The Experts below are selected from a list of 303 Experts worldwide ranked by ideXlab platform
Trinitat Pradell - One of the best experts on this subject based on the ideXlab platform.
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Microanalytical study of Luster glazed gilding and silvering from Baroque altarpieces
Pure and Applied Chemistry, 2017Co-Authors: Nati Salvadó, Salvador Butí, Carme Clemente, Victòria Beltran, Gianfelice Cinque, Jordi Juanhuix, Trinitat PradellAbstract:Abstract Lustering, a technique which involved the application of coloured translucent glazes over gilding and silvering was widely used to enrich and decorate altarpieces in the Baroque period. The decorations consist of a micrometric multilayered structure including several color glazes, metallic leaves and bole applied over a plaster ground. The collection of Baroque altarpieces, the oldest dating 1671 and the newest 1775 from the cathedral of Tortosa (Catalonia), is a perfect case of study of the materials used and the techniques employed throughout the period. Further information is obtained from the analysis of the reaction and aging compounds resulting from the interaction among the compounds present in the layers and between the different layers. A combination of sensitive analytical techniques, Synchrotron based μ-XRD and μ-IR and SEM-EDS which enabled the Luster samples to undergo analysis without altering their original layered microstructure were selected. The nature of the compounds used to produce the yellow, green, red and blue glazes (pigments, pigment lakes and resins), metallic leaves and boles is presented. Relevant information from historical and conservation viewpoints about the origin and nature of the materials used, the making of the Lusters and their reactivity and aging are also discussed.
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Temperature resolved reproduction of medieval Luster
Applied Physics A, 2007Co-Authors: Trinitat Pradell, Judit Molera, Emmanuel Pantos, Andrew D. Smith, C.m. Martin, A. LabradorAbstract:Luster is a golden metallic-like decoration produced on glazed ceramics since early Islamic times (Iraq, 9th AD). Luster is obtained by the reaction of a Luster paint and the glaze surface over which it is applied. A temperature-resolved XRD experiment was designed to study the high temperature reactions in the Luster paint while the Luster layer is formed. The Luster paint composition has been made based on the original Luster paints found during the excavation of the 13th AD workshop site at Paterna (Valencia).
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Metallic and nonmetallic shine in Luster: An elastic ion backscattering study
Journal of Applied Physics, 2007Co-Authors: Trinitat Pradell, Judit Molera, Pere Roura, Aurelio Climent-font, Alessandro Zucchiatti, M.d. Ynsa, Daniel CrespoAbstract:Luster is a metal glass nanocomposite layer first produced in the Middle East in early Islamic times (9th AD) made of metal copper or silver nanoparticles embedded in a silica-based glassy matrix. These nanoparticles are produced by ion exchange between Cu+ and Ag+ and alkaline ions from the glassy matrix and further growth in a reducing atmosphere. The most striking property of Luster is its capability of reflecting light like a continuous metal layer and it was unexpectedly found to be linked to one single production parameter: the presence of lead in the glassy matrix composition. The purpose of this article is to describe the characteristics and differences of the nanoparticle layers developed on lead rich and lead free glasses. Copper Luster layers obtained using the ancient recipes and methods are analyzed by means of elastic ion backscattering spectroscopy associated with other analytical techniques. The depth profile of the different elements is determined, showing that the Luster layer formed in ...
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Key Parameters in the Production of Medieval Luster Colors and Shines
Journal of the American Ceramic Society, 2007Co-Authors: Judit Molera, Pere Roura, Cristina Bayés, Daniel Crespo, Trinitat PradellAbstract:Lusters of different color and reflectivity were obtained under controlled conditions in a laboratory using medieval recipes. In this study, we analyze the influence of paint recipes, glaze compositions, and thermal paths and atmospheres on the final aspect and characteristics of the Ag/Cu nanocomposite layer formed. The colors and reflectivity of the medieval Lusters were successfully reproduced using the cinnabar-containing recipes as basic Luster paints. X-ray diffraction, Optical UV-Vis spectra, and microprobe chemical analysis were carried out to determine the composition and the nature and size of the nanoparticles and their relationship with their optical properties.
