74 research outputs found
Multiple-scan voltammetry and OCP: Archaeometric tools for dating archaeological bronzes
[EN] The application of a multiple-scan strategy to nanosamples taken from 18 cross-sections of Bronze Age arms and armour, as well as two Roman coins using two solid-state electrochemical techniques, the voltammetry of immobilized microparticles (VIMP) and open circuit potential measurements (OCP) is described. The voltammetric responses in contact with aqueous acetate buffer can be attributed to the reduction of cuprite with variable degree of compaction and crystallinity revealing significant differences in the gradient of such properties with depth. Such differences are also revealed by "dry" OCP measurements connecting points in the cross section near and separated from the corrosion layer. The voltammetric study of the metallographic samples of the bronze objects shows correlation with the age of the objects, respectively the period of their deposition. We discuss also (potential) influence of different factors on the VIMP and OCP measurements, such as deposition context (soil, water), chemical composition of the copper alloys, and microstructural features (ascast, annealed, work-hardened), and how to overcome these issues.Project CTQ2017-85317-C2-1-P, supported with Ministerio de Economia, Industria y Competitividad (MINECO), Fondo Europeo de Desarrollo Regional (ERDF) and Agencia Estatal de Investigacion (AEI), is gratefully acknowledged.Doménech-Carbó, A.; Mödlinger, M.; Domenech Carbo, MT. (2021). Multiple-scan voltammetry and OCP: Archaeometric tools for dating archaeological bronzes. Journal of Electroanalytical Chemistry. 893:1-9. https://doi.org/10.1016/j.jelechem.2021.115336S1989
Cation and anion electrochemically assisted solid-state transformations of malachite green
[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.Financial support from the Project CTQ2017-85317-C2-1-P (Ministerio de Economia, Industria y Competitividad (MINECO), Fondo Europeo de Desarrollo Regional (ERDF) and Agencia Estatal de Investigacion (AEI)), is gratefully acknowledged.Doménech-Carbó, A.; Dias, D.; Domenech Carbo, MT. (2020). Cation and anion electrochemically assisted solid-state transformations of malachite green. Physical Chemistry Chemical Physics. 22(3):1502-1510. https://doi.org/10.1039/c9cp05835dS1502151022
Aplicación de la técnica de microscopia electrónica de barrido de emisión de campo con haz de iones focalizado-microanálisis de rayos x a colecciones numismáticas
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.La presente investigación está financiada con el
proyecto I+D: “Aplicación de las técnicas
nanoelectroquimicas y biotecnologías en el estudio y
conservación del patrimonio en metal” Referencia:
CTQ2014-53736-C3 cofinanciado con fondos FEDER
adscrito al Programa estatal de fomento de la
investigación científica y técnica de excelencia,
subprograma estatal de generación del conocimiento,
MINECO. (2015-2017). Los autores agradecen la
colaboración de Dr. José Luis Moya y Manuel Planes,
técnicos responsables del Servicio de Microscopía
Electrónica de la Universitat Politècnica de València.Álvarez Romero, C.; Domenech Carbo, MT. (2017). Aplicación de la técnica de microscopia electrónica de barrido de emisión de campo con haz de iones focalizado-microanálisis de rayos x a colecciones numismáticas. Arché. (11 - 12):65-70. http://hdl.handle.net/10251/101195657011 - 1
Electroanalytical techniques in archaeological and art conservation
[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.Financial support from the Spanish MINECO Projects CTQ2014-53736-C3-1-P and CTQ2014-53736-C3-2-P which are also supported with ERDF funds.Doménech Carbó, A.; Domenech Carbo, MT. (2018). Electroanalytical techniques in archaeological and art conservation. Pure and Applied Chemistry. 90(3):447-461. https://doi.org/10.1515/pac-2017-0508S44746190
Characterization of additives of PVAc and acrylic waterborne dispersions and paints by analytical Py-GC-MS and Py-Silylation-GC-MS
[EN] Commercial formulations of poly(vinyl acetate) (PVAc) and acrylic dispersions and paints commonly used by artists include a number of additives such as surfactants, coalescing agents, defoamers and thickeners, which are designed for improving shelf-life, as well as chemical and physical properties of the resulting product. Recent studies have shown that additives present in paints play an important role in the alteration processes undergone by the painting during ageing and further in cleaning tasks planed in conservation interventions. However, the identification of additives is a difficult task due to the elusive character of these substances present at low concentration in the paint.
In this context, a four-step approach is proposed that includes analysis of paint samples together with analysis of their water extracted products by pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) and pyrolysis-silylation-gas chromatography-mass spectrometry (Py-silylation-GC-MS). This analytical strategy enables a better characterization of common additives present in commercial PVAc and acrylic paints and dispersions. In particular, the analysis of water soluble extracts, which are mainly composed by paint additives, avoids the interference of the major polymer pyrolizates. Experimental conditions concerning sample preparation and instrumental working conditions of both Py-GC techniques are optimized.
Both acrylic and PVAc paints presented poly(ethylene oxide) (POE) type fragments dominating the background of their pyrograms, especially when derivatized by means of hexamethyldisilazane (HMDS). For the first time, additives such as alkyl sulfate and alkyl ether sulfate with C-10 and C-12 alkyl chains, poly(ethoxylate) fatty alcohol and octylphenyl poly(ethoxylate) surfactants were identified, as well as polyvinyl alcohol (PVOH) protective colloids, hydrophobically modified ethoxylated urethane (HEUR) thickeners an defoamers. Their major fragments and corresponding mass spectra are discussed. (C) 2015 Elsevier B.V. All rights reserved.Financial support from the MINECO Projects CTQ2011-28079-CO3-01 and CTQ2014-53736-C3-1-P, which are supported with ERDF funds, is gratefully acknowledged.Silva, MF.; Domenech Carbo, MT.; Osete Cortina, L. (2015). Characterization of additives of PVAc and acrylic waterborne dispersions and paints by analytical Py-GC-MS and Py-Silylation-GC-MS. Journal of Analytical and Applied Pyrolysis. 113:606-620. https://doi.org/10.1016/j.jaap.2015.04.011S60662011
