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Os materiais metálicos do século XX apresentam propriedades físicas e de resistência à corrosão com interesse para a arquitetura, tendo neste âmbito uma ampla gama de aplicações. Contudo, estão sujeitos a degradação, frequentemente associada às condições de utilização e ambiente de exposição, cujas consequências vão desde alterações estéticas à perda de funcionalidade dos componentes e estruturas em que se encontram aplicados. Neste artigo, descreve-se o comportamento típico de vários materiais metálicos correntemente usados nas edificações, quando usados em componentes de arquitetura exterior, correlacionando-o com a corrosividade ambiental e modos de utilização. O conjunto de informação reunida teve como objetivo contribuir para uma seleção adequada dos metais a aplicar numa determinada obra. Metallic materials of the 20th century exhibit physical properties and corrosion resistance with interest for architecture, having in this scope a wide range of applications. However, they are subject to degradation, often associated with the conditions of use and environmental exposure. The consequences of which, range from aesthetic changes to the loss of functionality of the respective components. In this article, we describe the typical behavior of several metallic materials commonly used in buildings, when used in exterior architectural components, correlating it with atmospheric corrosivity and ways of use. The set of information gathered aimed to contribute for an adequate selection of the metals apply in future works.

This study deals with the identification of the degradation products present on some Byzantine glasses coming from an archaeological excavation in Northern Tunisia. The main purpose of the present investigation is the identification of the products and the characterization of surface altered points, namely iridescent and black patinas, which are present on some selected glasses. Non-destructive techniques such as XPS (X-ray Photoelectron Spectroscopy), SEM-EDS (Scanning Electron Microscopy coupled with Energy Dispersive Spectroscopy), ATR-FTIR (Attenuated Total Reflection-Fourier Infrared Spectroscopy) and LA-ICP-MS (Laser-Ablation Inductively Coupled Plasma-Mass Spectrometry) are here exploited. SEM-EDS was employed to ascertain the morphological structure and the chemical composition of various points, apparently different, on the glass surfaces. Small area XPS was performed for identifying the elements present on the sample surface, for determining their chemical state and for establishing the atomic composition of the morphologically different regions. LA-ICP-MS was exploited to determine the chemical composition as far as the trace elements are concerned. The presence of iridescent patinas and of encrustations has been highlighted on the glass surfaces in correspondence to the altered areas: iridescent patinas are due to the fact that the glasses are depleted in alkali and alkaline earths. The incrustations resulted due to the presence of calcium carbonates, and/or oxyhydroxides. In one case sulfides were also detected by SEM.

The Royal Artillery Factory of Seville in Spain originated from pre-existing private bronzefoundries dating from the 16th century. The paper analyses the stratigraphy of wall claddingin the areas traditionally known as the‘Old Foundry’and the‘New Foundry’, through itscharacterization by optical microscopy, scanning electron microscopy with energy-dispersive X-ray spectrometry (SEM-EDX), micro-X-rayfluorescence (μ-XRF) and micro-X-ray diffraction (μ-XRD), in order to analyse the metal deposits that have accumulated sincethe 17th century. The data obtained allowed the verification of the available historiographicalinformation and the location of the original bronze smelting furnaces. The analysis of patinasdeposited on the overlapping layers of lime also confirmed that neither the raw materials northe composition of the alloys used presented any substantial changes

This paper reports an unusual green pigment, brochantite (Cu4(SO4)(OH)6), on 16th-century Portuguese-Flemish paintings, attributed to the Master Frei Carlos workshop. This green mineral is usually identified as an impurity or alteration product in the green pigments verdigris (Cu(CH3COO)2nCu(OH)2) or malachite (CuCO3 Cu(OH)2). However, after thorough investigation with a broad range of analytical techniques, it became clear that, in this case, brochantite was applied as a pigment. The abundance, pigment granulometry, and pigment morphology suggest intentional use by this Portuguese-Flemish Master as a natural pigment rather than its accidental use as an alteration product. This seems to be a distinguishable feature to other painters (Flemish and Portuguese) working in Portugal at the beginning of the 16th century.The multi-analytical study of these easel paintings was first performed by physical imaging techniques and material characterization was carried out by optical microscopy, micro-Fourier-transform infrared-spectroscopy, micro-Raman spectroscopy, scanning electron microscopy coupled with energy dispersive X-ray spectrometry, and micro-X-ray diffraction analysis (XRD).

