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2013
Guerra, M., P. Amaro, C. I. Szabo, A. Gumberidze, P. Indelicato, and J. P. Santos. "Analysis of the charge state distribution in an ECRIS Ar plasma using high-resolution x-ray spectra." Journal of Physics B: Atomic, Molecular and Optical Physics. 46 (2013): 065701. AbstractWebsite

In this work, we obtained a charge state distribution inside an Ar plasma produced by an electron–cyclotron-resonance ion source. The processes that lead to the observed lines in x-ray spectra are identified and included in the simulated x-ray spectrum. The geometrical constraints of the flat double crystal spectrometer, used to measure the x-ray spectrum, are investigated as they are crucial for correctly obtaining the ion densities from the observed transition amplitudes. Multiple electron impact ionization is included, and a realistic electron velocity distribution is taken into account. The charge state distribution of the Ar ions is compared to measured extracted ionic currents.

Ana, Baptista, Ferreira Isabel, and Borges João Paulo. "Cellulose-Based Bioelectronic Devices." Cellulose: Medical, Pharmaceutical and Electronic Applications. Eds. Theo van de Ven, and Louis Godbout. INTECH, 2013. 67-82. Abstract
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Ana, Baptista, Ferreira Isabel, and Borges João Paulo. "Cellulose-based composite Systems for Biomedical Applications." Biomass-based Biocomposites. Eds. Vijay Kumar Thakur, and Amar Singh Singha. Smithers Rapra, 2013. 47-60. Abstract
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AC, Baptista, Ferreira I, and Borges JP. "Electrospun Fibers in Composite Materials for Medical Applications." Journal of Composites and Biodegradable Polymers. 1.1 (2013): 56-65. Abstract

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MB, Gawande, Rathi AK, Branco PS, Potewar TM, Velhinho A, Nogueira ID, Tolstogouzov A, Ghumman CAA, and Teodoro OMND. "Nano-MgO-ZrO2 Mixed Metal oxides: Extensive characterization by SIMS and application in the reduction of carbonyl compounds and in multicomponent reactions." 3 (2013): 3611-3617. Abstract
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Ana, Baptista, Soares Paula, Ferreira Isabel, and Borges João Paulo. "Nanofibers and Nanoparticles in Biomedical Applications." Bioengineered Nanomaterials. Ed. Ashutosh Tiwari Atul Tiwari. CRC Press, 2013. 93-123. Abstract
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Silva, Ricardo, Duarte Viúla M. Faria, Pinho A. Ramos, and Micael Inácio. "A physical approach for considering how anchorage head size influences the punching capacity of slabs strengthened with vertical steel bolts." Structural Concrete. 14 (2013): 389-400. AbstractWebsite

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Guerra, M., P. Amaro, C. I. Szabo, A. Gumberidze, P. Indelicato, and J. P. Santos. "Analysis of the charge state distribution in an ECRIS Ar plasma using high-resolution x-ray spectra." Journal of Physics B: Atomic, Molecular and Optical Physics. 46 (2013): 065701. AbstractWebsite

In this work, we obtained a charge state distribution inside an Ar plasma produced by an electron–cyclotron-resonance ion source. The processes that lead to the observed lines in x-ray spectra are identified and included in the simulated x-ray spectrum. The geometrical constraints of the flat double crystal spectrometer, used to measure the x-ray spectrum, are investigated as they are crucial for correctly obtaining the ion densities from the observed transition amplitudes. Multiple electron impact ionization is included, and a realistic electron velocity distribution is taken into account. The charge state distribution of the Ar ions is compared to measured extracted ionic currents.

