2 resultados para Feast and famine regime

em Universidade Complutense de Madrid


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In this paper we analyze the structure of Fe-Ga layers with a Ga content of ∼30 at.% deposited by the sputtering technique under two different regimes. We also studied the correlation between the structure and magnetic behavior of the samples. Keeping the Ar pressure fixed, we modified the flow regime from ballistic to diffusive by increasing the distance between the target and the substrate. X-ray diffraction measurements have shown a lower structural quality when growing in the diffusive flow. We investigated the impact of the growth regime by means of x-ray absorption fine structure (XAFS) measurements and obtained signs of its influence on the local atomic order. Full multiple scattering and finite difference calculations based on XAFS measurements point to a more relevant presence of a disordered A2 phase and of orthorhombic Ga clusters on the Fe-Ga alloy deposited under a diffusive regime; however, in the ballistic sample, a higher presence of D0_3/B2 phases is evidenced. Structural characteristics, from local to long range, seem to determine the magnetic behavior of the layers. Whereas a clear in-plane magnetic anisotropy is observed in the film deposited under ballistic flow, the diffusive sample is magnetically isotropic. Therefore, our experimental results provide evidence of a correlation between flow regime and structural properties and its impact on the magnetic behavior of a rather unexplored compositional region of Fe-Ga compounds.

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The rise of neoliberalism and the experience of several economic crises throughout 1960’s and 70’s have opened the way to question the ability of welfare state to satisfy the basic needs of the societies. Therefore the term “welfare state” left its place to “welfare regime” in which the responsibilities for the well being of the societies are distributed among state, market and families. Following the introduction of this new term, several typologies of welfare regimes are started to be discussed. Esping-Andersen’s (1990) regime typology is considered to be one of the most significant one which covers most of the European countries. On the other hand, it has also led to criticisms for being lack of several aspects. One of them was done by Ferrera (1996), Moreno (2001), Boboli (1997) and Liebfreid (1992), which discusses that the grouping of Mediterranean countries of Europe -Greece, Italy, Spain and Portugal- within the conservative regime type. Those authors affirm that Southern European countries have their peculiar features in terms of structure of welfare provision and they form a fourth type which may be called "Mediterranean/ Southern European Regime". At this point, this doctoral thesis carries the discussion one step further and covers a profound research to answer some fundamental questions. Chiefly, clarifying whether it is possible to talk about a coherent grouping between the Mediterranean countries of Southern Europe in terms of their welfare regimes is our first objective. Then by assuming that it has an affirmative response, it is aimed to reflect the characteristics of this grouping. On the other hand, those group features are not static in time and they are sensible to various economic changes...