El objeto principal del presente trabajo es determinar la estructura de los estratos que componen el revestimiento del paramento de las zonas identificadas en la Fábrica de Artillería de Sevilla como “fundición vieja” y “fundición nueva” y realizar la caracterización química de los mismos con la finalidad concreta de identificar los posibles depósitos metálicos que pudieran haberse acumulado durante la actividad fabril de fundición llevada a cabo en el edificio desde finales del siglo XVI hasta el XX (Sobrino 2011). Hay que señalar que las posibles pátinas han sido sucesivamente ocultadas mediante el pintado de los paramentos, de ahí que la serie estratigráfica acumulada a lo largo del tiempo corresponda a una secuencia alterna (Barbero, 2013).Las muestras fueron evaluadas inicialmente mediante microscopía óptica para la determinación de los estratos existentes. Mediante microfluorescencia de rayos X y microscopía electrónica se identificaron las partículas que contenían metales y se determinó su composición química (Berthold, 2009). Este análisis confirmó la hipótesis de la presencia de elementos metálicos pesados, destacando especialmente la presencia de hierro, habiéndose detectado también en las distintas muestras en proporciones minoritarias, aunque relevantes (cobre, cinc y, en casos aislados, plomo y níquel). Todos ellos responden a su posible presencia en los materiales utilizados en la fundición The main objective of the present work is to determine the structure of the strata composing the coating of the walls in the areas identified in the Seville Artillery Factory as “old foundry” and “new foundry” and perform the chemical characterization of the same with the specific purpose of identifying the possible metallic deposits that could have accumulated during the factory foundry activity carried out in the building from the end of the 16th century until the XX (Sobrino 2011). It should be noted that the painting of the walls has successively hid the possible patinas; hence the stratigraphic series accumulated over time corresponds to an alternate sequence (Barbero, 2013).The samples were initially evaluated by optical microscopy to determine the existing strata. By means of X-ray microfluorescence and electron microscopy, the particles containing metals were identified and their chemical composition determined (Berthold, 2009). This analysis confirmed the hypothesis of the presence of heavy metal elements, especially the presence of iron, and also in the different samples, in minor proportions, although relevant (copper, zinc and, in isolated cases, lead and nickel). All of them respond to their possible presence in the materials used in the foundry

International audience; In order for the traits associated with aerial dissemination to be positively selected through evolution, microorganisms that survive atmospheric transport must multiply in some habitat that they have accessed via this transport. Surprisingly little is known about the rates of successful colonization of new-found habitats by the diverse range of microorganisms in the atmosphere. Most examples come from studies of the microbial ecology of extreme oligotrophic habitats with low microbial loads or of the epidemiology of plant diseases caused by very host-specific pathogens. The patterns that emerge from these studies suggest that successful colonization of new-found habitats depends on the interplay of resource availability, the weight of microbial competition, and the specialization of microorganisms to very particular niches. We suggest new experimental approaches to further elucidate the frequency of habitat colonization and invasion by microorganisms traveling in the atmosphere.

The present work analyze the protective state of patinas developed on bronzes of different composition, which are the base alloy of outdoor exposed monuments in Buenos Aires city. The results of in situ measurements and X-ray energy dispersion (EDX) analyses, carried out on powder samples of different sectors and metallic micro-samples of pre-selected zones, were used to select the best intervention criteria to be applied on two historical-national monuments: Adolfo Alsina and El Cristo Central monuments. It could be established that chemical composition and morphology of the samples, as well as their colour and texture, are directly related to the exposure grade of the selected area of the monument, to the effect of pollutants and atmospheric agents. Bearing in mind these results, and those of measurements of temporal variation of the corrosion potential by means of a technique applied in situ, sectors« intervention was proposed, maintaining the protective patinas and respecting the state in which the works are at the present time, in reference to the moment of their outdoor exposure.

