An unconstrained 3-D micromagnetic model for magnetite grains with resolutions up to 23 x 23 x 63 is presented. The model has been used to investigate the magnetic domain states of submicron parallelepipeds with various elongations. The method of fast Fourier transformation (FFT) has been implemented in three dimensions to accelerate the computation of the magnetostatic energy and its gradient, assuming constant magnetization for each subcube of the model. A 3-D implementation of the exchange energy and its gradient, using a five-point formula to approximate the Laplace operator, was chosen. Special attention has been paid to single-domain (SD) or flower states and pseudo-single-domain (PSD) configurations. A circular configuration, called vortex state, has been found to have the lowest energy of various PSD states. As a local energy minimum (LEM), the free energy of the vortex state is compared to that of a single-domain state. A comparison of these energies is used to determine a lower and an upper threshold size for the SD to PSD transition. In the interval between these two threshold sizes both configurations, SD and PSD, coexist. Above the upper threshold size we found metastable double-vortex configurations which seem to represent three-domain structures with closure domains.

This article focuses on systematically highlighting the ways to optimize waste-to-energy plants in terms of their energy efficiency as an indicator of the positive effect with regard to climate control. Potentials for increasing energy efficiency are identified and grouped into categories. The measures mentioned are illustrated by real-world examples. As an example, district cooling as a means for increasing energy efficiency in the district heating network of Vienna is described. Furthermore a scenario analysis shows the relevance of energy efficiency in waste management scenarios based on thermal treatment of waste with regard to climate control. The description is based on a model that comprises all relevant processes from the collection and transportation up to the thermal treatment of waste. The model has been applied for household-like commercial waste. The alternatives compared are a combined heat and power incinerator, which is being introduced in many places as an industrial utility boiler or in metropolitan areas where there is a demand for district heating and a classical municipal solid waste incinerator producing solely electrical power. For comparative purposes a direct landfilling scenario has been included in the scenario analysis. It is shown that the energy efficiency of thermal treatment facilities is crucial to the quantity of greenhouse gases emitted.

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Mit einem Leben in Muße ist das Versprechen eines selbstbestimmten und erfüllten Daseins verbunden. Dabei ist keineswegs klar, was Muße ausmacht. Durch die Unterscheidung von Arbeit und Freizeit allein ist das Spezi kum der Muße nicht zu fassen. Denn Muße ist 'mehr' und anderes als Freizeit-aber was ist das für ein Mehr? Was für ein Glück verspricht die Muße? Gibt es eine Freiheit, die sich nur in Muße realisiert? Der Band nähert sich dem Thema der Muße aus den disziplinären Perspektiven von Philosophie, Theologie, Soziologie, Psychologie und Medizin. Diese Perspektiven erschließen ein Feld von Konzepten, von denen her sich Muße verstehen lässt: Arbeit und Freizeit, Kontemplation, Gelassenheit und Achtsamkeit.

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