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[EN] The oblique collisions between two axisymmetric disks moving on a flat horizontal surface are described in terms of impact modeling based on the assumption that normal and tangential restitution mechanisms operate independently of friction. Describing these mechanisms in terms of the usual Coulomb formulation, the model allows for an interpretation of some ¿anomalous¿ experimental data reported in the literature. These experimental data, corresponding to the variation of the coefficients of friction and tangential restitution with the impact angle, remained unexplained in classic formulations, are understood within the framework of the independent friction-restitution closure. Experimental data for metallic coins are in agreement with that formulation, including rolling friction effects.

[EN] The voltammetry of immobilized particles (VIMP) is applied to describe the solid state electrochemistry of brass. This methodology, which involves sampling at the nanogram level, is applied to discriminate mints/authorities producing different Roman monetary emissions covering since the Republic (88 BCE) to Domitianus (55-96 CE) Upon attachment to graphite electrodes in contact with aqueous acetate buffer at pH 4.75, well defined voltarnmetric responses were obtained centered on Cu- and Zn-localized signals whose intensity can be correlated to EMP data, being sensitive to the contents of Zn (15-30 wt.%) and Sn (0.01-1.1 wt.%). Voltammetric data, combined with ATR-FTIR and FIB-PESEM/EDS, yield information on the structure of the metal patina and permit to characterize different monetary emissions being able, in the case of Augustus' sestertii, to discriminate between the productions from different monetary authorities.

[EN] The voltammetry of immobilized particles methodology (VIMP) is used to characterize the composition of artificial patinas on copper. The voltammetric response of carbonate-, nitrate-, chloride-, sulfate-, and sulfide-based patinas is described using sub-microsamples attached to graphite electrodes in contact with aqueous acetate buffer. Patina-characteristic voltammetric profiles are obtained for the different artificial patinas that can be recognized using the generalized Tafel analysis of the voltammetric curves. VIMP data could also provide layer-by-layer information about composition and compactness/crystallinity of the patinas for which a simplified theoretical modeling is presented.

[EN] The pigments were important in the funerary customs of the ancient Maya. They could be introduced as an offering inside the tombs or burials, and were also used to wrap the dead bodies, as if it were a funeral shroud. In the tombs and burials of royalty and high social classes the use of pigments for this purpose is well documented, and physicochemical studies are focused on their identification. This scientific contribution shows the results obtained when analyzing two reddish pigmenting materials from the grave goods of the tomb 19 of the archaeological site of Rio Azul, (Guatemalan Department of Peten), using a multi-technique approach including microscopy, diffraction, spectroscopic, electrochemical and chromatographic techniques. The results have enabled the identification of the inorganic and organic materials composing these pigmenting materials found in a ceramic posthumous offering dish and further discussion mainly has been focused on the geological source of the inorganic materials and the possible origin of the organic matter accompanying these two pigmenting materials.

[EN] The degradation of laboratory oil paint film specimens containing indigo and Prussian blue pigments and pictorial samples from the Sant Francesc de Paula painting exhibited in the Tomas Balvey Arxiu Museum (Cardedeu (Catalonia), Spain) has been studied by voltammetry of immobilized particles. This technique, combined with light microscopy, scanning electron microscopy-energy dispersive X-ray analysis, nanoindentation-atomic force microscopy, attenuated total reflectance-Fourier-transform infrared spectroscopy and gas chromatography-mass spectroscopy techniques permits the proposal of a dual scheme for the degradation of the pigments when naturally aged and submitted to accelerated UVA aging. Under conditions of moderate temperature, humidity and natural illumination, and low gradients of these parameters, Prussian blue acts as a radical scavenger moderating the production of reactive oxygen species produced in the oil binding medium by the action of ultraviolet radiation, resulting in the formation, in the solid state, of the solid-solution, {KFeIII[Fe-II(CN)(6)]}(x){Fe-III[Fe-III(CN)(6)]}(1-x), known as Berlin green, which then promotes the formation of indigo adducts with radicals. In several localized areas of the Sant Francesc de Paula paint showing strong degradation, Prussian blue acts as a promoter of the indigo oxidation to isatin, thus resulting in a considerable chromatic shift.

[ES] Uno de los retos que aborda el Laboratorio de Restauración del Museu de Prehistòria de València es el tratamiento de piezas que ya han sufrido en el pasado algún proceso de intervención. Por lo general se trata de materiales sobre los que se han empleado protecciones poco estables, refuerzos inadecuados o ¿rellenos¿ de faltantes aplicados de forma indiscriminada. En el presente artículo se presenta el estudio diagnóstico e intervención del cráneo y la mandíbula de un individuo femenino de Homo sapiens de la Cova del Parpalló (Gandia), correspondiente al Paleolítico superior. Esta pieza, tras su descubrimiento en 1930, fue llevada en 1935 al Laboratori d¿Arqueologia de la Universitat de Barcelona, donde fue reconstruida y restaurada no sin dificultad, añadiéndole refuerzos metálicos, adhesivos y reconstrucciones de ceras que claramente se presentaban ya envejecidas. Ha sido necesario, por tanto, llevar a cabo una nueva intervención y replantearse los criterios de actuación, avalados por los estudios analíticos pertinentes que han aportado información sobre la composición de los materiales empleados en la restauración anterior., [EN] One of the challenges of the Restoration Laboratory of the Museu de Prehistòria de València is the treatment of pieces that have suffered previous interventions in the past. This are generally materials that were restored with instable protections, inadequate reinforcements or missing fillers that were applied indiscriminately. This article shows the diagnostic study and intervention of the skull and mandible of a female Homo sapiens from `Cova del Parpalló¿ (Gandia), dated in the Upper Paleolithic. This piece, after its discovery in 1930, was taken in 1935 to the Laboratori d¿Arqueologia of the Universitat de Barcelona, where it was rebuilt and restored not without difficulty, adding metallic reinforcements, adhesives, and wax reconstructions which were clearly already aged. Therefore, it has been necessary to carry out a new intervention rethinking the performance criteria, backed by the relevant analytical studies that have provided information about the composition of the applied materials on the previous restoration.