We have conducted controlled laboratory experiments using a series of bronze alloys exposed to frequent, repeated wet and dry cycles, to simulate frequent acid rain exposure and study the resultant corrosion processes in bronze artifacts exposed to an outdoor urban environment. To simulate rainwater and condensation, a spray chamber for the corrosion tests was assembled, which delivered homogeneous vapor diffusion and drop deposition. Three bi-component bronzes, with 3%, 7% and 20% tin content, were subjected to seven days of controlled wet and dry cycles, and analyzed at precise intervals. Electrochemical impedance spectroscopy and spectrocolorimetry results were combined to show the different phases of corrosion. The patinas on all three samples at the end of the exposure period were studied with scanning electron microscopy to show the morphology of corrosion products; they were also analyzed by X-ray diffraction. The sample containing 7% tin produces a patina that is unstable and frequently dissolved. Partial patina dissolution also occurs during exposure for the 3% tin sample, but the effects are less pronounced. Because it reacts the least with the environment, the 20% tin sample demonstrates intermediate behavior (between the 7% and the 3% tin samples). However, the patina is less protective than the 3% tin sample patina.

We investigated the decayed historical church window glasses of two Catalonian churches, both under Mediterranean climate. Glass surfaces were studied by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and X-ray diffraction (XRD). Their chemical composition was determined by wavelength-dispersive spectrometry (WDS) microprobe analysis. The biodiversity was investigated by molecular methods: DNA extraction from glass, amplification by PCR targeting the16S rRNA and ITS regions, and fingerprint analyses by denaturing gradient gel electrophoresis (DGGE). Clone libraries containing either PCR fragments of the bacterial 16S rDNA or the fungal ITS regions were screened by DGGE. Clone inserts were sequenced and compared with the EMBL database. Similarity values ranged from 89 to 100% to known bacteria and fungi. Biological activity in both sites was evidenced in the form of orange patinas, bio-pitting, and mineral precipitation. Analyses revealed complex bacterial communities consisting of members of the phyla Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria. Fungi showed less diversity than bacteria, and species of the genera Cladosporium and Phoma were dominant. The detected Actinobacteria and fungi may be responsible for the observed bio-pitting phenomenon. Moreover, some of the detected bacteria are known for their mineral precipitation capabilities. Sequence results also showed similarities with bacteria commonly found on deteriorated stone monuments, supporting the idea that medieval stained glass biodeterioration in the Mediterranean area shows a pattern comparable to that on stone. © 2012 Elsevier Ltd., This study was financed by the Austrian Science Fund (FWF) project “Hertha-Firnberg T137.” G. Piñar is currently financed by the Austrian Science Fund (FWF) project “Elise-Richter V194-B20.”

This article reports on a compositional investigation of stone patinas: thin colored layers applied for protective and/or aesthetic purposes on architectural or sculptural substrates of cultural heritage. The analysis and classification of patinas provide important information of historic and artistic interest, as their composition reflects local practices, the availabilities of different materials, and the development of technological knowledge during specific historical periods. Model patinas fabricated according to traditional procedures and applied onto limestone, and a historic patina sample from the main façade of the San Blas Monastery in Lerma (a village in the province of Burgos, Spain), were analyzed by laser-induced fluorescence and Fourier transform Raman spectroscopy. The results obtained demonstrate the ability of these two analytical techniques to identify the key components of each formulation and those of the reaction products which result from the chemical and mineralogical transformations that occur during aging, as well as to provide information that can aid the classification of different types of patinas., This work has been funded by the Madrid Regional Government project Geomateriales (S2009/Mat-1629) and by the Ministerio de Ciencia e Innovación under projects CTQ2010-15680 and CONSOLIDER CSD2007-00058.

