A carregar...
Projeto de investigação
Laboratory for Instrumentation, Biomedical Engineering and Radiation Physics
Financiador
Autores
Publicações
A painter in the shadow
Publication . Antunes, Vanessa; Serrão, Vítor; Valadas, Sara; Candeias, António; Mirão, José; Cardoso, Ana; Manso, Marta; Carvalho, Maria L.; LIBPhys-UNL; DF – Departamento de Física; MDPI - Multidisciplinary Digital Publishing Institute
The painting collection of Santa Casa da Misericórdia da Lourinhã is amongst Portugal’s most notable and scarcely best-known cultural heritage. The artistic interest of this pictorial group, besides the advanced state of degradation of a number of the paintings, together with the ruined circumstances of the building accommodating the collection, today in reconstruction, were the key reasons for this study. Thermo-hygrometric measurements were carried out. A multianalytical methodology incorporating micro-X-ray diffraction (µ-XRD), energy-dispersive X-ray fluorescence spectroscopy (EDXRF), scanning electron microscopy–energy dispersive spectroscopy (SEM–EDS), micro-Raman spectroscopy (µ-Raman), micro-Fourier transform infrared spectroscopy (µ-FTIR) has been followed for the study. These analyses were complemented by infrared photography (IRP) and reflectography (IRR), allowing the study of the underdrawing technique. The results of this study were compared with previous ones of the painter’s workshop and important distinctions and similarities were found within the materials and techniques used. This analysis methodology on materials contributes to safeguarding and the ensuing community awareness of this cultural heritage in danger.
Mineral Monitorization in Different Tissues of Solanum tuberosum L. during Calcium Biofortification Process
Publication . Coelho, Ana Rita F.; Lidon, Fernando Cebola; Pessoa, Cláudia Campos; Daccak, Diana; Luís, Inês Carmo; Marques, Ana Coelho; Ramalho, José Cochicho; Semedo, José Manuel N.; Silva, Maria Manuela; Pais, Isabel P.; Brito, Maria Graça; Kullberg, José Carlos; Legoinha, Paulo; Simões, Maria; Scotti-Campos, Paula; Pessoa, Maria Fernanda; Reboredo, Fernando Henrique; DCT - Departamento de Ciências da Terra; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; MDPI - Multidisciplinary Digital Publishing Institute
Calcium is one of the 16 essential elements for plants, being required as Ca2+ and being involved in several fundamental processes (namely, in the stability and integrity of the cell wall, the development of plant tissue, cell division, and in stress responses). Moreover, Ca plays an important role in potato production. In this context, this study aimed to monitor the culture development (in situ and using an unmanned aerial vehicle (UAV)) and the mineral content of four essential elements (Ca, P, K, and S) in different organs of Solanum tuberosum L. (roots, stems, leaves, and tubers) during a calcium biofortification process, carried out with two types of solutions (CaCl2 and Ca-EDTA) with two concentrations (12 and 24 kg∙ha−1). The calcium content generally increased in the S. tuberosum L. organs of both varieties and showed, after the last foliar application, an increase in Ca content that varied between 5.7–95.6% and 20.7–33%, for the Picasso and Agria varieties, respectively. The patterns of accumulation in both varieties during the biofortification process were different between the variety and mineral element. Regarding the quality analysis carried out during the development of the tubers, only the Agria variety was suitable for industrial processing after the last foliar application.
