irreversible damage and building restoration costs.Active IRT was set up on a French limestone used in many French buildings and monuments. Samples were collected after six-months of exposure in an outdoor biofouling test during which they were colonized by microbial biofilms. They have been compared with controls with no biofilm. Experimental set-up has been carried out in dry and damp conditions to simulate different climatic conditions. First results displayed a different thermal response: stone surfaces with biofilm reached higher temperatures and they cooled down faster than row stones. Biofilm entailed a change of the stone thermal behaviour similar to a monolayer. IRT detected biofilm with a better efficiency in dry than in damp condition

Assessment of the combination of frost and salt solution on limestonedurability: application to the Massangis limestones (Burgundy, France)

International audienceChange of facies within a quarry can be subtle and yet lead to contrasting behaviors when they are usedas building stones. The classic characterizations of materials according to the standards do not alwaysmake it possible to highlight their differences and to understand their weathering behavior.In the Burgundy region, middle of France, a quarry operated by POLYCOR and ROCAMAT providesdifferent facies of oolitic type Jurassic limestones called Massangis. They are used mainly flooring, wallcladding and solid wall. These limestones have similar appearances (shade of color and texture). Thevarious facies are not linked to the stratigraphy but by the color change observed within the differentstone banks. Except for their color and according to the standards, these facies show only slight variationsof properties. However, they exhibit contrasted behaviors in use, particularly in the case of combination ofsalt and frost action. In addition, a lower resistance of the light-colored facies pale beige compared to theyellow facies is observed.The use of standards to assess durability of building stones usually means the measurement of the actionof only one factor at a time that is not what occurs on buildings where stones are often submitted to acombination of weathering factors. Thus, some stones that were supposed to resist according tostandards, show early degradation when used as building stones which is the case of some facies ofMassangis. With the aim to assess the specific properties of each facies and to understand their behaviorsto a combination of weathering factors, the 4 quarried facies were characterized by specific intrinsicproperties: total porosity with water and pore distribution with mercury porosimetry and study of coloredthin sections, transfer properties by capillarity and evaporation. Then stones were subjected toaccelerated ageing tests combining the effect of frost and salts. The monitoring of the alteration wascarried out by measuring the speed of the acoustic waves.At the level of the quarry, the 4 facies are identified by the operator according to their color. Two clearfacies are defined, the light shaded facies (MALP) from the Malpierre quarry next to the main quarry andthe nuanced clear Massangis facies (MCN) from the main quarry called Val d’Arion. The two other faciesare the facies corresponding to the yellow Massangis (MJ) and the light beige facies (MBC) composed of amixture of light and yellow facies.The clear facies (MALP and MCN) are quite different facies despite their similar aspect. The MALP facies ismore porous than the MCN facies (MALP = 14.14% / MCN = 12.70%). However, MALP has a 48H porosityand a saturation coefficient lower than MCN. The MCN facies has an unimodal and microporous networkcompared to MALP. Its range of pores is homogeneous allowing good circulation of fluids.The light beige Massangis facies (MBC) has a lower porosity (12.05%), but a high saturation coefficient(82%). The mercury porosimetry study highlighted the presence of fairly heterogeneous distribution ofaccess radii. Within the quarry, this facies corresponds to more or less clear or yellow zones depending onthe extraction zone, complicating the identification of the facies type.Finally, the yellow Massangis (MJ) behaves quite differently from the other facies. This facies has thelowest porosity (10.36%) with a 48H saturation coefficient of 44%. It has a very heterogeneous range ofpore access that does not allow good capillary saturation of the stone (26%).The results of the weathering tests simulating unidirectional freezing of parallelepipedal samplessubmitted to capillary absorption with water and with salt solutions will allow to assess the behavior of the 4 facies according to their porous network

Chlorophyll Fluorescence and Colorimetric Analysis for Monitoring the Algal Development on Biocide-Treated Stone

International audienc

Geochemical characterization of “Lorraine limestones” from the SaintPaul Cathedral of Liège (Belgium): assumptions for the true provenance of the building stones

We investigate the provenance of the ochre building stones called “Lorraine limestones” used for architectural specifc elements of the Saint-Paul Cathedral in Liège (Belgium) between the thirteenth and ffteenth century. A multi-analytical approach, including archives study, petrography and Rare Earth Elements geochemistry, has been performed to characterize the stones used in the church and to compare them with ochre limestones outcropping in the north-east of the Paris Basin. Our study suggests that a very restricted geographical area near the ancient port of Donchery (Ardennes, France) including Dom-le-Mesnil and Hannogne ancient quarries of Bajocian limestones (Middle Jurassic) should clearly be regarded as the potential origin location for the stones used in the Saint-Paul Cathedral.project n°706579