We investigated the decayed historical church window glasses of two Catalonian churches, both under Mediterranean climate. Glass surfaces were studied by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and X-ray diffraction (XRD). Their chemical composition was determined by wavelength-dispersive spectrometry (WDS) microprobe analysis. The biodiversity was investigated by molecular methods: DNA extraction from glass, amplification by PCR targeting the16S rRNA and ITS regions, and fingerprint analyses by denaturing gradient gel electrophoresis (DGGE). Clone libraries containing either PCR fragments of the bacterial 16S rDNA or the fungal ITS regions were screened by DGGE. Clone inserts were sequenced and compared with the EMBL database. Similarity values ranged from 89 to 100% to known bacteria and fungi. Biological activity in both sites was evidenced in the form of orange patinas, bio-pitting, and mineral precipitation. Analyses revealed complex bacterial communities consisting of members of the phyla Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria. Fungi showed less diversity than bacteria, and species of the genera Cladosporium and Phoma were dominant. The detected Actinobacteria and fungi may be responsible for the observed bio-pitting phenomenon. Moreover, some of the detected bacteria are known for their mineral precipitation capabilities. Sequence results also showed similarities with bacteria commonly found on deteriorated stone monuments, supporting the idea that medieval stained glass biodeterioration in the Mediterranean area shows a pattern comparable to that on stone., Highlights ► Na-rich and K-rich (or K–Ca-rich) glasses were distinguished and investigated. ► Biological activity evidenced orange patinas, bio-pitting and mineral precipitation. ► Bacteria belonged to Proteobacteria, Bacteroidetes, Firmicutes and Actinobacteria. ► Fungi were less diverse and belonged to species of the genus Cladosporium and Phoma. ► The microorganisms detected were related to the observed biodeterioration phenomena.

Les paysages désertiques et leur évolution sont souvent bien décrits par les géomorphologues. Plus rarement, les travaux portent sur les processus élémentaires qui engendrent des microformes d’accumulation ou d’ablation : dépôts fluviatiles, concrétionnements, patines, vernis, vermiculures, cailloux à facettes, etc. On décrit ici les principales formes en analysant les catégories de processus. Certains ont déjà été interprétés, d’autres restent encore à comprendre. The desert landscapes and their evolution are often well described by geomorphologists. Less often, the research focuses on the elementary processes which generate accumulation or ablation microforms: alluvial deposits, concretion formations, patinas, varnishes, vermiculations, faceted stones, etc. Here we describe the main forms by analysing the process categories. Some have already been interpreted, others still remain to be understood.

En el año 2004 el Ministerio de Fomento llevó a cabo el proyecto de «Restauración integral de la Torre de la catedral de Murcia (cuerpos 1º,2º,3º e interior del 4º)» que entre otras actuaciones, tenía prevista la intervención en la superficie original de cantería, cubierta por diversas pátinas de diversa heterogeneidad e irregularidad, que no pudo completar en esta fase de la restauración, dada la naturaleza de las mismas. Región de Murcia. Universidad Politécnica de Cartagena. Campus Mare Nostrum. Forum Unesco. Escuela de Arquitectura e Ingeniería de Edificación. (ARQUIDE). Universidad de Murcia. Facultad de Letras. Ayuntamiento de Cartagena Lorquimur. Restauración y construcción. Restauralia Cartago. Grupo Entorno

As esculturas de exterior em liga de cobre, sem a aplicação de medidas de protecção, podem mostrar aceleração da degradação devido à corrosão, agravada pelo aumento da poluição atmosférica associado ao desenvolvimento industrial e social do último século. Da corrosão resulta a alteração cromática da superfície das estátuas, com a formação de patinas de cor verde e preta, cujas características definem níveis de risco de degradação e, consequentemente, o tipo de intervenção a que a escultura deverá ser submetida para a sua conservação. Neste artigo abordam-se os processos de corrosão mais comuns em estátuas de ligas de cobre expostas no exterior e descreve-se a formação, composição e estrutura das patinas resultantes dessa corrosão. Referem-se ainda alguns aspectos sobre a conservação deste tipo de obras de arte. Copper alloy sculptures subjected to the atmospheric exposure without appropriate corrosion protective measures show accelerated degradation due to corrosion, enhanced by the rise in atmospheric pollution resulting from industrial and social development of the last century. Corrosion causes chromatic changes on surface with formation of black and green patinas, whose characteristics define levels of risk of degradation, therefore the type of conservation needed for its preservation. In this paper the atmospheric corrosion process of copper alloy statues is focused, describing patinas formation, constitution and structure. Additionally, some aspects related with conservation of this type of monument are referred.