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Luster decoration of ceramics: mechanisms of metallic Luster formation
Applied Physics A, 2006Co-Authors: Trinitat Pradell, Judit Molera, C. Bayés, Pere RouraAbstract:Luster is a metallic decoration produced since early Islamic times (9th century AD in Iraq). Different studies have shown that medieval Lusters are a metal-glass nanocomposite (metal nanoparticles embodied in a silica glassy matrix) obtained from the reaction of a copper and/or silver containing paint with a glaze. The mechanisms of formation of these metallic-like layers are investigated by laboratory reproductions of Medieval Luster. Copper and silver Lusters are obtained based on different thermal paths and atmospheres, and by using different glaze compositions. The ionic exchange between Cu+ and Ag+ ions from the Luster paint with Na+ and K+ of the glaze, is demonstrated in either oxidizing or inert atmospheres and at firing temperatures between 500 °C and 600 °C. The reduction of copper and silver to their metallic state is obtained by introducing a reducing gas afterwards. The Lusters are non-metallic red ruby copper or green with brown spots silver when developed over alkaline glazes, while they appear coppery and golden metallic when developed over mixed alkaline-lead glazes. SR-XRD, optical absorption and microprobe chemical analysis of the Lusters indicate that the total amount of copper and silver, and the nature and size of the nanoparticles, are similar in both cases. Further work is needed to clarify the origin of these differences.
Judit Molera - One of the best experts on this subject based on the ideXlab platform.
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Temperature resolved reproduction of medieval Luster
Applied Physics A, 2007Co-Authors: Trinitat Pradell, Judit Molera, Emmanuel Pantos, Andrew D. Smith, C.m. Martin, A. LabradorAbstract:Luster is a golden metallic-like decoration produced on glazed ceramics since early Islamic times (Iraq, 9th AD). Luster is obtained by the reaction of a Luster paint and the glaze surface over which it is applied. A temperature-resolved XRD experiment was designed to study the high temperature reactions in the Luster paint while the Luster layer is formed. The Luster paint composition has been made based on the original Luster paints found during the excavation of the 13th AD workshop site at Paterna (Valencia).
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Metallic and nonmetallic shine in Luster: An elastic ion backscattering study
Journal of Applied Physics, 2007Co-Authors: Trinitat Pradell, Judit Molera, Pere Roura, Aurelio Climent-font, Alessandro Zucchiatti, M.d. Ynsa, Daniel CrespoAbstract:Luster is a metal glass nanocomposite layer first produced in the Middle East in early Islamic times (9th AD) made of metal copper or silver nanoparticles embedded in a silica-based glassy matrix. These nanoparticles are produced by ion exchange between Cu+ and Ag+ and alkaline ions from the glassy matrix and further growth in a reducing atmosphere. The most striking property of Luster is its capability of reflecting light like a continuous metal layer and it was unexpectedly found to be linked to one single production parameter: the presence of lead in the glassy matrix composition. The purpose of this article is to describe the characteristics and differences of the nanoparticle layers developed on lead rich and lead free glasses. Copper Luster layers obtained using the ancient recipes and methods are analyzed by means of elastic ion backscattering spectroscopy associated with other analytical techniques. The depth profile of the different elements is determined, showing that the Luster layer formed in ...
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Key Parameters in the Production of Medieval Luster Colors and Shines
Journal of the American Ceramic Society, 2007Co-Authors: Judit Molera, Pere Roura, Cristina Bayés, Daniel Crespo, Trinitat PradellAbstract:Lusters of different color and reflectivity were obtained under controlled conditions in a laboratory using medieval recipes. In this study, we analyze the influence of paint recipes, glaze compositions, and thermal paths and atmospheres on the final aspect and characteristics of the Ag/Cu nanocomposite layer formed. The colors and reflectivity of the medieval Lusters were successfully reproduced using the cinnabar-containing recipes as basic Luster paints. X-ray diffraction, Optical UV-Vis spectra, and microprobe chemical analysis were carried out to determine the composition and the nature and size of the nanoparticles and their relationship with their optical properties.
