Publications

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2019
Silva, TP, D. P. S. Oliveira, JP Veiga, P. Ávila, C. Candeias, E. Salas-Colera, and R. Caldeira. "Mineralogy and chemistry of incrustations resulting from the 2014–2015 eruption of Fogo volcano, Cape Verde." Bulletin of Volcanology. 81.4 (2019): 23 (17 pp).
2018
Figueiredo, E., J. Fonte, A. Lima, JP Veiga, R. J. C. Silva, and J. Mirão. "Ancient tin production: Slags from the Iron Age Carvalhelhos hillfort (NW Iberian Peninsula)." Journal of Archaeological Science. 93 (2018): 1-16.
Carvalho, F., A. Lopes, A. T. Curulli, TP Silva, M. M. A. Lima, G. Montesperelli, S. Ronca, G. Padeletti, and JP Veiga. "The Case Study of the Medieval Town Walls of Gubbio in Italy: First Results on the Characterization of Mortars and Binders." Heritage. 1.2 (2018): 468-478.
Monteiro, R. C. C., A. A. S. Lopes, M. M. R. A. Lima, and J. P. B. Veiga. "Thermal characteristics and crystallization behavior of zinc borosilicate glasses containing Nb2O5." Journal of Non-Crystalline Solids. 491 (2018): 124-132.
2017
Kullberg, A. T. G., A. A. S. Lopes, J. P. B. Veiga, and R. C. C. Monteiro. "Crystal growth in zinc borosilicate glasses." Journal of Crystal Growth. 457 (2017): 239-243. AbstractWebsite

Glass samples with a molar composition (64+x)ZnO-(16-x)B2O3-20SiO2, where x=0 or 1, were successfully synthesized using a melt-quenching technique. Based on differential thermal analysis data, the produced glass samples were submitted to controlled heat-treatments at selected temperatures (610, 615 and 620{\{}$\backslash$textdegree{\}}C) during various times ranging from 8 to 30h. The crystallization of willemite (Zn2SiO4) within the glass matrix was confirmed by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). Under specific heat-treatment conditions, transparent nanocomposite glass-ceramics were obtained, as confirmed by UV-vis spectroscopy. The influence of temperature, holding time and glass composition on crystal growth was investigated. The mean crystallite size was determined by image analysis on SEM micrographs. The results indicated an increase on the crystallite size and density with time and temperature. The change of crystallite size with time for the heat-treatments at 615 and 620{\{}$\backslash$textdegree{\}}C depended on the glass composition. Under fixed heat-treatment conditions, the crystallite density was comparatively higher for the glass composition with higher ZnO content. {\{}©{\}} 2016.

Figueiredo, E., A. Lackinger, B. C. Rey, R. J. C. Silva, JP Veiga, and J. Mirão. "An Experimental Approach for Smelting Tin Ores From Northwestern Iberia." Materials and Manufacturing Processes. 32 (2017): 765-774.
Silva, TP, D. P. S. Oliveira, M. J. Batista, JP Veiga, F. Noronha, and J. X. Matos. "Rhenium ocurrence in Portugal: an overview considering the valorisation of mineral resources." Rhenium, Properties, Uses and Occurrences. Ed. Eric James. New York: Nova Science Publishers Inc. New York, 2017. 85-116.
2016
Coutinho, M. L., JP Veiga, L. C. Alves, J. Mirão, L. Dias, A. M. Lima, V. S. Muralha, and MF Macedo. "Characterization of the glaze and in-glaze pigments of the nineteenth-century relief tiles from the Pena National Palace, Sintra, Portugal." Applied Physics A: Materials Science and Processing. 122.7 (2016): 1-10. Abstract

© 2016, Springer-Verlag Berlin Heidelberg.The glaze and in-glaze pigments of the historical nineteenth-century glazed tiles from the Pena National Palace (Sintra, Portugal) were characterized using a multi-analytical approach. Chemical composition and microstructural characterization were ascertained by µ-PIXE, µ-Raman, optical microscopy and VP-SEM–EDS. The manufacturing technique and colour palette in these tiles were found to be close to the ceramic pigments used in traditional majolica. The blue and purple colours derive from cobalt oxide and manganese oxide, respectively. A mixture of Pb–Sn–Sb yellow with cobalt oxide and iron oxide was used for green and dark yellow, respectively, while grey tonalities consist of a complex mixture of cobalt oxide, manganese oxide and Pb–Sn–Sb yellow in different proportions. Results obtained allowed the determination of the oxides and elements used in pigments as well as production techniques, resorting to traditional majolica manufacture, although the tiles were produced by the end of the nineteenth century.

