The connection between the heat storage capability of PCM as a material property and their performance in real scale applications

Using phase change materials (PCM) for Thermal Energy Storage, the most important material property is their heat storage capability, usually given as h(T). Ideally, h(T) changes suddenly at a single temperature. However, many PCM change phase in a temperature range and show hysteresis. In addition, experience shows that even measurements with the same device on the same material can give different results when the heating rate, the amount of sample mass or the equipment device are varied. The question thus arises how to deal with different h(T) results when trying to predict the performance of a real scale application. This paper identifies the main origins of these effects and gives strategies for dealing with them.The research leading to these results has received funding from the European Commission Seventh Framework Programme (FP/2007-2013) under grant agreement n° PIRSES-GA-2013-610692 (INNOSTORAGE) and from the European Union’s Horizon 2020 research and innovation program under grant agreement No 657466 (INPATH-TES). The authors would like to thank the Catalan Government for the quality accreditation given to their research groups GREA (2014 SGR 123) and DIOPMA (2014 SGR 1543). GREA and DIOPMA are certified agents TECNIO in the category of technology developers from the Government of Catalonia. This work has been partially funded by the Spanish government (ENE2015-64117-C5-1-R (MINECO/FEDER)). Dr. Camila Barreneche and Dr. Aran Solé would like to thank Ministerio de Economía y Competitividad de España for Grant Juan de la Cierva, FJCI-2014-22886 and FJCI-2015-25741, respectively

Thermal effects on the resonance fluorescence of doubly dressed artificial atoms

In this work, robustness of controlled density of optical states in doubly driven artificial atoms is studied under phonon dissipation. By using both perturbative and polaron approaches, we investigate the influence of carrier-phonon interactions on the emission properties of a two-level solid-state emitter, simultaneously coupled to two intense distinguishable lasers. Phonon decoherence effects on the emission spectra are found modest up to neon boiling temperatures ($\sim 30$ K), as compared with photon generation at the Fourier transform limit obtained in absence of lattice vibrations (zero temperature). These results show that optical switching and photonic modulation by means of double dressing, do not require ultra low temperatures for implementation, thus boosting its potential technological applications.Comment: Submitted versio

Manuscript contexts and the transmission of the Agnus Castus herbal in MS Sloane 3160

MS Sloane 3160 is a miscellaneous volume containing one copy of the herbal Agnus Castus in Middle English. Traditionally, editions focused on texts in isolation and did not look in detail to the rest of the material, diminishing the potential of manuscript contexts in explaining how texts flow and are received by a specific audience. If we consider these groupings of texts a collective product in which all the co-texts are part of an internal dialogue, the importance of looking at the whole volume from a collective perspective becomes paramount in understanding the final aim of the compiler, and the processes of transmission of text and/or texts. The objective of this article has been to study the arrangement of the material contained in MS Sloane 3160 as a starting point to frame future comparison with manuscripts containing the same herbal. The results point to the identification of patterns which would confirm the “anthologistic impulse” (Lerer 2000). The structure of this manuscript would contain a spectrum of the most important areas that would cover the contents of a typical vademecum of the time, including religious texts, but more studies are needed in order to be able to assess these contexts in medical miscellanies. The impact and transmission of the Agnus Castus herbal needs to be studied collectively, and assessing the manuscript contexts in which the text is naturally embedded points to the right direction in understanding all the processes therein

Antecedents of academic performance of university students: academic engagement and psychological capital resources

Predicting academic performance is of key importance to the success, wellbeing and prosperity of students, their families, the economy, and the society at large. This study investigates the relationship between academic engagement, psychological capital (PsyCap) and academic performance. Data were collected in two different universities, one in Spain and another in Portugal. Students completed two self-report questionnaires regarding academic engagement and Psychological Capital. Academic performance was assessed through Grade Point Average, provided by the universities at the end of the exam period. The samples consisted of 389 and 243 undergraduate students, respectively. Results showed a positive relationship between academic engagement and PsyCap, on the one hand, and academic performance on the other, in both samples. Results also supported PsyCap as a full mediator in the relationship between academic engagement and academic performance. Exploration of alternative models yielded superior fit for the proposed model. Accordingly, academically engaged students were likely to experience higher levels of PsyCap, which in turn positively impacted their academic performance. The results point to the importance of considering psychological predictors, rather than the prevalent reliance on traditional predictors of academic performance

Financing Problems as a Pretext for a Change in the Spanish Social Security System Model: The Role of Financial Institutions and Their Media

This study summarizes the traditional characteristics of the Spanish Social Security System (generally taken from the European model), the different legal reforms that have come into force in recent years and the degree of penetration of important financial groups in the mass media which increased with the last financial crisis as well as the role developed by the insurance and financial entities benefiting from the change of model. The conclusion is that we are at the beginning of an interesting change in the Social Security model, aimed at the capitalization of social contributions by the private sector, which will obtain significant economic benefits in the management of old-age risk