[EN] The possibility of the electrochemical promotion of different solid-to-solid transformations including the performance of successive cation and anion insertion processes has been tested using malachite green, a triphenylmethane dye, in contact with aqueous NaCl electrolyte. Electrochemical data using the voltammetry of microparticles methodology reveal significant differences with the solution phase electrochemistry of the dye. Voltammetric data, combined with atomic force microscopy, focusing ion beam-field emission scanning electron microscopy, and high-resolution field emission scanning electron microscopy permit characterization of the oxidative dissolution, oxidation with anion insertion, reduction with cation insertion and reduction with anion issue processes, whose thermochemical aspects, involving separate ion and electron transport contributions, are discussed.

[ES] Las piezas numismáticas constituyen un importante porcentaje de las colecciones de los museos y una de las evidencias que con mayor frecuencia se encuentra en las excavaciones, tratándose de vestigios arqueológicos e históricos fundamentales para el estudio de diferentes aspectos de las sociedades pasadas. Para la investigación y la caracterización de estos materiales es necesario el empleo de técnicas analíticas no invasivas o nanoinvasivas que no comprometan la integridad de las monedas. En este trabajo se presentan los resultados obtenidos en la exploración de las capacidades de dos técnicas instrumentales analíticas, VIMP y FIB-FESEM-EDX, ambas de carácter nanoinvasivo, en colecciones numismáticas fabricadas en aleaciones en base cobre, escasamente empleadas en el estudio de patrimonio metálico hasta la fecha. Además, y en cada caso de estudio abordado, se han diseñado estrategias multitécnica que incluye el uso de SEM-EDX, espectroscopia FTIR, M.O., colorimetría y espectroscopia Raman. En una primera parte de la investigación se han desarrollado metodologías analíticas para la identificación y discriminación de aleaciones, productos de corrosión e intervenciones previas en tres colecciones de distinta titularidad y procedentes de diferentes ambientes. La primera colección, procede de un ambiente aéreo o atmosférico y es de titularidad privada, la colección Doménech-Francés. La segunda colección, procede de un ambiente de enterramiento y pertenece al Museu de Prehistòria de València. La última colección estudiada con esta finalidad procede de un ambiente subacuático, y pertenece al Museo Nacional de Arqueología Subacuática. En la segunda parte, el trabajo se centra en el desarrollo de una metodología innovadora basada en la técnica de electroquímica en estado sólido VIMP, que permite la discriminación entre cecas y el conocimiento de las técnicas de acuñación empleadas. Esta nueva metodología se ha implementado sobre dos casos de estudio diferentes: el prim, [CA] Las peces numismàtiques constitueixen un important percentatge de les col·leccions dels museus i una de les evidències que amb major freqüència es troba en les excavacions, i es tracta de vestigis arqueològics i històrics fonamentals per a l'estudi de diferents aspectes de les societats passades. Per a la investigació i la caracterització d'aquests materials és necessari l'ús de tècniques analítiques no invasives o nanoinvasives, que no comprometen la integritat de les monedes. En aquest treball es presenten els resultats obtinguts en l'exploració de les capacitats de dues tècniques instrumentals analítiques, VIMP i FIB-FESEM-EDX, ambdues de caràcter nanoinvasiu, en col·leccions numismàtiques fabricades en aliatges amb base de coure, escassament emprades en l'estudi del patrimoni metàl·lic fins avui. A més, en cada cas d'estudi abordat, s'han dissenyat estratègies multitècnica que inclouen l'ús de SEM-EDX, espectroscòpia FTIR, M.O., colorimetria i espectroscòpia Raman. En una primera part de la investigació s'han desenvolupat metodologies analítiques per a la identificació i discriminació d'aliatges, productes de corrosió i intervencions prèvies en tres col·leccions de diferent titularitat i procedents de diferents ambients. La primera col·lecció, procedeix d'un ambient aeri o atmosfèric i és de titularitat privada, la col·lecció Doménech-Francés. La segona col·lecció procedeix d'un ambient d'enterrament i pertany al Museu de Prehistòria de València. La última col·lecció estudiada amb aquesta finalitat procedeix d'un ambient subaqüàtic i pertany al Museu Nacional d'Arqueologia Subaqüàtica. En la segona part, el treball se centra en el desenvolupament d'una metodologia innovadora basada en la tècnica d'electroquímica en estat sòlid VIMP, que permet la discriminació entre seques i el coneixement de les tècniques d'encunyació emprades. Aquesta nova metodologia s'ha implementat sobre dos casos d'estudi diferents: el primer consisteix en una sèrie de maravedís encun, [EN] The numismatic pieces constitute an important part of the collections of the museums and one of the evidences that more frequently found in the excavations, being archaeological and historical vestiges fundamental for the study of severe aspects of the past societies. The use of non-invasive or nanoinvasive analytical techniques that do not compromise the integrity of the coins is essential for the investigation and characterization of these materials. This PhD presents the results obtained in the exploration of the capabilities of two nanoinvasive analytical instrumental techniques, VIMP and FIB-FESEM-EDX, in numismatic collections made of copper-based alloys, scarcely used in the study of heritage metallic so far. In addition, and in each study case discussed, multi-technical strategies have been designed that include the use of SEM-EDX, FTIR spectroscopy, O.M., colorimetry and Raman spectroscopy. In the first part of the investigation, analytical methodologies for the identification and discrimination of alloys, corrosion products and previous interventions in three collections of different ownership and coming from different environments have been developed. The first collection, comes from an air or atmospheric environment, is privately owned, the Doménech-Francés collection, the second collection, comes from a burial environment and belongs to the Museum of Prehistory of Valencia, and the last collection studied for this purpose, comes from an underwater environment and belongs to the National Museum of Underwater Archaeology. In the second part, the work focuses on the development of an innovate methodology based on the technique of solid-state electrochemistry VIMP that allows the discrimination between mints and the knowledge of the coinage techniques used. This new methodology has been implemented on two different case studies: the first consists of a series of maravedís coined between 1661 and 1664 by Philip IV, and the second, in a collection of ibe

