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2016
Cardoso, Pedro, Pedro Amaro, Jose Paulo Santos, Joaquim T. de Assis, and Maria Luisa Carvalho. "Determination of Nickel and Manganese Contaminants in Pharmaceutical Iron Supplements using Energy Dispersive X-ray Fluorescence." Applied Spectroscopy (2016). AbstractWebsite

In this study, we investigate the capability of energy dispersive X-ray fluorescence (EDXF) spectrometry in a triaxial geometry apparatus as a fast and nondestructive determination method of both dominant and contaminant elements in pharmaceutical iron supplements. The following iron supplements brands with their respective active ingredients were analyzed: Neutrofer fólico (iron gylcinate), Anemifer (iron(II) sulfate monohydrate), Noripurum (iron(III)-hydroxide polymaltose complex), Sulferbel (iron(II) sulfate monohydrate), and Combiron Fólico (carbonyl iron). Although we observe a good agreement between the iron content obtained by the present method and that indicated in the supplement's prescribed dose, we observe contamination by manganese and nickel of up to 180 μg and 36 μg, respectively. These contents correspond to 7.2% and 14.4% of the permitted daily exposure of manganese and nickel, respectively, for an average adult individual as determined by the European Medicine Agency (EMEA). The method was successfully validated against the concentrations of several certified reference materials of biological light matrices with similar concentrations of contaminants. Moreover, we also validated our method by comparing the concentrations with those obtained with the inductively coupled plasma-atomic emission technique.

Ito, Y., T. Tochio, H. Ohashi, M. Yamashita, S. Fukushima, M. Polasik, K. Słabkowska, Ł. Syrocki, E. Szymańska, J. Rzadkiewicz, P. Indelicato, J. P. Marques, M. C. Martins, J. P. Santos, and F. Parente. "Kα1,2x-ray linewidths, asymmetry indices, and [KM]shake probabilities in elements Ca to Ge and comparison with theory for Ca, Ti, and Ge." Physical Review A 94 (2016): 042506-11. AbstractWebsite
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Marques, J. P., P. Indelicato, F. Parente, J. M. Sampaio, and J. P. Santos. "Ground-state Landé <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML"><mi>g</mi></math></span> factors for selected ions along the boron isoelectronic sequence." Physical Review A 94 (2016): 042504. AbstractWebsite

Land\'e $g$ factors for the fine-structure $1{s}^{2}2{s}^{2}2p\phantom{\rule{0.16em}{0ex}}^{2}P_{1/2}$ and $^{2}P_{3/2}$ levels in the boron isoelectronic sequence for selected $Z$ values have been calculated using the multiconfiguration Dirac-Fock method with both quantum-electrodynamic and electronic correlation corrections included. All-order Breit and vacuum polarization corrections were included in the calculation, with a fully optimized active set wave function. The results are compared with the available theoretical data, showing a very good agreement.

Sampaio, J. M., T. I. Madeira, M. Guerra, F. Parente, P. Indelicato, J. P. Santos, and J. P. Marques. "Relativistic calculations of K-, L- and M-shell X-ray production cross-sections by electron impact for Ne, Ar, Kr, Xe, Rn and Uuo." Journal of Quantitative Spectroscopy and Radiative Transfer 182 (2016): 87-93. AbstractWebsite

Journal of Quantitative Spectroscopy and Radiative Transfer, 182 + (2016) 87-93. doi:10.1016/j.jqsrt.2016.05.012

Rahangdale, H. V., D. Mitra, P. K. Das, S. De, M. Guerra, J. P. Santos, and S. Saha. "Spectroscopic investigations of L-shell ionization in heavy elements by electron impact." Journal of Quantitative Spectroscopy and Radiative Transfer 174 (2016): 79-87. AbstractWebsite

Journal of Quantitative Spectroscopy and Radiative Transfer, 174 + (2016) 79-87. doi:10.1016/j.jqsrt.2016.01.026

Amaro, Pedro, Filippo Fratini, Laleh Safari, Jorge Machado, Mauro Guerra, Paul Indelicato, and Jose Paulo Santos. "Relativistic evaluation of the two-photon decay of the metastable 1s22s2p 3P0 state in berylliumlike ions with an effective-potential model." Physical Review A 93 (2016): 032502-8. AbstractWebsite

