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Tin was a very important alloying element in Western Europe in the production of bronze (Cu-Sn alloy) since the second millennium BC (Bronze Age), when most metallic artefacts were made of this alloy. Smelting experiments using cassiterite collected in the NW Iberian territory were made to produce tin in a very simple and small scale manner, using a small open pit structure to reproduce what could have been the manufacturing process of tin in prehistoric times. Chemical and structural analysis of the products by XRF, SEM-EDS and XRD were made to achieve a detailed knowledge of the characteristics of the materials. Additionally, an X-ray absorption near-edge structure region (XANES) study was performed on three types of slags previously identified (Type 1, Type 2 and Type 3) to obtain information on the oxidation state of Sn. The analyses were made at the European Synchrotron Radiation Facility (ESRF) at the beamline SpLine BM 25A (5-45 keV). N/A

The Fronteira Palace located in Lisbon was built during the second half of the seventeenth century. The Palace is known for its unique azulejos (Portuguese glazed tiles) dated from the 17th and 18th century which were profusely used both in the interior of the palace and on its magnificent formal gardens. The gardens have a unique cladding of high relief lustre tiles combined with blue-and-white tiles adorning the Gallery of the Kings (Figure 1). Samples of azulejos from Gallery of the Kings, were characterized in a previous work by PIXE. They display a silica alkali-lead glass or silica alkali glass and chromophores based on Co for the blue colouring and Cu for the red-lustre effect . In fact, the analyses showed that the colourless glaze has a lead-alkali silicate composition and a copper-rich lustre overlay, in agreement with the Manise lustreware production (Spain) after the XVII century. To achieve a comparison between manufacturing techniques and pigments used samples were characterized using X-Ray Absorption Spectroscopy. XANES techniques can provide information on the structural behaviour of transition metals in the vitreous matrix - namely, their bonding state and coordination environment, providing relevant information regarding the Co and Cu as chromophores. N/A

The last eruption of the Fogo volcano, in the Cape Verde Archipelago, occurred in 2014-2015. A mineralogical and chemical study was undertaken on fumarole incrustations resulting from this event and compared with results obtained from the previous 1995 eruption. The mineralogical constitution of the fumarole deposits was assessed by X-ray diffraction and the chemical characterization was performed through X-ray fluorescence spectrometry with a wavelength dispersive system and by energy dispersive X-ray fluorescence at the European Synchrotron Radiation Facility. The most common compounds/minerals in solid deposits were sulfur, sodium chloride, and calcium sulphates with variable degrees of hydration, sodium sulphate, hydrated sulphates of sodium aluminum, potassium magnesium, or sodium magnesium and a fluorine-bearing mineral. Thenardite (Na2SO4) and its polymorph (phase III) were found simultaneously for the first time in incrustations, to the best of our knowledge. A large span of minor and trace elements present in incrustations (Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Y, Zr, Nb, Mo, Ba, Ce, Tl, Pb) were also identified, some of them potentially hazardous to animal and human health. This study reveals that low temperature incrustations, allied to the atmospheric conditions of Fogo volcano, constitute a natural laboratory to observe the process of mineral formation-namely the Na2SO4 phase III considered metastable. This research received financial support from FCT (Fundação para a Ciência e Tecnologia) through project FIRE (PTDC/GEO-GEO/1123/2014). We acknowledge the European Synchrotron Radiation Facility for provision of synchrotron radiation facilities and in particular in using beamline BM 25A. Special thanks are due to the guides Manuel Montrond Fernandes (Izaquiel) and Edimar Montrond that helped us in the Fogo volcano. J.P. Veiga acknowledges funding by FEDER funds through the COMPETE 2020 Programme and National Funds through FCT-Portuguese Foundation for Science and Technology under the project UID/CTM/50025/2013 and the funding from the European Union Horizon 2020 research and innovation programme H2020-DRS-2015 GA nr. 700395 (HERACLES project). Carla Candeias would also like to acknowledge FCT by the grant SFRH/BPD/99636/2014 and UID/GEO/04035/2013. Special thanks are also due to Dr. Tonci Balic-Žunic, an anonymous reviewer and to the editors for their comments on the manuscript. We are also grateful to Dr. Lídia Quental for the satellite image of Fogo Island.

info:eu-repo/semantics/publishedVersion

Final publication at http://doi.org/10.1016/j.jallcom.2017.12.342, © 2017 Elsevier B.V., The present work seeks to analyse the structural and magnetic properties of cobalt ferrite nanoparticles obtained by electrochemical synthesis by high-resolution transmission electronic microscopy (HRTEM), X-ray absorption spectroscopy (XAS), Mössbauer spectroscopy (MS), neutron diffraction (ND) and SQUID magnetometer. The cationic distribution is analyzed by different techniques. The inversion degree determined by the most accurate measurements was 0.73(1), and the formula for the nanoparticles therefore was (↑Co 0.27 Fe 0.73 )[↓Co 0.73 Fe 1.27 ]O 4 . The magnetic moment found from DC and Mössbauer spectroscopy measurements was 3.8(3) μB, and the coercivity was 7870 Oe at 100 K., This work is supported by the MINECO/FEDER Project MAT2015-67557-C2-2-P

Tesis doctoral inédita. Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Física Aplicada. Fecha de lectura: 16-12-2011

[EN] The purpose of this work is to fabricate self-assembled microstructures by the sol–gel method and study the morphological, structural and compositional dependence of 3-Fe2O3 nanoparticles embedded in silica when glycerol (GLY) and cetyl-trimethylammonium bromide (CTAB) are added as steric agents simultaneously. The combined action of a polyalcohol and a surfactant significantly modifies the morphology of the sample giving rise to a different microstructure in each of the studied cases (1, 3 and 7 days of magnetic stirring time). This is due to the fact that the addition of these two compounds leads to a considerable increase in gelation time as GLY can interact with the alkoxide group on the surface of the iron oxide precursor micelle and/or be incorporated into the hydrophilic chains of CTAB. This last effect causes the iron oxide precursor micelles to be interconnected forming aggregates whose size and structure depend on the magnetic stirring time of the sol–gel synthetic route. In this paper, crystalline structure, composition, purity and morphology of the sol–gel coatings densified at 960 ºC are examined. Emphasis is placed on the nominal percentage of the different iron oxides found in the samples and on the morphological and structural differences. This work implies the possibility of patterning 3-Fe2O3 nanoparticles in coatings and controlling their purity by an easy one-pot sol–gel method., Spanish Ministry of Industry, Economy and Competitiveness for financing the project MAT2015-65445-C2-1-R, MAT2017-86450-C4-1-R, MAT2015-67557-C2-1-P, by the Comunidad de Madrid S2013/MIT-2850 NANOFRONTMAG and H2020 AMPHIBIAN Project ID: 720853. The authors are also grateful to the BM25-SpLine staff for their valuable technical support beyond their duties and for the financial support from the Spanish Ministry of Science, Innovation and Universities (MICIU) and The Spanish National Research Council (CSIC) under Grant No. PIE 2010- 6OE-013, The ESRF – The European Synchrotron, MICIU and CSIC are acknowledged for provision of synchrotron radiation facilities. A. S. acknowledges the Financial support from the Comunidad de Madrid for an “Atracción de Talento Investigador” contract (No. 2017-t2/IND5395).