[EN] A multi-technique strategy, including microscopy, spectroscopic and electrochemical techniques, is proposed to study thin corrosion layers that form on the surface of historic copper-based coins. An accurate characterisation of this external corrosion layer is important for selecting a suitable conservation and/or restoration treatment. For this purpose, a series of copper-based coins from different historical periods and provenances, which mainly exhibited atmospheric corrosion, was analysed. The morphology of the corrosion layer and the upper core of coins was studied in trenches done on coin surfaces with a focused ion beam gun, coupled to a field emission scanning electron microscope-X-ray microanalysis (FIB-FESEM-EDX). The X-ray microanalysis performed with FESEM-EDX on trenches allowed elemental composition profiles on the corrosion layer to be obtained. These results were complemented with the compositional data of the corrosion products provided by the voltammetry of immobilised microparticles (VIMP) and Fourier transform infrared spectroscopy (FTIR), and by studying visual appearance by optical microscopy and colorimetry. Cuprite and tenorite (the latter increased with coin age) were the main identified corrosion products, which were accompanied, to a lesser extent, by copper trihydroxychloride polymorphs. Interestingly, metal oxalates and metal-carboxylate complexes were identified on the corrosion layer of most coins. These unusual alteration products of copper-based coins were formed from the organic matter deposited on coin surfaces given their use when placed in circulation or by further manipulations of collectors.

This is the peer reviewed version of the following article: A. Doménech-Carbó, M. T. Doménech-Carbó, C. Álvarez-Romero, T. Pasíes, M. Buendía, Electroanalysis 2019, 31, 1164, which has been published in final form at https://doi.org/10.1002/elan.201900090. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving., [EN] The voltammetry of immobilized particles (VIMP) was applied for grouping a series of 86 Iberian coins nominally minted in the cities of Iltirta, Castulo and Obulco in the 2(th)-1(th) BCE period for which there are no chronological data. Using characteristic signatures for the reduction of cuprite, tenorite and lead corrosion products in the patina of the coins, voltammetric grouping of coins was proposed. Voltammetric data were found to be consistent with textural and compositional properties of the surface and subsurface of selected coins using FIB-FESEM-EDX. The obtained data confirmed a clear separation between the productions of Iltirta on one side, and those of Castulo and Obulco on the other side, indicating the possibility to establish a rough chronology for these productions.

[EN] The voltammetry of immobilized particles (VIMP) methodology was applied to discriminate the oil painting production of a series of seven painters/workshops that worked in Valencia (Spain) between ca. 1530 and ca. 1650. When submicrosamples used for cross-section FESEM/EDX analysis were attached to graphite electrodes in contact with aqueous acetate buffer, well-defined responses were obtained. The reductive processes of lead pigments (lead white and lead-tin yellow) overlapped those associated to the lead soaps and other species resulting from the pigment-oil binder interaction in the sample. Such responses, which are theoretically modeled, were sensitive to changes in paint type and dose and thus provided a painter/workshop-characteristic voltammetric response defining a usable electrochemical fingerprint for authorship assessments. (C) 2018 Elsevier Ltd. All rights reserved.

[EN] The presented study focuses on evaluating the efficiency of a gelatin-based product that incorporates a plasticizer (glycerol) and a biocide (citronella oil), proposed as an eco-friendly adhesive for polychrome decoration applied in different parts of the architectural complex of the Longshan Temple in Lukang (eighteenth century, Taiwan). Seven laboratory physico-chemical tests were performed: (a) viscosity measurement; (b) drying curves; (c) moisture content determination; (d) water vapor permeability test; (e) mechanical test; (f) adhesion test; (g) susceptibility to fungi colonization test, which provide information on the workability, water content and water barrier properties, as well as mechanical, adhesion, and the biocide properties of the proposed product. The obtained results indicate that the workability, mechanical and adhesive properties of the new adhesive are adequate. Permeability in polychromies is slightly reduced due to the additional barrier effect of the adhesive incorporated into the paint film. The efficiency of citronella oil for preventing the growth of fungus Aspergillus niger on paintings consolidated with the adhesive was also probed. In parallel to these laboratory trials, the micro-invasive tests carried out, using nanoindentation combined with atomic force microscopy (NI-AFM), provided direct evidence for the improvement in the mechanical properties induced by applying the new adhesive to the original polychromies.

El presente trabajo se centra en la evaluación de una selección de métodos de consolidación aplicados sobre fragmentos de madera carbonizada de origen arqueológico procedentes de Sagunto. En dicho estudio se han evaluado un total de seis consolidantes diferentes, Paraloid® B-72, Polivinil butyral, Cosmoloid® H 80 y Mowilith® en tres de sus formulaciones (20, 30 y 50). Estos consolidantes se han aplicado mediante inmersión e impregnación, sobre los fragmentos de madera carbonizada de origen arqueológico y sobre probetas realizadas en el laboratorio. Tras la aplicación de los consolidantes se han analizado propiedades ópticas como el brillo y el color sirviéndose del uso de espectrofotómetros. Se ha efectuado un estudio morfológico con microscopio estereoscópico a bajos aumentos y un estudio micromorfológico mediante Microscopía Electrónica de Barrido de Emisión de Campo (FESEM). También se han llevado a cabo ensayos para el análisis de las propiedades mecánicas y finalmente se ha estimado el grado de penetración de cada consolidante usando Espectroscopía Infrarroja por Transformada de Fourier (FTIR). El procesado y comparación de todos los datos obtenidos ha permitido determinar cómo interactúa cada consolidante con la madera carbonizada. Estos resultados ayudarán además a estimar la idoneidad del uso de los consolidantes estudiados para la conservación de fragmentos de madera carbonizada., The present work focuses on the evaluation of different methods of consolidation that have been applied on fragments of archaeological charcoal which coming from an archaeological site of Sagunto. In this research, 6 different consolidants have been evaluated, Paraloid® B-72, Polyvinyl butyral, Cosmoloid® H 80 and Mowilith® (20, 30 and 50). These consolidants have been applied by immersion and impregnation, on the archaeological fragments of charcoal and on pieces of charred wood made in the laboratory. After the application of consolidants, optical properties such as brightness and color have been analyzed using spectrophotometers. Morphological study was executed with stereoscopic microscopy and a micromorphological analysis using Electronic Emission Field Scanning Microscopy (FESEM). Mechanical properties have been also studied. Finally, the degree of penetration of each of the consolidants has been estimated by Infrared Spectroscopy by Fourier Transformation (FTIR). The analysis of results have determined their interaction with charcoal. These results allow to evaluate the suitability of the application of these consolidants for the conservation of archaeological charcoal fragments.