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Luster decoration of ceramics: mechanisms of metallic Luster formation
Applied Physics A, 2006Co-Authors: Trinitat Pradell, Judit Molera, C. Bayés, Pere RouraAbstract:Luster is a metallic decoration produced since early Islamic times (9th century AD in Iraq). Different studies have shown that medieval Lusters are a metal-glass nanocomposite (metal nanoparticles embodied in a silica glassy matrix) obtained from the reaction of a copper and/or silver containing paint with a glaze. The mechanisms of formation of these metallic-like layers are investigated by laboratory reproductions of Medieval Luster. Copper and silver Lusters are obtained based on different thermal paths and atmospheres, and by using different glaze compositions. The ionic exchange between Cu+ and Ag+ ions from the Luster paint with Na+ and K+ of the glaze, is demonstrated in either oxidizing or inert atmospheres and at firing temperatures between 500 °C and 600 °C. The reduction of copper and silver to their metallic state is obtained by introducing a reducing gas afterwards. The Lusters are non-metallic red ruby copper or green with brown spots silver when developed over alkaline glazes, while they appear coppery and golden metallic when developed over mixed alkaline-lead glazes. SR-XRD, optical absorption and microprobe chemical analysis of the Lusters indicate that the total amount of copper and silver, and the nature and size of the nanoparticles, are similar in both cases. Further work is needed to clarify the origin of these differences.
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ionic exchange mechanism in the formation of medieval Luster decorations
Journal of the American Ceramic Society, 2005Co-Authors: Trinitat Pradell, Judit Molera, Emmanuel Pantos, Josep Roqué, M Vendrellsaz, A D Smith, Daniel CrespoAbstract:Analysis of medieval Luster ceramics seems to indicate that the formation of Luster layers could involve an ion exchange between some alkali ions of the glaze (Na+ and K+), and copper and silver cations of the Luster raw paint during firing. However, because of the weathering shown by the medieval Luster decorations analyzed, conclusive proof is difficult to obtain. A realistic reproduction of the Luster decorations has been fabricated in order to follow the process of formation of the Luster layer. This has been studied by optical microscopy, transmission electron microscopy, electron probe microanalysis, extended X-ray absorption fine structure, X-ray absorption near-edge structure, and the results give direct evidence that ion exchange and diffusion are the physical–chemical mechanisms responsible for the introduction of copper and silver into the glaze.
D. Young - One of the best experts on this subject based on the ideXlab platform.
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Luster wireless sensor network for environmental research
International Conference on Embedded Networked Sensor Systems, 2007Co-Authors: Leo Selavo, Anthony D Wood, Qiuhua Cao, Hengchang Liu, Woochul Kang, Yafeng Wu, John A. Stankovic, Tamim Sookoor, A. Srinivasan, D. YoungAbstract:Environmental wireless sensor network (EWSN) systems are deployed in potentially harsh and remote environments where inevitable node and communication failures must be tolerated. Luster---Light Under Shrub Thicket for Environmental Research---is a system that meets the challenges of EWSNs using a hierarchical architecture that includes distributed reliable storage, delay-tolerant networking, and deployment time validation techniques. In Luster, a fleet of sensors coordinate communications using LiteTDMA, a low-power cLuster-based MAC protocol. They measure the complex light environment in thickets and are open to additional ecological parameters, such as temperature and CO2. Luster has been deployed and evaluated in laboratory, forested, and barrier island environments. It includes new sensor hardware designs: (a) "SolarDust," a hybrid multichannel energy harvesting and sensing device; (b) "Medusa," a spatially reconfigurable light sensor; (c) a removable SD card storage node; and, (d) in-situ user interface tool for deployment time validation.
