Browsing Fakultät für Physik (inkl. GAUSS) by Advisor & Referee "Pundt, Astrid Prof. Dr."
Now showing items 1-19 of 19
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Interlayer effect on the hydrogen uptake in Vanadium films: Stress development, surface topography and optical behavior changes
(2023-07-13)The purpose of this study is to investigate hydrogen absorption-related properties changes of nanocrystalline thin films by varying the elastic constraints condition. The elastic constraint condition is varied by using ... -
Verformungsverhalten nanoskaliger Dünnschichten bei AFM-Indentierung
(2023-02-20)Nanoscaled materials differ in their mechanical properties from their bulk counterparts. Reasons therefore are e. g. the different ratio of surface and volume, which leads to different deformation mechanisms. In the case ... -
Mikrostrukturänderungen durch hohe elektrische Stromdichten in Eisen-Kohlenstoff Dünnschichten
(2021-08-11)Processing of materials with high electric and magnetic fields is a growing topic in material science. Yet, the interactions of fields and currents are complex and not fully understood. Therefore, the impact of high direct ... -
Hydrogen diffusion and hydride formation in grain boundary rich magnesium
(2019-05-06)In the last decade Magnesium (Mg) has attracted much interest as a storage material for hydrogen in a future hydrogen energy based economy. The reasons are its high reversible hydrogen capacity of up to 7,6 wt% and its ... -
In situ studies on palladium/rutile titanium dioxide exposed to low pressure hydrogen gas environments
(2018-11-12)The interaction of hydrogen gas with the palladium/rutile titanium dioxide model system was investigated with strong focus on the interface and its vicinity. Palladium (Pd) films were deposited on pretreated rutile titanium ... -
Ionenstrahlinduzierte selbst-organisierte Musterbildung auf einfachen Oberflächen Theorie und Experiment
(2018-05-30)In the thesis at hand, ripple pattern formation on amorphous carbon and Si surfaces has been investigated at room temperature during low energy Ne and Ar ion irradiation as a function of the ion incidence angle. Monte ... -
Nanoscale Waveguiding Studied by Lensless Coherent Diffractive Imaging using EUV High-Harmonic Generation Source
(2017-07-24)The challenge of nanometric imaging drives intense efforts in applied sciences and fundamental research. Following the physical law of diffraction, the utilization of extreme ultraviolet (EUV) or X-ray radiation for imaging ... -
Hydrogen absorption property of nanocrystalline-magnesium films
(2016-11-07)The purpose of this study is to investigate hydrogen absorption properties of grain boundary rich pure magnesium film. X-ray diffraction (XRD) measurements has been carried out to estimate microstructures, texture, lattice ... -
Critical thicknesses in Nb-H thin films: coherent and incoherent phase transitions, change of precipitation and growth modes and ultrahigh mechanical stress
(2016-08-03)For nanoscale systems such as Me-H thin films, changes of physical properties have been suggested to appear below certain critical sizes. The probable existence of these critical sizes and the related changes of thermodynamical ... -
Einfluss von gelöstem Wasserstoff auf die Versetzungsbildung bei plastischer Verformung von Metallen
(2016-03-11)Dissolved hydrogen in metals leads in many cases to a reduction in the quality of mechanical properties. There are many effects that can be attributed to the solution of hydrogen. These are collectively referred to as ... -
Extended TOF-SIMS analysis on low-nickel austenitic stainless steels: The influence of oxide layers on hydrogen embrittlement
(2016-01-18)Hydrogen embrittlement (HE) of low-nickel austenitic stainless steels were studied with special attention to the impact of the microstructural properties such as strain induced α’-martensite, grain size, dislocation density ... -
Dünne Palladium-Wasserstoff-Schichten als Modellsystem: Thermodynamik struktureller Phasenübergänge unter elastischen und mikrostrukturellen Zwangsbedingungen
(2015-07-07)Using the formation of a hydride phase in palladium-hydrogen thin films with 5 nm to 2000 nm thickness as a model, this work investigates the impact of film thickness as well as microstructural and elastic constraints on ... -
Localized Proton Magnetic Resonance Spectroscopy of Mouse Brain In Vivo at High Magnetic Field Strength
(2014-10-01)This work describes the implementation and optimization of single-voxel proton magnetic resonance spectroscopy for absolute quantification of regional metabolite concentration in mouse brain in vivo at 9.4 T. Optimized scheme ... -
Hydrogen in V-Fe thin films and Fe/V-Fe multi-layered thin films
(2011-11-25)In this thesis, hydrogen induced biaxial stress and local distribution of hydrogen in V-Fe films and V-Fe/Fe multi-layered films were investigated. The stress development and stress relaxation ... -
Controlled delamination of metal films by hydrogen loading
(2009-01-28)In this work we quantitatively determine the adhesion energy between metal films and their substrates. Therefore a new controlled buckling technique is established, applying the strong ... -
Computer Simulations for Hydrogen Loaded Palladium Clusters
(2007-08-07)In this work, a new expression for the chemical potential μ of H in Pd is used, which relies on an extension of Widom's particle insertion method. Being an exact expression, this μ contains ... -
Wasserstoffabsorption in epitaktischen Niobschichten: eine STM-Studie
(2007-02-19)In this work the phase transition of the system Niobium Hydrogen in thin films was investigated. The epitaxial Niobium films were fabricated using ion sputtering on sapphire substrates. The ... -
Wachstum und Grenzflächenbeschaffenheit oxidischer Ausscheidungen in Silber
(2003-12-02)The chemical composition of metal/oxide (M/O)- interfaces was studied for an internally oxidized Ag1at.%Mg- and Ag1at.%Mn- alloy with MgO- and Mn3O4- nanoprecipitates in a dilute Ag matrix, ... -
Spannungen, Dehnungen und Lage der Phasengrenzen in dünnen Nb- und Y-Schichten bei Wasserstoffbe- und -entladung
(2002-07-17)In this work the influence of the stresses induced by hydrogen loading on the position of phase boundaries in niobium and yttrium thin films is studied. The films were loaded with hydrogen ...