[EN] A set of ancient Antoninianus silver coins, dating back between 249 and 274¿A.D. and minted in Rome, Galliae, Orient and Ticinum, have been characterized. We use, for the first time, a combination of nano-invasive (focused ion beam-field emission scanning electron microscopy-X-ray microanalysis (FIB-FESEM-EDX), voltammetry of microparticles (VIMP)) and destructive techniques (scanning electron microscopy (SEM-EDX) and electron microprobe analysis (EMPA)) along with non-invasive, i.e., micro-Raman spectroscopy. The results revealed that, contrary to the extended belief, a complex Ag-Cu-Pb-Sn alloy was used. The use of alloys was common in the flourishing years of the Roman Empire. In the prosperous periods, Romans produced Ag-Cu alloys with relatively high silver content for the manufacture of both the external layers and inner nucleus of coins. This study also revealed that, although surface silvering processes were applied in different periods of crisis under the reign of Antoninii, even during crisis, Romans produced Antoninianus of high quality. Moreover, a first attempt to improve the silvering procedure using Hg-Ag amalgam has been identified.

[EN] The application of electrochemical techniques for obtaining analytical information of interest in the fields of archaeometry, conservation and restoration of cultural heritage goods is reviewed. Focused on voltammetry of immobilised particles and electrochemical impedance spectroscopy techniques, electrochemical measurements offer valuable information for identifying and quantifying components, tracing provenances and manufacturing techniques and provide new tools for authentication and dating.

Third European Conference on electrochemical techniques applied to the conservation of artworks. New Insights into the technical examination and conservation of metallic heritage artefacts (CEACA2017) is proposed as a forum for meeting and discussing addressed to students, researchers and professionals in the field of conservation and restoration of cultural goods and, in particular, of metal heritage, in which the most relevant works carried out by excellence teams in the last years in the national and European frame are presented in key-lectures. In parallel,CEACA2017 promotes the ex-change of knowledge and expertise trough a POSTER SESION OPEN, which is addressed to students,researchers and professionals who work in the field of conservation and restoration of metallic artefacts

[EN] A methodology for characterizing archeological gold embroidery threads based on two analytical techniques is described: Field emission scanning electron microscopy (FESEM-EDX) and voltammetry of immobilized microparticle (VIMP) methodologies. After the analysis of the chemical composition of the metallic foil, we analyze specific voltammetric features associated with the oxidation of gold in contact with aqueous H2SO4 and HCl electrolytes. Cyclic and square wave voltammetries (VMP) have been used to get information about the elemental composition and the corrosion products of the samples. AFM, FESEM-EDX, and FESEM-FIB-EDX methodologies complete the study and bring us closer to the composition of the alloys and the embroidery manufacture techniques. This technique actualizes the VIMP data and evidences the morphological and elemental differences between them; in particular, it is confirmed that Au-Ag-Cu alloys, with notably differences in Ag content depending on the provenance, were used.

This is the peer reviewed version of the following article: Doménech Carbó, Antonio, Scholz, Fritz , Domenech Carbo, Mª Teresa, Piquero-Cilla, Juan , Montoya, Noemí, Pasies -Oviedo, Trinidad, Gozalbes, Manuel , Melchor Montserrat, José Manuel , Oliver, Arturo . (2018). Dating of Archaeological Gold by Means of Solid State Electrochemistry.ChemElectroChem, 5, 15, 2113-2117. DOI: 10.1002/celc.201800435 , which has been published in final form at http://doi.org/10.1002/celc.201800435. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving, [EN] In archaeology and history of art, age determination is a fundamental analytical problem. While several techniques for age determination of various materials, like radiocarbon dating, are established, these methods cannot be applied for metals, for which new techniques have to be developed. For the first time a dating method for archaeological gold objects is described which is based on a corrosion clock and electrochemical measurements, using the voltammetry of immobilized particles. Samples are prepared by one touch' with a graphite pencil, only transferring a few nanograms of the archaeological gold. The method has been calibrated with the help of a series of well-documented gold specimen from different prehistory museums covering the last 2600years. Our results prove that this corrosion clock is going on a constant pace, practically independent of the environment, making it most attractive for applications in archaeometry.

[EN] The application of solid state electrochemistry techniques for the characterization and dating of leaded bronze objects is described. Characteristic voltammetric signatures of copper and lead corrosion products were used as markers of more or less prolonged corrosion periods. The proposed methodology was applied to samples from the Roman archaeological sites of Valeria (Spain) and Gadara (Jordan), Roman and medieval sites in Xativa (Spain), and modern statuary exhibited outdoors, on the campus of the Universitat Politecnica of Valencia, Spain, covering a time interval between the fourth to second century bc and the 20th century ad. For such samples, the ratio between the signals for copper and lead corrosion products decreased monotonically with the corrosion time. This variation was modelled on the basis of thermochemical and kinetic considerations, the experimental data being consistent with a potential rate law for the corrosion process.

[EN] The application of solid state electrochemistry techniques for dating archaeological strata using lead-containing bronze coins is described. The proposed methodology was applied to samples coming from the Roman archaeological site of Magna Mater Temple (Rome, Italy) occurring in different strata dating back between the second half and the end of the 4(th) century A.D. and the 20(th) century. The voltammetric signatures of copper and lead corrosion products in contact with aqueous acetate buffer, as well as the catalytic effects produced on the hydrogen evolution reaction, were used for establishing the age of different strata and dating coins belonging to unknown age. Voltammetric data were consistent with a theoretical approximation based on a potential rate law for the corrosion process.

[EN] Application of electrochemical impedance measurements to microparticulate deposits of copper corrosion products attached to graphite electrodes in contact with 0.10 M aqueous HClO4 electrolyte is described. The impedance measurements were sensitive to the applied potential and the amount of solid sample and were modeled taking into account the contribution of the uncovered base electrode. Several pairs of circuit elements provide monotonic variations which are able to characterize different corrosion compounds regardless the amount of microparticulate solid on the electrode. Application to a set of archaeological samples from the archaeological Roman site of Gadara (Jordan, 4th century AD) permitted to establish a grouping of such samples suggesting different provenances/manufacturing techniques.