Dating archaeological copper using electrochemical impedance spectroscopy. Comparison with voltammetry of microparticles dating
[EN] A methodology for dating copper/bronze archaeological objects aged under atmospheric environments using electrochemical impedance spectroscopy (EIS) is described. The method is based on the measurement of resistance associated to the growth of corrosion layers in EIS recorded upon immersion of the pieces in mineral water and applying a bias potential for the reduction of dissolved oxygen. Theoretical expressions for the time variation of such resistance following a potential rate law are presented. Equivalent expressions are derived and applied for estimating the variation of the tenorite/cuprite ratio from their specific voltammetric signals using voltammetry of microparticles data. Calibration curves were constructed from a set of well-documented coins.Financial support from the MEC Projects CTQ2011-28079-CO3-01 and 02 and CTQ2014-53736-C3-2-P which are supported with ERDF funds is gratefully acknowledged.Domenech Carbo, A.; Capelo, S.; Piquero-Cilla, J.; Domenech Carbo, MT.; Barrio, J.; Fuentes, A.; Al Sekhaneh, W. (2016). Dating archaeological copper using electrochemical impedance spectroscopy. Comparison with voltammetry of microparticles dating. Materials and Corrosion. 67(2):120-129. https://doi.org/10.1002/maco.201408048S120129672Friedman, I., & Smith, R. L. (1960). Part I, The Development of the Method. American Antiquity, 25(4), 476-493. doi:10.2307/276634Reich, S., Leitus, G., & Shalev, S. (2003). Measurement of corrosion content of archaeological lead artifacts by their Meissner response in the superconducting state; a new dating method. New Journal of Physics, 5, 99-99. doi:10.1088/1367-2630/5/1/399Scholz, F., Schröder, U., Meyer, S., Brainina, K. Z., Zakhachuk, N. F., Sobolev, N. V., & Kozmenko, O. A. (1995). The electrochemical response of radiation defects of non-conducting materials An electrochemical access to age determinations. Journal of Electroanalytical Chemistry, 385(1), 139-142. doi:10.1016/0022-0728(94)03840-yDoménech-Carbó, A., Labuda, J., & Scholz, F. (2012). Electroanalytical chemistry for the analysis of solids: Characterization and classification (IUPAC Technical Report). Pure and Applied Chemistry, 85(3), 609-631. doi:10.1351/pac-rep-11-11-13Doménech-Carbó, A., Doménech-Carbó, M. T., & Costa, V. (Eds.). (2009). Electrochemical Methods in Archaeometry, Conservation and Restoration. Monographs in Electrochemistry. doi:10.1007/978-3-540-92868-3Doménech-Carbó, A., Doménech-Carbó, M. T., & Peiró-Ronda, M. A. (2011). Dating Archeological Lead Artifacts from Measurement of the Corrosion Content Using the Voltammetry of Microparticles. Analytical Chemistry, 83(14), 5639-5644. doi:10.1021/ac200731qDoménech-Carbó, A., Doménech-Carbó, M. T., Capelo, S., Pasíes, T., & Martínez-Lázaro, I. (2014). Dating Archaeological Copper/Bronze Artifacts by Using the Voltammetry of Microparticles. Angewandte Chemie International Edition, 53(35), 9262-9266. doi:10.1002/anie.201404522Benarie, M., & Lipfert, F. L. (1986). A general corrosion function in terms of atmospheric pollutant concentrations and rain pH. Atmospheric Environment (1967), 20(10), 1947-1958. doi:10.1016/0004-6981(86)90336-7Strandberg, H. (1998). Reactions of copper patina compounds—II. influence of sodium chloride in the presence of some air pollutants. Atmospheric Environment, 32(20), 3521-3526. doi:10.1016/s1352-2310(98)00058-2Cano, E., Lafuente, D., & Bastidas, D. M. (2009). Use of EIS for the evaluation of the protective properties of coatings for metallic cultural heritage: a review. Journal of Solid State Electrochemistry, 14(3), 381-391. doi:10.1007/s10008-009-0902-6Hernandez-Escampa, M., Gonzalez, J., & Uruchurtu-Chavarin, J. (2009). Electrochemical assessment of the restoration and conservation of a heavily corroded archaeological iron artifact. Journal of Applied Electrochemistry, 40(2), 345-356. doi:10.1007/s10800-009-0003-3Angelini, E., Grassini, S., Parvis, M., & Zucchi, F. (2011). An in situ investigation of the corrosion behaviour of a weathering steel work of art. Surface and Interface Analysis, 44(8), 942-946. doi:10.1002/sia.3842Grassini, S., Angelini, E., Parvis, M., Bouchar, M., Dillmann, P., & Neff, D. (2013). An in situ corrosion study of Middle Ages wrought iron bar chains in the Amiens Cathedral. Applied Physics A, 113(4), 971-979. doi:10.1007/s00339-013-7724-1Doménech-Carbó, A., Doménech-Carbó, M. T., Peiró-Ronda, M. A., Martínez-Lázaro, I., & Barrio-Martín, J. (2012). Application of the voltammetry of microparticles for dating archaeological lead using polarization curves and electrochemical impedance spectroscopy. Journal of Solid State Electrochemistry, 16(7), 2349-2356. doi:10.1007/s10008-012-1668-9Degrigny, C., Guibert, G., Ramseyer, S., Rapp, G., & Tarchini, A. (2009). Use of E corr vs time plots for the qualitative analysis of metallic elements from scientific and technical objects: the SPAMT Test Project. Journal of Solid State Electrochemistry, 14(3), 425-435. doi:10.1007/s10008-009-0890-6Souissi, N., Bousselmi, L., Khosrof, S., & Triki, E. (2004). Voltammetric behaviour of an archeaological bronze alloy in aqueous chloride media. Materials and Corrosion, 55(4), 284-292. doi:10.1002/maco.200303719Souissi, N., Triki, E., Bousselmi, L., & Khosrof, S. (2006). Comparaison between archaeological and artificially aged bronze interfaces. Materials and Corrosion, 57(10), 794-799. doi:10.1002/maco.200503974Souissi, N., & Triki, E. (2009). Characterization of ethnographic copper corrosion. Materials and Corrosion, 60(4), 262-268. doi:10.1002/maco.200805068Mata, A. L., Salta, M. M. L., Neto, M. M. M., Mendonça, M. H., & Fonseca, I. T. E. (2010). Characterization of two Roman coins from an archaeological site in Portugal. Materials and Corrosion, 61(3), 205-210. doi:10.1002/maco.200905284Feliu, S., Morcillo, M., & Feliu, S. (1993). The prediction of atmospheric corrosion from meteorological and pollution parameters—II. Long-term forecasts. Corrosion Science, 34(3), 415-422. doi:10.1016/0010-938x(93)90113-uSpence, J. W., Haynie, F. H., Lipfert, F. W., Cramer, S. D., & McDonald, L. G. (1992). Atmospheric Corrosion Model for Galvanized Steel Structures. CORROSION, 48(12), 