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2013
Ferreira, JL, Avila MJ, Melo MJ, Ramos AM.  2013.  Early aqueous dispersion paints: Portuguese artists' use of polyvinyl acetate, 1960s-1990s. Studies in Conservation. 58:211-225., Number 3 AbstractWebsite
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Neves, CS, Granadeiro CM, Cunha-Silva L, Ananias D, Gago S, Feio G, Carvalho PA, Eaton P, Balula SS, Pereira E.  2013.  Europium Polyoxometalates Encapsulated in Silica Nanoparticles Characterization and Photoluminescence Studies. European Journal of Inorganic Chemistry. :2877-2886., Number 16 AbstractWebsite
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Neves, CS, Granadeiro CM, Cunha-Silva L, Ananias D, Gago S, Feio G, Carvalho PA, Eaton P, Balula SS, Pereira E.  2013.  Europium Polyoxometalates Encapsulated in Silica Nanoparticles Characterization and Photoluminescence Studies. European Journal of Inorganic Chemistry. :2877-2886., Number 16 AbstractWebsite

The incorporation of europium polyoxometalates into silica nanoparticles can lead to a biocompatible nanomaterial with luminescent properties suitable for applications in biosensors, biological probes, and imaging. Keggin-type europium polyoxometalates Eu(PW11)x (x = 1 and 2) with different europium coordination environments were prepared by using simple methodologies and no expensive reactants. These luminescent compounds were then encapsulated into silica nanoparticles for the first time through the water-in-oil microemulsion methodology with a nonionic surfactant. The europium polyoxometalates and the nanoparticles were characterized by using several techniques [FTIR, FT-Raman, 31P magic angle spinning (MAS) NMR, and TEM/energy-dispersive X-ray spectroscopy (TEM-EDS), AFM, dynamic light scattering (DLS), and inductively coupled plasma MS (ICP-MS) analysis]. The stability of the material and the integrity of the europium compounds incorporated were also examined. Furthermore, the photoluminescence properties of the Eu(PW11)x@SiO2 nanomaterials were evaluated and compared with those of the free europium polyoxometalates. The silica surface of the most stable nanoparticles was successfully functionalized with appropriate organosilanes to enable the covalent binding of oligonucleotides.

Petrov, V, Gavara R, Dangles O, Al Bittar S, Mora-Soumille N, Pina F.  2013.  A flash photolysis and stopped-flow spectroscopy study of 3 ',4 '-dihydroxy-7-O-beta-D-glucopyranosyloxyflavylium chloride, an anthocyanin analogue exhibiting efficient photochromic properties. Photochemical & Photobiological Sciences. 12:576-581., Number 3 AbstractWebsite
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Aguilo, E, Gavara R, Lima JC, Llorca J, Rodriguez L.  2013.  From Au(I) organometallic hydrogels to well-defined Au(0) nanoparticles. Journal of Materials Chemistry C. 1:5538-5547., Number 35 Abstract
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Oliveira, FS, Pereiro AB, Araujo JM, Bernardes CE, Canongia Lopes JN, Todorovic S, Feio G, Almeida PL, Rebelo LP, Marrucho IM.  2013.  High ionicity ionic liquids (HIILs): comparing the effect of ethylsulfonate and ethylsulfate anions. Phys Chem Chem Phys. 15:18138-47., Number 41 AbstractWebsite

The subject of ionicity has been extensively discussed in the last decade, due to the importance of understanding the thermodynamic and thermophysical behaviour of ionic liquids. In our previous work, we established that ionic liquids' ionicity could be improved by the dissolution of simple inorganic salts in their milieu. In this work, a comparison between the thermophysical properties of two binary systems of ionic liquid + inorganic salt is presented. The effect of the ammonium thiocyanate salt on the ionicity of two similar ionic liquids, 1-ethyl-3-methylimidazolium ethylsulfonate and ethylsulfate, is investigated in terms of the related thermophysical properties, such as density, viscosity and ionic conductivity in the temperature range 298.15-323.15 K. In addition, spectroscopic (NMR and Raman) and molecular dynamic studies were conducted in order to better understand the interactions that occur at a molecular level. The obtained results reveal that although the two anions of the ionic liquid exhibit similar chemical structures, the presence of one additional oxygen in the ethylsulfate anion has a major impact on the thermophysical properties of the studied systems.