The two-photon $1{s}^{2}2s2p\phantom{\rule{0.16em}{0ex}}{}^{3}{P}_{0}\ensuremath{\rightarrow}1{s}^{2}{s}^{2}\phantom{\rule{0.16em}{0ex}}{}^{1}{S}_{0}$ transition in berylliumlike ions is investigated theoretically within a fully relativistic framework and a second-order perturbation theory. We focus our analysis on how electron correlation, as well as the negative-energy spectrum, can affect the forbidden $E1M1$ decay rate. For this purpose, we include the electronic correlation via an effective local potential and within a single-configuration-state model. Due to its experimental interest, evaluations of decay rates are performed for berylliumlike xenon and uranium. We find that the negative-energy contribution can be neglected at the present level of accuracy in the evaluation of the decay rate. On the other hand, if contributions of electronic correlation are not carefully taken into account, it may change the lifetime of the metastable state by up to 20%. By performing a fully relativistic $jj$-coupling calculation, we find a decrease of the decay rate by two orders of magnitude compared to nonrelativistic $LS$-coupling calculations, for the selected heavy ions.

Sampaio, J. M., M. Guerra, F. Parente, T. I. Madeira, P. Indelicato, J. P. Santos, and J. P. Marques. "Calculations of photo-induced X-ray production cross-sections in the energy range 1–150 keV and average fluorescence yields for Zn, Cd and Hg." Atomic Data and Nuclear Data Tables 111-112 (2016): 67-86. AbstractWebsite

Atomic Data and Nuclear Data Tables, 111-112 (2016) 67-86. doi:10.1016/j.adt.2016.02.001

Ramos, I., I. M. Pataco, M. P. Mourinho, F. Lidon, F. Reboredo, M. F. Pessoa, M. L. Carvalho, J. P. Santos, and M. Guerra. "Elemental mapping of biofortified wheat grains using micro X-ray fluorescence." Spectrochimica Acta Part B: Atomic Spectroscopy 120 (2016): 30-36. AbstractWebsite

Spectrochimica Acta Part B: Atomic Spectroscopy, 120 (2016) 30-36. doi:10.1016/j.sab.2016.03.014

Guerra, M., C. Ferreira, M. L. Carvalho, J. P. Santos, and S. Pessanha. "Distribution of toxic elements in teeth treated with amalgam using μ-energy dispersive X-ray fluorescence." Spectrochimica Acta Part B: Atomic Spectroscopy 122 (2016): 114-117. AbstractWebsite

Spectrochimica Acta Part B: Atomic Spectroscopy, 122 (2016) 114-117. doi:10.1016/j.sab.2016.06.006

Guimarães, D., A. A. Dias, M. Carvalho, M. L. Carvalho, J. P. Santos, F. R. Henriques, F. Curate, and S. Pessanha. "Quantitative determinations and imaging in different structures of buried human bones from the XVIII-XIXth centuries by energy dispersive X-ray fluorescence – Postmortem evaluation." Talanta 155 (2016): 107-115. AbstractWebsite

Talanta, 155 + (2016) 107-115. doi:10.1016/j.talanta.2016.04.028

2015
Santos, J. P., J. P. Marques, M. C. Martins, P. Indelicato, E. P. Benis, T. J. M. Zouros, and F. Parente. "Energy levels, transition rates and lifetimes for Li-like ions with Z≤ 10 in the 1 s2 s( 3S)3ℓ states." Journal of Physics: Conference Series 635 (2015): 052060-2. AbstractWebsite
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Marques, J. P., M. Guerra, F. Parente, J. P. Santos, P. Indelicato, and J. M. Sampaio. "K-shell width, fluorescence yield, and Kβ/ Kαintensity ratio calculation for Fe in the Dirac-Fock approach." Journal of Physics: Conference Series 635 (2015): 092094-2. AbstractWebsite
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Sampaio, J. M., M. Guerra, T. I. Madeira, F. Parente, P. Indelicato, J. P. Santos, and J. P. Marques. "Relativistic calculations of atomic parameters in Ununoctium." Journal of Physics: Conference Series 635 (2015): 092095-2. AbstractWebsite
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Rahangdale, H. V., D. Mitra, M. Guerra, J. P. Santos, and S. Saha. "Subshell resolved inner shell ionization cross-sections of High Z elements by electron impact." Journal of Physics: Conference Series 635 (2015): 052001-2. AbstractWebsite
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Sampaio, J. M., T. I. Madeira, M. Guerra, F. Parente, J. P. Santos, P. Indelicato, and J. P. Marques. "Dirac-Fock calculations of K−, L−, and M-shell fluorescence and Coster-Kronig yields for Ne, Ar, Kr, Xe, Rn, and Uuo." Physical Review A 91 (2015): 052507. AbstractWebsite
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Guerra, M., Th Stöhlker, P. Amaro, J. Machado, and J. P. Santos. "Electron impact ionization cross-sections for few-electron uranium ions." Journal of Physics B: Atomic, Molecular and Optical Physics 48 (2015): 1-5. AbstractWebsite