1009-1019. doi:10.5006/1.3315903Bhattacharjee, S., Roy, N., Dey, A. K., & Banerjee, M. K. (1993). Statistical appraisal of the atmospheric corrosion of mild steel. Corrosion Science, 34(4), 573-581. doi:10.1016/0010-938x(93)90273-jKobus, J. (2000). Long-term atmospheric corrosion monitoring. Materials and Corrosion, 51(2), 104-108. doi:10.1002/(sici)1521-4176(200002)51:23.0.co;2-vBalasubramaniam, R., Laha, T., & Srivastava, A. (2004). Long term corrosion behaviour of copper in soil: A study of archaeological analogues. Materials and Corrosion, 55(3), 194-202. doi:10.1002/maco.200303723Natesan, M., Venkatachari, G., & Palaniswamy, N. (2006). Kinetics of atmospheric corrosion of mild steel, zinc, galvanized iron and aluminium at 10 exposure stations in India. Corrosion Science, 48(11), 3584-3608. doi:10.1016/j.corsci.2006.02.006Doménech, A., Doménech-Carbó, M. T., Pasies, T., & del Carmen Bouzas, M. (2012). Modeling Corrosion of Archaeological Silver-Copper Coins Using the Voltammetry of Immobilized Particles. Electroanalysis, 24(10), 1945-1955. doi:10.1002/elan.201200252Rosas-Camacho, O., Uquidi-Macdonald, M., & Macdonald, D. D. (2009). Deterministic Modeling of the Corrosion of Low-Carbon Steel by Dissolved Carbon Dioxide and the Effect of Acetic Acid. I-Effect of Carbon Dioxide. doi:10.1149/1.3259806Macdonald, D., & Englehardt, G. (2010). The Point Defect Model for Bi-Layer Passive Films. doi:10.1149/1.3496427Sharifi-Asl, S., Taylor, M. L., Lu, Z., Engelhardt, G. R., Kursten, B., & Macdonald, D. D. (2013). Modeling of the electrochemical impedance spectroscopic behavior of passive iron using a genetic algorithm approach. Electrochimica Acta, 102, 161-173. doi:10.1016/j.electacta.2013.03.143Macdonald, D. D. (2011). The history of the Point Defect Model for the passive state: A brief review of film growth aspects. Electrochimica Acta, 56(4), 1761-1772. doi:10.1016/j.electacta.2010.11.005Doménech-Carbó, A., Lastras, M., Rodríguez, F., Cano, E., Piquero-Cilla, J., & Osete-Cortina, L. (2013). Monitoring stabilizing procedures of archaeological iron using electrochemical impedance spectroscopy. Journal of Solid State Electrochemistry, 18(2), 399-409. doi:10.1007/s10008-013-2232-yBlum, D., Leyffer, W., & Holze, R. (1996). Pencil-Leads as new electrodes for abrasive stripping voltammetry. Electroanalysis, 8(3), 296-297. doi:10.1002/elan.1140080317Doménech-Carbó, A., Doménech-Carbó, M. T., & Peiró-Ronda, Mªa. (2011). ‘One-Touch’ Voltammetry of Microparticles for the Identification of Corrosion Products in Archaeological Lead. Electroanalysis, 23(6), 1391-1400. doi:10.1002/elan.201000739Nair, M. T. ., Guerrero, L., Arenas, O. L., & Nair, P. . (1999). Chemically deposited copper oxide thin films: structural, optical and electrical characteristics. Applied Surface Science, 150(1-4), 143-151. doi:10.1016/s0169-4332(99)00239-1Scott, D. A. (1997). Copper compounds in metals and colorants: oxides and hydroxides. Studies in Conservation, 42(2), 93-100. doi:10.1179/sic.1997.42.2.93Doménech, A., Doménech-Carbó, M. T., & Martínez-Lázaro, I. (2010). Layer-by-layer identification of copper alteration products in metallic works of art using the voltammetry of microparticles. Analytica Chimica Acta, 680(1-2), 1-9. doi:10.1016/j.aca.2010.09.002Doménech, A., Doménech-Carbó, M. T., Pasies, T., & Bouzas, M. C. (2011). Application of Modified Tafel Analysis to the Identification of Corrosion Products on Archaeological Metals Using Voltammetry of Microparticles. Electroanalysis, 23(12), 2803-2812. doi:10.1002/elan.201100577Li, W. S., Cai, S. Q., & Luo, J. L. (2004). Chronopotentiometric Responses and Capacitance Behaviors of Passive Film Formed on Iron in Borate Buffer Solution. Journal of The Electrochemical Society, 151(4), B220. doi:10.1149/1.1667521Liu, W., Zhang, H., Qu, Z., Zhang, Y., & Li, J. (2009). Corrosion behavior of the steel used as a huge storage tank in seawater. Journal of Solid State Electrochemistry, 14(6), 965-973. doi:10.1007/s10008-009-0886-2Toledo-Matos, L. A., & Pech-Canul, M. A. (2010). Evolution of an iron passive film in a borate buffer solution (pH 8.4). Journal of Solid State Electrochemistry, 15(9), 1927-1934. doi:10.1007/s10008-010-1213-7Park, J.-J., & Pyun, S.-I. (2003). Analysis of impedance spectra of a pitted Inconel alloy 600 electrode in chloride ion-containing thiosulfate solution at temperatures of 298–573 K. Journal of Solid State Electrochemistry, 7(6), 380-388. doi:10.1007/s10008-002-0346-8Ibrahim, M. A., Pongkao, D., & Yoshimura, M. (2001). The electrochemical behavior and characterization of the anodic oxide film formed on titanium in NaOH solutions. Journal of Solid State Electrochemistry, 6(5), 341-350. doi:10.1007/s100080100229Xia, Z., Nanjo, H., Aizawa, T., Kanakubo, M., Fujimura, M., & Onagawa, J. (2007). Growth process of atomically flat anodic films on titanium under potentiostatical electrochemical treatment in H2SO4 solution. Surface Science, 601(22), 5133-5141. doi:10.1016/j.susc.2007.04.211Acevedo-Peña, P., Vázquez, G., Laverde, D., Pedraza-Rosas, J. E., & González, I. (2009). Influence of structural transformations over the electrochemical behavior of Ti anodic films grown in 0.1 M NaOH. Journal of Solid State Electrochemistry, 14(5), 757-767. doi:10.1007/s10008-009-0838-xFabregat-Santiago, F., Bisquert, J., Garcia-Belmonte, G., Boschloo, G., & Hagfeldt, A. (2005). Influence of electrolyte in transport and recombination in dye-sensitized solar cells studied by impedance spectroscopy. Solar Energy Materials and Solar Cells, 87(1-4), 117-131. doi:10.1016/j.solmat.2004.07.017Rubinstein, I. (1987). Electrochemical Impedance Analysis of Polyaniline Films on Electrodes. Journal of The Electrochemical Society, 134(12), 3078. doi:10.1149/1.2100343Lee, S.-J., & Pyun, S.