Gomes, L, Marques A, Branco A, Araujo J, Simoes M, Cardoso S, Silva F, Henriques I, Laia CAT, Costa C.  2013.  IZO deposition by RF and DC sputtering on paper and application on flexible electrochromic devices. Displays. 34:326-333., Number 4 AbstractWebsite
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Pereira, C, Busani T, Branco LC, Joosten I, Anca Sandu IC.  2013.  Nondestructive Characterization and Enzyme Cleaning of Painted Surfaces: Assessment from the Macro to Nano Level. Microscopy and Microanalysis. 19:1632-1644., Number 6 AbstractWebsite
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Kasthurirangan, S, Saha JK, Agnihotri AN, Bhattacharyya S, Misra D, Kumar A, Mukherjee PK, Santos JP, Costa AM, Indelicato P, Mukherjee TK, Tribedi LC.  2013.  Observation of 2p3 d (1Po)→ 1s3d (1De) Radiative Transition in He-like Si, S, and Cl Ions. Physical Review Letters. 111:243201. AbstractWebsite
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Velasco, LF, Maurino V, Laurenti E, Fonseca IM, Lima JC, Ania CO.  2013.  Photoinduced reactions occurring on activated carbons. A combined photooxidation and ESR study. Applied Catalysis a-General. 452:1-8. Abstract
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Szabo, CI, Amaro P, Guerra M, Schlesser S, Gumberidze A, Santos JP, Indelicato P.  2013.  Reference free, high-precision measurements of transition energies in few electron argon ions. AIP Conf. Proc.. 1525(McDaniel, Floyd D, Doyle, Barney L, Glass, Gary A, Wang, Yongqiang, Eds.).:68-72., Number 1: AIP 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.

Garcia-Estevez, I, Gavara R, Alcalde-Eon C, Rivas-Gonzalo JC, Quideau S, Teresa Escribano-Bailon M, Pina F.  2013.  Thermodynamic and Kinetic Properties of a New Myrtillin-Vescalagin Hybrid Pigment. Journal of Agricultural and Food Chemistry. 61:11569-11578., Number 47 AbstractWebsite
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Sousa, A, Petrov V, Araujo P, Mateus N, Pina F, de Freitas V.  2013.  Thermodynamics, Kinetics, and Photochromism of Oaklins: A Recent Family of Deoxyanthocyanidins. Journal of Physical Chemistry B. 117:1901-1910., Number 6 AbstractWebsite
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Geng, Y, Almeida PL, Feio GM, Figueirinhas JL, Godinho MH.  2013.  Water-Based Cellulose Liquid Crystal System Investigated by Rheo-NMR. Macromolecules. 46:4296-4302., Number 11 AbstractWebsite

Water-based cellulose cholesteric liquid crystalline phases at rest can undergo structural changes induced by shear flow. This reflects on the deuterium spectra recorded when the system is investigated by rheo-nuclear magnetic resonance (rheo-NMR) techniques. In this work, the model system hydroxypropylcellulose (HPC)+water is revisited using rheo-NMR to clarify unsettled points regarding its behavior under shear and in relaxation. The NMR spectra allow the identification of five different stable ordering states, within shear and relaxation, which are well integrated in a mesoscopic picture of the system's structural evolution under shear and relaxation. This picture emerging from the large body of studies available for this system by other experimental techniques, accounts well for the NMR data and is in good agreement with the three distinct regions of steady shear flow recognized for some lyotropic LC polymers. Shear rates in between 0.1 and 1.0 s(-1) where investigated using a Taylor-Couette flow and deuterated water was used as solvent for the deuterium NMR (DNMR) analysis.