Enrichment of Grapes with Zinc-Efficiency of Foliar Fertilization with ZnSO4 and ZnO and Implications on Winemaking
Publication . Daccak, Diana; Lidon, Fernando C.; Pessoa, Cláudia Campos; Luís, Inês Carmo; Coelho, Ana Rita F.; Marques, Ana Coelho; Ramalho, José C.; Silva, Maria José; Rodrigues, Ana Paula; Guerra, Mauro; Leitão, Roberta G.; Campos, Paula Scotti; Pais, Isabel P.; Semedo, José N.; Silva, Maria Manuela; Kullberg, José Carlos; Brito, Maria; Galhano, Carlos; Legoinha, Paulo; Pessoa, Maria Fernanda; Simões, Manuela; Reboredo, Fernando H.; DCT - Departamento de Ciências da Terra; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; LIBPhys-UNL; DF – Departamento de Física; MDPI - Multidisciplinary Digital Publishing Institute
Grapes and wine are widely consumed in the world, yet their mineral content can be influenced by many factors such as the mineral composition of soils, viticulture practices and environmental conditions. In this context, considering the importance of Zn in the human physiology, the enrichment of Moscatel and Castelão grapes (white and red variety, respectively) with this nutrient prompted this study; further assessment of tissue deposition and some implications for wine production. Using two foliar fertilizers (ZnO or ZnSO4, at 150, 450 and 900 g ha−1), decreases in net photosynthesis and stomatal conductance occurred in both varieties, suggesting that the physiological threshold of Zn toxicity was reached without visible symptoms. Following foliar spraying with both fertilizers, the content of Zn in leaves of the Castelão and Moscatel varieties showed higher values in all treatments relative to the control. Moreover, in grapes this tendency occurred only in Castelão. Concerning Cu, Fe, Ca, K, S and P, some significant differences also happened in leaves and grapes among treatments. At harvest, the indexes of Zn enrichment in grapes increased between 2.14-and 8.38-fold and between 1.02-and 1.44-fold in Castelão and Moscatel varieties, respectively. Zinc in the dried skin of Castelão only increased with ZnO and ZnSO4 sprayed at 900 g ha−1 (ca. 2.71-and 1.5-fold relative to the control, respectively), but in Moscatel a clear accumulation trend could not be found. The dry weight of grapes ranged (in %) between 16 and 23 (but did not vary significantly among treatments of each variety or in each treatment between varieties), and total soluble solids (e.g., mainly soluble sugars and proteins) and color parameters showed some significant variations. Through winemaking, the contents of Zn increased in both varieties (1.34-and 3.57-fold, in Castelão and Moscatel, respectively) and in all treatments, although non-significantly in Castelão. It is concluded that, to increase the contents of Zn in grapes without reaching the threshold of toxicity, ZnO or ZnSO4 can be used for foliar spraying of Castelão and Moscatel varieties until 900 g ha −1 And that winemaking augments the level of this nutrient.
High precision tests of QED Measurement of the alpha-particle and helion rms charge radius and the transition energies in highly-charged ions
Publication . Machado, Jorge Felizardo Dias Cunha; Santos, José; Indelicato, Paul
This work aims to provide insight on Bound-State Quantum-Electrodynamics
(BSQED) by experimental fundamentals high-precision tests in exotic states of
matter. Although BSQED and the relativistic many-body problem have been undergoing
important progress, there are still some issues that require the increase
of the number and accuracy of experimental fundamental tests.
The first part of this work was done within the framework of the recent experiment
in muonic helium ions ( 4He+ and 3He+) by the CREMA collaboration.
This experiment, aims to provide new accurate values for the root-mean-square
(rms) charge radii of the helium isotopes nuclei that are extracted from the measurement of the Lamb Shift, i.e., the measurement of the energy difference between the 2S 2P states. With the goal of measuring the transition energies with an accuracy of at least 50 ppm, the rms charge radii of the helium isotopes will be determined with an uncertainty of 0.03%, a factor of ten more precise than previous
results obtained from electron scattering.
The second part of this work aims the high-precision measurement of x-ray
transitions in Highly-Charged Ions (HCI) using a Double-Crystal Spectrometer
(DCS). These ions were produced in the plasma of an Electron-Cyclotron Resonance
Ion Source (ECRIS). This kind of spectrometer is able not only to provide
high-precision measurements but also reference-free measurements, without reference
to any theoretical or experimental energy. Four transitions energies from
n = 2!n = 1 have been measured in an argon plasma in three different charge
states, He-, Be- and Li-like, with an accuracy of better than 3 ppm. Besides the energies, the natural width of each transition has also been experimentally obtained.
The obtained results are in excellent agreement with the most recent theoretical
calculations.
O caderno de esboços de um artista: O antigo retábulo da Sé de Goa (India) atribuído ao pintor Garcia Fernandes - influências iconográficas, estilísticas e estudo do desenho subjacente
Publication . Antunes, Vanessa; Serrão, Vitor; Candeias, António; Mirão, José; Valadas, Sara; Carvalho, Maria Luísa; LIBPhys-UNL; DF – Departamento de Física; Associação Profissional de Conservadores-Restauradores de Portugal (ARP)
Goa Cathedral former altarpiece, attributed to Garcia Fernandes and made around 1538, is one of the oldest western pictorial works in India. It is a work of great importance in the establishment of the conquest of Goa by the Portuguese but also for understanding the influence of Portuguese painting overseas. Goa Cathedral former altarpiece is revealed as a crucial study source of Garcia Fernandes' creative process. There is evidence in the vigorous underdrawing of these paintings, of the existence of different types of drawing, as well as abandoned iconographic themes, or formal alterations of compositions. The iconographic and stylistic study evidences north and south-European influences in the choice and representation of the themes around the Martírio de Santa Catarina. In the present study, this work is compared in the making of the underdrawing with other works attributed to Garcia Fernandes.
Unidades organizacionais
Descrição
Palavras-chave
Contribuidores
Financiadores
Entidade financiadora
Fundação para a Ciência e a Tecnologia
Programa de financiamento
6817 - DCRRNI ID
Número da atribuição
UID/FIS/04559/2013