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SenSys - Luster: wireless sensor network for environmental research
Proceedings of the 5th international conference on Embedded networked sensor systems - SenSys '07, 2007Co-Authors: Leo Selavo, Anthony D Wood, Qiuhua Cao, Hengchang Liu, Woochul Kang, John A. Stankovic, Tamim Sookoor, A. Srinivasan, D. YoungAbstract:Environmental wireless sensor network (EWSN) systems are deployed in potentially harsh and remote environments where inevitable node and communication failures must be tolerated. Luster---Light Under Shrub Thicket for Environmental Research---is a system that meets the challenges of EWSNs using a hierarchical architecture that includes distributed reliable storage, delay-tolerant networking, and deployment time validation techniques. In Luster, a fleet of sensors coordinate communications using LiteTDMA, a low-power cLuster-based MAC protocol. They measure the complex light environment in thickets and are open to additional ecological parameters, such as temperature and CO2. Luster has been deployed and evaluated in laboratory, forested, and barrier island environments. It includes new sensor hardware designs: (a) "SolarDust," a hybrid multichannel energy harvesting and sensing device; (b) "Medusa," a spatially reconfigurable light sensor; (c) a removable SD card storage node; and, (d) in-situ user interface tool for deployment time validation.
Leo Selavo - One of the best experts on this subject based on the ideXlab platform.
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Luster wireless sensor network for environmental research
International Conference on Embedded Networked Sensor Systems, 2007Co-Authors: Leo Selavo, Anthony D Wood, Qiuhua Cao, Hengchang Liu, Woochul Kang, Yafeng Wu, John A. Stankovic, Tamim Sookoor, A. Srinivasan, D. YoungAbstract:Environmental wireless sensor network (EWSN) systems are deployed in potentially harsh and remote environments where inevitable node and communication failures must be tolerated. Luster---Light Under Shrub Thicket for Environmental Research---is a system that meets the challenges of EWSNs using a hierarchical architecture that includes distributed reliable storage, delay-tolerant networking, and deployment time validation techniques. In Luster, a fleet of sensors coordinate communications using LiteTDMA, a low-power cLuster-based MAC protocol. They measure the complex light environment in thickets and are open to additional ecological parameters, such as temperature and CO2. Luster has been deployed and evaluated in laboratory, forested, and barrier island environments. It includes new sensor hardware designs: (a) "SolarDust," a hybrid multichannel energy harvesting and sensing device; (b) "Medusa," a spatially reconfigurable light sensor; (c) a removable SD card storage node; and, (d) in-situ user interface tool for deployment time validation.
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SenSys - Luster: wireless sensor network for environmental research
Proceedings of the 5th international conference on Embedded networked sensor systems - SenSys '07, 2007Co-Authors: Leo Selavo, Anthony D Wood, Qiuhua Cao, Hengchang Liu, Woochul Kang, John A. Stankovic, Tamim Sookoor, A. Srinivasan, D. YoungAbstract:Environmental wireless sensor network (EWSN) systems are deployed in potentially harsh and remote environments where inevitable node and communication failures must be tolerated. Luster---Light Under Shrub Thicket for Environmental Research---is a system that meets the challenges of EWSNs using a hierarchical architecture that includes distributed reliable storage, delay-tolerant networking, and deployment time validation techniques. In Luster, a fleet of sensors coordinate communications using LiteTDMA, a low-power cLuster-based MAC protocol. They measure the complex light environment in thickets and are open to additional ecological parameters, such as temperature and CO2. Luster has been deployed and evaluated in laboratory, forested, and barrier island environments. It includes new sensor hardware designs: (a) "SolarDust," a hybrid multichannel energy harvesting and sensing device; (b) "Medusa," a spatially reconfigurable light sensor; (c) a removable SD card storage node; and, (d) in-situ user interface tool for deployment time validation.
Emmanuel Pantos - One of the best experts on this subject based on the ideXlab platform.
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Temperature resolved reproduction of medieval Luster
Applied Physics A, 2007Co-Authors: Trinitat Pradell, Judit Molera, Emmanuel Pantos, Andrew D. Smith, C.m. Martin, A. LabradorAbstract:Luster is a golden metallic-like decoration produced on glazed ceramics since early Islamic times (Iraq, 9th AD). Luster is obtained by the reaction of a Luster paint and the glaze surface over which it is applied. A temperature-resolved XRD experiment was designed to study the high temperature reactions in the Luster paint while the Luster layer is formed. The Luster paint composition has been made based on the original Luster paints found during the excavation of the 13th AD workshop site at Paterna (Valencia).