-I. (2006). Assessment of corrosion resistance of surface-coated galvanized steel by analysis of the AC impedance spectra measured on the salt-spray-tested specimen. Journal of Solid State Electrochemistry, 11(6), 829-839. doi:10.1007/s10008-006-0229-5Doménech, A., Doménech-Carbó, M. T., & Edwards, H. G. M. (2008). Quantitation from Tafel Analysis in Solid-State Voltammetry. Application to the Study of Cobalt and Copper Pigments in Severely Damaged Frescoes. Analytical Chemistry, 80(8), 2704-2716. doi:10.1021/ac7024333Mora, N., Cano, E., Polo, J. L., Puente, J. M., & Bastidas, J. M. (2004). Corrosion protection properties of cerium layers formed on tinplate. Corrosion Science, 46(3), 563-578. doi:10.1016/s0010-938x(03)00171-9Bastidas, J. M., Polo, J. L., Cano, E., Torres, C. L., & Mora, N. (2000). Localised corrosion of highly alloyed stainless steels in an ammonium chloride and diethylamine chloride aqueous solution. Materials and Corrosion, 51(10), 712-718. doi:10.1002/1521-4176(200010)51:103.0.co;2-vXu, J., Huang, W., & McCreery, R. L. (1996). Isotope and surface preparation effects on alkaline dioxygen reduction at carbon electrodes. Journal of Electroanalytical Chemistry, 410(2), 235-242. doi:10.1016/0022-0728(96)04545-7Kuang, F., Zhang, D., Li, Y., Wan, Y., & Hou, B. (2008). Electrochemical impedance spectroscopy analysis for oxygen reduction reaction in 3.5% NaCl solution. Journal of Solid State Electrochemistry, 13(3), 385-390. doi:10.1007/s10008-008-0570-yChen, G., Waraksa, C. C., Cho, H., Macdonald, D. D., & Mallouka, T. E. (2003). EIS Studies of Porous Oxygen Electrodes with Discrete Particles. Journal of The Electrochemical Society, 150(9), E423. doi:10.1149/1.159472
Influence of plasticizer and biocide on the functional properties of gelatin-based adhesives used in painting consolidation
The study presented herein focuses on the influence of glycerol and citronella oil, added to gelatin dispersions as plasticizer and biocide, respectively, on the mechanical, water barrier and other functional properties of gelatin-based adhesives used in treatments of painting consolidation. For this purpose, ATR-FTIR spectroscopy, gas chromatography mass spectrometry, atomic force microscopy analyses combined with tensile, water vapour permeability, water content and water solubility tests were performed on gelatin films prepared by adding glycerol and citronella oil. These two products were chosen for their low toxicity and eco-friendly properties. The modification in the behaviour of gelatin-based adhesives as a result of addition of glycerol and citronella oil was evaluated on the basis of changes of the three-dimensional structure of the protein molecules due to their interaction with glycerol and citronella oil. All these data were provided by the analytical techniques. In a second step, stability of the proposed adhesive to light was assessed to establish its suitability for painting consolidation. The results suggest that citronella oil enhances the effectiveness of glycerol to improve mechanical behaviour and reversibility of the gelatine-based adhesive. Light ageing of the specimens containing the proposed additives produced no remarkable changes in structure, mechanical, water barrier and other functional properties of the adhesives.Financial support is gratefully acknowledged from the Spanish 'I+D+I MICINN' projects CTQ2011-28079-CO3-01 supported by ERDEF funds.Domenech Carbo, MT.; Lee, Y.; Osete Cortina, L.; Martín Rey, S. (2015). Influence of plasticizer and biocide on the functional properties of gelatin-based adhesives used in painting consolidation. Journal of Adhesion Science and Technology. 29(17):1774-1795. https://doi.org/10.1080/01694243.2014.975999S17741795291
Electrochemical analysis of gildings in Valencia altarpieces: a cross-age study since fifteenth until twentieth century, Journal of Solid State Electrochemistry
[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.Financial support from the MINECO Projects CTQ2014-53736-C3-1-P, CTQ2014-53736-C3-2-P and MAT2015-65445-C2-2-R, which are supported with ERDF funds is gratefully acknowledged. Likewise financial support of the Comunidad de Madrid and structural funds of the EU through Programa Geomateriales 2 ref. S2013/MIT-2914 is acknowledged. The authors thank the Seccion de Investigacion Arqueologica Municipal de Valencia for kindly authorizing sampling to carry out this research. The authors also thank Dr. Jose Luis Moya Lopez and Mr. Manuel Planes Insausti (Microscopy Service of the Universitat Politecnica de Valencia) for their technical support.Ferragud Adam, JV.; Piquero-Cilla, J.; Domenech Carbo, MT.; Guerola Blay, V.; Company Climent, J.; Domenech Carbo, A. (2016). Electrochemical analysis of gildings in Valencia altarpieces: a cross-age study since fifteenth until twentieth century, Journal of Solid State Electrochemistry. Journal of Solid State Electrochemistry. 21(5):1477-1487. https://doi.org/10.1007/s10008-017-3512-8S14771487215Le Goff J (1991) El hombre medieval. Alianza Editorial, MadridValero-Cuenca A (2011) El oro: símbolo de lo trascendente en la pintura gótica. Su capacidad como elemento transformador, espiritual y plástico. Archivo de Arte Valenciano XCII. Real Academia de Bellas Artes de San Carlos, ValènciaRodriguez-López A, Khandekar N, Gates G, Newman R (2007) Materials and techniques of a Spanish Renaissance panel painting. Stud Conserv 52:81–100Chao R, Heginbotham A, Lee L, Chiari G (2014) Materials and techniques of gilding on a suite of French eighteenth-century chair. Stud Conserv 59:102–112Alfonso-Muñoz M, Ferragut-Adam X, Guerola-Blay V, Roig-Picazo MP (2008) Intervención en la ornamentación dorada del espacio central y acceso sur de la Basílica de la Virgen de los Desamparados de Valencia. Arché 3:117–126Antonelli F, Lazzarini L, Cancellere S, Tesser E (2016) Study of the deteriortion products, gilding, and polychromy of the stones of the Scuola Grande Di San Marco’s façade in Venice. Stud Conserv 61:74–85Toniolo L, Colombo C, Bruni S, Fermo P, Casoli A, Palla G, Bianchi CL (1998) Gilded stuccoes of the Italian baroque. Stud Conserv 43:201–208De Quinto ML (1984) Los batihojas artesanos del oro. Editora Nacional, MadridLópez-Zamora E (2007) Estudio de los materiales y procedimientos del dorado a través de las fuentes literarias antiguas: aplicación en las decoraciones de pinturas castellanas sobre tabla. PhD Thesis. Universidad Complutense de Madrid, MadridHerranz E (2000) El arte de dorar, 6th edn. Dossat, MadridCrabbe AC, Giumlia-Mair A, Wouters HJM, Terryn H, Vandendael I (2016) De Colorando Auro: Experimenta and literatura study of medieval colouring récipes on gilded plates Stud Conserv 61: 274–285 and references thereinGonzález E (1997) Tratado del dorado, plateado y su policromía (Tecnología, conservación y restauración). Universitat Politècnica de València, ValènciaBaixauli-Juan I (2001) Els artesans de la València del segle XVII: Capítols dels oficis i col·legis. Universitat de València, ValènciaMocholí-Roselló A (2012) Pintors i artífex de la València medieval. Universitat Politècnica de