[EN] A series of 20 denarii from Boleslaus the Brave (992-1025) and Mieszko II Lambert (1025-1034), corresponding to the beginning of the Polish state were studied using the voltammetry of immobilized particles (VIMP) methodology. VIMP experiments, applied to nanosamples of the corrosion layers of the coins in contact with aqueous acetate buffer, provided well-defined responses mainly corresponding to the corrosion products of copper and lead. Such voltammetric responses, combined with X-ray fluorescence (XRF) spectroscopy experiments performed on the same set of coins, and complemented by focusing ion beam-field emission scanning electron microscope (FIB-FESEM) on silver coins from the 19th century, supported the hypothesis that two different metal sources were used in the former historical period and suggested that the coins were produced in three different mints. (C) 2016 Elsevier B.V. All rights reserve.

El presente estudio pretende poner de manifiesto la manera de trabajar del pintor valenciano Vicente Requena (1556-h.1605) tomando como ejemplo una obra inédita de su producción, concretamente una tabla con la representación de San Cristóbal de Licia. A nivel estilístico, esta obra reúne todos aquellos aspectos esenciales que caracterizaron su pintura, lo que permite confirmar y justificar su autoría. Se sabe que Vicente Requena fue un pintor que transitó entre el romanismo joanesco y la pintura reformada implantada en Valencia a finales del siglo XVI por Juan Sariñena, concibiéndose como el vínculo más temprano entre la pintura escurialense y la autóctona. Además, su trayectoria artística también vino marcada por la herencia del estilo paterno, ya que fue el primero de los hijos de Gaspar Requena, un pintor de renombre en su época que estuvo al frente de un prolífico taller donde debió formarse y participar en numerosos encargos. Desde un punto de vista más experimental, el examen técnico y analítico de esta tabla ha permitido confirmar la metodología de trabajo empleada y los materiales constitutivos del soporte y los estratos pictóricos, lo que supone una aportación muy importante de cara a futuras investigaciones. Aunque es evidente que a través del estudio de una única pintura no se puede resumir la forma de trabajar de un artista, la práctica inexistencia de información publicada que ofrezca datos de carácter científico-técnico relativos a obras de la producción pictórica de Vicente Requena, ha hecho imposible establecer comparativas y ampliar los estudios sobre los materiales, técnicas y procedimientos utilizados por este pintor.

Los objetos metálicos, y en particular, las colecciones numismáticas, han sido el objeto de estudio de numerosas investigaciones arqueométricas centradas en el conocimiento de las sociedades del pasado, ya que de éstos es posible obtener una gran cantidad de información relativa a los usos y desarrollo tecnológico de esas civilizaciones a través de su procedencia, el proceso de manufactura o las materias primas empleadas. Las técnicas de análisis aplicadas para este fin han ido evolucionando con el tiempo, de forma que, actualmente, además del estudio metalográfico, se dispone de un amplio abanico de técnicas instrumentales que proporcionan información acerca de la composición, estructura y morfología del objeto metálico. En este trabajo se ha explorado las posibilidades de un nuevo método de análisis de colecciones numismáticas basado en el uso del Microscopio Electrónico de Barrido de Emisión de Campo con Haz de Iones Focalizado y Microanálisis de Rayos X (FESEM-FIB-EDX). Entre las ventajas que ofrece esta técnica, aplicada por primera vez en el estudio de objetos de metal arqueológico, está su carácter mínimamente invasivo para las piezas ya que no requiere toma de muestra y la alteración producida en el objeto se sitúa en la escala nanoscópica.

Egg (the whole, the yolk or the white) is a natural product used since ancient times as tempera painting medium mainly in Europe and the Mediterranean Basin countries. In addition, egg is a complex multicomponent microstructured system susceptible of being influenced by the pigments that compose the paints, as well as a source of nutrient susceptible of biodeterioration. Modifying effect of artists' pigments on the binding medium as well as, the microbial biodeterioration are responsible for changes in the structure and composition of the binding medium and, consequently, on the physico-chemical properties of the paint. For this purpose, analytical techniques such as Fourier transform infrared spectroscopy - attenuated total reflection (FTIR-ATR) was used for the chemical characterization, Field emission scanning microscopy (FESEM) and Atomic force microscopy - nanoindentation (AFM-nanoindentation) were run for morphological and mechanical characterization of the deterioration processes resulted from the pigment-binder interactions involved in tempera painting. On the other hand, the current research report the application of the voltammetry of microparticles (VMP), complemented with FTIR-ATR, FESEM and AFM-nanoindentation techniques to monitor the deterioration of a series of tempera reconstructed model paint specimens under the action of different biological agents. This methodology would be of application for identifying the type of biological agent causing deterioration of painting, which is an important problem affecting cultural heritage. The analysis of biodeterioration processes is complicated by the fact that the action of microorganisms can affect both pigment and binding media. The deterioration of pictorial specimens by Acremonium chrysogenum, Aspergillus niger, Mucor rouxii, Penicillium chrysogenum and Trichoderma pseudokoningii fungi and Arthrobacter oxydans, Bacillus amyloliquefaciens and Streptomyces cellulofans bacteria was tested using sample-modif, El huevo (entero, yema o clara) es un producto natural utilizado desde la antigüedad como medio aglutinante en la pintura al temple, principalmente en Europa y los países de la cuenca mediterránea. Además, el huevo es un complejo sistema multicomponente microestructurado susceptible de ser alterado por los pigmentos que componen las pinturas, así como fuente de nutrientes susceptible de biodeterioro. El efecto de los pigmentos sobre el medio aglutinante, así como el biodeterioro microbiano son responsables de cambios en la estructura y composición del medio aglutinante y, por consiguiente, en las propiedades fisicoquímicas de la pintura. Es por esto que, se utilizaron técnicas analíticas como la Espectroscopía Infrarroja por Transformada de Fourier en modo Reflexión Total Atenuada (FTIR-ATR), para la caracterización química de los procesos de deterioro resultantes de las interacciones pigmento-aglutinante en la pintura al temple. Así mismo, se utilizó Microscopía Electrónica de Emisión de Barrido (FESEM) para el estudio morfológico de las muestras, y para el estudio de las propiedades mecánicas Microscopía de Fuerza Atómica en modo Nanoindentación (AFM-nanoindentación). Por otro lado, la presente investigación propone el uso de la Voltamperometría de Micropartículas (VMP), en conjunto con otras técnicas de análisis como FTIR-ATR, FESEM y AFM-nanoindentación para el estudio del biodeterioro producido por hongos y bacterias sobre una serie muestras pictóricas sometidas. El estudio de las alteraciones causadas por el biodeterioro es complicado por el hecho de que la acción de los microorganismos puede afectar tanto al pigmento como al medio aglutinante. Para esto, se prepararon una serie de muestras de pinturas al temple y emulsión que fueron inoculadas con los hongos Acremonium chrysogenum, Aspergillus niger, Mucor rouxii, Penicillium chrysogenum, y Trichoderma pseudokoningii, y las bacterias Arthrobacter oxydans, Bacillus amyloliquefaciens y Streptomyces cellulofans., L'ou (sencer, rovell o clara) és un producte natural utilitzat des de l'antiguitat com a mitjà aglutinant en la pintura al tremp, principalment a Europa i els països de la conca mediterrània. A més, l'ou és un complex sistema multicomponent MICROESTRUCTURAT susceptible de ser alterat pels pigments que componen les pintures, així com a font de nutrients susceptible de biodeterioració. L'efecte dels pigments sobre el medi aglutinant, així com el BIODETERIORI microbià són responsables de canvis en l'estructura i composició del medi aglutinant i, per tant, en les propietats fisicoquímiques de la pintura. És per això que, es van utilitzar tècniques analítiques com l'Espectroscòpia Infraroja per Transformada de Fourier en mode Reflexió Total Atenuada (FTIR-ATR), per a la caracterització química dels processos de deteriorament resultants de les interaccions pigment-aglutinant en la pintura al tremp. Així mateix, es va utilitzar Microscòpia Electrònica d'emissió de Rastreig (FESEM) per a l'estudi morfològic de les mostres, i per a l'estudi de les propietats mecàniques Microscòpia de Força Atòmica en mode Nanoindentació (AFM-nanoindentació). D'altra banda, la present investigació proposa l'ús de la Voltamperometría de Micropartícules (VMP), en conjunt amb altres tècniques d'anàlisi, com FTIR-ATR, FESEM i AFM-nanoindentació per a l'estudi de l'biodeterioració produït per fongs i bacteris sobre una sèrie de mostres pictòriques sotmeses. L'estudi de les alteracions causades pel biodeteriori és complicat pel fet que l'acció dels microorganismes pot afectar tant el pigment com al medi aglutinant. Per això, es van preparar una sèrie de mostres de pintures al tremp i emulsió que van ser inoculades amb els fongs Acremonium chrysogenum, Aspergillus niger, Mucor rouxii, Penicillium chrysogenum, i Trichoderma pseudokoningii i els bacteris Arthrobacter oxydans, Bacillus amyloliquefaciens i Streptomyces cellulofans. L'estudi voltamperomètric es va realitzar utilitzant electrodes de grafi

