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• A White-Etching layer was found in the field near the squat-type defects. • Several root-causes were identified as responsible for the formation of studs. • Introduction of new vehicles is the most important cause. Squat-type defects are becoming an increasing issue in rail transportation systems. In this work, a root-cause analysis was carried out to identify the main causes leading to squat formation in a metropolitan railway. Several inspection visits were carried out after the first squat appeared in December 2017 in order to collect evidence from the field. The Corrugation-Analysis Trolley (CAT) was used to perform spectral analysis and a number of rail sections were extracted from critical locations of the railway for laboratory analysis of the microstructure. Four root-causes for squat formation were identified, namely: rail corrugation derived from resonance frequencies induced by vehicle-track dynamic interaction, increase of traffic, problems related to maintenance management and inadequate rail grinding. The analysis of data from the field revealed a clear correlation between the formation of squat-type defects and the presence of a White Etching Layer (WEL) on the surface of the rail, whose formation was shown to be most likely induced during the rail grinding operations as it was verified after a controlled grinding experiment. The increase of traffic over the last 15 years, as well as rail corrugation, which was linked with the introduction of new vehicles to the system, were also considered key factors for squat formation. [ABSTRACT FROM AUTHOR]

Synthesis and processing methods can have a significant influence on the physical properties of spinel zinc ferrite since it can produce microstructures characterized by different microstructural parameter such as the arrangement of the ions, lattice parameter, crystallite size and lattice strains (or microstrain). In this work, it has been evaluated the magnetic properties of samples prepared by ceramic synthesis, sol-gel and a third one provided by a ceramic powder supplier. Later, the synthesized samples have been ball-milled for 50 h and compared with a sample prepared by mechanochemical synthesis during 150 h. X-ray powder diffraction (XRD) analysis, performed in order to understand the relation between microstructure and magnetic properties, showed that these four materials are characterized by different values of the microstructural parameters (lattice constant, inversion degree and crystallite size). It was concluded that cation inversion is the most important parameters that can be effective in the deviation of the magnetic properties of zinc ferrite from the properties of the bulk form. Finally, the magnetization curves for the samples milled for 50 h were very similar to the sample prepared by mechanochemical, as expected from the similar microstructural parameters obtained from their XRD patterns. The inversion degree for these samples varied from 0.56 to 0.61 with saturation magnetization at 5 K around 79.0 emu/g. Although structural and chemical properties of this material can be selected by a proper choice of the preparation method, it is also possible to obtain the same microestructural and magnetic properties by a thermomechanic process, regardless of the synthesis method used. • The magnetic properties of zinc ferrite depend on the synthesis method. • Ceramic synthesis, sol-gel, mechanochemical synthesis and a provided sample are compared. • The magnetic properties strongly depend on the microstructure parameters like inversion degree and particle size. • After long time milling, all the samples show the same magnetic and structural properties. [ABSTRACT FROM AUTHOR]

Wild fish belonging to four species belonging to different trophic groups were captured at three distances from fish farm facilities: long distance (>5 Km), medium distance (1.5 Km) and close to sea-cages. Flesh, brain, liver and gonads were sampled for fatty acid analysis. Fish aggregated near sea-cages showed accumulation of fatty acids of vegetable origin in the studied tissues, due to surplus feed consumption or via predation of fish that consumed the feed. Gonads accumulated vegetable fatty acids in different manner in the different species, and the species least and most influenced by fish-feeds were selected for gonad histological examination. Results showed an acceleration of the final stages of the oocyte development in fish aggregated near fish farms compared to fish captured at long distance. Differences in oocyte development were more acute in the species which incorporated higher quantities of vegetable fatty acids. Image 1 • Sea-cage aggregated wild fish consume lost pellets rich in terrestrial fatty acids. • Fatty acid profiles of four fish of different trophic level were analysed. • Flesh, brain, liver and gonad fatty acids reflect the composition of surplus feed. • Gonad development is accelerated in fish species aggregated at farms. • Consumption of lost pellets modulates fatty acid composition and gonad maturation. [ABSTRACT FROM AUTHOR]

This paper presents a novel cooling and desalination system that uses seawater as coolant, and that has a high energetic and internal mass integration, as well as higher capacity and efficiency levels. The proposed system was simulated using Aspen Plus software; its operative behavior was also evaluated in order to prove its technical feasibility. Using a 23 kW simple-effect absorption cooling machine as a basis, and utilizing the produce of desalination as coolant, this technological approach increases the system's capacity by a factor of 87.4, to 2012 kW. It also increases the COP value to 6.15, 8.54 times greater than the 0.72 COP reported for this type of systems. Furthermore, the system produces 73,569 L/day of water, with an RR of 0.56 and a PR of 6.63. The proposed technology presents a setup that allows for a high energetic and internal mass integration, which increases the system's capacity and efficiency. • Absorption cooling and desalination system with a novel internal energetic and mass integration • Based on a 23 kW simple-effect absorption cooling machine, the proposed technology increases 8.54 times the efficiency. • Proposed technology, with the internal energy and mass integration, increases 87.4 times the cooling capacity. • The water production is 73,569 L/day, with a RR of 0.56 and a PR of 6.63. [ABSTRACT FROM AUTHOR]