València, ValènciaDoménech-Carbó A, Doménech-Carbó MT, Costa V (2009) In: Scholz F (ed) Electrochemical methods in Archaeometry, conservation and restoration, Monographs in Electrochemistry Series. Springer, Berlin-HeidelbergMelo HP, Cruz AJ, Candelas A, Mirao J, Cardoso AM, Oliveira MJ, Valadas S (2014) Problems of analysis by FTIR of calcium sulphate–based preparatory layers: the case of a group of 16th-century Portuguese paintings. Archaeometry 56:513–526Picollo M, Fukunaga K, Labaune J (2015) Obtaining noninvasive stratigraphic details of panel paintings using terahertz time domain spectroscopy imaging system. J Cult Herit 16:73–80Duran A, Perez-Rodríguez JL, Jimenez de Haro MC, Herrera LK, Justo A (2008) Degradation of gold and false golds used as gildings in the cultural heritage of Andalusia, Spain. J Cult Herit 9:184–188Gulotta D, Goidanich S, Bertoldi M, Bortolotto S, Toniolo L (2012) Gildings and false gildings of the baroque age: characterization and conservation problems. Archaeometry 54:940–954Constantinescu B, Vasilescu A, Radtke M, Reinholz U (2010) Micro-SR-XRF studies for archaeological gold identification—the case of Carpathian gold and Romanian museal objects. Appl Phys A Mater Sci Process 99:383–389Scholz F, Meyer B (1998) In: Bard AJ, Rubinstein I (eds) Voltammetry of solid microparticles immobilized on electrode surfaces, Electroanalytical Chemistry, A Series of Advances, vol 20. Marcel Dekker, New York, pp 1–86Scholz F, Schröder U, Gulaboski R, Doménech-Carbó A (2014) Electrochemistry of immobilized particles and droplets, 2nd edit. Springer, Berlin-HeidelbergDoménech-Carbó A, Labuda J, Scholz F (2013) Electroanalytical chemistry for the analysis of solids: characterization and classification (IUPAC Technical Report). Pure Appl Chem 85:609–631Doménech-Carbó A (2010) Voltammetric methods applied to identification, speciation and quantification of analytes from works of art: an overview. J Solid State Electrochem 14:363–369Doménech-Carbó A (2011) Tracing, authentifying and dating archaeological metal using the voltammetry of microparticles. Anal Methods 3:2181–2188Doménech-Carbó A, Doménech-Carbó MT, Peiró-Ronda MA, Osete-Cortina L (2011) Authentication of archaeological lead artifacts using voltammetry of microparticles: the case of the Tossal de Sant Miquel Iberian plate. Archaeometry 53:1193–1211Doménech-Carbó A, Doménech-Carbó MT, Martínez-Lázaro I (2008) Electrochemical identification of bronze corrosion products in archaeological artefacts. A case study. Microchim Acta 162:351–359Satovic D, Martinez S, Bobrowski A (2010) Electrochemical identification of corrosion products on historical and archaeological bronzes using the voltammetry of micro-particles attached to a carbon paste electrode. Talanta 81:1760–1765Doménech-Carbó A, Doménech-Carbó MT, Martínez-Lázaro I (2010) Layer-by-layer identification of copper alteration products in metallic works of art using the voltammetry of microparticles approach. Anal Chim Acta 610:1–9Cepriá G, Abadías O, Pérez-Arantegui J, Castillo JR (2001) Electrochemical behavior of silver-copper alloys in voltammetry of microparticles: a simple method for screening purposes. Electroanalysis 13:477–483Doménech-Carbó A, Doménech-Carbó MT, Pasíes T, Bouzas MC (2012) Modeling corrosion of archaeological silver-copper coins using the voltammetry of immobilized particles. Electroanalysis 24:1945–1955Capelo S, Homem PM, Cavalheiro J, Fonseca ITE (2013) Linear sweep voltammetry: a cheap and powerful technique for the identification of the silver tarnish layer constituent. J Solid State Electrochem 17:223–234Doménech-Carbó A, Del Hoyo-Rodríguez J, Doménech-Carbó MT, Piquero-Cilla J (2017) Electrochemical analysis of the first Polish coins using the voltammetry of immobilized particles. Microchem J 130:47–55Ferragud X (2015) Estudi de les tècniques del daurat i la policromia sobre l’or a l’escola valenciana del segle XV al segle XIX Analisi dels materials, tècniques i procediments. PhD Thesis, University of ValenciaPlumb RC, Thakkar N (1965) Volta potential studies of the aging of gold surfaces. J Phys Chem 69:439–441Rysiazhnyi V, Slavicek P, Cernak M (2014) Aging of plasma-activated copper and gold surfaces and its hydrophilic recovery after water immersion. This Solid Films 550:373–380Gubicza J, Lábár JL, Quynh LM, Nam NH, Luong NH (2013) Evolution of size and shape of gold nanoparticles during long-time aging. Mater Chem Phys 138:449–453Burke LD, Nugent PF (1997) The electrochemistry of gold: I the redox behaviour of the metal in aqueous media. Gold Bull 30:43–53Chen A, Lipkowski J (1999) Electrochemical and spectroscopic studies of hydroxide adsorption at the Au(111) electrode. J Phys Chem B 103:682–691Hoogvliet JC, van Bennekom WP (2001) Gold thin-film electrodes: an EQCM study of the influence of chromium and titanium adhesion layers on the response. Electrochim Acta 47:599–611Burke LD, O’Mullane AP (2000) Generation of active surface states of gold and the role of such states in electrocatalysis. J Solid State Electrochem 4:285–297Burke LD, O’Mullane AP, Lodge VE, Mooney MB (2001) Auto-inhibition of hydrogen gas evolution on gold in aqueous acid solution. J Solid State Electrochem 5:319–327Doménech-Carbó A, Doménech-Carbó MT, Osete-Cortina L (2004) Electrochemistry of archaeological metals: an approach from the voltammetry of microparticles. In: Brillas E, Cabot P-L (eds) Trends in electrochemistry and corrosion at the beginning of the 21st century (dedicated to Professor Dr. Josep M. Costa on the occasion of his 70th birthday). Universitat de Barcelona, Barcelona, pp 857–871Doyle RL, Lyons MEG (2014) The mechanism of oxygen evolution at superactivated gold electrodes in aqueous alkaline solution. J Solid State Electrochem 18:3271–3286Jeyabharathi C, Hasse U, Ahrens P, Scholz F (2014) Oxygen electroreduction on polycrystalline gold electrodes and on gold nanoparticle-modified glassy carbon electrodes. J Solid State Electrochem 18:3299–3306Jeyabharathi C, Ahrens P, Hasse U, Scholz F (2016) Identification of low-index crystal planes of polycrystalline gold on the basis of electrochemical oxide layer formation. J. Solid State Electrochem 20:3025–3031Cherevko S, Kulyk N, Chung C-H (2012) Utilization of surface active sites on gold in preparation of highly reactive interfaces for alcohols electrooxidation in alkaline media. Electrochim Acta 69:190–196Doménech-Carbó A, Doménech-Carbó