Kullberg, A. T. G., A. A. S. Lopes, J. P. B. Veiga, M. M. R. A. Lima, and R. C. C. Monteiro. "Formation and crystallization of zinc borosilicate glasses: Influence of the ZnO/B2O3." Journal of Non-Crystalline Solids. 441 (2016): 79-85. Abstract

© 2016 Elsevier B.V. All rights reserved.Different glasses based on the ZnO-B2O3-SiO2 system, with a ZnO content ≥ 60 mol{%} and a fixed SiO2 content (20 mol{%}), were synthesised using a melt-quenching method. Glass samples with zinc oxide concentrations as high as 65 mol{%} were prepared successfully without deteriorating the glass-forming ability. The glass samples were submitted to controlled heat-treatments, and the effect of the ZnO/B2O3 molar ratio on the formation of crystalline phases within the glass matrix was investigated by means of differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). DTA results indicated that the glass transition and the onset crystallization temperatures of the studied glasses tended to increase with the increment on the ZnO/B2O3 ratio. XRD data showed that the zinc binary crystalline phases, willemite (Zn2SiO4), a zinc orthosilicate, and zinc borate (Zn3B2O6) could be present in the crystallized glasses, depending on the heat-treatment conditions. The formation of willemite was promoted by an increasing ZnO/B2O3 ratio. Microstructural observations performed by SEM indicated that under controlled experimental parameters (glass composition, heat-treatment temperature and time) the precipitation of nanocrystals within the glass matrix can be achieved, resulting in transparent and translucent willemite glass-ceramics.

Coutinho, M. L., A. Z. Miller, M. A. Rogerio-Candelera, J. Mirão, L. Cerqueira Alves, JP Veiga, H. Águas, S. Pereira, A. Lyubchyk, and MF Macedo. "An integrated approach for assessing the bioreceptivity of glazed tiles to phototrophic microorganisms." Biofouling. 32.3 (2016): 243-259. Abstract

© 2016 Taylor {&} Francis.A laboratory-based methodology was designed to assess the bioreceptivity of glazed tiles. The experimental set-up consisted of multiple steps: manufacturing of pristine and artificially aged glazed tiles, enrichment of phototrophic microorganisms, inoculation of phototrophs on glazed tiles, incubation under optimal conditions and quantification of biomass. In addition, tile intrinsic properties were assessed to determine which material properties contributed to tile bioreceptivity. Biofilm growth and biomass were appraised by digital image analysis, colorimetry and chlorophyll a analysis. SEM, micro-Raman and micro-particle induced X-ray emission analyses were carried out to investigate the biodeteriorating potential of phototrophic microorganisms on the glazed tiles. This practical and multidisciplinary approach showed that the accelerated colonization conditions allowed different types of tile bioreceptivity to be distinguished and to be related to precise characteristics of the material. Aged tiles showed higher bioreceptivity than pristine tiles due to their higher capillarity and permeability. Moreover, biophysical deterioration caused by chasmoendolithic growth was observed on colonized tile surfaces.

2014
Figueiredo, Maria-Ondina, Teresa P. Silva, Joao P. Veiga, Maria-Joao Batista, Eduardo Salas-Colera, and Daniel P. de Oliveira. "Selenium Speciation in Waste Materials From an Exhausted Iberian Pyrite Belt Mine." Journal of Materials Science Research. 3.4 (2014): p22. Abstract