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ionic exchange mechanism in the formation of medieval Luster decorations
Journal of the American Ceramic Society, 2005Co-Authors: Trinitat Pradell, Judit Molera, Emmanuel Pantos, Josep Roqué, M Vendrellsaz, A D Smith, Daniel CrespoAbstract:Analysis of medieval Luster ceramics seems to indicate that the formation of Luster layers could involve an ion exchange between some alkali ions of the glaze (Na+ and K+), and copper and silver cations of the Luster raw paint during firing. However, because of the weathering shown by the medieval Luster decorations analyzed, conclusive proof is difficult to obtain. A realistic reproduction of the Luster decorations has been fabricated in order to follow the process of formation of the Luster layer. This has been studied by optical microscopy, transmission electron microscopy, electron probe microanalysis, extended X-ray absorption fine structure, X-ray absorption near-edge structure, and the results give direct evidence that ion exchange and diffusion are the physical–chemical mechanisms responsible for the introduction of copper and silver into the glaze.
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Ionic‐Exchange Mechanism in the Formation of Medieval Luster Decorations
Journal of the American Ceramic Society, 2005Co-Authors: Trinitat Pradell, Judit Molera, Emmanuel Pantos, Andrew D. Smith, Josep Roqué, M. Vendrell-saz, Daniel CrespoAbstract:Analysis of medieval Luster ceramics seems to indicate that the formation of Luster layers could involve an ion exchange between some alkali ions of the glaze (Na+ and K+), and copper and silver cations of the Luster raw paint during firing. However, because of the weathering shown by the medieval Luster decorations analyzed, conclusive proof is difficult to obtain. A realistic reproduction of the Luster decorations has been fabricated in order to follow the process of formation of the Luster layer. This has been studied by optical microscopy, transmission electron microscopy, electron probe microanalysis, extended X-ray absorption fine structure, X-ray absorption near-edge structure, and the results give direct evidence that ion exchange and diffusion are the physical–chemical mechanisms responsible for the introduction of copper and silver into the glaze.
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role of cinnabar in Luster production
Journal of the American Ceramic Society, 2004Co-Authors: Trinitat Pradell, Judit Molera, M. Vendrell, Emmanuel Pantos, Mark A. Roberts, Josefina Perezarantegui, Marco DimichielAbstract:Ancient documentation referring to the use of cinnabar in the production of Luster decorations has recently been corroborated by archaeological findings. However, Luster decorations do not show any trace of the use of cinnabar in their composition because the temperatures involved in Luster firing (500°–600°C) result in the complete decomposition and volatilization of cinnabar. An in situ x-ray diffraction experiment was designed to clarify the role of cinnabar in the production of Luster decorations. The high-energy, high-flux radiation ID15B beamline at the European Synchrotron Radiation Facility was necessary to ensure good time/temperature resolution, penetration, and high-quality data. Results show that cinnabar acts as a reducing agent for copper because it provides the formation of copper (Cu+) and silver (Ag+) sulfur-containing phases, and it inhibits the crystallization of metallic silver in the temperature range of interest in Luster production. The addition of elemental sulfur also produces these phases, but at temperatures <500°C, which are not adequate for the production of copper-containing Lusters.
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Role of Cinnabar in Luster Production
Journal of the American Ceramic Society, 2004Co-Authors: Trinitat Pradell, Judit Molera, M. Vendrell, Josefina Pérez-arantegui, Emmanuel Pantos, Mark A. Roberts, Marco DimichielAbstract:Ancient documentation referring to the use of cinnabar in the production of Luster decorations has recently been corroborated by archaeological findings. However, Luster decorations do not show any trace of the use of cinnabar in their composition because the temperatures involved in Luster firing (500°–600°C) result in the complete decomposition and volatilization of cinnabar. An in situ x-ray diffraction experiment was designed to clarify the role of cinnabar in the production of Luster decorations. The high-energy, high-flux radiation ID15B beamline at the European Synchrotron Radiation Facility was necessary to ensure good time/temperature resolution, penetration, and high-quality data. Results show that cinnabar acts as a reducing agent for copper because it provides the formation of copper (Cu+) and silver (Ag+) sulfur-containing phases, and it inhibits the crystallization of metallic silver in the temperature range of interest in Luster production. The addition of elemental sulfur also produces these phases, but at temperatures