Alves, RD, Rodrigues L\'ısaC, Andrade JR, Fernandes M, Pinto JV, Pereira L\'ıs, Pawlicka A, Martins R, Fortunato E, {de Zea Bermudez} V, Silva MM.  2013.  {Gelatin n Zn(CF 3 SO 3 ) 2 Polymer Electrolytes for Electrochromic Devices}. Electroanalysis. 25:1483\{$\backslash$textendash\}1490., Number 6 AbstractWebsite

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2012
Conde, J, Ambrosone A, Sanz V, Hernandez Y, Marchesano V, Tian F, Child H, Berry {CC }, Ibarra R}{M, Baptista {PV}, Tortiglione C, {de la Fuente} {JM }.  2012.  Design of multifunctional gold nanoparticles for in vitro and in vivo gene silencing, sep. ACS Nano. 6:8316–8324., Number 9: ACS - American Chemical Society Abstract

Over the past decade, the capability of double-stranded RNAs to interfere with gene expression has driven new therapeutic approaches. Since small interfering RNA (siRNAs, 21 base pair double-stranded RNA) was shown to be able to elicit RNA interference (RNAi), efforts were directed toward the development of efficient delivery systems to preserve siRNA bioactivity throughout the delivery route, from the administration site to the target cell. Here we provide evidence of RNAi triggering, specifically silencing c-myc protooncogene, via the synthesis of a library of novel multifunctional gold nanoparticles (AuNPs). The efficiency of the AuNPs is demonstrated using a hierarchical approach including three biological systems of increasing complexity: in vitro cultured human cells, in vivo invertebrate (freshwater polyp, Hydra), and in vivo vertebrate (mouse) models. Our synthetic methodology involved fine-tuning of multiple structural and functional moieties. Selection of the most active functionalities was assisted step-by-step through functional testing that adopted this hierarchical strategy. Merging these chemical and biological approaches led to a safe, nonpathogenic, self-tracking, and universally valid nanocarrier that could be exploited for therapeutic RNAi.

Amaro, P, Fratini F, Fritzsche S, Indelicato P, Santos JP, Surzhykov A.  2012.  Parametrization of the angular correlation and degree of linear polarization in two-photon decays of hydrogenlike ions, Oct. Physical Review A. 86:042509. AbstractWebsite

The spontaneous two-photon emission in hydrogenlike ions is investigated within the framework of second- order perturbation theory and Dirac’s equation. Special attention is paid to the angular correlation of the emitted photons as well as to the degree of linear polarization of one of the two photons, if the second is just observed under arbitrary angles. Expressions for the angular correlation and the degree of linear polarization are expanded in powers of cosine functions of the two-photon opening angle, whose coefficients depend on the atomic number and the energy sharing of the emitted photons. The effects of including higher (electric and magnetic) multipoles upon the emitted photon pairs beyond the electric-dipole approximation are also discussed. Calculations of the coefficients are performed for the transitions 2s1/2 → 1s1/2, 3d3/2 → 1s1/2, and 3d5/2 → 1s1/2, along the entire hydrogen isoelectronic sequence (1

Safari, L, Amaro P, Fritzsche S, Santos JP, Tashenov S, Fratini F.  2012.  Relativistic polarization analysis of Rayleigh scattering by atomic hydrogen, Oct. Physical Review A. 86:043405. AbstractWebsite

A relativistic analysis of the polarization properties of light elastically scattered by atomic hydrogen is performed, based on the Dirac equation and second-order perturbation theory. The relativistic atomic states used for the calculations are obtained by making use of the finite basis set method and are expressed in terms of B splines and B polynomials. We introduce two experimental scenarios in which the light is circularly and linearly polarized, respectively. For each of these scenarios, the polarization-dependent angular distribution and the degrees of circular and linear polarization of the scattered light are investigated as a function of scattering angle and photon energy. Analytical expressions are derived for the polarization-dependent angular distribution which can be used for scattering by both hydrogenic as well as many-electron systems. Detailed computations are performed for Rayleigh scattering by atomic hydrogen within the incident photon energy range 0.5 to 5 keV. Particular attention is paid to the effects that arise from higher (nondipole) terms in the expansion of the electron-photon interaction.