I. Bastos, Oliveira L. B., JP Oliveira, and J. Goes A 1.2 V Low-Noise-Amplifier with Double Feedback for High Gain and Low Noise Figure. Doctoral Conference on Computing, Electrical and Industrial Systems (DoCEIS’2013). Caparica, Portugal: IFIP Advances in Information and Communication Technology, 2013.
I. Bastos, LB. Oliveira, JP. Oliveira, and J. Goes Double Feedforward 0.6 V LNA with High Gain and Low Noise Figure. 20th Int. Conf. Mixed Design of Integrated Circuits and Systems (MIXDES'2013). Gdynia, Poland: IEEE, 2013.
Carrasco, G., Rybarczyk Y., Cardoso T., and Martins I.P. "A serious game for multimodal training of physician novices." 6th International Conference of Education, Research and Innovation. Seville, Spain 2013. copy.pdfposter.pdf
Vieira, E. M. F., S. Levichev, C. J. Dias, R. Igreja, M. Buljan, S. Bernstorff, O. Conde, A. Chahboun, A. G. Rolo, and M. J. M. Gomes. "Charge storage behavior of nanostructures based on SiGe nanocrystals embedded in Al2O3 matrix." European Physical Journal B. 86 (2013). AbstractWebsite
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Vieira, Eliana M. F., Sergey Levichev, Carlos J. Dias, Rui Igreja, Maja Buljan, Sigrid Bernstorff, Olinda Conde, Adil Chahboun, Anabela G. Rolo, and Maria J. M. Gomes. "Charge storage behavior of nanostructures based on SiGe nanocrystals embedded in Al2O3 matrix." European Physical Journal B. 86 (2013). Abstract
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Merino, E. G., P. D. Neves, I. M. Fonseca, F. Danéde, A. Idrissi, C. J. Dias, M. Dionísio, and N. T. Correia. "Detection of two glass transitions on triton X-100 under confinement." Journal of Physical Chemistry C. 117 (2013): 21516-21528. AbstractWebsite
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Neagu, B., E. R. Neagu, R. Igreja, and C. Dias. "Electric Field Distribution Around the Deep Brain Stimulation Electrode Inferred from Dielectric Measurements." Advanced Materials Forum Vi, Pts 1 and 2. Eds. AMP Pinto, and AS Pouzada. Vol. 730-732. Materials Science Forum, 730-732. 2013. 26-31. Abstract
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Neagu, B., E. R. Neagu, R. Igreja, C. Dias, AMP Pinto, and AS Pouzada. "Electric Field Distribution Around the Deep Brain Stimulation Electrode Inferred from Dielectric Measurements." Advanced Materials Forum Vi, Pts 1 and 2. 730-732 (2013): 26-31. Abstract
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Igreja, R., H. Domingos, J. P. Borges, and C. J. Dias. "Enhancing the response of chemocapacitors with electrospun nanofiber films." Materials Science Forum. 730-732 (2013): 197-202. AbstractWebsite
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Igreja, R., H. Domingos, J. P. Borges, C. J. Dias, AMP Pinto, and AS Pouzada. "Enhancing the Response of Chemocapacitors with Electrospun Nanofiber Films." Advanced Materials Forum Vi, Pts 1 and 2. 730-732 (2013): 197-202. Abstract
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Elisa, M. a, B. A. a Sava, I. C. a Vasiliu, R. C. C. b Monteiro, C. R. a Iordanescu, I. D. a Feraru, L. a Ghervase, C. c Tanaselia, M. c Senila, and B. c Abraham. "Investigations on optical, structural and thermal properties of phosphate glasses containing terbium ions." IOP Conference Series: Materials Science and Engineering. Vol. 47. 2013. Abstract

{Aluminophosphate glasses belonging to the Li2O-BaO-Al 2O3- La2O3-P2O 5 system doped with Tb3+ were prepared and investigated. Methods as Induced Coupled Plasma-Mass Spectrometry (ICP-MS), Induced Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) and X-ray diffraction (XRD) have been used to establish the elemental composition of these vitreous materials. The influence of the Tb3+ ions on the optical properties of the phosphate glasses has been investigated in relation with the structural characteristics of the vitreous matrix. The optical behavior has been studied by ultra-violet-visible (UV-Vis) spectroscopy, revealing electronic transitions specific for terbium ions. Fluorescence spectroscopy measurements have been performed by excitation in the UV and visible domains (377 nm and 488 nm) which resulted in the most significant fluorescence peaks in the Vis domain (540 and 547 nm). Structural information via vibration modes were provided by Fourier Transform Infrared (FTIR) absorption spectra in the 400-4000 cm-1 range. Absorption peaks specific for the vitreous phosphate matrix were put in evidence as P-O-P symmetrical and asymmetrical stretching vibration modes, P-O-P bend, PO2- symmetrical and asymmetrical stretching vibration modes