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Sa, Sofia, Manoj B. Gawande, Alexandre Velhinho, Joao Pedro Veiga, Nenad Bundaleski, Joao Trigueiro, Alexander Tolstogouzov, Orlando M. N. D. Teodoro, Radek Zboril, Rajender S. Varma, and Paula S. Branco. "Magnetically recyclable magnetite-palladium (Nanocat-Fe-Pd) nanocatalyst for the Buchwald-Hartwig reaction." Green Chemistry. 16 (2014): 3494-3500. AbstractWebsite
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Coutinho, M. L., V. S. F. Muralha, J. Mirao, and JP Veiga. "Non-destructive characterization of oriental porcelain glazes and blue underglaze pigments using mu-EDXRF, mu-Raman and VP-SEM." Applied Physics a-Materials Science & Processing. 114 (2014): 695-703. Abstract
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2013
Lima, M. M. R. A., L. F. C. Braz, R. C. C. Monteiro, JP Veiga, AMP Pinto, and AS Pouzada. "Effect of Phosphogypsum on the Clinkerization Temperature of Portland Cement Clincker." Advanced Materials Forum Vi, Pts 1 and 2. 730-732 (2013): 94-99. Abstract
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Veiga, JP. "Molybdenite as a Rhenium Carrier: First Results of a Spectroscopic Approach Using Synchrotron Radiation." Journal of Minerals and Materials Characterization and Engineering (2013). AbstractWebsite
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Figueiredo, MO, TP Silva, JP Veiga, AMP Pinto, and AS Pouzada. "Natural Nanomaterials: Reappraising the Elusive Structure of the Nano-sized Mineral Ferrihydrite through X-Ray Absorption Spectroscopy at the Iron K-Edge." Advanced Materials Forum Vi, Pts 1 and 2. 730-732 (2013): 931-935. Abstract
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Elisa, M., B. A. Sava, I. C. Vasiliu, R. C. C. Monteiro, JP Veiga, L. Ghervase, I. Feraru, and R. Iordanescu. "Optical and structural characterization of samarium and europium-doped phosphate glasses." Journal of Non-Crystalline Solids. 369 (2013): 55-60. Abstract
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Santos, R., J. Loureiro, A. Nogueira, E. Elangovan, JV Pinto, JP Veiga, T. Busani, E. Fortunato, R. Martins, and I. Ferreira. "Thermoelectric properties of V2O5 thin films deposited by thermal evaporation." Applied Surface Science. 282 (2013): 590-594. Abstract
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2012
Perdigao, Jorge, Ana M. Pinto, Regina C. C. Monteiro, Francisco M. BRAZ FERNANDES, Pedro Laranjeira, and Joao P. Veiga. "Degradation of dental ZrO2-based materials after hydrothermal fatigue. Part I: XRD, XRF, and FESEM analyses." Dental Materials Journal. 31 (2012): 256-265. Abstract
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Monteiro, Regina C. C., Andreia A. S. Lopes, Maria M. A. Lima, Joao P. Veiga, Rui JC Silva, Carlos J. Dias, Erika J. R. Davim, and Maria H. V. Fernandes. "Sintering, Crystallization, and Dielectric Behavior of Barium Zinc Borosilicate GlassesuEffect of Barium Oxide Substitution for Zinc Oxide." Journal of the American Ceramic Society. 95 (2012): 3144-3150. Abstract
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Figueiredo, MO, TP Silva, and JP Veiga. "A XANES study of cobalt speciation state in blue-and-white glazes from 16th to 17th century Chinese porcelains." Journal of Electron Spectroscopy and Related Phenomena. 185 (2012): 97-102. Abstract
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2010
Figueiredo, MO, TP Silva, and JP Veiga. "The blue of iron in mineral pigments: a Fe K-edge XANES study of vivianite." Applied Physics a-Materials Science & Processing. 99 (2010): 357-361. Abstract
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Ciocan, Anisoara, Florentino Potecasu, and Joao Pedro Veiga. "CHARACTERISTICS OF THE BLAST FURNACE DUST IN ACCORDANCE WITH THE CONDITIONS IMPOSED BY THE VALORISATION SOLUTION." Metalurgia International. 15 (2010): 85-90. Abstract
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2008
Figueiredo, MO, TP Silva, and JP Veiga. "Analysis of degradation phenomena in ancient, traditional and improved building materials of historical monuments." Applied Physics a-Materials Science & Processing. 92 (2008): 151-154. Abstract
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