Este libro está editado con ocasión de las Segundas Jornadas de Investigación Emergente en Conservación y Restauración de Patrimonio (EMERGE 2016) celebradas en Valencia el 26 de octubre de 2016.Esta Conferencia ha sido organizada por el Instituto Universitario de Restauración del Patrimonio, el Departamento de Conservación y Restauración de Bienes Culturales,la Facultad de Bellas Artes,el Máster Universitario en Conservación del Patrimonio Arquitectónico de la Escuela Técnica Superior de Arquitectura y el Vicerrectorado de Alumnado y Extensión Universitaria de la Universitat Politècnica de València

[EN] It is reported the application of the voltammetry of microparticles (VMP), complemented with attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and field emission scanning electron microscopy (FESEM) techniques, to monitor the deterioration of verdigris pictorial specimens under the action of different biological agents. This methodology would be of application for identifying the type of biological agent causing deterioration of paintings, which is an important problem affecting cultural heritage. The analysis of biodeterioration processes is complicated by the fact that the action of microorganisms can affect both pigment and binding media. The deterioration of pictorial specimens combining verdigris with egg and egg-linseed oil binders by Penicillium chrysogenum, Aspergillus niger, Acremonium chrysogenum, Trychoderma pseudokoningi and Mucor rouxii fungi and Bacillus amyloliquefaciens, Arthrobacter oxydans and Streptomyces cellulofans bacteria were tested using sample-modified graphite electrodes immersed into aqueous electrolytes. A model is presented to describe the involved electrochemistry resulting in specific voltammetric features for the electrochemical reduction of verdigris associated to the proteinaceous and lipidic fractions of the binders. The experimental results and model proposed have been discussed and compared with those previously obtained for cadmium yellow reconstructed paint film specimens.

[EN] Field emission scanning electron microscopy (FESEM-EDX) with focused ion beam (FIB-FESEM-EDX) and cyclic and square wave voltammetry of microparticles methodologies (VMP) had been used for characterizing archaeological golden threads from some Roman and Islamic archaeological sites in Valencia. There are non or minimally invasive techniques to obtain morfological information and elemental composition in the case of FESEM-EDX and FIB-FESEM-EDX and to make species studies in the case of CV and SQWV. The analytical studies expose the presence of different type of gold, silver and copper alloys, La técnica de microscopía electrónica de barrido por emisión de campo combinada con microanálisis de rayos X (FESEM-EDX) y con haz de iones enfocados (FIB-FESEM-EDX) junto con voltametría cíclica (CV) y de onda cuadrada (SQWV) se han utilizado para caracterizar un conjunto de muestras de hilos de oro procedentes de excavaciones de la ciudad de Valencia datados en los períodos Romano e Islámico. Se trata de técnicas no invasivas que permiten obtener información morfológica y de composición elemental en el caso de FESEM-EDX y FIB-FESEM-EDX y efectuar estudios de especiación en el caso de CV y SQWV. Los análisis llevados a cabo con estas metodologías analíticas han puesto de manifiesto diferentes tipos de aleación de oro, plata y cobre., [CA] La tècnica de microscòpia d’escombratge per emissió de camp combinada amb la microanàlisi de rajos X (FESEM-EDX) i amb ions enfocats (FIB-FESEM-EDX), es conjuga amb la voltamperometria cíclica (CV) i d’ona quadrada (SQWV) per utilitzar-se per a caracteritzar un conjunt de mostres de fils daurats provinents d’excavacions de la ciutat de València datats als períodes Romà i Islàmic. Es tracta de tècniques no o mínimament invasives que permeten obtenir informació morfològica i de composició elemental en el cas de FESEM-EDX i FIB-FESEM-EDX, i efectuar estudis d’especiació al cas de CV i SQWV. Les anàlisis realitzats amb aquestes metodologies analítiques han posat de manifest la presència de diferents tipus d’aliatges d’or, argent i coure.