Publicado en el libro "Ciencia, Tecnología y Sociedad" dentro del programa Maternas financiado por la Comunidad de Madrid, en colaboración con la Asociación Restauradores sin Fronteras. Editado por el Ayuntamiento de San Sebastián de los Reyes, Madrid, [EN] This paper focuses on patinas, considering them as thin films or coverings on the surface of building materials result of the application of past treatments with protective and/or aesthetical purposes. A methodology for the study of patinas is presented, including their first detection on a building, the aspects to consider regarding location in façades, height, colour, continuity, etc, as well as the analytical techniques to use for their characterization, mainly microscopic and microanalysis techniques, being the most useful the portable ones. Minerals usually found in patinas are calcite, gypsum, calcium oxalates and phosphates, iron oxides and hydroxides and silicates. These minerals account for the different original constituents of patinas. Besides this mineral fraction, an important organic fraction is frequently found, which accounts for the organic additives added to the mixture. The existence of patinas on the surface of stones usually contributes to protect them, their lack resulting on the accelerated ageing of the stone. Their knowledge will contribute to avoid their indiscriminate remotion, and to protect and preserve them, not only as a sustainable protective treatment but also as an important element of the building history of our heritage., [ES] Este estudio se centra en pátinas, considerándolas como finas o cubiertas en la superficie de materiales de construcción, resultantes de la aplicación de antiguos tratamientos con fines protectores y/o estéticos. Se presenta una metodología para el estudio de pátinas, incluyendo su primera detección en un edificio, los aspectos a considerar con respecto a su ubicación en las fachadas, la altura, el color, la continuidad, etc, así como las técnicas analíticas a utilizar para su caracterización, principalmente técnicas microscópicas y de microanálisis, siendo las más útiles las técnicas portátiles. Los minerales que encontramos habitualmente en las patinas son calcita, yeso, oxalatos y fosfatos cálcicos, óxidos e hidróxidos de hierro y silicatos. Estos minerales tienen relación con los diferentes componentes originales de patinas. Además de esta fracción mineral, se encuentra, con frecuencia, una importante fracción orgánica, relacionada con los aditivos orgánicos añadidos a la mezcla. La existencia de pátinas en la superficie de la piedra, por lo general contribuye a su protección; su pérdida o ausencia deriva en el envejecimiento acelerado de la piedra. Su conocimiento contribuirá a evitar su eliminación indiscriminada, y a su protección y preservación, no sólo como una técnica de protección sostenible, sino también como un elemento importante de la historia de la construcción de nuestro patrimonio., Ayuntamiento de San Sebastián de los Reyes