Amado, M, Lucas V.  2012.  Advantages of the Certification of Sustainable Construction, May 2012. BSA . , Porto: Minho University
Amado, M, Ganhão A.  2012.  Sustainable Construction: Energy Efficiency in Residential Buildings, May 2012. BSA. , Porto: Minho University
Safari, L, Amaro P, Fritzsche S, Santos JP, Fratini F.  2012.  Relativistic total cross section and angular distribution for Rayleigh scattering by atomic hydrogen, May. Physical Review A. 85:043406., Number 4 AbstractWebsite

We study the total cross section and angular distribution in Rayleigh scattering by hydrogen atom in the ground state, within the framework of Dirac relativistic equation and second-order perturbation theory. The relativistic states used for the calculations are obtained by making use of the finite basis-set method and expressed in terms of B splines and B polynomials. We pay particular attention to the effects that arise from higher (nondipole) terms in the expansion of the electron-photon interaction. It is shown that the angular distribution of scattered photons, while symmetric with respect to the scattering angle θ=90∘ within the electric dipole approximation, becomes asymmetric when higher multipoles are taken into account. The analytical expression of the angular distribution is parametrized in terms of Legendre polynomials. Detailed calculations are performed for photons in the energy range 0.5 to 10 keV. When possible, results are compared with previous calculations.

Sanz, V, Conde J, Ambrosone A, Hernandez Y, Marchesasno V, Estrada {GG }, Ibarra {MR }, Baptista {PV}, Tian F, Tortiglione C, {de la Fuente} {JM }.  2012.  Multifunctional gold nanoparticles for gene silencing, mar. Abstracts Of Papers Of The American Chemical Society. 243: ACS - American Chemical Society Abstract
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Amaro, P, Schlesser S, Guerra M, Le Bigot E-O, Isac J-M, Travers P, Santos JP, Szabo C, Gumberidze A, Indelicato P.  2012.  Absolute Measurement of the Relativistic Magnetic Dipole Transition Energy in Heliumlike Argon, Jul. Physical Review Letters. 109:043005. AbstractWebsite

The 1s2s 3S1 - 1s2 1S0 relativistic magnetic dipole transition in heliumlike argon, emitted by the plasma of an electron-cyclotron resonance ion source, has been measured using a double-flat crystal x-ray spectrometer. Such a spectrometer, used for the first time on a highly charged ion transition, provides absolute (reference-free) measurements in the x-ray domain. We find a transition energy of 3104.1605(77) eV (2.5 ppm accuracy). This value is the most accurate, reference-free measurement done for such a transition and is in good agreement with recent QED predictions.

c}alo Doria, G{\c, Conde J, Veigas B, Giestas L, Almeida C, c}ão MA{\c, Rosa J, Baptista {PV}.  2012.  Noble metal nanoparticles for biosensing applications, feb. Sensors. 12:1657–1687., Number 2: MDPI - Multidisciplinary Digital Publishing Institute Abstract

In the last decade the use of nanomaterials has been having a great impact in biosensing. In particular, the unique properties of noble metal nanoparticles have allowed for the development of new biosensing platforms with enhanced capabilities in the specific detection of bioanalytes. Noble metal nanoparticles show unique physicochemical properties (such as ease of functionalization via simple chemistry and high surface-to-volume ratios) that allied with their unique spectral and optical properties have prompted the development of a plethora of biosensing platforms. Additionally, they also provide an additional or enhanced layer of application for commonly used techniques, such as fluorescence, infrared and Raman spectroscopy. Herein we review the use of noble metal nanoparticles for biosensing strategies-from synthesis and functionalization to integration in molecular diagnostics platforms, with special focus on those that have made their way into the diagnostics laboratory.

Cordas, CM, Raleiras P, Auchere F, Moura I, Moura JJ.  2012.  Comparative electrochemical study of superoxide reductases, Dec 6. Eur Biophys J. 41:209-215., Number 12
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