MT, Peiró-Ronda MA (2011) ‘One-touch’ voltammetry of microparticles for the identification of corrosion products in archaeological lead. Electroanalysis 23:1391–1400Blum D, Leyffer W, Holze R (1996) Pencil-leads as new electrodes for abrasive stripping voltammetry. Electroanalysis 8:296–297Izumi T, Watanabe I, Yokoyama Y (1991) Activation of a gold electrode by electrochemical oxidation-reduction pretreatment in hydrochloric acid. J Electroanal Chem Interfacial Electrochem 303:151–160Mesgar M, Kaghazchi P, Jacob T, Pichardo-Pedrero E, Giesen M, Ibach H, Luque NB, Schmickler W (2013) Chlorine-enhanced surface mobility of Au(100). ChemPhysChem 14:233–236Scholz F, López de Lara González G, de Carvalho LM, Hilgemann M, Brainina KZ, Kahlert H, Jack RS, Minh DT (2007) Indirect electrochemical sensing of radicals and radical scavengers in biological matrices. Angew Chem Int Ed 46:8079–8081Nowicka A, Hasse U, Sievers G, Donten M, Stojek Z, Fletcher S, Scholz F (2010) Selective knockout of gold active sites. Angew Chem Int Ed 49:3006–3009Hasse U, Fricke K, Dias D, Sievers G, Wulff H, Scholz F (2012) Grain boundary corrosion of the surface of annealed thin layers of gold by OH·radicals. J Solid State Electrochem 16:2383–2389Hasse U, Wulff H, Helm CA, Scholz F (2013) Formation of gold surfaces with a strongly preferred {100}-orientation. J Solid State Electrochem 17:3047–3053Doménech-Carbó A, Doménech-Carbó MT, Pasíes T, Bouzas MC (2011) Application of modified Tafel analysis to the identification of corrosion products on archaeological metals using voltammetry of microparticles. Electroanalysis 23:2803–2812Doménech-Carbó A, Doménech-Carbó MT, Peiró-Ronda MA (2011) Dating archaeological lead artifacts from measurement of the corrosion content using the voltammetry of microparticles. Anal Chem 83:5639–5644Doménech-Carbó A, Doménech-Carbó MT, Peiró-Ronda MA, Martinez-Lázaro I, Barrio J (2012) Application of the voltammetry of microparticles for dating archaeological lead using polarization curves and electrochemical impedance spectroscopy. J Solid State Electrochem 16:2349–2356Doménech-Carbó A, Doménech-Carbó MT, Capelo S, Pasíes T, Martínez-Lázaro I (2014) Dating archaeological copper/bronze artifacts using the voltammetry of microparticles. Angew Chem Int Ed 53:9262–9266Doménech-Carbó A, Capelo S, Piquero J, Doménech-Carbó MT, Barrio J, Fuentes A, Al-Sekkaneh W (2016) Dating archaeological copper using electrochemical impedance spectroscopy. Comparison with voltammetry of microparticles dating. Mater Corr 67:120–12
Evaluación del empleo de biocidas naturales en mezclas adhesivas de base proteica
Los adhesivos naturales empleados en la consolidación de estratos pictóricos, son fácilmente deteriorados por microorganismos y bacterias debido a su composición orgánica. Las soluciones empleadas hasta el momento para su conservación, se fundamentan en la adición de un biocida, que otorgue mayor estabilidad a la mezcla, mejorando así su estabilidad física y química. Estos biocidas, habitualmente son agentes desinfectantes o pesticidas de amplio uso industrial, con graves problemas de toxicidad y peligrosidad para el usuario y su entorno. Progresivamente se han ido mejorando estas formulaciones, adaptándolas a los requerimientos exigidos en intervención del Patrimonio Cultural, pero sin detenerse en el riesgo que su empleo supone para el restaurador. En este estudio, se valoran diferentes bactericidas naturales como alternativa a los materiales más tóxicos empleados actualmente, analizando el poder insecticida o fungistático de cada uno de ellos y su miscibilidad con consolidantes pictóricos de tipo proteico. Concretamente se ha desarrollado el análisis comparativo entre cinco biocidas (Extracto de equinácea, propóleo, esencia de citronella, esencia de ajo y esencia de alcanfor), adicionados a dos tipos de gelatinas animales. Se ha valorado su empleo para los trabajos de consolidación de las policromías sobre madera del Templo Longshan (Lukang, Taiwán), con problemas puntuales de desconsolidación en algunas zonas y en otros casos de cohesión entre sustratos. El objetivo principal se ha fundamentado en la obtención de mezclas adhesivas estables desde el punto de vista de la Conservación y Restauración de los Bienes Culturales, a la vez que atóxicas para el restaurador y el medioambiente.Martín Rey, S.; Lee, Y.; Domenech Carbo, MT. (2011). Evaluación del empleo de biocidas naturales en mezclas adhesivas de base proteica. Arché. (6):273-278. http://hdl.handle.net/10251/34064273278
Maya chemistry of organic inorganic hybrid materials: isomerization, cyclicization and redox tuning of organic dyes attached to porous silicates
[EN] Association of indigo and lapachol dyes to aluminosilicate clays yields polyfunctional organic
– inorganic hybrid materials forming Maya Blue-like systems. Upon partial removing of clay's zeolitic water by moderate thermal treatment, abundant isomerization, cyclicization and oxidation reactions occur defining a‘ Maya chemistry whose complexity could explain the versatile use of such materials in the pre-Columbian cultures and permits the preparation of polyfunctional materials potentially usable for therapeutic and catalytic purposes.Financial support is gratefully acknowledged from the MEC Projects CTQ2011-28079-CO3-01 and 02 which are also supported with ERDF funds.Domenech Carbo, A.; Valle-Algarra, FM.; Domenech Carbo, MT.; Osete Cortina, L.; Domine, ME. (2013). Maya chemistry of organic inorganic hybrid materials: isomerization, cyclicization and redox tuning of organic dyes attached to porous silicates. RSC Advances. 3:20099-20105. https://doi.org/10.1039/c3ra42890gS20099201053Gómez-Romero, P., & Sanchez, C. (2005). Hybrid materials. Functional properties. From Maya Blue to 21st century materials. New J. Chem., 29(1), 57-58. doi:10.1039/b416075bCalzaferri, G., Huber, S., Maas, H., & Minkowski, C. (2003). Host–Guest Antenna Materials. Angewandte Chemie International Edition, 42(32), 3732-3758. doi:10.1002/anie.200300570Doménech, A., Doménech-Carbó, M. T., Sánchez del Río, M., Vázquez de Agredos Pascual, M. L., & Lima, E. (2009). Maya Blue as a nanostructured polyfunctional hybrid organic–inorganic material: the need to change paradigms. New Journal of Chemistry, 33(12), 2371. doi:10.1039/b901942aHubbard, B., Kuang, W., Moser, A., Facey, G. A., & Detellier, C. (2003). Structural study of Maya Blue: textural, thermal and solidstate multinuclear magnetic resonance characterization of the palygorskite-indigo and sepiolite-indigo adducts. Clays and Clay Minerals, 51(3), 318-326. doi:10.1346/ccmn.2003.0510308Fois, E., Gamba, A., & Tilocca, A. (2003). On the unusual stability of Maya blue paint: molecular dynamics simulations. Microporous and Mesoporous Materials, 57(3), 263-272. doi:10.1016/s1387-1811(02)00596-6Sánchez del Río, M., Martinetto, P., Somogyi, A., Reyes-Valerio, C., Dooryhée, E., Peltier, N., … Dran, J.