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We have developed a new method to measure the viscosity of micrometric films by thermomechanical analysis with a hemispherical probe of millimetric diameter. The loading curve (displacement vs. time) recorded as the probe tip crosses the whole film at constant load until it touches the substrate is fitted to a theoretical curve shape that has been obtained after solving the problem of liquid flow under the probe tip. The method has been validated by measuring the viscosity of rosin films. It has been applied to analyze the thermal evolution of unstable liquid films that appear on Ba propionate, Ce(III) propionate and a low-fluorine precursor film of YBa2Cu3O6+x. During pyrolysis of the last two films, viscosity first diminishes due to heating and then it increases as solid oxide particles are formed inside the liquid.

The ability to detect human fecal pollution in water is of great importance when assessing the associated health risks. Many microbial source tracking (MST) markers have been proposed to determine the origin of fecal pollution, but their application remains challenging. A range of factors, not yet sufficiently analyzed, may affect MST markers in the environment, such as dilution and inactivation processes. In this work, a statistical framework based on Monte Carlo simulations and non-linear regression was used to develop a classification procedure for use in MST studies. The predictive model tested uses only two parameters: somatic coliphages (SOMCPH), as an index of general fecal pollution, and human host-specific bacteriophages that infect Bacteroides thetaiotaomicron strain GA17 (GA17PH). Taking into account bacteriophage dilution and differential inactivation, the threshold concentration of SOMCPH was calculated to be around 500 PFU/100 mL for a limit of detection of 10 PFU/100 mL. However, this threshold can be lowered by increasing the analyzed volume sample, which in turn lowers the limit of detection. The resulting model is sufficiently accurate for application in practical cases involving MST and could be easily used with markers other than those tested here.

The threats posed by floating marine macro-litter (FMML) of anthropogenic origin to the marine fauna, and marine ecosystems in general, are universally recognized. Dedicated monitoring programmes and mitigation measures are in place to address this issue worldwide, with the increasing support of new technologies and the automation of analytical processes. In the current study, we developed algorithms capable of detecting and quantifying FMML in aerial images, and a web-oriented application that allows users to identify FMML within images of the sea surface. The proposed algorithm is based on a deep learning approach that uses convolutional neural networks (CNNs) capable of learning from unstructured or unlabelled data. The CNN-based deep learning model was trained and tested using 3723 aerial images (50% containing FMML, 50% without FMML) taken by drones and aircraft over the waters of the NW Mediterranean Sea. The accuracies of image classification (performed using all the images for training and testing the model) and cross-validation (performed using 90% of images for training and 10% for testing) were 0.85 and 0.81, respectively. The Shiny package of R was then used to develop a user-friendly application to identify and quantify FMML within the aerial images. The implementation of this, and similar algorithms, allows streamlining substantially the detection and quantification of FMML, providing support to the monitoring and assessment of this environmental threat. However, the automated monitoring of FMML in the open sea still represents a technological challenge, and further research is needed to improve the accuracy of current algorithms.

When gases evolve during a chemical reaction, a fraction of the reaction heat is lost with them. We have analyzed, both theoretically and experimentally, the deviations that this effect can produce on the determination of the reaction heat by differential scanning calorimetry (DSC). It is shown that, even in the absence of gas overheating, deviations related to variations in the sample heat capacity can be substantial in experiments involving very intense DSC peaks. However, experiments performed on thermal decomposition of metal organic salts and on evaporation of liquids have shown that deviations usually arise from gas overheating This work was partially funded by the Spanish Programa Nacional de Materiales through projects MAT2011-28874-C02-02 and by the Generalitat de Catalunya contract No. 2009SGR185

We have developed a new method to measure the thermal conductivity of powders by differential scanning calorimetry (DSC) that works with masses in amounts as low as tens of mg. The method is based on that used by Camirand to determine the thermal conductivity of materials in the form of thin sheets but introducing a hemispherical pan to contain powders in such a way that the issue of heat transfer is reduced to a one-dimensional problem. The modification of the method was successfully validated on obtaining identical results in determining the thermal conductivity of a commercial silicone with both Camirand"s method and the modified method. We have also tested our method with materials that, in bulk, cover a wide range of thermal conductivities and have performed the experiments with several atmospheres and reference metals. The results are consistent with already published general trends in that they confirm that thermal conductivity of powders is mainly governed by thermal conduction through the surrounding gas This work was partially funded by the Spanish Programa Nacional de Materiales through projects MAT2011-28874-C02-02 and by the Generalitat de Catalunya contract No. 2009SGR-185