Journal of Physics B: Atomic, Molecular and Optical Physics, 48(2015) 144027. doi:10.1088/0953-4075/48/14/144027

Safari, L., J. P. Santos, P. Amaro, K. Jankala, and F. Fratini. "Analytical evaluation of atomic form factors: Application to Rayleigh scattering." Journal of Mathematical Physics 56 (2015): 052105-9. AbstractWebsite
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Diepold, Marc, Luis M. P. Fernandes, Jorge Machado, Pedro Amaro, Marwan Abdou-Ahmed, Fernando D. Amaro, Aldo Antognini, François Biraben, Tzu-Ling Chen, Daniel S. Covita, Andreas J. Dax, Beatrice Franke, Sandrine Galtier, Andrea L. Gouvea, Johannes Götzfried, Thomas Graf, Theodor W. Hänsch, Malte Hildebrandt, Paul Indelicato, Lucile Julien, Klaus Kirch, Andreas Knecht, Franz Kottmann, Julian J. Krauth, Yi-Wei Liu, Cristina M. B. Monteiro, Françoise Mulhauser, Boris Naar, Tobias Nebel, François Nez, Jose Paulo Santos, Joaquim M. F. dos Santos, Karsten Schuhmann, Csilla I. Szabo, David Taqqu, João F. C. A. Veloso, Andreas Voss, Birgit Weichelt, and Randolf Pohl. "Improved x-ray detection and particle identification with avalanche photodiodes." Review of Scientific Instruments 86 (2015): 053102-7. AbstractWebsite
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Amaro, Pedro, Filippo Fratini, Laleh Safari, Aldo Antognini, Paul Indelicato, Randolf Pohl, and Jose Paulo Santos. "Quantum interference shifts in laser spectroscopy with elliptical polarization." Physical Review A 92 (2015): 062506-5. AbstractWebsite
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Benis, E. P., S. Doukas, T. J. M. Zouros, P. Indelicato, F. Parente, C. Martins, J. P. Santos, and J. P. Marques. "Evaluation of the effective solid angle of a hemispherical deflector analyser with injection lens for metastable Auger projectile states." Nuclear Inst. and Methods in Physics Research, B 365 (2015): 457-461. AbstractWebsite

Nuclear Inst. and Methods in Physics Research, B, 365 (2015) 457-461. doi:10.1016/j.nimb.2015.07.006

Amaro, Pedro, Beatrice Franke, Julian J. Krauth, Marc Diepold, Filippo Fratini, Laleh Safari, Jorge Machado, Aldo Antognini, Franz Kottmann, Paul Indelicato, Randolf Pohl, and Jose Paulo Santos. "Quantum interference effects in laser spectroscopy of muonic hydrogen, deuterium, and helium-3." Physical Review A 92 (2015): 022514-7. AbstractWebsite
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Guerra, M., J. M. Sampaio, T. I. Madeira, F. Parente, P. Indelicato, J. P. Marques, J. P. Santos, J. Hoszowska, Cl J. Dousse, L. Loperetti, F. Zeeshan, M. Muller, R. Unterumsberger, and B. Beckhoff. "Theoretical and experimental determination of L-shell decay rates, line widths, and fluorescence yields in Ge." Physical Review A 92 (2015): 022507-9. AbstractWebsite
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Guerra, M., P. Amaro, J. Machado, and J. P. Santos. "Single differential electron impact ionization cross sections in the binary-encounter- Bethe approximation for the low binding energy regime." Journal of Physics B: Atomic, Molecular and Optical Physics 48 (2015): 1-9. AbstractWebsite

Journal of Physics B: Atomic, Molecular and Optical Physics, 48(2015) 185202. doi:10.1088/0953-4075/48/18/185202

Guerra, M., S. C. Pé-Leve Santos, A. M. E. Barroso, C. P. S. Fonseca, M. Eloy Cruz, P. Amaro, J. L. Figueirinhas, M. L. Carvalho, and J. P. Santos. "Spatially resolved determination of toxic trace elements in plants of Panasqueira mining region using micro X-ray fluorescence." Microscopy and Microanalysis 21 (2015): 54-55. AbstractWebsite
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