[EN] An electrochemical methodology for discriminating monetary emissions, a recurrent problem in much archaeological studies, is introduced. The method is based on the record of voltammetric signatures of cuprite and tenorite corrosion products in the patina using a minimally invasive nanosampling following the voltammetry of immobilized particles methodology. A model for the depth variation of voltammetric electrochemical parameters characterizing the composition of the corrosion patinas is presented. This model permits to rationalize electrochemical data and discriminate different monetary emissions. The application of this technique, corroborated by electrochemical impedance spectroscopy (EIS) and focusing ion beam-field emission scanning electron microscopy (FIB-FESEM-EDX), to a series of 10 cash copper coins produced around the Kuang Hsu and Hsuan Tung last Chinese emperors permits to discern different provincial mints and reveals that the monetary unification developed in this period was not uniform.

This is the peer reviewed version of the following article: Montoya, Noemí, Montagna, Elena, Lee, Yu, Domenech Carbo, Mª Teresa, Doménech Carbó, Antonio. (2017). Raman spectroscopy characterization of 10-cash productions from the late Chinese emperors to the Republic.Journal of Raman Spectroscopy, 48, 10, 1337-1345. DOI: 10.1002/jrs.5218 , which has been published in final form at http://doi.org/10.1002/jrs.5218. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving., [EN] The use of Raman spectroscopy for discriminating monetary emissions, a recurrent problem in much archaeological studies, is described. The method involves the record of Raman signatures of tenorite and crystalline and defective cuprite in the patina based on the idea that subtle, mint-characteristic variations in the composition and metallography of the base metal during the manufacturing process are reflected in the variation in depth of the composition and crystallinity of the corrosion patina. The technique was applied to a series of 10-cash copper coins produced around the transition between the Kuang Hsu and Hsuan Tung last Chinese emperors and the first Republic whose averaged composition was 95 +/- 1% wt Cu plus 5 +/- 1% wt Zn often accompanied by traces of Sn and Pb. Raman data, corroborated by focusing ion beam-field emission scanning electron microscopy and voltammetry of immobilized particles measurements, suggested the possibility of discerning between different provincial and regular unified currency productions.

This is the peer reviewed version of the following article: Doménech Carbó, A.; Domenech Carbo, MT.; Álvarez-Romero, C.; Montoya, N.; Pasies-Oviedo, T.; Buendía Ortuño, MDM. (2017). Electrochemical Characterization of Coinage Techniques the 17(th) Century: The maravedis Case. Electroanalysis. 29(9):2008-2018. doi:10.1002/elan.201700326, which has been published in final form at http://doi.org/10.1002/elan.201700326. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.", [EN] The voltammetry of immobilized particles (VIMP) methodology was applied to the discrimination of Spanish maravedis produced in 10 different mints between 1661 and 1664 using characteristic signatures for the reduction of cuprite and tenorite in the patina of the coins and catalytic effects on the hydrogen evolution reaction (HER). The variation of the apparent tenorite/cuprite ratio with depth was fitted to potential laws differing from one mint to another for A Coruna, Burgos, Cordoba, Cuenca, Granada, Madrid, Trujillo, Segovia, Sevilla and Valladolid coins. Electrochemical data permitted to detect the changes in the composition (with lowering of the silver content) and manufacturing technique (from hammer to mill) occurring in this historical period.

[EN] A method for identifying vegetal species in wooden objects using microextraction-assisted voltammetry of microparticles is described. The proposed methodology, aimed at facilitating tasks of patrimony conservation, is based on the recording of the voltammetric response of microparticulate films of compounds resulting from microextraction with organic solvents (ethanol, acetone, and chloroform) of micro- or sub-microsamples of wood in contact with aqueous buffers. Upon application of bivariate and multivariate chemometric techniques, the obtained voltammetric responses led us to identify different taxonomic groups from the characteristic voltammetric profiles. Application to a series of samples of wooden objects of cultural heritage of different European and American provenances dated to ca. 375¿ 350 BC and to historical periods, namely 14th and 17¿19th centuries, is described

[EN] Researchers have related the manufacturing technique of plasters and stucco in the Maya area with their period of production but not with their architectural function. In this paper, we establish a relationship between those three features (manufacturing technique, age, and architectural function) in the plasters of the Maya site of Dzibanche in southern Quintana Roo. Dzibanche has abundant remains of stuccos and plasters found mainly in three buildings (Plaza Pom, Pequena Acropolis, and Structure 2). We used thin sections, SEM and XRD, and archaeomagnetic dating processes. The pictorial layer of Structure 2 was the earliest (AD 274-316 and the stuccoes and plasters of the other two buildings were dated to the Middle Classic (AD 422-531), but we obtained different archaeomagnetic dates for the red pigment layers found in the buildings of the Pequena Acropolis and thus we were able to determine their chronological order of construction. The raw materials and proportions were carefully chosen to fulfil the mechanical necessities of the architectonic function: different proportions were found in plasters of floors, in the external walls, and inside the buildings; differences between earlier and later plasters were also detected.

[EN] A web-based database of voltammograms is presented for characterizing artists' pigments and corrosion products of ceramic, stone and metal objects by means of the voltammetry of immobilized particles methodology. Description of the website and the database is provided. Voltammograms are, in most cases, accompanied by scanning electron microphotographs, X-ray spectra, infrared spectra acquired in attenuated total reflectance Fourier transform infrared spectroscopy mode (ATR-FTIR) and diffuse reflectance spectra in the UV-Vis-region. For illustrating the usefulness of the database two case studies involving identification of pigments and a case study describing deterioration of an archaeological metallic object are presented. (C) 2016 Elsevier B.V. All rights reserved.

