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Abstract: Laminated glass is composed of two glass layers and a thin intermediate PVB layer, strongly influencing PVB''s viscoelastic behaviour its dynamic response. While natural frequencies are relatively easily identified even with simplified FE models, damping ratios are not identified with such an ease. In order to determine to what extent external factors influence damping identification, different tests have been carried out. The external factors considered, apart from temperature, are accelerometers, connection cables and the effect of the glass layers. To analyse the influence of the accelerometers and their connection cables a laser measuring device was employed considering three possibilities: sample without instrumentation, sample with the accelerometers fixed and sample completely instrumented. When the sample is completely instrumented, accelerometer readings are also analysed. To take into consideration the effect of the glass layers, tests were realised both for laminated glass and monolithic samples. This paper presents in depth data analysis of the different configurations and establishes criteria for data acquisition when testing laminated glass. [Copyright &y& Elsevier]

• Heracleum Persicum stems are used as biosorbent for the removal of paraquat and diquat. • This biosorbent is cheap, eco-friendly and displays excellent removal efficiency. • Suited conditions for adsorbing herbicides found by a multivariate optimization. • Biosorbent is reused 5 times with removal efficiencies for both herbicides above 82%. • High ionic strength of the medium reduces the sorption capability after biosorbent aggregation. The use of natural materials as biosorbents or substrates for the removal of pollutants from environmental waters is an interesting approach in line with the Green Chemistry principles. This strategy minimizes environmental pollution, and it provides natural material residues with a new use before its final disposal. Heracleum Persicum stems are proposed in this article as precursor of a lignocellulosic biosorbents capable of retaining two herbicides, paraquat (PQ) and diquat (DQ), from environmental waters. Both pollutants are cationic, and thus they can interact with the negatively charged functional groups found in the lignocellulosic biosorbents. Their preparation is straightforward, and the ensuing micrometric biosorbents were morphological and superficial characterized by microscopy, infrared spectroscopy, and Zeta potential analysis. Adsorption and desorption studies were investigated in detail. Kinetics data fitted to the pseudo-second-order kinetic model supporting the diffusion mechanism. Under the optimal conditions, adsorption/desorption were carried out at least 5 cycles and the removal efficiencies for PQ and DQ were of 82.2 and 93.2%, respectively. [ABSTRACT FROM AUTHOR]

• A composite is synthesized using recycled polystyrene and cotton. • The composite is prepared by simple dip coating minimizing reagents and steps. • The material allows the removal of oil from water. • The composite can be applied for the removal of PAHs from water. The massive production of plastics and their chemical stability make these materials primary toxicological and environmental threats. Therefore, the main aim of this research is to prepare a composite material using a recycled polymer (polystyrene obtained from food packages) as adsorbent and natural fibers (cotton) as substrate. The research has a threefold environmental approach: (i) it allows the recycling of plastics residues; (ii) it proposes an almost solventless recycling procedure which does not require sophisticated and expensive devices; and (iii) the resulting adsorbent can be used for environmental remediation. The composite, which has been characterized by infrared spectroscopy (IR) and scanning electron microscopy (SEM), has been initially evaluated for the direct oil/water separation. The results open the door to the use of the composite as a physical barrier in case of oil spills. After its successful preliminary evaluation, it has been applied to the removal of polycyclic aromatic hydrocarbons (PAHs) from water. The main variables affecting the extraction of PAHs with the composite were studied and working under the best conditions, the absolute recoveries vary in the range from 54.7% (fluorene) to 74% (pyrene). These values are acceptable as they have been evaluated at a relatively high concentration level (50 μg/L). Also, if the results are contextualized considering the analytical procedure followed for their calculation, the accumulated recoveries vary from 65 (fluorene) to 93% (pyrene). [ABSTRACT FROM AUTHOR]

A large active extensional fault is characterized, which will contribute to improve seismic hazard assessment in an intraplate region of the Mediterranean domain whose seismic potential until today has been underestimated. The Cucalón-Pancrudo fault (CPF) is a NNW-SSE striking extensional fault that represents the negative (extensional) inversion of a previous, Late Variscan and Paleogene, transpressional fault. It is part of the Río Grío-Pancrudo fault zone, the largest active structure in the intraplate central-eastern Iberian Chain. This study focuses on characterizing the CPF structure, morphotectonics and paleoseismology. The fault offsets a well-known regional planation surface (lower level of the Fundamental Erosion Surface, FES3, 3.5 Ma), providing a basis for calculating the maximum fault throw (c. 280–300 m, including the contribution of a minor synthetic fault and a gentle accommodation monocline), and hence estimating the net slip (c. 305–325 m) and the long-term slip rate (0.09 mm/a). A trench dug in a Holocene fluvial terrace reveals an ensemble of listric, domino-style ruptures synthetic to the main fault. They were activated during at least two paleoseismic events (X, Z), 14.9 ± 1.4 ka and 6.9 ± 0.4 ka in age. An intermediate event (Y), dated to 11.0 ± 1.0 ka, as an uncertainty because the attribution of their ruptures to event Z cannot be ruled out. The total net slip accumulated during these events (1.15–1.25 m) provides an apparent short-term slip rate of 0.07–0.09 mm/a, very similar to the long-term slip rate. Nevertheless, it is very likely that the faults exposed in the surveyed trench do not represent a complete paleoseismic record. Therefore, the actual slip rate during Late Pleistocene-Holocene times could be significantly higher, approaching that reported for most of the recent extensional faults in the central Iberian Chain. The inclusion of CPF in the map of Active Faults of Iberia (QAFI database) will result in improving seismic hazard assessment in Spain. • The largest active fault zone within the central-eastern Iberian Chain, Spain. • Extensional fault inherited from a contractive, Paleogene fault. • Calculation of fault throw and its distribution from geomorphological markers. • Two-three paleoearthquakes identified, the youngest one in Holocene time. [ABSTRACT FROM AUTHOR]

Abstract: The use of WiMAX cellular networks has arisen as a promising solution in order to provide broadband access over large, often shadowed, areas. As in other cellular networks, localization of users is extremely useful for many services and even essential for some civilian and/or military logistic operations. In a cellular WiMAX network, a node can obtain its position from beacons received by several cell base stations. Therefore, securing the localization method against potential false or erroneous feedback is of paramount importance in order to allow the nodes to get reliable position estimations. This fact implies not only making the localization method robust against erroneous or forged measurements, but also identifying which WiMAX base stations are providing such measurements. In this paper, we propose a robust localization method that can identify up to k malicious or misbehaving base stations and provide with an accurate estimation of the node position even in their presence. Simulation results prove that this proposal outperforms other existing detection techniques. [Copyright &y& Elsevier]