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In 1968, Israel Gohberg and Naum Krupnik discovered that local spectra of singular integral operators with piecewise continuous coefficients on Lebesgue spaces \(L^p(\Gamma)\) over Lyapunov curves have the shape of circular arcs. About 25 years later, Albrecht Böttcher and Yuri Karlovich realized that these circular arcs metamorphose to so-called logarithmic leaves with a median separating point when Lyapunov curves metamorphose to arbitrary Carleson curves. We show that this result remains valid in a more general setting of variable Lebesgue spaces \(L^{p(\cdot)}(\Gamma)\) where \(p:\Gamma\to(1,\infty)\) satisfies the Dini-Lipschitz condition. One of the main ingredients of the proof is a new condition for the boundedness of the Cauchy singular integral operator on variable Lebesgue spaces with weights related to oscillations of Carleson curves.

Macromolecular X-ray crystallography is an important and powerful technique in drug discovery, used by pharmaceutical companies in the discovery process of new medicines. The detailed analysis of crystal structures of protein-ligand complexes allows the study of the specific interactions of a particular drug with its protein target at the atomic level. It is used to design and improve drugs. The starting point of these studies is the preparation of suitable crystals of complexes with potential ligands, which can be achieved by using different strategies described in this chapter. In addition, an introduction to X-ray crystallography is given, highlighting the fundamental steps necessary to determine the three-dimensional structure of protein-ligand complexes, as well as some of the tools and criteria to validate crystal structures available in databases.

The physical, chemical and mineralogical characterisation of the ash resulting from a pulp mill boiler was performed in order to investigate the valorisation of this waste material through the production of added-value glassy materials. The ash had a particle size distribution in the range 0.06-53μm, and a high amount of SiO2 (∼82wt%), which was present as quartz. To favour the vitrification of the ash and to obtain a melt with an adequate viscosity to cast into a mould, different amounts of Na2O were added to act as fluxing agent. A batch with 80wt% waste load melted at 1350°C resulting in a homogeneous transparent green-coloured glass with good workability. The characterisation of the produced glass by differential thermal analysis and dilatometry showed that this glass presents a stable thermal behaviour. Standard leaching tests revealed that the concentration of heavy metals in the leaching solution was lower than those allowed by the Normative. As a conclusion, by vitrification of batch compositions with adequate waste load and additive content it is possible to produce an ash-based glass that may be used in similar applications as a conventional silicate glass inclusively as a building ecomaterial. © 2010 Elsevier B.V.

A collection of 155 accessions of ancient Portuguese common beans (Phaseolus vulgaris L) was evaluated in relation to the content of 8 minerals (Zn, Cu, Fe, Mn, Ca, Mg, P and K) important for human nutrition. A high degree of variability for P. Fe, Zn, Cu, Mn and Ca was observed in the collection. Total correlation matrix analysis revealed the existence of two important sets of strong positive correlations (P <= 0.0001), one involving P, Fe, Zn, Cu and protein, and the other Ca and Mn. The principal component analysis showed that Zn, Fe and Cu are highly correlated to the first component (27% of variability) and Mn and Ca to the second component (22% of the variability). The high mineral variability observed in the seeds of this common bean collection could be useful for the selection of cultivars with higher nutrition value and for the improvement of seed nutrition quality traits. (C) 2010 Elsevier Inc. All rights reserved.

For the characterization of the new materials and for a better understanding of the connection between structure and properties it is necessary to use more and more sensible methods to study molecular movement at nanometric scale. This paper presents the experimental basis for a new electrical method to study the fine molecular movements at nanometric scale in dielectric materials. The method will be applied for polar and non-polar materials characterization. Traditionally, the electrical methods used to study the molecular movements are based on the movements of the dipoles that are parts of the molecules. We have proposed recently a combined protocol to analyze charge injection/extraction, transport, trapping and detrapping in low mobility materials. The experimental results demonstrate that the method can be used to obtain a complex thermogram which contains information about all molecular movements, even at nanoscopic level. Actually during the charging process we are decorating the structure with space charge and during the subsequent heating we are observing an apparent peak and the genuine peaks that are related to charge de-trapping determined by the molecular movement. The method is very sensitive, very selective and allows to determinate the parameters for local and collective molecular movements, including the temperature dependence of the activation energy and the relaxation time.

The isothermal charging current and the isothermal discharging current in low mobility materials are analyzed either in terms of polarization mechanisms or in terms of charge injection/extraction at the metal-dielectric interface and the conduction current through the dielectric material. We propose to measure the open-circuit isothermal charging and discharging currents just to overpass the difficulties related to the analysis of the conduction mechanisms in dielectric materials. We demonstrate that besides a polarization current there is a current related to charge injection or extraction at the metal-dielectric interface and a reverse current related to the charge trapped into the shallow superficial or near superficial states of the dielectric and which can move at the interface in the opposite way that occurring during injection. Two important parameters can be determined (i) the highest value of the relaxation time for the polarization mechanisms which are involved into the transient current and (ii) the height of the potential barrier W-0 at the metal-dielectric interface. The experimental data demonstrate that there is no threshold field for electron injection/extraction at a metal-dielectric interface.

The inductive fault current limiter is less compact and harder to scale to high voltage networks than the resistive one. Nevertheless, its simple construction and mechanical robustness make it attractive in low voltage grids. Thus, it might be an enabling technology for the advent of microgrids, low voltage networks with dispersed generation, controllable loads and energy storage. A new methodology for reverse engineering of inductive fault current limiters based on the independent analysis of iron cores and HTS cylinders is presented in this paper. Their electromagnetic characteristics are used to predict the devices' hysteresis loops and consequently their dynamic behavior. Previous models based on the separate analysis of the limiters' components were already derived, e.g. in transformer like equivalent models. Nevertheless, the assumptions usually made may limit these models' application, as shown in the paper. The proposed methodology obviates these limitations. Results are validated through simulations.