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In this work, the impact of laser cutting and a subsequent pre-deformation on the fatigue behavior of AISI 304 was investigated. This represents a typical process chain in steel sheet manufacturing. Laser cutting trials with variating process parameters were evaluated with regard to resulting dross formation and surface roughness. A subsequent deformation can influence the appearance of the laser cut edge. Fatigue tests up to 108 load cycles were carried out on specimens which were processed with selected parameter sets. It can be shown that dross attachment is the failure relevant feature which sets up a shape dependent, crack inducing notch effect. Furthermore, pre-deformation can detach melt droplets and therefore increase the fatigue strength.

The reaction of magnesium hydride with water is a very promising means to generate hydrogen for fuel cell applications as MgH 2 is cheap, non-toxic, has a very long shelf life as well as an extremely high hydrogen storage capacity of up to 15.3 wt.% in hydrolysis reactions. However, pure MgH 2 reacts only very slowly and incompletely with water and previous attempts to increase the hydrogen release kinetics and yields often involved the addition of large amounts of Bronsted acids, high-energy ball milling or expensive noble metal catalysts. Here, we present a systematic study on how MgH 2 is easily activated by the addition of small amounts of certain metal halides to make it react with water in a highly dynamic fashion. Possible mechanisms of this activation are discussed, which were illuminated by in situ measurements of pH and hydrogen normal volume flux during hydrolysis reactions under pseudo-isothermal conditions as well as ex situ X-ray powder diffraction. Furthermore, application-related issues like the influence of water hardness and quality on the hydrolysis reaction are addressed.

The environmental aspects of ore processing and waste treatment call for an optimization of applied technologies. There, understanding of the structure and complexation mechanism on a molecular scale is indispensable. Here, the complexation of U

A simple synthesis based on UO

Deutschland ist im weltweiten Vergleich ein relativ rohstoffarmes Land, wenn man Rohstoffe im Sinne von Bodenschatzen versteht. Fur die vorwiegend auf Industrieprodukte und Dienstleistungen ausgerichtete deutsche Wirtschaft ist jedoch eine andere Ressource entscheidend: das Arbeitskapital. Die Menschen sorgen mit ihrer Arbeit, ihren Ideen und ihrer Kreativitat dafur, dass Deutschland zu den fuhrenden Wirtschaftsnationen der Welt gehort.