This work presents experimental values for the excess volumes (V m E ) at 291.15, 298.15, 318.15, and 328.15 K; excess enthalpies (H m E ) at 291.15, 298.15, and 318.15 K; at 101.32 kPa for mixtures of ethyl ethanoate with each of six alkanes (from pentane to decane). The results for the six mixtures show that the thermal coefficient (∂V m E /∂T) p is positive and that (∂H m E /∂T) p presents changes in the sign. The Fredenslund method was applied to establish the thermodynamic consistency of the VLE data. Of the six systems considered here, only two, ethyl ethanoate + hexane and ethyl ethanoate + heptane, form minimum-boiling azeotropes, with coordinates (x az , T az /K) of (0.339, 338.15) and (0.834, 349.99), respectively. Simultaneous correlations carried out with the VLE and H m E data using a polynomic model with temperature-dependent coefficients were found to be acceptable. Application of two different versions of the UNIFAC model for the VLE data, one by Hansen et al. (Ind. Eng. Chem. Res. 1991, 30, 2355 and the other by Gmehling et al. (Ind. Eng. Chem. Res. 1993, 32, 178), gave similar estimations for the six systems, which we consider to be acceptable. The second method gave good predictions of H m E .

a b s t r a c tThis work makes a theoretical-experimental contribution to the study of ester and alkane solutions. Experimental data of isobaric vapor-liquid equilibria (VLE) are presented at 101.3 kPa for binary systems of methyl ethanoate with six alkanes (from C 5 to C 10 ), and of volumes and mixing enthalpies, v E and h E . An interpretation of the behavior and a verification of structural models proposed previously by the same group are also given. For the treatment of thermodynamic data a polynomial model is proposed to obtain a simultaneous correlation of different properties available for a same system. Liquid-liquid equilibrium (LLE) data at low pressure are also used and c E p values, taken from literature, to perform the correlations described, generating a working procedure which is started on LLE data. The properties used for correlating are obtained in very different working conditions making it difficult to obtain a single correlation. However, the procedure followed produces good multiproperty correlations for each of the systems. An extended version of the NRTL model is also used with the purpose of comparing the efficacy of the method and model proposed, and produces acceptable results for the isobaric and isothermal VLE equilibrium but not for the LLE. Specifically, the model does not take into account the variation in h E = ϕ(T), as it does not reproduce the c E p . Estimates of the same properties made with the UNIFAC group contribution method are comparable to those obtained with the correlative NRTL method.

A thermodynamic study is carried out on binary systems composed of propyl ethanoate with six alkanes, from pentane to decane. Vapor pressures of the ester and the isobaric vapor−liquid equilibria of these six mixtures were measured at 101.32 kPa in a small-capacity ebulliometer and also the mixing properties,h E over a range of temperatures and at atmospheric pressure. Adequate correlations are drawn for the surfaces y E = y E (x,T) with an interpretation on the behavior of the mixtures and also using c p E data from literature. The mixing processes are all endothermic with a change in the slope direction of the function h E = h

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Analysis of water level and current meter series from different locations on the island shelf of Gran Canaria reveals strong variations in tidal properties. Semidiurnal sea level amplitudes agree with the results obtained from global tidal models for this region only on the northern coast of the island, while they decrease towards the southwest (10 cm difference for the M2 constituent). Semidiurnal currents present maxima at the southeastern and northwestern extremities of the island (30-40 cm s-' for MJ and minima in the north-northeast and southwest (3-6 cm s-' for M,), showing simultaneous strong changes in the phase. Diurnal levels and currents display smaller variations than the semidiurnal band. The behaviour of semidiumal constituents is studied with the help of analytical and numerical solutions, in which the incident wave is modelled by a barotropic M2 Kelvin wave. The results show that the insular shelf could be a source of differences in level amplitudes around the island and could be also responsible for the enhancement of currents in the southeast and northwest. They also show that the variation of the current phases is due to the amplification of the standing character of the wave at the northeastern and southwestern parts of the shelf. 0 Elsevier, Paris / Ifremer / Cnrs / Ird tide / tidal current / island / numerical modelling / Canary Islands R&urn6-Variation des propriCtCs de la mar& dans les eaux de la Grande Canarie. L'analyse de series chronologiques du niveau de la mer et de la courantometrie, en plusieurs points du plateau continental de la Grande Canarie, revele de grandes variations dans les proprietes de la maree. Les amplitudes des variations semi-diumes du niveau de la mer sont en accord avec le modble global de maree au nord de l'ile, mais elles diminuent au sud-ouest (de 10 cm pour la composante MJ. Le courant semi-diume presente un maximum au sud-est et au nord-ouest de l'ile (de 30 a 40 cm s-l pour M,) et un minimum au nord-nord-est et au sud-ouest (de 3 a 6 cm s-' pour M,) avec, simultanement, une forte variation de phase. Les variations de periode diume des niveaux et des courants sont plus faibles que celles de periode semi-diurne. Les composantes semi-diumes sont Ctudiees par des methodes analytiques et numeriques, en considerant que I'onde incidente est une onde barotrope de Kelvin. Les resultats indiquent que le plateau continental est probablement a l'origine des differences observees dans les variations du niveau de la mer autour de l'ile et dans le renforcement des courants au sud-est et au nord-ouest. 11s montrent Cgalement que la variation de phase du courant est due a l'amplification du caractere stationnaire de l'onde sur le plateau continental, au nord-est et au sud-ouest de l'ile.

INTRODUCCIÓN. El plagio se está convirtiendo en un tema de creciente interés en el ámbito universitario; sin embargo, apenas existen estudios que se centren en este tema desde la percepción del alumnado con respecto a políticas institucionales y de aula. Este trabajo pretende analizar la percepción del alumnado de las facultades de Ciencias de la Educación del Sistema Universitario de Galicia acerca del plagio en relación a la existencia de una normativa ética reguladora y de la actuación del profesorado en las aulas. MÉTODO. Se efectuó un estudio cuantitativo, de corte transversal, descriptivo, correlacional e inferencial. Se empleó una muestra de 2.331 estudiantes universitarios a la cual se aplica un cuestionario de atribuciones para la detección de coincidencias en trabajos académicos (Rebollo-Quintela, Espiñeira-Bellón y Muñoz-Cantero, 2017). RESULTADOS. Los datos muestran que el alumnado ofrece valoraciones generalmente negativas de las causas que pueden motivarle a cometer plagio, en contraposición con valoraciones ligeramente más elevadas sobre las actuaciones del profesorado en las aulas. Se evidencia la presencia de correlaciones estadísticamente significativas entre varios ítems, así como una tendencia a valorar en términos más negativos las causas y actuaciones del profesorado conforme aumentan de curso; es decir, a valorar más la información del docente sobre plagio que la normativa existente, a nivel informativo y sancionador, en los primeros cursos y viceversa. DISCUSIÓN. Se discuten los resultados teniendo en consideración estudios precedentes, así como en relación a la existencia de la normativa en las tres universidades gallegas, estableciendo conclusiones que redunden en la mejora de las medidas a considerar y aplicar para evitar el plagio en las aulas universitarias.