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A novel immobilized Ca0.6Ho0.4MnO3 photocatalyst has been developed with high photocatalytic activity for Rhodamine 6G (Rh6G) photodegradation under visible light irradiation. The nanocrystalline Ca0.6Ho0.4MnO3 films were successfully deposited by RF-magnetron sputtering on unheated quartz glass substrates using Ca0.6Ho0.4MnO3 powder as sputtering target and its photocatalytic functionalities have been explored. The visible-light-responsive photocatalytic activity of Ca0.6Ho0.4MnO3 films was evaluated by the photodegradation of Rh6G aqueous solutions under visible light irradiation. The reusability of Ca0.6Ho0.4MnO3 films on fresh dye samples was studied, showing an efficient reuse, without decreasing the photocatalytic decolorization efficiency. Furthermore, X-ray diffraction of the reused films did not reveal additional phases indicating high photochemical stability of the films even after reusing them in successive runs. The photocatalytic efficiency of the nanocrystalline Ca0.6Ho0.4MnO3 films was further compared with TiO2 films also produced by sputtering and the results revealed a significant improvement in photocatalytic activity over TiO2 under visible light irradiation. Almost complete photodecolorization of a 5 ppm Rh6G solution was achieved in 4 h, while only 64% of dye degradation was observed in TiO2 photoassisted process. This work provides a feasible route to fabricate high-performance immobilized ABO3-based nanomaterials, and the finding opens up a new venue for designing visible light sensitive ternary compounds for photocatalytical applications. A novel immobilized Ca0.6Ho0.4MnO3 photocatalyst has been developed with high photocatalytic activity for Rhodamine 6G (Rh6G) photodegradation under visible light irradiation. The nanocrystalline Ca0.6Ho0.4MnO3 films were successfully deposited by RF-magnetron sputtering on unheated quartz glass substrates using Ca0.6Ho0.4MnO3 powder as sputtering target and its photocatalytic functionalities have been explored. The visible-light-responsive photocatalytic activity of Ca0.6Ho0.4MnO3 films was evaluated by the photodegradation of Rh6G aqueous solutions under visible light irradiation. The reusability of Ca0.6Ho0.4MnO3 films on fresh dye samples was studied, showing an efficient reuse, without decreasing the photocatalytic decolorization efficiency. Furthermore, X-ray diffraction of the reused films did not reveal additional phases indicating high photochemical stability of the films even after reusing them in successive runs. The photocatalytic efficiency of the nanocrystalline Ca0.6Ho0.4MnO3 films was further compared with TiO2 films also produced by sputtering and the results revealed a significant improvement in photocatalytic activity over TiO2 under visible light irradiation. Almost complete photodecolorization of a 5 ppm Rh6G solution was achieved in 4 h, while only 64% of dye degradation was observed in TiO2 photoassisted process. This work provides a feasible route to fabricate high-performance immobilized ABO3-based nanomaterials, and the finding opens up a new venue for designing visible light sensitive ternary compounds for photocatalytical applications.

The complex [Ph4P]2[Cu(bdt)2] (1(red)) was synthesized by the reaction of [Ph4P]2[S2MoS2CuCl] with H2bdt (bdt = benzene-1,2-dithiolate) in basic medium. 1(red) is highly susceptible toward dioxygen, affording the one electron oxidized diamagnetic compound [Ph4P][Cu(bdt)2] (1(ox)). The interconversion between these two oxidation states can be switched by addition of O2 or base (Et4NOH = tetraethylammonium hydroxide), as demonstrated by cyclic voltammetry and UV-visible and EPR spectroscopies. Thiomolybdates, in free or complex forms with copper ions, play an important role in the stability of 1(red) during its synthesis, since in its absence, 1(ox) is isolated. Both 1(red) and 1(ox) were structurally characterized by X-ray crystallography. EPR experiments showed that 1(red) is a Cu(II)-sulfur complex and revealed strong covalency on the copper-sulfur bonds. DFT calculations confirmed the spin density delocalization over the four sulfur atoms (76%) and copper (24%) atom, suggesting that 1(red) has a "thiyl radical character". Time dependent DFT calculations identified such ligand to ligand charge transfer transitions. Accordingly, 1(red) is better described by the two isoelectronic structures [Cu(I)(bdt2, 4S(3-,)*)](2-) <--> [Cu(II)(bdt2, 4S(4-))](2-). On thermodynamic grounds, oxidation of 1(red) (doublet state) leads to 1(ox) singlet state, [Cu(III)(bdt2, 4S(4-))](1-).

Ca1-xSmxMnO3 (0≤x≤0.4) films were successfully fabricated on Indium Tin Oxide (ITO) coated quartz glass substrates by radio frequency magnetron sputtering technique (RF- magnetron sputtering) from compacted nanosized powder targets, and subsequent annealing at 800°C in air, for 6h. X-ray diffraction shows a pure typical perovskite phase for x≥0.1. Scanning electron microscopy and atomic force microscopy revealed that the film surface is dense, with low roughness, depending on the Sm content, even though a few cracks were observed. Crystallite size was found to decrease with the Sm content. The electrodes were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS).The oxide electrode's capacitance was estimated using both techniques and the corresponding roughness factors evaluated. The values obtained from the two methods show a good agreement. A comparison between the voltammetric data and those referred in the literature allowed finding out that the redox reaction occurring at the electrode surface involves the pair Mn4+/Mn3+. EIS measurements confirm the voltammetric data and they also give additional information about the film porosity and the charge transfer resistance. This last parameter is associated with the oxidation and reduction of the pair Mn3+/Mn4+and after normalized by the roughness factor shows an increase with samarium content.