-C. (2004). Microanalysis study of archaeological mural samples containing Maya blue pigment. Spectrochimica Acta Part B: Atomic Spectroscopy, 59(10-11), 1619-1625. doi:10.1016/j.sab.2004.07.027Giustetto, R., Llabrés i Xamena, F. X., Ricchiardi, G., Bordiga, S., Damin, A., Gobetto, R., & Chierotti, M. R. (2005). Maya Blue: A Computational and Spectroscopic Study. The Journal of Physical Chemistry B, 109(41), 19360-19368. doi:10.1021/jp048587hDoménech, A., Doménech-Carbó, M. T., & Vázquez de Agredos Pascual, M. L. (2006). Dehydroindigo: A New Piece into the Maya Blue Puzzle from the Voltammetry of Microparticles Approach. The Journal of Physical Chemistry B, 110(12), 6027-6039. doi:10.1021/jp057301lDoménech, A., Doménech-Carbó, M. T., & Vázquez de Agredos Pascual, M. L. (2007). Indigo/Dehydroindigo/Palygorskite Complex in Maya Blue: An Electrochemical Approach. The Journal of Physical Chemistry C, 111(12), 4585-4595. doi:10.1021/jp067369gDoménech, A., Doménech-Carbó, M. T., & de Agredos Pascual, M. L. V. (2007). Chemometric Study of Maya Blue from the Voltammetry of Microparticles Approach. Analytical Chemistry, 79(7), 2812-2821. doi:10.1021/ac0623686DOMÉNECH, A., DOMÉNECH-CARBÓ, M. T., & VÁZQUEZ DE AGREDOS PASCUAL, M. L. (2009). CORRELATION BETWEEN SPECTRAL, SEM/EDX AND ELECTROCHEMICAL PROPERTIES OF MAYA BLUE: A CHEMOMETRIC STUDY*. Archaeometry, 51(6), 1015-1034. doi:10.1111/j.1475-4754.2009.00453.xDoménech, A., Doménech-Carbó, M. T., & Vázquez de Agredos-Pascual, M. L. (2011). From Maya Blue to «Maya Yellow»: A Connection between Ancient Nanostructured Materials from the Voltammetry of Microparticles. Angewandte Chemie International Edition, 50(25), 5741-5744. doi:10.1002/anie.201100921Doménech, A., Doménech-Carbó, M. T., Vidal-Lorenzo, C., & de Agredos-Pascual, M. L. V. (2011). Insights into the Maya Blue Technology: Greenish Pellets from the Ancient City of La Blanca. Angewandte Chemie International Edition, 51(3), 700-703. doi:10.1002/anie.201106562Doménech, A., Doménech-Carbó, M. T., Sánchez del Río, M., Goberna, S., & Lima, E. (2009). Evidence of Topological Indigo/Dehydroindigo Isomers in Maya Blue-Like Complexes Prepared from Palygorskite and Sepiolite. The Journal of Physical Chemistry C, 113(28), 12118-12131. doi:10.1021/jp900711kDoménech, A., Doménech-Carbó, M. T., del Río, M. S., & de Agredos Pascual, M. L. V. (2008). Comparative study of different indigo-clay Maya Blue-like systems using the voltammetry of microparticles approach. Journal of Solid State Electrochemistry, 13(6), 869-878. doi:10.1007/s10008-008-0616-1Doménech-Carbó, A., Doménech-Carbó, M. T., Valle-Algarra, F. M., Domine, M. E., & Osete-Cortina, L. (2013). On the dehydroindigo contribution to Maya Blue. Journal of Materials Science, 48(20), 7171-7183. doi:10.1007/s10853-013-7534-zDoménech-Carbó, A., Valle-Algarra, F. M., Doménech-Carbó, M. T., Domine, M. E., Osete-Cortina, L., & Gimeno-Adelantado, J. V. (2013). Redox Tuning and Species Distribution in Maya Blue-Type Materials: A Reassessment. ACS Applied Materials & Interfaces, 5(16), 8134-8145. doi:10.1021/am402193uRondão, R., Seixas de Melo, J. S., Bonifácio, V. D. B., & Melo, M. J. (2010). Dehydroindigo, the Forgotten Indigo and Its Contribution to the Color of Maya Blue. The Journal of Physical Chemistry A, 114(4), 1699-1708. doi:10.1021/jp907718kTilocca, A., & Fois, E. (2009). The Color and Stability of Maya Blue: TDDFT Calculations. The Journal of Physical Chemistry C, 113(20), 8683-8687. doi:10.1021/jp810945aGiustetto, R., Seenivasan, K., Bonino, F., Ricchiardi, G., Bordiga, S., Chierotti, M. R., & Gobetto, R. (2011). Host/Guest Interactions in a Sepiolite-Based Maya Blue Pigment: A Spectroscopic Study. The Journal of Physical Chemistry C, 115(34), 16764-16776. doi:10.1021/jp203270cGiustetto, R., & Wahyudi, O. (2011). Sorption of red dyes on palygorskite: Synthesis and stability of red/purple Mayan nanocomposites. Microporous and Mesoporous Materials, 142(1), 221-235. doi:10.1016/j.micromeso.2010.12.004Giustetto, R., Seenivasan, K., Pellerej, D., Ricchiardi, G., & Bordiga, S. (2012). Spectroscopic characterization and photo/thermal resistance of a hybrid palygorskite/methyl red Mayan pigment. Microporous and Mesoporous Materials, 155, 167-176. doi:10.1016/j.micromeso.2012.01.024Sánchez del Río, M., Boccaleri, E., Milanesio, M., Croce, G., van Beek, W., Tsiantos, C., … García-Romero, E. (2009). A combined synchrotron powder diffraction and vibrational study of the thermal treatment of palygorskite–indigo to produce Maya blue. Journal of Materials Science, 44(20), 5524-5536. doi:10.1007/s10853-009-3772-5Mondelli, C., Río, M. S. del, González, M. A., Magazzú, A., Cavallari, C., Suárez, M., … Romano, P. (2012). Role of water on formation and structural features of Maya blue. Journal of Physics: Conference Series, 340, 012109. doi:10.1088/1742-6596/340/1/012109Dejoie, C., Martinetto, P., Dooryhée, E., Strobel, P., Blanc, S., Bordat, P., … Anne, M. (2010). Indigo@Silicalite: a New Organic−Inorganic Hybrid Pigment. ACS Applied Materials & Interfaces, 2(8), 2308-2316. doi:10.1021/am100349bDejoie, C., Martinetto, P., Dooryhée, E., Brown, R., Blanc, S., Bordat, P., … Anne, M. (2011). Diffusion Of Indigo Molecules Inside The Palygorskite Clay Channels. MRS Proceedings, 1319. doi:10.1557/opl.2011.924Ovarlez, S., Giulieri, F., Chaze, A.-M., Delamare, F., Raya, J., & Hirschinger, J. (2009). The Incorporation of Indigo Molecules in Sepiolite Tunnels. Chemistry - A European Journal, 15(42), 11326-11332. doi:10.1002/chem.200901482Ovarlez, S., Giulieri, F., Delamare, F., Sbirrazzuoli, N., & Chaze, A.