[EN] The application of the voltammetry of microparticles methodology to the study of gildings in paintings and architectural ornaments is described. Nanosamples from pieces from different churches of the Comunitat Valenciana (Spain) covering since the fifteenth century until nowadays were studied upon attachment to graphite electrodes in contact with aqueous HCl and H2SO4 electrolytes. Electrochemical measurements, combined with field emission scanning electron microscopy X-ray microanalysis (FESEM-EDX) and atomic force microscopy (AFM) data, denoted that a common manufacturing technique was used with minimal variations along time. The relationship between specific voltammetric features associated to bulk gold and active surface sites, however, changed monotonically with time, thus suggesting the possibility of age monitoring.

[EN] The characterization of corrosion products in leaded bronze based on the voltammetry of immobilized particles methodology is described. Voltammetric data, supported by Fourier transform infra-red spectroscopy, field emission scanning electron microscopy-energy dispersive X-ray microanalysis (FESEM-EDX) and scanning electrochemical microscopy (SECM) allow the identification of copper and lead corrosion materials. The mutual influence of such products is modeled upon considering uncompensated ohmic drops in the Tafel analysis of the rising portion of the respective voltammetric signals for their electrochemical reduction.

[EN] The present research suggests, on one hand, optimizing a multi-technical method for the characterization of organic compounds and traditional lime mortars to use in monumental buildings of antiquity. To illustrate the effectiveness of this methodology it has been applied to a study case, the stucco from mural painting of Maya culture (Ancient Mesoamerica), which has been chosen by the need to continue studying the composition of preparation layers of these stuccos. There are two reasons for this choice: the first one is that knowledge of materials and of execution techniques of these surfaces is providing new data to understand the technological complexity of this culture; and the second one is based on the fact that just this type of research will allow us to know with certainty how these preparation layers were made and, this way, ensure the correct interventions of conservation and restoration. From these considerations, the study conducted establishes a methodological approach that comes from the specialized literature search of geographical and cultural context, the physical (geology and climatology) and biological environment (flora and vegetation) from Yucatan Peninsula (Mexico), getting theoretical knowledge necessary to deal with a detailed description and characterization of the raw materials from the geological environment that were used in the manufacture of the preparation layers from Maya mural painting. The method continues with the use of instrumental analysis techniques such as optical microscopy (OM), polarizing optical microscopy (POM), infrared Fourier transform spectroscopy (FT-IR), x-ray diffraction (XRD), scanning electron microscopy-x-ray microanalysis (SEM-EDX), x-ray microdiffraction (µ-XRD), transmission electron microscopy (TEM) and the optimization of instrumental techniques for analyzing organic compounds, such as gas chromatography/mass spectrometry (GC/MS). On the other hand, the current researches tend to reinforce the idea of i, [ES] La presente investigación propone, de un lado, la optimización de un método multitécnica para la caracterización de componentes orgánicos y morteros de cal tradicionales en construcciones monumentales de la antigüedad. Para ejemplificar la eficacia de esta metodología, se ha aplicado a un caso de estudio, los estucos de la pintura mural de la cultura maya (Antigua Mesoamérica), que ha sido elegido por la necesidad de seguir estudiando la composición de las capas de preparación de estos estucos. Existen dos motivos para esta elección: el primero es que el conocimiento de los materiales y de las técnicas de ejecución de estas superficies está aportando nuevos datos para comprender la complejidad tecnológica de esta cultura; y el segundo se basa en que tan sólo este tipo de investigaciones nos permitirán conocer con certeza como se realizaron estas capas de preparación y, de este modo, garantizar las correctas intervenciones de conservación-restauración. A partir de estas consideraciones, el estudio llevado a cabo establece un planteamiento metodológico que parte de la búsqueda de bibliografía especializada del contexto geográfico, del marco cultural, del medio físico (la geología y la climatología) y biológico (la flora y la vegetación) de la Península de Yucatán (México), consiguiendo el conocimiento teórico necesario para afrontar una descripción y caracterización ajustada de las materias primas del entorno geológico que se usaron en la manufactura de las capas de preparación de la pintura mural maya. El método continua con el aprovechamiento de técnicas instrumentales de análisis, como la microscopia óptica (MO), la microscopia óptica de luz polarizada (MOP), la espectroscopia infrarroja por transformada de Fourier (FT-IR), la difracción de rayos-x (DRX), la microscopia electrónica de barrido-microanálisis de rayos-x (SEM-EDX), la microdifracción de rayos-x (µ-DRX), la microscopía electrónica de transmisión (TEM) y la optimización de técnicas instrumentales av, [CA] La present investigació proposa, per una banda, l'optimització d'un mètode multitècnica per a la caracterització de components orgànics i morters de calç tradicionals en construccions monumentals de l'antiguitat. Com exemplicació de l'eficàcia, aquesta metodologia s'ha aplicat a un cas d'estudi, els estucs de la pintura mural de la cultura maia (Antiga Mesoamèrica). L'elecció d'aquest cas d'estudi està motivada per la necessitat de seguir estudiant la composició de las capes de preparació d'aquests estucs. Existeixen dos motius per a això: el primer és que el coneixement dels materials i de les tècniques d'execució d'aquestes superfícies està aportant noves dades per a comprendre la complexitat tecnològica d'aquesta cultura i el segon és que, sols aquesta classe d'investigacions ens permetran conèixer amb certesa com foren realitzades aquestes capes de preparació, i en conseqüència, garantir correctes intervencions de conservació-restauració. A partir d'aquestes consideracions, l'estudi portat a terme estableix un plantejament metodològic que parteix de la recerca de bibliografia especialitzada, aconseguint un coneixement teòric, del context geogràfic, del marc cultural, del medi físic (la geologia i la climatologia) i biològic (la flora i la vegetació) de la Península de Yucatán (Mèxic), necessari per a afrontar la correcta descripció i caracterització de les matèries primeres de l'entorn geològic, utilitzades en la manufactura de las capes de preparació de la pintura mural maia i conseqüentment, per a la correcta interpretació dels estucs procedents dels assentaments arqueològics de les Terres Baixes Maies del Nord (Península de Yucatán, Mèxic) estudiats, mitjançant l'aprofitament de tècniques instrumentals d'anàlisis, com la microscòpia òptica (MO), la microscòpia òptica de llum polaritzada (MOP), l'espectroscòpia infraroja per transformada de Fourier (FT-IR), la difracció de raigs-x (DRX) i la microscòpia electrònica de rastreig-microanàlisis de raigs-x (SE