Surface layers grown by oxidation or corrosion onto copper-based objects belonging to the cultural heritage are often rich of important information concerning the object original aspect, the abandonment circumstances and the conservation state. They are often of complex nature and structure. Their complete analysis is difficult because it is submitted to severe preservation constraints.This thesis concerns high temperature oxidation layers and intentional antique patina grown on the surface of copper-base alloys.Non-destructive analysis methods and experimental devices best adapted to that problematic have been specifically developed, mostly based on ion beam analyses.High temperature oxidation of the copper-tin system have been comprehensively studied: nature of the layers, growth kinetic and reaction mechanisms. A model have been proposed which takes into account the experimental observations and the inhibiting effect of tin addition.The antique intentional patina obtained through chemical surface treatment done by the craftsmen in order to modify the surface colour and aspect of the metal have been also studied. A corpus of objects from national museums, produced during a period of 2000 years from the antique Egypt to the Roman Empire, have been analysed.These analyses allowed to sensibly increase the literature data on this kind of objects and this kind of practice. Laboratory analogues have been elaborated through the experimentation of various reported recipes. The results on archaeological objects and laboratory experimentation lead to significant progress in the knowledge of these particular oxide layers, and also in the field of the history of techniques and stylistic history in the Mediterranean antiquity.; Les couches d'oxydation et de corrosion présentes à la surface des alliages cuivreux d'objets du patrimoine culturel sont souvent très riches d'informations. Elles peuvent renseigner sur l'aspect d'origine de l'objet, sur les causes d'abandon et sur l'état de conservation. Elles sont souvent de structures et de natures très complexes et leur analyse est très délicate car elle est soumise à des contraintes sévères de préservation de l'objet.Nous nous sommes intéressés aux couches provenant d'oxydations à haute température et aux patines intentionnelles antiques.Nous avons développé les méthodes analytiques non destructives et les dispositifs expérimentaux les plus adaptés à ces problématiques en nous basant principalement sur les analyses par faisceau d'ions.L'oxydation à haute température du système cuivre-étain a été étudiée de manière approfondie, tant au niveau de la nature des couches, des cinétiques de croissance que des mécanismes réactionnels. Nous avons proposé un modèle tenant compte de tous les résultats expérimentaux que nous avons obtenus, mettant en évidence le rôle inhibiteur de l'étain.Nous avons également étudié les patines intentionnelles antiques qui sont le résultats de traitements chimiques effectués par l'artisan pour modifier l'aspect et la couleur du matériau métallique. Pour cela nous avons analysé un corpus d'objet provenant des collections de divers musées nationaux, s'étalant de l'Egypte Antique à l'Empire romain.Ces analyses ont permis d'augmenter significativement les données présentes dans la littérature sur ce type d'objets et sur ces techniques. Elles ont permis la fabrication d'analogues de laboratoire en expérimentant différentes recettes présentes dans la littérature. Les résultats des analyses d'objets et de ces expérimentations ont permis des avancées dans la connaissance de ce type de couches d'oxyde très particulières, mais aussi dans le domaine de l'histoire des techniques et stylistique dans l'Antiquité méditerranéenne.

Six protective coating systems, commonly used in conservation practice, have been tested both on polished bronze coupons and on selected areas of a bronze statue in similar exposure conditions. Patinas have been characterised both on outdoor exposure on the monument and as developed on the polished bronze coupons. Electrochemical Impedance Spectroscopy measurements, using a specially designed contact probe, have been conducted on coupons and in situ on the bronze statue. Data for the first two years of weathering in a marine environment are reported. The coating performance on the polished coupons and on the corroded bronze monument is discussed.

Summarization: A hybrid consolidant with high affinity to carbonaceous substrates was synthesized by adding synthesized nano-hydroxyapatite into TEOS sol, while for the first time, amylamine (CH3(CH2)4NH2) was used as a surfactant, providing an efficient means of protecting gels from cracking by reducing the capillary pressure. Amylamine is characterized by a short chain amine molecule, therefore, the amphiphilicity increased by the hydrophilic functional groups and hydrophobic tail groups without causing the formation of any amphiphilic molecule clusters. The hydroxyapatite was selected on the grounds of the weathering resistance often encountered in well-preserved monument surfaces (patinas) and attributed to the combination of hydroxyapatite, with calcium oxalate, and silica. The role of hydroxyapatite and amylamine in the silica structure was further examined by comparing the synthesized consolidant with other nanocomposites containing TEOS, TEOS and hydroxyapatite, and TEOS and amylamine as basic reagents. The synthesized products have been characterized and evaluated for their effectiveness as strengthening agents on limestone that is widely used in the historic and modern architectural structures in the Mediterranean basin. Generally, the nanocomposite-treated stone demonstrated an improvement in hygric properties, drilling resistance, and tensile strength due to the crack-free structure of the nanocomposite. Appearing in: Advanced Materials for the Conservation of Stone