-M. (2011). Indigo–sepiolite nanohybrids: Temperature-dependent synthesis of two complexes and comparison with indigo–palygorskite systems. Microporous and Mesoporous Materials, 142(1), 371-380. doi:10.1016/j.micromeso.2010.12.025Franç, N. A., Giulieri, oise, Ovarlez, S., & Chaze, A. M. (2012). Indigo/sepiolite nanohybrids: stability of natural pigments inspired by Maya blue. International Journal of Nanotechnology, 9(3/4/5/6/7), 605. doi:10.1504/ijnt.2012.045334Tsiantos, C., Tsampodimou, M., Kacandes, G. H., Sánchez del Río, M., Gionis, V., & Chryssikos, G. D. (2011). Vibrational investigation of indigo–palygorskite association(s) in synthetic Maya blue. Journal of Materials Science, 47(7), 3415-3428. doi:10.1007/s10853-011-6189-xLima, E., Guzmán, A., Vera, M., Rivera, J. L., & Fraissard, J. (2012). Aged Natural and Synthetic Maya Blue-Like Pigments: What Difference Does It Make? The Journal of Physical Chemistry C, 116(7), 4556-4563. doi:10.1021/jp207602mKumagai, Y., Tsurutani, Y., Shinyashiki, M., Homma-Takeda, S., Nakai, Y., Yoshikawa, T., & Shimojo, N. (1997). Bioactivation of lapachol responsible for DNA scission by NADPH-cytochrome P450 reductase. Environmental Toxicology and Pharmacology, 3(4), 245-250. doi:10.1016/s1382-6689(97)00019-7Nasiri, H. R., Bolte, M., & Schwalbe, H. (2008). Electrochemical and crystal structural analysis ofα- and dehydro-α-lapachones. Natural Product Research, 22(14), 1225-1230. doi:10.1080/14786410701654925Garkavtsev, I., Chauhan, V. P., Wong, H. K., Mukhopadhyay, A., Glicksman, M. A., Peterson, R. T., & Jain, R. K. (2011). Dehydro- -lapachone, a plant product with antivascular activity. Proceedings of the National Academy of Sciences, 108(28), 11596-11601. doi:10.1073/pnas.1104225108Doménech-Carbó, A., Labuda, J., & Scholz, F. (2012). Electroanalytical chemistry for the analysis of solids: Characterization and classification (IUPAC Technical Report). Pure and Applied Chemistry, 85(3), 609-631. doi:10.1351/pac-rep-11-11-13Hoffman, R. C., Zilber, R. C., & Hoffman, R. E. (2010). NMR spectroscopic study of the Murex trunculus dyeing process. Magnetic Resonance in Chemistry, 48(11), 892-895. doi:10.1002/mrc.2685Laatsch, H., Thomson, R. H., & Cox, P. J. (1984). Spectroscopic properties of violacein and related compounds: crystal structure of tetramethylviolacein. Journal of the Chemical Society, Perkin Transactions 2, (8), 1331. doi:10.1039/p29840001331Silva, J. F. M. da, Garden, S. J., & Pinto, A. C. (2001). The chemistry of isatins: a review from 1975 to 1999. Journal of the Brazilian Chemical Society, 12(3), 273-324. doi:10.1590/s0103-50532001000300002Doménech-Carbó, A., Martini, M., de Carvalho, L. M., & Doménech-Carbó, M. T. (2012). Square wave voltammetric determination of the redox state of a reversibly oxidized/reduced depolarizer in solution and in solid state. Journal of Electroanalytical Chemistry, 684, 13-19. doi:10.1016/j.jelechem.2012.08.016Doménech, A., Doménech-Carbó, M. T., Osete-Cortina, L., & Montoya, N. (2013). Application of solid-state electrochemistry techniques to polyfunctional organic–inorganic hybrid materials: The Maya Blue problem. Microporous and Mesoporous Materials, 166, 123-130. doi:10.1016/j.micromeso.2012.04.031Bond, A. M., Marken, F., Hill, E., Compton, R. G., & Hügel, H. (1997). The electrochemical reduction of indigo dissolved in organic solvents and as a solid mechanically attached to a basal plane pyrolytic graphite electrode immersed in aqueous electrolyte solution. Journal of the Chemical Society, Perkin Transactions 2, (9), 1735-1742. doi:10.1039/a701003fHe, H., Ding, Z., & Shoesmith, D. W. (2009). The determination of electrochemical reactivity and sustainability on individual hyper-stoichiometric UO2+x grains by Raman microspectroscopy and scanning electrochemical microscopy. Electrochemistry Communications, 11(8), 1724-1727. doi:10.1016/j.elecom.2009.07.013Guadagnini, L., Maljusch, A., Chen, X., Neugebauer, S., Tonelli, D., & Schuhmann, W. (2009). Visualization of electrocatalytic activity of microstructured metal hexacyanoferrates by means of redox competition mode of scanning electrochemical microscopy (RC-SECM). Electrochimica Acta, 54(14), 3753-3758. doi:10.1016/j.electacta.2009.01.076Yasarawan, N., & van Duijneveldt, J. S. (2008). Dichroism in Dye-Doped Colloidal Liquid Crystals. Langmuir, 24(14), 7184-7192. doi:10.1021/la800849yPires, S. M. G., Paula, R. D., Simões, M. M. Q., Silva, A. M. S., Domingues, M. R. M., Santos, I. C. M. S., … Cavaleiro, J. A. S. (2011). Novel biomimetic oxidation of lapachol with H2O2 catalysed by a manganese(iii) porphyrin complex. RSC Advances, 1(7), 1195. doi:10.1039/c1ra00578bNiehues, M., Barros, V. P., Emery, F. da S., Dias-Baruffi, M., Assis, M. das D., & Lopes, N. P. (2012). Biomimetic in vitro oxidation of lapachol: A model to predict and analyse the in vivo phase I metabolism of bioactive compounds. European Journal of Medicinal Chemistry, 54, 804-812. doi:10.1016/j.ejmech.2012.06.042Ferraz, P. A. ., de Abreu, F. C., Pinto, A. V., Glezer, V., Tonholo, J., & Goulart, M. O. . (2001). Electrochemical aspects of the reduction of biologically active 2-hydroxy-3-alkyl-1,4-naphthoquinones. Journal of Electroanalytical Chemistry, 507(1-2), 275-286. doi:10.1016/s0022-0728(01)00439-9Abreu, F. C., Goulart, M. O. F., & Brett, A. M. O. (2002). Reduction of Lapachones in Aqueous Media at a Glassy Carbon Electrode. Electroanalysis, 14(1), 29-34. doi:10.1002/1521-4109(200201)14:13.0.co;2-aNgameni, E., Tonle, I. K., Nanseu, C. P., & Wandji, R. (2000). Voltammetry Study of 2-Hydroxy-3-isopropenyl-1,4-naphthoquinone Using a Carbon Paste Electrode. Electroanalysis, 12(11), 847-852. doi:10.1002/1521-4109(200007)12:113.0.co;2-9Goulart, M. O. F., Lima, N. M. F., Sant’Ana, A. E. G., Ferraz, P. A. L., Cavalcanti, J. C. M., Falkowski, P., … Liwo, A. (2004). Electrochemical studies of isolapachol with emphasis on oxygen interaction with its radical anions. Journal of Electroanalytical Chemistry, 566(1), 25-29. doi:10.1016/j.jelechem.2003.10.043Jungbluth, G., Rühling, I., & Ternes, W. (2000). Oxidation of flavonols with Cu(II), Fe(II) and Fe(III) in aqueous media. Journal of the Chemical Society, Perkin Transactions 2, (9), 1946-1952. doi:10.1039/b002323jCaamal-Fuentes, E., Torres-Tapia, L. W., Simá-Polanco, P., Peraza-Sánchez, S. R., & Moo-Puc, R. (2011). Screening of plants used in Mayan traditional medicine to treat cancer-like symptoms. Journal of Ethnopharmacology, 135(3), 719-724. doi:10.1016/j.jep.2011.04.004Arnold, D. E., Bohor, B. F., Neff, H., Feinman, G. M., Williams, P. R., Dussubieux, L., & Bishop, R. (2012). The first direct evidence of pre-columbian sources of palygorskite for Maya Blue. Journal of Archaeological Science, 39(7), 2252-2260. doi:10.1016/j.jas.2012.02.03
- …