Kasthurirangan, S., J. K. Saha, A. N. Agnihotri, S. Bhattacharyya, D. Misra, A. Kumar, P. K. Mukherjee, J. P. Santos, A. M. Costa, P. Indelicato, T. K. Mukherjee, and L. C. Tribedi. "Observation of 2p3 d (1Po)→ 1s3d (1De) Radiative Transition in He-like Si, S, and Cl Ions." Physical Review Letters. 111 (2013): 243201. AbstractWebsite
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Kasthurirangan, S., J. K. Saha, A. N. Agnihotri, S. Bhattacharyya, D. Misra, A. Kumar, P. K. Mukherjee, J. P. Santos, A. M. Costa, P. Indelicato, T. K. Mukherjee, and L. C. Tribedi. "Observation of 2p3 d (1Po)→ 1s3d (1De) Radiative Transition in He-like Si, S, and Cl Ions." Physical Review Letters. 111 (2013): 243201. AbstractWebsite
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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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Elisa, M. a, B. A. a Sava, I. C. a Vasiliu, R. C. C. b Monteiro, J. P. B. Veiga, L. a Ghervase, I. a Feraru, and R. a Iordanescu. "Optical and structural characterization of samarium and europium-doped phosphate glasses." Journal of Non-Crystalline Solids. 369 (2013): 55-60. AbstractWebsite

The work deals with optical and structural properties of aluminophosphate glasses from Li2O-BaO-Al2O3-La 2O3-P2O5 system containing Sm 3 + and Eu3 + ions. X-ray fluorescence (XRF) has been used to establish the elemental composition of these materials. The influence of Sm3 + and Eu3 + ions on the optical properties of these glasses has been investigated in relation with their structural characteristics. The optical behavior of these materials has been studied by ultra-violet-visible (UV-Vis) spectroscopy, revealing absorption maxima specific to the doping ions. Structural information via vibration modes was provided by Fourier Transform Infrared (FTIR) absorption spectra evidenced as POP symmetrical and asymmetrical stretching vibration modes, POP bend, PO 2- symmetrical and asymmetrical stretching vibration modes, PO stretching vibration mode and POH water absorbance. Raman spectra acquired by 514.5 nm laser excitation disclosed peaks specific to metaphosphate network. Information about the elemental compositional homogeneity of Sm 3 + and Eu3 +-containing glasses as well as about the defects of the doped-glasses is revealed by scanning electron microscopy/energy dispersive spectrometry (SEM/EDS). Fluorescence spectroscopy measurements put in evidence important fluorescence peaks found at 596 nm and 643 nm for Sm 3 + ions in phosphate matrix and 611 nm and 700 nm in the case of Eu3 +-doped glass. © 2013 Elsevier B.V.

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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Szabo, Csilla I., Pedro Amaro, Mauro Guerra, Sophie Schlesser, Alexander Gumberidze, Jose Paulo Santos, and Paul Indelicato. "Reference free, high-precision measurements of transition energies in few electron argon ions." AIP APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY: Twenty-Second International Conference. 1525 (2013): 68-72. AbstractWebsite

The use of a vacuum double crystal spectrometer, coupled to an electron-cyclotron resonance ion source (ECRIS), allows to measure low-energy x-ray transitions energies in highly-charged ions with accuracies of the order of a few parts per million. We have used this installation to measure the 1s2p 1 P1 - 1s2 1 S0 diagram line and the 1s2s 3 S1 - 1s2 1 S0 forbidden M1 transition energies in helium-like argon, the 1s2s2p 2 P j 1s2 2s 2 S1/2 transitions in lithium-like argon and the 1s2s2 2p 1 P1 - 1s2 2s2 1 S0 transition in beryllium-like argon. These transition measurements have accuracies between 2 and 4 ppm depending on the line intensity. Thanks to the excellent agreement between the simulations and the measurements, we were also able to measure the transition width of all the allowed transitions. The results are compared to recent QED and relativistic many-body calculations.