A new method is developed to obtain the kinetic parameters of polymer crystallization from measure- ments of the transformation rate usually done at (but not restricted to) constant heating or cooling rates. It can be considered a generalization of the Fiedman's isoconversional method to deal with the Hoffman- Lauritzen temperature dependence. Apart from delivering the U* and Kg parameters as a function of the transformed fraction, this method allows to predict the crystallization course for an arbitrary thermal history. It has been applied to the crystallization of PET and PA6 samples, monitored by differential scanning calorimetry (DSC). This work was funded by the Spanish Programa Nacional de Materiales through project MAT2014-51778-C2-2-R. We also acknowledge financial support from the Generalitat de Catalunya (contract num.SGR948) and from the University of Girona (program MPCUdG2016)

Recrystallization of Cu deformed under compression has been monitored by differential scanning calorimetry (DSC) with experiments carried out at constant heating rate. From these experiments, an isothermal crystallization process has been predicted by the classical Kolmogorov-Johnson-Mehl-Avrami (KJMA) kinetics and by model-free isoconversional analysis. Whereas prediction by KJMA does not match the experimental curve, the isoconversional prediction is successful. The paper also highlights the need to correct the raw DSC curves to obtain the actual sample temperature and to avoid curve distortion due to thermal inertia This work was partially funded by the Spanish Programa Nacional de Materiales through projects MAT2014-51778-C2-2-R

The chapter focuses on students’ arguments with a framework based on the Theory of Argumentation of Argumentation of Perelman and Olbrechts-Tyteca (1958). From this perspective, which joints dialectics and rhetoric, argumentation is understood as the set of discursive techniques that will convince the audience of the validity of the theses presented. The general aim is to find a new way to interpret students’ misconceptions and reasoning, with particular reference to the role of premises and argumentative schemes they use, which we consider part of common sense. The chapter is based on two studies. The first study was carried out with teacher trainees’ students in the university. Written answers to three qualitative kinematics problems were compiled. In the second study, held in a secondary school class, small group discussions answering a question about free fall were video recorded. The results provide new insights into students’ scientific misconceptions and into the reworking of knowledge that emerges in the students’ discussions in small groups. The implication for science education is that focusing explicitly on argumentation in science classes and using the same kind of arguments students use, and discussing them, is likely to improve not only students’ argumentative skills, but also their conceptual understanding of science itself

Sumario: 1. INTRODUCCION. 2. EL REGIMEN JURIDICO DEL SUBSUELO URBANO, a) Analisis conceptual, b) Analisis doctrinal, c) Principales notas caracteristicas del subsuelo urbano, d) La segregacion del subsuelo publico, su desafectacion y privatizacion, e) Configuracion juridica del subsuelo en la legislacion sectorial. 3. LA ORDENACION URBANISTICA DEL SUBSUELO, a) Ambito competencial. b) La intervencion urbanistica sobre el subsuelo, c) La Ley 22/1998, de 30 de diciembre, que aprueba la Carta Municipal de Barcelona. 4. ANALISIS DE SUPUESTOS SOBRE ORDENACION DEL SUBSUELO URBANO DEMAMAL. a) Algunas experiencias representativas a nivel internacional, b) El Plan especial de galerias de servicios del Ayuntamiento de Barcelona, c) El Plan especial de redes de telecomunicaciones por cable, del Ayuntamiento de Barcelona. 5. LOS APARCAMIENTOS SUBTERRANEOS EN EL DOMINIO PUBLICO. EL APROVECHAMIENTO COMUNAL DEL SUBSUELO, a) Los aparcamientos subterraneos en el demanio publico, b) El aprovechamiento comunal del subsuelo. 6. CONSIDERACIONES FINALES. 7. BIBLIOGRAFIA CONSULTADA Y REFERENCIADA.