Semester Projects

Contact:
Prof. Dr. Michel Kenzelmann
Laboratory for Neutron Scattering and Imaging (LNS)
+41 56 310 5381
michel.kenzelmann@psi.ch

Clays are application relevant layered porous materials. In this context understanding of water diffusion and molecular ordering of water is of interest. In clay particles water is usually intercalated in a form of integer number of molecular water layers. Recently, a theoretically predicted "1.5" layer state has been observed. In this project the local water diffusion in Li-fluorhectorite (at 1, 1.5 and 2 water layer hydration state) will be measured by means of quasielastic neutron scattering at the FOCUS spectrometer at PSI. Furthermore a novel test experiment on the same instrument will be carried out to measure the structure of the water.

Supervisor: Fanni Juranyi

Water scarcity is the main limit to food production worldwide. Recent studies suggest that mucilage exudation by roots helps plants to better tolerate drought. Wet mucilage is a complex hydrogel, which can take up up to 99.9 % of water. Here the diffusion of water will be measured on a molecular scale by quasielastic neutron scattering at the spectrometer FOCUS at PSI. The focus is on the hydration dependence and to find out whether its main component (polygalacturonicacid) plays a determining role in the dynamics or not. This project is a collaboration with the Georg-August-University Göttingen, Germany.

Supervisor: Fanni Juranyi

The aim of the proposed project is to measure the flux and the energy resolution of the MICA-monochromator, which can be used for neutron wavelengths between 6 and 16 Å. Furthermore the contamination by higher-order reflections and the background shall be checked. The project includes experimental beam-time on FOCUS (4-5 days) and data analysis using state–of–the-art software available in our lab. To demonstrate the performance of the monochromator a standard sample will be investigated.

Supervisor: Jan Peter Embs

High-precision measurements of reference samples on the reflectometers Amor, Morpheus and Narziss are needed to establish a new standard for calibrating these instruments, which are used to investigate thin film samples, heterostructures and bio-membranes. The project involves alignment and neutron reflectivity measurements of several (existing) samples, followed by an analysis using standard simulation tools such as Parratt or MOTOFIT. For the measurements 1 to 2 days on each instrument are necessary. The analysis is performed with state-of-the-art software packages.

Supervisors: Jochen Stahn and Thomas Geue.