Consolidating materials for the volcanic tuff in western Mexico

The diversity of volcanic tuff buildings standing in Western Mexico is large, therefore, it was considered relevant to evaluate and synthetize different stone consolidants that could be applied in the regional weather conditions and renew the stability of those buildings; since the commercial products are developed and tested in foreign countries, and in some cases, when applied under the weather conditions of Mexico, the results differ from those reported. For the altered tuffs from Santa Mónica's Church in Guadalajara, Mexico, the deterioration mechanism of the local tuff was determined, thus a silicate and aluminosilicate consolidants were synthesized by the sol-gel method and applied to altered tuffs in order to evaluate their performance from structural to macroscopic level.     

Non-marketizing agents in the study of markets: competing legacies of performativity and actor-network-theory in the marketization research program

One line of criticism leveled against studies of markets inspired by the economization research program [Çal??kan, K. &; Callon, M. (2009) ‘Economization, part 1: shifting attention from the economy towards processes of economization’, Economy and Society, vol. 38, no. 3, pp. 369–398 and Çal??kan, K. &; Callon, M. (2010) ‘Economization, part 2: a research programme for the study of markets’, Economy and Society, vol. 39, no. 1, pp. 1–32.] is that their analytical priorities reflect an economics-centric perspective: they prioritize the study of market exchange itself and of agents promoting market framing, while leaving non-economic agendas and the broader contexts of markets both understudied and undertheorized. This weakness tends to be attributed to contingent analytical priorities, which can be remedied by extending the program’s focus without changing its theoretical tenets. This article, in contrast, suggests that these analytical priorities stem from a theoretical tension within the program, which is caused by the complete, instead of a selective adoption of the theoretical tools of the performativity agenda in the marketization program. As a result, while the program promotes the inclusion of non-marketizing agents through the notion of co-performation, its call to focus on those phenomena that agents qualify as ‘economic’ and on the making of market exchange delimits the analysis of non-marketizing agents to their helping/hindering effects on market framing. The solution proposed is to reassess some of the performativity-inspired tools of the program in favor of a more ANT-inspired approach to markets.     

Consolidation and protection by nanolime: Recent advances for the conservation of the graffiti,Carceri dello Steri Palermo and of the 18th century lunettes,SS. Giuda e Simone Cloister,Corniola (Empoli)

Nanolime dispersed in 2-propanol was extensively used for the consolidation of wall paintings. The knowledge of the advances of this methodology dealing with all the possible effects associated with the nanolime new material in conservation is fundamental to assess and improve the technique. In this paper, four different dispersions of Ca(OH)₂ nanoparticles were characterised by Small Angle X-rays Scattering technique (SAXS) and Transmission Electron Microscopy (TEM) in order to achieve information on size, shape, polydispersity, agglomeration, and crystal structure (by SAED patterns) of the particles. Once characterised, the dispersions were tested in two different case studies, the Carceri dello Steri in Palermo with their graffiti and the 18th century lunettes at the SS. Giuda e Simone Cloister, Corniola (Empoli) with their lime-based mural paintings. The treated samples were characterised in relationship to either their morphology and surface chemical composition by Scanning Electron Microscopy coupled with Energy Dispersive X-rays spectroscopy (SEM-EDX), or their water absorption and mechanical properties (resistance to material abrasion). The results obtained showed that all the dispersions were nanometrically structured and their application succeeded in recovering the mechanical properties of the painting or graffito layers, not altering their permeability to water and keeping perfectly the wall transpiration. However, the dispersions constituted of the nanoparticles obtained via a synthesis able to control size and shape of the Ca(OH)₂ particles resulted in a better performance in situ, even if the differences found by SAXS and TEM were slight.