Stefanie Hopfe

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Since the end of the eighties Pulsed Laser Deposition (PLD) has been successfully used for the preparation of multilayers having X-ray optical quality. Outstanding features of the PLD-process are high thickness uniformity, precision of deposition process, formation of smooth interfaces and suppression of columnar thin film growth regime. In order to gain(More)
In most modern technologies such as flat screens, highly effective magnets and lasers, as well as luminescence phosphors, Rare Earth Elements (REE) are used. Unfortunately no environmentally friendly recycling process exists so far. In comparison to other elements the interaction of microorganisms with REE has been studied to a less extent. However, as REE(More)
Microorganisms have developed various mechanisms to deal with metals, thus providing numerous tools that can be used in biohydrometallurgical processes. “Biomining” processes—including bioleaching and biooxidation processes—facilitate the degradation of minerals, accompanied by a release of metals. These processes are especially attractive for low-grade(More)
Microstructural properties of Ni/C multilayers prepared by PLD (pulsed laser deposition) have been investigated after heat treatment in vacuum at temperatures in the range of 50 degrees C to 500 degrees C. X-ray diffractometry, X-ray reflectometry, fluorescence EXAFS (extended X-ray absorption fine structure) and HREM (high resolution transmission electron(More)
The interface structure of Mo/Si-multilayers prepared by Pulsed Laser Deposition (PLD) on Si substrates at room temperature has been investigated. Already the in-situ ellipsometer data acquired during film growth indicate a particular behaviour of this material system that is caused by reaction/diffusion processes of the condensing atoms. MoSi(x)(More)
Multilayer thin films consisting of alternatingpure molybdenum and silicon layers with layer thicknesses of a few nanometers are of increasing interest for soft X-ray optical applications in the wavelength region above the Si-L edge (i = 12.4 nm). In order to enhance the thermal and long term stability, which is of great importance for applications with(More)
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