Trace elemental content was analysed in edible tissues of Mytilus galloprovincialis collected in five different sampling areas near the mouth of river Tagus estuary in Lisbon. The concentrations of essential elements (S, K, Ca, Fe, Cu, Zn, As, Br and Sr) were determined by energy-dispersive X-ray fluorescence (EDXRF) spectrometry, while toxic elements (Cr, Cd, Hg, Se and Pb) were measured by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The results show that the essential elements K and S are present at the highest concentrations in all the studied samples reaching 2,920 and 4,520 μg g(-1) (fresh weight), respectively. The highest levels of heavy metals found were in two areas close to the city for Pb and Cd, but below the maximum allowed values.

We have measured the x-ray spectra from highly charged Si, S and Cl ions in collisions with thin foils using a high-resolution x-ray spectrometer. The observed lines have been assigned to various transitions in H-, He- and Li-like ions. For proper identification of line positions, the theoretical calculations have been carried out using a state-of-the-art MCDF code including QED effects, with which the experimental data is in excellent agreement. We have also observed, for the first time, x-rays arising out of the decay of long-lived resonant states in the He-like ions of each species. Details will be presented.

Os protocolos de replicação parcial de dados apresentam um grande potencial de escalabilidade. O SCORe é um protocolo para replicação parcial proposto recentemente que faz uso de controlo de concorrência multi-versão. Neste artigo abordamos um dos problemas principais que afeta o desempenho deste tipo de protocolos: a localidade dos dados, i.e., pode-se dar o caso do nó local não ter uma cópia dos dados a que pretende aceder, e nesse caso é necessário realizar uma ou mais operações de leitura remota. Assim, a não ser que se empreguem técnicas para melhorar a localidade no acesso aos dados, o número de operações de leitura remota aumenta com o tamanho do sistema, acabando por afetar o desempenho do mesmo. Nesse sentido, introduzimos um mecanismo de caching que permite replicar cópias de dados remotos de maneira a que seja possível servir localmente dados remotos enquanto que se mantém a consistência dos mesmos e a escalabilidade oferecida pelo protocolo. Avaliamos o mecanismo de caching com um benchmark conhecido da literatura e os resultados experimentais mostram resultados animadores com algum aumento no desempenho do sistema e uma redução considerável da quantidade de operações de leitura remota.

Systems externally reinforced by bonded fibre reinforced polymers (FRP) are widely used in the retrofitting and strengthening of reinforced concrete (RC) structures. A drawback of the usage of this technique lies on the uncertainty of the long term behaviour of those reinforcements. Researchers have paid heed to this aspect and a number of tests and alternative techniques have recently been described. An experimental programme developed to supplement work of the authors recently published and which focused on specimens not submitted to aggressive environments is described. The specimens used have the same geometry as in the previous paper, but they were exposed to salt fog cycles and dry/wet cycles with salt water for periods of 3000 h, 5000 h and 10,000 h. The interface of the glass fiber polymeric composite (GFRP)-to-concrete was characterized after the systems underwent such aggressive conditions. The GFRP wrap comprised of two layers and wet lay-up technique was used on its preparation and application. The cohesion and friction angle for GFRP-to-concrete interfaces were measured tat selected stages of ageing process and envelope failure laws were obtained based on the Mohr–Coulomb failure criterion. Changes of 27% in cohesion and 8% in the friction angle were found due to the attack of the interface and consequences of the changes are examined.

Currentcomputationalsystemsareheterogeneousbynature, featuring a combination of CPUs and GPUs. As the latter are becoming an established platform for high-performance computing, the focus is shifting towards the seamless programming of the heterogeneous systems as a whole. The distinct nature of the architectural and execution models in place raise several challenges, as the best hardware configuration is behavior and data-set dependent. In this paper, we focus the execution of compound computations in multi-CPU/multi-GPU environments, in the scope of Marrow algorithmic skeleton framework, the only, to the best of our knowledge, to support skeleton nesting in GPU computing. We address how these computations may be efficiently scheduled onto the target hardware, and how the system may adapt itself to changes in the CPU’s load and in the input data-set.

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Sandstone building stones are important in the building elements of Portuguese monuments, particularly in the western and southern regions. Alveolization due to salt crystallization was the most important degradation pattern found in the old sandstone façades of St. Leonardo’s Church, a Portuguese monument built in Atouguia da Baleia village in the Middle Age. Its sandstone façades have a widespread distribution of deep and large alveolization patterns mainly on portals and vaults that appeared as a result of the past and present vicinity of seashore. In this paper a summary of conservation interventions carried out in the past century in St. Leonardo’s Church is presented, as well as a summary of the studies carried out in the last decade. Then the degradation patterns on the sandstone walls of St. Leonard’s Church are shown and finally the evolution of the alveolization occurred on the sandstone walls over the last sixty to seventy years is analysed. Visual inspection of sandstone walls is compared with a survey performed by laser scanning, which seems to be a powerful technology to carry out 3D geometric modelling of the building elements of stone monuments and also the 3D mapping of stone degradation patterns.